1 /**************************************************************** 2 3 The author of this software is David M. Gay. 4 5 Copyright (C) 1998, 2000 by Lucent Technologies 6 All Rights Reserved 7 8 Permission to use, copy, modify, and distribute this software and 9 its documentation for any purpose and without fee is hereby 10 granted, provided that the above copyright notice appear in all 11 copies and that both that the copyright notice and this 12 permission notice and warranty disclaimer appear in supporting 13 documentation, and that the name of Lucent or any of its entities 14 not be used in advertising or publicity pertaining to 15 distribution of the software without specific, written prior 16 permission. 17 18 LUCENT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, 19 INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. 20 IN NO EVENT SHALL LUCENT OR ANY OF ITS ENTITIES BE LIABLE FOR ANY 21 SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 22 WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER 23 IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, 24 ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF 25 THIS SOFTWARE. 26 27 ****************************************************************/ 28 29 /* Please send bug reports to David M. Gay (dmg at acm dot org, 30 * with " at " changed at "@" and " dot " changed to "."). */ 31 32 #include "gdtoaimp.h" 33 34 int 35 #ifdef KR_headers 36 strtopdd(s, sp, dd) CONST char *s; char **sp; double *dd; 37 #else 38 strtopdd(CONST char *s, char **sp, double *dd) 39 #endif 40 { 41 #ifdef Sudden_Underflow 42 static FPI fpi0 = { 106, 1-1023, 2046-1023-106+1, 1, 1 }; 43 #else 44 static FPI fpi0 = { 106, 1-1023-53+1, 2046-1023-106+1, 1, 0 }; 45 #endif 46 ULong bits[4]; 47 Long exp; 48 int i, j, rv; 49 typedef union { 50 double d[2]; 51 ULong L[4]; 52 } U; 53 U *u; 54 #ifdef Honor_FLT_ROUNDS 55 #include "gdtoa_fltrnds.h" 56 #else 57 #define fpi &fpi0 58 #endif 59 60 rv = strtodg(s, sp, fpi, &exp, bits); 61 u = (U*)dd; 62 switch(rv & STRTOG_Retmask) { 63 case STRTOG_NoNumber: 64 case STRTOG_Zero: 65 u->d[0] = u->d[1] = 0.; 66 break; 67 68 case STRTOG_Normal: 69 u->L[_1] = (bits[1] >> 21 | bits[2] << 11) & 0xffffffffL; 70 u->L[_0] = (bits[2] >> 21) | ((bits[3] << 11) & 0xfffff) 71 | ((exp + 0x3ff + 105) << 20); 72 exp += 0x3ff + 52; 73 if (bits[1] &= 0x1fffff) { 74 i = hi0bits(bits[1]) - 11; 75 if (i >= exp) { 76 i = exp - 1; 77 exp = 0; 78 } 79 else 80 exp -= i; 81 if (i > 0) { 82 bits[1] = bits[1] << i | bits[0] >> (32-i); 83 bits[0] = bits[0] << i & 0xffffffffL; 84 } 85 } 86 else if (bits[0]) { 87 i = hi0bits(bits[0]) + 21; 88 if (i >= exp) { 89 i = exp - 1; 90 exp = 0; 91 } 92 else 93 exp -= i; 94 if (i < 32) { 95 bits[1] = bits[0] >> (32 - i); 96 bits[0] = bits[0] << i & 0xffffffffL; 97 } 98 else { 99 bits[1] = bits[0] << (i - 32); 100 bits[0] = 0; 101 } 102 } 103 else { 104 u->L[2] = u->L[3] = 0; 105 break; 106 } 107 u->L[2+_1] = bits[0]; 108 u->L[2+_0] = (bits[1] & 0xfffff) | (exp << 20); 109 break; 110 111 case STRTOG_Denormal: 112 if (bits[3]) 113 goto nearly_normal; 114 if (bits[2]) 115 goto partly_normal; 116 if (bits[1] & 0xffe00000) 117 goto hardly_normal; 118 /* completely denormal */ 119 u->L[2] = u->L[3] = 0; 120 u->L[_1] = bits[0]; 121 u->L[_0] = bits[1]; 122 break; 123 124 nearly_normal: 125 i = hi0bits(bits[3]) - 11; /* i >= 12 */ 126 j = 32 - i; 127 u->L[_0] = ((bits[3] << i | bits[2] >> j) & 0xfffff) 128 | ((65 - i) << 20); 129 u->L[_1] = (bits[2] << i | bits[1] >> j) & 0xffffffffL; 130 u->L[2+_0] = bits[1] & ((1L << j) - 1); 131 u->L[2+_1] = bits[0]; 132 break; 133 134 partly_normal: 135 i = hi0bits(bits[2]) - 11; 136 if (i < 0) { 137 j = -i; 138 i += 32; 139 u->L[_0] = (bits[2] >> j & 0xfffff) | (33 + j) << 20; 140 u->L[_1] = ((bits[2] << i) | (bits[1] >> j)) & 0xffffffffL; 141 u->L[2+_0] = bits[1] & ((1L << j) - 1); 142 u->L[2+_1] = bits[0]; 143 break; 144 } 145 if (i == 0) { 146 u->L[_0] = (bits[2] & 0xfffff) | (33 << 20); 147 u->L[_1] = bits[1]; 148 u->L[2+_0] = 0; 149 u->L[2+_1] = bits[0]; 150 break; 151 } 152 j = 32 - i; 153 u->L[_0] = (((bits[2] << i) | (bits[1] >> j)) & 0xfffff) 154 | ((j + 1) << 20); 155 u->L[_1] = (bits[1] << i | bits[0] >> j) & 0xffffffffL; 156 u->L[2+_0] = 0; 157 u->L[2+_1] = bits[0] & ((1L << j) - 1); 158 break; 159 160 hardly_normal: 161 j = 11 - hi0bits(bits[1]); 162 i = 32 - j; 163 u->L[_0] = (bits[1] >> j & 0xfffff) | ((j + 1) << 20); 164 u->L[_1] = (bits[1] << i | bits[0] >> j) & 0xffffffffL; 165 u->L[2+_0] = 0; 166 u->L[2+_1] = bits[0] & ((1L << j) - 1); 167 break; 168 169 case STRTOG_Infinite: 170 u->L[_0] = u->L[2+_0] = 0x7ff00000; 171 u->L[_1] = u->L[2+_1] = 0; 172 break; 173 174 case STRTOG_NaN: 175 u->L[0] = u->L[2] = d_QNAN0; 176 u->L[1] = u->L[3] = d_QNAN1; 177 } 178 if (rv & STRTOG_Neg) { 179 u->L[ _0] |= 0x80000000L; 180 u->L[2+_0] |= 0x80000000L; 181 } 182 return rv; 183 } 184