https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113656
--- Comment #7 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Jakub Jelinek <ja...@gcc.gnu.org>: https://gcc.gnu.org/g:b59775b642bb2b1ecd2e6d52c988b9c432117bc8 commit r14-8652-gb59775b642bb2b1ecd2e6d52c988b9c432117bc8 Author: Jakub Jelinek <ja...@redhat.com> Date: Wed Jan 31 10:56:56 2024 +0100 simplify-rtx: Fix up last argument to simplify_gen_unary [PR113656] When simplifying e.g. (float_truncate:SF (float_truncate:DF (reg:XF)) or (float_truncate:SF (float_extend:XF (reg:DF)) etc. into (float_truncate:SF (reg:XF)) or (float_truncate:SF (reg:DF)) we call simplify_gen_unary with incorrect op_mode argument, it should be the argument's mode, but we call it with the outer mode instead. As these are all floating point operations, the argument always has non-VOIDmode and so we can just use that mode (as done in similar simplifications a few lines later), but neither FLOAT_TRUNCATE nor FLOAT_EXTEND are operations that should have the same modes of operand and result. This bug hasn't been a problem for years because normally op_mode is used only if the mode of op is VOIDmode, otherwise it is redundant, but r10-2139 added an assertion in some spots that op_mode is right even in such cases. 2024-01-31 Jakub Jelinek <ja...@redhat.com> PR rtl-optimization/113656 * simplify-rtx.cc (simplify_context::simplify_unary_operation_1) <case FLOAT_TRUNCATE>: Fix up last argument to simplify_gen_unary. * gcc.target/i386/pr113656.c: New test.
