modernc.org/ccgo/v3@v3.16.14/lib/testdata/gcc-9.1.0/gcc/testsuite/gcc.c-torture/execute/pr27285.c (about)

     1  /* PR tree-optimization/27285 */
     2  
     3  extern void abort (void);
     4  
     5  struct S { unsigned char a, b, c, d[16]; };
     6  
     7  void __attribute__ ((noinline))
     8  foo (struct S *x, struct S *y)
     9  {
    10    int a, b;
    11    unsigned char c, *d, *e;
    12  
    13    b = x->b;
    14    d = x->d;
    15    e = y->d;
    16    a = 0;
    17    while (b)
    18      {
    19        if (b >= 8)
    20  	{
    21  	  c = 0xff;
    22  	  b -= 8;
    23  	}
    24        else
    25  	{
    26  	  c = 0xff << (8 - b);
    27  	  b = 0;
    28  	}
    29  
    30        e[a] = d[a] & c;
    31        a++;
    32      }
    33  }
    34  
    35  int
    36  main (void)
    37  {
    38    struct S x = { 0, 25, 0, { 0xaa, 0xbb, 0xcc, 0xdd }};
    39    struct S y = { 0, 0, 0, { 0 }};
    40  
    41    foo (&x, &y);
    42    if (x.d[0] != y.d[0] || x.d[1] != y.d[1]
    43        || x.d[2] != y.d[2] || (x.d[3] & 0x80) != y.d[3])
    44      abort ();
    45     return 0;
    46  }