--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/cpu/aarch64/gc/shenandoah/shenandoahBarrierSetAssembler_aarch64.cpp Mon Dec 10 15:47:44 2018 +0100
@@ -0,0 +1,671 @@
+/*
+ * Copyright (c) 2018, Red Hat, Inc. All rights reserved.
+ *
+ * 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/shenandoah/shenandoahBarrierSetAssembler.hpp"
+#include "gc/shenandoah/shenandoahHeap.hpp"
+#include "gc/shenandoah/shenandoahHeapRegion.hpp"
+#include "gc/shenandoah/shenandoahHeuristics.hpp"
+#include "gc/shenandoah/shenandoahRuntime.hpp"
+#include "gc/shenandoah/shenandoahThreadLocalData.hpp"
+#include "interpreter/interpreter.hpp"
+#include "interpreter/interp_masm.hpp"
+#include "runtime/sharedRuntime.hpp"
+#include "runtime/thread.hpp"
+#ifdef COMPILER1
+#include "c1/c1_LIRAssembler.hpp"
+#include "c1/c1_MacroAssembler.hpp"
+#include "gc/shenandoah/c1/shenandoahBarrierSetC1.hpp"
+#endif
+
+#define __ masm->
+
+address ShenandoahBarrierSetAssembler::_shenandoah_wb = NULL;
+
+void ShenandoahBarrierSetAssembler::arraycopy_prologue(MacroAssembler* masm, DecoratorSet decorators, bool is_oop,
+ Register addr, Register count, RegSet saved_regs) {
+ if (is_oop) {
+ bool dest_uninitialized = (decorators & IS_DEST_UNINITIALIZED) != 0;
+ if (!dest_uninitialized && !ShenandoahHeap::heap()->heuristics()->can_do_traversal_gc()) {
+ __ push(saved_regs, sp);
+ if (count == c_rarg0) {
+ if (addr == c_rarg1) {
+ // exactly backwards!!
+ __ mov(rscratch1, c_rarg0);
+ __ mov(c_rarg0, c_rarg1);
+ __ mov(c_rarg1, rscratch1);
+ } else {
+ __ mov(c_rarg1, count);
+ __ mov(c_rarg0, addr);
+ }
+ } else {
+ __ mov(c_rarg0, addr);
+ __ mov(c_rarg1, count);
+ }
+ if (UseCompressedOops) {
+ __ call_VM_leaf(CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_ref_array_pre_narrow_oop_entry), 2);
+ } else {
+ __ call_VM_leaf(CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_ref_array_pre_oop_entry), 2);
+ }
+ __ pop(saved_regs, sp);
+ }
+ }
+}
+
+void ShenandoahBarrierSetAssembler::arraycopy_epilogue(MacroAssembler* masm, DecoratorSet decorators, bool is_oop,
+ Register start, Register end, Register scratch, RegSet saved_regs) {
+ if (is_oop) {
+ __ push(saved_regs, sp);
+ // must compute element count unless barrier set interface is changed (other platforms supply count)
+ assert_different_registers(start, end, scratch);
+ __ lea(scratch, Address(end, BytesPerHeapOop));
+ __ sub(scratch, scratch, start); // subtract start to get #bytes
+ __ lsr(scratch, scratch, LogBytesPerHeapOop); // convert to element count
+ __ mov(c_rarg0, start);
+ __ mov(c_rarg1, scratch);
+ __ call_VM_leaf(CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_ref_array_post_entry), 2);
+ __ pop(saved_regs, sp);
+ }
+}
+
+void ShenandoahBarrierSetAssembler::shenandoah_write_barrier_pre(MacroAssembler* masm,
+ Register obj,
+ Register pre_val,
+ Register thread,
+ Register tmp,
+ bool tosca_live,
+ bool expand_call) {
+ if (ShenandoahSATBBarrier) {
+ satb_write_barrier_pre(masm, obj, pre_val, thread, tmp, tosca_live, expand_call);
+ }
+}
+
+void ShenandoahBarrierSetAssembler::satb_write_barrier_pre(MacroAssembler* masm,
+ Register obj,
+ Register pre_val,
+ Register thread,
+ Register tmp,
+ bool tosca_live,
+ bool expand_call) {
+ // If expand_call is true then we expand the call_VM_leaf macro
+ // directly to skip generating the check by
+ // InterpreterMacroAssembler::call_VM_leaf_base that checks _last_sp.
