/* { dg-do compile } */
/* { dg-options "-O2 -fdump-tree-optimized -fdump-tree-reassoc-details" } */
extern int a0, a1, a2, a3, a4;
int f ()
{
int b0, b1, b2, b3, b4;
/* this can be optimized to four additions... */
b4 = a4 + a3 + a2 + a1 + a0;
b3 = a3 + a2 + a1 + a0;
b2 = a2 + a1 + a0;
b1 = a1 + a0;
/* This is actually 0 */
return b4 - b3 + b2 - b1 - a4 - a2;
}
/* { dg-final { scan-tree-dump-times "Reassociating by rank" 3 "reassoc" } } */
/* { dg-final { scan-tree-dump-times "return 0" 1 "optimized" { xfail *-*-* } } } */
/* { dg-final { cleanup-tree-dump "optimized" } } */
/* { dg-final { cleanup-tree-dump "reassoc" } } */
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