Fix a crash caused by garbage collection during generation of a...

src/ia32/macro-assembler-ia32.cc

Index: src/ia32/macro-assembler-ia32.cc
===================================================================
--- src/ia32/macro-assembler-ia32.cc	(revision 3434)
+++ src/ia32/macro-assembler-ia32.cc	(working copy)
@@ -1015,17 +1015,37 @@
 
 
 void MacroAssembler::CallStub(CodeStub* stub) {
-  ASSERT(allow_stub_calls());  // calls are not allowed in some stubs
+  ASSERT(allow_stub_calls());  // Calls are not allowed in some stubs.
   call(stub->GetCode(), RelocInfo::CODE_TARGET);
 }
 
 
+Object* MacroAssembler::TryCallStub(CodeStub* stub) {
+  ASSERT(allow_stub_calls());  // Calls are not allowed in some stubs.
+  Object* result = stub->TryGetCode();
+  if (!result->IsFailure()) {
+    call(Handle<Code>(Code::cast(result)), RelocInfo::CODE_TARGET);
+  }
+  return result;
+}
+
+
 void MacroAssembler::TailCallStub(CodeStub* stub) {
-  ASSERT(allow_stub_calls());  // calls are not allowed in some stubs
+  ASSERT(allow_stub_calls());  // Calls are not allowed in some stubs.
   jmp(stub->GetCode(), RelocInfo::CODE_TARGET);
 }
 
 
+Object* MacroAssembler::TryTailCallStub(CodeStub* stub) {
+  ASSERT(allow_stub_calls());  // Calls are not allowed in some stubs.
+  Object* result = stub->TryGetCode();
+  if (!result->IsFailure()) {
+    jmp(Handle<Code>(Code::cast(result)), RelocInfo::CODE_TARGET);
+  }
+  return result;
+}
+
+
 void MacroAssembler::StubReturn(int argc) {
   ASSERT(argc >= 1 && generating_stub());
   ret((argc - 1) * kPointerSize);