modernc.org/ccgo/v3@v3.16.14/lib/testdata/gcc-9.1.0/gcc/testsuite/gcc.c-torture/execute/pr65215-3.c (about)

     1  /* PR tree-optimization/65215 */
     2  
     3  struct S { unsigned long long l1 : 24, l2 : 8, l3 : 32; };
     4  
     5  static inline unsigned int
     6  foo (unsigned int x)
     7  {
     8    return (x >> 24) | ((x >> 8) & 0xff00) | ((x << 8) & 0xff0000) | (x << 24);
     9  }
    10  
    11  __attribute__((noinline, noclone)) unsigned long long
    12  bar (struct S *x)
    13  {
    14    unsigned long long x1 = foo (((unsigned int) x->l1 << 8) | x->l2);
    15    unsigned long long x2 = foo (x->l3);
    16    return (x2 << 32) | x1;
    17  }
    18  
    19  int
    20  main ()
    21  {
    22    if (__CHAR_BIT__ != 8 || sizeof (unsigned int) != 4 || sizeof (unsigned long long) != 8)
    23      return 0;
    24    struct S s = { 0xdeadbeU, 0xefU, 0xfeedbea8U };
    25    unsigned long long l = bar (&s);
    26    if (foo (l >> 32) != s.l3
    27        || (foo (l) >> 8) != s.l1
    28        || (foo (l) & 0xff) != s.l2)
    29      __builtin_abort ();
    30    return 0;
    31  }