The following improves code-generation for PR63844 by using a restrict qualified reference type for the OMP receiver decl. This improves alias analysis and points-to analysis enough to usually allow invariant and store motion where that was possible in the non-split-out variant.
Bootstrapped and tested on x86_64-unknown-linux-gnu, ok for trunk? Sadly I don't have a good testcase (for example one that wasn't vectorized before but is now). We can add one later - ISTR there were a few other bugs about not vectorizing with -fopenmp, I'll try to find them again and see whether they are fixed. Thanks, Richard. 2014-11-19 Richard Biener <rguent...@suse.de> PR tree-optimization/63844 * omp-low.c (fixup_child_record_type): Use a restrict qualified referece type for the receiver parameter. Index: gcc/omp-low.c =================================================================== --- gcc/omp-low.c (revision 217692) +++ gcc/omp-low.c (working copy) @@ -1517,7 +1517,8 @@ fixup_child_record_type (omp_context *ct layout_type (type); } - TREE_TYPE (ctx->receiver_decl) = build_pointer_type (type); + TREE_TYPE (ctx->receiver_decl) + = build_qualified_type (build_reference_type (type), TYPE_QUAL_RESTRICT); } /* Instantiate decls as necessary in CTX to satisfy the data sharing