+
+ assert(thread == rthread, "must be");
+
+ Label done;
+ Label runtime;
+
+ assert_different_registers(obj, pre_val, tmp, rscratch1);
+ assert(pre_val != noreg && tmp != noreg, "expecting a register");
+
+ Address in_progress(thread, in_bytes(ShenandoahThreadLocalData::satb_mark_queue_active_offset()));
+ Address index(thread, in_bytes(ShenandoahThreadLocalData::satb_mark_queue_index_offset()));
+ Address buffer(thread, in_bytes(ShenandoahThreadLocalData::satb_mark_queue_buffer_offset()));
+
+ // Is marking active?
+ if (in_bytes(SATBMarkQueue::byte_width_of_active()) == 4) {
+ __ ldrw(tmp, in_progress);
+ } else {
+ assert(in_bytes(SATBMarkQueue::byte_width_of_active()) == 1, "Assumption");
+ __ ldrb(tmp, in_progress);
+ }
+ __ cbzw(tmp, done);
+
+ // Do we need to load the previous value?
+ if (obj != noreg) {
+ __ load_heap_oop(pre_val, Address(obj, 0), noreg, noreg, AS_RAW);
+ }
+
+ // Is the previous value null?
+ __ cbz(pre_val, done);
+
+ // Can we store original value in the thread's buffer?
+ // Is index == 0?
+ // (The index field is typed as size_t.)
+
+ __ ldr(tmp, index); // tmp := *index_adr
+ __ cbz(tmp, runtime); // tmp == 0?
+ // If yes, goto runtime
+
+ __ sub(tmp, tmp, wordSize); // tmp := tmp - wordSize
+ __ str(tmp, index); // *index_adr := tmp
+ __ ldr(rscratch1, buffer);
+ __ add(tmp, tmp, rscratch1); // tmp := tmp + *buffer_adr
+
+ // Record the previous value
+ __ str(pre_val, Address(tmp, 0));
+ __ b(done);
+
+ __ bind(runtime);
+ // save the live input values
+ RegSet saved = RegSet::of(pre_val);
+ if (tosca_live) saved += RegSet::of(r0);
+ if (obj != noreg) saved += RegSet::of(obj);
+
+ __ push(saved, sp);
+
+ // Calling the runtime using the regular call_VM_leaf mechanism generates
+ // code (generated by InterpreterMacroAssember::call_VM_leaf_base)
+ // that checks that the *(rfp+frame::interpreter_frame_last_sp) == NULL.
+ //
+ // If we care generating the pre-barrier without a frame (e.g. in the
+ // intrinsified Reference.get() routine) then ebp might be pointing to
+ // the caller frame and so this check will most likely fail at runtime.
+ //
+ // Expanding the call directly bypasses the generation of the check.
+ // So when we do not have have a full interpreter frame on the stack
+ // expand_call should be passed true.
+
+ if (expand_call) {
+ assert(pre_val != c_rarg1, "smashed arg");
+ __ super_call_VM_leaf(CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_ref_field_pre_entry), pre_val, thread);
+ } else {
+ __ call_VM_leaf(CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_ref_field_pre_entry), pre_val, thread);
+ }
+
+ __ pop(saved, sp);
+
+ __ bind(done);
+}
+
+void ShenandoahBarrierSetAssembler::read_barrier(MacroAssembler* masm, Register dst) {
+ if (ShenandoahReadBarrier) {
+ read_barrier_impl(masm, dst);
+ }
+}
+
+void ShenandoahBarrierSetAssembler::read_barrier_impl(MacroAssembler* masm, Register dst) {
+ assert(UseShenandoahGC && (ShenandoahReadBarrier || ShenandoahStoreValReadBarrier || ShenandoahCASBarrier), "should be enabled");
+ Label is_null;
+ __ cbz(dst, is_null);
+ read_barrier_not_null_impl(masm, dst);
+ __ bind(is_null);
+}
+
+void ShenandoahBarrierSetAssembler::read_barrier_not_null(MacroAssembler* masm, Register dst) {
+ if (ShenandoahReadBarrier) {
+ read_barrier_not_null_impl(masm, dst);
+ }
+}
+
+
+void ShenandoahBarrierSetAssembler::read_barrier_not_null_impl(MacroAssembler* masm, Register dst) {
+ assert(UseShenandoahGC && (ShenandoahReadBarrier || ShenandoahStoreValReadBarrier || ShenandoahCASBarrier), "should be enabled");
+ __ ldr(dst, Address(dst, ShenandoahBrooksPointer::byte_offset()));
+}
+
+void ShenandoahBarrierSetAssembler::write_barrier(MacroAssembler* masm, Register dst) {
+ if (ShenandoahWriteBarrier) {
+ write_barrier_impl(masm, dst);
+ }
+}
+
