Combine the incremental-marking write barrier and the remembered-set...

src/ia32/codegen-ia32.cc

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 //
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@@ skipping 7813 matching lines @@
   __ mov(object.reg(), Operand(index1.reg(), 0));
   __ mov(tmp2.reg(),   Operand(index2.reg(), 0));
   __ mov(Operand(index2.reg(), 0), object.reg());
   __ mov(Operand(index1.reg(), 0), tmp2.reg());
 
   Label done;
   __ InNewSpace(tmp1.reg(), tmp2.reg(), equal, &done);
   // Possible optimization: do a check that both values are Smis
   // (or them and test against Smi mask.)
 
+  // Since we are swapping two objects, the incremental marker is not disturbed,
+  // so we don't call the stub that handles this.  TODO(gc): Optimize by
+  // checking the scan_on_scavenge flag, probably by calling the stub.
   __ mov(tmp2.reg(), tmp1.reg());
-  __ RecordWriteHelper(tmp2.reg(), index1.reg(), object.reg(), kDontSaveFPRegs);
-  __ RecordWriteHelper(tmp1.reg(), index2.reg(), object.reg(), kDontSaveFPRegs);
+  __ RememberedSetHelper(tmp2.reg(),
+                         index1.reg(),
+                         object.reg(),
+                         kDontSaveFPRegs);
+  __ RememberedSetHelper(tmp1.reg(),
+                         index2.reg(),
+                         object.reg(),
+                         kDontSaveFPRegs);
   __ bind(&done);
 
   deferred->BindExit();
   frame_->Push(Factory::undefined_value());
 }
 
 
 void CodeGenerator::GenerateCallFunction(ZoneList<Expression*>* args) {
   Comment cmnt(masm_, "[ GenerateCallFunction");
 
@@ skipping 1932 matching lines @@
       ASSERT(receiver.is_valid());
       __ mov(receiver.reg(), Operand(value.reg()));
     }
 
     // Update the write barrier. To save instructions in the inlined
     // version we do not filter smis.
     Label skip_write_barrier;
     __ InNewSpace(receiver.reg(), value.reg(), equal, &skip_write_barrier);
     int delta_to_record_write = masm_->SizeOfCodeGeneratedSince(&patch_site);
     __ lea(scratch.reg(), Operand(receiver.reg(), offset));
-    __ RecordWriteHelper(receiver.reg(),
-                         scratch.reg(),
-                         value.reg(),
-                         kDontSaveFPRegs);
+    __ RememberedSetHelper(receiver.reg(),

[Vyacheslav Egorov (Chromium), 2011/04/06 11:46:40]

this place should have an incremental write barrier. why did you remove it?

[Erik Corry, 2011/04/06 12:31:28]

This whole file is on death row.  Comment added.  You will note that I did not
remove it in this change.

+                           scratch.reg(),
+                           value.reg(),
+                           kDontSaveFPRegs);
     if (FLAG_debug_code) {
       __ mov(receiver.reg(), Immediate(BitCast<int32_t>(kZapValue)));
       __ mov(value.reg(), Immediate(BitCast<int32_t>(kZapValue)));
       __ mov(scratch.reg(), Immediate(BitCast<int32_t>(kZapValue)));
     }
     __ bind(&skip_write_barrier);
     value.Unuse();
     scratch.Unuse();
     receiver.Unuse();
     done.Jump(&result);
@@ skipping 574 matching lines @@
   memcpy(base, desc.buffer, desc.instr_size);
   CPU::FlushICache(base, desc.instr_size);
   return FUNCTION_CAST<MemCopyFunction>(reinterpret_cast<Address>(base));
 }
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32