Fix compilation on ARM and x64.

src/x64/code-stubs-x64.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 5140 matching lines @@
   __ Drop(1);
   __ ret(2 * kPointerSize);
 }
 
 
 // Takes the input in 3 registers: address_ value_ and object_.  A pointer to
 // the value has just been written into the object, now this stub makes sure
 // we keep the GC informed.  The word in the object where the value has been
 // written is in the address register.
 void RecordWriteStub::Generate(MacroAssembler* masm) {
-  Label skip_non_incremental_part;
+  Label skip_to_incremental_noncompacting;
+  Label skip_to_incremental_compacting;
 
   // The first instruction is generated as a label so as to get the offset
   // fixed up correctly by the bind(Label*) call.  We patch it back and forth
   // between a 2-byte compare instruction (a nop in this position) and the real
   // branch when we start and stop incremental heap marking.

[Erik Corry, 2011/07/08 09:06:49]

This comment does not mention compaction.  I would suggest 'generated with a
label' rather than 'generated as a label'

-  __ jmp(&skip_non_incremental_part, Label::kNear);
-  if (!masm->isolate()->heap()->incremental_marking()->IsMarking()) {
-    ASSERT(masm->byte_at(masm->pc_offset() - 2) ==
-           kSkipNonIncrementalPartInstruction);
-    masm->set_byte_at(masm->pc_offset() - 2, kTwoByteNopInstruction);
-  }
+  __ jmp(&skip_to_incremental_noncompacting, Label::kNear);
+  __ jmp(&skip_to_incremental_compacting, Label::kFar);
 
   if (remembered_set_action_ == EMIT_REMEMBERED_SET) {
     __ RememberedSetHelper(
         address_, value_, save_fp_regs_mode_, MacroAssembler::kReturnAtEnd);
   } else {
     __ ret(0);
   }
 
-  __ bind(&skip_non_incremental_part);
-  GenerateIncremental(masm);
+  __ bind(&skip_to_incremental_noncompacting);
+  GenerateIncremental(masm, INCREMENTAL);
+
+  __ bind(&skip_to_incremental_compacting);
+  GenerateIncremental(masm, INCREMENTAL_COMPACTION);
+
+  // TODO(gc) ensure that GC can't happen after stub was generated by before
+  // it was added to a stub cache.

[Erik Corry, 2011/07/08 09:06:49]

This looks nasty.  Please file a bug and put the bug number in here.  One way
may be to patch again just after it is added to the stub.

+  IncrementalMarking* marking = masm->isolate()->heap()->incremental_marking();
+  if (!marking->IsMarking() || marking->IsCompacting()) {
+    ASSERT(masm->byte_at(0) == kTwoByteJumpInstruction);
+    masm->set_byte_at(0, kTwoByteNopInstruction);
+  }
+
+  if (!marking->IsMarking()) {
+    ASSERT(masm->byte_at(2) == kFiveByteJumpInstruction);
+    masm->set_byte_at(2, kFiveByteNopInstruction);
+  }
 }
 
 
-void RecordWriteStub::GenerateIncremental(MacroAssembler* masm) {
+void RecordWriteStub::GenerateIncremental(MacroAssembler* masm, Mode mode) {
   regs_.Save(masm);
 
   if (remembered_set_action_ == EMIT_REMEMBERED_SET) {
     Label dont_need_remembered_set;
 
     __ movq(regs_.scratch0(), Operand(regs_.address(), 0));
     __ JumpIfNotInNewSpace(regs_.scratch0(),
                            regs_.scratch0(),
                            &dont_need_remembered_set);
 
     __ CheckPageFlag(regs_.object(),
                      regs_.scratch0(),
                      MemoryChunk::SCAN_ON_SCAVENGE,
                      not_zero,
                      &dont_need_remembered_set);
 
