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diff --git a/src/gallium/auxiliary/util/u_half.h b/src/gallium/auxiliary/util/u_half.h
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+++ b/src/gallium/auxiliary/util/u_half.h
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+/**************************************************************************
+ *
+ * Copyright 2010 Luca Barbieri
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the
+ * next paragraph) shall be included in all copies or substantial
+ * portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ **************************************************************************/
+
+
+#ifndef U_HALF_H
+#define U_HALF_H
+
+#include "pipe/p_compiler.h"
+#include "util/u_math.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+extern const uint32_t util_half_to_float_mantissa_table[2048];
+extern const uint32_t util_half_to_float_exponent_table[64];
+extern const uint32_t util_half_to_float_offset_table[64];
+extern const uint16_t util_float_to_half_base_table[512];
+extern const uint8_t util_float_to_half_shift_table[512];
+
+/*
+ * Note that if the half float is a signaling NaN, the x87 FPU will turn
+ * it into a quiet NaN immediately upon loading into a float.
+ *
+ * Additionally, denormals may be flushed to zero.
+ *
+ * To avoid this, use the floatui functions instead of the float ones
+ * when just doing conversion rather than computation on the resulting
+ * floats.
+ */
+
+static INLINE uint32_t
+util_half_to_floatui(uint16_t h)
+{
+   unsigned exp = h >> 10;
+   return util_half_to_float_mantissa_table[util_half_to_float_offset_table[exp] + (h & 0x3ff)] + util_half_to_float_exponent_table[exp];
+}
+
+static INLINE float
+util_half_to_float(uint16_t h)
+{
+   union fi r;
+   r.ui = util_half_to_floatui(h);
+   return r.f;
+}
+
+static INLINE uint16_t
+util_floatui_to_half(uint32_t v)
+{
+   unsigned signexp = v >> 23;
+   return util_float_to_half_base_table[signexp] + ((v & 0x007fffff) >> util_float_to_half_shift_table[signexp]);
+}
+
+static INLINE uint16_t
+util_float_to_half(float f)
+{
+   union fi i;
+   i.f = f;
+   return util_floatui_to_half(i.ui);
+}
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* U_HALF_H */
+