cachepc-qemu

Fork of AMDESE/qemu with changes for cachepc side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-qemu
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test-i386-pseudo-denormal.c (948B)

      1/* Test pseudo-denormal operations.  */
      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    /* Set round-upward.  */
     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}