https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115478
--- Comment #13 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Xi Ruoyao <xry...@gcc.gnu.org>: https://gcc.gnu.org/g:ea3ebe48150d2109845f2c4622ebff182f618d97 commit r15-7615-gea3ebe48150d2109845f2c4622ebff182f618d97 Author: Xi Ruoyao <xry...@xry111.site> Date: Mon Feb 10 23:39:24 2025 +0800 LoongArch: Accept ADD, IOR or XOR when combining objects with no bits in common [PR115478] Since r15-1120, multi-word shifts/rotates produces PLUS instead of IOR. It's generally a good thing (allowing to use our alsl instruction or similar instrunction on other architectures), but it's preventing us from using bytepick. For example, if we shift a __int128 by 16 bits, the higher word can be produced via a single bytepick.d instruction with immediate 2, but we got: srli.d $r12,$r4,48 slli.d $r5,$r5,16 slli.d $r4,$r4,16 add.d $r5,$r12,$r5 jr $r1 This wasn't work with GCC 14, but after r15-6490 it's supposed to work if IOR was used instead of PLUS. To fix this, add a code iterator to match IOR, XOR, and PLUS and use it instead of just IOR if we know the operands have no overlapping bits. gcc/ChangeLog: PR target/115478 * config/loongarch/loongarch.md (any_or_plus): New define_code_iterator. (bstrins_<mode>_for_ior_mask): Use any_or_plus instead of ior. (bytepick_w_<bytepick_imm>): Likewise. (bytepick_d_<bytepick_imm>): Likewise. (bytepick_d_<bytepick_imm>_rev): Likewise. gcc/testsuite/ChangeLog: PR target/115478 * gcc.target/loongarch/bytepick_shift_128.c: New test.
