https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115659
--- Comment #12 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Kewen Lin <li...@gcc.gnu.org>: https://gcc.gnu.org/g:f379596e0ba99df249d6e8b3f2e66edfcea916fe commit r15-1890-gf379596e0ba99df249d6e8b3f2e66edfcea916fe Author: Kewen Lin <li...@linux.ibm.com> Date: Mon Jul 8 00:14:59 2024 -0500 isel: Fold more in gimple_expand_vec_cond_expr with andc and iorc [PR115659] As PR115659 shows, assuming c = x CMP y, there are some folding chances for patterns r = c ? 0/z : z/-1: - for r = c ? 0 : z, it can be folded into r = ~c & z. - for r = c ? z : -1, it can be folded into r = ~c | z. But BIT_AND/BIT_IOR applied on one BIT_NOT operand is a compound operation, it's arguable to consider it beats vector selection. So this patch is to introduce new optabs andc, iorc and its corresponding internal functions BIT_{ANDC,IORC}, and if targets defines such optabs for vector modes, it means targets support these hardware insns and should be not worse than vector selection. PR tree-optimization/115659 gcc/ChangeLog: * doc/md.texi: Document andcm3 and iorcm3. * gimple-isel.cc (gimple_expand_vec_cond_expr): Add more foldings for patterns x CMP y ? 0 : z and x CMP y ? z : -1. * internal-fn.def (BIT_ANDC): New internal function. (BIT_IORC): Likewise. * optabs.def (andc, iorc): New optab.
