# HG changeset patch
# User herrick
# Date 1572276103 14400
# Node ID a9316bb4c0e8870d63b5c16aaf7f535f69139b1b
# Parent  72daf2e005cddb070b7323017c9cb46a8e3c9de3# Parent  7f27d70a2424e6208d8705ac456d45275752c6fe
Merge

diff -r 72daf2e005cd -r a9316bb4c0e8 .hgtags
--- a/.hgtags	Thu Oct 24 17:14:42 2019 -0400
+++ b/.hgtags	Mon Oct 28 11:21:43 2019 -0400
@@ -592,3 +592,4 @@
 5c83830390baafb76a1fbe33443c57620bd45fb9 jdk-14+17
 e84d8379815ba0d3e50fb096d28c25894cb50b8c jdk-14+18
 9b67dd88a9313e982ec5f710a7747161bc8f0c23 jdk-14+19
+54ffb15c48399dd59922ee22bb592d815307e77c jdk-14+20
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/cpu/aarch64/gc/z/zGlobals_aarch64.cpp
--- a/src/hotspot/cpu/aarch64/gc/z/zGlobals_aarch64.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/cpu/aarch64/gc/z/zGlobals_aarch64.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -142,8 +142,7 @@
 size_t ZPlatformAddressOffsetBits() {
   const size_t min_address_offset_bits = 42; // 4TB
   const size_t max_address_offset_bits = 44; // 16TB
-  const size_t virtual_to_physical_ratio = 7; // 7:1
-  const size_t address_offset = ZUtils::round_up_power_of_2(MaxHeapSize * virtual_to_physical_ratio);
+  const size_t address_offset = ZUtils::round_up_power_of_2(MaxHeapSize * ZVirtualToPhysicalRatio);
   const size_t address_offset_bits = log2_intptr(address_offset);
   return MIN2(MAX2(address_offset_bits, min_address_offset_bits), max_address_offset_bits);
 }
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/cpu/aarch64/gc/z/zGlobals_aarch64.hpp
--- a/src/hotspot/cpu/aarch64/gc/z/zGlobals_aarch64.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/cpu/aarch64/gc/z/zGlobals_aarch64.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -24,23 +24,13 @@
 #ifndef CPU_AARCH64_GC_Z_ZGLOBALS_AARCH64_HPP
 #define CPU_AARCH64_GC_Z_ZGLOBALS_AARCH64_HPP
 
-//
-// Page Allocation Tiers
-// ---------------------
-//
-//  Page Type     Page Size     Object Size Limit     Object Alignment
-//  ------------------------------------------------------------------
-//  Small         2M            <= 265K               <MinObjAlignmentInBytes>
-//  Medium        32M           <= 4M                 4K
-//  Large         X*M           > 4M                  2M
-//  ------------------------------------------------------------------
-//
 const size_t ZPlatformGranuleSizeShift      = 21; // 2MB
+const size_t ZPlatformHeapViews             = 3;
 const size_t ZPlatformNMethodDisarmedOffset = 4;
 const size_t ZPlatformCacheLineSize         = 64;
 
-uintptr_t    ZPlatformAddressBase();
-size_t       ZPlatformAddressOffsetBits();
-size_t       ZPlatformAddressMetadataShift();
+uintptr_t ZPlatformAddressBase();
+size_t ZPlatformAddressOffsetBits();
+size_t ZPlatformAddressMetadataShift();
 
 #endif // CPU_AARCH64_GC_Z_ZGLOBALS_AARCH64_HPP
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/cpu/arm/c1_LIRGenerator_arm.cpp
--- a/src/hotspot/cpu/arm/c1_LIRGenerator_arm.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/cpu/arm/c1_LIRGenerator_arm.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -774,7 +774,7 @@
   bool is_oop = type == T_OBJECT || type == T_ARRAY;
   LIR_Opr result = new_register(type);
   value.load_item();
-  assert(type == T_INT || is_oop LP64_ONLY( || type == T_LONG ), "unexpected type");
+  assert(type == T_INT || is_oop || (type == T_LONG && VM_Version::supports_ldrexd()), "unexpected type");
   LIR_Opr tmp = (UseCompressedOops && is_oop) ? new_pointer_register() : LIR_OprFact::illegalOpr;
   __ xchg(addr, value.result(), result, tmp);
   return result;
@@ -783,7 +783,7 @@
 LIR_Opr LIRGenerator::atomic_add(BasicType type, LIR_Opr addr, LIRItem& value) {
   LIR_Opr result = new_register(type);
   value.load_item();
-  assert(type == T_INT LP64_ONLY( || type == T_LONG), "unexpected type");
+  assert(type == T_INT || (type == T_LONG && VM_Version::supports_ldrexd ()), "unexpected type");
   LIR_Opr tmp = new_register(type);
   __ xadd(addr, value.result(), result, tmp);
   return result;
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/cpu/ppc/templateInterpreterGenerator_ppc.cpp
--- a/src/hotspot/cpu/ppc/templateInterpreterGenerator_ppc.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/cpu/ppc/templateInterpreterGenerator_ppc.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -592,10 +592,10 @@
   __ load_const_optimized(R4_ARG2, (address) name, R11_scratch1);
   if (pass_oop) {
     __ mr(R5_ARG3, Rexception);
-    __ call_VM(Rexception, CAST_FROM_FN_PTR(address, InterpreterRuntime::create_klass_exception), false);
+    __ call_VM(Rexception, CAST_FROM_FN_PTR(address, InterpreterRuntime::create_klass_exception));
   } else {
     __ load_const_optimized(R5_ARG3, (address) message, R11_scratch1);
-    __ call_VM(Rexception, CAST_FROM_FN_PTR(address, InterpreterRuntime::create_exception), false);
+    __ call_VM(Rexception, CAST_FROM_FN_PTR(address, InterpreterRuntime::create_exception));
   }
 
   // Throw exception.
@@ -2105,7 +2105,7 @@
     // The member name argument must be restored if _invokestatic is re-executed after a PopFrame call.
     // Detect such a case in the InterpreterRuntime function and return the member name argument, or NULL.
     __ ld(R4_ARG2, 0, R18_locals);
-    __ MacroAssembler::call_VM(R4_ARG2, CAST_FROM_FN_PTR(address, InterpreterRuntime::member_name_arg_or_null), R4_ARG2, R19_method, R14_bcp, false);
+    __ call_VM(R4_ARG2, CAST_FROM_FN_PTR(address, InterpreterRuntime::member_name_arg_or_null), R4_ARG2, R19_method, R14_bcp);
     __ restore_interpreter_state(R11_scratch1, /*bcp_and_mdx_only*/ true);
     __ cmpdi(CCR0, R4_ARG2, 0);
     __ beq(CCR0, L_done);
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/cpu/s390/interp_masm_s390.cpp
--- a/src/hotspot/cpu/s390/interp_masm_s390.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/cpu/s390/interp_masm_s390.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -1072,8 +1072,7 @@
 void InterpreterMacroAssembler::unlock_object(Register monitor, Register object) {
 
   if (UseHeavyMonitors) {
-    call_VM(noreg, CAST_FROM_FN_PTR(address, InterpreterRuntime::monitorexit),
-            monitor, /*check_for_exceptions=*/ true);
+    call_VM(noreg, CAST_FROM_FN_PTR(address, InterpreterRuntime::monitorexit), monitor);
     return;
   }
 
@@ -1147,8 +1146,7 @@
   // The lock has been converted into a heavy lock and hence
   // we need to get into the slow case.
   z_stg(object, obj_entry);   // Restore object entry, has been cleared above.
-  call_VM(noreg, CAST_FROM_FN_PTR(address, InterpreterRuntime::monitorexit),
-          monitor,  /*check_for_exceptions=*/false);
+  call_VM(noreg, CAST_FROM_FN_PTR(address, InterpreterRuntime::monitorexit), monitor);
 
   // }
 
@@ -2095,7 +2093,7 @@
     Label jvmti_post_done;
     MacroAssembler::load_and_test_int(Z_R0, Address(Z_thread, JavaThread::interp_only_mode_offset()));
     z_bre(jvmti_post_done);
-    call_VM(noreg, CAST_FROM_FN_PTR(address, InterpreterRuntime::post_method_entry), /*check_exceptions=*/false);
+    call_VM(noreg, CAST_FROM_FN_PTR(address, InterpreterRuntime::post_method_entry));
     bind(jvmti_post_done);
   }
 }
@@ -2129,7 +2127,7 @@
     MacroAssembler::load_and_test_int(Z_R0, Address(Z_thread, JavaThread::interp_only_mode_offset()));
     z_bre(jvmti_post_done);
     if (!native_method) push(state); // see frame::interpreter_frame_result()
-    call_VM(noreg, CAST_FROM_FN_PTR(address, InterpreterRuntime::post_method_exit), /*check_exceptions=*/false);
+    call_VM(noreg, CAST_FROM_FN_PTR(address, InterpreterRuntime::post_method_exit));
     if (!native_method) pop(state);
     bind(jvmti_post_done);
   }
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/cpu/x86/gc/shenandoah/shenandoahBarrierSetAssembler_x86.cpp
--- a/src/hotspot/cpu/x86/gc/shenandoah/shenandoahBarrierSetAssembler_x86.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/cpu/x86/gc/shenandoah/shenandoahBarrierSetAssembler_x86.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -247,54 +247,6 @@
   __ bind(done);
 }
 
-void ShenandoahBarrierSetAssembler::resolve_forward_pointer(MacroAssembler* masm, Register dst, Register tmp) {
-  assert(ShenandoahCASBarrier, "should be enabled");
-  Label is_null;
-  __ testptr(dst, dst);
-  __ jcc(Assembler::zero, is_null);
-  resolve_forward_pointer_not_null(masm, dst, tmp);
-  __ bind(is_null);
-}
-
-void ShenandoahBarrierSetAssembler::resolve_forward_pointer_not_null(MacroAssembler* masm, Register dst, Register tmp) {
-  assert(ShenandoahCASBarrier || ShenandoahLoadRefBarrier, "should be enabled");
-  // The below loads the mark word, checks if the lowest two bits are
-  // set, and if so, clear the lowest two bits and copy the result
-  // to dst. Otherwise it leaves dst alone.
-  // Implementing this is surprisingly awkward. I do it here by:
-  // - Inverting the mark word
-  // - Test lowest two bits == 0
-  // - If so, set the lowest two bits
-  // - Invert the result back, and copy to dst
-
-  bool borrow_reg = (tmp == noreg);
-  if (borrow_reg) {
-    // No free registers available. Make one useful.
-    tmp = LP64_ONLY(rscratch1) NOT_LP64(rdx);
-    if (tmp == dst) {
-      tmp = LP64_ONLY(rscratch2) NOT_LP64(rcx);
-    }
-    __ push(tmp);
-  }
-
-  assert_different_registers(dst, tmp);
-
-  Label done;
-  __ movptr(tmp, Address(dst, oopDesc::mark_offset_in_bytes()));
-  __ notptr(tmp);
-  __ testb(tmp, markWord::marked_value);
-  __ jccb(Assembler::notZero, done);
-  __ orptr(tmp, markWord::marked_value);
-  __ notptr(tmp);
-  __ mov(dst, tmp);
-  __ bind(done);
-
-  if (borrow_reg) {
-    __ pop(tmp);
-  }
-}
-
-
 void ShenandoahBarrierSetAssembler::load_reference_barrier_not_null(MacroAssembler* masm, Register dst) {
   assert(ShenandoahLoadRefBarrier, "Should be enabled");
 
@@ -605,8 +557,9 @@
                                                 bool exchange, Register tmp1, Register tmp2) {
   assert(ShenandoahCASBarrier, "Should only be used when CAS barrier is enabled");
   assert(oldval == rax, "must be in rax for implicit use in cmpxchg");
+  assert_different_registers(oldval, newval, tmp1, tmp2);
 
-  Label retry, done;
+  Label L_success, L_failure;
 
   // Remember oldval for retry logic below
 #ifdef _LP64
@@ -618,8 +571,10 @@
     __ movptr(tmp1, oldval);
   }
 
-  // Step 1. Try to CAS with given arguments. If successful, then we are done,
-  // and can safely return.
+  // Step 1. Fast-path.
+  //
+  // Try to CAS with given arguments. If successful, then we are done.
+
   if (os::is_MP()) __ lock();
 #ifdef _LP64
   if (UseCompressedOops) {
@@ -629,21 +584,32 @@
   {
     __ cmpxchgptr(newval, addr);
   }
-  __ jcc(Assembler::equal, done, true);
+  __ jcc(Assembler::equal, L_success);
 
   // Step 2. CAS had failed. This may be a false negative.
   //
   // The trouble comes when we compare the to-space pointer with the from-space
-  // pointer to the same object. To resolve this, it will suffice to resolve both
-  // oldval and the value from memory -- this will give both to-space pointers.
+  // pointer to the same object. To resolve this, it will suffice to resolve
+  // the value from memory -- this will give both to-space pointers.
   // If they mismatch, then it was a legitimate failure.
   //
+  // Before reaching to resolve sequence, see if we can avoid the whole shebang
+  // with filters.
+
+  // Filter: when offending in-memory value is NULL, the failure is definitely legitimate
+  __ testptr(oldval, oldval);
+  __ jcc(Assembler::zero, L_failure);
+
+  // Filter: when heap is stable, the failure is definitely legitimate
 #ifdef _LP64
-  if (UseCompressedOops) {
-    __ decode_heap_oop(tmp1);
-  }
+  const Register thread = r15_thread;
+#else
+  const Register thread = tmp2;
+  __ get_thread(thread);
 #endif
-  resolve_forward_pointer(masm, tmp1);
+  Address gc_state(thread, in_bytes(ShenandoahThreadLocalData::gc_state_offset()));
+  __ testb(gc_state, ShenandoahHeap::HAS_FORWARDED);
+  __ jcc(Assembler::zero, L_failure);
 
 #ifdef _LP64
   if (UseCompressedOops) {
@@ -654,18 +620,70 @@
   {
     __ movptr(tmp2, oldval);
   }
-  resolve_forward_pointer(masm, tmp2);
+
+  // Decode offending in-memory value.
+  // Test if-forwarded
+  __ testb(Address(tmp2, oopDesc::mark_offset_in_bytes()), markWord::marked_value);
+  __ jcc(Assembler::noParity, L_failure);  // When odd number of bits, then not forwarded
+  __ jcc(Assembler::zero, L_failure);      // When it is 00, then also not forwarded
+
+  // Load and mask forwarding pointer
+  __ movptr(tmp2, Address(tmp2, oopDesc::mark_offset_in_bytes()));
+  __ shrptr(tmp2, 2);
+  __ shlptr(tmp2, 2);
 
+#ifdef _LP64
+  if (UseCompressedOops) {
+    __ decode_heap_oop(tmp1); // decode for comparison
+  }
+#endif
+
+  // Now we have the forwarded offender in tmp2.
+  // Compare and if they don't match, we have legitimate failure
   __ cmpptr(tmp1, tmp2);
-  __ jcc(Assembler::notEqual, done, true);
+  __ jcc(Assembler::notEqual, L_failure);
+
+  // Step 3. Need to fix the memory ptr before continuing.
+  //
+  // At this point, we have from-space oldval in the register, and its to-space
+  // address is in tmp2. Let's try to update it into memory. We don't care if it
+  // succeeds or not. If it does, then the retrying CAS would see it and succeed.
+  // If this fixup fails, this means somebody else beat us to it, and necessarily
+  // with to-space ptr store. We still have to do the retry, because the GC might
+  // have updated the reference for us.
 
-  // Step 3. Try to CAS again with resolved to-space pointers.
+#ifdef _LP64
+  if (UseCompressedOops) {
+    __ encode_heap_oop(tmp2); // previously decoded at step 2.
+  }
+#endif
+
+  if (os::is_MP()) __ lock();
+#ifdef _LP64
+  if (UseCompressedOops) {
+    __ cmpxchgl(tmp2, addr);
+  } else
+#endif
+  {
+    __ cmpxchgptr(tmp2, addr);
+  }
+
+  // Step 4. Try to CAS again.
   //
-  // Corner case: it may happen that somebody stored the from-space pointer
-  // to memory while we were preparing for retry. Therefore, we can fail again
-  // on retry, and so need to do this in loop, always resolving the failure
-  // witness.
-  __ bind(retry);
+  // This is guaranteed not to have false negatives, because oldval is definitely
+  // to-space, and memory pointer is to-space as well. Nothing is able to store
+  // from-space ptr into memory anymore. Make sure oldval is restored, after being
+  // garbled during retries.
+  //
+#ifdef _LP64
+  if (UseCompressedOops) {
+    __ movl(oldval, tmp2);
+  } else
+#endif
+  {
+    __ movptr(oldval, tmp2);
+  }
+
   if (os::is_MP()) __ lock();
 #ifdef _LP64
   if (UseCompressedOops) {
@@ -675,41 +693,28 @@
   {
     __ cmpxchgptr(newval, addr);
   }
-  __ jcc(Assembler::equal, done, true);
+  if (!exchange) {
+    __ jccb(Assembler::equal, L_success); // fastpath, peeking into Step 5, no need to jump
+  }
 
-#ifdef _LP64
-  if (UseCompressedOops) {
-    __ movl(tmp2, oldval);
-    __ decode_heap_oop(tmp2);
-  } else
-#endif
-  {
-    __ movptr(tmp2, oldval);
-  }
-  resolve_forward_pointer(masm, tmp2);
-
-  __ cmpptr(tmp1, tmp2);
-  __ jcc(Assembler::equal, retry, true);
+  // Step 5. If we need a boolean result out of CAS, set the flag appropriately.
+  // and promote the result. Note that we handle the flag from both the 1st and 2nd CAS.
+  // Otherwise, failure witness for CAE is in oldval on all paths, and we can return.
 
-  // Step 4. If we need a boolean result out of CAS, check the flag again,
-  // and promote the result. Note that we handle the flag from both the CAS
-  // itself and from the retry loop.
-  __ bind(done);
-  if (!exchange) {
+  if (exchange) {
+    __ bind(L_failure);
+    __ bind(L_success);
+  } else {
     assert(res != NULL, "need result register");
-#ifdef _LP64
-    __ setb(Assembler::equal, res);
-    __ movzbl(res, res);
-#else
-    // Need something else to clean the result, because some registers
-    // do not have byte encoding that movzbl wants. Cannot do the xor first,
-    // because it modifies the flags.
-    Label res_non_zero;
+
+    Label exit;
+    __ bind(L_failure);
+    __ xorptr(res, res);
+    __ jmpb(exit);
+
+    __ bind(L_success);
     __ movptr(res, 1);
-    __ jcc(Assembler::equal, res_non_zero, true);
-    __ xorptr(res, res);
-    __ bind(res_non_zero);
-#endif
+    __ bind(exit);
   }
 }
 
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/cpu/x86/gc/shenandoah/shenandoahBarrierSetAssembler_x86.hpp
--- a/src/hotspot/cpu/x86/gc/shenandoah/shenandoahBarrierSetAssembler_x86.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/cpu/x86/gc/shenandoah/shenandoahBarrierSetAssembler_x86.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -55,9 +55,6 @@
                                     bool tosca_live,
                                     bool expand_call);
 
-  void resolve_forward_pointer(MacroAssembler* masm, Register dst, Register tmp = noreg);
-  void resolve_forward_pointer_not_null(MacroAssembler* masm, Register dst, Register tmp = noreg);
-
   void load_reference_barrier_not_null(MacroAssembler* masm, Register dst);
 
   void storeval_barrier_impl(MacroAssembler* masm, Register dst, Register tmp);
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/cpu/x86/gc/z/zGlobals_x86.cpp
--- a/src/hotspot/cpu/x86/gc/z/zGlobals_x86.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/cpu/x86/gc/z/zGlobals_x86.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -142,8 +142,7 @@
 size_t ZPlatformAddressOffsetBits() {
   const size_t min_address_offset_bits = 42; // 4TB
   const size_t max_address_offset_bits = 44; // 16TB
-  const size_t virtual_to_physical_ratio = 7; // 7:1
-  const size_t address_offset = ZUtils::round_up_power_of_2(MaxHeapSize * virtual_to_physical_ratio);
+  const size_t address_offset = ZUtils::round_up_power_of_2(MaxHeapSize * ZVirtualToPhysicalRatio);
   const size_t address_offset_bits = log2_intptr(address_offset);
   return MIN2(MAX2(address_offset_bits, min_address_offset_bits), max_address_offset_bits);
 }
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/cpu/x86/gc/z/zGlobals_x86.hpp
--- a/src/hotspot/cpu/x86/gc/z/zGlobals_x86.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/cpu/x86/gc/z/zGlobals_x86.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -24,23 +24,13 @@
 #ifndef CPU_X86_GC_Z_ZGLOBALS_X86_HPP
 #define CPU_X86_GC_Z_ZGLOBALS_X86_HPP
 
-//
-// Page Allocation Tiers
-// ---------------------
-//
-//  Page Type     Page Size     Object Size Limit     Object Alignment
-//  ------------------------------------------------------------------
-//  Small         2M            <= 265K               <MinObjAlignmentInBytes>
-//  Medium        32M           <= 4M                 4K
-//  Large         X*M           > 4M                  2M
-//  ------------------------------------------------------------------
-//
 const size_t ZPlatformGranuleSizeShift      = 21; // 2MB
+const size_t ZPlatformHeapViews             = 3;
 const size_t ZPlatformNMethodDisarmedOffset = 4;
 const size_t ZPlatformCacheLineSize         = 64;
 
-uintptr_t    ZPlatformAddressBase();
-size_t       ZPlatformAddressOffsetBits();
-size_t       ZPlatformAddressMetadataShift();
+uintptr_t ZPlatformAddressBase();
+size_t ZPlatformAddressOffsetBits();
+size_t ZPlatformAddressMetadataShift();
 
 #endif // CPU_X86_GC_Z_ZGLOBALS_X86_HPP
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/os/posix/gc/z/zInitialize_posix.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/os/posix/gc/z/zInitialize_posix.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -0,0 +1,29 @@
+/*
+ * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+#include "precompiled.hpp"
+#include "gc/z/zInitialize.hpp"
+
+void ZInitialize::initialize_os() {
+  // Does nothing
+}
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/os/posix/gc/z/zVirtualMemory_posix.cpp
--- a/src/hotspot/os/posix/gc/z/zVirtualMemory_posix.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/os/posix/gc/z/zVirtualMemory_posix.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -29,6 +29,10 @@
 #include <sys/mman.h>
 #include <sys/types.h>
 
+void ZVirtualMemoryManager::initialize_os() {
+  // Does nothing
+}
+
 static void unmap(uintptr_t start, size_t size) {
   const int res = munmap((void*)start, size);
   assert(res == 0, "Failed to unmap memory");
@@ -51,7 +55,7 @@
   return true;
 }
 
-bool ZVirtualMemoryManager::reserve_platform(uintptr_t start, size_t size) {
+bool ZVirtualMemoryManager::reserve_contiguous_platform(uintptr_t start, size_t size) {
   // Reserve address views
   const uintptr_t marked0 = ZAddress::marked0(start);
   const uintptr_t marked1 = ZAddress::marked1(start);
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/os/windows/os_windows.cpp
--- a/src/hotspot/os/windows/os_windows.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/os/windows/os_windows.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -795,6 +795,10 @@
   }
 }
 
+uint os::processor_id() {
+  return (uint)GetCurrentProcessorNumber();
+}
+
 void os::set_native_thread_name(const char *name) {
 
   // See: http://msdn.microsoft.com/en-us/library/xcb2z8hs.aspx
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/os_cpu/linux_ppc/thread_linux_ppc.cpp
--- a/src/hotspot/os_cpu/linux_ppc/thread_linux_ppc.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/os_cpu/linux_ppc/thread_linux_ppc.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -65,21 +65,22 @@
     }
 
     if (ret_frame.is_interpreted_frame()) {
-       frame::ijava_state* istate = ret_frame.get_ijava_state();
-       if (MetaspaceObj::is_valid((Method*)(istate->method)) == false) {
-         return false;
-       }
-       uint64_t reg_bcp = uc->uc_mcontext.regs->gpr[14/*R14_bcp*/];
-       uint64_t istate_bcp = istate->bcp;
-       uint64_t code_start = (uint64_t)(((Method*)(istate->method))->code_base());
-       uint64_t code_end = (uint64_t)(((Method*)istate->method)->code_base() + ((Method*)istate->method)->code_size());
-       if (istate_bcp >= code_start && istate_bcp < code_end) {
-         // we have a valid bcp, don't touch it, do nothing
-       } else if (reg_bcp >= code_start && reg_bcp < code_end) {
-         istate->bcp = reg_bcp;
+      frame::ijava_state *istate = ret_frame.get_ijava_state();
+      const Method *m = (const Method*)(istate->method);
+      if (!Method::is_valid_method(m)) return false;
+      if (!Metaspace::contains(m->constMethod())) return false;
+
+      uint64_t reg_bcp = uc->uc_mcontext.regs->gpr[14/*R14_bcp*/];
+      uint64_t istate_bcp = istate->bcp;
+      uint64_t code_start = (uint64_t)(m->code_base());
+      uint64_t code_end = (uint64_t)(m->code_base() + m->code_size());
+      if (istate_bcp >= code_start && istate_bcp < code_end) {
+        // we have a valid bcp, don't touch it, do nothing
+      } else if (reg_bcp >= code_start && reg_bcp < code_end) {
+        istate->bcp = reg_bcp;
       } else {
-         return false;
-       }
+        return false;
+      }
     }
     if (!ret_frame.safe_for_sender(this)) {
       // nothing else to try if the frame isn't good
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/os_cpu/linux_s390/thread_linux_s390.cpp
--- a/src/hotspot/os_cpu/linux_s390/thread_linux_s390.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/os_cpu/linux_s390/thread_linux_s390.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -63,21 +63,24 @@
 
     if (ret_frame.is_interpreted_frame()) {
       frame::z_ijava_state* istate = ret_frame.ijava_state_unchecked();
-       if ((stack_base() >= (address)istate && (address)istate > stack_end()) ||
-           MetaspaceObj::is_valid((Method*)(istate->method)) == false) {
-         return false;
-       }
-       uint64_t reg_bcp = uc->uc_mcontext.gregs[13/*Z_BCP*/];
-       uint64_t istate_bcp = istate->bcp;
-       uint64_t code_start = (uint64_t)(((Method*)(istate->method))->code_base());
-       uint64_t code_end = (uint64_t)(((Method*)istate->method)->code_base() + ((Method*)istate->method)->code_size());
-       if (istate_bcp >= code_start && istate_bcp < code_end) {
-         // we have a valid bcp, don't touch it, do nothing
-       } else if (reg_bcp >= code_start && reg_bcp < code_end) {
-         istate->bcp = reg_bcp;
-       } else {
-         return false;
-       }
+      if (stack_base() >= (address)istate && (address)istate > stack_end()) {
+        return false;
+      }
+      const Method *m = (const Method*)(istate->method);
+      if (!Method::is_valid_method(m)) return false;
+      if (!Metaspace::contains(m->constMethod())) return false;
+
+      uint64_t reg_bcp = uc->uc_mcontext.gregs[13/*Z_BCP*/];
+      uint64_t istate_bcp = istate->bcp;
+      uint64_t code_start = (uint64_t)(m->code_base());
+      uint64_t code_end = (uint64_t)(m->code_base() + m->code_size());
+      if (istate_bcp >= code_start && istate_bcp < code_end) {
+        // we have a valid bcp, don't touch it, do nothing
+      } else if (reg_bcp >= code_start && reg_bcp < code_end) {
+        istate->bcp = reg_bcp;
+      } else {
+        return false;
+      }
     }
     if (!ret_frame.safe_for_sender(this)) {
       // nothing else to try if the frame isn't good
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/classfile/classFileParser.cpp
--- a/src/hotspot/share/classfile/classFileParser.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/classfile/classFileParser.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -2448,17 +2448,10 @@
       parsed_code_attribute = true;
 
       // Stack size, locals size, and code size
-      if (_major_version == 45 && _minor_version <= 2) {
-        cfs->guarantee_more(4, CHECK_NULL);
-        max_stack = cfs->get_u1_fast();
-        max_locals = cfs->get_u1_fast();
-        code_length = cfs->get_u2_fast();
-      } else {
-        cfs->guarantee_more(8, CHECK_NULL);
-        max_stack = cfs->get_u2_fast();
-        max_locals = cfs->get_u2_fast();
-        code_length = cfs->get_u4_fast();
-      }
+      cfs->guarantee_more(8, CHECK_NULL);
+      max_stack = cfs->get_u2_fast();
+      max_locals = cfs->get_u2_fast();
+      code_length = cfs->get_u4_fast();
       if (_need_verify) {
         guarantee_property(args_size <= max_locals,
                            "Arguments can't fit into locals in class file %s",
@@ -2489,13 +2482,8 @@
 
       unsigned int calculated_attribute_length = 0;
 
-      if (_major_version > 45 || (_major_version == 45 && _minor_version > 2)) {
-        calculated_attribute_length =
-            sizeof(max_stack) + sizeof(max_locals) + sizeof(code_length);
-      } else {
-        // max_stack, locals and length are smaller in pre-version 45.2 classes
-        calculated_attribute_length = sizeof(u1) + sizeof(u1) + sizeof(u2);
-      }
+      calculated_attribute_length =
+          sizeof(max_stack) + sizeof(max_locals) + sizeof(code_length);
       calculated_attribute_length +=
         code_length +
         sizeof(exception_table_length) +
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/classfile/javaClasses.cpp
--- a/src/hotspot/share/classfile/javaClasses.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/classfile/javaClasses.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -87,6 +87,21 @@
   ALL_INJECTED_FIELDS(DECLARE_INJECTED_FIELD)
 };
 
+// Register native methods of Object
+void java_lang_Object::register_natives(TRAPS) {
+  InstanceKlass* obj = SystemDictionary::Object_klass();
+  Method::register_native(obj, vmSymbols::hashCode_name(),
+                          vmSymbols::void_int_signature(), (address) &JVM_IHashCode, CHECK);
+  Method::register_native(obj, vmSymbols::wait_name(),
+                          vmSymbols::long_void_signature(), (address) &JVM_MonitorWait, CHECK);
+  Method::register_native(obj, vmSymbols::notify_name(),
+                          vmSymbols::void_method_signature(), (address) &JVM_MonitorNotify, CHECK);
+  Method::register_native(obj, vmSymbols::notifyAll_name(),
+                          vmSymbols::void_method_signature(), (address) &JVM_MonitorNotifyAll, CHECK);
+  Method::register_native(obj, vmSymbols::clone_name(),
+                          vmSymbols::void_object_signature(), (address) &JVM_Clone, THREAD);
+}
+
 int JavaClasses::compute_injected_offset(InjectedFieldID id) {
   return _injected_fields[id].compute_offset();
 }
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/classfile/javaClasses.hpp
--- a/src/hotspot/share/classfile/javaClasses.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/classfile/javaClasses.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -88,6 +88,13 @@
         BASIC_JAVA_CLASSES_DO_PART1(f) \
         BASIC_JAVA_CLASSES_DO_PART2(f)
 
+// Interface to java.lang.Object objects
+
+class java_lang_Object : AllStatic {
+ public:
+  static void register_natives(TRAPS);
+};
+
 // Interface to java.lang.String objects
 
 class java_lang_String : AllStatic {
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/classfile/systemDictionary.cpp
--- a/src/hotspot/share/classfile/systemDictionary.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/classfile/systemDictionary.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -1972,6 +1972,10 @@
     resolve_wk_klasses_through(WK_KLASS_ENUM_NAME(Class_klass), scan, CHECK);
   }
 
+  assert(WK_KLASS(Object_klass) != NULL, "well-known classes should now be initialized");
+
+  java_lang_Object::register_natives(CHECK);
+
   // Calculate offsets for String and Class classes since they are loaded and
   // can be used after this point.
   java_lang_String::compute_offsets();
@@ -2128,26 +2132,6 @@
   {
     MutexLocker mu1(SystemDictionary_lock, THREAD);
 
