gcc/testsuite/gcc.dg/max-1.c

   1 /* PR middle-end/18548 */
   2 /* Test case reduced by Andrew Pinski <pinskia@physics.uc.edu> */
   3 /* { dg-do run } */
   4 /* { dg-options "-O1 " } */
   5 /* Option -fno-tree-lrs removed By Andrew MacLeod since it is no longer
   6    supported in the compiler beginning with GCC 4.3.  */
   7 /* m32c has varying sized pointers */
   8 /* { dg-skip-if "" { "m32c-*-*" } { "*" } { "-mcpu=m32c" "-mcpu=m32cm" } } */
   9
  10 __extension__ typedef __INTPTR_TYPE__ intptr_t;
  11
  12 extern void abort (void);
  13
  14 intptr_t fff[10];
  15
  16 void f(intptr_t a, intptr_t b)
  17 {
  18   intptr_t crcc = b;
  19   intptr_t d = *((intptr_t*)(a+1));
  20   int i;
  21
  22   a = d >= b? d:b;
  23
  24
  25   for(i=0;i<10;i++)
  26    fff[i] = a;
  27 }
  28
  29 /* The variable a cannot be a local variable as we get better aliasing
  30    now and decide that the store to a is dead.  The better aliasing comes
  31    from better representation of pointer arithmetic. */
  32 intptr_t a = 10;
  33 int main(void)
  34 {
  35   int i;
  36   f((intptr_t)(&a)-1,0);
  37   for(i = 0;i<10;i++)
  38    if (fff[i]!=10)
  39     abort ();
  40   return 0;
  41 }
  42