memcheck/tests/amd64/bug279698.c

   1 /* A very trivial test for undefinedness propagation through
   2    saturating narrowing.  Obviously need a much more thorough test.
   3 */
   4 #include <stdio.h>
   5 #include <assert.h>
   6 #include "../../memcheck.h"
   7 int main()
   8 {
   9     unsigned char data[32], vbits[32];
  10     __asm__ __volatile__
  11        ("movdqu     (%0), %%xmm0 \n"
  12         "packuswb %%xmm0, %%xmm0 \n"
  13         "movdqu   %%xmm0, 16(%0) \n"
  14         ::"r"(data)
  15         :"memory","xmm0"
  16     );
  17     unsigned int res =
  18        VALGRIND_GET_VBITS( data, vbits, 32 );
  19     assert(res == 1); /* 1 == success */
  20     int i, j;
  21     for(i=0; i<2; i++) {
  22         for(j=0; j<16; j++)
  23             printf("%02x ", vbits[i*16+j]);
  24         printf("\n");
  25     }
  26     return 0;
  27 }