1 /* $NetBSD: strtoIg.c,v 1.2 2008/03/21 23:13:48 christos Exp $ */ 2 3 /**************************************************************** 4 5 The author of this software is David M. Gay. 6 7 Copyright (C) 1998 by Lucent Technologies 8 All Rights Reserved 9 10 Permission to use, copy, modify, and distribute this software and 11 its documentation for any purpose and without fee is hereby 12 granted, provided that the above copyright notice appear in all 13 copies and that both that the copyright notice and this 14 permission notice and warranty disclaimer appear in supporting 15 documentation, and that the name of Lucent or any of its entities 16 not be used in advertising or publicity pertaining to 17 distribution of the software without specific, written prior 18 permission. 19 20 LUCENT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, 21 INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. 22 IN NO EVENT SHALL LUCENT OR ANY OF ITS ENTITIES BE LIABLE FOR ANY 23 SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 24 WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER 25 IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, 26 ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF 27 THIS SOFTWARE. 28 29 ****************************************************************/ 30 31 /* Please send bug reports to David M. Gay (dmg at acm dot org, 32 * with " at " changed at "@" and " dot " changed to "."). */ 33 34 #include "gdtoaimp.h" 35 36 int 37 #ifdef KR_headers 38 strtoIg(s00, se, fpi, exp, B, rvp) CONST char *s00; char **se; FPI *fpi; Long *exp; Bigint **B; int *rvp; 39 #else 40 strtoIg(CONST char *s00, char **se, FPI *fpi, Long *exp, Bigint **B, int *rvp) 41 #endif 42 { 43 Bigint *b, *b1; 44 int i, nb, nw, nw1, rv, rv1, swap; 45 unsigned int nb1, nb11; 46 Long e1; 47 48 b = *B; 49 rv = strtodg(s00, se, fpi, exp, b->x); 50 if (rv == STRTOG_NoMemory) 51 return rv; 52 if (!(rv & STRTOG_Inexact)) { 53 B[1] = 0; 54 return *rvp = rv; 55 } 56 e1 = exp[0]; 57 rv1 = rv ^ STRTOG_Inexact; 58 b1 = Balloc(b->k); 59 if (b1 == NULL) 60 return STRTOG_NoMemory; 61 Bcopy(b1, b); 62 nb = fpi->nbits; 63 nb1 = nb & 31; 64 nb11 = (nb1 - 1) & 31; 65 nw = b->wds; 66 nw1 = nw - 1; 67 if (rv & STRTOG_Inexlo) { 68 swap = 0; 69 b1 = increment(b1); 70 if (fpi->sudden_underflow 71 && (rv & STRTOG_Retmask) == STRTOG_Zero) { 72 b1->x[0] = 0; 73 b1->x[nw1] = 1L << nb11; 74 rv1 += STRTOG_Normal - STRTOG_Zero; 75 rv1 &= ~STRTOG_Underflow; 76 goto swapcheck; 77 } 78 if (b1->wds > nw 79 || nb1 && b1->x[nw1] & 1L << nb1) { 80 if (++e1 > fpi->emax) 81 rv1 = STRTOG_Infinite | STRTOG_Inexhi; 82 rshift(b1, 1); 83 } 84 else if ((rv & STRTOG_Retmask) == STRTOG_Denormal) { 85 if (b1->x[nw1] & 1L << nb11) { 86 rv1 += STRTOG_Normal - STRTOG_Denormal; 87 rv1 &= ~STRTOG_Underflow; 88 } 89 } 90 } 91 else { 92 swap = STRTOG_Neg; 93 if ((rv & STRTOG_Retmask) == STRTOG_Infinite) { 94 b1 = set_ones(b1, nb); 95 e1 = fpi->emax; 96 rv1 = STRTOG_Normal | STRTOG_Inexlo; 97 goto swapcheck; 98 } 99 decrement(b1); 100 if ((rv & STRTOG_Retmask) == STRTOG_Denormal) { 101 for(i = nw1; !b1->x[i]; --i) 102 if (!i) { 103 rv1 = STRTOG_Zero | STRTOG_Inexlo; 104 break; 105 } 106 goto swapcheck; 107 } 108 if (!(b1->x[nw1] & 1L << nb11)) { 109 if (e1 == fpi->emin) { 110 if (fpi->sudden_underflow) 111 rv1 += STRTOG_Zero - STRTOG_Normal; 112 else 113 rv1 += STRTOG_Denormal - STRTOG_Normal; 114 rv1 |= STRTOG_Underflow; 115 } 116 else { 117 b1 = lshift(b1, 1); 118 b1->x[0] |= 1; 119 --e1; 120 } 121 } 122 } 123 swapcheck: 124 if (swap ^ (rv & STRTOG_Neg)) { 125 rvp[0] = rv1; 126 rvp[1] = rv; 127 B[0] = b1; 128 B[1] = b; 129 exp[1] = exp[0]; 130 exp[0] = e1; 131 } 132 else { 133 rvp[0] = rv; 134 rvp[1] = rv1; 135 B[1] = b1; 136 exp[1] = e1; 137 } 138 return rv; 139 } 140