1 /* Conversion routines from GCC internal float representation to MPFR. 2 Copyright (C) 2010-2018 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 "tree.h" 24 #include "realmpfr.h" 25 #include "stor-layout.h" 26 27 /* Convert from REAL_VALUE_TYPE to MPFR. The caller is responsible 28 for initializing and clearing the MPFR parameter. */ 29 30 void 31 mpfr_from_real (mpfr_ptr m, const REAL_VALUE_TYPE *r, mp_rnd_t rndmode) 32 { 33 /* We use a string as an intermediate type. */ 34 char buf[128]; 35 int ret; 36 37 /* Take care of Infinity and NaN. */ 38 if (r->cl == rvc_inf) 39 { 40 mpfr_set_inf (m, r->sign == 1 ? -1 : 1); 41 return; 42 } 43 44 if (r->cl == rvc_nan) 45 { 46 mpfr_set_nan (m); 47 return; 48 } 49 50 real_to_hexadecimal (buf, r, sizeof (buf), 0, 1); 51 /* mpfr_set_str() parses hexadecimal floats from strings in the same 52 format that GCC will output them. Nothing extra is needed. */ 53 ret = mpfr_set_str (m, buf, 16, rndmode); 54 gcc_assert (ret == 0); 55 } 56 57 /* Convert from MPFR to REAL_VALUE_TYPE, for a given format FORMAT and 58 rounding mode RNDMODE. FORMAT is only relevant if M is a NaN. */ 59 60 void 61 real_from_mpfr (REAL_VALUE_TYPE *r, mpfr_srcptr m, const real_format *format, 62 mp_rnd_t rndmode) 63 { 64 /* We use a string as an intermediate type. */ 65 char buf[128], *rstr; 66 mp_exp_t exp; 67 68 /* Take care of Infinity and NaN. */ 69 if (mpfr_inf_p (m)) 70 { 71 real_inf (r); 72 if (mpfr_sgn (m) < 0) 73 *r = real_value_negate (r); 74 return; 75 } 76 77 if (mpfr_nan_p (m)) 78 { 79 real_nan (r, "", 1, format); 80 return; 81 } 82 83 rstr = mpfr_get_str (NULL, &exp, 16, 0, m, rndmode); 84 85 /* The additional 12 chars add space for the sprintf below. This 86 leaves 6 digits for the exponent which is supposedly enough. */ 87 gcc_assert (rstr != NULL && strlen (rstr) < sizeof (buf) - 12); 88 89 /* REAL_VALUE_ATOF expects the exponent for mantissa * 2**exp, 90 mpfr_get_str returns the exponent for mantissa * 16**exp, adjust 91 for that. */ 92 exp *= 4; 93 94 if (rstr[0] == '-') 95 sprintf (buf, "-0x.%sp%d", &rstr[1], (int) exp); 96 else 97 sprintf (buf, "0x.%sp%d", rstr, (int) exp); 98 99 mpfr_free_str (rstr); 100 101 real_from_string (r, buf); 102 } 103 104 /* Convert from MPFR to REAL_VALUE_TYPE, for a given type TYPE and rounding 105 mode RNDMODE. TYPE is only relevant if M is a NaN. */ 106 107 void 108 real_from_mpfr (REAL_VALUE_TYPE *r, mpfr_srcptr m, tree type, mp_rnd_t rndmode) 109 { 110 real_from_mpfr (r, m, type ? REAL_MODE_FORMAT (TYPE_MODE (type)) : NULL, 111 rndmode); 112 } 113 114