Compile FastCloneShallowObjectStub using Crankshaft.

src/hydrogen.cc

Index: src/hydrogen.cc
diff --git a/src/hydrogen.cc b/src/hydrogen.cc
index 00207c142f44d528805a7172698ae09cf21388a2..c792f39183e6bfe91ed7e1622d461c2fa9ee7fa8 100644
--- a/src/hydrogen.cc
+++ b/src/hydrogen.cc
@@ -633,17 +633,65 @@ HConstant* HGraph::GetConstantHole() {
 }
 
 
+HGraphBuilder::CheckBuilder::CheckBuilder(HGraphBuilder* builder, BailoutId id)
+    : builder_(builder),
+      finished_(false),
+      id_(id) {
+  HEnvironment* env = builder->environment();
+  failure_block_ = builder->CreateBasicBlock(env->Copy());
+  merge_block_ = builder->CreateBasicBlock(env->Copy());
+}
+
+
+void HGraphBuilder::CheckBuilder::CheckNotUndefined(HValue* value) {
+  HEnvironment* env = builder_->environment();
+  HIsNilAndBranch* compare =
+      new(zone()) HIsNilAndBranch(value, kStrictEquality, kUndefinedValue);
+  HBasicBlock* success_block = builder_->CreateBasicBlock(env->Copy());
+  HBasicBlock* failure_block = builder_->CreateBasicBlock(env->Copy());
+  compare->SetSuccessorAt(0, failure_block);
+  compare->SetSuccessorAt(1, success_block);
+  failure_block->Goto(failure_block_);

[Jakob Kummerow, 2013/02/08 12:45:49]

This line looks weird. Too bad the edge split form requirement doesn't allow us
to get by without it.

[Michael Starzinger, 2013/02/11 12:13:22]

Yeah, I know, it also annoys me that we need this fall-through blocks in between
and that merge blocks cannot be proceeded by other control-flow instructions
besides HGoto. But fixing that is outside the scope of this CL.

+  builder_->current_block()->Finish(compare);
+  builder_->set_current_block(success_block);
+}
+
+
+void HGraphBuilder::CheckBuilder::CheckIntegerEq(HValue* left, HValue* right) {
+  HEnvironment* env = builder_->environment();
+  HCompareIDAndBranch* compare =
+      new(zone()) HCompareIDAndBranch(left, right, Token::EQ);
+  compare->AssumeRepresentation(Representation::Integer32());
+  HBasicBlock* success_block = builder_->CreateBasicBlock(env->Copy());
+  HBasicBlock* failure_block = builder_->CreateBasicBlock(env->Copy());
+  compare->SetSuccessorAt(0, success_block);
+  compare->SetSuccessorAt(1, failure_block);
+  failure_block->Goto(failure_block_);
+  builder_->current_block()->Finish(compare);
+  builder_->set_current_block(success_block);
+}
+
+
+void HGraphBuilder::CheckBuilder::End() {
+  ASSERT(!finished_);
+  builder_->current_block()->Goto(merge_block_);
+  builder_->set_current_block(failure_block_);

[Jakob Kummerow, 2013/02/08 12:45:49]

I think this line is not needed if you
s/builder_->current_block()/failure_block_/ in the line below.

[Michael Starzinger, 2013/02/11 12:13:22]

Done.

+  builder_->current_block()->FinishExitWithDeoptimization(HDeoptimize::kUseAll);
+  failure_block_->SetJoinId(id_);
+  builder_->set_current_block(merge_block_);
+  merge_block_->SetJoinId(id_);
+  finished_ = true;
+}
+
+
 HGraphBuilder::IfBuilder::IfBuilder(HGraphBuilder* builder, BailoutId id)
     : builder_(builder),
       finished_(false),
       id_(id) {
   HEnvironment* env = builder->environment();
-  HEnvironment* true_env = env->Copy();
-  HEnvironment* false_env = env->Copy();
-  HEnvironment* merge_env = env->Copy();
-  true_block_ = builder->CreateBasicBlock(true_env);
-  false_block_ = builder->CreateBasicBlock(false_env);
-  merge_block_ = builder->CreateBasicBlock(merge_env);
+  true_block_ = builder->CreateBasicBlock(env->Copy());
+  false_block_ = builder->CreateBasicBlock(env->Copy());
+  merge_block_ = builder->CreateBasicBlock(env->Copy());
 }
 
 
@@ -685,11 +733,9 @@ HGraphBuilder::LoopBuilder::LoopBuilder(HGraphBuilder* builder,
       id_(id),
       finished_(false) {
   HEnvironment* env = builder_->environment();
-  HEnvironment* body_env = env->Copy();
-  HEnvironment* exit_env = env->Copy();
   header_block_ = builder->CreateLoopHeaderBlock();
-  body_block_ = builder->CreateBasicBlock(body_env);
-  exit_block_ = builder->CreateBasicBlock(exit_env);
+  body_block_ = builder->CreateBasicBlock(env->Copy());
+  exit_block_ = builder->CreateBasicBlock(env->Copy());
 }