1130144Sdas/*- 2143708Sdas * Copyright (c) 2004-2005 David Schultz <das@FreeBSD.ORG> 3130144Sdas * All rights reserved. 4130144Sdas * 5130144Sdas * Redistribution and use in source and binary forms, with or without 6130144Sdas * modification, are permitted provided that the following conditions 7130144Sdas * are met: 8130144Sdas * 1. Redistributions of source code must retain the above copyright 9130144Sdas * notice, this list of conditions and the following disclaimer. 10130144Sdas * 2. Redistributions in binary form must reproduce the above copyright 11130144Sdas * notice, this list of conditions and the following disclaimer in the 12130144Sdas * documentation and/or other materials provided with the distribution. 13130144Sdas * 14130144Sdas * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15130144Sdas * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16130144Sdas * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17130144Sdas * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18130144Sdas * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19130144Sdas * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20130144Sdas * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21130144Sdas * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22130144Sdas * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23130144Sdas * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24130144Sdas * SUCH DAMAGE. 25130144Sdas * 26130144Sdas * $FreeBSD$ 27130144Sdas */ 28130144Sdas 29130144Sdas#ifndef _FENV_H_ 30130144Sdas#define _FENV_H_ 31130144Sdas 32130144Sdas#include <sys/cdefs.h> 33130144Sdas#include <sys/_types.h> 34130144Sdas 35143769Sdas/* 36143769Sdas * To preserve binary compatibility with FreeBSD 5.3, we pack the 37143769Sdas * mxcsr into some reserved fields, rather than changing sizeof(fenv_t). 38143769Sdas */ 39130144Sdastypedef struct { 40143769Sdas __uint16_t __control; 41143769Sdas __uint16_t __mxcsr_hi; 42143769Sdas __uint16_t __status; 43143769Sdas __uint16_t __mxcsr_lo; 44130144Sdas __uint32_t __tag; 45130144Sdas char __other[16]; 46130144Sdas} fenv_t; 47130144Sdas 48143769Sdas#define __get_mxcsr(env) (((env).__mxcsr_hi << 16) | \ 49143769Sdas ((env).__mxcsr_lo)) 50143769Sdas#define __set_mxcsr(env, x) do { \ 51143769Sdas (env).__mxcsr_hi = (__uint32_t)(x) >> 16; \ 52143769Sdas (env).__mxcsr_lo = (__uint16_t)(x); \ 53143769Sdas} while (0) 54143769Sdas 55130144Sdastypedef __uint16_t fexcept_t; 56130144Sdas 57130144Sdas/* Exception flags */ 58130144Sdas#define FE_INVALID 0x01 59130144Sdas#define FE_DENORMAL 0x02 60130144Sdas#define FE_DIVBYZERO 0x04 61130144Sdas#define FE_OVERFLOW 0x08 62130144Sdas#define FE_UNDERFLOW 0x10 63130144Sdas#define FE_INEXACT 0x20 64130144Sdas#define FE_ALL_EXCEPT (FE_DIVBYZERO | FE_DENORMAL | FE_INEXACT | \ 65130144Sdas FE_INVALID | FE_OVERFLOW | FE_UNDERFLOW) 66130144Sdas 67130144Sdas/* Rounding modes */ 68130144Sdas#define FE_TONEAREST 0x0000 69130144Sdas#define FE_DOWNWARD 0x0400 70130144Sdas#define FE_UPWARD 0x0800 71130144Sdas#define FE_TOWARDZERO 0x0c00 72130144Sdas#define _ROUND_MASK (FE_TONEAREST | FE_DOWNWARD | \ 73130144Sdas FE_UPWARD | FE_TOWARDZERO) 74130144Sdas 75143769Sdas/* 76143769Sdas * As compared to the x87 control word, the SSE unit's control word 77143769Sdas * has the rounding control bits offset by 3 and the exception mask 78143769Sdas * bits offset by 7. 