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#include <stdio.h>
#include <math.h>
typedef unsigned long long int ULong;
typedef
struct { double d; int i; } Res;
static void do_fprem ( Res* res, double x, double y )
{
ULong c3210;
double f64;
double xx = x;
double yy = y;
__asm__ __volatile__(
"finit\n\t"
"fldl %2\n\t"
"fldl %3\n\t"
"fprem\n\t"
"fstpl %1\n\t"
"movq %%rax,%%r15\n\t"
"xorq %%rax,%%rax\n\t"
"fnstsw %%ax\n\t"
"movq %%rax,%0\n\t"
"movq %%r15,%%rax"
: /*out*/ "=r" (c3210)
: /*in*/ "m" (f64), "m" (xx), "m" (yy)
: /*trash*/ "r15", "rax", "%st", "%st(1)", "cc"
);
res->d = f64;
res->i = (int)(c3210 & 0x4700); /* mask for C3,2,1,0 */
}
static void show ( char* s, Res* res )
{
printf("%s -> 0x%04x %f\n", s, (int)res->i, (double)res->d);
}
int main ( void )
{
Res r;
int i;
double theta;
do_fprem(&r, 10.1, 200.2); show("xx1", &r);
do_fprem(&r, 20.3, 1.44); show("xx2", &r);
for (i = 0; i < 20; i++) {
theta = (2.0 * 3.14159) / 10.0 * (double)i;
do_fprem(&r, 12.3*sin(theta), cos(theta)); show("xx", &r);
}
return 0;
}
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