Replace ICStub for array.length with hydrogen stub

src/code-stubs-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 12 matching lines @@
 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 #include "v8.h"
 
 #include "code-stubs.h"
 #include "hydrogen.h"
 #include "lithium.h"
+#include "stub-cache.h"
 
 namespace v8 {
 namespace internal {
 
 
 static LChunk* OptimizeGraph(HGraph* graph) {
   Isolate* isolate =  graph->isolate();
   AssertNoAllocation no_gc;
   NoHandleAllocation no_handles(isolate);
   NoHandleDereference no_deref(isolate);
@@ skipping 187 matching lines @@
 
 
 Handle<Code> KeyedLoadFastElementStub::GenerateCode() {
   CodeStubGraphBuilder<KeyedLoadFastElementStub> builder(this);
   LChunk* chunk = OptimizeGraph(builder.CreateGraph());
   return chunk->Codegen(Code::COMPILED_STUB);
 }
 
 
 template <>
+HValue* CodeStubGraphBuilder<FastArrayLengthStub>::BuildCodeStub() {
+  HInstruction* load = BuildFastArrayLengthLoad(GetParameter(0));
+  AddInstruction(load);
+  return load;
+}
+
+
+Handle<Code> FastArrayLengthStub::GenerateCode() {
+  CodeStubGraphBuilder<FastArrayLengthStub> builder(this);
+  LChunk* chunk = OptimizeGraph(builder.CreateGraph());
+  return chunk->Codegen(Code::COMPILED_STUB);
+}
+
+void FastArrayLengthStub::InitializeInterfaceDescriptor(
+    Isolate* isolate,
+    CodeStubInterfaceDescriptor* descriptor) {
+  descriptor->register_param_count_ = 2;

[danno, 2013/03/12 11:16:16]

Descriptors are persistent, but the lifetime of registers_ is not. 

+  // See LoadStubCompiler::registers().
+  registers_[0] = receiver_;
+  registers_[1] = LoadStubCompiler::name();
+  descriptor->register_params_ = registers_;
+  descriptor->deoptimization_handler_ =
+      Runtime::FunctionForId(Runtime::kUnexpectedDeopt)->entry;
+}
+
+
+template <>
 HValue* CodeStubGraphBuilder<TransitionElementsKindStub>::BuildCodeStub() {
   Zone* zone = this->zone();
 
   HValue* js_array = GetParameter(0);
   HValue* map = GetParameter(1);
 
   info()->MarkAsSavesCallerDoubles();
 
   AddInstruction(new(zone) HTrapAllocationMemento(js_array));
 
@@ skipping 126 matching lines @@
 }
 
 
 Handle<Code> ArrayNArgumentsConstructorStub::GenerateCode() {
   CodeStubGraphBuilder<ArrayNArgumentsConstructorStub> builder(this);
   LChunk* chunk = OptimizeGraph(builder.CreateGraph());
   return chunk->Codegen(Code::COMPILED_STUB);
 }
 
 } }  // namespace v8::internal