CallIC customization stubs must accept that a vector slot is cleared.

src/ia32/code-stubs-ia32.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/v8.h"
 
 #if V8_TARGET_ARCH_IA32
 
 #include "src/bootstrapper.h"
 #include "src/code-stubs.h"
@@ skipping 2357 matching lines @@
   int argc = state_.arg_count();
   ParameterCount actual(argc);
 
   EmitLoadTypeFeedbackVector(masm, ebx);
 
   __ LoadGlobalFunction(Context::ARRAY_FUNCTION_INDEX, ecx);
   __ cmp(edi, ecx);
   __ j(not_equal, &miss);
 
   __ mov(eax, arg_count());
-  __ mov(ebx, FieldOperand(ebx, edx, times_half_pointer_size,
+  __ mov(ecx, FieldOperand(ebx, edx, times_half_pointer_size,
                            FixedArray::kHeaderSize));
+
   // Verify that ecx contains an AllocationSite
-  __ AssertUndefinedOrAllocationSite(ebx);
+  Factory* factory = masm->isolate()->factory();
+  __ cmp(FieldOperand(ecx, 0), factory->allocation_site_map());

[Toon Verwaest, 2014/07/28 14:11:38]

HeapObject::kMapoffset?

+  __ j(not_equal, &miss);
+
+  __ mov(ebx, ecx);
   ArrayConstructorStub stub(masm->isolate(), arg_count());
   __ TailCallStub(&stub);
 
   __ bind(&miss);
   GenerateMiss(masm, IC::kCallIC_Customization_Miss);
 
   // The slow case, we need this no matter what to complete a call after a miss.
   CallFunctionNoFeedback(masm,
                          arg_count(),
                          true,
@@ skipping 2584 matching lines @@
                               Operand(ebp, 7 * kPointerSize),
                               NULL);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32