+void ShenandoahBarrierSetAssembler::write_barrier_impl(MacroAssembler* masm, Register dst) {
+ assert(UseShenandoahGC && (ShenandoahWriteBarrier || ShenandoahStoreValEnqueueBarrier), "Should be enabled");
+ assert(dst != rscratch1, "need rscratch1");
+ assert(dst != rscratch2, "need rscratch2");
+
+ Label done;
+
+ Address gc_state(rthread, in_bytes(ShenandoahThreadLocalData::gc_state_offset()));
+ __ ldrb(rscratch1, gc_state);
+
+ // Check for heap stability
+ __ mov(rscratch2, ShenandoahHeap::HAS_FORWARDED | ShenandoahHeap::EVACUATION | ShenandoahHeap::TRAVERSAL);
+ __ tst(rscratch1, rscratch2);
+ __ br(Assembler::EQ, done);
+
+ // Heap is unstable, need to perform the read-barrier even if WB is inactive
+ __ ldr(dst, Address(dst, ShenandoahBrooksPointer::byte_offset()));
+
+ // Check for evacuation-in-progress and jump to WB slow-path if needed
+ __ mov(rscratch2, ShenandoahHeap::EVACUATION | ShenandoahHeap::TRAVERSAL);
+ __ tst(rscratch1, rscratch2);
+ __ br(Assembler::EQ, done);
+
+ RegSet to_save = RegSet::of(r0);
+ if (dst != r0) {
+ __ push(to_save, sp);
+ __ mov(r0, dst);
+ }
+
+ __ far_call(RuntimeAddress(CAST_FROM_FN_PTR(address, ShenandoahBarrierSetAssembler::shenandoah_wb())));
+
+ if (dst != r0) {
+ __ mov(dst, r0);
+ __ pop(to_save, sp);
+ }
+
+ __ bind(done);
+}
+
+void ShenandoahBarrierSetAssembler::storeval_barrier(MacroAssembler* masm, Register dst, Register tmp) {
+ if (ShenandoahStoreValEnqueueBarrier) {
+ Label is_null;
+ __ cbz(dst, is_null);
+ write_barrier_impl(masm, dst);
+ __ bind(is_null);
+ // Save possibly live regs.
+ RegSet live_regs = RegSet::range(r0, r4) - dst;
+ __ push(live_regs, sp);
+ __ strd(v0, __ pre(sp, 2 * -wordSize));
+
+ satb_write_barrier_pre(masm, noreg, dst, rthread, tmp, true, false);
+
+ // Restore possibly live regs.
+ __ ldrd(v0, __ post(sp, 2 * wordSize));
+ __ pop(live_regs, sp);
+ }
+ if (ShenandoahStoreValReadBarrier) {
+ read_barrier_impl(masm, dst);
+ }
+}
+
+void ShenandoahBarrierSetAssembler::load_at(MacroAssembler* masm, DecoratorSet decorators, BasicType type,
+ Register dst, Address src, Register tmp1, Register tmp_thread) {
+ bool on_oop = type == T_OBJECT || type == T_ARRAY;
+ bool in_heap = (decorators & IN_HEAP) != 0;
+ bool on_weak = (decorators & ON_WEAK_OOP_REF) != 0;
+ bool on_phantom = (decorators & ON_PHANTOM_OOP_REF) != 0;
+ bool on_reference = on_weak || on_phantom;
+
+ if (in_heap) {
+ read_barrier_not_null(masm, src.base());
+ }
+
+ BarrierSetAssembler::load_at(masm, decorators, type, dst, src, tmp1, tmp_thread);
+ if (ShenandoahKeepAliveBarrier && on_oop && on_reference) {
+ __ enter();
+ satb_write_barrier_pre(masm /* masm */,
+ noreg /* obj */,
+ dst /* pre_val */,
+ rthread /* thread */,
+ tmp1 /* tmp */,
+ true /* tosca_live */,
+ true /* expand_call */);
+ __ leave();
+ }
+}
+
+void ShenandoahBarrierSetAssembler::store_at(MacroAssembler* masm, DecoratorSet decorators, BasicType type,
+ Address dst, Register val, Register tmp1, Register tmp2) {
+ bool on_oop = type == T_OBJECT || type == T_ARRAY;
+ bool in_heap = (decorators & IN_HEAP) != 0;
+ if (in_heap) {
+ write_barrier(masm, dst.base());
+ }
+ if (!on_oop) {
+ BarrierSetAssembler::store_at(masm, decorators, type, dst, val, tmp1, tmp2);
+ return;
+ }
+
+ // flatten object address if needed
+ if (dst.index() == noreg && dst.offset() == 0) {
+ if (dst.base() != r3) {
+ __ mov(r3, dst.base());
+ }
+ } else {
+ __ lea(r3, dst);
+ }
+
+ shenandoah_write_barrier_pre(masm,
+ r3 /* obj */,
+ tmp2 /* pre_val */,
+ rthread /* thread */,
+ tmp1 /* tmp */,
+ val != noreg /* tosca_live */,
+ false /* expand_call */);
+
+ if (val == noreg) {
+ BarrierSetAssembler::store_at(masm, decorators, type, Address(r3, 0), noreg, noreg, noreg);
+ } else {
+ storeval_barrier(masm, val, tmp1);
+ // G1 barrier needs uncompressed oop for region cross check.
