1/* Conversion routines from GCC internal float representation to MPFR. 2 Copyright (C) 2010-2015 Free Software Foundation, Inc. 3 4 This file is part of GCC. 5 6 GCC is free software; you can redistribute it and/or modify it under 7 the terms of the GNU General Public License as published by the Free 8 Software Foundation; either version 3, or (at your option) any later 9 version. 10 11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY 12 WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with GCC; see the file COPYING3. If not see 18 <http://www.gnu.org/licenses/>. */ 19 20#include "config.h" 21#include "system.h" 22#include "coretypes.h" 23#include "realmpfr.h" 24#include "hash-set.h" 25#include "machmode.h" 26#include "vec.h" 27#include "double-int.h" 28#include "input.h" 29#include "alias.h" 30#include "symtab.h" 31#include "options.h" 32#include "wide-int.h" 33#include "inchash.h" 34#include "tree.h" /* For TYPE_MODE in real_from_mpfr. */ 35#include "stor-layout.h" 36 37/* Convert from REAL_VALUE_TYPE to MPFR. The caller is responsible 38 for initializing and clearing the MPFR parameter. */ 39 40void 41mpfr_from_real (mpfr_ptr m, const REAL_VALUE_TYPE *r, mp_rnd_t rndmode) 42{ 43 /* We use a string as an intermediate type. */ 44 char buf[128]; 45 int ret; 46 47 /* Take care of Infinity and NaN. */ 48 if (r->cl == rvc_inf) 49 { 50 mpfr_set_inf (m, r->sign == 1 ? -1 : 1); 51 return; 52 } 53 54 if (r->cl == rvc_nan) 55 { 56 mpfr_set_nan (m); 57 return; 58 } 59 60 real_to_hexadecimal (buf, r, sizeof (buf), 0, 1); 61 /* mpfr_set_str() parses hexadecimal floats from strings in the same 62 format that GCC will output them. Nothing extra is needed. */ 63 ret = mpfr_set_str (m, buf, 16, rndmode); 64 gcc_assert (ret == 0); 65} 66 67/* Convert from MPFR to REAL_VALUE_TYPE, for a given type TYPE and rounding 68 mode RNDMODE. TYPE is only relevant if M is a NaN. */ 69 70void 71real_from_mpfr (REAL_VALUE_TYPE *r, mpfr_srcptr m, tree type, mp_rnd_t rndmode) 72{ 73 /* We use a string as an intermediate type. */ 74 char buf[128], *rstr; 75 mp_exp_t exp; 76 77 /* Take care of Infinity and NaN. */ 78 if (mpfr_inf_p (m)) 79 { 80 real_inf (r); 81 if (mpfr_sgn (m) < 0) 82 *r = real_value_negate (r); 83 return; 84 } 85 86 if (mpfr_nan_p (m)) 87 { 88 real_nan (r, "", 1, TYPE_MODE (type)); 89 return; 90 } 91 92 rstr = mpfr_get_str (NULL, &exp, 16, 0, m, rndmode); 93 94 /* The additional 12 chars add space for the sprintf below. This 95 leaves 6 digits for the exponent which is supposedly enough. */ 96 gcc_assert (rstr != NULL && strlen (rstr) < sizeof (buf) - 12); 97 98 /* REAL_VALUE_ATOF expects the exponent for mantissa * 2**exp, 99 mpfr_get_str returns the exponent for mantissa * 16**exp, adjust 100 for that. */ 101 exp *= 4; 102 103 if (rstr[0] == '-') 104 sprintf (buf, "-0x.%sp%d", &rstr[1], (int) exp); 105 else 106 sprintf (buf, "0x.%sp%d", rstr, (int) exp); 107 108 mpfr_free_str (rstr); 109 110 real_from_string (r, buf); 111} 112 113