HI All, Here is updated patch which implements Richard proposal to use vector comparison with boolean result instead of target hook. Support for it was added to ix86_expand_branch.
Any comments will be appreciated. Bootstrap and regression testing did not show any new failures. ChangeLog: 2015-08-06 Yuri Rumyantsev <ysrum...@gmail.com> * config/i386/i386.c (ix86_expand_branch): Implement vector comparison with boolean result. * config/i386/sse.md (define_expand "cbranch<mode>4): Add define for vector comparion. * fold-const.c (fold_relational_const): Add handling of vector comparison with boolean result. * params.def (PARAM_ZERO_TEST_FOR_STORE_MASK): New DEFPARAM. * params.h (ENABLE_ZERO_TEST_FOR_STORE_MASK): new macros. * tree-cfg.c (verify_gimple_comparison): Add test for vector comparion with boolean result. * tree-ssa-forwprop.c (forward_propagate_into_comparison_1): Do not propagate vector comparion with boolean result. * tree-vect-stmts.c (vectorizable_mask_load_store): Initialize has_mask_store field of vect_info. * tree-vectorizer.c: Include files ssa.h, cfghooks.h and params.h. (is_valid_sink): New function. (optimize_mask_stores): New function. (vectorize_loops): Invoke optimaze_mask_stores for loops having masked stores. * tree-vectorizer.h (loop_vec_info): Add new has_mask_store field and correspondent macros. gcc/testsuite/ChangeLog: * gcc.target/i386/avx2-vect-mask-store-move1.c: New test. 2015-07-27 11:48 GMT+03:00 Richard Biener <richard.guent...@gmail.com>: > On Fri, Jul 24, 2015 at 9:11 PM, Jeff Law <l...@redhat.com> wrote: >> On 07/24/2015 03:16 AM, Richard Biener wrote: >>>> >>>> Is there any rationale given anywhere for the transformation into >>>> conditional expressions? ie, is there any reason why we can't have a >>>> GIMPLE_COND where the expression is a vector condition? >>> >>> >>> No rationale for equality compare which would have the semantic of >>> having all elements equal or not equal. But you can't define a sensible >>> ordering (that HW implements) for other compare operators and you >>> obviously need a single boolean result, not a vector of element comparison >>> results. >> >> Right. EQ/NE only as others just don't have any real meaning. >> >> >>> I've already replied that I'm fine allowing ==/!= whole-vector compares. >>> But one needs to check whether expansion does anything sensible >>> with them (either expand to integer subreg compares or add optabs >>> for the compares). >> >> Agreed, EQ/NE for whole vector compares only would be fine for me too under >> the same conditions. > > Btw, you can already do this on GIMPLE by doing > > TImode vec_as_int = VIEW_CONVERT_EXPR <TImode> (vec_2); > if (vec_as_int == 0) > ... > > which is what the RTL will look like in the end. So not sure if making this > higher-level in GIMPLE is good or required. > > Richard. > >> jeff
patch.4
Description: Binary data
