On Mon, Apr 10, 2017 at 4:35 PM, Bin Cheng <bin.ch...@arm.com> wrote: > Hi, > This is another try fixing PR80153. It's based on richi's idea which is > easier to understand than my > previous patch. The patch gets base pointer from the first element of > pointer aff_tree, builds result > expression in aff_tree's type unconditionally. With this patch, A) we can do > unconditional type > conversion on element in add_elt_to_tree, which simplify the function a lot; > B) Except for below > mentioned fallout, customer of aff_tree doesn't need to do explicit > conversion for result expression > of aff_combination_to_tree now. > > Though this patch can handle normal constant base pointer_plus_expr, e.g, > ((char *)1024 + (size_t)x), > we still can't handle extreme case in which x is of pointer type and its coef > is 1. I believe this is > a latent problem in tree-affine.c all the time. It's not exposed because the > biggest customer (ivopt) > always generates code in unsigned, rather than pointer type. Let's see if > this patch will uncover the issue. > > I also need to do more invariant check in rewrite_use_nonlinear_expr for test > gcc.dg/tree-ssa/reassoc-19.c. > It relies on wrong behavior of tree-affine.c addressed in this patch. > > Bootstrap and test on X86_64 and AArch64. Is it OK if no failures? The next > patch addresses a > breakage of tree-affine.c usage.
Ok. Thanks, Richard. > Thanks, > bin > > 2017-04-07 Richard Biener <rguent...@suse.de> > Bin Cheng <bin.ch...@arm.com> > > PR tree-optimization/80153 > * tree-affine.c (aff_combination_to_tree): Get base pointer from > the first element of pointer type aff_tree. Build result expr in > aff_tree's type. > (add_elt_to_tree): Convert to type unconditionally. Remove other > fold_convert calls. > * tree-ssa-loop-ivopts.c (alloc_iv): Pass in consistent types. > (rewrite_use_nonlinear_expr): Check invariant using iv information. > > gcc/testsuite/ChangeLog > 2017-04-07 Bin Cheng <bin.ch...@arm.com> > > PR tree-optimization/80153 > * gcc.c-torture/execute/pr80153.c: New.
