gcc/testsuite/gcc.target/i386/crc32-2.c

/* { dg-do compile } */
/* { dg-options "-O2 -mcrc32" } */
/* { dg-final { scan-assembler "crc32q\[^\\n\]*rax" { target { ! { ia32 } } } } } */

unsigned long long
crc32d (unsigned long long x, unsigned long long y)
{
  return __builtin_ia32_crc32di (x, y);
}