1 /*
2 (C) Copyright IBM Corp. 2009
3 
4 All rights reserved.
5 
6 Redistribution and use in source and binary forms, with or without
7 modification, are permitted provided that the following conditions are met:
8 
9 * Redistributions of source code must retain the above copyright notice,
10 this list of conditions and the following disclaimer.
11 * Redistributions in binary form must reproduce the above copyright
12 notice, this list of conditions and the following disclaimer in the
13 documentation and/or other materials provided with the distribution.
14 * Neither the name of IBM nor the names of its contributors may be
15 used to endorse or promote products derived from this software without
16 specific prior written permission.
17 
18 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
19 AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
22 LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23 CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24 SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25 INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26 CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28 POSSIBILITY OF SUCH DAMAGE.
29 */
30 
31 #include <stdlib.h>
32 #include "local.h"
33 #include "mprec.h"
34 #undef FLT_ROUNDS
35 
36 #ifdef _HAVE_LONG_DOUBLE
37 
38 #if defined (__x86_64__) || defined (__i386__)
39 static const int map[] = {
40         1,      /* round to nearest */
41         3,      /* round to zero */
42         2,      /* round to negative infinity */
43         0       /* round to positive infinity */
44 };
45 
46 int
__flt_rounds(void)47 __flt_rounds(void)
48 {
49         int x;
50 
51         /* Assume that the x87 and the SSE unit agree on the rounding mode. */
52         __asm("fnstcw %0" : "=m" (x));
53         return (map[(x >> 10) & 0x03]);
54 }
55 #define FLT_ROUNDS __flt_rounds()
56 #else
57 #define FLT_ROUNDS 0
58 #endif
59 
60 long double
_strtold_r(struct _reent * ptr,const char * __restrict s00,char ** __restrict se)61 _strtold_r (struct _reent *ptr, const char *__restrict s00,
62 	    char **__restrict se)
63 {
64 #ifdef _LDBL_EQ_DBL
65   /* On platforms where long double is as wide as double.  */
66   return _strtod_r (ptr, s00, se);
67 #else
68   long double result;
69 
70   _strtorx_r (ptr, s00, se, FLT_ROUNDS, &result);
71   return result;
72 #endif
73 }
74 
75 long double
strtold(const char * __restrict s00,char ** __restrict se)76 strtold (const char *__restrict s00, char **__restrict se)
77 {
78   return _strtold_r (_REENT, s00, se);
79 }
80 
81 #endif /* _HAVE_LONG_DOUBLE */
82 
83