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/* { dg-do compile } */
/* { dg-options "-O1 -fscalar-evolutions -fdump-tree-scev-details" } */
int bar (void);
int foo ()
{
int a = -100;
/* This exercises a code with two loop nests. */
/* loop_1 runs 100 times. */
while (a < 0)
a++;
a -= 77;
/* loop_2 runs 26 times. */
while (a < 0)
a+=3;
}
/* The analyzer sees two loop nests:
for the first, it determines the evolution:
a -> {-100, +, 1}_1
and for the second, it determines that the first loop ends at 0 and then:
a -> {-77, +, 3}_2
When the constant propagation is postponed, the analyzer detects
for the second loop the evolution function:
a -> {a_5, +, 3}_2
*/
/* { dg-final { scan-tree-dump-times "nb_iterations 100" 1 "scev"} } */
/* { dg-final { scan-tree-dump-times "nb_iterations 26" 1 "scev"} } */
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