-    // See whether biased locking is enabled and if so set it for this
-    // klass.
-    // Note that this must be done past the last potential blocking
-    // point / safepoint. We might enable biased locking lazily using a
-    // VM_Operation to iterate the SystemDictionary and installing the
-    // biasable mark word into each InstanceKlass's prototype header.
-    // To avoid race conditions where we accidentally miss enabling the
-    // optimization for one class in the process of being added to the
-    // dictionary, we must not safepoint after the test of
-    // BiasedLocking::enabled().
-    if (UseBiasedLocking && BiasedLocking::enabled()) {
-      // Set biased locking bit for all loaded classes; it will be
-      // cleared if revocation occurs too often for this type
-      // NOTE that we must only do this when the class is initally
-      // defined, not each time it is referenced from a new class loader
-      if (k->class_loader() == class_loader()) {
-        k->set_prototype_header(markWord::biased_locking_prototype());
-      }
-    }
-
     // Make a new dictionary entry.
     Dictionary* dictionary = loader_data->dictionary();
     InstanceKlass* sd_check = find_class(d_hash, name, dictionary);
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/classfile/systemDictionary.hpp
--- a/src/hotspot/share/classfile/systemDictionary.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/classfile/systemDictionary.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -219,7 +219,6 @@
                                                                                                                 \
   /*end*/
 
-
 class SystemDictionary : AllStatic {
   friend class BootstrapInfo;
   friend class VMStructs;
@@ -383,7 +382,6 @@
     int limit = (int)end_id + 1;
     resolve_wk_klasses_until((WKID) limit, start_id, THREAD);
   }
-
 public:
   #define WK_KLASS_DECLARE(name, symbol) \
     static InstanceKlass* name() { return check_klass(_well_known_klasses[WK_KLASS_ENUM_NAME(name)]); } \
@@ -628,21 +626,6 @@
   // Basic find on classes in the midst of being loaded
   static Symbol* find_placeholder(Symbol* name, ClassLoaderData* loader_data);
 
-  // Add a placeholder for a class being loaded
-  static void add_placeholder(int index,
-                              Symbol* class_name,
-                              ClassLoaderData* loader_data);
-  static void remove_placeholder(int index,
-                                 Symbol* class_name,
-                                 ClassLoaderData* loader_data);
-
-  // Performs cleanups after resolve_super_or_fail. This typically needs
-  // to be called on failure.
-  // Won't throw, but can block.
-  static void resolution_cleanups(Symbol* class_name,
-                                  ClassLoaderData* loader_data,
-                                  TRAPS);
-
   // Resolve well-known classes so they can be used like SystemDictionary::String_klass()
   static void resolve_well_known_classes(TRAPS);
 
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/code/nmethod.cpp
--- a/src/hotspot/share/code/nmethod.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/code/nmethod.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -1826,57 +1826,183 @@
   }
 }
 
-#define NMETHOD_SENTINEL ((nmethod*)badAddress)
-
 nmethod* volatile nmethod::_oops_do_mark_nmethods;
 
-// An nmethod is "marked" if its _mark_link is set non-null.
-// Even if it is the end of the linked list, it will have a non-null link value,
-// as long as it is on the list.
-// This code must be MP safe, because it is used from parallel GC passes.
-bool nmethod::test_set_oops_do_mark() {
-  assert(nmethod::oops_do_marking_is_active(), "oops_do_marking_prologue must be called");
-  if (_oops_do_mark_link == NULL) {
-    // Claim this nmethod for this thread to mark.
-    if (Atomic::replace_if_null(NMETHOD_SENTINEL, &_oops_do_mark_link)) {
-      // Atomically append this nmethod (now claimed) to the head of the list:
-      nmethod* observed_mark_nmethods = _oops_do_mark_nmethods;
-      for (;;) {
-        nmethod* required_mark_nmethods = observed_mark_nmethods;
-        _oops_do_mark_link = required_mark_nmethods;
-        observed_mark_nmethods =
-          Atomic::cmpxchg(this, &_oops_do_mark_nmethods, required_mark_nmethods);
-        if (observed_mark_nmethods == required_mark_nmethods)
-          break;
-      }
-      // Mark was clear when we first saw this guy.
-      LogTarget(Trace, gc, nmethod) lt;
-      if (lt.is_enabled()) {
-        LogStream ls(lt);
-        CompileTask::print(&ls, this, "oops_do, mark", /*short_form:*/ true);
-      }
-      return false;
+void nmethod::oops_do_log_change(const char* state) {
+  LogTarget(Trace, gc, nmethod) lt;
+  if (lt.is_enabled()) {
+    LogStream ls(lt);
+    CompileTask::print(&ls, this, state, true /* short_form */);
+  }
+}
+
+bool nmethod::oops_do_try_claim() {
+  if (oops_do_try_claim_weak_request()) {
+    nmethod* result = oops_do_try_add_to_list_as_weak_done();
+    assert(result == NULL, "adding to global list as weak done must always succeed.");
+    return true;
+  }
+  return false;
+}
+
+bool nmethod::oops_do_try_claim_weak_request() {
+  assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
+
+  if ((_oops_do_mark_link == NULL) &&
+      (Atomic::replace_if_null(mark_link(this, claim_weak_request_tag), &_oops_do_mark_link))) {
+    oops_do_log_change("oops_do, mark weak request");
+    return true;
+  }
+  return false;
+}
+
+void nmethod::oops_do_set_strong_done(nmethod* old_head) {
+  _oops_do_mark_link = mark_link(old_head, claim_strong_done_tag);
+}
+
+nmethod::oops_do_mark_link* nmethod::oops_do_try_claim_strong_done() {
+  assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
+
+  oops_do_mark_link* old_next = Atomic::cmpxchg(mark_link(this, claim_strong_done_tag), &_oops_do_mark_link, mark_link(NULL, claim_weak_request_tag));
+  if (old_next == NULL) {
+    oops_do_log_change("oops_do, mark strong done");
+  }
+  return old_next;
+}
+
+nmethod::oops_do_mark_link* nmethod::oops_do_try_add_strong_request(nmethod::oops_do_mark_link* next) {
+  assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
+  assert(next == mark_link(this, claim_weak_request_tag), "Should be claimed as weak");
+
+  oops_do_mark_link* old_next = Atomic::cmpxchg(mark_link(this, claim_strong_request_tag), &_oops_do_mark_link, next);
+  if (old_next == next) {
+    oops_do_log_change("oops_do, mark strong request");
+  }
+  return old_next;
+}
+
+bool nmethod::oops_do_try_claim_weak_done_as_strong_done(nmethod::oops_do_mark_link* next) {
+  assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
+  assert(extract_state(next) == claim_weak_done_tag, "Should be claimed as weak done");
+
+  oops_do_mark_link* old_next = Atomic::cmpxchg(mark_link(extract_nmethod(next), claim_strong_done_tag), &_oops_do_mark_link, next);
+  if (old_next == next) {
+    oops_do_log_change("oops_do, mark weak done -> mark strong done");
+    return true;
+  }
+  return false;
+}
+
+nmethod* nmethod::oops_do_try_add_to_list_as_weak_done() {
+  assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
+
+  assert(extract_state(_oops_do_mark_link) == claim_weak_request_tag ||
+         extract_state(_oops_do_mark_link) == claim_strong_request_tag,
+         "must be but is nmethod " PTR_FORMAT " %u", p2i(extract_nmethod(_oops_do_mark_link)), extract_state(_oops_do_mark_link));
+
+  nmethod* old_head = Atomic::xchg(this, &_oops_do_mark_nmethods);
+  // Self-loop if needed.
+  if (old_head == NULL) {
+    old_head = this;
+  }
+  // Try to install end of list and weak done tag.
+  if (Atomic::cmpxchg(mark_link(old_head, claim_weak_done_tag), &_oops_do_mark_link, mark_link(this, claim_weak_request_tag)) == mark_link(this, claim_weak_request_tag)) {
+    oops_do_log_change("oops_do, mark weak done");
+    return NULL;
+  } else {
+    return old_head;
+  }
+}
+
+void nmethod::oops_do_add_to_list_as_strong_done() {
+  assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
+
+  nmethod* old_head = Atomic::xchg(this, &_oops_do_mark_nmethods);
+  // Self-loop if needed.
+  if (old_head == NULL) {
+    old_head = this;
+  }
+  assert(_oops_do_mark_link == mark_link(this, claim_strong_done_tag), "must be but is nmethod " PTR_FORMAT " state %u",
+         p2i(extract_nmethod(_oops_do_mark_link)), extract_state(_oops_do_mark_link));
+
+  oops_do_set_strong_done(old_head);
+}
+
+void nmethod::oops_do_process_weak(OopsDoProcessor* p) {
+  if (!oops_do_try_claim_weak_request()) {
+    // Failed to claim for weak processing.
+    oops_do_log_change("oops_do, mark weak request fail");
+    return;
+  }
+
+  p->do_regular_processing(this);
+
+  nmethod* old_head = oops_do_try_add_to_list_as_weak_done();
+  if (old_head == NULL) {
+    return;
+  }
+  oops_do_log_change("oops_do, mark weak done fail");
+  // Adding to global list failed, another thread added a strong request.
+  assert(extract_state(_oops_do_mark_link) == claim_strong_request_tag,
+         "must be but is %u", extract_state(_oops_do_mark_link));
+
+  oops_do_log_change("oops_do, mark weak request -> mark strong done");
+
+  oops_do_set_strong_done(old_head);
+  // Do missing strong processing.
+  p->do_remaining_strong_processing(this);
+}
+
+void nmethod::oops_do_process_strong(OopsDoProcessor* p) {
+  oops_do_mark_link* next_raw = oops_do_try_claim_strong_done();
+  if (next_raw == NULL) {
+    p->do_regular_processing(this);
+    oops_do_add_to_list_as_strong_done();
+    return;
+  }
+  // Claim failed. Figure out why and handle it.
+  if (oops_do_has_weak_request(next_raw)) {
+    oops_do_mark_link* old = next_raw;
+    // Claim failed because being weak processed (state == "weak request").
+    // Try to request deferred strong processing.
+    next_raw = oops_do_try_add_strong_request(old);
+    if (next_raw == old) {
+      // Successfully requested deferred strong processing.
+      return;
     }
+    // Failed because of a concurrent transition. No longer in "weak request" state.
   }
-  // On fall through, another racing thread marked this nmethod before we did.
-  return true;
+  if (oops_do_has_any_strong_state(next_raw)) {
+    // Already claimed for strong processing or requested for such.
+    return;
+  }
+  if (oops_do_try_claim_weak_done_as_strong_done(next_raw)) {
+    // Successfully claimed "weak done" as "strong done". Do the missing marking.
+    p->do_remaining_strong_processing(this);
+    return;
+  }
+  // Claim failed, some other thread got it.
 }
 
 void nmethod::oops_do_marking_prologue() {
+  assert_at_safepoint();
+
   log_trace(gc, nmethod)("oops_do_marking_prologue");
-  assert(_oops_do_mark_nmethods == NULL, "must not call oops_do_marking_prologue twice in a row");
-  // We use cmpxchg instead of regular assignment here because the user
-  // may fork a bunch of threads, and we need them all to see the same state.
-  nmethod* observed = Atomic::cmpxchg(NMETHOD_SENTINEL, &_oops_do_mark_nmethods, (nmethod*)NULL);
-  guarantee(observed == NULL, "no races in this sequential code");
+  assert(_oops_do_mark_nmethods == NULL, "must be empty");
 }
 
 void nmethod::oops_do_marking_epilogue() {
-  assert(_oops_do_mark_nmethods != NULL, "must not call oops_do_marking_epilogue twice in a row");
-  nmethod* cur = _oops_do_mark_nmethods;
-  while (cur != NMETHOD_SENTINEL) {
-    assert(cur != NULL, "not NULL-terminated");
-    nmethod* next = cur->_oops_do_mark_link;
+  assert_at_safepoint();
+
+  nmethod* next = _oops_do_mark_nmethods;
+  _oops_do_mark_nmethods = NULL;
+  if (next == NULL) {
+    return;
+  }
+  nmethod* cur;
+  do {
+    cur = next;
+    next = extract_nmethod(cur->_oops_do_mark_link);
     cur->_oops_do_mark_link = NULL;
     DEBUG_ONLY(cur->verify_oop_relocations());
 
@@ -1885,11 +2011,8 @@
       LogStream ls(lt);
       CompileTask::print(&ls, cur, "oops_do, unmark", /*short_form:*/ true);
     }
-    cur = next;
-  }
-  nmethod* required = _oops_do_mark_nmethods;
-  nmethod* observed = Atomic::cmpxchg((nmethod*)NULL, &_oops_do_mark_nmethods, required);
-  guarantee(observed == required, "no races in this sequential code");
+    // End if self-loop has been detected.
+  } while (cur != next);
   log_trace(gc, nmethod)("oops_do_marking_epilogue");
 }
 
@@ -2262,6 +2385,8 @@
   assert(voc.ok(), "embedded oops must be OK");
   Universe::heap()->verify_nmethod(this);
 
+  assert(_oops_do_mark_link == NULL, "_oops_do_mark_link for %s should be NULL but is " PTR_FORMAT,
+         nm->method()->external_name(), p2i(_oops_do_mark_link));
   verify_scopes();
 
   CompiledICLocker nm_verify(this);
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/code/nmethod.hpp
--- a/src/hotspot/share/code/nmethod.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/code/nmethod.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -67,8 +67,8 @@
   friend class NMethodSweeper;
   friend class CodeCache;  // scavengable oops
   friend class JVMCINMethodData;
+
  private:
-
   // Shared fields for all nmethod's
   int       _entry_bci;        // != InvocationEntryBci if this nmethod is an on-stack replacement method
   jmethodID _jmethod_id;       // Cache of method()->jmethod_id()
@@ -76,8 +76,119 @@
   // To support simple linked-list chaining of nmethods:
   nmethod*  _osr_link;         // from InstanceKlass::osr_nmethods_head
 
+  // STW two-phase nmethod root processing helpers.
+  //
+  // When determining liveness of a given nmethod to do code cache unloading,
+  // some collectors need to to different things depending on whether the nmethods
+  // need to absolutely be kept alive during root processing; "strong"ly reachable
+  // nmethods are known to be kept alive at root processing, but the liveness of
+  // "weak"ly reachable ones is to be determined later.
+  //
+  // We want to allow strong and weak processing of nmethods by different threads
+  // at the same time without heavy synchronization. Additional constraints are
+  // to make sure that every nmethod is processed a minimal amount of time, and
+  // nmethods themselves are always iterated at most once at a particular time.
+  //
+  // Note that strong processing work must be a superset of weak processing work
+  // for this code to work.
+  //
+  // We store state and claim information in the _oops_do_mark_link member, using
+  // the two LSBs for the state and the remaining upper bits for linking together
+  // nmethods that were already visited.
+  // The last element is self-looped, i.e. points to itself to avoid some special
+  // "end-of-list" sentinel value.
+  //
+  // _oops_do_mark_link special values:
+  //
+  //   _oops_do_mark_link == NULL: the nmethod has not been visited at all yet, i.e.
+  //      is Unclaimed.
+  //
+  // For other values, its lowest two bits indicate the following states of the nmethod:
+  //
+  //   weak_request (WR): the nmethod has been claimed by a thread for weak processing
+  //   weak_done (WD): weak processing has been completed for this nmethod.
+  //   strong_request (SR): the nmethod has been found to need strong processing while
+  //       being weak processed.
+  //   strong_done (SD): strong processing has been completed for this nmethod .
+  //
+  // The following shows the _only_ possible progressions of the _oops_do_mark_link
+  // pointer.
+  //
+  // Given
+  //   N as the nmethod
+  //   X the current next value of _oops_do_mark_link
+  //
+  // Unclaimed (C)-> N|WR (C)-> X|WD: the nmethod has been processed weakly by
+  //   a single thread.
+  // Unclaimed (C)-> N|WR (C)-> X|WD (O)-> X|SD: after weak processing has been
+  //   completed (as above) another thread found that the nmethod needs strong
+  //   processing after all.
+  // Unclaimed (C)-> N|WR (O)-> N|SR (C)-> X|SD: during weak processing another
+  //   thread finds that the nmethod needs strong processing, marks it as such and
+  //   terminates. The original thread completes strong processing.
+  // Unclaimed (C)-> N|SD (C)-> X|SD: the nmethod has been processed strongly from
+  //   the beginning by a single thread.
+  //
+  // "|" describes the concatentation of bits in _oops_do_mark_link.
+  //
+  // The diagram also describes the threads responsible for changing the nmethod to
+  // the next state by marking the _transition_ with (C) and (O), which mean "current"
+  // and "other" thread respectively.
+  //
+  struct oops_do_mark_link; // Opaque data type.
+
+  // States used for claiming nmethods during root processing.
+  static const uint claim_weak_request_tag = 0;
+  static const uint claim_weak_done_tag = 1;
+  static const uint claim_strong_request_tag = 2;
+  static const uint claim_strong_done_tag = 3;
+
+  static oops_do_mark_link* mark_link(nmethod* nm, uint tag) {
+    assert(tag <= claim_strong_done_tag, "invalid tag %u", tag);
+    assert(is_aligned(nm, 4), "nmethod pointer must have zero lower two LSB");
+    return (oops_do_mark_link*)(((uintptr_t)nm & ~0x3) | tag);
+  }
+
+  static uint extract_state(oops_do_mark_link* link) {
+    return (uint)((uintptr_t)link & 0x3);
+  }
+
+  static nmethod* extract_nmethod(oops_do_mark_link* link) {
+    return (nmethod*)((uintptr_t)link & ~0x3);
+  }
+
+  void oops_do_log_change(const char* state);
+
+  static bool oops_do_has_weak_request(oops_do_mark_link* next) {
+    return extract_state(next) == claim_weak_request_tag;
+  }
+
+  static bool oops_do_has_any_strong_state(oops_do_mark_link* next) {
+    return extract_state(next) >= claim_strong_request_tag;
+  }
+
+  // Attempt Unclaimed -> N|WR transition. Returns true if successful.
+  bool oops_do_try_claim_weak_request();
+
+  // Attempt Unclaimed -> N|SD transition. Returns the current link.
+  oops_do_mark_link* oops_do_try_claim_strong_done();
+  // Attempt N|WR -> X|WD transition. Returns NULL if successful, X otherwise.
+  nmethod* oops_do_try_add_to_list_as_weak_done();
+
+  // Attempt X|WD -> N|SR transition. Returns the current link.
+  oops_do_mark_link* oops_do_try_add_strong_request(oops_do_mark_link* next);
+  // Attempt X|WD -> X|SD transition. Returns true if successful.
+  bool oops_do_try_claim_weak_done_as_strong_done(oops_do_mark_link* next);
+
+  // Do the N|SD -> X|SD transition.
+  void oops_do_add_to_list_as_strong_done();
+
+  // Sets this nmethod as strongly claimed (as part of N|SD -> X|SD and N|SR -> X|SD
+  // transitions).
+  void oops_do_set_strong_done(nmethod* old_head);
+
   static nmethod* volatile _oops_do_mark_nmethods;
-  nmethod*        volatile _oops_do_mark_link;
+  oops_do_mark_link* volatile _oops_do_mark_link;
 
   // offsets for entry points
   address _entry_point;                      // entry point with class check
@@ -480,11 +591,30 @@
   void oops_do(OopClosure* f) { oops_do(f, false); }
   void oops_do(OopClosure* f, bool allow_dead);
 
-  bool test_set_oops_do_mark();
+  // All-in-one claiming of nmethods: returns true if the caller successfully claimed that
+  // nmethod.
+  bool oops_do_try_claim();
+
+  // Class containing callbacks for the oops_do_process_weak/strong() methods
+  // below.
+  class OopsDoProcessor {
+  public:
+    // Process the oops of the given nmethod based on whether it has been called
+    // in a weak or strong processing context, i.e. apply either weak or strong
+    // work on it.
+    virtual void do_regular_processing(nmethod* nm) = 0;
+    // Assuming that the oops of the given nmethod has already been its weak
+    // processing applied, apply the remaining strong processing part.
+    virtual void do_remaining_strong_processing(nmethod* nm) = 0;
+  };
+
+  // The following two methods do the work corresponding to weak/strong nmethod
+  // processing.
+  void oops_do_process_weak(OopsDoProcessor* p);
+  void oops_do_process_strong(OopsDoProcessor* p);
+
   static void oops_do_marking_prologue();
   static void oops_do_marking_epilogue();
-  static bool oops_do_marking_is_active() { return _oops_do_mark_nmethods != NULL; }
-  bool test_oops_do_mark() { return _oops_do_mark_link != NULL; }
 
  private:
   ScopeDesc* scope_desc_in(address begin, address end);
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/compiler/oopMap.cpp
--- a/src/hotspot/share/compiler/oopMap.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/compiler/oopMap.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -308,10 +308,13 @@
 
   // handle derived pointers first (otherwise base pointer may be
   // changed before derived pointer offset has been collected)
-  OopMapValue omv;
   {
-    OopMapStream oms(map);
-    if (!oms.is_done()) {
+    for (OopMapStream oms(map); !oms.is_done(); oms.next()) {
+      OopMapValue omv = oms.current();
+      if (omv.type() != OopMapValue::derived_oop_value) {
+        continue;
+      }
+
 #ifndef TIERED
       COMPILER1_PRESENT(ShouldNotReachHere();)
 #if INCLUDE_JVMCI
@@ -320,31 +323,25 @@
       }
 #endif
 #endif // !TIERED
-      do {
-        omv = oms.current();
-        if (omv.type() == OopMapValue::derived_oop_value) {
-          oop* loc = fr->oopmapreg_to_location(omv.reg(),reg_map);
-          guarantee(loc != NULL, "missing saved register");
-          oop *derived_loc = loc;
-          oop *base_loc    = fr->oopmapreg_to_location(omv.content_reg(), reg_map);
-          // Ignore NULL oops and decoded NULL narrow oops which
-          // equal to CompressedOops::base() when a narrow oop
-          // implicit null check is used in compiled code.
-          // The narrow_oop_base could be NULL or be the address
-          // of the page below heap depending on compressed oops mode.
-          if (base_loc != NULL && *base_loc != NULL && !CompressedOops::is_base(*base_loc)) {
-            derived_oop_fn(base_loc, derived_loc);
-          }
-        }
-        oms.next();
-      }  while (!oms.is_done());
+      oop* loc = fr->oopmapreg_to_location(omv.reg(),reg_map);
+      guarantee(loc != NULL, "missing saved register");
+      oop *derived_loc = loc;
+      oop *base_loc    = fr->oopmapreg_to_location(omv.content_reg(), reg_map);
+      // Ignore NULL oops and decoded NULL narrow oops which
+      // equal to CompressedOops::base() when a narrow oop
+      // implicit null check is used in compiled code.
+      // The narrow_oop_base could be NULL or be the address
+      // of the page below heap depending on compressed oops mode.
+      if (base_loc != NULL && *base_loc != NULL && !CompressedOops::is_base(*base_loc)) {
+        derived_oop_fn(base_loc, derived_loc);
+      }
     }
   }
 
   {
     // We want coop and oop oop_types
     for (OopMapStream oms(map); !oms.is_done(); oms.next()) {
-      omv = oms.current();
+      OopMapValue omv = oms.current();
       oop* loc = fr->oopmapreg_to_location(omv.reg(),reg_map);
       // It should be an error if no location can be found for a
       // register mentioned as contained an oop of some kind.  Maybe
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/g1/g1Analytics.cpp
--- a/src/hotspot/share/gc/g1/g1Analytics.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/g1/g1Analytics.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -229,10 +229,6 @@
   _rs_length_seq->add(rs_length);
 }
 
-size_t G1Analytics::predict_rs_length_diff() const {
-  return get_new_size_prediction(_rs_length_diff_seq);
-}
-
 double G1Analytics::predict_alloc_rate_ms() const {
   return get_new_prediction(_alloc_rate_ms_seq);
 }
@@ -334,7 +330,7 @@
 }
 
 size_t G1Analytics::predict_rs_length() const {
-  return get_new_size_prediction(_rs_length_seq);
+  return get_new_size_prediction(_rs_length_seq) + get_new_prediction(_rs_length_diff_seq);
 }
 
 size_t G1Analytics::predict_pending_cards() const {
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/g1/g1Analytics.hpp
--- a/src/hotspot/share/gc/g1/g1Analytics.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/g1/g1Analytics.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -115,8 +115,6 @@
   void report_pending_cards(double pending_cards);
   void report_rs_length(double rs_length);
 
-  size_t predict_rs_length_diff() const;
-
   double predict_alloc_rate_ms() const;
   int num_alloc_rate_ms() const;
 
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/g1/g1CodeBlobClosure.cpp
--- a/src/hotspot/share/gc/g1/g1CodeBlobClosure.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/g1/g1CodeBlobClosure.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -26,6 +26,7 @@
 #include "code/nmethod.hpp"
 #include "gc/g1/g1CodeBlobClosure.hpp"
 #include "gc/g1/g1CollectedHeap.inline.hpp"
+#include "gc/g1/g1ConcurrentMark.inline.hpp"
 #include "gc/g1/heapRegion.hpp"
 #include "gc/g1/heapRegionRemSet.hpp"
 #include "oops/access.inline.hpp"
@@ -52,14 +53,62 @@
   do_oop_work(o);
 }
 
-void G1CodeBlobClosure::do_code_blob(CodeBlob* cb) {
-  nmethod* nm = cb->as_nmethod_or_null();
-  if (nm != NULL) {
-    if (!nm->test_set_oops_do_mark()) {
-      _oc.set_nm(nm);
-      nm->oops_do(&_oc);
-      nm->fix_oop_relocations();
-    }
+template<typename T>
+void G1CodeBlobClosure::MarkingOopClosure::do_oop_work(T* p) {
+  T oop_or_narrowoop = RawAccess<>::oop_load(p);
+  if (!CompressedOops::is_null(oop_or_narrowoop)) {
+    oop o = CompressedOops::decode_not_null(oop_or_narrowoop);
+    _cm->mark_in_next_bitmap(_worker_id, o);
   }
 }
 
+G1CodeBlobClosure::MarkingOopClosure::MarkingOopClosure(uint worker_id) :
+  _cm(G1CollectedHeap::heap()->concurrent_mark()), _worker_id(worker_id) { }
+
+void G1CodeBlobClosure::MarkingOopClosure::do_oop(oop* o) {
+  do_oop_work(o);
+}
+
+void G1CodeBlobClosure::MarkingOopClosure::do_oop(narrowOop* o) {
+  do_oop_work(o);
+}
+
+void G1CodeBlobClosure::do_evacuation_and_fixup(nmethod* nm) {
+  _oc.set_nm(nm);
+  nm->oops_do(&_oc);
+  nm->fix_oop_relocations();
+}
+
+void G1CodeBlobClosure::do_marking(nmethod* nm) {
+  nm->oops_do(&_marking_oc);
+}
+
+class G1NmethodProcessor : public nmethod::OopsDoProcessor {
+  G1CodeBlobClosure* _cl;
+
+public:
+  G1NmethodProcessor(G1CodeBlobClosure* cl) : _cl(cl) { }
+
+  void do_regular_processing(nmethod* nm) {
+    _cl->do_evacuation_and_fixup(nm);
+  }
+
+  void do_remaining_strong_processing(nmethod* nm) {
+    _cl->do_marking(nm);
+  }
+};
+
+void G1CodeBlobClosure::do_code_blob(CodeBlob* cb) {
+  nmethod* nm = cb->as_nmethod_or_null();
+  if (nm == NULL) {
+    return;
+  }
+
+  G1NmethodProcessor cl(this);
+
+  if (_strong) {
+    nm->oops_do_process_strong(&cl);
+  } else {
+    nm->oops_do_process_weak(&cl);
+  }
+}
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/g1/g1CodeBlobClosure.hpp
--- a/src/hotspot/share/gc/g1/g1CodeBlobClosure.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/g1/g1CodeBlobClosure.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -28,9 +28,11 @@
 #include "gc/g1/g1CollectedHeap.hpp"
 #include "memory/iterator.hpp"
 
+class G1ConcurrentMark;
 class nmethod;
 
 class G1CodeBlobClosure : public CodeBlobClosure {
+  // Gather nmethod remembered set entries.
   class HeapRegionGatheringOopClosure : public OopClosure {
     G1CollectedHeap* _g1h;
     OopClosure* _work;
@@ -50,9 +52,35 @@
     }
   };
 
+  // Mark all oops below TAMS.
+  class MarkingOopClosure : public OopClosure {
+    G1ConcurrentMark* _cm;
+    uint _worker_id;
+
+    template <typename T>
+    void do_oop_work(T* p);
+
+  public:
+    MarkingOopClosure(uint worker_id);
+
+    void do_oop(oop* o);
+    void do_oop(narrowOop* o);
+  };
+
   HeapRegionGatheringOopClosure _oc;
+  MarkingOopClosure _marking_oc;
+
+  bool _strong;
+
+  void do_code_blob_weak(CodeBlob* cb);
+  void do_code_blob_strong(CodeBlob* cb);
+
 public:
-  G1CodeBlobClosure(OopClosure* oc) : _oc(oc) {}
+  G1CodeBlobClosure(uint worker_id, OopClosure* oc, bool strong) :
+    _oc(oc), _marking_oc(worker_id), _strong(strong) { }
+
+  void do_evacuation_and_fixup(nmethod* nm);
+  void do_marking(nmethod* nm);
 
   void do_code_blob(CodeBlob* cb);
 };
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/g1/g1CollectedHeap.cpp
--- a/src/hotspot/share/gc/g1/g1CollectedHeap.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/g1/g1CollectedHeap.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -4098,7 +4098,7 @@
     _cl.complete_work();
 
     G1Policy* policy = G1CollectedHeap::heap()->policy();
-    policy->record_max_rs_length(_rs_length);
+    policy->record_rs_length(_rs_length);
     policy->cset_regions_freed();
   }
 public:
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/g1/g1FullCollector.cpp
--- a/src/hotspot/share/gc/g1/g1FullCollector.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/g1/g1FullCollector.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -198,13 +198,17 @@
   // Recursively traverse all live objects and mark them.
   GCTraceTime(Info, gc, phases) info("Phase 1: Mark live objects", scope()->timer());
 
-  // Do the actual marking.
-  G1FullGCMarkTask marking_task(this);
-  run_task(&marking_task);
+  {
+    // Do the actual marking.
+    G1FullGCMarkTask marking_task(this);
+    run_task(&marking_task);
+  }
 
-  // Process references discovered during marking.
-  G1FullGCReferenceProcessingExecutor reference_processing(this);
-  reference_processing.execute(scope()->timer(), scope()->tracer());
+  {
+    // Process references discovered during marking.
+    G1FullGCReferenceProcessingExecutor reference_processing(this);
+    reference_processing.execute(scope()->timer(), scope()->tracer());
+  }
 
   // Weak oops cleanup.
   {
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/g1/g1GCPhaseTimes.cpp
--- a/src/hotspot/share/gc/g1/g1GCPhaseTimes.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/g1/g1GCPhaseTimes.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -62,7 +62,6 @@
   _gc_par_phases[JVMTIRoots] = new WorkerDataArray<double>(max_gc_threads, "JVMTI Roots (ms):");
   AOT_ONLY(_gc_par_phases[AOTCodeRoots] = new WorkerDataArray<double>(max_gc_threads, "AOT Root Scan (ms):");)
   _gc_par_phases[CMRefRoots] = new WorkerDataArray<double>(max_gc_threads, "CM RefProcessor Roots (ms):");
-  _gc_par_phases[WaitForStrongRoots] = new WorkerDataArray<double>(max_gc_threads, "Wait For Strong Roots (ms):");
 
   _gc_par_phases[MergeER] = new WorkerDataArray<double>(max_gc_threads, "Eager Reclaim (ms):");
 
@@ -165,7 +164,7 @@
 
 void G1GCPhaseTimes::reset() {
   _cur_collection_initial_evac_time_ms = 0.0;
-  _cur_optional_evac_ms = 0.0;
+  _cur_optional_evac_time_ms = 0.0;
   _cur_collection_code_root_fixup_time_ms = 0.0;
   _cur_strong_code_root_purge_time_ms = 0.0;
   _cur_merge_heap_roots_time_ms = 0.0;
@@ -417,14 +416,14 @@
 }
 
 double G1GCPhaseTimes::print_evacuate_optional_collection_set() const {
-  const double sum_ms = _cur_optional_evac_ms + _cur_optional_merge_heap_roots_time_ms;
+  const double sum_ms = _cur_optional_evac_time_ms + _cur_optional_merge_heap_roots_time_ms;
   if (sum_ms > 0) {
     info_time("Merge Optional Heap Roots", _cur_optional_merge_heap_roots_time_ms);
 
     debug_time("Prepare Optional Merge Heap Roots", _cur_optional_prepare_merge_heap_roots_time_ms);
     debug_phase(_gc_par_phases[OptMergeRS]);
 
