https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105991
--- Comment #9 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The releases/gcc-12 branch has been updated by Roger Sayle <sa...@gcc.gnu.org>: https://gcc.gnu.org/g:6c175b3d170de2bb02b7bd45b3348eec05d28451 commit r12-8547-g6c175b3d170de2bb02b7bd45b3348eec05d28451 Author: Roger Sayle <ro...@nextmovesoftware.com> Date: Mon Jul 4 13:58:37 2022 +0100 PR target/105991: Recognize PLUS and XOR forms of rldimi in rs6000.md. This patch addresses PR target/105991 where a change to prefer representing shifts and adds at the tree-level as multiplications, causes problems for the rldimi patterns in the powerpc backend. The issue is that rs6000.md models this pattern using IOR, and some variants that have the equivalent PLUS or XOR in the RTL fail to match some *rotl<mode>4_insert patterns. This is fixed in this patch by adding a define_insn_and_split to locally canonicalize the PLUS and XOR forms to the backend's preferred IOR form. Backported from master. 2022-07-04 Roger Sayle <ro...@nextmovesoftware.com> Marek Polacek <pola...@redhat.com> Segher Boessenkool <seg...@kernel.crashing.org> Kewen Lin <li...@linux.ibm.com> gcc/ChangeLog PR target/105991 * config/rs6000/rs6000.md (rotl<mode>3_insert_3): Check that exact_log2 doesn't return -1 (or zero). (plus_xor): New code iterator. (*rotl<mode>3_insert_3_<code>): New define_insn_and_split. gcc/testsuite/ChangeLog PR target/105991 * gcc.target/powerpc/pr105991.c: New test case.