     // First notify the incremental marker if necessary, then update the
     // remembered set.
     CheckNeedsToInformIncrementalMarker(
-        masm, kUpdateRememberedSetOnNoNeedToInformIncrementalMarker);
-    InformIncrementalMarker(masm);
+        masm, kUpdateRememberedSetOnNoNeedToInformIncrementalMarker, mode);
+    InformIncrementalMarker(masm, mode);
     regs_.Restore(masm);
     __ RememberedSetHelper(
         address_, value_, save_fp_regs_mode_, MacroAssembler::kReturnAtEnd);
 
     __ bind(&dont_need_remembered_set);
   }
 
   CheckNeedsToInformIncrementalMarker(
-      masm, kReturnOnNoNeedToInformIncrementalMarker);
-  InformIncrementalMarker(masm);
+      masm, kReturnOnNoNeedToInformIncrementalMarker, mode);
+  InformIncrementalMarker(masm, mode);
   regs_.Restore(masm);
   __ ret(0);
 }
 
 
-void RecordWriteStub::InformIncrementalMarker(MacroAssembler* masm) {
+void RecordWriteStub::InformIncrementalMarker(MacroAssembler* masm, Mode mode) {
   regs_.SaveCallerSaveRegisters(masm, save_fp_regs_mode_);
 #ifdef _WIN64
   Register arg3 = r8;
   Register arg2 = rdx;
   Register arg1 = rcx;
 #else
   Register arg3 = rdx;
   Register arg2 = rsi;
   Register arg1 = rdi;
 #endif
-  bool save_address = arg1.is(regs_.address());
-  if (save_address) {
-    __ movq(arg3, regs_.address());
-  }
+  Register address =
+      arg1.is(regs_.address()) ? kScratchRegister : regs_.address();
+  ASSERT(!address.is(regs_.object()));
+  ASSERT(!address.is(arg1));
+  __ Move(address, regs_.address());
   __ Move(arg1, regs_.object());
-  if (save_address) {
-    __ movq(arg2, Operand(arg3, 0));
+  if (mode == INCREMENTAL_COMPACTION) {
+    // TODO(gc) Can we just set address arg2 in the beginning?
+    __ Move(arg2, address);
   } else {
-    __ movq(arg2, Operand(regs_.address(), 0));
+    ASSERT(mode == INCREMENTAL);
+    __ movq(arg2, Operand(address, 0));
   }
   __ LoadAddress(arg3, ExternalReference::isolate_address());
   // TODO(gc): Create a fast version of this C function that does not duplicate
   // the checks done in the stub.
   int argument_count = 3;
   __ PrepareCallCFunction(argument_count);
-  __ CallCFunction(
-      ExternalReference::incremental_marking_record_write_function(
-          masm->isolate()),
-      argument_count);
+  if (mode == INCREMENTAL_COMPACTION) {
+    __ CallCFunction(
+        ExternalReference::incremental_evacuation_record_write_function(
+            masm->isolate()),
+        argument_count);
+  } else {
+    ASSERT(mode == INCREMENTAL);
+    __ CallCFunction(
+        ExternalReference::incremental_marking_record_write_function(
+            masm->isolate()),
+        argument_count);
+  }
   regs_.RestoreCallerSaveRegisters(masm, save_fp_regs_mode_);
 }
 
 
 void RecordWriteStub::CheckNeedsToInformIncrementalMarker(
     MacroAssembler* masm,
-    RecordWriteStub::OnNoNeedToInformIncrementalMarker on_no_need) {
+    OnNoNeedToInformIncrementalMarker on_no_need,
+    Mode mode) {
   Label on_black;
 
   // Let's look at the color of the object:  If it is not black we don't have
   // to inform the incremental marker.
   __ JumpIfBlack(regs_.object(),
                  regs_.scratch0(),
                  regs_.scratch1(),
                  &on_black,
                  Label::kNear);
 
@@ skipping 10 matching lines @@
   // TODO(gc): Add call to EnsureNotWhite here.
   // Fall through when we need to inform the incremental marker.
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64