-    info_time("Evacuate Optional Collection Set", _cur_optional_evac_ms);
+    info_time("Evacuate Optional Collection Set", _cur_optional_evac_time_ms);
     debug_phase(_gc_par_phases[OptScanHR]);
     debug_phase(_gc_par_phases[OptObjCopy]);
     debug_phase(_gc_par_phases[OptCodeRoots]);
@@ -566,7 +565,6 @@
       "JVMTIRoots",
       AOT_ONLY("AOTCodeRoots" COMMA)
       "CMRefRoots",
-      "WaitForStrongRoots",
       "MergeER",
       "MergeRS",
       "OptMergeRS",
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/g1/g1GCPhaseTimes.hpp
--- a/src/hotspot/share/gc/g1/g1GCPhaseTimes.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/g1/g1GCPhaseTimes.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -57,7 +57,6 @@
     JVMTIRoots,
     AOT_ONLY(AOTCodeRoots COMMA)
     CMRefRoots,
-    WaitForStrongRoots,
     MergeER,
     MergeRS,
     OptMergeRS,
@@ -83,7 +82,7 @@
   };
 
   static const GCParPhases ExtRootScanSubPhasesFirst = ThreadRoots;
-  static const GCParPhases ExtRootScanSubPhasesLast = WaitForStrongRoots;
+  static const GCParPhases ExtRootScanSubPhasesLast = CMRefRoots;
 
   enum GCMergeRSWorkTimes {
     MergeRSMergedSparse,
@@ -157,7 +156,7 @@
   WorkerDataArray<size_t>* _redirtied_cards;
 
   double _cur_collection_initial_evac_time_ms;
-  double _cur_optional_evac_ms;
+  double _cur_optional_evac_time_ms;
   double _cur_collection_code_root_fixup_time_ms;
   double _cur_strong_code_root_purge_time_ms;
 
@@ -297,7 +296,7 @@
   }
 
   void record_or_add_optional_evac_time(double ms) {
-    _cur_optional_evac_ms += ms;
+    _cur_optional_evac_time_ms += ms;
   }
 
   void record_or_add_code_root_fixup_time(double ms) {
@@ -416,7 +415,7 @@
   }
 
   double cur_collection_par_time_ms() {
-    return _cur_collection_initial_evac_time_ms;
+    return _cur_collection_initial_evac_time_ms + _cur_optional_evac_time_ms;
   }
 
   double cur_clear_ct_time_ms() {
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/g1/g1Policy.cpp
--- a/src/hotspot/share/gc/g1/g1Policy.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/g1/g1Policy.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -68,7 +68,7 @@
   _reserve_regions(0),
   _young_gen_sizer(G1YoungGenSizer::create_gen_sizer()),
   _free_regions_at_end_of_collection(0),
-  _max_rs_length(0),
+  _rs_length(0),
   _rs_length_prediction(0),
   _pending_cards_at_gc_start(0),
   _pending_cards_at_prev_gc_end(0),
@@ -330,8 +330,7 @@
   const double target_pause_time_ms = _mmu_tracker->max_gc_time() * 1000.0;
   const double survivor_regions_evac_time = predict_survivor_regions_evac_time();
   const size_t pending_cards = _analytics->predict_pending_cards();
-  const size_t adj_rs_length = rs_length + _analytics->predict_rs_length_diff();
-  const size_t scanned_cards = _analytics->predict_card_num(adj_rs_length, true /* for_young_gc */);
+  const size_t scanned_cards = _analytics->predict_card_num(rs_length, true /* for_young_gc */);
   const double base_time_ms =
     predict_base_elapsed_time_ms(pending_cards, scanned_cards) +
     survivor_regions_evac_time;
@@ -753,13 +752,13 @@
       _analytics->report_cost_per_remset_card_ms(cost_per_remset_card_ms, this_pause_was_young_only);
     }
 
-    if (_max_rs_length > 0) {
+    if (_rs_length > 0) {
       double cards_per_entry_ratio =
-        (double) remset_cards_scanned / (double) _max_rs_length;
+        (double) remset_cards_scanned / (double) _rs_length;
       _analytics->report_cards_per_entry_ratio(cards_per_entry_ratio, this_pause_was_young_only);
     }
 
-    // This is defensive. For a while _max_rs_length could get
+    // This is defensive. For a while _rs_length could get
     // smaller than _recorded_rs_length which was causing
     // rs_length_diff to get very large and mess up the RSet length
     // predictions. The reason was unsafe concurrent updates to the
@@ -774,8 +773,8 @@
     // conditional below just in case.
     size_t rs_length_diff = 0;
     size_t recorded_rs_length = _collection_set->recorded_rs_length();
-    if (_max_rs_length > recorded_rs_length) {
-      rs_length_diff = _max_rs_length - recorded_rs_length;
+    if (_rs_length > recorded_rs_length) {
+      rs_length_diff = _rs_length - recorded_rs_length;
     }
     _analytics->report_rs_length_diff((double) rs_length_diff);
 
@@ -806,7 +805,7 @@
     // During mixed gc we do not use them for young gen sizing.
     if (this_pause_was_young_only) {
       _analytics->report_pending_cards((double) _pending_cards_at_gc_start);
-      _analytics->report_rs_length((double) _max_rs_length);
+      _analytics->report_rs_length((double) _rs_length);
     }
   }
 
@@ -951,7 +950,7 @@
 }
 
 double G1Policy::predict_base_elapsed_time_ms(size_t pending_cards) const {
-  size_t rs_length = _analytics->predict_rs_length() + _analytics->predict_rs_length_diff();
+  size_t rs_length = _analytics->predict_rs_length();
   size_t card_num = _analytics->predict_card_num(rs_length, collector_state()->in_young_only_phase());
   return predict_base_elapsed_time_ms(pending_cards, card_num);
 }
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/g1/g1Policy.hpp
--- a/src/hotspot/share/gc/g1/g1Policy.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/g1/g1Policy.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -96,7 +96,7 @@
 
   uint _free_regions_at_end_of_collection;
 
-  size_t _max_rs_length;
+  size_t _rs_length;
 
   size_t _rs_length_prediction;
 
@@ -136,8 +136,8 @@
     hr->install_surv_rate_group(_survivor_surv_rate_group);
   }
 
-  void record_max_rs_length(size_t rs_length) {
-    _max_rs_length = rs_length;
+  void record_rs_length(size_t rs_length) {
+    _rs_length = rs_length;
   }
 
   double predict_base_elapsed_time_ms(size_t pending_cards) const;
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/g1/g1RootClosures.cpp
--- a/src/hotspot/share/gc/g1/g1RootClosures.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/g1/g1RootClosures.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -45,8 +45,6 @@
 
   CodeBlobClosure* strong_codeblobs()      { return &_closures._codeblobs; }
   CodeBlobClosure* weak_codeblobs()        { return &_closures._codeblobs; }
-
-  bool trace_metadata()         { return false; }
 };
 
 // Closures used during initial mark.
@@ -71,10 +69,6 @@
 
   CodeBlobClosure* strong_codeblobs()      { return &_strong._codeblobs; }
   CodeBlobClosure* weak_codeblobs()        { return &_weak._codeblobs; }
-
-  // If we are not marking all weak roots then we are tracing
-  // which metadata is alive.
-  bool trace_metadata()         { return MarkWeak == G1MarkPromotedFromRoot; }
 };
 
 G1EvacuationRootClosures* G1EvacuationRootClosures::create_root_closures(G1ParScanThreadState* pss, G1CollectedHeap* g1h) {
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/g1/g1RootClosures.hpp
--- a/src/hotspot/share/gc/g1/g1RootClosures.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/g1/g1RootClosures.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -52,9 +52,6 @@
   // Applied to code blobs treated as weak roots.
   virtual CodeBlobClosure* weak_codeblobs() = 0;
 
-  // Is this closure used for tracing metadata?
-  virtual bool trace_metadata() = 0;
-
   static G1EvacuationRootClosures* create_root_closures(G1ParScanThreadState* pss, G1CollectedHeap* g1h);
 };
 
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/g1/g1RootProcessor.cpp
--- a/src/hotspot/share/gc/g1/g1RootProcessor.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/g1/g1RootProcessor.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -45,34 +45,10 @@
 #include "services/management.hpp"
 #include "utilities/macros.hpp"
 
-void G1RootProcessor::worker_has_discovered_all_strong_nmethods() {
-  assert(ClassUnloadingWithConcurrentMark, "Currently only needed when doing G1 Class Unloading");
-
-  uint new_value = (uint)Atomic::add(1, &_n_workers_discovered_strong_classes);
-  if (new_value == n_workers()) {
-    // This thread is last. Notify the others.
-    MonitorLocker ml(&_lock, Mutex::_no_safepoint_check_flag);
-    _lock.notify_all();
-  }
-}
-
-void G1RootProcessor::wait_until_all_strong_nmethods_discovered() {
-  assert(ClassUnloadingWithConcurrentMark, "Currently only needed when doing G1 Class Unloading");
-
-  if ((uint)_n_workers_discovered_strong_classes != n_workers()) {
-    MonitorLocker ml(&_lock, Mutex::_no_safepoint_check_flag);
-    while ((uint)_n_workers_discovered_strong_classes != n_workers()) {
-      ml.wait(0);
-    }
-  }
-}
-
 G1RootProcessor::G1RootProcessor(G1CollectedHeap* g1h, uint n_workers) :
     _g1h(g1h),
     _process_strong_tasks(G1RP_PS_NumElements),
-    _srs(n_workers),
-    _lock(Mutex::leaf, "G1 Root Scan barrier lock", false, Mutex::_safepoint_check_never),
-    _n_workers_discovered_strong_classes(0) {}
+    _srs(n_workers) {}
 
 void G1RootProcessor::evacuate_roots(G1ParScanThreadState* pss, uint worker_id) {
   G1GCPhaseTimes* phase_times = _g1h->phase_times();
@@ -80,7 +56,7 @@
   G1EvacPhaseTimesTracker timer(phase_times, pss, G1GCPhaseTimes::ExtRootScan, worker_id);
 
   G1EvacuationRootClosures* closures = pss->closures();
-  process_java_roots(closures, phase_times, worker_id, closures->trace_metadata() /* notify_claimed_nmethods_done */);
+  process_java_roots(closures, phase_times, worker_id);
 
   process_vm_roots(closures, phase_times, worker_id);
 
@@ -96,12 +72,6 @@
     }
   }
 
-  if (closures->trace_metadata()) {
-    G1GCParPhaseTimesTracker x(phase_times, G1GCPhaseTimes::WaitForStrongRoots, worker_id);
-    // Wait to make sure all workers passed the strong nmethods phase.
-    wait_until_all_strong_nmethods_discovered();
-  }
-
   _process_strong_tasks.all_tasks_completed(n_workers());
 }
 
@@ -171,8 +141,7 @@
 
 void G1RootProcessor::process_java_roots(G1RootClosures* closures,
                                          G1GCPhaseTimes* phase_times,
-                                         uint worker_id,
-                                         bool notify_claimed_nmethods_done) {
+                                         uint worker_id) {
   // We need to make make sure that the "strong" nmethods are processed first
   // using the strong closure. Only after that we process the weakly reachable
   // nmethods.
@@ -197,12 +166,6 @@
                                        closures->strong_codeblobs());
   }
 
-  // This is the point where this worker thread will not find more strong nmethods.
-  // Report this so G1 can synchronize the strong and weak CLDs/nmethods processing.
-  if (notify_claimed_nmethods_done) {
-    worker_has_discovered_all_strong_nmethods();
-  }
-
   {
     G1GCParPhaseTimesTracker x(phase_times, G1GCPhaseTimes::CLDGRoots, worker_id);
     if (_process_strong_tasks.try_claim_task(G1RP_PS_ClassLoaderDataGraph_oops_do)) {
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/g1/g1RootProcessor.hpp
--- a/src/hotspot/share/gc/g1/g1RootProcessor.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/g1/g1RootProcessor.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -50,10 +50,6 @@
   SubTasksDone _process_strong_tasks;
   StrongRootsScope _srs;
 
-  // Used to implement the Thread work barrier.
-  Monitor _lock;
-  volatile jint _n_workers_discovered_strong_classes;
-
   enum G1H_process_roots_tasks {
     G1RP_PS_Universe_oops_do,
     G1RP_PS_JNIHandles_oops_do,
@@ -69,13 +65,9 @@
     G1RP_PS_NumElements
   };
 
-  void worker_has_discovered_all_strong_nmethods();
-  void wait_until_all_strong_nmethods_discovered();
-
   void process_java_roots(G1RootClosures* closures,
                           G1GCPhaseTimes* phase_times,
-                          uint worker_id,
-                          bool notify_claimed_nmethods_done = false);
+                          uint worker_id);
 
   void process_vm_roots(G1RootClosures* closures,
                         G1GCPhaseTimes* phase_times,
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/g1/g1SharedClosures.hpp
--- a/src/hotspot/share/gc/g1/g1SharedClosures.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/g1/g1SharedClosures.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -32,6 +32,11 @@
 // Simple holder object for a complete set of closures used by the G1 evacuation code.
 template <G1Mark Mark>
 class G1SharedClosures {
+  static bool needs_strong_processing() {
+    // Request strong code root processing when G1MarkFromRoot is passed in during
+    // initial mark.
+    return Mark == G1MarkFromRoot;
+  }
 public:
   G1ParCopyClosure<G1BarrierNone, Mark> _oops;
   G1ParCopyClosure<G1BarrierCLD,  Mark> _oops_in_cld;
@@ -43,5 +48,5 @@
     _oops(g1h, pss),
     _oops_in_cld(g1h, pss),
     _clds(&_oops_in_cld, process_only_dirty),
-    _codeblobs(&_oops) {}
+    _codeblobs(pss->worker_id(), &_oops, needs_strong_processing()) {}
 };
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/shenandoah/c2/shenandoahBarrierSetC2.cpp
--- a/src/hotspot/share/gc/shenandoah/c2/shenandoahBarrierSetC2.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/shenandoah/c2/shenandoahBarrierSetC2.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -297,8 +297,15 @@
 }
 
 bool ShenandoahBarrierSetC2::is_shenandoah_lrb_call(Node* call) {
-  return call->is_CallLeaf() &&
-          call->as_CallLeaf()->entry_point() == CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier);
+  if (!call->is_CallLeaf()) {
+    return false;
+  }
+
+  address entry_point = call->as_CallLeaf()->entry_point();
+  return (entry_point == CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier)) ||
+         (entry_point == CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_fixup)) ||
+         (entry_point == CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_fixup_narrow)) ||
+         (entry_point == CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_native));
 }
 
 bool ShenandoahBarrierSetC2::is_shenandoah_marking_if(PhaseTransform *phase, Node* n) {
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/shenandoah/heuristics/shenandoahCompactHeuristics.cpp
--- a/src/hotspot/share/gc/shenandoah/heuristics/shenandoahCompactHeuristics.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/shenandoah/heuristics/shenandoahCompactHeuristics.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -65,13 +65,6 @@
     return true;
   }
 
-  if (available < threshold_bytes_allocated) {
-    log_info(gc)("Trigger: Free (" SIZE_FORMAT "%s) is lower than allocated recently (" SIZE_FORMAT "%s)",
-                 byte_size_in_proper_unit(available),                 proper_unit_for_byte_size(available),
-                 byte_size_in_proper_unit(threshold_bytes_allocated), proper_unit_for_byte_size(threshold_bytes_allocated));
-    return true;
-  }
-
   size_t bytes_allocated = heap->bytes_allocated_since_gc_start();
   if (bytes_allocated > threshold_bytes_allocated) {
     log_info(gc)("Trigger: Allocated since last cycle (" SIZE_FORMAT "%s) is larger than allocation threshold (" SIZE_FORMAT "%s)",
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/z/zAddressSpaceLimit.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/gc/z/zAddressSpaceLimit.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -0,0 +1,51 @@
+/*
+ * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+#include "precompiled.hpp"
+#include "gc/z/zAddressSpaceLimit.hpp"
+#include "gc/z/zGlobals.hpp"
+#include "runtime/os.hpp"
+#include "utilities/align.hpp"
+
+static size_t address_space_limit() {
+  julong limit = 0;
+
+  if (os::has_allocatable_memory_limit(&limit)) {
+    return (size_t)limit;
+  }
+
+  // No limit
+  return SIZE_MAX;
+}
+
+size_t ZAddressSpaceLimit::mark_stack() {
+  // Allow mark stacks to occupy 10% of the address space
+  const size_t limit = address_space_limit() / 10;
+  return align_up(limit, ZMarkStackSpaceExpandSize);
+}
+
+size_t ZAddressSpaceLimit::heap_view() {
+  // Allow all heap views to occupy 50% of the address space
+  const size_t limit = address_space_limit() / 2 / ZHeapViews;
+  return align_up(limit, ZGranuleSize);
+}
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/z/zAddressSpaceLimit.hpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/gc/z/zAddressSpaceLimit.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -0,0 +1,35 @@
+/*
+ * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+#ifndef SHARE_GC_Z_ZADDRESSSPACELIMIT_HPP
+#define SHARE_GC_Z_ZADDRESSSPACELIMIT_HPP
+
+#include "memory/allocation.hpp"
+
+class ZAddressSpaceLimit : public AllStatic {
+public:
+  static size_t mark_stack();
+  static size_t heap_view();
+};
+
+#endif // SHARE_GC_Z_ZADDRESSSPACELIMIT_HPP
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/z/zArguments.cpp
--- a/src/hotspot/share/gc/z/zArguments.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/z/zArguments.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -22,6 +22,7 @@
  */
 
 #include "precompiled.hpp"
+#include "gc/z/zAddressSpaceLimit.hpp"
 #include "gc/z/zArguments.hpp"
 #include "gc/z/zCollectedHeap.hpp"
 #include "gc/z/zWorkers.hpp"
@@ -37,6 +38,15 @@
 void ZArguments::initialize() {
   GCArguments::initialize();
 
+  // Check mark stack size
+  const size_t mark_stack_space_limit = ZAddressSpaceLimit::mark_stack();
+  if (ZMarkStackSpaceLimit > mark_stack_space_limit) {
+    if (!FLAG_IS_DEFAULT(ZMarkStackSpaceLimit)) {
+      vm_exit_during_initialization("ZMarkStackSpaceLimit too large for limited address space");
+    }
+    FLAG_SET_DEFAULT(ZMarkStackSpaceLimit, mark_stack_space_limit);
+  }
+
   // Enable NUMA by default
   if (FLAG_IS_DEFAULT(UseNUMA)) {
     FLAG_SET_DEFAULT(UseNUMA, true);
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/z/zForwardingTable.cpp
--- a/src/hotspot/share/gc/z/zForwardingTable.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/z/zForwardingTable.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -22,27 +22,27 @@
  */
 
 #include "precompiled.hpp"
-#include "gc/z/zAddress.inline.hpp"
 #include "gc/z/zForwarding.inline.hpp"
 #include "gc/z/zForwardingTable.inline.hpp"
+#include "gc/z/zGlobals.hpp"
 #include "gc/z/zGranuleMap.inline.hpp"
 #include "utilities/debug.hpp"
 
 ZForwardingTable::ZForwardingTable() :
-    _map() {}
+    _map(ZAddressOffsetMax) {}
 
 void ZForwardingTable::insert(ZForwarding* forwarding) {
-  const uintptr_t addr = ZAddress::good(forwarding->start());
+  const uintptr_t offset = forwarding->start();
   const size_t size = forwarding->size();
 
-  assert(get(addr) == NULL, "Invalid entry");
-  _map.put(addr, size, forwarding);
+  assert(_map.get(offset) == NULL, "Invalid entry");
+  _map.put(offset, size, forwarding);
 }
 
 void ZForwardingTable::remove(ZForwarding* forwarding) {
-  const uintptr_t addr = ZAddress::good(forwarding->start());
+  const uintptr_t offset = forwarding->start();
   const size_t size = forwarding->size();
 
-  assert(get(addr) == forwarding, "Invalid entry");
-  _map.put(addr, size, NULL);
+  assert(_map.get(offset) == forwarding, "Invalid entry");
+  _map.put(offset, size, NULL);
 }
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/z/zForwardingTable.inline.hpp
--- a/src/hotspot/share/gc/z/zForwardingTable.inline.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/z/zForwardingTable.inline.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -24,11 +24,13 @@
 #ifndef SHARE_GC_Z_ZFORWARDINGTABLE_INLINE_HPP
 #define SHARE_GC_Z_ZFORWARDINGTABLE_INLINE_HPP
 
+#include "gc/z/zAddress.inline.hpp"
 #include "gc/z/zForwardingTable.hpp"
 #include "gc/z/zGranuleMap.inline.hpp"
 
 inline ZForwarding* ZForwardingTable::get(uintptr_t addr) const {
-  return _map.get(addr);
+  assert(!ZAddress::is_null(addr), "Invalid address");
+  return _map.get(ZAddress::offset(addr));
 }
 
 #endif // SHARE_GC_Z_ZFORWARDINGTABLE_INLINE_HPP
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/z/zFuture.hpp
--- a/src/hotspot/share/gc/z/zFuture.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/z/zFuture.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015, 2017, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2015, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -34,7 +34,10 @@
   T         _value;
 
 public:
+  ZFuture();
+
   void set(T value);
+  T peek();
   T get();
 };
 
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/z/zFuture.inline.hpp
--- a/src/hotspot/share/gc/z/zFuture.inline.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/z/zFuture.inline.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -29,6 +29,10 @@
 #include "runtime/thread.hpp"
 
 template <typename T>
+inline ZFuture<T>::ZFuture() :
+    _value() {}
+
+template <typename T>
 inline void ZFuture<T>::set(T value) {
   // Set value
   _value = value;
@@ -38,6 +42,11 @@
 }
 
 template <typename T>
+inline T ZFuture<T>::peek() {
+  return _value;
+}
+
+template <typename T>
 inline T ZFuture<T>::get() {
   // Wait for notification
   Thread* const thread = Thread::current();
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/z/zGlobals.hpp
--- a/src/hotspot/share/gc/z/zGlobals.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/z/zGlobals.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -44,6 +44,23 @@
 const size_t      ZGranuleSizeShift             = ZPlatformGranuleSizeShift;
 const size_t      ZGranuleSize                  = (size_t)1 << ZGranuleSizeShift;
 
+// Number of heap views
+const size_t      ZHeapViews                    = ZPlatformHeapViews;
+
+// Virtual memory to physical memory ratio
+const size_t      ZVirtualToPhysicalRatio       = 16; // 16:1
+
+//
+// Page Tiers (assuming ZGranuleSize=2M)
+// -------------------------------------
+//
+//                 Page Size        Object Size      Object Alignment
+//                 --------------------------------------------------
+//  Small          2M               <= 265K          MinObjAlignmentInBytes
+//  Medium         32M              <= 4M            4K
+//  Large          N x 2M           > 4M             2M
+//
+
 // Page types
 const uint8_t     ZPageTypeSmall                = 0;
 const uint8_t     ZPageTypeMedium               = 1;
@@ -113,6 +130,7 @@
 
 // Cache line size
 const size_t      ZCacheLineSize                = ZPlatformCacheLineSize;
+#define           ZCACHE_ALIGNED                ATTRIBUTE_ALIGNED(ZCacheLineSize)
 
 // Mark stack space
 extern uintptr_t  ZMarkStackSpaceStart;
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/z/zGranuleMap.hpp
--- a/src/hotspot/share/gc/z/zGranuleMap.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/z/zGranuleMap.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -38,15 +38,15 @@
   const size_t _size;
   T* const     _map;
 
-  size_t index_for_addr(uintptr_t addr) const;
+  size_t index_for_offset(uintptr_t offset) const;
 
 public:
-  ZGranuleMap();
+  ZGranuleMap(size_t max_offset);
   ~ZGranuleMap();
 
-  T get(uintptr_t addr) const;
-  void put(uintptr_t addr, T value);
-  void put(uintptr_t addr, size_t size, T value);
+  T get(uintptr_t offset) const;
+  void put(uintptr_t offset, T value);
+  void put(uintptr_t offset, size_t size, T value);
 };
 
 template <typename T>
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/z/zGranuleMap.inline.hpp
--- a/src/hotspot/share/gc/z/zGranuleMap.inline.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/z/zGranuleMap.inline.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -24,15 +24,18 @@
 #ifndef SHARE_GC_Z_ZGRANULEMAP_INLINE_HPP
 #define SHARE_GC_Z_ZGRANULEMAP_INLINE_HPP
 
-#include "gc/z/zAddress.inline.hpp"
 #include "gc/z/zGlobals.hpp"
 #include "gc/z/zGranuleMap.hpp"
 #include "memory/allocation.inline.hpp"
+#include "utilities/align.hpp"
+#include "utilities/debug.hpp"
 
 template <typename T>
-inline ZGranuleMap<T>::ZGranuleMap() :
-    _size(ZAddressOffsetMax >> ZGranuleSizeShift),
-    _map(MmapArrayAllocator<T>::allocate(_size, mtGC)) {}
+inline ZGranuleMap<T>::ZGranuleMap(size_t max_offset) :
+    _size(max_offset >> ZGranuleSizeShift),
+    _map(MmapArrayAllocator<T>::allocate(_size, mtGC)) {
+  assert(is_aligned(max_offset, ZGranuleSize), "Misaligned");
+}
 
 template <typename T>
 inline ZGranuleMap<T>::~ZGranuleMap() {
@@ -40,32 +43,30 @@
 }
 
 template <typename T>
-inline size_t ZGranuleMap<T>::index_for_addr(uintptr_t addr) const {
-  assert(!ZAddress::is_null(addr), "Invalid address");
-
-  const size_t index = ZAddress::offset(addr) >> ZGranuleSizeShift;
+inline size_t ZGranuleMap<T>::index_for_offset(uintptr_t offset) const {
+  const size_t index = offset >> ZGranuleSizeShift;
   assert(index < _size, "Invalid index");
 
   return index;
 }
 
 template <typename T>
-inline T ZGranuleMap<T>::get(uintptr_t addr) const {
-  const size_t index = index_for_addr(addr);
+inline T ZGranuleMap<T>::get(uintptr_t offset) const {
+  const size_t index = index_for_offset(offset);
   return _map[index];
 }
 
 template <typename T>
-inline void ZGranuleMap<T>::put(uintptr_t addr, T value) {
-  const size_t index = index_for_addr(addr);
+inline void ZGranuleMap<T>::put(uintptr_t offset, T value) {
+  const size_t index = index_for_offset(offset);
   _map[index] = value;
 }
 
 template <typename T>
-inline void ZGranuleMap<T>::put(uintptr_t addr, size_t size, T value) {
+inline void ZGranuleMap<T>::put(uintptr_t offset, size_t size, T value) {
   assert(is_aligned(size, ZGranuleSize), "Misaligned");
 
-  const size_t start_index = index_for_addr(addr);
+  const size_t start_index = index_for_offset(offset);
   const size_t end_index = start_index + (size >> ZGranuleSizeShift);
   for (size_t index = start_index; index < end_index; index++) {
     _map[index] = value;
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/z/zHeap.cpp
--- a/src/hotspot/share/gc/z/zHeap.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/z/zHeap.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -244,34 +244,14 @@
   return _page_allocator.uncommit(delay);
 }
 
-void ZHeap::before_flip() {
-  if (ZVerifyViews) {
-    // Unmap all pages
-    _page_allocator.debug_unmap_all_pages();
-  }
-}
-
-void ZHeap::after_flip() {
-  if (ZVerifyViews) {
-    // Map all pages
-    ZPageTableIterator iter(&_page_table);
-    for (ZPage* page; iter.next(&page);) {
-      _page_allocator.debug_map_page(page);
-    }
-    _page_allocator.debug_map_cached_pages();
-  }
-}
-
 void ZHeap::flip_to_marked() {
-  before_flip();
+  ZVerifyViewsFlip flip(&_page_allocator);
   ZAddress::flip_to_marked();
-  after_flip();
 }
 
 void ZHeap::flip_to_remapped() {
-  before_flip();
+  ZVerifyViewsFlip flip(&_page_allocator);
   ZAddress::flip_to_remapped();
-  after_flip();
 }
 
 void ZHeap::mark_start() {
@@ -460,6 +440,14 @@
   iter.objects_do(cl, visit_weaks);
 }
 
+void ZHeap::pages_do(ZPageClosure* cl) {
+  ZPageTableIterator iter(&_page_table);
+  for (ZPage* page; iter.next(&page);) {
+    cl->do_page(page);
+  }
+  _page_allocator.pages_do(cl);
+}
+
 void ZHeap::serviceability_initialize() {
   _serviceability.initialize();
 }
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/z/zHeap.hpp
--- a/src/hotspot/share/gc/z/zHeap.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/z/zHeap.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -63,9 +63,6 @@
   size_t heap_max_size() const;
   size_t heap_max_reserve_size() const;
 
-  void before_flip();
-  void after_flip();
-
   void flip_to_marked();
   void flip_to_remapped();
 
@@ -151,6 +148,7 @@
 
   // Iteration
   void object_iterate(ObjectClosure* cl, bool visit_weaks);
+  void pages_do(ZPageClosure* cl);
 
   // Serviceability
   void serviceability_initialize();
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/z/zHeapIterator.cpp
--- a/src/hotspot/share/gc/z/zHeapIterator.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/z/zHeapIterator.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -24,6 +24,7 @@
 #include "precompiled.hpp"
 #include "classfile/classLoaderData.hpp"
 #include "classfile/classLoaderDataGraph.hpp"
+#include "gc/z/zAddress.inline.hpp"
 #include "gc/z/zBarrier.inline.hpp"
 #include "gc/z/zGlobals.hpp"
 #include "gc/z/zGranuleMap.inline.hpp"
@@ -126,7 +127,7 @@
 
 ZHeapIterator::ZHeapIterator() :
     _visit_stack(),
-    _visit_map() {}
+    _visit_map(ZAddressOffsetMax) {}
 
 ZHeapIterator::~ZHeapIterator() {
   ZVisitMapIterator iter(&_visit_map);
@@ -148,11 +149,11 @@
 }
 
 ZHeapIteratorBitMap* ZHeapIterator::object_map(oop obj) {
-  const uintptr_t addr = ZOop::to_address(obj);
-  ZHeapIteratorBitMap* map = _visit_map.get(addr);
+  const uintptr_t offset = ZAddress::offset(ZOop::to_address(obj));
+  ZHeapIteratorBitMap* map = _visit_map.get(offset);
   if (map == NULL) {
     map = new ZHeapIteratorBitMap(object_index_max());
-    _visit_map.put(addr, map);
+    _visit_map.put(offset, map);
   }
 
   return map;
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/z/zInitialize.cpp
--- a/src/hotspot/share/gc/z/zInitialize.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/z/zInitialize.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -50,4 +50,6 @@
   ZTracer::initialize();
   ZLargePages::initialize();
   ZBarrierSet::set_barrier_set(barrier_set);
+
+  initialize_os();
 }
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/z/zInitialize.hpp
--- a/src/hotspot/share/gc/z/zInitialize.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/z/zInitialize.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -29,6 +29,9 @@
 class ZBarrierSet;
 
 class ZInitialize {
+private:
+  void initialize_os();
+
 public:
   ZInitialize(ZBarrierSet* barrier_set);
 };
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/z/zMarkStack.hpp
--- a/src/hotspot/share/gc/z/zMarkStack.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/z/zMarkStack.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -73,8 +73,8 @@
 
 class ZMarkStripe {
 private:
-  ZMarkStackList _published  ATTRIBUTE_ALIGNED(ZCacheLineSize);
-  ZMarkStackList _overflowed ATTRIBUTE_ALIGNED(ZCacheLineSize);
+  ZCACHE_ALIGNED ZMarkStackList _published;
+  ZCACHE_ALIGNED ZMarkStackList _overflowed;
 
 public:
   ZMarkStripe();
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/z/zMarkStackAllocator.hpp
--- a/src/hotspot/share/gc/z/zMarkStackAllocator.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/z/zMarkStackAllocator.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -50,8 +50,8 @@
 
 class ZMarkStackAllocator {
 private:
-  ZMarkStackMagazineList _freelist ATTRIBUTE_ALIGNED(ZCacheLineSize);
-  ZMarkStackSpace        _space    ATTRIBUTE_ALIGNED(ZCacheLineSize);
+  ZCACHE_ALIGNED ZMarkStackMagazineList _freelist;
+  ZCACHE_ALIGNED ZMarkStackSpace        _space;
 
   void prime_freelist();
   ZMarkStackMagazine* create_magazine_from_space(uintptr_t addr, size_t size);
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/z/zMarkTerminate.hpp
--- a/src/hotspot/share/gc/z/zMarkTerminate.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/z/zMarkTerminate.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -30,9 +30,9 @@
 
 class ZMarkTerminate {
 private:
-  uint          _nworkers;
-  volatile uint _nworking_stage0 ATTRIBUTE_ALIGNED(ZCacheLineSize);
-  volatile uint _nworking_stage1;
+  uint                         _nworkers;
+  ZCACHE_ALIGNED volatile uint _nworking_stage0;
+  volatile uint                _nworking_stage1;
 
   bool enter_stage(volatile uint* nworking_stage);
   void exit_stage(volatile uint* nworking_stage);
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/z/zMemory.cpp
--- a/src/hotspot/share/gc/z/zMemory.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/z/zMemory.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -26,6 +26,65 @@
 #include "gc/z/zMemory.inline.hpp"
 #include "memory/allocation.inline.hpp"
 
