From 6c9b0f68267cf365d060d4e51e7cb8f61498b875 Mon Sep 17 00:00:00 2001 From: Joseph Myers Date: Wed, 12 Sep 2012 23:36:19 +0000 Subject: Make strtod respect the rounding mode (bug 14518). --- sysdeps/generic/get-rounding-mode.h | 124 ++++++++++++++++++++++++++++++++++++ 1 file changed, 124 insertions(+) create mode 100644 sysdeps/generic/get-rounding-mode.h (limited to 'sysdeps/generic') diff --git a/sysdeps/generic/get-rounding-mode.h b/sysdeps/generic/get-rounding-mode.h new file mode 100644 index 0000000000..0ecaddd7bf --- /dev/null +++ b/sysdeps/generic/get-rounding-mode.h @@ -0,0 +1,124 @@ +/* Determine floating-point rounding mode within libc. Generic version. + Copyright (C) 2012 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#ifndef _GET_ROUNDING_MODE_H +#define _GET_ROUNDING_MODE_H 1 + +#include + +/* Define values for FE_* modes not defined for this architecture. */ +#ifdef FE_DOWNWARD +# define ORIG_FE_DOWNWARD FE_DOWNWARD +#else +# define ORIG_FE_DOWNWARD 0 +#endif +#ifdef FE_TONEAREST +# define ORIG_FE_TONEAREST FE_TONEAREST +#else +# define ORIG_FE_TONEAREST 0 +#endif +#ifdef FE_TOWARDZERO +# define ORIG_FE_TOWARDZERO FE_TOWARDZERO +#else +# define ORIG_FE_TOWARDZERO 0 +#endif +#ifdef FE_UPWARD +# define ORIG_FE_UPWARD FE_UPWARD +#else +# define ORIG_FE_UPWARD 0 +#endif +#define FE_CONSTRUCT_DISTINCT_VALUE(X, Y, Z) \ + ((((X) & 1) | ((Y) & 2) | ((Z) & 4)) ^ 7) +#ifndef FE_DOWNWARD +# define FE_DOWNWARD FE_CONSTRUCT_DISTINCT_VALUE (ORIG_FE_TONEAREST, \ + ORIG_FE_TOWARDZERO, \ + ORIG_FE_UPWARD) +#endif +#ifndef FE_TONEAREST +# define FE_TONEAREST FE_CONSTRUCT_DISTINCT_VALUE (FE_DOWNWARD, \ + ORIG_FE_TOWARDZERO, \ + ORIG_FE_UPWARD) +#endif +#ifndef FE_TOWARDZERO +# define FE_TOWARDZERO FE_CONSTRUCT_DISTINCT_VALUE (FE_DOWNWARD, \ + FE_TONEAREST, \ + ORIG_FE_UPWARD) +#endif +#ifndef FE_UPWARD +# define FE_UPWARD FE_CONSTRUCT_DISTINCT_VALUE (FE_DOWNWARD, \ + FE_TONEAREST, \ + FE_TOWARDZERO) +#endif + +/* Return the floating-point rounding mode. */ + +static inline int +get_rounding_mode (void) +{ +#if (defined _FPU_RC_DOWN \ + || defined _FPU_RC_NEAREST \ + || defined _FPU_RC_ZERO \ + || defined _FPU_RC_UP) + fpu_control_t fc; + const fpu_control_t mask = (0 +# ifdef _FPU_RC_DOWN + | _FPU_RC_DOWN +# endif +# ifdef _FPU_RC_NEAREST + | _FPU_RC_NEAREST +# endif +# ifdef _FPU_RC_ZERO + | _FPU_RC_ZERO +# endif +# ifdef _FPU_RC_UP + | _FPU_RC_UP +# endif + ); + + _FPU_GETCW (fc); + switch (fc & mask) + { +# ifdef _FPU_RC_DOWN + case _FPU_RC_DOWN: + return FE_DOWNWARD; +# endif + +# ifdef _FPU_RC_NEAREST + case _FPU_RC_NEAREST: + return FE_TONEAREST; +# endif + +# ifdef _FPU_RC_ZERO + case _FPU_RC_ZERO: + return FE_TOWARDZERO; +# endif + +# ifdef _FPU_RC_UP + case _FPU_RC_UP: + return FE_UPWARD; +# endif + + default: + abort (); + } +#else + return FE_TONEAREST; +#endif +} + +#endif /* get-rounding-mode.h */ -- cgit 1.4.1