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author | marha <marha@users.sourceforge.net> | 2015-03-22 14:10:47 +0100 |
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committer | marha <marha@users.sourceforge.net> | 2015-03-22 14:10:47 +0100 |
commit | 3bc24b271f45f9f33484b8cf53b44f33f7e8a237 (patch) | |
tree | 193651a94adb3804e800747e993d07b92688e4d4 /mesalib/src/util/rounding.h | |
parent | c646056120fe14e4c4ccf81bac5d78d61225a8e8 (diff) | |
parent | 82c8df11062f72a7d467e26cedbbd8b322ff7a70 (diff) | |
download | vcxsrv-3bc24b271f45f9f33484b8cf53b44f33f7e8a237.tar.gz vcxsrv-3bc24b271f45f9f33484b8cf53b44f33f7e8a237.tar.bz2 vcxsrv-3bc24b271f45f9f33484b8cf53b44f33f7e8a237.zip |
Merge remote-tracking branch 'origin/released'
Conflicts:
mesalib/src/mapi/glapi/glapi.h
mesalib/src/mapi/glapi/glapi_nop.c
mesalib/src/mesa/main/bufferobj.c
Diffstat (limited to 'mesalib/src/util/rounding.h')
-rw-r--r-- | mesalib/src/util/rounding.h | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/mesalib/src/util/rounding.h b/mesalib/src/util/rounding.h new file mode 100644 index 000000000..0cbe9269f --- /dev/null +++ b/mesalib/src/util/rounding.h @@ -0,0 +1,78 @@ +/* + * Copyright © 2015 Intel Corporation + * + * 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 AUTHORS OR COPYRIGHT HOLDERS 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. + */ + +#include <math.h> + +#ifdef __SSE4_1__ +#include <smmintrin.h> +#endif + +/* The C standard library has functions round()/rint()/nearbyint() that round + * their arguments according to the rounding mode set in the floating-point + * control register. While there are trunc()/ceil()/floor() functions that do + * a specific operation without modifying the rounding mode, there is no + * roundeven() in any version of C. + * + * Technical Specification 18661 (ISO/IEC TS 18661-1:2014) adds roundeven(), + * but it's unfortunately not implemented by glibc. + * + * This implementation differs in that it does not raise the inexact exception. + * + * We use rint() to implement these functions, with the assumption that the + * floating-point rounding mode has not been changed from the default Round + * to Nearest. + */ + +/** + * \brief Rounds \c x to the nearest integer, with ties to the even integer. + */ +static inline float +_mesa_roundevenf(float x) +{ +#ifdef __SSE4_1__ + float ret; + __m128 m = _mm_load_ss(&x); + m = _mm_round_ss(m, m, _MM_FROUND_CUR_DIRECTION | _MM_FROUND_NO_EXC); + _mm_store_ss(&ret, m); + return ret; +#else + return rintf(x); +#endif +} + +/** + * \brief Rounds \c x to the nearest integer, with ties to the even integer. + */ +static inline double +_mesa_roundeven(double x) +{ +#ifdef __SSE4_1__ + double ret; + __m128d m = _mm_load_sd(&x); + m = _mm_round_sd(m, m, _MM_FROUND_CUR_DIRECTION | _MM_FROUND_NO_EXC); + _mm_store_sd(&ret, m); + return ret; +#else + return rint(x); +#endif +} |