+ZMemory* ZMemoryManager::create(uintptr_t start, size_t size) {
+  ZMemory* const area = new ZMemory(start, size);
+  if (_callbacks._create != NULL) {
+    _callbacks._create(area);
+  }
+  return area;
+}
+
+void ZMemoryManager::destroy(ZMemory* area) {
+  if (_callbacks._destroy != NULL) {
+    _callbacks._destroy(area);
+  }
+  delete area;
+}
+
+void ZMemoryManager::shrink_from_front(ZMemory* area, size_t size) {
+  if (_callbacks._shrink_from_front != NULL) {
+    _callbacks._shrink_from_front(area, size);
+  }
+  area->shrink_from_front(size);
+}
+
+void ZMemoryManager::shrink_from_back(ZMemory* area, size_t size) {
+  if (_callbacks._shrink_from_back != NULL) {
+    _callbacks._shrink_from_back(area, size);
+  }
+  area->shrink_from_back(size);
+}
+
+void ZMemoryManager::grow_from_front(ZMemory* area, size_t size) {
+  if (_callbacks._grow_from_front != NULL) {
+    _callbacks._grow_from_front(area, size);
+  }
+  area->grow_from_front(size);
+}
+
+void ZMemoryManager::grow_from_back(ZMemory* area, size_t size) {
+  if (_callbacks._grow_from_back != NULL) {
+    _callbacks._grow_from_back(area, size);
+  }
+  area->grow_from_back(size);
+}
+
+ZMemoryManager::Callbacks::Callbacks() :
+    _create(NULL),
+    _destroy(NULL),
+    _shrink_from_front(NULL),
+    _shrink_from_back(NULL),
+    _grow_from_front(NULL),
+    _grow_from_back(NULL) {}
+
+ZMemoryManager::ZMemoryManager() :
+    _freelist(),
+    _callbacks() {}
+
+void ZMemoryManager::register_callbacks(const Callbacks& callbacks) {
+  _callbacks = callbacks;
+}
+
 uintptr_t ZMemoryManager::alloc_from_front(size_t size) {
   ZListIterator<ZMemory> iter(&_freelist);
   for (ZMemory* area; iter.next(&area);) {
@@ -34,12 +93,12 @@
         // Exact match, remove area
         const uintptr_t start = area->start();
         _freelist.remove(area);
-        delete area;
+        destroy(area);
         return start;
       } else {
         // Larger than requested, shrink area
         const uintptr_t start = area->start();
-        area->shrink_from_front(size);
+        shrink_from_front(area, size);
         return start;
       }
     }
@@ -57,12 +116,12 @@
       const uintptr_t start = area->start();
       *allocated = area->size();
       _freelist.remove(area);
-      delete area;
+      destroy(area);
       return start;
     } else {
       // Larger than requested, shrink area
       const uintptr_t start = area->start();
-      area->shrink_from_front(size);
+      shrink_from_front(area, size);
       *allocated = size;
       return start;
     }
@@ -81,11 +140,11 @@
         // Exact match, remove area
         const uintptr_t start = area->start();
         _freelist.remove(area);
-        delete area;
+        destroy(area);
         return start;
       } else {
         // Larger than requested, shrink area
-        area->shrink_from_back(size);
+        shrink_from_back(area, size);
         return area->end();
       }
     }
@@ -103,11 +162,11 @@
       const uintptr_t start = area->start();
       *allocated = area->size();
       _freelist.remove(area);
-      delete area;
+      destroy(area);
       return start;
     } else {
       // Larger than requested, shrink area
-      area->shrink_from_back(size);
+      shrink_from_back(area, size);
       *allocated = size;
       return area->end();
     }
@@ -129,20 +188,20 @@
       if (prev != NULL && start == prev->end()) {
         if (end == area->start()) {
           // Merge with prev and current area
-          prev->grow_from_back(size + area->size());
+          grow_from_back(prev, size + area->size());
           _freelist.remove(area);
           delete area;
         } else {
           // Merge with prev area
-          prev->grow_from_back(size);
+          grow_from_back(prev, size);
         }
       } else if (end == area->start()) {
         // Merge with current area
-        area->grow_from_front(size);
+        grow_from_front(area, size);
       } else {
         // Insert new area before current area
         assert(end < area->start(), "Areas must not overlap");
-        ZMemory* new_area = new ZMemory(start, size);
+        ZMemory* const new_area = create(start, size);
         _freelist.insert_before(area, new_area);
       }
 
@@ -155,10 +214,10 @@
   ZMemory* const last = _freelist.last();
   if (last != NULL && start == last->end()) {
     // Merge with last area
-    last->grow_from_back(size);
+    grow_from_back(last, size);
   } else {
     // Insert new area last
-    ZMemory* new_area = new ZMemory(start, size);
+    ZMemory* const new_area = create(start, size);
     _freelist.insert_last(new_area);
   }
 }
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/z/zMemory.hpp
--- a/src/hotspot/share/gc/z/zMemory.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/z/zMemory.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -49,14 +49,42 @@
 };
 
 class ZMemoryManager {
+public:
+  typedef void (*CreateDestroyCallback)(const ZMemory* area);
+  typedef void (*ResizeCallback)(const ZMemory* area, size_t size);
+
+  struct Callbacks {
+    CreateDestroyCallback _create;
+    CreateDestroyCallback _destroy;
+    ResizeCallback        _shrink_from_front;
+    ResizeCallback        _shrink_from_back;
+    ResizeCallback        _grow_from_front;
+    ResizeCallback        _grow_from_back;
+
+    Callbacks();
+  };
+
 private:
   ZList<ZMemory> _freelist;
+  Callbacks      _callbacks;
+
+  ZMemory* create(uintptr_t start, size_t size);
+  void destroy(ZMemory* area);
+  void shrink_from_front(ZMemory* area, size_t size);
+  void shrink_from_back(ZMemory* area, size_t size);
+  void grow_from_front(ZMemory* area, size_t size);
+  void grow_from_back(ZMemory* area, size_t size);
 
 public:
+  ZMemoryManager();
+
+  void register_callbacks(const Callbacks& callbacks);
+
   uintptr_t alloc_from_front(size_t size);
   uintptr_t alloc_from_front_at_most(size_t size, size_t* allocated);
   uintptr_t alloc_from_back(size_t size);
   uintptr_t alloc_from_back_at_most(size_t size, size_t* allocated);
+
   void free(uintptr_t start, size_t size);
 };
 
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/z/zNMethodTableIteration.hpp
--- a/src/hotspot/share/gc/z/zNMethodTableIteration.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/z/zNMethodTableIteration.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -31,9 +31,9 @@
 
 class ZNMethodTableIteration {
 private:
-  ZNMethodTableEntry* _table;
-  size_t              _size;
-  volatile size_t     _claimed ATTRIBUTE_ALIGNED(ZCacheLineSize);
+  ZNMethodTableEntry*            _table;
+  size_t                         _size;
+  ZCACHE_ALIGNED volatile size_t _claimed;
 
 public:
   ZNMethodTableIteration();
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/z/zPage.hpp
--- a/src/hotspot/share/gc/z/zPage.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/z/zPage.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -112,4 +112,9 @@
   void print() const;
 };
 
+class ZPageClosure {
+public:
+  virtual void do_page(const ZPage* page) = 0;
+};
+
 #endif // SHARE_GC_Z_ZPAGE_HPP
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/z/zPageAllocator.cpp
--- a/src/hotspot/share/gc/z/zPageAllocator.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/z/zPageAllocator.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -60,7 +60,9 @@
       _type(type),
       _size(size),
       _flags(flags),
-      _total_collections(total_collections) {}
+      _total_collections(total_collections),
+      _node(),
+      _result() {}
 
   uint8_t type() const {
     return _type;
@@ -78,6 +80,10 @@
     return _total_collections;
   }
 
+  ZPage* peek() {
+    return _result.peek();
+  }
+
   ZPage* wait() {
     return _result.get();
   }
@@ -108,6 +114,7 @@
     _allocated(0),
     _reclaimed(0),
     _queue(),
+    _satisfied(),
     _safe_delete(),
     _uncommit(false),
     _initialized(false) {
@@ -289,11 +296,7 @@
 
 void ZPageAllocator::map_page(const ZPage* page) const {
   // Map physical memory
-  if (!page->is_mapped()) {
-    _physical.map(page->physical_memory(), page->start());
-  } else if (ZVerifyViews) {
-    _physical.debug_map(page->physical_memory(), page->start());
-  }
+  _physical.map(page->physical_memory(), page->start());
 }
 
 size_t ZPageAllocator::max_available(bool no_reserve) const {
@@ -433,14 +436,21 @@
     } while (page == gc_marker);
 
     {
-      // Guard deletion of underlying semaphore. This is a workaround for a
-      // bug in sem_post() in glibc < 2.21, where it's not safe to destroy
+      //
+      // We grab the lock here for two different reasons:
+      //
+      // 1) Guard deletion of underlying semaphore. This is a workaround for
+      // a bug in sem_post() in glibc < 2.21, where it's not safe to destroy
       // the semaphore immediately after returning from sem_wait(). The
       // reason is that sem_post() can touch the semaphore after a waiting
       // thread have returned from sem_wait(). To avoid this race we are
       // forcing the waiting thread to acquire/release the lock held by the
       // posting thread. https://sourceware.org/bugzilla/show_bug.cgi?id=12674
+      //
+      // 2) Guard the list of satisfied pages.
+      //
       ZLocker<ZLock> locker(&_lock);
+      _satisfied.remove(&request);
     }
   }
 
@@ -462,7 +472,9 @@
   }
 
   // Map page if needed
-  map_page(page);
+  if (!page->is_mapped()) {
+    map_page(page);
+  }
 
   // Reset page. This updates the page's sequence number and must
   // be done after page allocation, which potentially blocked in
@@ -500,6 +512,7 @@
     // the dequeue operation must happen first, since the request
     // will immediately be deallocated once it has been satisfied.
     _queue.remove(request);
+    _satisfied.insert_first(request);
     request->satisfy(page);
   }
 }
@@ -686,28 +699,21 @@
   _physical.debug_map(page->physical_memory(), page->start());
 }
 
-class ZPageCacheDebugMapClosure : public StackObj {
-private:
-  const ZPageAllocator* const _allocator;
-
-public:
-  ZPageCacheDebugMapClosure(const ZPageAllocator* allocator) :
-      _allocator(allocator) {}
-
-  virtual void do_page(const ZPage* page) {
-    _allocator->debug_map_page(page);
-  }
-};
-
-void ZPageAllocator::debug_map_cached_pages() const {
+void ZPageAllocator::debug_unmap_page(const ZPage* page) const {
   assert(SafepointSynchronize::is_at_safepoint(), "Should be at safepoint");
-  ZPageCacheDebugMapClosure cl(this);
-  _cache.pages_do(&cl);
+  _physical.debug_unmap(page->physical_memory(), page->start());
 }
 
-void ZPageAllocator::debug_unmap_all_pages() const {
-  assert(SafepointSynchronize::is_at_safepoint(), "Should be at safepoint");
-  _physical.debug_unmap(ZPhysicalMemorySegment(0 /* start */, ZAddressOffsetMax), 0 /* offset */);
+void ZPageAllocator::pages_do(ZPageClosure* cl) const {
+  ZListIterator<ZPageAllocRequest> iter(&_satisfied);
+  for (ZPageAllocRequest* request; iter.next(&request);) {
+    const ZPage* const page = request->peek();
+    if (page != NULL) {
+      cl->do_page(page);
+    }
+  }
+
+  _cache.pages_do(cl);
 }
 
 bool ZPageAllocator::is_alloc_stalled() const {
@@ -728,7 +734,8 @@
     }
 
     // Out of memory, fail allocation request
-    _queue.remove_first();
+    _queue.remove(request);
+    _satisfied.insert_first(request);
     request->satisfy(NULL);
   }
 }
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/z/zPageAllocator.hpp
--- a/src/hotspot/share/gc/z/zPageAllocator.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/z/zPageAllocator.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -54,11 +54,12 @@
   size_t                     _allocated;
   ssize_t                    _reclaimed;
   ZList<ZPageAllocRequest>   _queue;
+  ZList<ZPageAllocRequest>   _satisfied;
   mutable ZSafeDelete<ZPage> _safe_delete;
   bool                       _uncommit;
   bool                       _initialized;
 
-  static ZPage* const      gc_marker;
+  static ZPage* const gc_marker;
 
   void prime_cache(size_t size);
 
@@ -117,11 +118,12 @@
   void map_page(const ZPage* page) const;
 
   void debug_map_page(const ZPage* page) const;
-  void debug_map_cached_pages() const;
-  void debug_unmap_all_pages() const;
+  void debug_unmap_page(const ZPage* page) const;
 
   bool is_alloc_stalled() const;
   void check_out_of_memory();
+
+  void pages_do(ZPageClosure* cl) const;
 };
 
 #endif // SHARE_GC_Z_ZPAGEALLOCATOR_HPP
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/z/zPageCache.cpp
--- a/src/hotspot/share/gc/z/zPageCache.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/z/zPageCache.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -240,3 +240,26 @@
   flush_list(cl, &_medium, to);
   flush_per_numa_lists(cl, &_small, to);
 }
+
+void ZPageCache::pages_do(ZPageClosure* cl) const {
+  // Small
+  ZPerNUMAConstIterator<ZList<ZPage> > iter_numa(&_small);
+  for (const ZList<ZPage>* list; iter_numa.next(&list);) {
+    ZListIterator<ZPage> iter_small(list);
+    for (ZPage* page; iter_small.next(&page);) {
+      cl->do_page(page);
+    }
+  }
+
+  // Medium
+  ZListIterator<ZPage> iter_medium(&_medium);
+  for (ZPage* page; iter_medium.next(&page);) {
+    cl->do_page(page);
+  }
+
+  // Large
+  ZListIterator<ZPage> iter_large(&_large);
+  for (ZPage* page; iter_large.next(&page);) {
+    cl->do_page(page);
+  }
+}
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/z/zPageCache.hpp
--- a/src/hotspot/share/gc/z/zPageCache.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/z/zPageCache.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -71,7 +71,7 @@
 
   void flush(ZPageCacheFlushClosure* cl, ZList<ZPage>* to);
 
-  template <typename Closure> void pages_do(Closure* cl) const;
+  void pages_do(ZPageClosure* cl) const;
 };
 
 #endif // SHARE_GC_Z_ZPAGECACHE_HPP
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/z/zPageCache.inline.hpp
--- a/src/hotspot/share/gc/z/zPageCache.inline.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/z/zPageCache.inline.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -32,28 +32,4 @@
   return _available;
 }
 
-template <typename Closure>
-inline void ZPageCache::pages_do(Closure* cl) const {
-  // Small
-  ZPerNUMAConstIterator<ZList<ZPage> > iter_numa(&_small);
-  for (const ZList<ZPage>* list; iter_numa.next(&list);) {
-    ZListIterator<ZPage> iter_small(list);
-    for (ZPage* page; iter_small.next(&page);) {
-      cl->do_page(page);
-    }
-  }
-
-  // Medium
-  ZListIterator<ZPage> iter_medium(&_medium);
-  for (ZPage* page; iter_medium.next(&page);) {
-    cl->do_page(page);
-  }
-
-  // Large
-  ZListIterator<ZPage> iter_large(&_large);
-  for (ZPage* page; iter_large.next(&page);) {
-    cl->do_page(page);
-  }
-}
-
 #endif // SHARE_GC_Z_ZPAGECACHE_INLINE_HPP
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/z/zPageTable.cpp
--- a/src/hotspot/share/gc/z/zPageTable.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/z/zPageTable.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -22,7 +22,7 @@
  */
 
 #include "precompiled.hpp"
-#include "gc/z/zAddress.inline.hpp"
+#include "gc/z/zGlobals.hpp"
 #include "gc/z/zGranuleMap.inline.hpp"
 #include "gc/z/zPage.inline.hpp"
 #include "gc/z/zPageTable.inline.hpp"
@@ -30,24 +30,24 @@
 #include "utilities/debug.hpp"
 
 ZPageTable::ZPageTable() :
-    _map() {}
+    _map(ZAddressOffsetMax) {}
 
 void ZPageTable::insert(ZPage* page) {
-  const uintptr_t addr = ZAddress::good(page->start());
+  const uintptr_t offset = page->start();
   const size_t size = page->size();
 
   // Make sure a newly created page is
   // visible before updating the page table.
   OrderAccess::storestore();
 
-  assert(get(addr) == NULL, "Invalid entry");
-  _map.put(addr, size, page);
+  assert(_map.get(offset) == NULL, "Invalid entry");
+  _map.put(offset, size, page);
 }
 
 void ZPageTable::remove(ZPage* page) {
-  const uintptr_t addr = ZAddress::good(page->start());
+  const uintptr_t offset = page->start();
   const size_t size = page->size();
 
-  assert(get(addr) == page, "Invalid entry");
-  _map.put(addr, size, NULL);
+  assert(_map.get(offset) == page, "Invalid entry");
+  _map.put(offset, size, NULL);
 }
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/z/zPageTable.inline.hpp
--- a/src/hotspot/share/gc/z/zPageTable.inline.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/z/zPageTable.inline.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -29,7 +29,8 @@
 #include "gc/z/zPageTable.hpp"
 
 inline ZPage* ZPageTable::get(uintptr_t addr) const {
-  return _map.get(addr);
+  assert(!ZAddress::is_null(addr), "Invalid address");
+  return _map.get(ZAddress::offset(addr));
 }
 
 inline ZPageTableIterator::ZPageTableIterator(const ZPageTable* page_table) :
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/z/zRootsIterator.cpp
--- a/src/hotspot/share/gc/z/zRootsIterator.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/z/zRootsIterator.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -149,7 +149,7 @@
 
   virtual void do_code_blob(CodeBlob* cb) {
     nmethod* const nm = cb->as_nmethod_or_null();
-    if (nm != NULL && !nm->test_set_oops_do_mark()) {
+    if (nm != NULL && nm->oops_do_try_claim()) {
       CodeBlobToOopClosure::do_code_blob(cb);
       _bs->disarm(nm);
     }
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/z/zVerify.cpp
--- a/src/hotspot/share/gc/z/zVerify.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/z/zVerify.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -26,6 +26,7 @@
 #include "gc/z/zAddress.hpp"
 #include "gc/z/zHeap.inline.hpp"
 #include "gc/z/zOop.hpp"
+#include "gc/z/zPageAllocator.hpp"
 #include "gc/z/zResurrection.hpp"
 #include "gc/z/zRootsIterator.hpp"
 #include "gc/z/zStat.hpp"
@@ -170,3 +171,38 @@
   ZStatTimerDisable disable;
   roots_and_objects(true /* verify_weaks */);
 }
+
+template <bool Map>
+class ZPageDebugMapOrUnmapClosure : public ZPageClosure {
+private:
+  const ZPageAllocator* const _allocator;
+
+public:
+  ZPageDebugMapOrUnmapClosure(const ZPageAllocator* allocator) :
+      _allocator(allocator) {}
+
+  void do_page(const ZPage* page) {
+    if (Map) {
+      _allocator->debug_map_page(page);
+    } else {
+      _allocator->debug_unmap_page(page);
+    }
+  }
+};
+
+ZVerifyViewsFlip::ZVerifyViewsFlip(const ZPageAllocator* allocator) :
+    _allocator(allocator) {
+  if (ZVerifyViews) {
+    // Unmap all pages
+    ZPageDebugMapOrUnmapClosure<false /* Map */> cl(_allocator);
+    ZHeap::heap()->pages_do(&cl);
+  }
+}
+
+ZVerifyViewsFlip::~ZVerifyViewsFlip() {
+  if (ZVerifyViews) {
+    // Map all pages
+    ZPageDebugMapOrUnmapClosure<true /* Map */> cl(_allocator);
+    ZHeap::heap()->pages_do(&cl);
+  }
+}
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/z/zVerify.hpp
--- a/src/hotspot/share/gc/z/zVerify.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/z/zVerify.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -26,6 +26,8 @@
 
 #include "memory/allocation.hpp"
 
+class ZPageAllocator;
+
 class ZVerify : public AllStatic {
 private:
   template <typename RootsIterator> static void roots();
@@ -45,4 +47,13 @@
   static void after_weak_processing();
 };
 
+class ZVerifyViewsFlip {
+private:
+  const ZPageAllocator* const _allocator;
+
+public:
+  ZVerifyViewsFlip(const ZPageAllocator* allocator);
+  ~ZVerifyViewsFlip();
+};
+
 #endif // SHARE_GC_Z_ZVERIFY_HPP
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/z/zVirtualMemory.cpp
--- a/src/hotspot/share/gc/z/zVirtualMemory.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/z/zVirtualMemory.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -22,10 +22,13 @@
  */
 
 #include "precompiled.hpp"
+#include "gc/z/zAddressSpaceLimit.hpp"
 #include "gc/z/zGlobals.hpp"
 #include "gc/z/zVirtualMemory.inline.hpp"
 #include "logging/log.hpp"
 #include "services/memTracker.hpp"
+#include "utilities/debug.hpp"
+#include "utilities/align.hpp"
 
 ZVirtualMemoryManager::ZVirtualMemoryManager(size_t max_capacity) :
     _manager(),
@@ -38,33 +41,105 @@
     return;
   }
 
-  log_info(gc, init)("Address Space: " SIZE_FORMAT "T", ZAddressOffsetMax / K / G);
-
   // Reserve address space
-  if (reserve(0, ZAddressOffsetMax) < max_capacity) {
-    log_error(gc)("Failed to reserve address space for Java heap");
+  if (!reserve(max_capacity)) {
+    log_error(gc)("Failed to reserve enough address space for Java heap");
     return;
   }
 
+  // Initialize OS specific parts
+  initialize_os();
+
   // Successfully initialized
   _initialized = true;
 }
 
-size_t ZVirtualMemoryManager::reserve(uintptr_t start, size_t size) {
-  if (size < ZGranuleSize) {
+size_t ZVirtualMemoryManager::reserve_discontiguous(uintptr_t start, size_t size, size_t min_range) {
+  if (size < min_range) {
+    // Too small
+    return 0;
+  }
+
+  assert(is_aligned(size, ZGranuleSize), "Misaligned");
+
+  if (reserve_contiguous_platform(start, size)) {
+    // Make the address range free
+    _manager.free(start, size);
+    return size;
+  }
+
+  const size_t half = size / 2;
+  if (half < min_range) {
     // Too small
     return 0;
   }
 
-  if (!reserve_platform(start, size)) {
-    const size_t half = size / 2;
-    return reserve(start, half) + reserve(start + half, half);
+  // Divide and conquer
+  const size_t first_part = align_down(half, ZGranuleSize);
+  const size_t second_part = size - first_part;
+  return reserve_discontiguous(start, first_part, min_range) +
+         reserve_discontiguous(start + first_part, second_part, min_range);
+}
+
+size_t ZVirtualMemoryManager::reserve_discontiguous(size_t size) {
+  // Don't try to reserve address ranges smaller than 1% of the requested size.
+  // This avoids an explosion of reservation attempts in case large parts of the
+  // address space is already occupied.
+  const size_t min_range = align_up(size / 100, ZGranuleSize);
+  size_t start = 0;
+  size_t reserved = 0;
+
+  // Reserve size somewhere between [0, ZAddressOffsetMax)
+  while (reserved < size && start < ZAddressOffsetMax) {
+    const size_t remaining = MIN2(size - reserved, ZAddressOffsetMax - start);
+    reserved += reserve_discontiguous(start, remaining, min_range);
+    start += remaining;
   }
 
-  // Make the address range free
-  _manager.free(start, size);
+  return reserved;
+}
+
+bool ZVirtualMemoryManager::reserve_contiguous(size_t size) {
+  // Allow at most 8192 attempts spread evenly across [0, ZAddressOffsetMax)
+  const size_t end = ZAddressOffsetMax - size;
+  const size_t increment = align_up(end / 8192, ZGranuleSize);
+
+  for (size_t start = 0; start <= end; start += increment) {
+    if (reserve_contiguous_platform(start, size)) {
+      // Make the address range free
+      _manager.free(start, size);
+
+      // Success
+      return true;
+    }
+  }
+
+  // Failed
+  return false;
+}
 
-  return size;
+bool ZVirtualMemoryManager::reserve(size_t max_capacity) {
+  const size_t limit = MIN2(ZAddressOffsetMax, ZAddressSpaceLimit::heap_view());
+  const size_t size = MIN2(max_capacity * ZVirtualToPhysicalRatio, limit);
+
+  size_t reserved = size;
+  bool contiguous = true;
+
+  // Prefer a contiguous address space
+  if (!reserve_contiguous(size)) {
+    // Fall back to a discontiguous address space
+    reserved = reserve_discontiguous(size);
+    contiguous = false;
+  }
+
+  log_info(gc, init)("Address Space Type: %s/%s/%s",
+                     (contiguous ? "Contiguous" : "Discontiguous"),
+                     (limit == ZAddressOffsetMax ? "Unrestricted" : "Restricted"),
+                     (reserved == size ? "Complete" : "Degraded"));
+  log_info(gc, init)("Address Space Size: " SIZE_FORMAT "M x " SIZE_FORMAT " = " SIZE_FORMAT "M",
+                     reserved / M, ZHeapViews, (reserved * ZHeapViews) / M);
+
+  return reserved >= max_capacity;
 }
 
 void ZVirtualMemoryManager::nmt_reserve(uintptr_t start, size_t size) {
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/gc/z/zVirtualMemory.hpp
--- a/src/hotspot/share/gc/z/zVirtualMemory.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/gc/z/zVirtualMemory.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -50,8 +50,14 @@
   ZMemoryManager _manager;
   bool           _initialized;
 
-  bool reserve_platform(uintptr_t start, size_t size);
-  size_t reserve(uintptr_t start, size_t size);
+  void initialize_os();
+
+  bool reserve_contiguous_platform(uintptr_t start, size_t size);
+  bool reserve_contiguous(size_t size);
+  size_t reserve_discontiguous(uintptr_t start, size_t size, size_t min_range);
+  size_t reserve_discontiguous(size_t size);
+  bool reserve(size_t max_capacity);
+
   void nmt_reserve(uintptr_t start, size_t size);
 
 public:
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/jfr/recorder/checkpoint/jfrCheckpointManager.cpp
--- a/src/hotspot/share/jfr/recorder/checkpoint/jfrCheckpointManager.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/jfr/recorder/checkpoint/jfrCheckpointManager.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -24,15 +24,18 @@
 
 #include "precompiled.hpp"
 #include "classfile/javaClasses.inline.hpp"
-#include "jfr/recorder/jfrRecorder.hpp"
+#include "jfr/leakprofiler/checkpoint/objectSampleCheckpoint.hpp"
+#include "jfr/leakprofiler/leakProfiler.hpp"
 #include "jfr/recorder/checkpoint/jfrCheckpointManager.hpp"
 #include "jfr/recorder/checkpoint/jfrCheckpointWriter.hpp"
 #include "jfr/recorder/checkpoint/types/jfrTypeManager.hpp"
+#include "jfr/recorder/checkpoint/types/jfrTypeSet.hpp"
 #include "jfr/recorder/checkpoint/types/traceid/jfrTraceIdEpoch.hpp"
+#include "jfr/recorder/jfrRecorder.hpp"
+#include "jfr/recorder/repository/jfrChunkWriter.hpp"
 #include "jfr/recorder/service/jfrOptionSet.hpp"
 #include "jfr/recorder/storage/jfrMemorySpace.inline.hpp"
 #include "jfr/recorder/storage/jfrStorageUtils.inline.hpp"
-#include "jfr/recorder/repository/jfrChunkWriter.hpp"
 #include "jfr/utilities/jfrBigEndian.hpp"
 #include "jfr/utilities/jfrTypes.hpp"
 #include "logging/log.hpp"
@@ -81,7 +84,7 @@
   if (_lock != NULL) {
     delete _lock;
   }
-  JfrTypeManager::clear();
+  JfrTypeManager::destroy();
 }
 
 static const size_t unlimited_mspace_size = 0;
@@ -332,6 +335,7 @@
 
 typedef DiscardOp<DefaultDiscarder<JfrBuffer> > DiscardOperation;
 size_t JfrCheckpointManager::clear() {
+  JfrTypeSet::clear();
   DiscardOperation discarder(mutexed); // mutexed discard mode
   process_free_list(discarder, _free_list_mspace);
   process_free_list(discarder, _epoch_transition_mspace);
@@ -353,12 +357,34 @@
 }
 
 void JfrCheckpointManager::write_type_set() {
-  JfrTypeManager::write_type_set();
+  assert(!SafepointSynchronize::is_at_safepoint(), "invariant");
+  // can safepoint here
+  MutexLocker cld_lock(ClassLoaderDataGraph_lock);
+  MutexLocker module_lock(Module_lock);
+  if (!LeakProfiler::is_running()) {
+    JfrCheckpointWriter writer(true, true, Thread::current());
+    JfrTypeSet::serialize(&writer, NULL, false);
+    return;
+  }
+  Thread* const t = Thread::current();
+  JfrCheckpointWriter leakp_writer(false, true, t);
+  JfrCheckpointWriter writer(false, true, t);
+  JfrTypeSet::serialize(&writer, &leakp_writer, false);
+  ObjectSampleCheckpoint::on_type_set(leakp_writer);
 }
 
 void JfrCheckpointManager::write_type_set_for_unloaded_classes() {
   assert_locked_or_safepoint(ClassLoaderDataGraph_lock);
-  JfrTypeManager::write_type_set_for_unloaded_classes();
+  JfrCheckpointWriter writer(false, true, Thread::current());
+  const JfrCheckpointContext ctx = writer.context();
+  JfrTypeSet::serialize(&writer, NULL, true);
+  if (LeakProfiler::is_running()) {
+    ObjectSampleCheckpoint::on_type_set_unload(writer);
+  }
+  if (!JfrRecorder::is_recording()) {
+    // discard by rewind
+    writer.set_context(ctx);
+  }
 }
 
 void JfrCheckpointManager::create_thread_blob(JavaThread* jt) {
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/jfr/recorder/checkpoint/types/jfrType.cpp
--- a/src/hotspot/share/jfr/recorder/checkpoint/types/jfrType.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/jfr/recorder/checkpoint/types/jfrType.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -36,7 +36,6 @@
 #include "jfr/recorder/jfrRecorder.hpp"
 #include "jfr/recorder/checkpoint/types/jfrThreadGroup.hpp"
 #include "jfr/recorder/checkpoint/types/jfrThreadState.hpp"
-#include "jfr/recorder/checkpoint/types/jfrTypeSet.hpp"
 #include "jfr/support/jfrThreadLocal.hpp"
 #include "jfr/writers/jfrJavaEventWriter.hpp"
 #include "memory/metaspaceGCThresholdUpdater.hpp"
@@ -271,30 +270,6 @@
   }
 }
 
-class TypeSetSerialization {
- private:
-  JfrCheckpointWriter* _leakp_writer;
-  bool _class_unload;
- public:
-  TypeSetSerialization(bool class_unload, JfrCheckpointWriter* leakp_writer = NULL) :
-    _leakp_writer(leakp_writer), _class_unload(class_unload) {}
-  void write(JfrCheckpointWriter& writer) {
-    JfrTypeSet::serialize(&writer, _leakp_writer, _class_unload);
-  }
-};
-
-void ClassUnloadTypeSet::serialize(JfrCheckpointWriter& writer) {
-  TypeSetSerialization type_set(true);
-  type_set.write(writer);
-};
-
-TypeSet::TypeSet(JfrCheckpointWriter* leakp_writer) : _leakp_writer(leakp_writer) {}
-
-void TypeSet::serialize(JfrCheckpointWriter& writer) {
-  TypeSetSerialization type_set(false, _leakp_writer);
-  type_set.write(writer);
-};
-
 void ThreadStateConstant::serialize(JfrCheckpointWriter& writer) {
   JfrThreadState::serialize(writer);
 }
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/jfr/recorder/checkpoint/types/jfrType.hpp
--- a/src/hotspot/share/jfr/recorder/checkpoint/types/jfrType.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/jfr/recorder/checkpoint/types/jfrType.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -37,11 +37,6 @@
   void serialize(JfrCheckpointWriter& writer);
 };
 
