Remove an unneeded temp in instance setters and indexed stores.

runtime/vm/flow_graph_builder.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/flow_graph_builder.h"
 
 #include "vm/flags.h"
 #include "vm/intermediate_language.h"
 #include "vm/longjump.h"
 #include "vm/os.h"
@@ skipping 453 matching lines @@
   arguments->Add(for_receiver.value());
   const String& name =
       String::ZoneHandle(Field::GetterSymbol(node->field_name()));
   InstanceCallComp* call =
       new InstanceCallComp(node, name, arguments, Array::ZoneHandle(), 1);
   ReturnComputation(call);
 }
 
 
 void EffectGraphVisitor::VisitInstanceSetterNode(InstanceSetterNode* node) {
-  // We preallocate a temporary to overlap with the value of the assignment.
-  const Smi& zero = Smi::ZoneHandle(Smi::New(0));
-  AddInstruction(new BindInstr(temp_index(), new ConstantVal(zero)));
-  TempVal* placeholder = new TempVal(temp_index());
-  ArgumentGraphVisitor for_receiver(owner(), temp_index() + 1);
+  ArgumentGraphVisitor for_receiver(owner(), temp_index());
   node->receiver()->Visit(&for_receiver);
   Append(for_receiver);
   ArgumentGraphVisitor for_value(owner(), for_receiver.temp_index());
   node->value()->Visit(&for_value);
   Append(for_value);
   InstanceSetterComp* setter = new InstanceSetterComp(node,
-                                                      placeholder,
                                                       for_receiver.value(),
                                                       for_value.value());
   ReturnComputation(setter);
 }
 
 
 void EffectGraphVisitor::VisitStaticGetterNode(StaticGetterNode* node) {
   Bailout("EffectGraphVisitor::VisitStaticGetterNode");
 }
 
@@ skipping 84 matching lines @@
   arguments->Add(for_index.value());
   const String& name =
       String::ZoneHandle(String::NewSymbol(Token::Str(Token::kINDEX)));
   InstanceCallComp* call =
       new InstanceCallComp(node, name, arguments, Array::ZoneHandle(), 1);
   ReturnComputation(call);
 }
 
 
 void EffectGraphVisitor::VisitStoreIndexedNode(StoreIndexedNode* node) {
-  // This is not a straight instance call to e0.[]=(e1, e2), it is a
-  // call to
-  //
-  // (a, i, v) { a.[]=(i, v); return v; }(e0, e1, e2)
-  //
-  // Without constructing that function, we simulate it at the IL
-  // level by preallocating a slot for the return value.
-  const Smi& zero = Smi::ZoneHandle(Smi::New(0));
-  AddInstruction(new BindInstr(temp_index(), new ConstantVal(zero)));
-  TempVal* placeholder = new TempVal(temp_index());
-  ArgumentGraphVisitor for_array(owner(), temp_index() + 1);
+  ArgumentGraphVisitor for_array(owner(), temp_index());
   node->array()->Visit(&for_array);
   Append(for_array);
   ArgumentGraphVisitor for_index(owner(), for_array.temp_index());
   node->index_expr()->Visit(&for_index);
   Append(for_index);
   ArgumentGraphVisitor for_value(owner(), for_index.temp_index());
   node->value()->Visit(&for_value);
   Append(for_value);
   StoreIndexedComp* store = new StoreIndexedComp(node,
-                                                 placeholder,
                                                  for_array.value(),
                                                  for_index.value(),
                                                  for_value.value());
   ReturnComputation(store);
 }
 
 
 // <Statement> ::= Sequence { scope: LocalScope
 //                            nodes: <Statement>*
 //                            label: SourceLabel }
@@ skipping 146 matching lines @@
 }
 
 
 void FlowGraphPrinter::VisitNativeCall(NativeCallComp* comp) {
   OS::Print("NativeCall(%s)", comp->native_name().ToCString());
 }
 
 
 void FlowGraphPrinter::VisitStoreIndexed(StoreIndexedComp* comp) {
   OS::Print("StoreIndexed(");
-  comp->placeholder()->Accept(this);
-  OS::Print(", ");
   comp->array()->Accept(this);
   OS::Print(", ");
   comp->index()->Accept(this);
   OS::Print(", ");
   comp->value()->Accept(this);
   OS::Print(")");
 }
 
 
 void FlowGraphPrinter::VisitInstanceSetter(InstanceSetterComp* comp) {
   OS::Print("InstanceSetter(");
-  comp->placeholder()->Accept(this);
-  OS::Print(", ");
   comp->receiver()->Accept(this);
   OS::Print(", ");
   comp->value()->Accept(this);
   OS::Print(")");
 }
 
 
 void FlowGraphPrinter::VisitJoinEntry(JoinEntryInstr* instr) {
   OS::Print("%2d: [join]", instr->block_number());
 }
@@ skipping 59 matching lines @@
   char* chars = reinterpret_cast<char*>(
       Isolate::Current()->current_zone()->Allocate(len));
   OS::SNPrint(chars, len, kFormat, function_name, reason);
   const Error& error = Error::Handle(
       LanguageError::New(String::Handle(String::New(chars))));
   Isolate::Current()->long_jump_base()->Jump(1, error);
 }
 
 
 }  // namespace dart