src/hotspot/share/runtime/stackValue.cpp
changeset 47216 71c04702a3d5
parent 46271 979ebd346ecf
child 47816 ac0af7750da9
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/runtime/stackValue.cpp	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,211 @@
+/*
+ * Copyright (c) 1997, 2017, 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 "code/debugInfo.hpp"
+#include "oops/oop.inline.hpp"
+#include "runtime/frame.inline.hpp"
+#include "runtime/handles.inline.hpp"
+#include "runtime/stackValue.hpp"
+
+StackValue* StackValue::create_stack_value(const frame* fr, const RegisterMap* reg_map, ScopeValue* sv) {
+  if (sv->is_location()) {
+    // Stack or register value
+    Location loc = ((LocationValue *)sv)->location();
+
+#ifdef SPARC
+    // %%%%% Callee-save floats will NOT be working on a Sparc until we
+    // handle the case of a 2 floats in a single double register.
+    assert( !(loc.is_register() && loc.type() == Location::float_in_dbl), "Sparc does not handle callee-save floats yet" );
+#endif // SPARC
+
+    // First find address of value
+
+    address value_addr = loc.is_register()
+      // Value was in a callee-save register
+      ? reg_map->location(VMRegImpl::as_VMReg(loc.register_number()))
+      // Else value was directly saved on the stack. The frame's original stack pointer,
+      // before any extension by its callee (due to Compiler1 linkage on SPARC), must be used.
+      : ((address)fr->unextended_sp()) + loc.stack_offset();
+
+    // Then package it right depending on type
+    // Note: the transfer of the data is thru a union that contains
+    // an intptr_t. This is because an interpreter stack slot is
+    // really an intptr_t. The use of a union containing an intptr_t
+    // ensures that on a 64 bit platform we have proper alignment
+    // and that we store the value where the interpreter will expect
+    // to find it (i.e. proper endian). Similarly on a 32bit platform
+    // using the intptr_t ensures that when a value is larger than
+    // a stack slot (jlong/jdouble) that we capture the proper part
+    // of the value for the stack slot in question.
+    //
+    switch( loc.type() ) {
+    case Location::float_in_dbl: { // Holds a float in a double register?
+      // The callee has no clue whether the register holds a float,
+      // double or is unused.  He always saves a double.  Here we know
+      // a double was saved, but we only want a float back.  Narrow the
+      // saved double to the float that the JVM wants.
+      assert( loc.is_register(), "floats always saved to stack in 1 word" );
+      union { intptr_t p; jfloat jf; } value;
+      value.p = (intptr_t) CONST64(0xDEADDEAFDEADDEAF);
+      value.jf = (jfloat) *(jdouble*) value_addr;
+      return new StackValue(value.p); // 64-bit high half is stack junk
+    }
+    case Location::int_in_long: { // Holds an int in a long register?
+      // The callee has no clue whether the register holds an int,
+      // long or is unused.  He always saves a long.  Here we know
+      // a long was saved, but we only want an int back.  Narrow the
+      // saved long to the int that the JVM wants.
+      assert( loc.is_register(), "ints always saved to stack in 1 word" );
+      union { intptr_t p; jint ji;} value;
+      value.p = (intptr_t) CONST64(0xDEADDEAFDEADDEAF);
+      value.ji = (jint) *(jlong*) value_addr;
+      return new StackValue(value.p); // 64-bit high half is stack junk
+    }
+#ifdef _LP64
+    case Location::dbl:
+      // Double value in an aligned adjacent pair
+      return new StackValue(*(intptr_t*)value_addr);
+    case Location::lng:
+      // Long   value in an aligned adjacent pair
+      return new StackValue(*(intptr_t*)value_addr);
+    case Location::narrowoop: {
+      union { intptr_t p; narrowOop noop;} value;
+      value.p = (intptr_t) CONST64(0xDEADDEAFDEADDEAF);
+      if (loc.is_register()) {
+        // The callee has no clue whether the register holds an int,
+        // long or is unused.  He always saves a long.  Here we know
+        // a long was saved, but we only want an int back.  Narrow the
+        // saved long to the int that the JVM wants.
