https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121385
--- Comment #7 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Richard Henderson <r...@gcc.gnu.org>: https://gcc.gnu.org/g:976bad6ea48346b0dc31e68b035daa9569724fb5 commit r16-3146-g976bad6ea48346b0dc31e68b035daa9569724fb5 Author: Richard Henderson <richard.hender...@linaro.org> Date: Thu Aug 7 04:51:02 2025 +0000 aarch64: Remove cc clobber from *aarch64_tbz<LTGE><ALLI>1 There is a conflict between aarch64_tbzltdi1 and aarch64_cbltdi with respect to pnum_clobbers, resulting in a recog failure: 0xa1fffe fancy_abort(char const*, int, char const*) ../../gcc/diagnostics/context.cc:1640 0x81340e patch_jump_insn ../../gcc/cfgrtl.cc:1303 0xc0eafe redirect_branch_edge ../../gcc/cfgrtl.cc:1330 0xc0f372 cfg_layout_redirect_edge_and_branch ../../gcc/cfgrtl.cc:4736 0xbfb6b9 redirect_edge_and_branch(edge_def*, basic_block_def*) ../../gcc/cfghooks.cc:391 0x1fa9310 try_forward_edges ../../gcc/cfgcleanup.cc:561 0x1fa9310 try_optimize_cfg ../../gcc/cfgcleanup.cc:2931 0x1fa9310 cleanup_cfg(int) ../../gcc/cfgcleanup.cc:3143 0x1fe11e8 rest_of_handle_cse ../../gcc/cse.cc:7591 0x1fe11e8 execute ../../gcc/cse.cc:7622 The simplest solution is to remove the clobber from aarch64_tbz. This removes the possibility of expansion via TST+B.cond, which will merely fall back to TBNZ+B on shorter branches. gcc: PR target/121385 * config/aarch64/aarch64.md (*aarch64_tbz<LTGE><ALLI>1): Remove cc clobber and expansion via TST+Bcond. gcc/testsuite: PR target/121385 * gcc.target/aarch64/cmpbr-1.c: New.
