/* { dg-do run } */ /* { dg-require-effective-target stdint_types } */ /* { dg-options "-O2" } */ #include extern void abort (void); uint64_t __attribute__((noinline)) byteswap64(uint64_t x) { uint32_t a = x >> 32; uint32_t b = (uint32_t) x; return ((uint64_t) ((((((b)) >> (8)) | (((b)) << (32 - (8)))) & 0xff00ff00L) | (((((b)) << (8)) | (((b)) >> (32 - (8)))) & 0x00ff00ffL)) << 32) | (uint64_t) ((((((a)) >> (8)) | (((a)) << (32 - (8)))) & 0xff00ff00L) | (((((a)) << (8)) | (((a)) >> (32 - (8)))) & 0x00ff00ffL)); } int main () { uint64_t in = (uint64_t)0x01020304 << 32 | 0x05060708; uint64_t cmp = (uint64_t)0x08070605 << 32 | 0x04030201; if (cmp != byteswap64 (in)) abort (); return 0; }