Refactor transitioning stores.

src/arm64/lithium-codegen-arm64.cc

Index: src/arm64/lithium-codegen-arm64.cc
diff --git a/src/arm64/lithium-codegen-arm64.cc b/src/arm64/lithium-codegen-arm64.cc
index dab60e572ed9e5c541128c51a57bbb318efd6b6a..462c20ffd03a9bedb6b91f1409cace17a90ce570 100644
--- a/src/arm64/lithium-codegen-arm64.cc
+++ b/src/arm64/lithium-codegen-arm64.cc
@@ -5302,14 +5302,12 @@ void LCodeGen::DoStoreNamedField(LStoreNamedField* instr) {
   int offset = access.offset();
 
   if (access.IsExternalMemory()) {
-    ASSERT(!instr->hydrogen()->has_transition());
     ASSERT(!instr->hydrogen()->NeedsWriteBarrier());
     Register value = ToRegister(instr->value());
     __ Store(value, MemOperand(object, offset), representation);
     return;
   } else if (representation.IsDouble()) {
     ASSERT(access.IsInobject());
-    ASSERT(!instr->hydrogen()->has_transition());
     ASSERT(!instr->hydrogen()->NeedsWriteBarrier());
     FPRegister value = ToDoubleRegister(instr->value());
     __ Str(value, FieldMemOperand(object, offset));
@@ -5332,26 +5330,6 @@ void LCodeGen::DoStoreNamedField(LStoreNamedField* instr) {
     check_needed = OMIT_SMI_CHECK;
   }
 
-  if (instr->hydrogen()->has_transition()) {
-    Handle<Map> transition = instr->hydrogen()->transition_map();
-    AddDeprecationDependency(transition);
-    // Store the new map value.
-    Register new_map_value = ToRegister(instr->temp0());
-    __ Mov(new_map_value, Operand(transition));
-    __ Str(new_map_value, FieldMemOperand(object, HeapObject::kMapOffset));
-    if (instr->hydrogen()->NeedsWriteBarrierForMap()) {
-      // Update the write barrier for the map field.
-      __ RecordWriteField(object,
-                          HeapObject::kMapOffset,
-                          new_map_value,
-                          ToRegister(instr->temp1()),
-                          GetLinkRegisterState(),
-                          kSaveFPRegs,
-                          OMIT_REMEMBERED_SET,
-                          OMIT_SMI_CHECK);
-    }
-  }
-
   // Do the store.
   Register destination;
   if (access.IsInobject()) {