Make ShaderTranslatorCache thread safe

gpu/command_buffer/service/shader_translator.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "gpu/command_buffer/service/shader_translator.h"
 
 #include <string.h>
 #include <algorithm>
 
 #include "base/at_exit.h"
 #include "base/debug/trace_event.h"
+#include "base/lazy_instance.h"
 #include "base/logging.h"
 #include "base/strings/string_number_conversions.h"
 
 namespace {
 
 using gpu::gles2::ShaderTranslator;
 
-bool g_translator_initialized = false;
-
-void FinalizeShaderTranslator(void* /* dummy */) {
-  TRACE_EVENT0("gpu", "ShFinalize");
-  ShFinalize();
-  g_translator_initialized = false;
-}
-
-bool InitializeShaderTranslator() {
-  if (!g_translator_initialized) {
+class ShaderTranslatorInitializer {
+ public:
+  ShaderTranslatorInitializer() {
     TRACE_EVENT0("gpu", "ShInitialize");
     CHECK(ShInitialize());
-    base::AtExitManager::RegisterCallback(&FinalizeShaderTranslator, NULL);
-    g_translator_initialized = true;
   }
-  return g_translator_initialized;
-}
+
+  ~ShaderTranslatorInitializer() {
+    TRACE_EVENT0("gpu", "ShFinalize");
+    ShFinalize();
+  }
+};
+
+base::LazyInstance<ShaderTranslatorInitializer> g_translator_initializer =
+    LAZY_INSTANCE_INITIALIZER;
 
 #if !defined(ANGLE_SH_VERSION) || ANGLE_SH_VERSION < 108
 typedef int ANGLEGetInfoType;
 #else
 typedef size_t ANGLEGetInfoType;
 #endif
 
 void GetVariableInfo(ShHandle compiler, ShShaderInfo var_type,
                      ShaderTranslator::VariableMap* var_map) {
   ANGLEGetInfoType name_len = 0, mapped_name_len = 0;
@@ skipping 82 matching lines @@
     ShShaderSpec shader_spec,
     const ShBuiltInResources* resources,
     ShaderTranslatorInterface::GlslImplementationType glsl_implementation_type,
     ShCompileOptions driver_bug_workarounds) {
   // Make sure Init is called only once.
   DCHECK(compiler_ == NULL);
   DCHECK(shader_type == SH_FRAGMENT_SHADER || shader_type == SH_VERTEX_SHADER);
   DCHECK(shader_spec == SH_GLES2_SPEC || shader_spec == SH_WEBGL_SPEC);
   DCHECK(resources != NULL);
 
-  if (!InitializeShaderTranslator())
-    return false;
+  g_translator_initializer.Get();
 
   ShShaderOutput shader_output =
       (glsl_implementation_type == kGlslES ? SH_ESSL_OUTPUT : SH_GLSL_OUTPUT);
 
   {
     TRACE_EVENT0("gpu", "ShConstructCompiler");
     compiler_ = ShConstructCompiler(
         shader_type, shader_spec, shader_output, resources);
   }
   compiler_options_ = *resources;
@@ skipping 178 matching lines @@
   info_log_.reset();
   attrib_map_.clear();
   uniform_map_.clear();
   varying_map_.clear();
   name_map_.clear();
 }
 
 }  // namespace gles2
 }  // namespace gpu