/* * 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. */ #ifndef _ROUNDING_H #define _ROUNDING_H #include "c99_math.h" #include <limits.h> #include <stdint.h> #ifdef __x86_64__ #include <xmmintrin.h> #include <emmintrin.h> #endif #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 } /** * \brief Rounds \c x to the nearest integer, with ties to the even integer, * and returns the value as a long int. */ static inline long _mesa_lroundevenf(float x) { #ifdef __x86_64__ #if LONG_MAX == INT64_MAX return _mm_cvtss_si64(_mm_load_ss(&x)); #elif LONG_MAX == INT32_MAX return _mm_cvtss_si32(_mm_load_ss(&x)); #else #error "Unsupported long size" #endif #else return lrintf(x); #endif } /** * \brief Rounds \c x to the nearest integer, with ties to the even integer, * and returns the value as a long int. */ static inline long _mesa_lroundeven(double x) { #ifdef __x86_64__ #if LONG_MAX == INT64_MAX return _mm_cvtsd_si64(_mm_load_sd(&x)); #elif LONG_MAX == INT32_MAX return _mm_cvtsd_si32(_mm_load_sd(&x)); #else #error "Unsupported long size" #endif #else return lrint(x); #endif } #endif