[proxies] fix access issue when having proxies on the prototype-chain of global objects.

src/x64/code-stubs-x64.cc

 // Copyright 2013 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.
 
 #if V8_TARGET_ARCH_X64
 
 #include "src/bootstrapper.h"
 #include "src/code-stubs.h"
 #include "src/codegen.h"
 #include "src/ic/handler-compiler.h"
@@ skipping 2499 matching lines @@
   __ bind(&function_prototype_valid);
   __ AssertNotSmi(function_prototype);
 
   // Update the global instanceof cache with the current {object} map and
   // {function}.  The cached answer will be set when it is known below.
   __ StoreRoot(function, Heap::kInstanceofCacheFunctionRootIndex);
   __ StoreRoot(object_map, Heap::kInstanceofCacheMapRootIndex);
 
   // Loop through the prototype chain looking for the {function} prototype.
   // Assume true, and change to false if not found.
-  Label done, loop, proxy_case;
+  Label done, loop, fast_runtime_fallback;
   __ LoadRoot(rax, Heap::kTrueValueRootIndex);
   __ bind(&loop);
+
+  __ testb(FieldOperand(object_map, Map::kBitFieldOffset),
+           Immediate(1 << Map::kIsAccessCheckNeeded));
+  __ j(not_zero, &fast_runtime_fallback, Label::kNear);
   __ CmpInstanceType(object_map, JS_PROXY_TYPE);
-  __ j(equal, &proxy_case, Label::kNear);
+  __ j(equal, &fast_runtime_fallback, Label::kNear);
+
   __ movp(object, FieldOperand(object_map, Map::kPrototypeOffset));
   __ cmpp(object, function_prototype);
   __ j(equal, &done, Label::kNear);
   __ CompareRoot(object, Heap::kNullValueRootIndex);
   __ movp(object_map, FieldOperand(object, HeapObject::kMapOffset));
   __ j(not_equal, &loop);
   __ LoadRoot(rax, Heap::kFalseValueRootIndex);
   __ bind(&done);
   __ StoreRoot(rax, Heap::kInstanceofCacheAnswerRootIndex);
   __ ret(0);
 
-  // Proxy-case: Call the %HasInPrototypeChain runtime function.
-  __ bind(&proxy_case);
+  // Found Proxy or access check needed: Call the runtime.
+  __ bind(&fast_runtime_fallback);
   __ PopReturnAddressTo(kScratchRegister);
   __ Push(object);
   __ Push(function_prototype);
   __ PushReturnAddressFrom(kScratchRegister);
   // Invalidate the instanceof cache.
   __ Move(rax, Smi::FromInt(0));
   __ StoreRoot(rax, Heap::kInstanceofCacheFunctionRootIndex);
   __ TailCallRuntime(Runtime::kHasInPrototypeChain, 2, 1);
 
   // Slow-case: Call the %InstanceOf runtime function.
@@ skipping 2845 matching lines @@
                            kStackSpace, nullptr, return_value_operand, NULL);
 }
 
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_X64