| /* { dg-do compile } */ |
| /* { dg-options "-O2 -ftree-parallelize-loops=4 -fdump-tree-parloops2-details -fdump-tree-optimized" } */ |
| |
| #include <stdlib.h> |
| #include <stdio.h> |
| |
| int main() |
| { |
| unsigned int x, y, idx, H = 1024, W = 1024; |
| |
| int * tmps = (int *)malloc(H*W*sizeof(int)); |
| |
| /* This loop gets parallelized even though output dependences exist |
| between writes to 'tmps' that prevent parallelization. |
| For example: tmps[1] = 1, ..., tmps[1] = 17. */ |
| |
| for(x = 1; x < H; x++) |
| { |
| for(y = 1; y < W; y++) |
| { |
| idx = x*W+y; |
| tmps[idx % 4096] = idx; |
| } |
| } |
| |
| for(x = 1; x < 8; x++) |
| printf("tmps[%d]=%d\n", x, tmps[x]); |
| |
| return 0; |
| } |
| /* Check that no loop gets parallelized. */ |
| |
| /* { dg-final { scan-tree-dump-times "SUCCESS: may be parallelized" 0 "parloops2" } } */ |
| /* { dg-final { scan-tree-dump-times "loopfn" 0 "optimized" } } */ |