+        value.noop =  (narrowOop) *(julong*) value_addr;
+      } else {
+        value.noop = *(narrowOop*) value_addr;
+      }
+      // Decode narrowoop and wrap a handle around the oop
+      Handle h(Thread::current(), oopDesc::decode_heap_oop(value.noop));
+      return new StackValue(h);
+    }
+#endif
+    case Location::oop: {
+      oop val = *(oop *)value_addr;
+#ifdef _LP64
+      if (Universe::is_narrow_oop_base(val)) {
+         // Compiled code may produce decoded oop = narrow_oop_base
+         // when a narrow oop implicit null check is used.
+         // The narrow_oop_base could be NULL or be the address
+         // of the page below heap. Use NULL value for both cases.
+         val = (oop)NULL;
+      }
+#endif
+      Handle h(Thread::current(), val); // Wrap a handle around the oop
+      return new StackValue(h);
+    }
+    case Location::addr: {
+      ShouldNotReachHere(); // both C1 and C2 now inline jsrs
+    }
+    case Location::normal: {
+      // Just copy all other bits straight through
+      union { intptr_t p; jint ji;} value;
+      value.p = (intptr_t) CONST64(0xDEADDEAFDEADDEAF);
+      value.ji = *(jint*)value_addr;
+      return new StackValue(value.p);
+    }
+    case Location::invalid:
+      return new StackValue();
+    default:
+      ShouldNotReachHere();
+    }
+
+  } else if (sv->is_constant_int()) {
+    // Constant int: treat same as register int.
+    union { intptr_t p; jint ji;} value;
+    value.p = (intptr_t) CONST64(0xDEADDEAFDEADDEAF);
+    value.ji = (jint)((ConstantIntValue*)sv)->value();
+    return new StackValue(value.p);
+  } else if (sv->is_constant_oop()) {
+    // constant oop
+    return new StackValue(sv->as_ConstantOopReadValue()->value());
+#ifdef _LP64
+  } else if (sv->is_constant_double()) {
+    // Constant double in a single stack slot
+    union { intptr_t p; double d; } value;
+    value.p = (intptr_t) CONST64(0xDEADDEAFDEADDEAF);
+    value.d = ((ConstantDoubleValue *)sv)->value();
+    return new StackValue(value.p);
+  } else if (sv->is_constant_long()) {
+    // Constant long in a single stack slot
+    union { intptr_t p; jlong jl; } value;
+    value.p = (intptr_t) CONST64(0xDEADDEAFDEADDEAF);
+    value.jl = ((ConstantLongValue *)sv)->value();
+    return new StackValue(value.p);
+#endif
+  } else if (sv->is_object()) { // Scalar replaced object in compiled frame
+    Handle ov = ((ObjectValue *)sv)->value();
+    return new StackValue(ov, (ov.is_null()) ? 1 : 0);
+  }
+
+  // Unknown ScopeValue type
+  ShouldNotReachHere();
+  return new StackValue((intptr_t) 0);   // dummy
+}
+
+
+BasicLock* StackValue::resolve_monitor_lock(const frame* fr, Location location) {
+  assert(location.is_stack(), "for now we only look at the stack");
+  int word_offset = location.stack_offset() / wordSize;
+  // (stack picture)
+  // high: [     ]  word_offset + 1
+  // low   [     ]  word_offset
+  //
+  // sp->  [     ]  0
+  // the word_offset is the distance from the stack pointer to the lowest address
+  // The frame's original stack pointer, before any extension by its callee
+  // (due to Compiler1 linkage on SPARC), must be used.
+  return (BasicLock*) (fr->unextended_sp() + word_offset);
+}
+
+
+#ifndef PRODUCT
+
+void StackValue::print_on(outputStream* st) const {
+  switch(_type) {
+    case T_INT:
+      st->print("%d (int) %f (float) %x (hex)",  *(int *)&_i, *(float *)&_i,  *(int *)&_i);
+      break;
+
+    case T_OBJECT:
+     _o()->print_value_on(st);
+      st->print(" <" INTPTR_FORMAT ">", p2i((address)_o()));
+     break;
+
+    case T_CONFLICT:
+     st->print("conflict");
+     break;
+
+    default:
+     ShouldNotReachHere();
+  }
+}
+
+#endif