| /* Test double on x86. */ |
| |
| /* { dg-do run } */ |
| /* { dg-options -O2 } */ |
| |
| extern void abort (void); |
| |
| static __inline double |
| mypow (double __x, double __y) |
| { |
| register double __value, __exponent; |
| long __p = (long) __y; |
| if (__y == (double) __p) |
| { |
| double __r = 1.0; |
| if (__p == 0) |
| return 1.0; |
| if (__p < 0) |
| { |
| __p = -__p; |
| __x = 1.0 / __x; |
| } |
| while (1) |
| { |
| if (__p & 1) |
| __r *= __x; |
| __p >>= 1; |
| if (__p == 0) |
| return __r; |
| __x *= __x; |
| } |
| } |
| __asm __volatile__ |
| ("fmul %%st(1),%%st\n\t" /* y * log2(x) */ |
| "fst %%st(1)\n\t" |
| "frndint\n\t" /* int(y * log2(x)) */ |
| "fxch %%st(1)\n\t" |
| "fsub %%st(1),%%st\n\t" /* fract(y * log2(x)) */ |
| "f2xm1\n\t" /* 2^(fract(y * log2(x))) - 1 */ |
| : "=t" (__value), "=u" (__exponent) : "0" (__x), "1" (__y)); |
| __value += 1.0; |
| __asm __volatile__ |
| ("fscale" |
| : "=t" (__value) : "0" (__value), "u" (__exponent)); |
| return __value; |
| } |
| |
| const double E1 = 2.71828182845904523536028747135; |
| |
| double fact (double x) |
| { |
| double corr; |
| corr = 1.0; |
| return corr * mypow(x/E1, x); |
| } |
| |
| int main () |
| { |
| double y, z; |
| |
| y = fact (46.2); |
| z = mypow (46.2/E1, 46.2); |
| |
| #if 0 |
| printf ("%26.19e, %26.19e\n", y, z); |
| #endif |
| |
| if (y > z) |
| y -= z; |
| else |
| y = z - y; |
| |
| y /= z; |
| if (y > 0.1) |
| abort (); |
| |
| return 0; |
| } |
