/** @file * IPRT / No-CRT - fenv.h, X86. */ /* * Copyright (C) 2006-2019 Oracle Corporation * * This file is part of VirtualBox Open Source Edition (OSE), as * available from http://www.virtualbox.org. This file is free software; * you can redistribute it and/or modify it under the terms of the GNU * General Public License (GPL) as published by the Free Software * Foundation, in version 2 as it comes in the "COPYING" file of the * VirtualBox OSE distribution. VirtualBox OSE is distributed in the * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind. * * The contents of this file may alternatively be used under the terms * of the Common Development and Distribution License Version 1.0 * (CDDL) only, as it comes in the "COPYING.CDDL" file of the * VirtualBox OSE distribution, in which case the provisions of the * CDDL are applicable instead of those of the GPL. * * You may elect to license modified versions of this file under the * terms and conditions of either the GPL or the CDDL or both. * -------------------------------------------------------------------- * * This code is based on: * * Copyright (c) 2004-2005 David Schultz * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * $FreeBSD: src/lib/msun/i387/fenv.h,v 1.4 2005/03/17 22:21:46 das Exp $ */ #ifndef IPRT_INCLUDED_nocrt_x86_fenv_h #define IPRT_INCLUDED_nocrt_x86_fenv_h #ifndef RT_WITHOUT_PRAGMA_ONCE # pragma once #endif #include /* * To preserve binary compatibility with FreeBSD 5.3, we pack the * mxcsr into some reserved fields, rather than changing sizeof(fenv_t). */ typedef struct { uint16_t __control; uint16_t __mxcsr_hi; uint16_t __status; uint16_t __mxcsr_lo; uint32_t __tag; char __other[16]; } fenv_t; #define __get_mxcsr(env) (((env).__mxcsr_hi << 16) | \ ((env).__mxcsr_lo)) #define __set_mxcsr(env, x) do { \ (env).__mxcsr_hi = (uint32_t)(x) >> 16; \ (env).__mxcsr_lo = (uint16_t)(x); \ } while (0) typedef uint16_t fexcept_t; /* Exception flags */ #define FE_INVALID 0x01 #define FE_DENORMAL 0x02 #define FE_DIVBYZERO 0x04 #define FE_OVERFLOW 0x08 #define FE_UNDERFLOW 0x10 #define FE_INEXACT 0x20 #define FE_ALL_EXCEPT (FE_DIVBYZERO | FE_DENORMAL | FE_INEXACT | \ FE_INVALID | FE_OVERFLOW | FE_UNDERFLOW) /* Rounding modes */ #define FE_TONEAREST 0x0000 #define FE_DOWNWARD 0x0400 #define FE_UPWARD 0x0800 #define FE_TOWARDZERO 0x0c00 #define _ROUND_MASK (FE_TONEAREST | FE_DOWNWARD | \ FE_UPWARD | FE_TOWARDZERO) /* * As compared to the x87 control word, the SSE unit's control word * has the rounding control bits offset by 3 and the exception mask * bits offset by 7. */ #define _SSE_ROUND_SHIFT 3 #define _SSE_EMASK_SHIFT 7 /* After testing for SSE support once, we cache the result in __has_sse. */ enum __sse_support { __SSE_YES, __SSE_NO, __SSE_UNK }; extern enum __sse_support RT_NOCRT(__has_sse); int RT_NOCRT(__test_sse)(void); #ifdef __SSE__ #define __HAS_SSE() 1 #else #define __HAS_SSE() (RT_NOCRT(__has_sse) == __SSE_YES || \ (RT_NOCRT(__has_sse) == __SSE_UNK && RT_NOCRT(__test_sse)())) #endif RT_C_DECLS_BEGIN /* Default floating-point environment */ extern const fenv_t __fe_dfl_env; #define FE_DFL_ENV (&__fe_dfl_env) #define __fldcw(__cw) __asm __volatile("fldcw %0" : : "m" (__cw)) #define __fldenv(__env) __asm __volatile("fldenv %0" : : "m" (__env)) #define __fnclex() __asm __volatile("fnclex") #define __fnstenv(__env) __asm __volatile("fnstenv %0" : "=m" (*(__env))) #define __fnstcw(__cw) __asm __volatile("fnstcw %0" : "=m" (*(__cw))) #define __fnstsw(__sw) __asm __volatile("fnstsw %0" : "=am" (*(__sw))) #define __fwait() __asm __volatile("fwait") #define __ldmxcsr(__csr) __asm __volatile("ldmxcsr %0" : : "m" (__csr)) #define __stmxcsr(__csr) __asm __volatile("stmxcsr %0" : "=m" (*(__csr))) #if RT_GNUC_PREREQ(4, 6) # pragma GCC diagnostic push # pragma GCC diagnostic ignored "-Wshadow" #endif DECLINLINE(int) feclearexcept(int __excepts) { fenv_t __env; int __mxcsr; if (__excepts == FE_ALL_EXCEPT) { __fnclex(); } else { __fnstenv(&__env); __env.__status &= ~__excepts; __fldenv(__env); } if (__HAS_SSE()) { __stmxcsr(&__mxcsr); __mxcsr &= ~__excepts; __ldmxcsr(__mxcsr); } return (0); } DECLINLINE(int) fegetexceptflag(fexcept_t *__flagp, int __excepts) { int __mxcsr, __status; __fnstsw(&__status); if (__HAS_SSE()) __stmxcsr(&__mxcsr); else __mxcsr = 0; *__flagp = (__mxcsr | __status) & __excepts; return (0); } int RT_NOCRT(fesetexceptflag)(const fexcept_t *__flagp, int __excepts); int RT_NOCRT(feraiseexcept)(int __excepts); DECLINLINE(int) fetestexcept(int __excepts) { int __mxcsr, __status; __fnstsw(&__status); if (__HAS_SSE()) __stmxcsr(&__mxcsr); else __mxcsr = 0; return ((__status | __mxcsr) & __excepts); } DECLINLINE(int) fegetround(void) { int __control; /* * We assume that the x87 and the SSE unit agree on the * rounding mode. Reading the control word on the x87 turns * out to be about 5 times faster than reading it on the SSE * unit on an Opteron 244. */ __fnstcw(&__control); return (__control & _ROUND_MASK); } DECLINLINE(int) fesetround(int __round) { int __mxcsr, __control; if (__round & ~_ROUND_MASK) return (-1); __fnstcw(&__control); __control &= ~_ROUND_MASK; __control |= __round; __fldcw(__control); if (__HAS_SSE()) { __stmxcsr(&__mxcsr); __mxcsr &= ~(_ROUND_MASK << _SSE_ROUND_SHIFT); __mxcsr |= __round << _SSE_ROUND_SHIFT; __ldmxcsr(__mxcsr); } return (0); } int RT_NOCRT(fegetenv)(fenv_t *__envp); int RT_NOCRT(feholdexcept)(fenv_t *__envp); DECLINLINE(int) fesetenv(const fenv_t *__envp) { fenv_t __env = *__envp; int __mxcsr; __mxcsr = __get_mxcsr(__env); __set_mxcsr(__env, 0xffffffff); __fldenv(__env); if (__HAS_SSE()) __ldmxcsr(__mxcsr); return (0); } int RT_NOCRT(feupdateenv)(const fenv_t *__envp); int RT_NOCRT(feenableexcept)(int __mask); int RT_NOCRT(fedisableexcept)(int __mask); DECLINLINE(int) fegetexcept(void) { int __control; /* * We assume that the masks for the x87 and the SSE unit are * the same. */ __fnstcw(&__control); return (~__control & FE_ALL_EXCEPT); } #if RT_GNUC_PREREQ(4, 6) # pragma GCC diagnostic pop #endif RT_C_DECLS_END #ifndef RT_WIHTOUT_NOCRT_WRAPPERS # define __has_sse RT_NOCRT(__has_sse) # define __test_sse RT_NOCRT(__test_sse) # define __test_sse RT_NOCRT(__test_sse) # define fesetexceptflag RT_NOCRT(fesetexceptflag) # define feraiseexcept RT_NOCRT(feraiseexcept) # define fegetenv RT_NOCRT(fegetenv) # define feholdexcept RT_NOCRT(feholdexcept) # define feupdateenv RT_NOCRT(feupdateenv) # define feenableexcept RT_NOCRT(feenableexcept) # define fedisableexcept RT_NOCRT(fedisableexcept) #endif #endif /* !IPRT_INCLUDED_nocrt_x86_fenv_h */