1
2
3#include <stdint.h>
4#include <stdio.h>
5
6union u {
7 struct { uint64_t sig; uint16_t sign_exp; } s;
8 long double ld;
9};
10
11volatile union u ld_pseudo_m16382 = { .s = { UINT64_C(1) << 63, 0 } };
12
13volatile long double ld_res;
14
15int main(void)
16{
17 short cw;
18 int ret = 0;
19 ld_res = ld_pseudo_m16382.ld + ld_pseudo_m16382.ld;
20 if (ld_res != 0x1p-16381L) {
21 printf("FAIL: pseudo-denormal add\n");
22 ret = 1;
23 }
24 if (ld_pseudo_m16382.ld != 0x1p-16382L) {
25 printf("FAIL: pseudo-denormal compare\n");
26 ret = 1;
27 }
28
29 __asm__ volatile ("fnstcw %0" : "=m" (cw));
30 cw = (cw & ~0xc00) | 0x800;
31 __asm__ volatile ("fldcw %0" : : "m" (cw));
32 __asm__ ("frndint" : "=t" (ld_res) : "0" (ld_pseudo_m16382.ld));
33 if (ld_res != 1.0L) {
34 printf("FAIL: pseudo-denormal round-to-integer\n");
35 ret = 1;
36 }
37 return ret;
38}
39
