On 04/18/2017 04:54 AM, Bin Cheng wrote: > Hi, > This is the same patch posted at > https://gcc.gnu.org/ml/gcc-patches/2016-05/msg02000.html, > after rebase against this patch series. This patch was blocked because > without this patch > series, it could generate worse code on targets with limited addressing mode > support, like > AArch64. > There was some discussion about alternative fix for PRs, but after thinking > twice I think > this fix is in the correct direction. A CSE interface is useful to clean up > code generated > in vectorizer, and we should improve this CSE interface into a region base > one. for the > moment, optimal code is not generated on targets like x86, I believe it's > because the CSE > is weak and doesn't cover all basic blocks generated by vectorizer, the issue > should be > fixed if region-based CSE is implemented. > Is it OK? > > Thanks, > bin > 2017-04-11 Bin Cheng <bin.ch...@arm.com> > > PR tree-optimization/68030 > PR tree-optimization/69710 > * tree-ssa-dom.c (cse_bbs): New function. > * tree-ssa-dom.h (cse_bbs): New declaration. > * tree-vect-data-refs.c (vect_create_addr_base_for_vector_ref): > Re-associate address by splitting constant offset. > (vect_create_data_ref_ptr, vect_setup_realignment): Record changed > basic block. > * tree-vect-loop-manip.c (vect_gen_prolog_loop_niters): Record > changed basic block. > * tree-vectorizer.c (tree-ssa-dom.h): Include header file. > (changed_bbs): New variable. > (vectorize_loops): Allocate and free CHANGED_BBS. Call cse_bbs. > * tree-vectorizer.h (changed_bbs): New declaration. > So are you still interested in moving this forward Bin? I know you did a minor update in response to Michael Meissner's problems. Is there another update planned?
THe only obvious thing I'd suggest changing in the DOM interface is to have continue to walk the dominator tree, but do nothing for blocks that are not in changed_bbs. That way you walk blocks in changed_bbs in dominator order rather than in bb->index order. Jeff
