Defer creating Handles for HConstants to the code generation phase.

src/hydrogen.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 561 matching lines @@
   if (!pointer->is_set()) {
     HConstant* constant = new(zone()) HConstant(value,
                                                 Representation::Tagged());
     constant->InsertAfter(GetConstantUndefined());
     pointer->set(constant);
   }
   return pointer->get();
 }
 
 
+HConstant* HGraph::GetConstantInt32(SetOncePointer<HConstant>* pointer,
+                                    int32_t value) {
+  if (!pointer->is_set()) {
+    HConstant* constant =
+        new(zone()) HConstant(value, Representation::Integer32());
+    constant->InsertAfter(GetConstantUndefined());
+    pointer->set(constant);
+  }
+  return pointer->get();
+}
+
+
 HConstant* HGraph::GetConstant1() {
-  return GetConstant(&constant_1_, Handle<Smi>(Smi::FromInt(1)));
+  return GetConstantInt32(&constant_1_, 1);
 }
 
 
 HConstant* HGraph::GetConstantMinus1() {
-  return GetConstant(&constant_minus1_, Handle<Smi>(Smi::FromInt(-1)));
+  return GetConstantInt32(&constant_minus1_, -1);
 }
 
 
 HConstant* HGraph::GetConstantTrue() {
   return GetConstant(&constant_true_, isolate()->factory()->true_value());
 }
 
 
 HConstant* HGraph::GetConstantFalse() {
   return GetConstant(&constant_false_, isolate()->factory()->false_value());
@@ skipping 2445 matching lines @@
   for (int i = 0; i < exprs->length(); ++i) {
     CHECK_ALIVE(VisitForValue(exprs->at(i)));
   }
 }
 
 
 HGraph* HGraphBuilder::CreateGraph() {
   graph_ = new(zone()) HGraph(info());
   if (FLAG_hydrogen_stats) HStatistics::Instance()->Initialize(info());
 
+  Factory* f = info()->isolate()->factory();

[Michael Starzinger, 2012/07/10 12:05:51]

I don't think this change is actually needed.

+  constant_undefined_ = new(zone()) HConstant(f->undefined_value(),
+                                              Representation::Tagged());
+  constant_null_ = new(zone()) HConstant(f->null_value(),
+                                         Representation::Tagged());
+
   {
     HPhase phase("H_Block building");
     CompilationHandleScope handle_scope(info());
     current_block_ = graph()->entry_block();
 
     Scope* scope = info()->scope();
     if (scope->HasIllegalRedeclaration()) {
       Bailout("function with illegal redeclaration");
       return NULL;
     }
@@ skipping 4801 matching lines @@
       instr = HShl::NewHShl(zone(), context, left, right);
       break;
     default:
       UNREACHABLE();
   }
 
   // If we hit an uninitialized binary op stub we will get type info
   // for a smi operation. If one of the operands is a constant string
   // do not generate code assuming it is a smi operation.
   if (info.IsSmi() &&
-      ((left->IsConstant() && HConstant::cast(left)->HasStringValue()) ||
-       (right->IsConstant() && HConstant::cast(right)->HasStringValue()))) {
+      ((left->IsConstant() && HConstant::cast(left)->handle()->IsString()) ||
+       (right->IsConstant() && HConstant::cast(right)->handle()->IsString()))) {
     return instr;
   }
   Representation rep = ToRepresentation(info);
   // We only generate either int32 or generic tagged bitwise operations.
   if (instr->IsBitwiseBinaryOperation()) {
     HBitwiseBinaryOperation::cast(instr)->
          InitializeObservedInputRepresentation(rep);
     if (rep.IsDouble()) rep = Representation::Integer32();
   }
   TraceRepresentation(expr->op(), info, instr, rep);
@@ skipping 177 matching lines @@
   HValue* value = typeof_expr->value();
   HTypeofIsAndBranch* instr = new(zone()) HTypeofIsAndBranch(value, check);
   instr->set_position(expr->position());
   return ast_context()->ReturnControl(instr, expr->id());
 }
 
 
 static bool MatchLiteralCompareNil(HValue* left,
                                    Token::Value op,
                                    HValue* right,
-                                   Handle<Object> nil,
+                                   HConstant* nil,

[Michael Starzinger, 2012/07/10 12:05:51]

I don't think any of the changes in this file from this point on are actually
needed.

