1/* mpz_set_d(integer, val) -- Assign INTEGER with a double value VAL. 2 3Copyright 1995, 1996, 2000-2003, 2006, 2015 Free Software Foundation, Inc. 4 5This file is part of the GNU MP Library. 6 7The GNU MP Library is free software; you can redistribute it and/or modify 8it under the terms of either: 9 10 * the GNU Lesser General Public License as published by the Free 11 Software Foundation; either version 3 of the License, or (at your 12 option) any later version. 13 14or 15 16 * the GNU General Public License as published by the Free Software 17 Foundation; either version 2 of the License, or (at your option) any 18 later version. 19 20or both in parallel, as here. 21 22The GNU MP Library is distributed in the hope that it will be useful, but 23WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 24or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 25for more details. 26 27You should have received copies of the GNU General Public License and the 28GNU Lesser General Public License along with the GNU MP Library. If not, 29see https://www.gnu.org/licenses/. */ 30 31#include "config.h" 32 33#if HAVE_FLOAT_H 34#include <float.h> /* for DBL_MAX */ 35#endif 36 37#include "gmp-impl.h" 38 39 40/* We used to have a special case for d < MP_BASE_AS_DOUBLE, just casting 41 double -> limb. Unfortunately gcc 3.3 on powerpc970-apple-darwin6.8.5 42 got this wrong. (It assumed __fixunsdfdi returned its result in a single 43 64-bit register, where instead that function followed the calling 44 conventions and gave the result in two parts r3 and r4.) Hence the use 45 of __gmp_extract_double in all cases. */ 46 47void 48mpz_set_d (mpz_ptr r, double d) 49{ 50 int negative; 51 mp_limb_t tp[LIMBS_PER_DOUBLE]; 52 mp_ptr rp; 53 mp_size_t rn; 54 55 DOUBLE_NAN_INF_ACTION (d, 56 __gmp_invalid_operation (), 57 __gmp_invalid_operation ()); 58 59 negative = d < 0; 60 d = ABS (d); 61 62 rn = __gmp_extract_double (tp, d); 63 64 if (rn <= 0) 65 rn = 0; 66 67 rp = MPZ_NEWALLOC (r, rn); 68 69 switch (rn) 70 { 71 default: 72 MPN_ZERO (rp, rn - LIMBS_PER_DOUBLE); 73 rp += rn - LIMBS_PER_DOUBLE; 74 /* fall through */ 75#if LIMBS_PER_DOUBLE == 2 76 case 2: 77 rp[1] = tp[1], rp[0] = tp[0]; 78 break; 79 case 1: 80 rp[0] = tp[1]; 81 break; 82#endif 83#if LIMBS_PER_DOUBLE == 3 84 case 3: 85 rp[2] = tp[2], rp[1] = tp[1], rp[0] = tp[0]; 86 break; 87 case 2: 88 rp[1] = tp[2], rp[0] = tp[1]; 89 break; 90 case 1: 91 rp[0] = tp[2]; 92 break; 93#endif 94#if LIMBS_PER_DOUBLE == 4 95 case 4: 96 rp[3] = tp[3], rp[2] = tp[2], rp[1] = tp[1], rp[0] = tp[0]; 97 break; 98 case 3: 99 rp[2] = tp[3], rp[1] = tp[2], rp[0] = tp[1]; 100 break; 101 case 2: 102 rp[1] = tp[3], rp[0] = tp[2]; 103 break; 104 case 1: 105 rp[0] = tp[3]; 106 break; 107#endif 108 case 0: 109 break; 110 } 111 112 SIZ(r) = negative ? -rn : rn; 113} 114