Implement subclassing Arrays.

src/ia32/code-stubs-ia32.cc

Index: src/ia32/code-stubs-ia32.cc
diff --git a/src/ia32/code-stubs-ia32.cc b/src/ia32/code-stubs-ia32.cc
index fff1e2fda32749257fcff41646e4812c6920a74b..fd2de71b203cba9859d3b3bb8911a60adc37f611 100644
--- a/src/ia32/code-stubs-ia32.cc
+++ b/src/ia32/code-stubs-ia32.cc
@@ -4662,9 +4662,6 @@ void ArrayConstructorStub::Generate(MacroAssembler* masm) {
   __ cmp(ebx, isolate()->factory()->undefined_value());
   __ j(equal, &no_info);
 
-  __ cmp(edx, edi);
-  __ j(not_equal, &subclassing);
-
   // Only look at the lower 16 bits of the transition info.
   __ mov(edx, FieldOperand(ebx, AllocationSite::kTransitionInfoOffset));
   __ SmiUntag(edx);
@@ -4676,7 +4673,13 @@ void ArrayConstructorStub::Generate(MacroAssembler* masm) {
   GenerateDispatchToArrayStub(masm, DISABLE_ALLOCATION_SITES);
 
   __ bind(&subclassing);
-  __ TailCallRuntime(Runtime::kThrowArrayNotSubclassableError, 0, 1);
+  __ pop(ecx);  // return address.
+  __ push(edi);
+  __ push(edx);
+  __ add(eax, Immediate(2));

[mvstanton, 2015/03/02 16:46:18]

A comment about the add would be good, or maybe an overview comment indicating
that you are cleverly altering the arguments length.

+  __ push(ecx);
+  __ JumpToExternalReference(
+      ExternalReference(Runtime::kArrayConstructorWithSubclassing, isolate()));
 }