| /* { 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" } } */ |
