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/* 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;
}
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