MIPS: Some more instrumentation to narrow down Failure leaks.

src/mips/code-stubs-mips.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 3947 matching lines @@
 }
 
 
 void CEntryStub::GenerateAheadOfTime() {
   CEntryStub stub(1, kDontSaveFPRegs);
   Handle<Code> code = stub.GetCode();
   code->set_is_pregenerated(true);
 }
 
 
+static void JumpIfOOM(MacroAssembler* masm,
+                      Register value,
+                      Register scratch,
+                      Label* oom_label) {
+  STATIC_ASSERT(Failure::OUT_OF_MEMORY_EXCEPTION == 3);
+  STATIC_ASSERT(kFailureTag == 3);
+  __ andi(scratch, value, 0xf);
+  __ Branch(oom_label, eq, scratch, Operand(0xf));
+}
+
+
 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) {
   // v0: result parameter for PerformGC, if any
   // s0: number of arguments including receiver (C callee-saved)
   // s1: pointer to the first argument          (C callee-saved)
   // s2: pointer to builtin function            (C callee-saved)
@@ skipping 86 matching lines @@
   __ LeaveExitFrame(save_doubles_, s0, true);
 
   // Check if we should retry or throw exception.
   Label retry;
   __ bind(&failure_returned);
   STATIC_ASSERT(Failure::RETRY_AFTER_GC == 0);
   __ andi(t0, v0, ((1 << kFailureTypeTagSize) - 1) << kFailureTagSize);
   __ Branch(&retry, eq, t0, Operand(zero_reg));
 
   // Special handling of out of memory exceptions.
-  Failure* out_of_memory = Failure::OutOfMemoryException();
-  __ Branch(USE_DELAY_SLOT,
-            throw_out_of_memory_exception,
-            eq,
-            v0,
-            Operand(reinterpret_cast<int32_t>(out_of_memory)));
-  // If we throw the OOM exception, the value of a3 doesn't matter.
-  // Any instruction can be in the delay slot that's not a jump.
+  JumpIfOOM(masm, v0, t0, throw_out_of_memory_exception);
 
   // Retrieve the pending exception and clear the variable.
   __ LoadRoot(a3, Heap::kTheHoleValueRootIndex);
   __ li(t0, Operand(ExternalReference(Isolate::kPendingExceptionAddress,
                                       isolate)));
   __ lw(v0, MemOperand(t0));
   __ sw(a3, MemOperand(t0));
 
   // Special handling of termination exceptions which are uncatchable
   // by javascript code.
@@ skipping 71 matching lines @@
   __ bind(&throw_out_of_memory_exception);
   // Set external caught exception to false.
   Isolate* isolate = masm->isolate();
   ExternalReference external_caught(Isolate::kExternalCaughtExceptionAddress,
                                     isolate);
   __ li(a0, Operand(false, RelocInfo::NONE32));
   __ li(a2, Operand(external_caught));
   __ sw(a0, MemOperand(a2));
 
   // Set pending exception and v0 to out of memory exception.
-  Failure* out_of_memory = Failure::OutOfMemoryException();
+  Label already_have_failure;
+  JumpIfOOM(masm, v0, t0, &already_have_failure);
+  Failure* out_of_memory = Failure::OutOfMemoryException(0x1);
   __ li(v0, Operand(reinterpret_cast<int32_t>(out_of_memory)));
+  __ bind(&already_have_failure);
   __ li(a2, Operand(ExternalReference(Isolate::kPendingExceptionAddress,
                                       isolate)));
   __ sw(v0, MemOperand(a2));
   // Fall through to the next label.
 
   __ bind(&throw_termination_exception);
   __ ThrowUncatchable(v0);
 
   __ bind(&throw_normal_exception);
   __ Throw(v0);
@@ skipping 3684 matching lines @@
   __ Pop(ra, t1, a1);
   __ Ret();
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_MIPS