Some more instrumentation to narrow down Failure leaks.

src/x64/code-stubs-x64.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 3881 matching lines @@
 
 
 void CEntryStub::GenerateAheadOfTime() {
   CEntryStub stub(1, kDontSaveFPRegs);
   stub.GetCode()->set_is_pregenerated(true);
   CEntryStub save_doubles(1, kSaveFPRegs);
   save_doubles.GetCode()->set_is_pregenerated(true);
 }
 
 
+static void JumpIfOOM(MacroAssembler* masm,
+                      Register value,
+                      Register scratch,
+                      Label* oom_label) {
+  __ movq(scratch, value);
+  STATIC_ASSERT(Failure::OUT_OF_MEMORY_EXCEPTION == 3);
+  STATIC_ASSERT(kFailureTag == 3);
+  __ and_(scratch, Immediate(0xf));
+  __ cmpq(scratch, Immediate(0xf));
+  __ j(equal, oom_label);
+}
+
+
 void CEntryStub::GenerateCore(MacroAssembler* masm,
                               Label* throw_normal_exception,
                               Label* throw_termination_exception,
                               Label* throw_out_of_memory_exception,
                               bool do_gc,
                               bool always_allocate_scope) {
   // rax: result parameter for PerformGC, if any.
   // rbx: pointer to C function  (C callee-saved).
   // rbp: frame pointer  (restored after C call).
   // rsp: stack pointer  (restored after C call).
@@ skipping 93 matching lines @@
   // Handling of failure.
   __ bind(&failure_returned);
 
   Label retry;
   // If the returned exception is RETRY_AFTER_GC continue at retry label
   STATIC_ASSERT(Failure::RETRY_AFTER_GC == 0);
   __ testl(rax, Immediate(((1 << kFailureTypeTagSize) - 1) << kFailureTagSize));
   __ j(zero, &retry, Label::kNear);
 
   // Special handling of out of memory exceptions.
-  __ movq(kScratchRegister, Failure::OutOfMemoryException(), RelocInfo::NONE64);
-  __ cmpq(rax, kScratchRegister);
-  __ j(equal, throw_out_of_memory_exception);
+  JumpIfOOM(masm, rax, kScratchRegister, throw_out_of_memory_exception);
 
   // Retrieve the pending exception and clear the variable.
   ExternalReference pending_exception_address(
       Isolate::kPendingExceptionAddress, masm->isolate());
   Operand pending_exception_operand =
       masm->ExternalOperand(pending_exception_address);
   __ movq(rax, pending_exception_operand);
   __ LoadRoot(rdx, Heap::kTheHoleValueRootIndex);
   __ movq(pending_exception_operand, rdx);
 
@@ skipping 76 matching lines @@
   // Set external caught exception to false.
   Isolate* isolate = masm->isolate();
   ExternalReference external_caught(Isolate::kExternalCaughtExceptionAddress,
                                     isolate);
   __ Set(rax, static_cast<int64_t>(false));
   __ Store(external_caught, rax);
 
   // Set pending exception and rax to out of memory exception.
   ExternalReference pending_exception(Isolate::kPendingExceptionAddress,
                                       isolate);
-  __ movq(rax, Failure::OutOfMemoryException(), RelocInfo::NONE64);
+  Label already_have_failure;
+  JumpIfOOM(masm, rax, kScratchRegister, &already_have_failure);
+  __ movq(rax, Failure::OutOfMemoryException(0x1), RelocInfo::NONE64);
+  __ bind(&already_have_failure);
   __ Store(pending_exception, rax);
   // Fall through to the next label.
 
   __ bind(&throw_termination_exception);
   __ ThrowUncatchable(rax);
 
   __ bind(&throw_normal_exception);
   __ Throw(rax);
 }
 
@@ skipping 2359 matching lines @@
 #endif
 
   __ Ret();
 }
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64