1 /****************************************************************
2
3 The author of this software is David M. Gay.
4
5 Copyright (C) 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
L_shift(ULong * x,ULong * x1,int i)34 static void L_shift (ULong *x, ULong *x1, int i)
35 {
36 int j;
37
38 i = 8 - i;
39 i <<= 2;
40 j = ULbits - i;
41 do {
42 *x |= x[1] << j;
43 x[1] >>= i;
44 } while(++x < x1);
45 }
46
hexnan(const char ** sp,FPI * fpi,ULong * x0)47 int hexnan (const char **sp, FPI *fpi, ULong *x0)
48 {
49 ULong c, h, *x, *x1, *xe;
50 const char *s;
51 int havedig, hd0, i, nbits;
52
53 if (!hexdig['0'])
54 hexdig_init_D2A();
55 nbits = fpi->nbits;
56 x = x0 + (nbits >> kshift);
57 if (nbits & kmask)
58 x++;
59 *--x = 0;
60 x1 = xe = x;
61 havedig = hd0 = i = 0;
62 s = *sp;
63 /* allow optional initial 0x or 0X */
64 while((c = *(const unsigned char*)(s+1)) && c <= ' ')
65 ++s;
66 if (s[1] == '0' && (s[2] == 'x' || s[2] == 'X')
67 && *(const unsigned char*)(s+3) > ' ')
68 s += 2;
69 while((c = *(const unsigned char*)++s)) {
70 if (!(h = hexdig[c])) {
71 if (c <= ' ') {
72 if (hd0 < havedig) {
73 if (x < x1 && i < 8)
74 L_shift(x, x1, i);
75 if (x <= x0) {
76 i = 8;
77 continue;
78 }
79 hd0 = havedig;
80 *--x = 0;
81 x1 = x;
82 i = 0;
83 }
84 while(*(const unsigned char*)(s+1) <= ' ')
85 ++s;
86 if (s[1] == '0' && (s[2] == 'x' || s[2] == 'X')
87 && *(const unsigned char*)(s+3) > ' ')
88 s += 2;
89 continue;
90 }
91 if (/*(*/ c == ')' && havedig) {
92 *sp = s + 1;
93 break;
94 }
95 #ifndef GDTOA_NON_PEDANTIC_NANCHECK
96 do {
97 if (/*(*/ c == ')') {
98 *sp = s + 1;
99 break;
100 }
101 } while((c = *++s));
102 #endif
103 return STRTOG_NaN;
104 }
105 havedig++;
106 if (++i > 8) {
107 if (x <= x0)
108 continue;
109 i = 1;
110 *--x = 0;
111 }
112 *x = (*x << 4) | (h & 0xf);
113 }
114 if (!havedig)
115 return STRTOG_NaN;
116 if (x < x1 && i < 8)
117 L_shift(x, x1, i);
118 if (x > x0) {
119 x1 = x0;
120 do *x1++ = *x++;
121 while(x <= xe);
122 do *x1++ = 0;
123 while(x1 <= xe);
124 }
125 else {
126 /* truncate high-order word if necessary */
127 if ( (i = nbits & (ULbits-1)) !=0)
128 *xe &= ((ULong)0xffffffff) >> (ULbits - i);
129 }
130 for(x1 = xe;; --x1) {
131 if (*x1 != 0)
132 break;
133 if (x1 == x0) {
134 *x1 = 1;
135 break;
136 }
137 }
138 return STRTOG_NaNbits;
139 }
140