Omit smi-check for write-barrier unless tagged.

src/x64/stub-cache-x64.cc

Index: src/x64/stub-cache-x64.cc
diff --git a/src/x64/stub-cache-x64.cc b/src/x64/stub-cache-x64.cc
index 148f65ee0d51e49379f8d2e8b795bc759131a727..f6c81b4c8ca298084c84b8e2116b2f375d947002 100644
--- a/src/x64/stub-cache-x64.cc
+++ b/src/x64/stub-cache-x64.cc
@@ -880,6 +880,8 @@ void StubCompiler::GenerateStoreTransition(MacroAssembler* masm,
   index -= object->map()->inobject_properties();
 
   // TODO(verwaest): Share this code as a code stub.
+  SmiCheck smi_check = representation.IsTagged()
+      ? INLINE_SMI_CHECK : OMIT_SMI_CHECK;
   if (index < 0) {
     // Set the property straight into the object.
     int offset = object->map()->instance_size() + (index * kPointerSize);
@@ -898,7 +900,8 @@ void StubCompiler::GenerateStoreTransition(MacroAssembler* masm,
         ASSERT(storage_reg.is(name_reg));
       }
       __ RecordWriteField(
-          receiver_reg, offset, name_reg, scratch1, kDontSaveFPRegs);
+          receiver_reg, offset, name_reg, scratch1, kDontSaveFPRegs,
+          EMIT_REMEMBERED_SET, smi_check);
     }
   } else {
     // Write to the properties array.
@@ -920,7 +923,8 @@ void StubCompiler::GenerateStoreTransition(MacroAssembler* masm,
         ASSERT(storage_reg.is(name_reg));
       }
       __ RecordWriteField(
-          scratch1, offset, name_reg, receiver_reg, kDontSaveFPRegs);
+          scratch1, offset, name_reg, receiver_reg, kDontSaveFPRegs,
+          EMIT_REMEMBERED_SET, smi_check);
     }
   }
 
@@ -1000,6 +1004,8 @@ void StubCompiler::GenerateStoreField(MacroAssembler* masm,
   }
 
   // TODO(verwaest): Share this code as a code stub.
+  SmiCheck smi_check = representation.IsTagged()
+      ? INLINE_SMI_CHECK : OMIT_SMI_CHECK;
   if (index < 0) {
     // Set the property straight into the object.
     int offset = object->map()->instance_size() + (index * kPointerSize);
@@ -1010,7 +1016,8 @@ void StubCompiler::GenerateStoreField(MacroAssembler* masm,
       // Pass the value being stored in the now unused name_reg.
       __ movq(name_reg, value_reg);
       __ RecordWriteField(
-          receiver_reg, offset, name_reg, scratch1, kDontSaveFPRegs);
+          receiver_reg, offset, name_reg, scratch1, kDontSaveFPRegs,
+          EMIT_REMEMBERED_SET, smi_check);
     }
   } else {
     // Write to the properties array.
@@ -1024,7 +1031,8 @@ void StubCompiler::GenerateStoreField(MacroAssembler* masm,
       // Pass the value being stored in the now unused name_reg.
       __ movq(name_reg, value_reg);
       __ RecordWriteField(
-          scratch1, offset, name_reg, receiver_reg, kDontSaveFPRegs);
+          scratch1, offset, name_reg, receiver_reg, kDontSaveFPRegs,
+          EMIT_REMEMBERED_SET, smi_check);
     }
   }