Array constructor can be simplified by loading context from JSFunction.

src/code-stubs-hydrogen.cc

Index: src/code-stubs-hydrogen.cc
diff --git a/src/code-stubs-hydrogen.cc b/src/code-stubs-hydrogen.cc
index 374f55f06879ffe12ecf7685f39f450d4eaa98dc..783384d45285f3e5325038a34ea6d3705e45042e 100644
--- a/src/code-stubs-hydrogen.cc
+++ b/src/code-stubs-hydrogen.cc
@@ -81,24 +81,6 @@ class CodeStubGraphBuilderBase : public HGraphBuilder {
   HContext* context() { return context_; }
   Isolate* isolate() { return info_.isolate(); }
 
-  class ArrayContextChecker {
-   public:
-    ArrayContextChecker(HGraphBuilder* builder, HValue* constructor,
-                        HValue* array_function)
-        : checker_(builder) {
-      checker_.If<HCompareObjectEqAndBranch, HValue*>(constructor,
-                                                      array_function);
-      checker_.Then();
-    }
-
-    ~ArrayContextChecker() {
-      checker_.ElseDeopt("Array constructor called from different context");
-      checker_.End();
-    }
-   private:
-    IfBuilder checker_;
-  };
-
   enum ArgumentClass {
     NONE,
     SINGLE,
@@ -106,7 +88,6 @@ class CodeStubGraphBuilderBase : public HGraphBuilder {
   };
 
   HValue* BuildArrayConstructor(ElementsKind kind,
-                                ContextCheckMode context_mode,
                                 AllocationSiteOverrideMode override_mode,
                                 ArgumentClass argument_class);
   HValue* BuildInternalArrayConstructor(ElementsKind kind,
@@ -672,15 +653,9 @@ Handle<Code> TransitionElementsKindStub::GenerateCode(Isolate* isolate) {
 
 HValue* CodeStubGraphBuilderBase::BuildArrayConstructor(
     ElementsKind kind,
-    ContextCheckMode context_mode,
     AllocationSiteOverrideMode override_mode,
     ArgumentClass argument_class) {
   HValue* constructor = GetParameter(ArrayConstructorStubBase::kConstructor);
-  if (context_mode == CONTEXT_CHECK_REQUIRED) {
-    HInstruction* array_function = BuildGetArrayFunction();
-    ArrayContextChecker checker(this, constructor, array_function);
-  }
-
   HValue* property_cell = GetParameter(ArrayConstructorStubBase::kPropertyCell);
   // Walk through the property cell to the AllocationSite
   HValue* alloc_site = Add<HLoadNamedField>(property_cell,
@@ -787,9 +762,8 @@ HValue* CodeStubGraphBuilderBase::BuildArrayNArgumentsConstructor(
 template <>
 HValue* CodeStubGraphBuilder<ArrayNoArgumentConstructorStub>::BuildCodeStub() {
   ElementsKind kind = casted_stub()->elements_kind();
-  ContextCheckMode context_mode = casted_stub()->context_mode();
   AllocationSiteOverrideMode override_mode = casted_stub()->override_mode();
-  return BuildArrayConstructor(kind, context_mode, override_mode, NONE);
+  return BuildArrayConstructor(kind, override_mode, NONE);
 }
 
 
@@ -802,9 +776,8 @@ template <>
 HValue* CodeStubGraphBuilder<ArraySingleArgumentConstructorStub>::
     BuildCodeStub() {
   ElementsKind kind = casted_stub()->elements_kind();
-  ContextCheckMode context_mode = casted_stub()->context_mode();
   AllocationSiteOverrideMode override_mode = casted_stub()->override_mode();
-  return BuildArrayConstructor(kind, context_mode, override_mode, SINGLE);
+  return BuildArrayConstructor(kind, override_mode, SINGLE);
 }
 
 
@@ -817,9 +790,8 @@ Handle<Code> ArraySingleArgumentConstructorStub::GenerateCode(
 template <>
 HValue* CodeStubGraphBuilder<ArrayNArgumentsConstructorStub>::BuildCodeStub() {
   ElementsKind kind = casted_stub()->elements_kind();
-  ContextCheckMode context_mode = casted_stub()->context_mode();
   AllocationSiteOverrideMode override_mode = casted_stub()->override_mode();
-  return BuildArrayConstructor(kind, context_mode, override_mode, MULTIPLE);
+  return BuildArrayConstructor(kind, override_mode, MULTIPLE);
 }