Do inline object filtering (via page flags) before call to RecordWriteStub.

src/ia32/code-stubs-ia32.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 5970 matching lines @@
 // 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) {
   NearLabel skip_non_incremental_part;
   __ jmp(&skip_non_incremental_part);
   if (!HEAP->incremental_marking()->IsMarking()) {
     ASSERT(masm->get_opcode(-2) == kSkipNonIncrementalPartInstruction);
     masm->set_opcode(-2, kTwoByteNopInstruction);
   }
 
-  if (FLAG_debug_code) {
-    NearLabel ok;
-    __ cmp(value_, Operand(address_, 0));
-    __ j(equal, &ok);
-    __ Abort("Registers did not match in write barrier");
-    __ bind(&ok);
-  }
-
   if (emit_remembered_set_ == EMIT_REMEMBERED_SET) {
     NearLabel skip;
-    __ HasScanOnScavenge(object_, value_, &skip);
     __ RememberedSetHelper(address_, value_, save_fp_regs_mode_);
     __ bind(&skip);
   }
   __ ret(0);
 
   __ bind(&skip_non_incremental_part);
-
+  __ mov(value_, Operand(address_, 0));
   GenerateIncremental(masm);
 }
 
 
 void RecordWriteStub::GenerateIncremental(MacroAssembler* masm) {
   regs_.Save(masm);
 
   Label value_in_old_space;
 
   __ InNewSpace(value_, regs_.scratch0(), not_equal, &value_in_old_space);
@@ skipping 34 matching lines @@
   Label both_in_new_space;
   Label value_in_new_space_object_is_black_no_remembered_set;
 
   // The value is in new space.  Check the object.
   __ InNewSpace(regs_.object(), regs_.scratch0(), equal, &both_in_new_space);
 
   // Value is in new space, object is in old space.  Could we be lucky and find
   // the scan_on_scavenge flag on the object's page?
   if (emit_remembered_set_ == EMIT_REMEMBERED_SET) {
     Label scan_on_scavenge;
-    __ HasScanOnScavenge(regs_.object(), regs_.scratch0(), &scan_on_scavenge);
+    __ CheckPageFlag(regs_.object(),
+                     regs_.scratch0(),
+                     MemoryChunk::SCAN_ON_SCAVENGE,
+                     not_zero,
+                     &scan_on_scavenge);
     GenerateIncrementalValueIsInNewSpaceObjectIsInOldSpaceRememberedSet(masm);
     __ bind(&scan_on_scavenge);
   }
   // This function will also bind the label.
   GenerateIncrementalValueIsInNewSpaceObjectIsInOldSpaceNoRememberedSet(
       masm, &value_in_new_space_object_is_black_no_remembered_set);
 
   __ bind(&both_in_new_space);
   __ InNewSpaceIsBlack(regs_.object(),
                        regs_.scratch0(),
@@ skipping 143 matching lines @@
   regs_.Restore(masm);
   __ ret(0);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32