+ Register new_val = val;
+ if (UseCompressedOops) {
+ new_val = rscratch2;
+ __ mov(new_val, val);
+ }
+ BarrierSetAssembler::store_at(masm, decorators, type, Address(r3, 0), val, noreg, noreg);
+ }
+
+}
+
+void ShenandoahBarrierSetAssembler::obj_equals(MacroAssembler* masm, Register op1, Register op2) {
+ __ cmp(op1, op2);
+ if (ShenandoahAcmpBarrier) {
+ Label done;
+ __ br(Assembler::EQ, done);
+ // The object may have been evacuated, but we won't see it without a
+ // membar here.
+ __ membar(Assembler::LoadStore| Assembler::LoadLoad);
+ read_barrier(masm, op1);
+ read_barrier(masm, op2);
+ __ cmp(op1, op2);
+ __ bind(done);
+ }
+}
+
+void ShenandoahBarrierSetAssembler::tlab_allocate(MacroAssembler* masm, Register obj,
+ Register var_size_in_bytes,
+ int con_size_in_bytes,
+ Register t1,
+ Register t2,
+ Label& slow_case) {
+
+ assert_different_registers(obj, t2);
+ assert_different_registers(obj, var_size_in_bytes);
+ Register end = t2;
+
+ __ ldr(obj, Address(rthread, JavaThread::tlab_top_offset()));
+ if (var_size_in_bytes == noreg) {
+ __ lea(end, Address(obj, (int) (con_size_in_bytes + ShenandoahBrooksPointer::byte_size())));
+ } else {
+ __ add(var_size_in_bytes, var_size_in_bytes, ShenandoahBrooksPointer::byte_size());
+ __ lea(end, Address(obj, var_size_in_bytes));
+ }
+ __ ldr(rscratch1, Address(rthread, JavaThread::tlab_end_offset()));
+ __ cmp(end, rscratch1);
+ __ br(Assembler::HI, slow_case);
+
+ // update the tlab top pointer
+ __ str(end, Address(rthread, JavaThread::tlab_top_offset()));
+
+ __ add(obj, obj, ShenandoahBrooksPointer::byte_size());
+ __ str(obj, Address(obj, ShenandoahBrooksPointer::byte_offset()));
+
+ // recover var_size_in_bytes if necessary
+ if (var_size_in_bytes == end) {
+ __ sub(var_size_in_bytes, var_size_in_bytes, obj);
+ }
+}
+
+void ShenandoahBarrierSetAssembler::resolve(MacroAssembler* masm, DecoratorSet decorators, Register obj) {
+ bool oop_not_null = (decorators & IS_NOT_NULL) != 0;
+ bool is_write = (decorators & ACCESS_WRITE) != 0;
+ if (is_write) {
+ if (oop_not_null) {
+ write_barrier(masm, obj);
+ } else {
+ Label done;
+ __ cbz(obj, done);
+ write_barrier(masm, obj);
+ __ bind(done);
+ }
+ } else {
+ if (oop_not_null) {
+ read_barrier_not_null(masm, obj);
+ } else {
+ read_barrier(masm, obj);
+ }
+ }
+}
+
+void ShenandoahBarrierSetAssembler::cmpxchg_oop(MacroAssembler* masm, Register addr, Register expected, Register new_val,
+ bool acquire, bool release, bool weak, bool encode,
+ Register tmp1, Register tmp2, Register tmp3,
+ Register result) {
+
+ if (!ShenandoahCASBarrier) {
+ if (UseCompressedOops) {
+ if (encode) {
+ __ encode_heap_oop(tmp1, expected);
+ expected = tmp1;
+ __ encode_heap_oop(tmp3, new_val);
+ new_val = tmp3;
+ }
+ __ cmpxchg(addr, expected, new_val, Assembler::word, /* acquire*/ true, /* release*/ true, /* weak*/ false, rscratch1);
+ __ membar(__ AnyAny);
+ } else {
+ __ cmpxchg(addr, expected, new_val, Assembler::xword, /* acquire*/ true, /* release*/ true, /* weak*/ false, rscratch1);
