gcc/testsuite/gcc.dg/tree-ssa/loop-3.c

   1 /* A test for strength reduction and induction variable elimination.
   2    Target is restricted to x86 type architectures, so that we may
   3    assume something about memory addressing modes.  */
   4
   5 /* { dg-do compile { target { { i?86-*-* x86_64-*-* } && nonpic } } } */
   6 /* { dg-options "-O1 -fdump-tree-optimized" } */
   7
   8 int arr_base[100];
   9
  10 int foo(int);
  11
  12 void xxx(void)
  13 {
  14   long iter;
  15
  16   for (iter = 0; iter < 100; iter++)
  17     arr_base[iter] = foo (iter);
  18 }
  19
  20 /* Access to arr_base[iter].y should not be strength reduced, since
  21    we have a memory mode including multiplication by 4.  */
  22
  23 /* { dg-final { scan-tree-dump-times "MEM\[^;\]* \* 4" 1 "optimized" } } */
  24
  25 /* And original induction variable should be preserved.  */
  26
  27 /* { dg-final { scan-tree-dump-times "int iter" 1 "optimized" } } */
  28