-class ClassUnloadTypeSet : public JfrSerializer {
- public:
-  void serialize(JfrCheckpointWriter& writer);
-};
-
 class FlagValueOriginConstant : public JfrSerializer {
  public:
   void serialize(JfrCheckpointWriter& writer);
@@ -107,14 +102,6 @@
   void serialize(JfrCheckpointWriter& writer);
 };
 
-class TypeSet : public JfrSerializer {
- private:
-  JfrCheckpointWriter* _leakp_writer;
- public:
-  explicit TypeSet(JfrCheckpointWriter* leakp_writer = NULL);
-  void serialize(JfrCheckpointWriter& writer);
-};
-
 class ThreadStateConstant : public JfrSerializer {
  public:
   void serialize(JfrCheckpointWriter& writer);
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/jfr/recorder/checkpoint/types/jfrTypeManager.cpp
--- a/src/hotspot/share/jfr/recorder/checkpoint/types/jfrTypeManager.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/jfr/recorder/checkpoint/types/jfrTypeManager.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -23,9 +23,6 @@
  */
 
 #include "precompiled.hpp"
-#include "jfr/jfr.hpp"
-#include "jfr/leakprofiler/leakProfiler.hpp"
-#include "jfr/leakprofiler/checkpoint/objectSampleCheckpoint.hpp"
 #include "jfr/metadata/jfrSerializer.hpp"
 #include "jfr/recorder/checkpoint/jfrCheckpointWriter.hpp"
 #include "jfr/recorder/checkpoint/types/jfrType.hpp"
@@ -35,9 +32,9 @@
 #include "memory/resourceArea.hpp"
 #include "runtime/handles.inline.hpp"
 #include "runtime/safepoint.hpp"
+#include "runtime/semaphore.hpp"
 #include "runtime/thread.inline.hpp"
 #include "utilities/exceptions.hpp"
-#include "runtime/semaphore.hpp"
 
 class JfrSerializerRegistration : public JfrCHeapObj {
  private:
@@ -120,7 +117,7 @@
 static List types;
 static List safepoint_types;
 
-void JfrTypeManager::clear() {
+void JfrTypeManager::destroy() {
   SerializerRegistrationGuard guard;
   Iterator iter(types);
   JfrSerializerRegistration* registration;
@@ -152,39 +149,6 @@
   }
 }
 
-void JfrTypeManager::write_type_set() {
-  assert(!SafepointSynchronize::is_at_safepoint(), "invariant");
-  // can safepoint here
-  MutexLocker cld_lock(ClassLoaderDataGraph_lock);
-  MutexLocker module_lock(Module_lock);
-  if (!LeakProfiler::is_running()) {
-    JfrCheckpointWriter writer(true, true, Thread::current());
-    TypeSet set;
-    set.serialize(writer);
-    return;
-  }
-  JfrCheckpointWriter leakp_writer(false, true, Thread::current());
-  JfrCheckpointWriter writer(false, true, Thread::current());
-  TypeSet set(&leakp_writer);
-  set.serialize(writer);
-  ObjectSampleCheckpoint::on_type_set(leakp_writer);
-}
-
-void JfrTypeManager::write_type_set_for_unloaded_classes() {
-  assert_locked_or_safepoint(ClassLoaderDataGraph_lock);
-  JfrCheckpointWriter writer(false, true, Thread::current());
-  const JfrCheckpointContext ctx = writer.context();
-  ClassUnloadTypeSet class_unload_set;
-  class_unload_set.serialize(writer);
-  if (LeakProfiler::is_running()) {
-    ObjectSampleCheckpoint::on_type_set_unload(writer);
-  }
-  if (!Jfr::is_recording()) {
-    // discard anything written
-    writer.set_context(ctx);
-  }
-}
-
 void JfrTypeManager::create_thread_blob(JavaThread* jt) {
   assert(jt != NULL, "invariant");
   ResourceMark rm(jt);
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/jfr/recorder/checkpoint/types/jfrTypeManager.hpp
--- a/src/hotspot/share/jfr/recorder/checkpoint/types/jfrTypeManager.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/jfr/recorder/checkpoint/types/jfrTypeManager.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -32,11 +32,9 @@
 class JfrTypeManager : public AllStatic {
  public:
   static bool initialize();
-  static void clear();
+  static void destroy();
   static void write_types(JfrCheckpointWriter& writer);
   static void write_safepoint_types(JfrCheckpointWriter& writer);
-  static void write_type_set();
-  static void write_type_set_for_unloaded_classes();
   static void create_thread_blob(JavaThread* jt);
   static void write_thread_checkpoint(JavaThread* jt);
 };
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/jfr/recorder/checkpoint/types/jfrTypeSet.cpp
--- a/src/hotspot/share/jfr/recorder/checkpoint/types/jfrTypeSet.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/jfr/recorder/checkpoint/types/jfrTypeSet.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -204,9 +204,14 @@
   return write_klass(writer, klass, true);
 }
 
+static bool is_implied(const Klass* klass) {
+  assert(klass != NULL, "invariant");
+  return klass->is_subclass_of(SystemDictionary::ClassLoader_klass()) || klass == SystemDictionary::Object_klass();
+}
+
 static void do_implied(Klass* klass) {
   assert(klass != NULL, "invariant");
-  if (klass->is_subclass_of(SystemDictionary::ClassLoader_klass()) || klass == SystemDictionary::Object_klass()) {
+  if (is_implied(klass)) {
     if (_leakp_writer != NULL) {
       SET_LEAKP(klass);
     }
@@ -259,6 +264,16 @@
 typedef CompositeFunctor<KlassPtr, KlassWriter, KlassArtifactRegistrator> KlassWriterRegistration;
 typedef JfrArtifactCallbackHost<KlassPtr, KlassWriterRegistration> KlassCallback;
 
+template <>
+class LeakPredicate<const Klass*> {
+public:
+  LeakPredicate(bool class_unload) {}
+  bool operator()(const Klass* klass) {
+    assert(klass != NULL, "invariant");
+    return IS_LEAKP(klass) || is_implied(klass);
+  }
+};
+
 typedef LeakPredicate<KlassPtr> LeakKlassPredicate;
 typedef JfrPredicatedTypeWriterImplHost<KlassPtr, LeakKlassPredicate, write__klass__leakp> LeakKlassWriterImpl;
 typedef JfrTypeWriterHost<LeakKlassWriterImpl, TYPE_CLASS> LeakKlassWriter;
@@ -809,6 +824,12 @@
   _artifacts->tally(sw);
 }
 
+static bool clear_artifacts = false;
+
+void JfrTypeSet::clear() {
+  clear_artifacts = true;
+}
+
 typedef Wrapper<KlassPtr, ClearArtifact> ClearKlassBits;
 typedef Wrapper<MethodPtr, ClearArtifact> ClearMethodFlag;
 typedef MethodIteratorHost<ClearMethodFlag, ClearKlassBits, false> ClearKlassAndMethods;
@@ -820,7 +841,7 @@
     assert(_writer != NULL, "invariant");
     ClearKlassAndMethods clear(_writer);
     _artifacts->iterate_klasses(clear);
-    _artifacts->clear();
+    JfrTypeSet::clear();
     ++checkpoint_id;
   }
   return total_count;
@@ -833,8 +854,9 @@
   if (_artifacts == NULL) {
     _artifacts = new JfrArtifactSet(class_unload);
   } else {
-    _artifacts->initialize(class_unload);
+    _artifacts->initialize(class_unload, clear_artifacts);
   }
+  clear_artifacts = false;
   assert(_artifacts != NULL, "invariant");
   assert(!_artifacts->has_klass_entries(), "invariant");
 }
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/jfr/recorder/checkpoint/types/jfrTypeSet.hpp
--- a/src/hotspot/share/jfr/recorder/checkpoint/types/jfrTypeSet.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/jfr/recorder/checkpoint/types/jfrTypeSet.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -31,6 +31,7 @@
 
 class JfrTypeSet : AllStatic {
  public:
+  static void clear();
   static size_t serialize(JfrCheckpointWriter* writer, JfrCheckpointWriter* leakp_writer, bool class_unload);
 };
 
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/jfr/recorder/checkpoint/types/jfrTypeSetUtils.cpp
--- a/src/hotspot/share/jfr/recorder/checkpoint/types/jfrTypeSetUtils.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/jfr/recorder/checkpoint/types/jfrTypeSetUtils.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -35,6 +35,8 @@
   _cstring_table(new CStringTable(this)),
   _sym_list(NULL),
   _cstring_list(NULL),
+  _sym_query(NULL),
+  _cstring_query(NULL),
   _symbol_id_counter(1),
   _class_unload(false) {
   assert(_sym_table != NULL, "invariant");
@@ -66,9 +68,11 @@
   assert(!_cstring_table->has_entries(), "invariant");
 
   _sym_list = NULL;
-  _cstring_list = NULL;
   _symbol_id_counter = 1;
 
+  _sym_query = NULL;
+  _cstring_query = NULL;
+
   assert(bootstrap != NULL, "invariant");
   bootstrap->reset();
   _cstring_list = bootstrap;
@@ -88,10 +92,10 @@
 }
 
 bool JfrSymbolId::on_equals(uintptr_t hash, const SymbolEntry* entry) {
-  // query might be NULL
   assert(entry != NULL, "invariant");
   assert(entry->hash() == hash, "invariant");
-  return true;
+  assert(_sym_query != NULL, "invariant");
+  return _sym_query == entry->literal();
 }
 
 void JfrSymbolId::on_unlink(const SymbolEntry* entry) {
@@ -99,18 +103,36 @@
   const_cast<Symbol*>(entry->literal())->decrement_refcount();
 }
 
+static const char* resource_to_cstring(const char* resource_str) {
+  assert(resource_str != NULL, "invariant");
+  const size_t length = strlen(resource_str);
+  char* const c_string = JfrCHeapObj::new_array<char>(length + 1);
+  assert(c_string != NULL, "invariant");
+  strncpy(c_string, resource_str, length + 1);
+  return c_string;
+}
+
 void JfrSymbolId::on_link(const CStringEntry* entry) {
   assert(entry != NULL, "invariant");
   assert(entry->id() == 0, "invariant");
   entry->set_id(++_symbol_id_counter);
+  const_cast<CStringEntry*>(entry)->set_literal(resource_to_cstring(entry->literal()));
   entry->set_list_next(_cstring_list);
   _cstring_list = entry;
 }
 
+static bool string_compare(const char* query, const char* candidate) {
+  assert(query != NULL, "invariant");
+  assert(candidate != NULL, "invariant");
+  const size_t length = strlen(query);
+  return strncmp(query, candidate, length) == 0;
+}
+
 bool JfrSymbolId::on_equals(uintptr_t hash, const CStringEntry* entry) {
   assert(entry != NULL, "invariant");
   assert(entry->hash() == hash, "invariant");
-  return true;
+  assert(_cstring_query != NULL, "invariant");
+  return string_compare(_cstring_query, entry->literal());
 }
 
 void JfrSymbolId::on_unlink(const CStringEntry* entry) {
@@ -131,16 +153,10 @@
   return mark((uintptr_t)symbol->identity_hash(), symbol, leakp);
 }
 
-static unsigned int last_symbol_hash = 0;
-static traceid last_symbol_id = 0;
-
 traceid JfrSymbolId::mark(uintptr_t hash, const Symbol* data, bool leakp) {
   assert(data != NULL, "invariant");
   assert(_sym_table != NULL, "invariant");
-  if (hash == last_symbol_hash) {
-    assert(last_symbol_id != 0, "invariant");
-    return last_symbol_id;
-  }
+  _sym_query = data;
   const SymbolEntry& entry = _sym_table->lookup_put(hash, data);
   if (_class_unload) {
     entry.set_unloading();
@@ -148,21 +164,13 @@
   if (leakp) {
     entry.set_leakp();
   }
-  last_symbol_hash = hash;
-  last_symbol_id = entry.id();
-  return last_symbol_id;
+  return entry.id();
 }
 
-static unsigned int last_cstring_hash = 0;
-static traceid last_cstring_id = 0;
-
 traceid JfrSymbolId::mark(uintptr_t hash, const char* str, bool leakp) {
   assert(str != NULL, "invariant");
   assert(_cstring_table != NULL, "invariant");
-  if (hash == last_cstring_hash) {
-    assert(last_cstring_id != 0, "invariant");
-    return last_cstring_id;
-  }
+  _cstring_query = str;
   const CStringEntry& entry = _cstring_table->lookup_put(hash, str);
   if (_class_unload) {
     entry.set_unloading();
@@ -170,9 +178,7 @@
   if (leakp) {
     entry.set_leakp();
   }
-  last_cstring_hash = hash;
-  last_cstring_id = entry.id();
-  return last_cstring_id;
+  return entry.id();
 }
 
 /*
@@ -202,7 +208,7 @@
   sprintf(hash_buf, "/" UINTX_FORMAT, hash);
   const size_t hash_len = strlen(hash_buf);
   const size_t result_len = ik->name()->utf8_length();
-  anonymous_symbol = JfrCHeapObj::new_array<char>(result_len + hash_len + 1);
+  anonymous_symbol = NEW_RESOURCE_ARRAY(char, result_len + hash_len + 1);
   ik->name()->as_klass_external_name(anonymous_symbol, (int)result_len + 1);
   assert(strlen(anonymous_symbol) == result_len, "invariant");
   strcpy(anonymous_symbol + result_len, hash_buf);
@@ -215,21 +221,12 @@
   return k->is_instance_klass() && ((const InstanceKlass*)k)->is_unsafe_anonymous();
 }
 
-static unsigned int last_anonymous_hash = 0;
-static traceid last_anonymous_id = 0;
-
 traceid JfrSymbolId::mark_unsafe_anonymous_klass_name(const InstanceKlass* ik, bool leakp) {
   assert(ik != NULL, "invariant");
   assert(ik->is_unsafe_anonymous(), "invariant");
   const uintptr_t hash = unsafe_anonymous_klass_name_hash(ik);
-  if (hash == last_anonymous_hash) {
-    assert(last_anonymous_id != 0, "invariant");
-    return last_anonymous_id;
-  }
-  last_anonymous_hash = hash;
-  const CStringEntry* const entry = _cstring_table->lookup_only(hash);
-  last_anonymous_id = entry != NULL ? entry->id() : mark(hash, create_unsafe_anonymous_klass_symbol(ik, hash), leakp);
-  return last_anonymous_id;
+  const char* const anonymous_klass_symbol = create_unsafe_anonymous_klass_symbol(ik, hash);
+  return mark(hash, anonymous_klass_symbol, leakp);
 }
 
 traceid JfrSymbolId::mark(const Klass* k, bool leakp) {
@@ -249,23 +246,20 @@
   return symbol_id;
 }
 
-static void reset_symbol_caches() {
-  last_anonymous_hash = 0;
-  last_symbol_hash = 0;
-  last_cstring_hash = 0;
-}
-
 JfrArtifactSet::JfrArtifactSet(bool class_unload) : _symbol_id(new JfrSymbolId()),
-                                                     _klass_list(NULL),
-                                                     _total_count(0) {
+                                                    _klass_list(NULL),
+                                                    _total_count(0) {
   initialize(class_unload);
   assert(_klass_list != NULL, "invariant");
 }
 
 static const size_t initial_class_list_size = 200;
 
-void JfrArtifactSet::initialize(bool class_unload) {
+void JfrArtifactSet::initialize(bool class_unload, bool clear /* false */) {
   assert(_symbol_id != NULL, "invariant");
+  if (clear) {
+    _symbol_id->clear();
+  }
   _symbol_id->set_class_unload(class_unload);
   _total_count = 0;
   // resource allocation
@@ -273,13 +267,8 @@
 }
 
 JfrArtifactSet::~JfrArtifactSet() {
-  clear();
+  _symbol_id->clear();
   delete _symbol_id;
-}
-
-void JfrArtifactSet::clear() {
-  reset_symbol_caches();
-  _symbol_id->clear();
   // _klass_list will be cleared by a ResourceMark
 }
 
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/jfr/recorder/checkpoint/types/jfrTypeSetUtils.hpp
--- a/src/hotspot/share/jfr/recorder/checkpoint/types/jfrTypeSetUtils.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/jfr/recorder/checkpoint/types/jfrTypeSetUtils.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -222,6 +222,8 @@
   CStringTable* _cstring_table;
   const SymbolEntry* _sym_list;
   const CStringEntry* _cstring_list;
+  const Symbol* _sym_query;
+  const char* _cstring_query;
   traceid _symbol_id_counter;
   bool _class_unload;
 
@@ -300,9 +302,7 @@
   ~JfrArtifactSet();
 
   // caller needs ResourceMark
-  void initialize(bool class_unload);
-  void clear();
-
+  void initialize(bool class_unload, bool clear = false);
 
   traceid mark(uintptr_t hash, const Symbol* sym, bool leakp);
   traceid mark(const Klass* klass, bool leakp);
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/jvmci/jvmciCompilerToVM.cpp
--- a/src/hotspot/share/jvmci/jvmciCompilerToVM.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/jvmci/jvmciCompilerToVM.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -2330,6 +2330,16 @@
   return true;
 C2V_END
 
+C2V_VMENTRY_PREFIX(jlong, getCurrentJavaThread, (JNIEnv* env, jobject c2vm))
+  if (base_thread == NULL) {
+    // Called from unattached JVMCI shared library thread
+    return 0L;
+  }
+  JVMCITraceMark jtm("getCurrentJavaThread");
+  assert(base_thread->is_Java_thread(), "just checking");
+  return (jlong) p2i(base_thread);
+C2V_END
+
 C2V_VMENTRY_PREFIX(jboolean, attachCurrentThread, (JNIEnv* env, jobject c2vm, jboolean as_daemon))
   if (base_thread == NULL) {
     // Called from unattached JVMCI shared library thread
@@ -2743,6 +2753,7 @@
   {CC "deleteGlobalHandle",                           CC "(J)V",                                                                            FN_PTR(deleteGlobalHandle)},
   {CC "registerNativeMethods",                        CC "(" CLASS ")[J",                                                                   FN_PTR(registerNativeMethods)},
   {CC "isCurrentThreadAttached",                      CC "()Z",                                                                             FN_PTR(isCurrentThreadAttached)},
+  {CC "getCurrentJavaThread",                         CC "()J",                                                                             FN_PTR(getCurrentJavaThread)},
   {CC "attachCurrentThread",                          CC "(Z)Z",                                                                            FN_PTR(attachCurrentThread)},
   {CC "detachCurrentThread",                          CC "()V",                                                                             FN_PTR(detachCurrentThread)},
   {CC "translate",                                    CC "(" OBJECT ")J",                                                                   FN_PTR(translate)},
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/jvmci/vmStructs_jvmci.cpp
--- a/src/hotspot/share/jvmci/vmStructs_jvmci.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/jvmci/vmStructs_jvmci.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -180,6 +180,7 @@
   nonstatic_field(JavaThread,                  _pending_transfer_to_interpreter,              bool)                                  \
   nonstatic_field(JavaThread,                  _jvmci_counters,                               jlong*)                                \
   nonstatic_field(JavaThread,                  _should_post_on_exceptions_flag,               int)                                   \
+  nonstatic_field(JavaThread,                  _jni_environment,                              JNIEnv)                                \
   nonstatic_field(JavaThread,                  _reserved_stack_activation,                    address)                               \
                                                                                                                                      \
   static_field(java_lang_Class,                _klass_offset,                                 int)                                   \
@@ -538,6 +539,7 @@
   declare_constant(FieldInfo::field_slots)                                \
                                                                           \
   declare_constant(InstanceKlass::linked)                                 \
+  declare_constant(InstanceKlass::being_initialized)                      \
   declare_constant(InstanceKlass::fully_initialized)                      \
   declare_constant(InstanceKlass::_misc_is_unsafe_anonymous)              \
                                                                           \
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/memory/iterator.cpp
--- a/src/hotspot/share/memory/iterator.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/memory/iterator.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -59,7 +59,7 @@
 
 void MarkingCodeBlobClosure::do_code_blob(CodeBlob* cb) {
   nmethod* nm = cb->as_nmethod_or_null();
-  if (nm != NULL && !nm->test_set_oops_do_mark()) {
+  if (nm != NULL && nm->oops_do_try_claim()) {
     do_nmethod(nm);
   }
 }
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/oops/instanceKlass.cpp
--- a/src/hotspot/share/oops/instanceKlass.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/oops/instanceKlass.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -69,6 +69,7 @@
 #include "prims/jvmtiThreadState.hpp"
 #include "prims/methodComparator.hpp"
 #include "runtime/atomic.hpp"
+#include "runtime/biasedLocking.hpp"
 #include "runtime/fieldDescriptor.inline.hpp"
 #include "runtime/handles.inline.hpp"
 #include "runtime/javaCalls.hpp"
@@ -456,6 +457,12 @@
   if (Arguments::is_dumping_archive()) {
     SystemDictionaryShared::init_dumptime_info(this);
   }
+
+  // Set biased locking bit for all instances of this class; it will be
+  // cleared if revocation occurs too often for this type
+  if (UseBiasedLocking && BiasedLocking::enabled()) {
+    set_prototype_header(markWord::biased_locking_prototype());
+  }
 }
 
 void InstanceKlass::deallocate_methods(ClassLoaderData* loader_data,
@@ -2408,6 +2415,11 @@
     // --> see ArrayKlass::complete_create_array_klass()
     array_klasses()->restore_unshareable_info(ClassLoaderData::the_null_class_loader_data(), Handle(), CHECK);
   }
+
+  // Initialize current biased locking state.
+  if (UseBiasedLocking && BiasedLocking::enabled()) {
+    set_prototype_header(markWord::biased_locking_prototype());
+  }
 }
 
 // returns true IFF is_in_error_state() has been changed as a result of this call.
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/oops/method.cpp
--- a/src/hotspot/share/oops/method.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/oops/method.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -25,6 +25,7 @@
 #include "precompiled.hpp"
 #include "classfile/classLoaderDataGraph.hpp"
 #include "classfile/metadataOnStackMark.hpp"
+#include "classfile/symbolTable.hpp"
 #include "classfile/systemDictionary.hpp"
 #include "code/codeCache.hpp"
 #include "code/debugInfoRec.hpp"
@@ -378,7 +379,83 @@
   assert(valid_itable_index(), "");
 }
 
+// The RegisterNatives call being attempted tried to register with a method that
+// is not native.  Ask JVM TI what prefixes have been specified.  Then check
+// to see if the native method is now wrapped with the prefixes.  See the
+// SetNativeMethodPrefix(es) functions in the JVM TI Spec for details.
+static Method* find_prefixed_native(Klass* k, Symbol* name, Symbol* signature, TRAPS) {
+#if INCLUDE_JVMTI
+  ResourceMark rm(THREAD);
+  Method* method;
+  int name_len = name->utf8_length();
+  char* name_str = name->as_utf8();
+  int prefix_count;
+  char** prefixes = JvmtiExport::get_all_native_method_prefixes(&prefix_count);
+  for (int i = 0; i < prefix_count; i++) {
+    char* prefix = prefixes[i];
+    int prefix_len = (int)strlen(prefix);
 
+    // try adding this prefix to the method name and see if it matches another method name
+    int trial_len = name_len + prefix_len;
+    char* trial_name_str = NEW_RESOURCE_ARRAY(char, trial_len + 1);
+    strcpy(trial_name_str, prefix);
+    strcat(trial_name_str, name_str);
+    TempNewSymbol trial_name = SymbolTable::probe(trial_name_str, trial_len);
+    if (trial_name == NULL) {
+      continue; // no such symbol, so this prefix wasn't used, try the next prefix
+    }
+    method = k->lookup_method(trial_name, signature);
+    if (method == NULL) {
+      continue; // signature doesn't match, try the next prefix
+    }
+    if (method->is_native()) {
+      method->set_is_prefixed_native();
+      return method; // wahoo, we found a prefixed version of the method, return it
+    }
+    // found as non-native, so prefix is good, add it, probably just need more prefixes
+    name_len = trial_len;
+    name_str = trial_name_str;
+  }
+#endif // INCLUDE_JVMTI
+  return NULL; // not found
+}
+
+bool Method::register_native(Klass* k, Symbol* name, Symbol* signature, address entry, TRAPS) {
+  Method* method = k->lookup_method(name, signature);
+  if (method == NULL) {
+    ResourceMark rm(THREAD);
+    stringStream st;
+    st.print("Method '");
+    print_external_name(&st, k, name, signature);
+    st.print("' name or signature does not match");
+    THROW_MSG_(vmSymbols::java_lang_NoSuchMethodError(), st.as_string(), false);
+  }
+  if (!method->is_native()) {
+    // trying to register to a non-native method, see if a JVM TI agent has added prefix(es)
+    method = find_prefixed_native(k, name, signature, THREAD);
+    if (method == NULL) {
+      ResourceMark rm(THREAD);
+      stringStream st;
+      st.print("Method '");
+      print_external_name(&st, k, name, signature);
+      st.print("' is not declared as native");
+      THROW_MSG_(vmSymbols::java_lang_NoSuchMethodError(), st.as_string(), false);
+    }
+  }
+
+  if (entry != NULL) {
+    method->set_native_function(entry, native_bind_event_is_interesting);
+  } else {
+    method->clear_native_function();
+  }
+  if (PrintJNIResolving) {
+    ResourceMark rm(THREAD);
+    tty->print_cr("[Registering JNI native method %s.%s]",
+      method->method_holder()->external_name(),
+      method->name()->as_C_string());
+  }
+  return true;
+}
 
 bool Method::was_executed_more_than(int n) {
   // Invocation counter is reset when the Method* is compiled.
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/oops/method.hpp
--- a/src/hotspot/share/oops/method.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/oops/method.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -346,6 +346,12 @@
   // InterpreterRuntime::exception_handler_for_exception.
   static int fast_exception_handler_bci_for(const methodHandle& mh, Klass* ex_klass, int throw_bci, TRAPS);
 
+  static bool register_native(Klass* k,
+                              Symbol* name,
+                              Symbol* signature,
+                              address entry,
+                              TRAPS);
+
   // method data access
   MethodData* method_data() const              {
     return _method_data;
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/oops/oopsHierarchy.cpp
--- a/src/hotspot/share/oops/oopsHierarchy.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/oops/oopsHierarchy.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2005, 2015, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2005, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -37,8 +37,6 @@
   Thread* t = Thread::current_or_null();
   if (t != NULL && t->is_Java_thread()) {
      frame fr = os::current_frame();
-     // This points to the oop creator, I guess current frame points to caller
-     assert (fr.pc(), "should point to a vm frame");
      t->unhandled_oops()->register_unhandled_oop(this, fr.pc());
   }
 }
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/opto/loopnode.hpp
--- a/src/hotspot/share/opto/loopnode.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/opto/loopnode.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -1378,7 +1378,7 @@
   bool exceeding_node_budget(uint required = 0) {
     assert(C->live_nodes() < C->max_node_limit(), "sanity");
     uint available = C->max_node_limit() - C->live_nodes();
-    return available < required + _nodes_required;
+    return available < required + _nodes_required + REQUIRE_MIN;
   }
 
   uint require_nodes(uint require, uint minreq = REQUIRE_MIN) {
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/opto/loopopts.cpp
--- a/src/hotspot/share/opto/loopopts.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/opto/loopopts.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -3159,7 +3159,8 @@
   Node_List worklist(area);
   Node_List sink_list(area);
 
-  if (!may_require_nodes(loop->est_loop_clone_sz(2))) {
+  uint estimate = loop->est_loop_clone_sz(1);
+  if (exceeding_node_budget(estimate)) {
     return false;
   }
 
@@ -3184,8 +3185,7 @@
 
   // Set of non-cfg nodes to peel are those that are control
   // dependent on the cfg nodes.
-  uint i;
-  for(i = 0; i < loop->_body.size(); i++ ) {
+  for (uint i = 0; i < loop->_body.size(); i++) {
     Node *n = loop->_body.at(i);
     Node *n_c = has_ctrl(n) ? get_ctrl(n) : n;
     if (peel.test(n_c->_idx)) {
@@ -3200,7 +3200,7 @@
 
   // Get a post order schedule of nodes in the peel region
   // Result in right-most operand.
-  scheduled_nodelist(loop, peel, peel_list );
+  scheduled_nodelist(loop, peel, peel_list);
 
   assert(is_valid_loop_partition(loop, peel, peel_list, not_peel), "bad partition");
 
@@ -3220,25 +3220,21 @@
   // Evacuate nodes in peel region into the not_peeled region if possible
   uint new_phi_cnt = 0;
   uint cloned_for_outside_use = 0;
-  for (i = 0; i < peel_list.size();) {
+  for (uint i = 0; i < peel_list.size();) {
     Node* n = peel_list.at(i);
 #ifndef PRODUCT
   if (TracePartialPeeling) n->dump();
 #endif
     bool incr = true;
-    if ( !n->is_CFG() ) {
-
-      if ( has_use_in_set(n, not_peel) ) {
-
+    if (!n->is_CFG()) {
+      if (has_use_in_set(n, not_peel)) {
         // If not used internal to the peeled region,
         // move "n" from peeled to not_peeled region.
-
-        if ( !has_use_internal_to_set(n, peel, loop) ) {
-
+        if (!has_use_internal_to_set(n, peel, loop)) {
           // if not pinned and not a load (which maybe anti-dependent on a store)
           // and not a CMove (Matcher expects only bool->cmove).
           if (n->in(0) == NULL && !n->is_Load() && !n->is_CMove()) {
-            cloned_for_outside_use += clone_for_use_outside_loop( loop, n, worklist );
+            cloned_for_outside_use += clone_for_use_outside_loop(loop, n, worklist);
             sink_list.push(n);
             peel     >>= n->_idx; // delete n from peel set.
             not_peel <<= n->_idx; // add n to not_peel set.
@@ -3254,7 +3250,7 @@
         } else {
           // Otherwise check for special def-use cases that span
           // the peel/not_peel boundary such as bool->if
-          clone_for_special_use_inside_loop( loop, n, not_peel, sink_list, worklist );
+          clone_for_special_use_inside_loop(loop, n, not_peel, sink_list, worklist);
           new_phi_cnt++;
         }
       }
@@ -3262,7 +3258,11 @@
     if (incr) i++;
   }
 
-  if (new_phi_cnt > old_phi_cnt + PartialPeelNewPhiDelta) {
+  estimate += cloned_for_outside_use + new_phi_cnt;
+  bool exceed_node_budget = !may_require_nodes(estimate);
+  bool exceed_phi_limit = new_phi_cnt > old_phi_cnt + PartialPeelNewPhiDelta;
+
+  if (exceed_node_budget || exceed_phi_limit) {
 #ifndef PRODUCT
     if (TracePartialPeeling) {
       tty->print_cr("\nToo many new phis: %d  old %d new cmpi: %c",
@@ -3310,7 +3310,7 @@
 
   const uint clone_exit_idx = 1;
   const uint orig_exit_idx  = 2;
-  assert(is_valid_clone_loop_form( loop, peel_list, orig_exit_idx, clone_exit_idx ), "bad clone loop");
+  assert(is_valid_clone_loop_form(loop, peel_list, orig_exit_idx, clone_exit_idx), "bad clone loop");
 
   Node* head_clone             = old_new[head->_idx];
   LoopNode* new_head_clone     = old_new[new_head->_idx]->as_Loop();
@@ -3318,7 +3318,7 @@
 
   // Add phi if "def" node is in peel set and "use" is not
 
-  for(i = 0; i < peel_list.size(); i++ ) {
+  for (uint i = 0; i < peel_list.size(); i++) {
     Node *def  = peel_list.at(i);
     if (!def->is_CFG()) {
       for (DUIterator_Fast jmax, j = def->fast_outs(jmax); j < jmax; j++) {
@@ -3374,7 +3374,7 @@
   //          cloned-not_peeled  in(0)    in(0)
   //          orig-peeled
 
-  for(i = 0; i < loop->_body.size(); i++ ) {
+  for (uint i = 0; i < loop->_body.size(); i++) {
     Node *n = loop->_body.at(i);
     if (!n->is_CFG()           && n->in(0) != NULL        &&
         not_peel.test(n->_idx) && peel.test(n->in(0)->_idx)) {
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/prims/jni.cpp
--- a/src/hotspot/share/prims/jni.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/prims/jni.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -2909,89 +2909,6 @@
                             HOTSPOT_JNI_SETDOUBLEARRAYREGION_RETURN())
 