+ __ membar(__ AnyAny);
+ }
+ return;
+ }
+
+ if (encode) {
+ storeval_barrier(masm, new_val, tmp3);
+ }
+
+ if (UseCompressedOops) {
+ if (encode) {
+ __ encode_heap_oop(tmp1, expected);
+ expected = tmp1;
+ __ encode_heap_oop(tmp2, new_val);
+ new_val = tmp2;
+ }
+ }
+ bool is_cae = (result != noreg);
+ bool is_narrow = UseCompressedOops;
+ Assembler::operand_size size = is_narrow ? Assembler::word : Assembler::xword;
+ if (! is_cae) result = rscratch1;
+
+ assert_different_registers(addr, expected, new_val, result, tmp3);
+
+ Label retry, done, fail;
+
+ // CAS, using LL/SC pair.
+ __ bind(retry);
+ __ load_exclusive(result, addr, size, acquire);
+ if (is_narrow) {
+ __ cmpw(result, expected);
+ } else {
+ __ cmp(result, expected);
+ }
+ __ br(Assembler::NE, fail);
+ __ store_exclusive(tmp3, new_val, addr, size, release);
+ if (weak) {
+ __ cmpw(tmp3, 0u); // If the store fails, return NE to our caller
+ } else {
+ __ cbnzw(tmp3, retry);
+ }
+ __ b(done);
+
+ __ bind(fail);
+ // Check if rb(expected)==rb(result)
+ // Shuffle registers so that we have memory value ready for next expected.
+ __ mov(tmp3, expected);
+ __ mov(expected, result);
+ if (is_narrow) {
+ __ decode_heap_oop(result, result);
+ __ decode_heap_oop(tmp3, tmp3);
+ }
+ read_barrier_impl(masm, result);
+ read_barrier_impl(masm, tmp3);
+ __ cmp(result, tmp3);
+ // Retry with expected now being the value we just loaded from addr.
+ __ br(Assembler::EQ, retry);
+ if (is_narrow && is_cae) {
+ // For cmp-and-exchange and narrow oops, we need to restore
+ // the compressed old-value. We moved it to 'expected' a few lines up.
+ __ mov(result, expected);
+ }
+ __ bind(done);
+
+}
+
+#ifdef COMPILER1
+
+#undef __
+#define __ ce->masm()->
+
+void ShenandoahBarrierSetAssembler::gen_pre_barrier_stub(LIR_Assembler* ce, ShenandoahPreBarrierStub* stub) {
+ ShenandoahBarrierSetC1* bs = (ShenandoahBarrierSetC1*)BarrierSet::barrier_set()->barrier_set_c1();
+ // At this point we know that marking is in progress.
+ // If do_load() is true then we have to emit the
+ // load of the previous value; otherwise it has already
+ // been loaded into _pre_val.
+
+ __ bind(*stub->entry());
+
+ assert(stub->pre_val()->is_register(), "Precondition.");
+
+ Register pre_val_reg = stub->pre_val()->as_register();
+
+ if (stub->do_load()) {
+ ce->mem2reg(stub->addr(), stub->pre_val(), T_OBJECT, stub->patch_code(), stub->info(), false /*wide*/, false /*unaligned*/);
+ }
+ __ cbz(pre_val_reg, *stub->continuation());
+ ce->store_parameter(stub->pre_val()->as_register(), 0);
+ __ far_call(RuntimeAddress(bs->pre_barrier_c1_runtime_code_blob()->code_begin()));
+ __ b(*stub->continuation());
+}
+
+void ShenandoahBarrierSetAssembler::gen_write_barrier_stub(LIR_Assembler* ce, ShenandoahWriteBarrierStub* stub) {
+
+ Register obj = stub->obj()->as_register();
+ Register res = stub->result()->as_register();
+
+ Label done;
+
+ __ bind(*stub->entry());
+
+ if (res != obj) {
+ __ mov(res, obj);
+ }
+ // Check for null.
