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/* SPDX-License-Identifier: GPL-2.0-or-later */
#include <stdio.h>
#include <math.h>
#include <fenv.h>
union U {
double d;
unsigned long long l;
};
union U x = { .l = 0x4ff0000000000000ULL };
union U y = { .l = 0x2ff0000000000000ULL };
union U r;
int main()
{
#ifdef FE_DOWNWARD
fesetround(FE_DOWNWARD);
#if defined(__loongarch__)
asm("fnmsub.d %0, %1, %1, %2" : "=f"(r.d) : "f"(x.d), "f"(y.d));
#elif defined(__powerpc64__)
asm("fnmsub %0,%1,%1,%2" : "=f"(r.d) : "f"(x.d), "f"(y.d));
#elif defined(__s390x__) && 0 /* need -march=z14 */
asm("vfnms %0,%1,%1,%2,0,3" : "=f"(r.d) : "f"(x.d), "f"(y.d));
#else
r.d = -fma(x.d, x.d, -y.d);
#endif
if (r.l != 0xdfefffffffffffffULL) {
printf("r = %.18a (%016llx)\n", r.d, r.l);
return 1;
}
#endif
return 0;
}
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