Fix data race in cctest/test-api/RegExpInterruption

test/cctest/test-api.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 15382 matching lines @@
     v8::Local<v8::String> source =
         v8::String::NewExternal(context->GetIsolate(), uc16_resource);
     v8::Script::Compile(source);
   }
 }
 
 
 #ifndef V8_INTERPRETED_REGEXP
 
 struct RegExpInterruptionData {
-  int loop_count;
+  v8::base::Atomic32 loop_count;
   UC16VectorResource* string_resource;
   v8::Persistent<v8::String> string;
 } regexp_interruption_data;
 
 
 class RegExpInterruptionThread : public v8::base::Thread {
  public:
   explicit RegExpInterruptionThread(v8::Isolate* isolate)
       : Thread(Options("TimeoutThread")), isolate_(isolate) {}
 
   virtual void Run() {
-    for (regexp_interruption_data.loop_count = 0;
-         regexp_interruption_data.loop_count < 7;
-         regexp_interruption_data.loop_count++) {
+    for (v8::base::NoBarrier_Store(&regexp_interruption_data.loop_count, 0);
+         v8::base::NoBarrier_Load(&regexp_interruption_data.loop_count) < 7;
+         v8::base::NoBarrier_AtomicIncrement(
+             &regexp_interruption_data.loop_count, 1)) {
       v8::base::OS::Sleep(50);  // Wait a bit before requesting GC.
       reinterpret_cast<i::Isolate*>(isolate_)->stack_guard()->RequestGC();
     }
     v8::base::OS::Sleep(50);  // Wait a bit before terminating.
     v8::V8::TerminateExecution(isolate_);
   }
 
  private:
   v8::Isolate* isolate_;
 };
 
 
 void RunBeforeGC(v8::GCType type, v8::GCCallbackFlags flags) {
-  if (regexp_interruption_data.loop_count != 2) return;
+  if (v8::base::NoBarrier_Load(&regexp_interruption_data.loop_count) != 2) {
+    return;
+  }
   v8::HandleScope scope(CcTest::isolate());
   v8::Local<v8::String> string = v8::Local<v8::String>::New(
       CcTest::isolate(), regexp_interruption_data.string);
   string->MakeExternal(regexp_interruption_data.string_resource);
 }
 
 
 // Test that RegExp execution can be interrupted.  Specifically, we test
 // * interrupting with GC
 // * turn the subject string from one-byte internal to two-byte external string
@@ skipping 8258 matching lines @@
       "  var foobXXXXX";  // Too many bytes which look like incomplete chars!
   char chunk2[] =
       "r = 13;\n"
       "  return foob\xeb\x91\x80\x80\x80r;\n"
       "}\n";
   for (int i = 0; i < 5; ++i) chunk1[strlen(chunk1) - 5 + i] = reference[i];
 
   const char* chunks[] = {chunk1, chunk2, "foo();", NULL};
   RunStreamingTest(chunks, v8::ScriptCompiler::StreamedSource::UTF8, false);
 }