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/* { dg-do compile } */
/* { dg-do run } */
/* { dg-options "-O2 -funroll-loops --param max-unroll-times=8 -fpredictive-commoning -fdump-tree-pcom-details -fno-tree-pre" } */
void abort (void);
unsigned fib[1000];
__attribute__ ((noinline))
void count_fib(void)
{
int i;
fib[0] = 0;
fib[1] = 1;
for (i = 2; i < 1000; i++)
fib[i] = (fib[i-1] + fib[i - 2]) & 0xffff;
}
unsigned avg[1000];
__attribute__ ((noinline))
void count_averages(int n)
{
int i;
for (i = 1; i < n; i++)
avg[i] = (((unsigned long) fib[i - 1] + fib[i] + fib[i + 1]) / 3) & 0xffff;
}
int main(void)
{
count_fib ();
count_averages (999);
if (fib[19] != 4181 || avg[19] != 4510)
abort ();
if (fib[999] != 162 || avg[998] != 21953)
abort ();
return 0;
}
/* Verify that both loops were transformed and unrolled. */
/* { dg-final { scan-tree-dump-times "Unrolling 2 times." 2 "pcom"} } */
/* Also check that we undid the transformation previously made by PRE.
??? PRE now does the predictive commoning in count_averages. */
/* dg-final { scan-tree-dump-times "looparound ref" 1 "pcom" } */
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