1 /* Test double on x86. */
2
3 /* { dg-do run } */
4 /* { dg-options -O2 } */
5
6 extern void abort (void);
7
8 static __inline double
mypow(double __x,double __y)9 mypow (double __x, double __y)
10 {
11 register double __value, __exponent;
12 long __p = (long) __y;
13 if (__y == (double) __p)
14 {
15 double __r = 1.0;
16 if (__p == 0)
17 return 1.0;
18 if (__p < 0)
19 {
20 __p = -__p;
21 __x = 1.0 / __x;
22 }
23 while (1)
24 {
25 if (__p & 1)
26 __r *= __x;
27 __p >>= 1;
28 if (__p == 0)
29 return __r;
30 __x *= __x;
31 }
32 }
33 __asm __volatile__
34 ("fmul %%st(1),%%st\n\t" /* y * log2(x) */
35 "fst %%st(1)\n\t"
36 "frndint\n\t" /* int(y * log2(x)) */
37 "fxch %%st(1)\n\t"
38 "fsub %%st(1),%%st\n\t" /* fract(y * log2(x)) */
39 "f2xm1\n\t" /* 2^(fract(y * log2(x))) - 1 */
40 : "=t" (__value), "=u" (__exponent) : "0" (__x), "1" (__y));
41 __value += 1.0;
42 __asm __volatile__
43 ("fscale"
44 : "=t" (__value) : "0" (__value), "u" (__exponent));
45 return __value;
46 }
47
48 const double E1 = 2.71828182845904523536028747135;
49
fact(double x)50 double fact (double x)
51 {
52 double corr;
53 corr = 1.0;
54 return corr * mypow(x/E1, x);
55 }
56
main()57 int main ()
58 {
59 double y, z;
60
61 y = fact (46.2);
62 z = mypow (46.2/E1, 46.2);
63
64 #if 0
65 printf ("%26.19e, %26.19e\n", y, z);
66 #endif
67
68 if (y > z)
69 y -= z;
70 else
71 y = z - y;
72
73 y /= z;
74 if (y > 0.1)
75 abort ();
76
77 return 0;
78 }
79