Improve write barriers in optimized code.

src/ia32/lithium-codegen-ia32.cc

Index: src/ia32/lithium-codegen-ia32.cc
diff --git a/src/ia32/lithium-codegen-ia32.cc b/src/ia32/lithium-codegen-ia32.cc
index f06f2420c348cc79d7de0707488c338ddabcb2eb..57190d75d8c5032e0dbce9008a5de2cd63f3da2d 100644
--- a/src/ia32/lithium-codegen-ia32.cc
+++ b/src/ia32/lithium-codegen-ia32.cc
@@ -3995,21 +3995,12 @@ void LCodeGen::DoStoreNamedField(LStoreNamedField* instr) {
   if (instr->hydrogen()->has_transition()) {
     Handle<Map> transition = instr->hydrogen()->transition_map();
     AddDeprecationDependency(transition);
-    if (!instr->hydrogen()->NeedsWriteBarrierForMap()) {
-      __ mov(FieldOperand(object, HeapObject::kMapOffset), transition);
-    } else {
+    __ mov(FieldOperand(object, HeapObject::kMapOffset), transition);
+    if (instr->hydrogen()->NeedsWriteBarrierForMap()) {
       Register temp = ToRegister(instr->temp());
       Register temp_map = ToRegister(instr->temp_map());
-      __ mov(temp_map, transition);
-      __ mov(FieldOperand(object, HeapObject::kMapOffset), temp_map);
       // Update the write barrier for the map field.
-      __ RecordWriteField(object,
-                          HeapObject::kMapOffset,
-                          temp_map,
-                          temp,
-                          kSaveFPRegs,
-                          OMIT_REMEMBERED_SET,
-                          OMIT_SMI_CHECK);
+      __ RecordWriteForMap(object, transition, temp_map, temp, kSaveFPRegs);
     }
   }
 
@@ -4050,7 +4041,8 @@ void LCodeGen::DoStoreNamedField(LStoreNamedField* instr) {
                         temp,
                         kSaveFPRegs,
                         EMIT_REMEMBERED_SET,
-                        instr->hydrogen()->SmiCheckForWriteBarrier());
+                        instr->hydrogen()->SmiCheckForWriteBarrier(),
+                        instr->hydrogen()->PointersToHereCheckForValue());
   }
 }
 
@@ -4219,7 +4211,8 @@ void LCodeGen::DoStoreKeyedFixedArray(LStoreKeyed* instr) {
                    value,
                    kSaveFPRegs,
                    EMIT_REMEMBERED_SET,
-                   check_needed);
+                   check_needed,
+                   instr->hydrogen()->PointersToHereCheckForValue());
   }
 }