/*- * 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 1.8 2011/10/10 15:43:09 das Exp $ */ #ifndef _FENV_H_ #define _FENV_H_ #include "include/cdefs-compat.h" #include "include/types-compat.h" #ifndef __fenv_static #define __fenv_static static #endif /* * 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 __BEGIN_DECLS /* 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 __has_sse; int __test_sse(void); #ifdef __SSE__ #define __HAS_SSE() 1 #else #define __HAS_SSE() (__has_sse == __SSE_YES || \ (__has_sse == __SSE_UNK && __test_sse())) #endif /* 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 __fldenvx(__env) __asm __volatile("fldenv %0" : : "m" (__env) \ : "st", "st(1)", "st(2)", "st(3)", "st(4)", \ "st(5)", "st(6)", "st(7)") #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))) __fenv_static inline int feclearexcept(int __excepts) { fenv_t __env; uint32_t __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); } __fenv_static inline int fegetexceptflag(fexcept_t *__flagp, int __excepts) { uint32_t __mxcsr; uint16_t __status; __fnstsw(&__status); if (__HAS_SSE()) __stmxcsr(&__mxcsr); else __mxcsr = 0; *__flagp = (__mxcsr | __status) & __excepts; return (0); } int fesetexceptflag(const fexcept_t *__flagp, int __excepts); int feraiseexcept(int __excepts); __fenv_static inline int fetestexcept(int __excepts) { uint32_t __mxcsr; uint16_t __status; __fnstsw(&__status); if (__HAS_SSE()) __stmxcsr(&__mxcsr); else __mxcsr = 0; return ((__status | __mxcsr) & __excepts); } __fenv_static inline int fegetround(void) { uint16_t __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); } __fenv_static inline int fesetround(int __round) { uint32_t __mxcsr; uint16_t __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 fegetenv(fenv_t *__envp); int feholdexcept(fenv_t *__envp); __fenv_static inline int fesetenv(const fenv_t *__envp) { fenv_t __env = *__envp; uint32_t __mxcsr; __mxcsr = __get_mxcsr(__env); __set_mxcsr(__env, 0xffffffff); /* * XXX Using fldenvx() instead of fldenv() tells the compiler that this * instruction clobbers the i387 register stack. This happens because * we restore the tag word from the saved environment. Normally, this * would happen anyway and we wouldn't care, because the ABI allows * function calls to clobber the i387 regs. However, fesetenv() is * inlined, so we need to be more careful. */ __fldenvx(__env); if (__HAS_SSE()) __ldmxcsr(__mxcsr); return (0); } int feupdateenv(const fenv_t *__envp); #if __BSD_VISIBLE int feenableexcept(int __mask); int fedisableexcept(int __mask); /* We currently provide no external definition of fegetexcept(). */ static inline int fegetexcept(void) { uint16_t __control; /* * We assume that the masks for the x87 and the SSE unit are * the same. */ __fnstcw(&__control); return (~__control & FE_ALL_EXCEPT); } #endif /* __BSD_VISIBLE */ __END_DECLS #endif /* !_FENV_H_ */