79143769Sdas */ 80143769Sdas#define _SSE_ROUND_SHIFT 3 81143769Sdas#define _SSE_EMASK_SHIFT 7 82143769Sdas 83163358Sbde__BEGIN_DECLS 84163358Sbde 85143769Sdas/* After testing for SSE support once, we cache the result in __has_sse. */ 86143769Sdasenum __sse_support { __SSE_YES, __SSE_NO, __SSE_UNK }; 87143769Sdasextern enum __sse_support __has_sse; 88143769Sdasint __test_sse(void); 89143769Sdas#ifdef __SSE__ 90143769Sdas#define __HAS_SSE() 1 91143769Sdas#else 92143769Sdas#define __HAS_SSE() (__has_sse == __SSE_YES || \ 93143769Sdas (__has_sse == __SSE_UNK && __test_sse())) 94143769Sdas#endif 95143769Sdas 96130144Sdas/* Default floating-point environment */ 97130144Sdasextern const fenv_t __fe_dfl_env; 98130144Sdas#define FE_DFL_ENV (&__fe_dfl_env) 99130144Sdas 100130144Sdas#define __fldcw(__cw) __asm __volatile("fldcw %0" : : "m" (__cw)) 101130144Sdas#define __fldenv(__env) __asm __volatile("fldenv %0" : : "m" (__env)) 102165841Sdas#define __fldenvx(__env) __asm __volatile("fldenv %0" : : "m" (__env) \ 103165841Sdas : "st", "st(1)", "st(2)", "st(3)", "st(4)", \ 104165841Sdas "st(5)", "st(6)", "st(7)") 105130144Sdas#define __fnclex() __asm __volatile("fnclex") 106140219Sdas#define __fnstenv(__env) __asm __volatile("fnstenv %0" : "=m" (*(__env))) 107140219Sdas#define __fnstcw(__cw) __asm __volatile("fnstcw %0" : "=m" (*(__cw))) 108140219Sdas#define __fnstsw(__sw) __asm __volatile("fnstsw %0" : "=am" (*(__sw))) 109130144Sdas#define __fwait() __asm __volatile("fwait") 110143769Sdas#define __ldmxcsr(__csr) __asm __volatile("ldmxcsr %0" : : "m" (__csr)) 111143769Sdas#define __stmxcsr(__csr) __asm __volatile("stmxcsr %0" : "=m" (*(__csr))) 112130144Sdas 113130144Sdasstatic __inline int 114130144Sdasfeclearexcept(int __excepts) 115130144Sdas{ 116130144Sdas fenv_t __env; 117203441Skib __uint32_t __mxcsr; 118130144Sdas 119130144Sdas if (__excepts == FE_ALL_EXCEPT) { 120130144Sdas __fnclex(); 121130144Sdas } else { 122130144Sdas __fnstenv(&__env); 123130144Sdas __env.__status &= ~__excepts; 124130144Sdas __fldenv(__env); 125130144Sdas } 126143769Sdas if (__HAS_SSE()) { 127143769Sdas __stmxcsr(&__mxcsr); 128143769Sdas __mxcsr &= ~__excepts; 129143769Sdas __ldmxcsr(__mxcsr); 130143769Sdas } 131130144Sdas return (0); 132130144Sdas} 133130144Sdas 134130144Sdasstatic __inline int 135130144Sdasfegetexceptflag(fexcept_t *__flagp, int __excepts) 136130144Sdas{ 137203441Skib __uint32_t __mxcsr; 138203441Skib __uint16_t __status; 139130144Sdas 140130144Sdas __fnstsw(&__status); 141143769Sdas if (__HAS_SSE()) 142143769Sdas __stmxcsr(&__mxcsr); 143143769Sdas else 144143769Sdas __mxcsr = 0; 145143769Sdas *__flagp = (__mxcsr | __status) & __excepts; 146130144Sdas return (0); 147130144Sdas} 148130144Sdas 149143769Sdasint fesetexceptflag(const fexcept_t *__flagp, int __excepts); 150143769Sdasint feraiseexcept(int __excepts); 151130144Sdas 152130144Sdasstatic __inline int 153130144Sdasfetestexcept(int __excepts) 154130144Sdas{ 155203441Skib __uint32_t __mxcsr; 156203441Skib __uint16_t __status; 157130144Sdas 158130144Sdas __fnstsw(&__status); 159143769Sdas if (__HAS_SSE()) 160143769Sdas __stmxcsr(&__mxcsr); 161143769Sdas else 162143769Sdas __mxcsr = 0; 163143769Sdas return ((__status | __mxcsr) & __excepts); 164130144Sdas} 165130144Sdas 166130144Sdasstatic __inline int 167130144Sdasfegetround(void) 168130144Sdas{ 169203441Skib __uint16_t __control; 170130144Sdas 171143769Sdas /* 172143769Sdas * We assume that the x87 and the SSE unit agree on the 173143769Sdas * rounding mode. Reading the control word on the x87 turns 174143769Sdas * out to be about 5 times faster than reading it on the SSE 175143769Sdas * unit on an Opteron 244. 176143769Sdas */ 177130144Sdas __fnstcw(&__control); 178130144Sdas return (__control & _ROUND_MASK); 179130144Sdas} 180130144Sdas 181130144Sdasstatic __inline int 182130144Sdasfesetround(int __round) 183130144Sdas{ 184203441Skib __uint32_t __mxcsr; 185203441Skib __uint16_t __control; 186130144Sdas 187130144Sdas if (__round & ~_ROUND_MASK) 188130144Sdas return (-1); 189143769Sdas 190130144Sdas __fnstcw(&__control); 191130144Sdas __control &= ~_ROUND_MASK; 192130144Sdas __control |= __round; 193130144Sdas __fldcw(__control); 194130144Sdas 195143769Sdas if (__HAS_SSE()) { 196143769Sdas __stmxcsr(&__mxcsr); 197143769Sdas __mxcsr &= ~(_ROUND_MASK << _SSE_ROUND_SHIFT); 198143769Sdas __mxcsr |= __round << _SSE_ROUND_SHIFT; 199143769Sdas __ldmxcsr(__mxcsr); 200143769Sdas } 201130144Sdas 202130144Sdas return (0); 203130144Sdas} 204130144Sdas 205143769Sdasint fegetenv(fenv_t *__envp); 206143769Sdasint feholdexcept(fenv_t *__envp); 207130144Sdas 208130144Sdasstatic __inline int 209130144Sdasfesetenv(const fenv_t *__envp) 210130144Sdas{ 211143769Sdas fenv_t __env = *__envp; 212203441Skib __uint32_t __mxcsr; 213130144Sdas 214143769Sdas __mxcsr = __get_mxcsr(__env); 215143769Sdas __set_mxcsr(__env, 0xffffffff); 216165841Sdas /* 217165841Sdas * XXX Using fldenvx() instead of fldenv() tells the compiler that this 218165841Sdas * instruction clobbers the i387 register stack. This happens because 219165841Sdas * we restore the tag word from the saved environment. Normally, this 220165841Sdas * would happen anyway and we wouldn't care, because the ABI allows 221165841Sdas * function calls to clobber the i387 regs. However, fesetenv() is 222165841Sdas * inlined, so we need to be more careful. 223165841Sdas */ 224165841Sdas __fldenvx(__env); 225143769Sdas if (__HAS_SSE()) 226143769Sdas __ldmxcsr(__mxcsr); 227130144Sdas return (0); 228130144Sdas} 229130144Sdas 230143769Sdasint feupdateenv(const fenv_t *__envp); 231130144Sdas 232130144Sdas#if __BSD_VISIBLE 233130144Sdas 234143769Sdasint feenableexcept(int __mask); 235143769Sdasint fedisableexcept(int __mask); 236130144Sdas 237130144Sdasstatic __inline int 238143708Sdasfegetexcept(void) 239143708Sdas{ 240203441Skib __uint16_t __control; 241143708Sdas 242143769Sdas /* 243143769Sdas * We assume that the masks for the x87 and the SSE unit are 244143769Sdas * the same. 245143769Sdas */ 246143708Sdas __fnstcw(&__control); 247143708Sdas return (~__control & FE_ALL_EXCEPT); 248143708Sdas} 249143708Sdas 250130144Sdas#endif /* __BSD_VISIBLE */ 251130144Sdas 252130144Sdas__END_DECLS 253130144Sdas 254130144Sdas#endif /* !_FENV_H_ */ 255