http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50763
--- Comment #4 from vries at gcc dot gnu.org 2011-10-18 11:12:32 UTC --- Created attachment 25541 --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=25541 patch, handles case that either vuse1 or vuse2 is NULL_TREE in update_vuses. Currently testing on x86_64. 2011-10-18 Tom de Vries <t...@codesourcery.com> PR tree-optimization/50763 * tree-ssa-tail-merge.c (update_vuses): Add and use vuse1_phi_args argument. Set var to SSA_NAME_VAR of vuse1 or vuse2, and use var. Handle case that def_stmt2 is NULL. Use phi result as phi arg in case vuse1 or vuse2 is NULL_TREE. Replace uses of vuse1 if vuse2 is NULL_TREE. Remove code to limit replacement of uses. (replace_block_by): Update vops if phi_vuse1 or phi_vuse2 is NULL_TREE. Set vuse1_phi_args if vuse1 is a phi defined in bb1. Add vuse1_phi_args as argument to call to update_vuses. * gcc.dg/pr50763.c: New test.
