https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109610
--- Comment #13 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by hongtao Liu <liuho...@gcc.gnu.org>: https://gcc.gnu.org/g:4fb66b2329319e9b47e89200d613b6f741a114fc commit r14-1252-g4fb66b2329319e9b47e89200d613b6f741a114fc Author: liuhongt <hongtao....@intel.com> Date: Tue May 16 10:36:16 2023 +0800 Only use NO_REGS in cost calculation when !hard_regno_mode_ok for GENERAL_REGS and mode. r14-172-g0368d169492017 replaces GENERAL_REGS with NO_REGS in cost calculation when the preferred register class are not known yet. It regressed powerpc PR109610 and PR109858, it looks too aggressive to use NO_REGS when mode can be allocated with GENERAL_REGS. The patch takes a step back, still use GENERAL_REGS when hard_regno_mode_ok for mode and GENERAL_REGS, otherwise uses NO_REGS. gcc/ChangeLog: PR target/109610 PR target/109858 * ira-costs.cc (scan_one_insn): Only use NO_REGS in cost calculation when !hard_regno_mode_ok for GENERAL_REGS and mode, otherwise still use GENERAL_REGS.
