Remove an unneeded temp in instance setters and indexed stores.

runtime/vm/flow_graph_compiler_x64.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/globals.h"  // Needed here to get TARGET_ARCH_X64.
 #if defined(TARGET_ARCH_X64)
 
 #include "vm/flow_graph_compiler.h"
 
 #include "vm/ast_printer.h"
@@ skipping 163 matching lines @@
 void FlowGraphCompiler::VisitNativeCall(NativeCallComp* comp) {
   Bailout("NativeCallComp");
 }
 
 
 void FlowGraphCompiler::VisitStoreIndexed(StoreIndexedComp* comp) {
   // Call operator []= but preserve the third argument value under the
   // arguments as the result of the computation.
   const String& function_name =
       String::ZoneHandle(String::NewSymbol(Token::Str(Token::kASSIGN_INDEX)));
-  // Placeholder is under value, index, and receiver.
-  const int kPlaceholderOffset = 3 * kWordSize;
-  __ movq(RAX, Address(RSP, 0));  // Value.
-  __ movq(Address(RSP, kPlaceholderOffset), RAX);
+
+  // Insert a copy of the third (last) argument under the arguments.
+  __ popq(RAX);  // Value.
+  __ popq(RBX);  // Index.
+  __ popq(RCX);  // Receiver.
+  __ pushq(RAX);
+  __ pushq(RCX);
+  __ pushq(RBX);
+  __ pushq(RAX);
   EmitInstanceCall(comp->node_id(), comp->token_index(), function_name, 3,
                    Array::ZoneHandle(), 1);
   __ popq(RAX);
 }
 
 
 void FlowGraphCompiler::VisitInstanceSetter(InstanceSetterComp* comp) {
   // Preserve the second argument under the arguments as the result of the
   // computation, then call the getter.
   const String& function_name =
       String::ZoneHandle(Field::SetterSymbol(comp->field_name()));
-  // Placeholder is under value and receiver.
-  const int kPlaceholderOffset = 2 * kWordSize;
-  __ movq(RAX, Address(RSP, 0));  // Value.
-  __ movq(Address(RSP, kPlaceholderOffset), RAX);
+
+  // Insert a copy of the second (last) argument under the arguments.
+  __ popq(RAX);  // Value.
+  __ popq(RBX);  // Reciever.
+  __ pushq(RAX);
+  __ pushq(RBX);
+  __ pushq(RAX);
   EmitInstanceCall(comp->node_id(), comp->token_index(), function_name, 2,
                    Array::ZoneHandle(), 1);
   __ popq(RAX);
 }
 
 
 void FlowGraphCompiler::VisitJoinEntry(JoinEntryInstr* instr) {
   Bailout("JoinEntryInstr");
 }
 
@@ skipping 199 matching lines @@
 void FlowGraphCompiler::FinalizeExceptionHandlers(const Code& code) {
   // We don't compile exception handlers yet.
   code.set_exception_handlers(
       ExceptionHandlers::Handle(ExceptionHandlers::New(0)));
 }
 
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_X64