 
-//
-// Interception of natives
-//
-
-// The RegisterNatives call being attempted tried to register with a method that
-// is not native.  Ask JVM TI what prefixes have been specified.  Then check
-// to see if the native method is now wrapped with the prefixes.  See the
-// SetNativeMethodPrefix(es) functions in the JVM TI Spec for details.
-static Method* find_prefixed_native(Klass* k, Symbol* name, Symbol* signature, TRAPS) {
-#if INCLUDE_JVMTI
-  ResourceMark rm(THREAD);
-  Method* method;
-  int name_len = name->utf8_length();
-  char* name_str = name->as_utf8();
-  int prefix_count;
-  char** prefixes = JvmtiExport::get_all_native_method_prefixes(&prefix_count);
-  for (int i = 0; i < prefix_count; i++) {
-    char* prefix = prefixes[i];
-    int prefix_len = (int)strlen(prefix);
-
-    // try adding this prefix to the method name and see if it matches another method name
-    int trial_len = name_len + prefix_len;
-    char* trial_name_str = NEW_RESOURCE_ARRAY(char, trial_len + 1);
-    strcpy(trial_name_str, prefix);
-    strcat(trial_name_str, name_str);
-    TempNewSymbol trial_name = SymbolTable::probe(trial_name_str, trial_len);
-    if (trial_name == NULL) {
-      continue; // no such symbol, so this prefix wasn't used, try the next prefix
-    }
-    method = k->lookup_method(trial_name, signature);
-    if (method == NULL) {
-      continue; // signature doesn't match, try the next prefix
-    }
-    if (method->is_native()) {
-      method->set_is_prefixed_native();
-      return method; // wahoo, we found a prefixed version of the method, return it
-    }
-    // found as non-native, so prefix is good, add it, probably just need more prefixes
-    name_len = trial_len;
-    name_str = trial_name_str;
-  }
-#endif // INCLUDE_JVMTI
-  return NULL; // not found
-}
-
-static bool register_native(Klass* k, Symbol* name, Symbol* signature, address entry, TRAPS) {
-  Method* method = k->lookup_method(name, signature);
-  if (method == NULL) {
-    ResourceMark rm;
-    stringStream st;
-    st.print("Method '");
-    Method::print_external_name(&st, k, name, signature);
-    st.print("' name or signature does not match");
-    THROW_MSG_(vmSymbols::java_lang_NoSuchMethodError(), st.as_string(), false);
-  }
-  if (!method->is_native()) {
-    // trying to register to a non-native method, see if a JVM TI agent has added prefix(es)
-    method = find_prefixed_native(k, name, signature, THREAD);
-    if (method == NULL) {
-      ResourceMark rm;
-      stringStream st;
-      st.print("Method '");
-      Method::print_external_name(&st, k, name, signature);
-      st.print("' is not declared as native");
-      THROW_MSG_(vmSymbols::java_lang_NoSuchMethodError(), st.as_string(), false);
-    }
-  }
-
-  if (entry != NULL) {
-    method->set_native_function(entry,
-      Method::native_bind_event_is_interesting);
-  } else {
-    method->clear_native_function();
-  }
-  if (PrintJNIResolving) {
-    ResourceMark rm(THREAD);
-    tty->print_cr("[Registering JNI native method %s.%s]",
-      method->method_holder()->external_name(),
-      method->name()->as_C_string());
-  }
-  return true;
-}
-
 DT_RETURN_MARK_DECL(RegisterNatives, jint
                     , HOTSPOT_JNI_REGISTERNATIVES_RETURN(_ret_ref));
 
@@ -3024,8 +2941,8 @@
       THROW_MSG_(vmSymbols::java_lang_NoSuchMethodError(), st.as_string(), -1);
     }
 
-    bool res = register_native(k, name, signature,
-                               (address) methods[index].fnPtr, THREAD);
+    bool res = Method::register_native(k, name, signature,
+                                       (address) methods[index].fnPtr, THREAD);
     if (!res) {
       ret = -1;
       break;
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/runtime/arguments.cpp
--- a/src/hotspot/share/runtime/arguments.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/runtime/arguments.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -548,6 +548,7 @@
   { "SharedMiscDataSize",            JDK_Version::undefined(), JDK_Version::jdk(10), JDK_Version::undefined() },
   { "SharedMiscCodeSize",            JDK_Version::undefined(), JDK_Version::jdk(10), JDK_Version::undefined() },
   { "CompilationPolicyChoice",       JDK_Version::jdk(13),     JDK_Version::jdk(14), JDK_Version::jdk(15) },
+  { "TraceNMethodInstalls",          JDK_Version::jdk(13),     JDK_Version::jdk(14), JDK_Version::jdk(15) },
   { "FailOverToOldVerifier",         JDK_Version::undefined(), JDK_Version::jdk(14), JDK_Version::jdk(15) },
   { "BindGCTaskThreadsToCPUs",       JDK_Version::undefined(), JDK_Version::jdk(14), JDK_Version::jdk(16) },
   { "UseGCTaskAffinity",             JDK_Version::undefined(), JDK_Version::jdk(14), JDK_Version::jdk(16) },
@@ -593,7 +594,6 @@
   { "TraceSafepointCleanupTime", LogLevel::Info,  true,  LOG_TAGS(safepoint, cleanup) },
   { "TraceJVMTIObjectTagging",   LogLevel::Debug, true,  LOG_TAGS(jvmti, objecttagging) },
   { "TraceRedefineClasses",      LogLevel::Info,  false, LOG_TAGS(redefine, class) },
-  { "TraceNMethodInstalls",      LogLevel::Info,  true,  LOG_TAGS(nmethod, install) },
   { NULL,                        LogLevel::Off,   false, LOG_TAGS(_NO_TAG) }
 };
 
diff -r 72daf2e005cd -r a9316bb4c0e8 src/hotspot/share/runtime/globals.hpp
--- a/src/hotspot/share/runtime/globals.hpp	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/hotspot/share/runtime/globals.hpp	Mon Oct 28 11:21:43 2019 -0400
@@ -563,9 +563,6 @@
   product(bool, PrintExtendedThreadInfo, false,                             \
           "Print more information in thread dump")                          \
                                                                             \
-  diagnostic(bool, TraceNMethodInstalls, false,                             \
-          "Trace nmethod installation")                                     \
-                                                                            \
   diagnostic(intx, ScavengeRootsInCode, 2,                                  \
           "0: do not allow scavengable oops in the code cache; "            \
           "1: allow scavenging from the code cache; "                       \
diff -r 72daf2e005cd -r a9316bb4c0e8 src/java.base/share/classes/java/lang/Object.java
--- a/src/java.base/share/classes/java/lang/Object.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/java.base/share/classes/java/lang/Object.java	Mon Oct 28 11:21:43 2019 -0400
@@ -38,11 +38,6 @@
  */
 public class Object {
 
-    private static native void registerNatives();
-    static {
-        registerNatives();
-    }
-
     /**
      * Constructs a new object.
      */
diff -r 72daf2e005cd -r a9316bb4c0e8 src/java.base/share/classes/java/lang/Thread.java
--- a/src/java.base/share/classes/java/lang/Thread.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/java.base/share/classes/java/lang/Thread.java	Mon Oct 28 11:21:43 2019 -0400
@@ -1075,7 +1075,7 @@
      *   <a href="{@docRoot}/java.base/java/lang/doc-files/threadPrimitiveDeprecation.html">Why
      *   are Thread.stop, Thread.suspend and Thread.resume Deprecated?</a>.
      */
-    @Deprecated(since="1.2")
+    @Deprecated(since="1.2", forRemoval=true)
     public final void suspend() {
         checkAccess();
         suspend0();
@@ -1101,7 +1101,7 @@
      *     <a href="{@docRoot}/java.base/java/lang/doc-files/threadPrimitiveDeprecation.html">Why
      *     are Thread.stop, Thread.suspend and Thread.resume Deprecated?</a>.
      */
-    @Deprecated(since="1.2")
+    @Deprecated(since="1.2", forRemoval=true)
     public final void resume() {
         checkAccess();
         resume0();
diff -r 72daf2e005cd -r a9316bb4c0e8 src/java.base/share/classes/java/lang/ThreadGroup.java
--- a/src/java.base/share/classes/java/lang/ThreadGroup.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/java.base/share/classes/java/lang/ThreadGroup.java	Mon Oct 28 11:21:43 2019 -0400
@@ -666,8 +666,8 @@
      * @deprecated    This method is inherently deadlock-prone.  See
      *     {@link Thread#suspend} for details.
      */
-    @Deprecated(since="1.2")
-    @SuppressWarnings("deprecation")
+    @Deprecated(since="1.2", forRemoval=true)
+    @SuppressWarnings("removal")
     public final void suspend() {
         if (stopOrSuspend(true))
             Thread.currentThread().suspend();
@@ -680,7 +680,7 @@
      * if (and only if) the current thread is found to be in this thread
      * group or one of its subgroups.
      */
-    @SuppressWarnings("deprecation")
+    @SuppressWarnings({"deprecation", "removal"})
     private boolean stopOrSuspend(boolean suspend) {
         boolean suicide = false;
         Thread us = Thread.currentThread();
@@ -729,8 +729,8 @@
      *       both of which have been deprecated, as they are inherently
      *       deadlock-prone.  See {@link Thread#suspend} for details.
      */
-    @Deprecated(since="1.2")
-    @SuppressWarnings("deprecation")
+    @Deprecated(since="1.2", forRemoval=true)
+    @SuppressWarnings("removal")
     public final void resume() {
         int ngroupsSnapshot;
         ThreadGroup[] groupsSnapshot;
@@ -1070,7 +1070,7 @@
      *             which is deprecated.  Further, the behavior of this call
      *             was never specified.
      */
-    @Deprecated(since="1.2")
+    @Deprecated(since="1.2", forRemoval=true)
     public boolean allowThreadSuspension(boolean b) {
         return true;
     }
diff -r 72daf2e005cd -r a9316bb4c0e8 src/java.base/share/classes/java/nio/channels/DatagramChannel.java
--- a/src/java.base/share/classes/java/nio/channels/DatagramChannel.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/java.base/share/classes/java/nio/channels/DatagramChannel.java	Mon Oct 28 11:21:43 2019 -0400
@@ -305,8 +305,10 @@
      *          If the type of the given remote address is not supported
      *
      * @throws  SecurityException
-     *          If a security manager has been installed
-     *          and it does not permit access to the given remote address
+     *          If a security manager has been installed and it does not
+     *          permit access to the given remote address, or if unbound,
+     *          the security manager {@link SecurityManager#checkListen checkListen}
+     *          method denies the operation
      *
      * @throws  IOException
      *          If some other I/O error occurs
@@ -409,6 +411,11 @@
      *          closing the channel and setting the current thread's
      *          interrupt status
      *
+     * @throws  SecurityException
+     *          If unbound, and a security manager has been installed and
+     *          its {@link SecurityManager#checkListen checkListen} method
+     *          denies the operation
+     *
      * @throws  IOException
      *          If some other I/O error occurs
      */
@@ -480,9 +487,10 @@
      *          If the type of the given remote address is not supported
      *
      * @throws  SecurityException
-     *          If a security manager has been installed
-     *          and it does not permit datagrams to be sent
-     *          to the given address
+     *          If a security manager has been installed and it does not permit
+     *          datagrams to be sent to the given address, or if unbound, and
+     *          the security manager's {@link SecurityManager#checkListen checkListen}
+     *          method denies the operation
      *
      * @throws  IOException
      *          If some other I/O error occurs
diff -r 72daf2e005cd -r a9316bb4c0e8 src/java.base/share/classes/sun/nio/ch/DatagramChannelImpl.java
--- a/src/java.base/share/classes/sun/nio/ch/DatagramChannelImpl.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/java.base/share/classes/sun/nio/ch/DatagramChannelImpl.java	Mon Oct 28 11:21:43 2019 -0400
@@ -27,6 +27,8 @@
 
 import java.io.FileDescriptor;
 import java.io.IOException;
+import java.io.UncheckedIOException;
+import java.lang.ref.Cleaner.Cleanable;
 import java.net.DatagramSocket;
 import java.net.Inet4Address;
 import java.net.Inet6Address;
@@ -55,6 +57,7 @@
 import java.util.Set;
 import java.util.concurrent.locks.ReentrantLock;
 
+import jdk.internal.ref.CleanerFactory;
 import sun.net.ResourceManager;
 import sun.net.ext.ExtendedSocketOptions;
 import sun.net.util.IPAddressUtil;
@@ -68,7 +71,7 @@
     implements SelChImpl
 {
     // Used to make native read and write calls
-    private static NativeDispatcher nd = new DatagramDispatcher();
+    private static final NativeDispatcher nd = new DatagramDispatcher();
 
     // The protocol family of the socket
     private final ProtocolFamily family;
@@ -76,6 +79,7 @@
     // Our file descriptor
     private final FileDescriptor fd;
     private final int fdVal;
+    private final Cleanable cleaner;
 
     // Cached InetAddress and port for unconnected DatagramChannels
     // used by receive0
@@ -138,6 +142,7 @@
             ResourceManager.afterUdpClose();
             throw ioe;
         }
+        this.cleaner = CleanerFactory.cleaner().register(this, closerFor(fd));
     }
 
     public DatagramChannelImpl(SelectorProvider sp, ProtocolFamily family)
@@ -164,6 +169,7 @@
             ResourceManager.afterUdpClose();
             throw ioe;
         }
+        this.cleaner = CleanerFactory.cleaner().register(this, closerFor(fd));
     }
 
     public DatagramChannelImpl(SelectorProvider sp, FileDescriptor fd)
@@ -179,6 +185,7 @@
                 : StandardProtocolFamily.INET;
         this.fd = fd;
         this.fdVal = IOUtil.fdVal(fd);
+        this.cleaner = CleanerFactory.cleaner().register(this, closerFor(fd));
         synchronized (stateLock) {
             this.localAddress = Net.localAddress(fd);
         }
@@ -1181,10 +1188,10 @@
         if ((readerThread == 0) && (writerThread == 0) && !isRegistered()) {
             state = ST_CLOSED;
             try {
-                nd.close(fd);
-            } finally {
-                // notify resource manager
-                ResourceManager.afterUdpClose();
+                // close socket
+                cleaner.clean();
+            } catch (UncheckedIOException ioe) {
+                throw ioe.getCause();
             }
             return true;
         } else {
@@ -1283,13 +1290,6 @@
         }
     }
 
-    @SuppressWarnings("deprecation")
-    protected void finalize() throws IOException {
-        // fd is null if constructor threw exception
-        if (fd != null)
-            close();
-    }
-
     /**
      * Translates native poll revent set into a ready operation set
      */
@@ -1377,6 +1377,21 @@
         return fdVal;
     }
 
+    /**
+     * Returns an action to close the given file descriptor.
+     */
+    private static Runnable closerFor(FileDescriptor fd) {
+        return () -> {
+            try {
+                nd.close(fd);
+            } catch (IOException ioe) {
+                throw new UncheckedIOException(ioe);
+            } finally {
+                // decrement
+                ResourceManager.afterUdpClose();
+            }
+        };
+    }
 
     // -- Native methods --
 
diff -r 72daf2e005cd -r a9316bb4c0e8 src/java.base/share/classes/sun/nio/ch/NioSocketImpl.java
--- a/src/java.base/share/classes/sun/nio/ch/NioSocketImpl.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/java.base/share/classes/sun/nio/ch/NioSocketImpl.java	Mon Oct 28 11:21:43 2019 -0400
@@ -30,8 +30,7 @@
 import java.io.InputStream;
 import java.io.OutputStream;
 import java.io.UncheckedIOException;
-import java.lang.invoke.MethodHandles;
-import java.lang.invoke.VarHandle;
+import java.lang.ref.Cleaner.Cleanable;
 import java.net.InetAddress;
 import java.net.InetSocketAddress;
 import java.net.ProtocolFamily;
@@ -106,7 +105,7 @@
 
     // set by SocketImpl.create, protected by stateLock
     private boolean stream;
-    private FileDescriptorCloser closer;
+    private Cleanable cleaner;
 
     // set to true when the socket is in non-blocking mode
     private volatile boolean nonBlocking;
@@ -471,9 +470,10 @@
                     ResourceManager.afterUdpClose();
                 throw ioe;
             }
+            Runnable closer = closerFor(fd, stream);
             this.fd = fd;
             this.stream = stream;
-            this.closer = FileDescriptorCloser.create(this);
+            this.cleaner = CleanerFactory.cleaner().register(this, closer);
             this.state = ST_UNCONNECTED;
         }
     }
@@ -777,10 +777,11 @@
         }
 
         // set the fields
+        Runnable closer = closerFor(newfd, true);
         synchronized (nsi.stateLock) {
             nsi.fd = newfd;
             nsi.stream = true;
-            nsi.closer = FileDescriptorCloser.create(nsi);
+            nsi.cleaner = CleanerFactory.cleaner().register(nsi, closer);
             nsi.localport = localAddress.getPort();
             nsi.address = isaa[0].getAddress();
             nsi.port = isaa[0].getPort();
@@ -850,7 +851,7 @@
         assert Thread.holdsLock(stateLock) && state == ST_CLOSING;
         if (readerThread == 0 && writerThread == 0) {
             try {
-                closer.run();
+                cleaner.clean();
             } catch (UncheckedIOException ioe) {
                 throw ioe.getCause();
             } finally {
@@ -1193,53 +1194,28 @@
     }
 
     /**
-     * A task that closes a SocketImpl's file descriptor. The task runs when the
-     * SocketImpl is explicitly closed and when the SocketImpl becomes phantom
-     * reachable.
+     * Returns an action to close the given file descriptor.
      */
-    private static class FileDescriptorCloser implements Runnable {
-        private static final VarHandle CLOSED;
-        static {
-            try {
-                MethodHandles.Lookup l = MethodHandles.lookup();
-                CLOSED = l.findVarHandle(FileDescriptorCloser.class,
-                                         "closed",
-                                         boolean.class);
-            } catch (Exception e) {
-                throw new InternalError(e);
-            }
-        }
-
-        private final FileDescriptor fd;
-        private final boolean stream;
-        private volatile boolean closed;
-
-        FileDescriptorCloser(FileDescriptor fd, boolean stream) {
-            this.fd = fd;
-            this.stream = stream;
-        }
-
-        static FileDescriptorCloser create(NioSocketImpl impl) {
-            assert Thread.holdsLock(impl.stateLock);
-            var closer = new FileDescriptorCloser(impl.fd, impl.stream);
-            CleanerFactory.cleaner().register(impl, closer);
-            return closer;
-        }
-
-        @Override
-        public void run() {
-            if (CLOSED.compareAndSet(this, false, true)) {
+    private static Runnable closerFor(FileDescriptor fd, boolean stream) {
+        if (stream) {
+            return () -> {
+                try {
+                    nd.close(fd);
+                } catch (IOException ioe) {
+                    throw new UncheckedIOException(ioe);
+                }
+            };
+        } else {
+            return () -> {
                 try {
                     nd.close(fd);
                 } catch (IOException ioe) {
                     throw new UncheckedIOException(ioe);
                 } finally {
-                    if (!stream) {
-                        // decrement
-                        ResourceManager.afterUdpClose();
-                    }
+                    // decrement
+                    ResourceManager.afterUdpClose();
                 }
-            }
+            };
         }
     }
 
diff -r 72daf2e005cd -r a9316bb4c0e8 src/java.base/share/classes/sun/security/tools/KeyStoreUtil.java
--- a/src/java.base/share/classes/sun/security/tools/KeyStoreUtil.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/java.base/share/classes/sun/security/tools/KeyStoreUtil.java	Mon Oct 28 11:21:43 2019 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2005, 2017, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2005, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -304,14 +304,17 @@
     public static void loadProviderByClass(
             String provClass, String arg, ClassLoader cl) {
 
-        // For compatibility, SunPKCS11 and OracleUcrypto can still be
-        // loadable with -providerClass.
+        // For compatibility, SunPKCS11, OracleUcrypto, and SunMSCAPI
+        // can still be loadable with -providerClass.
         if (provClass.equals("sun.security.pkcs11.SunPKCS11")) {
             loadProviderByName("SunPKCS11", arg);
             return;
         } else if (provClass.equals("com.oracle.security.crypto.UcryptoProvider")) {
             loadProviderByName("OracleUcrypto", arg);
             return;
+        } else if (provClass.equals("sun.security.mscapi.SunMSCAPI")) {
+            loadProviderByName("SunMSCAPI", arg);
+            return;
         }
 
         Provider prov;
diff -r 72daf2e005cd -r a9316bb4c0e8 src/java.base/share/native/libjava/Object.c
--- a/src/java.base/share/native/libjava/Object.c	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/java.base/share/native/libjava/Object.c	Mon Oct 28 11:21:43 2019 -0400
@@ -39,21 +39,6 @@
 
 #include "java_lang_Object.h"
 
-static JNINativeMethod methods[] = {
-    {"hashCode",    "()I",                    (void *)&JVM_IHashCode},
-    {"wait",        "(J)V",                   (void *)&JVM_MonitorWait},
-    {"notify",      "()V",                    (void *)&JVM_MonitorNotify},
-    {"notifyAll",   "()V",                    (void *)&JVM_MonitorNotifyAll},
-    {"clone",       "()Ljava/lang/Object;",   (void *)&JVM_Clone},
-};
-
-JNIEXPORT void JNICALL
-Java_java_lang_Object_registerNatives(JNIEnv *env, jclass cls)
-{
-    (*env)->RegisterNatives(env, cls,
-                            methods, sizeof(methods)/sizeof(methods[0]));
-}
-
 JNIEXPORT jclass JNICALL
 Java_java_lang_Object_getClass(JNIEnv *env, jobject this)
 {
diff -r 72daf2e005cd -r a9316bb4c0e8 src/java.management.rmi/share/classes/com/sun/jmx/remote/internal/rmi/ProxyRef.java
--- a/src/java.management.rmi/share/classes/com/sun/jmx/remote/internal/rmi/ProxyRef.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/java.management.rmi/share/classes/com/sun/jmx/remote/internal/rmi/ProxyRef.java	Mon Oct 28 11:21:43 2019 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2003, 2008, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -35,7 +35,8 @@
 import java.rmi.server.RemoteRef;
 
 
-@SuppressWarnings("deprecation")
+@SuppressWarnings({"deprecation",
+                   "serial"}) // Externalizable class w/o no-arg c'tor
 public class ProxyRef implements RemoteRef {
     private static final long serialVersionUID = -6503061366316814723L;
 
diff -r 72daf2e005cd -r a9316bb4c0e8 src/java.management.rmi/share/classes/javax/management/remote/rmi/RMIConnector.java
--- a/src/java.management.rmi/share/classes/javax/management/remote/rmi/RMIConnector.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/java.management.rmi/share/classes/javax/management/remote/rmi/RMIConnector.java	Mon Oct 28 11:21:43 2019 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2002, 2017, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2002, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -2245,6 +2245,7 @@
      *
      * @see #RMIConnector(RMIServer,Map)
      **/
+    @SuppressWarnings("serial") // Not statically typed as Serializable
     private final RMIServer rmiServer;
 
     /**
diff -r 72daf2e005cd -r a9316bb4c0e8 src/java.management/share/classes/javax/management/Attribute.java
--- a/src/java.management/share/classes/javax/management/Attribute.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/java.management/share/classes/javax/management/Attribute.java	Mon Oct 28 11:21:43 2019 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1999, 2005, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1999, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -49,6 +49,7 @@
     /**
      * @serial Attribute value
      */
+    @SuppressWarnings("serial") // Conditionally serializable
     private Object value= null;
 
 
diff -r 72daf2e005cd -r a9316bb4c0e8 src/java.management/share/classes/javax/management/AttributeChangeNotification.java
--- a/src/java.management/share/classes/javax/management/AttributeChangeNotification.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/java.management/share/classes/javax/management/AttributeChangeNotification.java	Mon Oct 28 11:21:43 2019 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1999, 2003, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1999, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -74,11 +74,13 @@
     /**
      * @serial The MBean attribute old value.
      */
+    @SuppressWarnings("serial") // Conditionally serializable
     private Object oldValue = null;
 
     /**
      * @serial The MBean attribute new value.
      */
+    @SuppressWarnings("serial") // Conditionally serializable
     private Object newValue = null;
 
 
diff -r 72daf2e005cd -r a9316bb4c0e8 src/java.management/share/classes/javax/management/BadAttributeValueExpException.java
--- a/src/java.management/share/classes/javax/management/BadAttributeValueExpException.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/java.management/share/classes/javax/management/BadAttributeValueExpException.java	Mon Oct 28 11:21:43 2019 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1999, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -47,6 +47,7 @@
      * @serial A string representation of the attribute that originated this exception.
      * for example, the string value can be the return of {@code attribute.toString()}
      */
+    @SuppressWarnings("serial") // See handling in constructor and readObject
     private Object val;
 
     /**
diff -r 72daf2e005cd -r a9316bb4c0e8 src/java.management/share/classes/javax/management/ImmutableDescriptor.java
--- a/src/java.management/share/classes/javax/management/ImmutableDescriptor.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/java.management/share/classes/javax/management/ImmutableDescriptor.java	Mon Oct 28 11:21:43 2019 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2004, 2015, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2004, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -52,6 +52,7 @@
      * elements in this array match the corresponding elements in the
      * {@code names} array.
      */
+    @SuppressWarnings("serial") // Conditionally serializable
     private final Object[] values;
 
     private transient int hashCode = -1;
diff -r 72daf2e005cd -r a9316bb4c0e8 src/java.management/share/classes/javax/management/InvalidApplicationException.java
--- a/src/java.management/share/classes/javax/management/InvalidApplicationException.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/java.management/share/classes/javax/management/InvalidApplicationException.java	Mon Oct 28 11:21:43 2019 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1999, 2006, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1999, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -44,6 +44,7 @@
     /**
      * @serial The object representing the class of the MBean
      */
+    @SuppressWarnings("serial") // Not statically typed as Serializable
     private Object val;
 
 
diff -r 72daf2e005cd -r a9316bb4c0e8 src/java.management/share/classes/javax/management/NotificationFilterSupport.java
--- a/src/java.management/share/classes/javax/management/NotificationFilterSupport.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/java.management/share/classes/javax/management/NotificationFilterSupport.java	Mon Oct 28 11:21:43 2019 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1999, 2006, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1999, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -64,6 +64,7 @@
      * @serial {@link Vector} that contains the enabled notification types.
      *         The default value is an empty vector.
      */
+    @SuppressWarnings("serial") // Not statically typed as Serializable
     private List<String> enabledTypes = new Vector<String>();
 
 
diff -r 72daf2e005cd -r a9316bb4c0e8 src/java.management/share/classes/javax/management/loading/PrivateMLet.java
--- a/src/java.management/share/classes/javax/management/loading/PrivateMLet.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/java.management/share/classes/javax/management/loading/PrivateMLet.java	Mon Oct 28 11:21:43 2019 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2002, 2007, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2002, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -38,6 +38,7 @@
  *
  * @since 1.5
  */
+@SuppressWarnings("serial") // Externalizable class w/o no-arg c'tor
 public class PrivateMLet extends MLet implements PrivateClassLoader {
     private static final long serialVersionUID = 2503458973393711979L;
 
diff -r 72daf2e005cd -r a9316bb4c0e8 src/java.management/share/classes/javax/management/monitor/MonitorNotification.java
--- a/src/java.management/share/classes/javax/management/monitor/MonitorNotification.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/java.management/share/classes/javax/management/monitor/MonitorNotification.java	Mon Oct 28 11:21:43 2019 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1999, 2007, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1999, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -162,6 +162,7 @@
     /**
      * @serial Monitor notification observed object.
      */
+    @SuppressWarnings("serial") // Not statically typed as Serializable
     private ObjectName observedObject = null;
 
     /**
@@ -172,6 +173,7 @@
     /**
      * @serial Monitor notification derived gauge.
      */
+    @SuppressWarnings("serial") // Not statically typed as Serializable
     private Object derivedGauge = null;
 
     /**
@@ -179,6 +181,7 @@
      *         This value is used to keep the threshold/string (depending on the
      *         monitor type) that triggered off this notification.
      */
+    @SuppressWarnings("serial") // Not statically typed as Serializable
     private Object trigger = null;
 
 
diff -r 72daf2e005cd -r a9316bb4c0e8 src/java.management/share/classes/javax/management/openmbean/CompositeDataSupport.java
--- a/src/java.management/share/classes/javax/management/openmbean/CompositeDataSupport.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/java.management/share/classes/javax/management/openmbean/CompositeDataSupport.java	Mon Oct 28 11:21:43 2019 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2000, 2008, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2000, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -62,6 +62,7 @@
      * respective values.
      *         A {@link SortedMap} is used for faster retrieval of elements.
      */
+    @SuppressWarnings("serial") // Conditionally serializable
     private final SortedMap<String, Object> contents;
 
     /**
diff -r 72daf2e005cd -r a9316bb4c0e8 src/java.management/share/classes/javax/management/openmbean/OpenMBeanAttributeInfoSupport.java
--- a/src/java.management/share/classes/javax/management/openmbean/OpenMBeanAttributeInfoSupport.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/java.management/share/classes/javax/management/openmbean/OpenMBeanAttributeInfoSupport.java	Mon Oct 28 11:21:43 2019 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2000, 2015, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2000, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -64,27 +64,32 @@
     /**
      * @serial The open mbean attribute's <i>open type</i>
      */
+    @SuppressWarnings("serial") // Not statically typed as Serializable
     private OpenType<?> openType;
 
     /**
      * @serial The open mbean attribute's default value
      */
+    @SuppressWarnings("serial") // Not statically typed as Serializable
     private final Object defaultValue;
 
     /**
      * @serial The open mbean attribute's legal values. This {@link
      * Set} is unmodifiable
      */
+    @SuppressWarnings("serial") // Conditionally serializable
     private final Set<?> legalValues;  // to be constructed unmodifiable
 
     /**
      * @serial The open mbean attribute's min value
      */
+    @SuppressWarnings("serial") // Conditionally serializable
     private final Comparable<?> minValue;
 
     /**
      * @serial The open mbean attribute's max value
      */
+    @SuppressWarnings("serial") // Conditionally serializable
     private final Comparable<?> maxValue;
 
 
diff -r 72daf2e005cd -r a9316bb4c0e8 src/java.management/share/classes/javax/management/openmbean/OpenMBeanParameterInfoSupport.java
--- a/src/java.management/share/classes/javax/management/openmbean/OpenMBeanParameterInfoSupport.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/java.management/share/classes/javax/management/openmbean/OpenMBeanParameterInfoSupport.java	Mon Oct 28 11:21:43 2019 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2000, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -58,27 +58,32 @@
     /**
      * @serial The open mbean parameter's <i>open type</i>
      */
+    @SuppressWarnings("serial") // Not statically typed as Serializable
     private OpenType<?>    openType;
 
     /**
      * @serial The open mbean parameter's default value
      */
+    @SuppressWarnings("serial") // Not statically typed as Serializable
     private Object      defaultValue    = null;
 
     /**
      * @serial The open mbean parameter's legal values. This {@link
      * Set} is unmodifiable
      */
+    @SuppressWarnings("serial") // Conditionally serializable
     private Set<?> legalValues     = null;  // to be constructed unmodifiable
 
     /**
      * @serial The open mbean parameter's min value
      */
+    @SuppressWarnings("serial") // Conditionally serializable
     private Comparable<?> minValue        = null;
 
     /**
      * @serial The open mbean parameter's max value
      */
+    @SuppressWarnings("serial") // Conditionally serializable
     private Comparable<?> maxValue        = null;
 
 
diff -r 72daf2e005cd -r a9316bb4c0e8 src/java.management/share/classes/javax/management/openmbean/TabularDataSupport.java
--- a/src/java.management/share/classes/javax/management/openmbean/TabularDataSupport.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/java.management/share/classes/javax/management/openmbean/TabularDataSupport.java	Mon Oct 28 11:21:43 2019 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2000, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -86,6 +86,7 @@
      * @serial This tabular data instance's contents: a {@link HashMap}
      */
     // field cannot be final because of clone method
+    @SuppressWarnings("serial") // Conditionally serializable
     private Map<Object,CompositeData> dataMap;
 
