gcc/testsuite/gcc.dg/pr20126.c

   1 /* dg-do run */
   2 /* dg-options "-O2" */
   3
   4 /* PR target/20126 was not really target-specific, but rather a loop's
   5    failure to take into account the possibility that a DEST_ADDR giv
   6    replacement might fail, such as when you attempt to replace a REG
   7    with a PLUS in one of the register_operands of cmpstrqi_rex_1.  */
   8
   9 extern void abort (void);
  10
  11 typedef struct { int a; char b[3]; } S;
  12 S c = { 2, "aa" }, d = { 2, "aa" };
  13
  14 void *
  15 bar (const void *x, int y, int z)
  16 {
  17   return (void *) 0;
  18 }
  19
  20 int
  21 foo (S *x, S *y)
  22 {
  23   const char *e, *f, *g;
  24   int h;
  25
  26   h = y->a;
  27   f = y->b;
  28   e = x->b;
  29
  30   if (h == 1)
  31     return bar (e, *f, x->a) != 0;
  32
  33   g = e + x->a - h;
  34   while (e <= g)
  35     {
  36       const char *t = e + 1;
  37       if (__builtin_memcmp (e, f, h) == 0)
  38         return 1;
  39       e = t;
  40     }
  41   return 0;
  42 }
  43
  44 int
  45 main (void)
  46 {
  47   if (foo (&c, &d) != 1)
  48     abort ();
  49   return 0;
  50 }