https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116444
--- Comment #1 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Andre Simoes Dias Vieira <avie...@gcc.gnu.org>: https://gcc.gnu.org/g:7766a2c1eb683eeee352ce117e8ed014665f392f commit r15-4066-g7766a2c1eb683eeee352ce117e8ed014665f392f Author: Andre Vieira <andre.simoesdiasvie...@arm.com> Date: Fri Oct 4 13:43:46 2024 +0100 arm: Fix missed CE optimization for armv8.1-m.main [PR 116444] This patch restores missed optimizations for armv8.1-m.main targets that were missed when the generation of csinc, csinv and csneg were enabled for the same with patch series containing: commit c2bb84be4a6e581bbf45891457ee632a07416982 Author: Sudi Das <sudi....@arm.com> Date: Fri Sep 18 15:47:46 2020 +0100 [PATCH 2/5][Arm] New pattern for CSINV instructions The original patch series makes use of the "noce" machinery to transform RTL into patterns that later match the Armv8.1-M Mainline, by getting the target hook TARGET_HAVE_CONDITIONAL_EXECUTION, to return FALSE for such targets prior to reload_completed. The same machinery however was transforming other RTL patterns which were later on causing the "ce" pass post reload_completed to no longer optimize conditional execution opportunities, which was causing the regression observed in PR target/116444, a regression of 'testsuite/gcc.target/arm/thumb-ifcvt-2.c' when ran for an Armv8.1-M Mainline target. This patch implements the target hook TARGET_NOCE_CONVERSION_PROFITABLE_P to only allow "noce" to generate patterns that match CSINV, CSINC and CSNEG. Thus ensuring that the early "ce" passes do not ruin things for later ones. gcc/ChangeLog: PR target/116444 * config/arm/arm-protos.h (arm_noce_conversion_profitable_p): New declaration. * config/arm/arm.cc (arm_is_v81m_cond_insn): New helper function used in ... (arm_noce_conversion_profitable_p): ... here. New function to implement ... (TARGET_NOCE_PROFITABLE_P): ... this target hook. New define.