     /**
diff -r 72daf2e005cd -r a9316bb4c0e8 src/java.management/share/classes/javax/management/openmbean/TabularType.java
--- a/src/java.management/share/classes/javax/management/openmbean/TabularType.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/java.management/share/classes/javax/management/openmbean/TabularType.java	Mon Oct 28 11:21:43 2019 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2000, 2014, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2000, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -59,6 +59,7 @@
      * @serial The items used to index each row element, kept in the order the user gave
      *         This is an unmodifiable {@link ArrayList}
      */
+    @SuppressWarnings("serial") // Conditionally serializable
     private List<String> indexNames;
 
 
diff -r 72daf2e005cd -r a9316bb4c0e8 src/java.management/share/classes/sun/management/LazyCompositeData.java
--- a/src/java.management/share/classes/sun/management/LazyCompositeData.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/java.management/share/classes/sun/management/LazyCompositeData.java	Mon Oct 28 11:21:43 2019 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2004, 2015, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2004, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -46,6 +46,7 @@
 public abstract class LazyCompositeData
         implements CompositeData, Serializable {
 
+    @SuppressWarnings("serial") // Not statically typed as Serializable
     private CompositeData compositeData;
 
     // Implementation of the CompositeData interface
diff -r 72daf2e005cd -r a9316bb4c0e8 src/java.management/share/classes/sun/management/LockInfoCompositeData.java
--- a/src/java.management/share/classes/sun/management/LockInfoCompositeData.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/java.management/share/classes/sun/management/LockInfoCompositeData.java	Mon Oct 28 11:21:43 2019 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2012, 2018, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -38,6 +38,7 @@
  * construction of a CompositeData use in the local case.
  */
 public class LockInfoCompositeData extends LazyCompositeData {
+    @SuppressWarnings("serial") // Not statically typed as Serializable
     private final LockInfo lock;
 
     private LockInfoCompositeData(LockInfo li) {
diff -r 72daf2e005cd -r a9316bb4c0e8 src/java.management/share/classes/sun/management/MemoryNotifInfoCompositeData.java
--- a/src/java.management/share/classes/sun/management/MemoryNotifInfoCompositeData.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/java.management/share/classes/sun/management/MemoryNotifInfoCompositeData.java	Mon Oct 28 11:21:43 2019 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2004, 2008, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2004, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -38,6 +38,7 @@
  * construction of a CompositeData use in the local case.
  */
 public class MemoryNotifInfoCompositeData extends LazyCompositeData {
+    @SuppressWarnings("serial") // Not statically typed as Serializable
     private final MemoryNotificationInfo memoryNotifInfo;
 
     private MemoryNotifInfoCompositeData(MemoryNotificationInfo info) {
diff -r 72daf2e005cd -r a9316bb4c0e8 src/java.management/share/classes/sun/management/MemoryUsageCompositeData.java
--- a/src/java.management/share/classes/sun/management/MemoryUsageCompositeData.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/java.management/share/classes/sun/management/MemoryUsageCompositeData.java	Mon Oct 28 11:21:43 2019 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2004, 2008, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2004, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -37,6 +37,7 @@
  * construction of a CompositeData use in the local case.
  */
 public class MemoryUsageCompositeData extends LazyCompositeData {
+    @SuppressWarnings("serial") // Not statically typed as Serializable
     private final MemoryUsage usage;
 
     private MemoryUsageCompositeData(MemoryUsage u) {
diff -r 72daf2e005cd -r a9316bb4c0e8 src/java.management/share/classes/sun/management/MonitorInfoCompositeData.java
--- a/src/java.management/share/classes/sun/management/MonitorInfoCompositeData.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/java.management/share/classes/sun/management/MonitorInfoCompositeData.java	Mon Oct 28 11:21:43 2019 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2005, 2018, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2005, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -40,6 +40,7 @@
  * construction of a CompositeData use in the local case.
  */
 public class MonitorInfoCompositeData extends LazyCompositeData {
+    @SuppressWarnings("serial") // Not statically typed as Serializable
     private final MonitorInfo lock;
 
     private MonitorInfoCompositeData(MonitorInfo mi) {
diff -r 72daf2e005cd -r a9316bb4c0e8 src/java.management/share/classes/sun/management/ThreadInfoCompositeData.java
--- a/src/java.management/share/classes/sun/management/ThreadInfoCompositeData.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/java.management/share/classes/sun/management/ThreadInfoCompositeData.java	Mon Oct 28 11:21:43 2019 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2004, 2018, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2004, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -45,7 +45,9 @@
  * construction of a CompositeData use in the local case.
  */
 public class ThreadInfoCompositeData extends LazyCompositeData {
+    @SuppressWarnings("serial") // Not statically typed as Serializable
     private final ThreadInfo threadInfo;
+    @SuppressWarnings("serial") // Not statically typed as Serializable
     private final CompositeData cdata;
 
     private ThreadInfoCompositeData(ThreadInfo ti) {
diff -r 72daf2e005cd -r a9316bb4c0e8 src/java.management/share/classes/sun/management/counter/perf/PerfByteArrayCounter.java
--- a/src/java.management/share/classes/sun/management/counter/perf/PerfByteArrayCounter.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/java.management/share/classes/sun/management/counter/perf/PerfByteArrayCounter.java	Mon Oct 28 11:21:43 2019 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2003, 2004, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -31,6 +31,7 @@
 public class PerfByteArrayCounter extends AbstractCounter
        implements ByteArrayCounter {
 
+    @SuppressWarnings("serial") // Value indirectly copied as a byte[] in writeReplace
     ByteBuffer bb;
 
     PerfByteArrayCounter(String name, Units u, Variability v,
diff -r 72daf2e005cd -r a9316bb4c0e8 src/java.management/share/classes/sun/management/counter/perf/PerfLongArrayCounter.java
--- a/src/java.management/share/classes/sun/management/counter/perf/PerfLongArrayCounter.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/java.management/share/classes/sun/management/counter/perf/PerfLongArrayCounter.java	Mon Oct 28 11:21:43 2019 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2003, 2004, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -33,6 +33,8 @@
 public class PerfLongArrayCounter extends AbstractCounter
        implements LongArrayCounter {
 
+
+    @SuppressWarnings("serial") // Value indirectly copied as a long[] in writeReplace
     LongBuffer lb;
 
     PerfLongArrayCounter(String name, Units u, Variability v,
diff -r 72daf2e005cd -r a9316bb4c0e8 src/java.management/share/classes/sun/management/counter/perf/PerfLongCounter.java
--- a/src/java.management/share/classes/sun/management/counter/perf/PerfLongCounter.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/java.management/share/classes/sun/management/counter/perf/PerfLongCounter.java	Mon Oct 28 11:21:43 2019 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2003, 2004, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -32,6 +32,7 @@
 public class PerfLongCounter extends AbstractCounter
        implements LongCounter {
 
+    @SuppressWarnings("serial") // Value indirectly copied as a long[] in writeReplace
     LongBuffer lb;
 
     // package private
diff -r 72daf2e005cd -r a9316bb4c0e8 src/java.xml/share/legal/bcel.md
--- a/src/java.xml/share/legal/bcel.md	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/java.xml/share/legal/bcel.md	Mon Oct 28 11:21:43 2019 -0400
@@ -1,4 +1,4 @@
-## Apache Commons Byte Code Engineering Library (BCEL) Version 6.0 
+## Apache Commons Byte Code Engineering Library (BCEL) Version 6.3.1
 
 ### Apache Commons BCEL Notice
 <pre>
diff -r 72daf2e005cd -r a9316bb4c0e8 src/jdk.internal.vm.ci/share/classes/jdk.vm.ci.hotspot/src/jdk/vm/ci/hotspot/CompilerToVM.java
--- a/src/jdk.internal.vm.ci/share/classes/jdk.vm.ci.hotspot/src/jdk/vm/ci/hotspot/CompilerToVM.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/jdk.internal.vm.ci/share/classes/jdk.vm.ci.hotspot/src/jdk/vm/ci/hotspot/CompilerToVM.java	Mon Oct 28 11:21:43 2019 -0400
@@ -967,6 +967,11 @@
     native boolean isCurrentThreadAttached();
 
     /**
+     * @see HotSpotJVMCIRuntime#getCurrentJavaThread()
+     */
+    native long getCurrentJavaThread();
+
+    /**
      * @see HotSpotJVMCIRuntime#attachCurrentThread
      */
     native boolean attachCurrentThread(boolean asDaemon);
diff -r 72daf2e005cd -r a9316bb4c0e8 src/jdk.internal.vm.ci/share/classes/jdk.vm.ci.hotspot/src/jdk/vm/ci/hotspot/HotSpotJVMCIRuntime.java
--- a/src/jdk.internal.vm.ci/share/classes/jdk.vm.ci.hotspot/src/jdk/vm/ci/hotspot/HotSpotJVMCIRuntime.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/jdk.internal.vm.ci/share/classes/jdk.vm.ci.hotspot/src/jdk/vm/ci/hotspot/HotSpotJVMCIRuntime.java	Mon Oct 28 11:21:43 2019 -0400
@@ -999,6 +999,14 @@
     }
 
     /**
+     * Gets the address of the HotSpot {@code JavaThread} C++ object for the current thread. This
+     * will return {@code 0} if called from an unattached JVMCI shared library thread.
+     */
+    public long getCurrentJavaThread() {
+        return compilerToVm.getCurrentJavaThread();
+    }
+
+    /**
      * Ensures the current thread is attached to the peer runtime.
      *
      * @param asDaemon if the thread is not yet attached, should it be attached as a daemon
diff -r 72daf2e005cd -r a9316bb4c0e8 src/jdk.internal.vm.ci/share/classes/jdk.vm.ci.hotspot/src/jdk/vm/ci/hotspot/HotSpotResolvedJavaType.java
--- a/src/jdk.internal.vm.ci/share/classes/jdk.vm.ci.hotspot/src/jdk/vm/ci/hotspot/HotSpotResolvedJavaType.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/jdk.internal.vm.ci/share/classes/jdk.vm.ci.hotspot/src/jdk/vm/ci/hotspot/HotSpotResolvedJavaType.java	Mon Oct 28 11:21:43 2019 -0400
@@ -52,4 +52,13 @@
         }
         return arrayOfType;
     }
+
+    /**
+     * Checks whether this type is currently being initialized. If a type is being initialized it
+     * implies that it was {@link #isLinked() linked} and that the static initializer is currently
+     * being run.
+     *
+     * @return {@code true} if this type is being initialized
+     */
+    abstract boolean isBeingInitialized();
 }
diff -r 72daf2e005cd -r a9316bb4c0e8 src/jdk.internal.vm.ci/share/classes/jdk.vm.ci.hotspot/src/jdk/vm/ci/hotspot/HotSpotResolvedObjectTypeImpl.java
--- a/src/jdk.internal.vm.ci/share/classes/jdk.vm.ci.hotspot/src/jdk/vm/ci/hotspot/HotSpotResolvedObjectTypeImpl.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/jdk.internal.vm.ci/share/classes/jdk.vm.ci.hotspot/src/jdk/vm/ci/hotspot/HotSpotResolvedObjectTypeImpl.java	Mon Oct 28 11:21:43 2019 -0400
@@ -360,6 +360,11 @@
     }
 
     @Override
+    public boolean isBeingInitialized() {
+        return isArray() ? false : getInitState() == config().instanceKlassStateBeingInitialized;
+    }
+
+    @Override
     public boolean isLinked() {
         return isArray() ? true : getInitState() >= config().instanceKlassStateLinked;
     }
@@ -379,7 +384,7 @@
     public void initialize() {
         if (!isInitialized()) {
             runtime().compilerToVm.ensureInitialized(this);
-            assert isInitialized();
+            assert isInitialized() || isBeingInitialized();
         }
     }
 
@@ -578,11 +583,6 @@
             return new AssumptionResult<>(resolvedMethod);
         }
 
-        if (resolvedMethod.canBeStaticallyBound()) {
-            // No assumptions are required.
-            return new AssumptionResult<>(resolvedMethod);
-        }
-
         ResolvedJavaMethod result = resolvedMethod.uniqueConcreteMethod(this);
         if (result != null) {
             return new AssumptionResult<>(result, new ConcreteMethod(method, this, result));
diff -r 72daf2e005cd -r a9316bb4c0e8 src/jdk.internal.vm.ci/share/classes/jdk.vm.ci.hotspot/src/jdk/vm/ci/hotspot/HotSpotResolvedPrimitiveType.java
--- a/src/jdk.internal.vm.ci/share/classes/jdk.vm.ci.hotspot/src/jdk/vm/ci/hotspot/HotSpotResolvedPrimitiveType.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/jdk.internal.vm.ci/share/classes/jdk.vm.ci.hotspot/src/jdk/vm/ci/hotspot/HotSpotResolvedPrimitiveType.java	Mon Oct 28 11:21:43 2019 -0400
@@ -150,6 +150,11 @@
     }
 
     @Override
+    public boolean isBeingInitialized() {
+        return false;
+    }
+
+    @Override
     public boolean isLinked() {
         return true;
     }
diff -r 72daf2e005cd -r a9316bb4c0e8 src/jdk.internal.vm.ci/share/classes/jdk.vm.ci.hotspot/src/jdk/vm/ci/hotspot/HotSpotSpeculationEncoding.java
--- a/src/jdk.internal.vm.ci/share/classes/jdk.vm.ci.hotspot/src/jdk/vm/ci/hotspot/HotSpotSpeculationEncoding.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/jdk.internal.vm.ci/share/classes/jdk.vm.ci.hotspot/src/jdk/vm/ci/hotspot/HotSpotSpeculationEncoding.java	Mon Oct 28 11:21:43 2019 -0400
@@ -29,7 +29,6 @@
 import java.security.NoSuchAlgorithmException;
 import java.util.Arrays;
 
-import jdk.vm.ci.common.JVMCIError;
 import jdk.vm.ci.meta.ResolvedJavaMethod;
 import jdk.vm.ci.meta.ResolvedJavaType;
 import jdk.vm.ci.meta.SpeculationLog.SpeculationReasonEncoding;
@@ -37,8 +36,8 @@
 /**
  * Implements a {@link SpeculationReasonEncoding} that {@linkplain #getByteArray() produces} a byte
  * array. Data is added via a {@link DataOutputStream}. When producing the final byte array, if the
- * total length of data exceeds the length of a SHA-1 digest, then a SHA-1 digest of the data is
- * produced instead.
+ * total length of data exceeds the length of a SHA-1 digest and a SHA-1 digest algorithm is
+ * available, then a SHA-1 digest of the data is produced instead.
  */
 final class HotSpotSpeculationEncoding extends ByteArrayOutputStream implements SpeculationReasonEncoding {
 
@@ -152,21 +151,33 @@
     }
 
     /**
-     * Prototype SHA1 digest that is cloned before use.
+     * Prototype SHA1 digest.
      */
-    private static final MessageDigest SHA1 = getSHA1();
-    private static final int SHA1_LENGTH = SHA1.getDigestLength();
+    private static final MessageDigest SHA1;
 
-    private static MessageDigest getSHA1() {
+    /**
+     * Cloning the prototype is quicker than calling {@link MessageDigest#getInstance(String)} every
+     * time.
+     */
+    private static final boolean SHA1_IS_CLONEABLE;
+    private static final int SHA1_LENGTH;
+
+    static {
+        MessageDigest sha1 = null;
+        boolean sha1IsCloneable = false;
         try {
-            MessageDigest sha1 = MessageDigest.getInstance("SHA-1");
+            sha1 = MessageDigest.getInstance("SHA-1");
             sha1.clone();
-            return sha1;
-        } catch (CloneNotSupportedException | NoSuchAlgorithmException e) {
+            sha1IsCloneable = true;
+        } catch (NoSuchAlgorithmException e) {
             // Should never happen given that SHA-1 is mandated in a
-            // compliant Java platform implementation.
-            throw new JVMCIError("Expect a cloneable implementation of a SHA-1 message digest to be available", e);
+            // compliant Java platform implementation. However, be
+            // conservative and fall back to not using a digest.
+        } catch (CloneNotSupportedException e) {
         }
+        SHA1 = sha1;
+        SHA1_IS_CLONEABLE = sha1IsCloneable;
+        SHA1_LENGTH = SHA1 == null ? 20 : SHA1.getDigestLength();
     }
 
     /**
@@ -175,12 +186,12 @@
      */
     byte[] getByteArray() {
         if (result == null) {
-            if (count > SHA1_LENGTH) {
+            if (SHA1 != null && count > SHA1_LENGTH) {
                 try {
-                    MessageDigest md = (MessageDigest) SHA1.clone();
+                    MessageDigest md = SHA1_IS_CLONEABLE ? (MessageDigest) SHA1.clone() : MessageDigest.getInstance("SHA-1");
                     md.update(buf, 0, count);
                     result = md.digest();
-                } catch (CloneNotSupportedException e) {
+                } catch (CloneNotSupportedException | NoSuchAlgorithmException e) {
                     throw new InternalError(e);
                 }
             } else {
diff -r 72daf2e005cd -r a9316bb4c0e8 src/jdk.internal.vm.ci/share/classes/jdk.vm.ci.hotspot/src/jdk/vm/ci/hotspot/HotSpotVMConfig.java
--- a/src/jdk.internal.vm.ci/share/classes/jdk.vm.ci.hotspot/src/jdk/vm/ci/hotspot/HotSpotVMConfig.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/jdk.internal.vm.ci/share/classes/jdk.vm.ci.hotspot/src/jdk/vm/ci/hotspot/HotSpotVMConfig.java	Mon Oct 28 11:21:43 2019 -0400
@@ -107,6 +107,7 @@
 
     final int instanceKlassStateLinked = getConstant("InstanceKlass::linked", Integer.class);
     final int instanceKlassStateFullyInitialized = getConstant("InstanceKlass::fully_initialized", Integer.class);
+    final int instanceKlassStateBeingInitialized = getConstant("InstanceKlass::being_initialized", Integer.class);
     final int instanceKlassMiscIsUnsafeAnonymous = getConstant("InstanceKlass::_misc_is_unsafe_anonymous", Integer.class);
 
     final int annotationsFieldAnnotationsOffset = getFieldOffset("Annotations::_fields_annotations", Integer.class, "Array<AnnotationArray*>*");
diff -r 72daf2e005cd -r a9316bb4c0e8 src/jdk.internal.vm.ci/share/classes/jdk.vm.ci.hotspot/src/jdk/vm/ci/hotspot/SharedHotSpotSpeculationLog.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/jdk.internal.vm.ci/share/classes/jdk.vm.ci.hotspot/src/jdk/vm/ci/hotspot/SharedHotSpotSpeculationLog.java	Mon Oct 28 11:21:43 2019 -0400
@@ -0,0 +1,42 @@
+/*
+ * Copyright (c) 2014, 2019, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+package jdk.vm.ci.hotspot;
+
+/**
+ * A wrapper that holds a strong reference to a "master" speculation log that
+ * {@linkplain HotSpotSpeculationLog#managesFailedSpeculations() manages} the failed speculations
+ * list.
+ */
+public class SharedHotSpotSpeculationLog extends HotSpotSpeculationLog {
+    private final HotSpotSpeculationLog masterLog;
+
+    public SharedHotSpotSpeculationLog(HotSpotSpeculationLog masterLog) {
+        super(masterLog.getFailedSpeculationsAddress());
+        this.masterLog = masterLog;
+    }
+
+    @Override
+    public String toString() {
+        return masterLog.toString();
+    }
+}
diff -r 72daf2e005cd -r a9316bb4c0e8 src/jdk.internal.vm.ci/share/classes/jdk.vm.ci.meta/src/jdk/vm/ci/meta/EncodedSpeculationReason.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/jdk.internal.vm.ci/share/classes/jdk.vm.ci.meta/src/jdk/vm/ci/meta/EncodedSpeculationReason.java	Mon Oct 28 11:21:43 2019 -0400
@@ -0,0 +1,115 @@
+/*
+ * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+
+package jdk.vm.ci.meta;
+
+import java.util.Arrays;
+import java.util.function.Supplier;
+
+import jdk.vm.ci.meta.SpeculationLog.SpeculationReason;
+
+/**
+ * An implementation of {@link SpeculationReason} based on encoded values.
+ */
+public class EncodedSpeculationReason implements SpeculationReason {
+    final int groupId;
+    final String groupName;
+    final Object[] context;
+    private SpeculationLog.SpeculationReasonEncoding encoding;
+
+    public EncodedSpeculationReason(int groupId, String groupName, Object[] context) {
+        this.groupId = groupId;
+        this.groupName = groupName;
+        this.context = context;
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (obj instanceof EncodedSpeculationReason) {
+            if (obj instanceof EncodedSpeculationReason) {
+                EncodedSpeculationReason that = (EncodedSpeculationReason) obj;
+                return this.groupId == that.groupId && Arrays.equals(this.context, that.context);
+            }
+            return false;
+        }
+        return false;
+    }
+
+    @Override
+    public SpeculationLog.SpeculationReasonEncoding encode(Supplier<SpeculationLog.SpeculationReasonEncoding> encodingSupplier) {
+        if (encoding == null) {
+            encoding = encodingSupplier.get();
+            encoding.addInt(groupId);
+            for (Object o : context) {
+                if (o == null) {
+                    encoding.addInt(0);
+                } else {
+                    addNonNullObject(encoding, o);
+                }
+            }
+        }
+        return encoding;
+    }
+
+    static void addNonNullObject(SpeculationLog.SpeculationReasonEncoding encoding, Object o) {
+        Class<? extends Object> c = o.getClass();
+        if (c == String.class) {
+            encoding.addString((String) o);
+        } else if (c == Byte.class) {
+            encoding.addByte((Byte) o);
+        } else if (c == Short.class) {
+            encoding.addShort((Short) o);
+        } else if (c == Character.class) {
+            encoding.addShort((Character) o);
+        } else if (c == Integer.class) {
+            encoding.addInt((Integer) o);
+        } else if (c == Long.class) {
+            encoding.addLong((Long) o);
+        } else if (c == Float.class) {
+            encoding.addInt(Float.floatToRawIntBits((Float) o));
+        } else if (c == Double.class) {
+            encoding.addLong(Double.doubleToRawLongBits((Double) o));
+        } else if (o instanceof Enum) {
+            encoding.addInt(((Enum<?>) o).ordinal());
+        } else if (o instanceof ResolvedJavaMethod) {
+            encoding.addMethod((ResolvedJavaMethod) o);
+        } else if (o instanceof ResolvedJavaType) {
+            encoding.addType((ResolvedJavaType) o);
+        } else if (o instanceof ResolvedJavaField) {
+            encoding.addField((ResolvedJavaField) o);
+        } else {
+            throw new IllegalArgumentException("Unsupported type for encoding: " + c.getName());
+        }
+    }
+
+    @Override
+    public int hashCode() {
+        return groupId + Arrays.hashCode(this.context);
+    }
+
+    @Override
+    public String toString() {
+        return String.format("%s@%d%s", groupName, groupId, Arrays.toString(context));
+    }
+}
diff -r 72daf2e005cd -r a9316bb4c0e8 src/jdk.management/share/classes/com/sun/management/ThreadMXBean.java
--- a/src/jdk.management/share/classes/com/sun/management/ThreadMXBean.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/src/jdk.management/share/classes/com/sun/management/ThreadMXBean.java	Mon Oct 28 11:21:43 2019 -0400
@@ -122,9 +122,6 @@
      *   {@link #getThreadAllocatedBytes getThreadAllocatedBytes}(Thread.currentThread().getId());
      * </pre></blockquote>
      *
-     * @implSpec The default implementation throws
-     * {@code UnsupportedOperationException}.
-     *
      * @return an approximation of the total memory allocated, in bytes, in
      * heap memory for the current thread
      * if thread memory allocation measurement is enabled;
@@ -141,7 +138,7 @@
      * @since 14
      */
     public default long getCurrentThreadAllocatedBytes() {
-        throw new UnsupportedOperationException();
+        return getThreadAllocatedBytes(Thread.currentThread().getId());
     }
 
     /**
diff -r 72daf2e005cd -r a9316bb4c0e8 test/hotspot/gtest/oops/test_markOop.cpp
--- a/test/hotspot/gtest/oops/test_markOop.cpp	Thu Oct 24 17:14:42 2019 -0400
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,145 +0,0 @@
-/*
- * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
- * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
- *
- * This code is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License version 2 only, as
- * published by the Free Software Foundation.
- *
- * This code is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
- * version 2 for more details (a copy is included in the LICENSE file that
- * accompanied this code).
- *
- * You should have received a copy of the GNU General Public License version
- * 2 along with this work; if not, write to the Free Software Foundation,
- * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
- *
- * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
- * or visit www.oracle.com if you need additional information or have any
- * questions.
- */
-
-#include "precompiled.hpp"
-#include "classfile/systemDictionary.hpp"
-#include "memory/resourceArea.hpp"
-#include "memory/universe.hpp"
-#include "oops/oop.inline.hpp"
-#include "runtime/atomic.hpp"
-#include "runtime/interfaceSupport.inline.hpp"
-#include "runtime/orderAccess.hpp"
-#include "runtime/os.hpp"
-#include "runtime/synchronizer.hpp"
-#include "runtime/semaphore.inline.hpp"
-#include "threadHelper.inline.hpp"
-#include "unittest.hpp"
-#include "utilities/globalDefinitions.hpp"
-#include "utilities/ostream.hpp"
-
-// The test doesn't work for PRODUCT because it needs WizardMode
-#ifndef PRODUCT
-static bool test_pattern(stringStream* st, const char* pattern) {
-  return (strstr(st->as_string(), pattern) != NULL);
-}
-
-static void assert_test_pattern(Handle object, const char* pattern) {
-  stringStream st;
-  object->print_on(&st);
-  ASSERT_TRUE(test_pattern(&st, pattern)) << pattern << " not in " << st.as_string();
-}
-
-static void assert_not_test_pattern(Handle object, const char* pattern) {
-  stringStream st;
-  object->print_on(&st);
-  ASSERT_FALSE(test_pattern(&st, pattern)) << pattern << " found in " << st.as_string();
-}
-
-class LockerThread : public JavaTestThread {
-  oop _obj;
-  public:
-  LockerThread(Semaphore* post, oop obj) : JavaTestThread(post), _obj(obj) {}
-  virtual ~LockerThread() {}
-
-  void main_run() {
-    Thread* THREAD = Thread::current();
-    HandleMark hm(THREAD);
-    Handle h_obj(THREAD, _obj);
-    ResourceMark rm(THREAD);
-
-    // Wait gets the lock inflated.
-    // The object will stay locked for the context of 'ol' so the lock will
-    // still be inflated after the notify_all() call. Deflation can't happen
-    // while an ObjectMonitor is "busy" and being locked is the most "busy"
-    // state we have...
-    ObjectLocker ol(h_obj, THREAD);
-    ol.notify_all(THREAD);
-    assert_test_pattern(h_obj, "monitor");
-  }
-};
-
-
-TEST_VM(markWord, printing) {
-  JavaThread* THREAD = JavaThread::current();
-  ThreadInVMfromNative invm(THREAD);
-  ResourceMark rm(THREAD);
-
-  oop obj = SystemDictionary::Byte_klass()->allocate_instance(THREAD);
-
-  FlagSetting fs(WizardMode, true);
-  FlagSetting bf(UseBiasedLocking, true);
-
-  HandleMark hm(THREAD);
-  Handle h_obj(THREAD, obj);
-
-  // Biased locking is initially enabled for this java.lang.Byte object.
-  assert_test_pattern(h_obj, "is_biased");
-
-  // Lock using biased locking.
-  BasicObjectLock lock;
-  lock.set_obj(obj);
-  markWord prototype_header = obj->klass()->prototype_header();
-  markWord mark = obj->mark();
-  markWord biased_mark = markWord::encode((JavaThread*) THREAD, mark.age(), prototype_header.bias_epoch());
-  obj->set_mark(biased_mark);
-  // Look for the biased_locker in markWord, not prototype_header.
-#ifdef _LP64
-  assert_not_test_pattern(h_obj, "mark(is_biased biased_locker=0x0000000000000000");
-#else
-  assert_not_test_pattern(h_obj, "mark(is_biased biased_locker=0x00000000");
-#endif
-
-  // Same thread tries to lock it again.
-  {
-    ObjectLocker ol(h_obj, THREAD);
-    assert_test_pattern(h_obj, "locked");
-  }
-
-  // This is no longer biased, because ObjectLocker revokes the bias.
-  assert_test_pattern(h_obj, "is_neutral no_hash");
-
-  // Wait gets the lock inflated.
-  {
-    ObjectLocker ol(h_obj, THREAD);
-
-    Semaphore done(0);
-    LockerThread* st;
-    st = new LockerThread(&done, h_obj());
-    st->doit();
-
-    ol.wait(THREAD);
-    assert_test_pattern(h_obj, "monitor");
-    done.wait_with_safepoint_check(THREAD);  // wait till the thread is done.
-  }
-
-  // Make the object older. Not all GCs use this field.
-  Universe::heap()->collect(GCCause::_java_lang_system_gc);
-  if (UseParallelGC) {
-    assert_test_pattern(h_obj, "is_neutral no_hash age 1");
-  }
-
-  // Hash the object then print it.
-  intx hash = h_obj->identity_hash();
-  assert_test_pattern(h_obj, "is_neutral hash=0x");
-}
-#endif // PRODUCT
diff -r 72daf2e005cd -r a9316bb4c0e8 test/hotspot/gtest/oops/test_markWord.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/hotspot/gtest/oops/test_markWord.cpp	Mon Oct 28 11:21:43 2019 -0400
@@ -0,0 +1,150 @@
+/*
+ * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+#include "precompiled.hpp"
+#include "classfile/systemDictionary.hpp"
+#include "memory/resourceArea.hpp"
+#include "memory/universe.hpp"
+#include "oops/oop.inline.hpp"
+#include "runtime/atomic.hpp"
+#include "runtime/biasedLocking.hpp"
+#include "runtime/interfaceSupport.inline.hpp"
+#include "runtime/orderAccess.hpp"
+#include "runtime/os.hpp"
+#include "runtime/synchronizer.hpp"
+#include "runtime/semaphore.inline.hpp"
+#include "threadHelper.inline.hpp"
+#include "unittest.hpp"
+#include "utilities/globalDefinitions.hpp"
+#include "utilities/ostream.hpp"
+
+// The test doesn't work for PRODUCT because it needs WizardMode
+#ifndef PRODUCT
+static bool test_pattern(stringStream* st, const char* pattern) {
+  return (strstr(st->as_string(), pattern) != NULL);
+}
+
+static void assert_test_pattern(Handle object, const char* pattern) {
+  stringStream st;
+  object->print_on(&st);
+  ASSERT_TRUE(test_pattern(&st, pattern)) << pattern << " not in " << st.as_string();
+}
+
+static void assert_not_test_pattern(Handle object, const char* pattern) {
+  stringStream st;
+  object->print_on(&st);
+  ASSERT_FALSE(test_pattern(&st, pattern)) << pattern << " found in " << st.as_string();
+}
+
+class LockerThread : public JavaTestThread {
+  oop _obj;
+  public:
+  LockerThread(Semaphore* post, oop obj) : JavaTestThread(post), _obj(obj) {}
+  virtual ~LockerThread() {}
+
+  void main_run() {
+    Thread* THREAD = Thread::current();
+    HandleMark hm(THREAD);
+    Handle h_obj(THREAD, _obj);
+    ResourceMark rm(THREAD);
+
+    // Wait gets the lock inflated.
+    // The object will stay locked for the context of 'ol' so the lock will
+    // still be inflated after the notify_all() call. Deflation can't happen
+    // while an ObjectMonitor is "busy" and being locked is the most "busy"
+    // state we have...
+    ObjectLocker ol(h_obj, THREAD);
+    ol.notify_all(THREAD);
+    assert_test_pattern(h_obj, "monitor");
+  }
+};
+
+
+TEST_VM(markWord, printing) {
+  JavaThread* THREAD = JavaThread::current();
+  ThreadInVMfromNative invm(THREAD);
+  ResourceMark rm(THREAD);
+
+  if (!UseBiasedLocking || !BiasedLocking::enabled()) {
+    // Can't test this with biased locking disabled.
+    return;
+  }
+
+  oop obj = SystemDictionary::Byte_klass()->allocate_instance(THREAD);
+
+  FlagSetting fs(WizardMode, true);
+
+  HandleMark hm(THREAD);
+  Handle h_obj(THREAD, obj);
+
+  // Biased locking is initially enabled for this java.lang.Byte object.
+  assert_test_pattern(h_obj, "is_biased");
+
+  // Lock using biased locking.
+  BasicObjectLock lock;
+  lock.set_obj(obj);
+  markWord prototype_header = obj->klass()->prototype_header();
+  markWord mark = obj->mark();
+  markWord biased_mark = markWord::encode((JavaThread*) THREAD, mark.age(), prototype_header.bias_epoch());
+  obj->set_mark(biased_mark);
+  // Look for the biased_locker in markWord, not prototype_header.
+#ifdef _LP64
+  assert_not_test_pattern(h_obj, "mark(is_biased biased_locker=0x0000000000000000");
+#else
+  assert_not_test_pattern(h_obj, "mark(is_biased biased_locker=0x00000000");
+#endif
+
+  // Same thread tries to lock it again.
+  {
+    ObjectLocker ol(h_obj, THREAD);
+    assert_test_pattern(h_obj, "locked");
+  }
+
+  // This is no longer biased, because ObjectLocker revokes the bias.
+  assert_test_pattern(h_obj, "is_neutral no_hash");
+
+  // Wait gets the lock inflated.
+  {
+    ObjectLocker ol(h_obj, THREAD);
+
+    Semaphore done(0);
+    LockerThread* st;
+    st = new LockerThread(&done, h_obj());
+    st->doit();
+
+    ol.wait(THREAD);
+    assert_test_pattern(h_obj, "monitor");
+    done.wait_with_safepoint_check(THREAD);  // wait till the thread is done.
+  }
+
+  // Make the object older. Not all GCs use this field.
+  Universe::heap()->collect(GCCause::_java_lang_system_gc);
+  if (UseParallelGC) {
+    assert_test_pattern(h_obj, "is_neutral no_hash age 1");
+  }
+
+  // Hash the object then print it.
+  intx hash = h_obj->identity_hash();
+  assert_test_pattern(h_obj, "is_neutral hash=0x");
+}
+#endif // PRODUCT
diff -r 72daf2e005cd -r a9316bb4c0e8 test/hotspot/jtreg/ProblemList.txt
--- a/test/hotspot/jtreg/ProblemList.txt	Thu Oct 24 17:14:42 2019 -0400
+++ b/test/hotspot/jtreg/ProblemList.txt	Mon Oct 28 11:21:43 2019 -0400
@@ -194,7 +194,6 @@
 vmTestbase/vm/mlvm/indy/func/jvmti/redefineClassInBootstrap/TestDescription.java 8013267 generic-all
 vmTestbase/vm/mlvm/meth/func/java/throwException/Test.java 8058176 generic-all
 vmTestbase/vm/mlvm/meth/func/jdi/breakpointOtherStratum/Test.java 8208257,8058176 generic-all
-vmTestbase/vm/mlvm/meth/stress/compiler/deoptimize/Test.java 8058176 generic-all
 vmTestbase/vm/mlvm/meth/stress/compiler/i2c_c2i/Test.java 8058176 generic-all
 vmTestbase/vm/mlvm/meth/stress/compiler/sequences/Test.java 8058176 generic-all
 vmTestbase/vm/mlvm/meth/stress/gc/callSequencesDuringGC/Test.java 8058176 generic-all
diff -r 72daf2e005cd -r a9316bb4c0e8 test/hotspot/jtreg/compiler/dependencies/MonomorphicObjectCall/java.base/java/lang/Object.java
--- a/test/hotspot/jtreg/compiler/dependencies/MonomorphicObjectCall/java.base/java/lang/Object.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/test/hotspot/jtreg/compiler/dependencies/MonomorphicObjectCall/java.base/java/lang/Object.java	Mon Oct 28 11:21:43 2019 -0400
@@ -34,11 +34,6 @@
     @HotSpotIntrinsicCandidate
     public Object() {}
 
