https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92657
--- Comment #3 from Adhemerval Zanella <adhemerval.zanella at linaro dot org> --- (In reply to Adhemerval Zanella from comment #2) > (In reply to Andrew Pinski from comment #1) > > Again, this is not due to tree-ch at all. This is due to the code motion > > passes move invariant load/stores out of the loop. Tree-ch pass just allows > > those passes to work. > > > > All three (gcse, tree pre and tree lim) need to be disabled to see the > > difference as all three are able to do the transformation. > > Sorry if I was not clear that tree-ch is not the culprit, but rather that it > enabled further optimizations to increase register pressure. But as I added > by disabling gcse, tree pre, and tree lim does help total stack usage, but > it does not reach on same level as disabling tree-ch. Ok, gcse, tree pre and tree lim are just tree of the flags that are increasing the stack. Other not enabled by Os but enabled by O2 are increasing stack usage. Maybe changing the title to "High stack usage with tree-loop-im, tree-pre, and gcse"?
