Patch RecordWriteStub after adding it to the stub cache not during generation.

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 5164 matching lines @@
   } else {
     __ ret(0);
   }
 
   __ bind(&skip_to_incremental_noncompacting);
   GenerateIncremental(masm, INCREMENTAL);
 
   __ bind(&skip_to_incremental_compacting);
   GenerateIncremental(masm, INCREMENTAL_COMPACTION);
 
-  // TODO(1545) ensure that GC can't happen after stub was generated by before
-  // it was added to a stub cache.
-  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);
-  }
+  // Initial mode of the stub is expected to be STORE_BUFFER_ONLY.
+  // Will be checked in IncrementalMarking::ActivateGeneratedStub.
+  masm->set_byte_at(0, kTwoByteNopInstruction);
+  masm->set_byte_at(2, kFiveByteNopInstruction);
 }
 
 
 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));
@@ skipping 99 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