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/* { dg-options "-O3 -fdump-tree-lversion-details" } */
/* The read from y in f1 will be hoisted to the outer loop. In general
it's not worth versioning outer loops when the inner loops don't also
benefit.
This test is meant to be a slight counterexample, since versioning
does lead to cheaper outer-loop vectorization. However, the benefit
isn't enough to justify the cost. */
void
f1 (double *restrict x, double *restrict y, int step, int n)
{
for (int i = 0; i < n; ++i)
for (int j = 0; j < n; ++j)
x[i + j] = y[i * step];
}
/* A similar example in which the read can't be hoisted, but could
for example be handled by vectorizer alias checks. */
void
f2 (double *x, double *y, int step, int n)
{
for (int i = 0; i < n; ++i)
for (int j = 0; j < n; ++j)
x[i + j] = y[i * step];
}
/* { dg-final { scan-tree-dump-not {want to version} "lversion" } } */
/* { dg-final { scan-tree-dump-not {versioned} "lversion" } } */
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