Initial import.

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diff --git a/chromium/gpu/command_buffer/common/bitfield_helpers.h b/chromium/gpu/command_buffer/common/bitfield_helpers.h
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+// Copyright (c) 2009 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.
+
+// This file contains a helper template class used to access bit fields in
+// unsigned int_ts.
+
+#ifndef GPU_COMMAND_BUFFER_COMMON_BITFIELD_HELPERS_H_
+#define GPU_COMMAND_BUFFER_COMMON_BITFIELD_HELPERS_H_
+
+namespace gpu {
+
+// Bitfield template class, used to access bit fields in unsigned int_ts.
+template<int shift, int length> class BitField {
+ public:
+  static const unsigned int kShift = shift;
+  static const unsigned int kLength = length;
+  // the following is really (1<<length)-1 but also work for length == 32
+  // without compiler warning.
+  static const unsigned int kMask = 1U + ((1U << (length-1)) - 1U) * 2U;
+
+  // Gets the value contained in this field.
+  static unsigned int Get(unsigned int container) {
+    return (container >> kShift) & kMask;
+  }
+
+  // Makes a value that can be or-ed into this field.
+  static unsigned int MakeValue(unsigned int value) {
+    return (value & kMask) << kShift;
+  }
+
+  // Changes the value of this field.
+  static void Set(unsigned int *container, unsigned int field_value) {
+    *container = (*container & ~(kMask << kShift)) | MakeValue(field_value);
+  }
+};
+
+}  // namespace gpu
+
+#endif  // GPU_COMMAND_BUFFER_COMMON_BITFIELD_HELPERS_H_