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diff --git a/tensorflow/core/framework/bfloat16.h b/tensorflow/core/framework/bfloat16.h
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+++ b/tensorflow/core/framework/bfloat16.h
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+#ifndef TENSORFLOW_FRAMEWORK_BFLOAT16_H_
+#define TENSORFLOW_FRAMEWORK_BFLOAT16_H_
+
+#include "tensorflow/core/platform/port.h"
+#include "third_party/eigen3/unsupported/Eigen/CXX11/Tensor"
+
+// Compact 16-bit encoding of floating point numbers. This representation uses
+// 1 bit for the sign, 8 bits for the exponent and 7 bits for the mantissa.  It
+// is assumed that floats are in IEEE 754 format so the representation is just
+// bits 16-31 of a single precision float.
+//
+// NOTE: The IEEE floating point standard defines a float16 format that
+// is different than this format (it has fewer bits of exponent and more
+// bits of mantissa).  We don't use that format here because conversion
+// to/from 32-bit floats is more complex for that format, and the
+// conversion for this format is very simple.
+//
+// Because of the existing IEEE float16 type, we do not name our representation
+// "float16" but just use "uint16".
+//
+// <-----our 16bits float------->
+// s e e e e e e e e f f f f f f f f f f f f f f f f f f f f f f f
+// <------------------------------float-------------------------->
+// 3 3             2 2             1 1                           0
+// 1 0             3 2             5 4                           0
+//
+//
+// This type only supports conversion back and forth with float.
+//
+// This file must be compilable by nvcc.
+
+namespace tensorflow {
+struct bfloat16 {
+  EIGEN_DEVICE_FUNC bfloat16() {}
+  EIGEN_DEVICE_FUNC explicit bfloat16(const uint16_t v) : value(v) {}
+
+  uint16_t value;
+};
+
+// Conversion routines between an array of float and bfloat16 of
+// "size".
+void FloatToBFloat16(const float* src, bfloat16* dst, int64 size);
+void BFloat16ToFloat(const bfloat16* src, float* dst, int64 size);
+
+}  // namespace tensorflow
+
+namespace Eigen {
+template <>
+struct NumTraits<tensorflow::bfloat16> : GenericNumTraits<uint16_t> {};
+
+EIGEN_STRONG_INLINE bool operator==(const tensorflow::bfloat16 a,
+                                    const tensorflow::bfloat16 b) {
+  return a.value == b.value;
+}
+
+}  // namespace Eigen
+
+#endif  // TENSORFLOW_FRAMEWORK_BFLOAT16_H_