-    private static native void registerNatives();
-    static {
-        registerNatives();
-    }
-
     @HotSpotIntrinsicCandidate
     public final native Class<?> getClass();
 
diff -r 72daf2e005cd -r a9316bb4c0e8 test/hotspot/jtreg/compiler/jvmci/jdk.vm.ci.hotspot.test/src/jdk/vm/ci/hotspot/test/TestHotSpotSpeculationLog.java
--- a/test/hotspot/jtreg/compiler/jvmci/jdk.vm.ci.hotspot.test/src/jdk/vm/ci/hotspot/test/TestHotSpotSpeculationLog.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/test/hotspot/jtreg/compiler/jvmci/jdk.vm.ci.hotspot.test/src/jdk/vm/ci/hotspot/test/TestHotSpotSpeculationLog.java	Mon Oct 28 11:21:43 2019 -0400
@@ -78,7 +78,8 @@
     public synchronized void testFailedSpeculations() {
         HotSpotSpeculationLog log = new HotSpotSpeculationLog();
         DummyReason reason1 = new DummyReason("dummy1");
-        DummyReason reason2 = new DummyReason("dummy2");
+        String longName = new String(new char[2000]).replace('\0', 'X');
+        DummyReason reason2 = new DummyReason(longName);
         Assert.assertTrue(log.maySpeculate(reason1));
         Assert.assertTrue(log.maySpeculate(reason2));
 
diff -r 72daf2e005cd -r a9316bb4c0e8 test/hotspot/jtreg/compiler/loopopts/LoopRotateBadNodeBudget.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/hotspot/jtreg/compiler/loopopts/LoopRotateBadNodeBudget.java	Mon Oct 28 11:21:43 2019 -0400
@@ -0,0 +1,81 @@
+/*
+ * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test
+ * @bug 8231565
+ * @summary Node estimate for loop rotate is not correct/sufficient:
+ *          assert(delta <= 2 * required) failed: Bad node estimate ...
+ *
+ * @requires !vm.graal.enabled
+ *
+ * @run main/othervm -XX:PartialPeelNewPhiDelta=5 LoopRotateBadNodeBudget
+ * @run main/othervm -Xbatch -XX:PartialPeelNewPhiDelta=5 LoopRotateBadNodeBudget
+ *
+ * @run main/othervm LoopRotateBadNodeBudget
+ * @run main/othervm -Xbatch LoopRotateBadNodeBudget
+ *
+ * NOTE: Test-case seldom manifesting the problem on fast machines.
+ */
+
+public class LoopRotateBadNodeBudget {
+
+    int h;
+    float j(int a, int b) {
+        double d = 0.19881;
+        int c, e[] = new int[9];
+        c = 1;
+        while (++c < 12)
+            switch ((c % 7 * 5) + 122) {
+                case 156:
+                case 46128:
+                case 135:
+                case 148:
+                case 127:
+                    break;
+                default:
+            }
+        while ((d += 2) < 62)
+            ;
+        long k = l(e);
+        return k;
+    }
+    long l(int[] a) {
+        long m = 0;
+        for (int i = 0; i < a.length; i++)
+            m = a[i];
+        return m;
+    }
+    void f(String[] g) {
+        int i = 2;
+        for (; i < 20000; ++i)
+            j(3, h);
+    }
+    public static void main(String[] o) {
+        try {
+            LoopRotateBadNodeBudget n = new LoopRotateBadNodeBudget();
+            n.f(o);
+        } catch (Exception ex) {
+        }
+    }
+}
diff -r 72daf2e005cd -r a9316bb4c0e8 test/hotspot/jtreg/gc/g1/TestGCLogMessages.java
--- a/test/hotspot/jtreg/gc/g1/TestGCLogMessages.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/test/hotspot/jtreg/gc/g1/TestGCLogMessages.java	Mon Oct 28 11:21:43 2019 -0400
@@ -128,7 +128,6 @@
         new LogMessageWithLevel("CLDG Roots", Level.TRACE),
         new LogMessageWithLevel("JVMTI Roots", Level.TRACE),
         new LogMessageWithLevel("CM RefProcessor Roots", Level.TRACE),
-        new LogMessageWithLevel("Wait For Strong Roots", Level.TRACE),
         // Redirty Cards
         new LogMessageWithLevel("Redirty Cards", Level.DEBUG),
         new LogMessageWithLevel("Parallel Redirty", Level.TRACE),
diff -r 72daf2e005cd -r a9316bb4c0e8 test/hotspot/jtreg/runtime/8024804/RegisterNatives.java
--- a/test/hotspot/jtreg/runtime/8024804/RegisterNatives.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/test/hotspot/jtreg/runtime/8024804/RegisterNatives.java	Mon Oct 28 11:21:43 2019 -0400
@@ -23,15 +23,27 @@
 
 /*
  * @test
- * @bug 8024804
- * @bug 8028741
+ * @bug 8024804 8028741 8232613
  * @summary interface method resolution should skip finding j.l.Object's registerNatives() and succeed in selecting class B's registerNatives()
  * @run main RegisterNatives
  */
 public class RegisterNatives {
-  interface I { void registerNatives(); }
+  interface I {
+    void registerNatives();
+  }
+
   interface J extends I {}
-  static class B implements J { public void registerNatives() { System.out.println("B"); } }
+
+  interface K {
+    default public void registerNatives() { System.out.println("K"); }
+  }
+
+  static class B implements J {
+    public void registerNatives() { System.out.println("B"); }
+  }
+
+  static class C implements K {}
+
   public static void main(String... args) {
     System.out.println("Regression test for JDK-8024804, crash when InterfaceMethodref resolves to Object.registerNatives\n");
     J val = new B();
@@ -42,6 +54,14 @@
       e.printStackTrace();
       throw e;
     }
+    C cval = new C();
+    try {
+      cval.registerNatives();
+    } catch (IllegalAccessError e) {
+      System.out.println("TEST FAILS - a default method named registerNatives should no longer be masked by removed Object.registerNatives\n");
+      e.printStackTrace();
+      throw e;
+    }
     System.out.println("TEST PASSES - no IAE resulted\n");
   }
 }
diff -r 72daf2e005cd -r a9316bb4c0e8 test/hotspot/jtreg/serviceability/jvmti/RedefineClasses/RedefineObject.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/hotspot/jtreg/serviceability/jvmti/RedefineClasses/RedefineObject.java	Mon Oct 28 11:21:43 2019 -0400
@@ -0,0 +1,177 @@
+/*
+ * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test
+ * @bug 8232613
+ * @summary Ensure Object natives stay registered after redefinition
+ * @library /test/lib
+ * @modules java.base/jdk.internal.misc
+ *          java.base/jdk.internal.org.objectweb.asm
+ *          java.compiler
+ *          java.instrument
+ *          jdk.jartool/sun.tools.jar
+ * @run main RedefineObject buildagent
+ * @run main/othervm -javaagent:redefineagent.jar RedefineObject
+ */
+
+import static jdk.test.lib.Asserts.assertTrue;
+import java.io.FileNotFoundException;
+import java.io.PrintWriter;
+import java.lang.RuntimeException;
+import java.lang.instrument.ClassFileTransformer;
+import java.lang.instrument.IllegalClassFormatException;
+import java.lang.instrument.Instrumentation;
+import java.lang.instrument.UnmodifiableClassException;
+import java.security.ProtectionDomain;
+import java.util.Arrays;
+
+import jdk.internal.org.objectweb.asm.ClassReader;
+import jdk.internal.org.objectweb.asm.ClassVisitor;
+import jdk.internal.org.objectweb.asm.ClassWriter;
+
+import static jdk.internal.org.objectweb.asm.Opcodes.ASM6;
+import static jdk.internal.org.objectweb.asm.Opcodes.V1_8;
+
+public class RedefineObject {
+
+    static Instrumentation inst;
+
+    public static void premain(String agentArgs, Instrumentation inst) {
+        RedefineObject.inst = inst;
+    }
+
+    static class Transformer implements ClassFileTransformer {
+
+        public byte[] asm(ClassLoader loader, String className,
+                          Class<?> classBeingRedefined,
+                          ProtectionDomain protectionDomain, byte[] classfileBuffer)
+                throws IllegalClassFormatException {
+            ClassWriter cw = new ClassWriter(0);
+            // Force an older ASM to force a bytecode update
+            ClassVisitor cv = new DummyClassVisitor(ASM6, cw) { };
+            ClassReader cr = new ClassReader(classfileBuffer);
+            cr.accept(cv, 0);
+            byte[] bytes = cw.toByteArray();
+            return bytes;
+        }
+
+        public class DummyClassVisitor extends ClassVisitor {
+
+            public DummyClassVisitor(int api, ClassVisitor cv) {
+                super(api, cv);
+            }
+
+            public void visit(
+                    final int version,
+                    final int access,
+                    final String name,
+                    final String signature,
+                    final String superName,
+                    final String[] interfaces) {
+                // Artificially lower to JDK 8 version to force a redefine
+                cv.visit(V1_8, access, name, signature, superName, interfaces);
+            }
+        }
+
+        @Override public byte[] transform(ClassLoader loader, String className,
+                                          Class<?> classBeingRedefined,
+                                          ProtectionDomain protectionDomain, byte[] classfileBuffer)
+                throws IllegalClassFormatException {
+
+            if (className.contains("java/lang/Object")) {
+                try {
+                    // Here we remove and re-add the dummy fields. This shuffles the constant pool
+                    return asm(loader, className, classBeingRedefined, protectionDomain, classfileBuffer);
+                } catch (Throwable e) {
+                    // The retransform native code that called this method does not propagate
+                    // exceptions. Instead of getting an uninformative generic error, catch
+                    // problems here and print it, then exit.
+                    e.printStackTrace();
+                    System.exit(1);
+                }
+            }
+            return null;
+        }
+    }
+
+    private static void buildAgent() {
+        try {
+            ClassFileInstaller.main("RedefineObject");
+        } catch (Exception e) {
+            throw new RuntimeException("Could not write agent classfile", e);
+        }
+
+        try {
+            PrintWriter pw = new PrintWriter("MANIFEST.MF");
+            pw.println("Premain-Class: RedefineObject");
+            pw.println("Agent-Class: RedefineObject");
+            pw.println("Can-Retransform-Classes: true");
+            pw.close();
+        } catch (FileNotFoundException e) {
+            throw new RuntimeException("Could not write manifest file for the agent", e);
+        }
+
+        sun.tools.jar.Main jarTool = new sun.tools.jar.Main(System.out, System.err, "jar");
+        if (!jarTool.run(new String[] { "-cmf", "MANIFEST.MF", "redefineagent.jar", "RedefineObject.class" })) {
+            throw new RuntimeException("Could not write the agent jar file");
+        }
+    }
+
+    public static void main(String[] args) throws Exception {
+
+        int objHash = System.identityHashCode(Object.class);
+        System.out.println("Object hashCode: " + objHash);
+        if (args.length == 1 && args[0].equals("buildagent")) {
+            buildAgent();
+            return;
+        }
+
+        if (inst == null) {
+            throw new RuntimeException("Instrumentation object was null");
+        }
+
+        try {
+            inst.addTransformer(new RedefineObject.Transformer(), true);
+            inst.retransformClasses(Object.class);
+        } catch (UnmodifiableClassException e) {
+            throw new RuntimeException(e);
+        }
+
+        // Exercise native methods on Object after transform
+        Object b = new Object();
+        b.hashCode();
+
+        C c = new C();
+        assertTrue(c.hashCode() != c.clone().hashCode() || c != c.clone());
+        assertTrue(c.clone() instanceof C);
+        c = (C)c.clone(); // native method on new Object
+    }
+
+    private static class C implements Cloneable {
+        @Override
+        protected Object clone() throws CloneNotSupportedException {
+            return super.clone();
+        }
+    }
+}
diff -r 72daf2e005cd -r a9316bb4c0e8 test/hotspot/jtreg/vmTestbase/nsk/jvmti/Allocate/alloc001/TestDescription.java
--- a/test/hotspot/jtreg/vmTestbase/nsk/jvmti/Allocate/alloc001/TestDescription.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/test/hotspot/jtreg/vmTestbase/nsk/jvmti/Allocate/alloc001/TestDescription.java	Mon Oct 28 11:21:43 2019 -0400
@@ -42,8 +42,6 @@
  * @library /vmTestbase
  *          /test/lib
  * @requires os.family != "aix"
- * @comment Test is incompatible with ZGC, due to ZGC's address space requirements.
- * @requires vm.gc != "Z"
  * @run driver jdk.test.lib.FileInstaller . .
  * @build nsk.jvmti.Allocate.alloc001
  * @run shell alloc001.sh
diff -r 72daf2e005cd -r a9316bb4c0e8 test/hotspot/jtreg/vmTestbase/nsk/jvmti/scenarios/bcinstr/BI04/bi04t002/newclass02/java.base/java/lang/Object.java
--- a/test/hotspot/jtreg/vmTestbase/nsk/jvmti/scenarios/bcinstr/BI04/bi04t002/newclass02/java.base/java/lang/Object.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/test/hotspot/jtreg/vmTestbase/nsk/jvmti/scenarios/bcinstr/BI04/bi04t002/newclass02/java.base/java/lang/Object.java	Mon Oct 28 11:21:43 2019 -0400
@@ -37,11 +37,6 @@
  */
 public class Object {
 
-    private static native void registerNatives();
-    static {
-        registerNatives();
-    }
-
     /**
      * Returns the runtime class of an object. That <tt>Class</tt>
      * object is the object that is locked by <tt>static synchronized</tt>
diff -r 72daf2e005cd -r a9316bb4c0e8 test/hotspot/jtreg/vmTestbase/vm/mlvm/meth/stress/compiler/deoptimize/Test.java
--- a/test/hotspot/jtreg/vmTestbase/vm/mlvm/meth/stress/compiler/deoptimize/Test.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/test/hotspot/jtreg/vmTestbase/vm/mlvm/meth/stress/compiler/deoptimize/Test.java	Mon Oct 28 11:21:43 2019 -0400
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2011, 2018, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2011, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -24,6 +24,7 @@
 
 /*
  * @test
+ * @key stress
  *
  * @summary converted from VM Testbase vm/mlvm/meth/stress/compiler/deoptimize.
  * VM Testbase keywords: [feature_mlvm, nonconcurrent, quarantine]
@@ -42,6 +43,8 @@
  * @build vm.mlvm.meth.stress.compiler.deoptimize.Test
  * @run driver vm.mlvm.share.IndifiedClassesBuilder
  *
+ * @requires vm.debug != true
+ *
  * @run main/othervm
  *      -XX:ReservedCodeCacheSize=100m
  *      vm.mlvm.meth.stress.compiler.deoptimize.Test
@@ -49,6 +52,29 @@
  *      -threadsExtra 2
  */
 
+
+/*
+ * @test
+ * @key stress
+ *
+ * @library /vmTestbase
+ *          /test/lib
+ * @run driver jdk.test.lib.FileInstaller . .
+ *
+ * @comment build test class and indify classes
+ * @build vm.mlvm.meth.stress.compiler.deoptimize.Test
+ * @run driver vm.mlvm.share.IndifiedClassesBuilder
+ *
+ * @requires vm.debug == true
+ *
+ * @run main/othervm
+ *      -XX:ReservedCodeCacheSize=100m
+ *      vm.mlvm.meth.stress.compiler.deoptimize.Test
+ *      -threadsPerCpu 2
+ *      -threadsExtra 2
+ */
+
+
 package vm.mlvm.meth.stress.compiler.deoptimize;
 
 import java.lang.invoke.MethodHandle;
diff -r 72daf2e005cd -r a9316bb4c0e8 test/jdk/ProblemList-Xcomp.txt
--- a/test/jdk/ProblemList-Xcomp.txt	Thu Oct 24 17:14:42 2019 -0400
+++ b/test/jdk/ProblemList-Xcomp.txt	Mon Oct 28 11:21:43 2019 -0400
@@ -29,3 +29,4 @@
 
 java/lang/invoke/MethodHandles/CatchExceptionTest.java 8146623 generic-all
 java/util/stream/test/org/openjdk/tests/java/util/stream/StreamLinkTest.java 8216317 solaris-all
+java/math/BigInteger/largeMemory/SymmetricRangeTests.java 8232840 generic-all
diff -r 72daf2e005cd -r a9316bb4c0e8 test/jdk/ProblemList.txt
--- a/test/jdk/ProblemList.txt	Thu Oct 24 17:14:42 2019 -0400
+++ b/test/jdk/ProblemList.txt	Mon Oct 28 11:21:43 2019 -0400
@@ -890,6 +890,4 @@
 
 # jdk_internal
 
-jdk/internal/platform/docker/TestDockerMemoryMetrics.java       8227317    linux-x64
-
 ############################################################################
diff -r 72daf2e005cd -r a9316bb4c0e8 test/jdk/java/nio/channels/DatagramChannel/Unref.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/jdk/java/nio/channels/DatagramChannel/Unref.java	Mon Oct 28 11:21:43 2019 -0400
@@ -0,0 +1,170 @@
+/*
+ * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/**
+ * @test
+ * @bug 8212132
+ * @summary Test that DatagramChannel does not leak file descriptors
+ * @requires os.family != "windows"
+ * @modules jdk.management
+ * @library /test/lib
+ * @run main/othervm Unref
+ */
+
+import java.io.IOException;
+import java.lang.management.ManagementFactory;
+import java.net.InetSocketAddress;
+import java.net.StandardProtocolFamily;
+import java.nio.channels.DatagramChannel;
+import java.nio.channels.SelectionKey;
+import java.nio.channels.Selector;
+
+import com.sun.management.UnixOperatingSystemMXBean;
+
+import jtreg.SkippedException;
+import jdk.test.lib.net.IPSupport;
+
+public class Unref {
+
+    interface DatagramChannelSupplier {
+        DatagramChannel get() throws IOException;
+    }
+
+    public static void main(String[] args) throws Exception {
+        if (unixOperatingSystemMXBean() == null)
+            throw new SkippedException("This test requires UnixOperatingSystemMXBean");
+
+        test(DatagramChannel::open);
+        if (IPSupport.hasIPv4())
+            test(() -> DatagramChannel.open(StandardProtocolFamily.INET));
+        if (IPSupport.hasIPv6())
+            test(() -> DatagramChannel.open(StandardProtocolFamily.INET6));
+    }
+
+    static void test(DatagramChannelSupplier supplier) throws Exception {
+        openAndClose(supplier); // warm-up
+
+        try (Selector sel = Selector.open()) {
+            long count = fileDescriptorCount();
+
+            // open+close
+            openAndClose(supplier);
+            assertEquals(fileDescriptorCount(), count);
+
+            // open+unref, file descriptor should be closed by cleaner
+            openAndUnref(supplier);
+            assertEquals(waitForFileDescriptorCount(count), count);
+
+            // open+register+close+flush
+            openRegisterAndClose(supplier, sel);
+            assertEquals(fileDescriptorCount(), count);
+
+            // open+register+flush, file descriptor should be closed by cleaner
+            openRegisterAndUnref(supplier, sel);
+            assertEquals(waitForFileDescriptorCount(count), count);
+        }
+    }
+
+    /**
+     * Create a DatagramChannel and closes it.
+     */
+    static void openAndClose(DatagramChannelSupplier supplier) throws IOException {
+        System.out.println("openAndClose ...");
+        DatagramChannel dc = supplier.get();
+        dc.close();
+    }
+
+    /**
+     * Create a DatagramChannel and exits without closing the channel.
+     */
+    static void openAndUnref(DatagramChannelSupplier supplier) throws IOException {
+        System.out.println("openAndUnref ...");
+        DatagramChannel dc = supplier.get();
+    }
+
+    /**
+     * Create a DatagramChannel, register it with a Selector, close the channel
+     * while register, and then finally flush the channel from the Selector.
+     */
+    static void openRegisterAndClose(DatagramChannelSupplier supplier, Selector sel)
+        throws IOException
+    {
+        System.out.println("openRegisterAndClose ...");
+        try (DatagramChannel dc = supplier.get()) {
+            dc.bind(new InetSocketAddress(0));
+            dc.configureBlocking(false);
+            dc.register(sel, SelectionKey.OP_READ);
+            sel.selectNow();
+        }
+
+        // flush, should close channel
+        sel.selectNow();
+    }
+
+    /**
+     * Creates a DatagramChannel, registers with a Selector, cancels the key
+     * and flushes the channel from the Selector. This method exits without
+     * closing the channel.
+     */
+    static void openRegisterAndUnref(DatagramChannelSupplier supplier, Selector sel)
+        throws IOException
+    {
+        System.out.println("openRegisterAndUnref ...");
+        DatagramChannel dc = supplier.get();
+        dc.bind(new InetSocketAddress(0));
+        dc.configureBlocking(false);
+        SelectionKey key = dc.register(sel, SelectionKey.OP_READ);
+        sel.selectNow();
+        key.cancel();
+        sel.selectNow();
+    }
+
+    /**
+     * If the file descriptor count is higher than the given count then invoke
+     * System.gc() and wait for the file descriptor count to drop.
+     */
+    static long waitForFileDescriptorCount(long target) throws InterruptedException {
+        long actual = fileDescriptorCount();
+        if (actual > target) {
+            System.gc();
+            while ((actual = fileDescriptorCount()) > target) {
+                Thread.sleep(10);
+            }
+        }
+        return actual;
+    }
+
+    static UnixOperatingSystemMXBean unixOperatingSystemMXBean() {
+        return ManagementFactory.getPlatformMXBean(UnixOperatingSystemMXBean.class);
+    }
+
+    static long fileDescriptorCount() {
+        return unixOperatingSystemMXBean().getOpenFileDescriptorCount();
+    }
+
+    static void assertEquals(long actual, long expected) {
+        if (actual != expected)
+            throw new RuntimeException("actual=" + actual + ", expected=" + expected);
+    }
+}
+
diff -r 72daf2e005cd -r a9316bb4c0e8 test/jdk/jdk/internal/platform/docker/TestDockerMemoryMetrics.java
--- a/test/jdk/jdk/internal/platform/docker/TestDockerMemoryMetrics.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/test/jdk/jdk/internal/platform/docker/TestDockerMemoryMetrics.java	Mon Oct 28 11:21:43 2019 -0400
@@ -25,6 +25,7 @@
 import jdk.test.lib.containers.docker.Common;
 import jdk.test.lib.containers.docker.DockerRunOptions;
 import jdk.test.lib.containers.docker.DockerTestUtils;
+import jdk.test.lib.process.OutputAnalyzer;
 
 /*
  * @test
@@ -119,7 +120,19 @@
                 .addJavaOpts("-cp", "/test-classes/")
                 .addJavaOpts("--add-exports", "java.base/jdk.internal.platform=ALL-UNNAMED")
                 .addClassOptions("kernelmem", value);
-        DockerTestUtils.dockerRunJava(opts).shouldHaveExitValue(0).shouldContain("TEST PASSED!!!");
+        OutputAnalyzer oa = DockerTestUtils.dockerRunJava(opts);
+
+        // Some container runtimes (e.g. runc, docker 18.09)
+        // have been built without kernel memory accounting. In
+        // that case, the runtime issues a message on stderr saying
+        // so. Skip the test in that case.
+        if (oa.getStderr().contains("kernel memory accounting disabled")) {
+            System.out.println("Kernel memory accounting disabled, " +
+                                       "skipping the test case");
+            return;
+        }
+
+        oa.shouldHaveExitValue(0).shouldContain("TEST PASSED!!!");
     }
 
     private static void testOomKillFlag(String value, boolean oomKillFlag) throws Exception {
diff -r 72daf2e005cd -r a9316bb4c0e8 test/jdk/jdk/jfr/event/gc/collection/TestG1ParallelPhases.java
--- a/test/jdk/jdk/jfr/event/gc/collection/TestG1ParallelPhases.java	Thu Oct 24 17:14:42 2019 -0400
+++ b/test/jdk/jdk/jfr/event/gc/collection/TestG1ParallelPhases.java	Mon Oct 28 11:21:43 2019 -0400
@@ -98,7 +98,6 @@
             "CLDGRoots",
             "JVMTIRoots",
             "CMRefRoots",
-            "WaitForStrongRoots",
             "MergeER",
             "MergeHCC",
             "MergeRS",
diff -r 72daf2e005cd -r a9316bb4c0e8 test/jdk/jdk/jfr/jvm/TestClearStaleConstants.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/jdk/jdk/jfr/jvm/TestClearStaleConstants.java	Mon Oct 28 11:21:43 2019 -0400
@@ -0,0 +1,115 @@
+/*
+ * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package jdk.jfr.jvm;
+
+import java.time.Duration;
+import java.util.List;
+
+import jdk.jfr.consumer.RecordedClass;
+import jdk.jfr.consumer.RecordedClassLoader;
+import jdk.jfr.consumer.RecordedEvent;
+import jdk.jfr.internal.JVM;
+import jdk.jfr.Recording;
+import jdk.test.lib.Asserts;
+import jdk.test.lib.jfr.EventNames;
+import jdk.test.lib.jfr.Events;
+import jdk.test.lib.jfr.TestClassLoader;
+
+/**
+ * @test
+ * @bug 8231081
+ * @key jfr
+ * @requires vm.hasJFR
+ * @modules jdk.jfr/jdk.jfr.internal
+ * @library /test/lib /test/jdk
+ * @run main/othervm -Xlog:class+unload -Xlog:gc -Xmx16m jdk.jfr.jvm.TestClearStaleConstants
+ */
+
+/**
+ * System.gc() will trigger class unloading if -XX:+ExplicitGCInvokesConcurrent is NOT set.
+ * If this flag is set G1 will never unload classes on System.gc() and
+ * As far as the "jfr" key guarantees no VM flags are set from the outside
+ * it should be enough with System.gc().
+ */
+public final class TestClearStaleConstants {
+    static class MyClass {
+    }
+    private final static String TEST_CLASS_NAME = "jdk.jfr.jvm.TestClearStaleConstants$MyClass";
+    private final static String EVENT_NAME = EventNames.ClassDefine;
+
+    // to prevent the compiler to optimize away all unread writes
+    public static TestClassLoader firstClassLoader;
+    public static TestClassLoader secondClassLoader;
+
+    public static void main(String... args) throws Exception {
+        firstClassLoader = new TestClassLoader();
+        // define a  class using a class loader under a recording
+        Class<?> clz = recordClassDefinition(firstClassLoader);
+        JVM jvm = JVM.getJVM();
+        // we will now tag the defined and loaded clz as being in use (no recordings are running here)
+        jvm.getClassIdNonIntrinsic(clz);
+        // null out for unload to occur
+        firstClassLoader = null;
+        clz = null;
+        // provoke unload
+        System.gc();
+        // try to define another class _with the same name_ using a different class loader
+        secondClassLoader = new TestClassLoader();
+        // this will throw a NPE for 8231081 because it will reuse the same class name
+        // that symbol was  marked as already serialized by the unload, but since no recordings were running
+        // it was not written to any chunk. This creates a reference to a non-existing symbol, leading to an NPE (no symbol at the expected location).
+        recordClassDefinition(secondClassLoader);
+    }
+
+    private static Class<?> recordClassDefinition(TestClassLoader classLoader) throws Exception  {
+        try (Recording recording = new Recording())  {
+            recording.enable(EVENT_NAME);
+            recording.start();
+            Class<?> clz = classLoader.loadClass(TEST_CLASS_NAME);
+            recording.stop();
+            assertClassDefineEvent(recording);
+            return clz;
+        }
+    }
+
+    private static void assertClassDefineEvent(Recording recording) throws Exception {
+        boolean isAnyFound = false;
+        for (RecordedEvent event : Events.fromRecording(recording)) {
+            System.out.println(event);
+            RecordedClass definedClass = event.getValue("definedClass");
+            if (TEST_CLASS_NAME.equals(definedClass.getName())) {
+                RecordedClassLoader definingClassLoader = definedClass.getClassLoader();
+                String definingName = definingClassLoader.getType().getName();
+                String testName = TestClassLoader.class.getName();
+                String errorMsg = "Expected " + testName + ", got " + definingName;
+                Asserts.assertEquals(testName, definingName, errorMsg);
+                Asserts.assertFalse(isAnyFound, "Found more than 1 event");
+                isAnyFound = true;
+            }
+        }
+        Asserts.assertTrue(isAnyFound, "No events found");
+    }
+}
diff -r 72daf2e005cd -r a9316bb4c0e8 test/jdk/sun/security/mscapi/ProviderClassOption.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/jdk/sun/security/mscapi/ProviderClassOption.java	Mon Oct 28 11:21:43 2019 -0400
@@ -0,0 +1,40 @@
+/*
+ * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test
+ * @bug 8231598
+ * @requires os.family == "windows"
+ * @library /test/lib
+ * @summary keytool does not export sun.security.mscapi
+ */
+
+import jdk.test.lib.SecurityTools;
+
+public class ProviderClassOption {
+    public static void main(String[] args) throws Throwable {
+        SecurityTools.keytool("-v -storetype Windows-ROOT -list"
+                + " -providerClass sun.security.mscapi.SunMSCAPI")
+            .shouldHaveExitValue(0);
+    }
+}