1 /* $NetBSD: strtoIg.c,v 1.1.1.1 2006/01/25 15:18:50 kleink 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_Inexact)) { 51 B[1] = 0; 52 return *rvp = rv; 53 } 54 e1 = exp[0]; 55 rv1 = rv ^ STRTOG_Inexact; 56 b1 = Balloc(b->k); 57 Bcopy(b1, b); 58 nb = fpi->nbits; 59 nb1 = nb & 31; 60 nb11 = (nb1 - 1) & 31; 61 nw = b->wds; 62 nw1 = nw - 1; 63 if (rv & STRTOG_Inexlo) { 64 swap = 0; 65 b1 = increment(b1); 66 if (fpi->sudden_underflow 67 && (rv & STRTOG_Retmask) == STRTOG_Zero) { 68 b1->x[0] = 0; 69 b1->x[nw1] = 1L << nb11; 70 rv1 += STRTOG_Normal - STRTOG_Zero; 71 rv1 &= ~STRTOG_Underflow; 72 goto swapcheck; 73 } 74 if (b1->wds > nw 75 || nb1 && b1->x[nw1] & 1L << nb1) { 76 if (++e1 > fpi->emax) 77 rv1 = STRTOG_Infinite | STRTOG_Inexhi; 78 rshift(b1, 1); 79 } 80 else if ((rv & STRTOG_Retmask) == STRTOG_Denormal) { 81 if (b1->x[nw1] & 1L << nb11) { 82 rv1 += STRTOG_Normal - STRTOG_Denormal; 83 rv1 &= ~STRTOG_Underflow; 84 } 85 } 86 } 87 else { 88 swap = STRTOG_Neg; 89 if ((rv & STRTOG_Retmask) == STRTOG_Infinite) { 90 b1 = set_ones(b1, nb); 91 e1 = fpi->emax; 92 rv1 = STRTOG_Normal | STRTOG_Inexlo; 93 goto swapcheck; 94 } 95 decrement(b1); 96 if ((rv & STRTOG_Retmask) == STRTOG_Denormal) { 97 for(i = nw1; !b1->x[i]; --i) 98 if (!i) { 99 rv1 = STRTOG_Zero | STRTOG_Inexlo; 100 break; 101 } 102 goto swapcheck; 103 } 104 if (!(b1->x[nw1] & 1L << nb11)) { 105 if (e1 == fpi->emin) { 106 if (fpi->sudden_underflow) 107 rv1 += STRTOG_Zero - STRTOG_Normal; 108 else 109 rv1 += STRTOG_Denormal - STRTOG_Normal; 110 rv1 |= STRTOG_Underflow; 111 } 112 else { 113 b1 = lshift(b1, 1); 114 b1->x[0] |= 1; 115 --e1; 116 } 117 } 118 } 119 swapcheck: 120 if (swap ^ (rv & STRTOG_Neg)) { 121 rvp[0] = rv1; 122 rvp[1] = rv; 123 B[0] = b1; 124 B[1] = b; 125 exp[1] = exp[0]; 126 exp[0] = e1; 127 } 128 else { 129 rvp[0] = rv; 130 rvp[1] = rv1; 131 B[1] = b1; 132 exp[1] = e1; 133 } 134 return rv; 135 } 136