                                    HValue** expr) {
+  ASSERT(nil->IsTagged());
   if (left->IsConstant() &&
-      HConstant::cast(left)->handle().is_identical_to(nil) &&
+      HConstant::cast(left)->IsTagged() &&
+      HConstant::cast(left)->handle().is_identical_to(nil->handle()) &&
       Token::IsEqualityOp(op)) {
     *expr = right;
     return true;
   }
   return false;
 }
 
 
 static bool MatchLiteralCompareTypeof(HValue* left,
                                       Token::Value op,
                                       HValue* right,
                                       HTypeof** typeof_expr,
                                       Handle<String>* check) {
   if (left->IsTypeof() &&
       Token::IsEqualityOp(op) &&
       right->IsConstant() &&
-      HConstant::cast(right)->HasStringValue()) {
+      HConstant::cast(right)->handle()->IsString()) {
     *typeof_expr = HTypeof::cast(left);
     *check = Handle<String>::cast(HConstant::cast(right)->handle());
     return true;
   }
   return false;
 }
 
 
 static bool IsLiteralCompareTypeof(HValue* left,
                                    Token::Value op,
                                    HValue* right,
                                    HTypeof** typeof_expr,
                                    Handle<String>* check) {
   return MatchLiteralCompareTypeof(left, op, right, typeof_expr, check) ||
       MatchLiteralCompareTypeof(right, op, left, typeof_expr, check);
 }
 
 
 static bool IsLiteralCompareNil(HValue* left,
                                 Token::Value op,
                                 HValue* right,
-                                Handle<Object> nil,
+                                HConstant* nil,
                                 HValue** expr) {
   return MatchLiteralCompareNil(left, op, right, nil, expr) ||
       MatchLiteralCompareNil(right, op, left, nil, expr);
 }
 
 
 static bool IsLiteralCompareBool(HValue* left,
                                  Token::Value op,
                                  HValue* right) {
   return op == Token::EQ_STRICT &&
-      ((left->IsConstant() && HConstant::cast(left)->handle()->IsBoolean()) ||
-       (right->IsConstant() && HConstant::cast(right)->handle()->IsBoolean()));
+      ((left->IsConstant() &&
+        HConstant::cast(left)->handle()->IsBoolean()) ||
+       (right->IsConstant() &&
+        HConstant::cast(right)->handle()->IsBoolean()));
 }
 
 
 void HGraphBuilder::VisitCompareOperation(CompareOperation* expr) {
   ASSERT(!HasStackOverflow());
   ASSERT(current_block() != NULL);
   ASSERT(current_block()->HasPredecessor());
   if (IsClassOfTest(expr)) {
     CallRuntime* call = expr->left()->AsCallRuntime();
     ASSERT(call->arguments()->length() == 1);
@@ skipping 23 matching lines @@
   HValue* right = Pop();
   HValue* left = Pop();
   Token::Value op = expr->op();
 
   HTypeof* typeof_expr = NULL;
   Handle<String> check;
   if (IsLiteralCompareTypeof(left, op, right, &typeof_expr, &check)) {
     return HandleLiteralCompareTypeof(expr, typeof_expr, check);
   }
   HValue* sub_expr = NULL;
-  Factory* f = graph()->isolate()->factory();
-  if (IsLiteralCompareNil(left, op, right, f->undefined_value(), &sub_expr)) {
+  if (IsLiteralCompareNil(left, op, right, constant_undefined_, &sub_expr)) {
     return HandleLiteralCompareNil(expr, sub_expr, kUndefinedValue);
   }
-  if (IsLiteralCompareNil(left, op, right, f->null_value(), &sub_expr)) {
+  if (IsLiteralCompareNil(left, op, right, constant_null_, &sub_expr)) {
     return HandleLiteralCompareNil(expr, sub_expr, kNullValue);
   }
   if (IsLiteralCompareBool(left, op, right)) {
     HCompareObjectEqAndBranch* result =
         new(zone()) HCompareObjectEqAndBranch(left, right);
     result->set_position(expr->position());
     return ast_context()->ReturnControl(result, expr->id());
   }
 
   if (op == Token::INSTANCEOF) {
@@ skipping 1332 matching lines @@
     }
   }
 
 #ifdef DEBUG
   if (graph_ != NULL) graph_->Verify(false);  // No full verify.
   if (allocator_ != NULL) allocator_->Verify();
 #endif
 }
 
 } }  // namespace v8::internal