https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92645
--- Comment #15 from Richard Biener <rguenth at gcc dot gnu.org> --- Author: rguenth Date: Thu Nov 28 12:22:04 2019 New Revision: 278806 URL: https://gcc.gnu.org/viewcvs?rev=278806&root=gcc&view=rev Log: 2019-11-28 Richard Biener <rguent...@suse.de> PR tree-optimization/92645 * tree-ssa-forwprop.c (get_bit_field_ref_def): Also handle conversions inside a mode class. Remove restriction on preserving the element size. (simplify_vector_constructor): Deal with the above and for identity permutes also try using VEC_UNPACK_[FLOAT_]LO_EXPR and VEC_PACK_TRUNC_EXPR. * gcc.target/i386/pr92645-4.c: New testcase. Added: trunk/gcc/testsuite/gcc.target/i386/pr92645-4.c Modified: trunk/gcc/ChangeLog trunk/gcc/testsuite/ChangeLog trunk/gcc/tree-ssa-forwprop.c