+ if (stub->needs_null_check()) {
+ __ cbz(res, done);
+ }
+
+ write_barrier(ce->masm(), res);
+
+ __ bind(done);
+ __ b(*stub->continuation());
+}
+
+#undef __
+
+#define __ sasm->
+
+void ShenandoahBarrierSetAssembler::generate_c1_pre_barrier_runtime_stub(StubAssembler* sasm) {
+ __ prologue("shenandoah_pre_barrier", false);
+
+ // arg0 : previous value of memory
+
+ BarrierSet* bs = BarrierSet::barrier_set();
+
+ const Register pre_val = r0;
+ const Register thread = rthread;
+ const Register tmp = rscratch1;
+
+ Address queue_index(thread, in_bytes(ShenandoahThreadLocalData::satb_mark_queue_index_offset()));
+ Address buffer(thread, in_bytes(ShenandoahThreadLocalData::satb_mark_queue_buffer_offset()));
+
+ Label done;
+ Label runtime;
+
+ // Is marking still active?
+ Address gc_state(thread, in_bytes(ShenandoahThreadLocalData::gc_state_offset()));
+ __ ldrb(tmp, gc_state);
+ __ mov(rscratch2, ShenandoahHeap::MARKING | ShenandoahHeap::TRAVERSAL);
+ __ tst(tmp, rscratch2);
+ __ br(Assembler::EQ, done);
+
+ // Can we store original value in the thread's buffer?
+ __ ldr(tmp, queue_index);
+ __ cbz(tmp, runtime);
+
+ __ sub(tmp, tmp, wordSize);
+ __ str(tmp, queue_index);
+ __ ldr(rscratch2, buffer);
+ __ add(tmp, tmp, rscratch2);
+ __ load_parameter(0, rscratch2);
+ __ str(rscratch2, Address(tmp, 0));
+ __ b(done);
+
+ __ bind(runtime);
+ __ push_call_clobbered_registers();
+ __ load_parameter(0, pre_val);
+ __ call_VM_leaf(CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_ref_field_pre_entry), pre_val, thread);
+ __ pop_call_clobbered_registers();
+ __ bind(done);
+
+ __ epilogue();
+}
+
+#undef __
+
+#endif // COMPILER1
+
+address ShenandoahBarrierSetAssembler::shenandoah_wb() {
+ assert(_shenandoah_wb != NULL, "need write barrier stub");
+ return _shenandoah_wb;
+}
+
+#define __ cgen->assembler()->
+
+// Shenandoah write barrier.
+//
+// Input:
+// r0: OOP to evacuate. Not null.
+//
+// Output:
+// r0: Pointer to evacuated OOP.
+//
+// Trash rscratch1, rscratch2. Preserve everything else.
+address ShenandoahBarrierSetAssembler::generate_shenandoah_wb(StubCodeGenerator* cgen) {
+
+ __ align(6);
+ StubCodeMark mark(cgen, "StubRoutines", "shenandoah_wb");
+ address start = __ pc();
+
+ Label work;
+ __ mov(rscratch2, ShenandoahHeap::in_cset_fast_test_addr());
+ __ lsr(rscratch1, r0, ShenandoahHeapRegion::region_size_bytes_shift_jint());
+ __ ldrb(rscratch2, Address(rscratch2, rscratch1));
+ __ tbnz(rscratch2, 0, work);
+ __ ret(lr);
+ __ bind(work);
+
+ Register obj = r0;
+
+ __ enter(); // required for proper stackwalking of RuntimeStub frame
+
+ __ push_call_clobbered_registers();
+
+ __ mov(lr, CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_barrier_JRT));
+ __ blrt(lr, 1, 0, MacroAssembler::ret_type_integral);
+ __ mov(rscratch1, obj);
+ __ pop_call_clobbered_registers();
+ __ mov(obj, rscratch1);
+
+ __ leave(); // required for proper stackwalking of RuntimeStub frame
+ __ ret(lr);
+
+ return start;
+}
+
+#undef __
+
+void ShenandoahBarrierSetAssembler::barrier_stubs_init() {
+ if (ShenandoahWriteBarrier || ShenandoahStoreValEnqueueBarrier) {
+ int stub_code_size = 2048;
+ ResourceMark rm;
+ BufferBlob* bb = BufferBlob::create("shenandoah_barrier_stubs", stub_code_size);
+ CodeBuffer buf(bb);
+ StubCodeGenerator cgen(&buf);
+ _shenandoah_wb = generate_shenandoah_wb(&cgen);
+ }
+}