1 /* s_copysignl.c -- long double version of s_copysign.c.
2 * Conversion to long double by Ulrich Drepper,
3 * Cygnus Support, drepper@cygnus.com.
4 */
5
6 /*
7 * ====================================================
8 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
9 *
10 * Developed at SunPro, a Sun Microsystems, Inc. business.
11 * Permission to use, copy, modify, and distribute this
12 * software is freely granted, provided that this notice
13 * is preserved.
14 * ====================================================
15 */
16
17 /*
18 * copysignl(long double x, long double y)
19 * copysignl(x,y) returns a value with the magnitude of x and
20 * with the sign bit of y.
21 */
22
23 #include <endian.h>
24 #include <stdint.h>
25
26 #if __FLOAT_WORD_ORDER == BIG_ENDIAN
27
28 typedef union
29 {
30 long double value;
31 struct
32 {
33 int sign_exponent:16;
34 unsigned int empty:16;
35 uint32_t msw;
36 uint32_t lsw;
37 } parts;
38 } ieee_long_double_shape_type;
39
40 #endif
41
42 #if __FLOAT_WORD_ORDER == LITTLE_ENDIAN
43
44 typedef union
45 {
46 long double value;
47 struct
48 {
49 uint32_t lsw;
50 uint32_t msw;
51 int sign_exponent:16;
52 unsigned int empty:16;
53 } parts;
54 } ieee_long_double_shape_type;
55
56 #endif
57
58 /* Get int from the exponent of a long double. */
59
60 #define GET_LDOUBLE_EXP(exp,d) \
61 do { \
62 ieee_long_double_shape_type ge_u; \
63 ge_u.value = (d); \
64 (exp) = ge_u.parts.sign_exponent; \
65 } while (0)
66
67 /* Set exponent of a long double from an int. */
68
69 #define SET_LDOUBLE_EXP(d,exp) \
70 do { \
71 ieee_long_double_shape_type se_u; \
72 se_u.value = (d); \
73 se_u.parts.sign_exponent = (exp); \
74 (d) = se_u.value; \
75 } while (0)
76
77 long double copysignl(long double x, long double y);
78 libc_hidden_proto(copysignl);
79
copysignl(long double x,long double y)80 long double copysignl(long double x, long double y)
81 {
82 uint32_t es1,es2;
83 GET_LDOUBLE_EXP(es1,x);
84 GET_LDOUBLE_EXP(es2,y);
85 SET_LDOUBLE_EXP(x,(es1&0x7fff)|(es2&0x8000));
86 return x;
87 }
88
89 libc_hidden_def(copysignl);
90