https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114603
--- Comment #1 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The trunk branch has been updated by Richard Sandiford <rsand...@gcc.gnu.org>: https://gcc.gnu.org/g:67cbb1c638d6ab3a9cb77e674541e2b291fb67df commit r14-9811-g67cbb1c638d6ab3a9cb77e674541e2b291fb67df Author: Richard Sandiford <richard.sandif...@arm.com> Date: Fri Apr 5 14:47:15 2024 +0100 aarch64: Fix bogus cnot optimisation [PR114603] aarch64-sve.md had a pattern that combined: cmpeq pb.T, pa/z, zc.T, #0 mov zd.T, pb/z, #1 into: cnot zd.T, pa/m, zc.T But this is only valid if pa.T is a ptrue. In other cases, the original would set inactive elements of zd.T to 0, whereas the combined form would copy elements from zc.T. gcc/ PR target/114603 * config/aarch64/aarch64-sve.md (@aarch64_pred_cnot<mode>): Replace with... (@aarch64_ptrue_cnot<mode>): ...this, requiring operand 1 to be a ptrue. (*cnot<mode>): Require operand 1 to be a ptrue. * config/aarch64/aarch64-sve-builtins-base.cc (svcnot_impl::expand): Use aarch64_ptrue_cnot<mode> for _x operations that are predicated with a ptrue. Represent other _x operations as fully-defined _m operations. gcc/testsuite/ PR target/114603 * gcc.target/aarch64/sve/acle/general/cnot_1.c: New test.
