https://gcc.gnu.org/bugzilla/show_bug.cgi?id=57492
--- Comment #7 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Soumya AR <soum...@gcc.gnu.org>: https://gcc.gnu.org/g:5a674367c6da870184f3bdb7ec110b96aa91bb2b commit r15-5201-g5a674367c6da870184f3bdb7ec110b96aa91bb2b Author: Soumya AR <soum...@nvidia.com> Date: Wed Nov 13 15:41:15 2024 +0530 Match: Fold pow calls to ldexp when possible [PR57492] This patch transforms the following POW calls to equivalent LDEXP calls, as discussed in PR57492: powi (powof2, i) -> ldexp (1.0, i * log2 (powof2)) powof2 * ldexp (x, i) -> ldexp (x, i + log2 (powof2)) a * ldexp(1., i) -> ldexp (a, i) This is especially helpful for SVE architectures as LDEXP calls can be implemented using the FSCALE instruction, as seen in the following patch: https://gcc.gnu.org/g:9b2915d95d855333d4d8f66b71a75f653ee0d076 SPEC2017 was run with this patch, while there are no noticeable improvements, there are no non-noise regressions either. The patch was bootstrapped and regtested on aarch64-linux-gnu, no regression. Signed-off-by: Soumya AR <soum...@nvidia.com> gcc/ChangeLog: PR target/57492 * match.pd: Added patterns to fold calls to pow to ldexp and optimize specific ldexp calls. gcc/testsuite/ChangeLog: PR target/57492 * gcc.dg/tree-ssa/ldexp.c: New test. * gcc.dg/tree-ssa/pow-to-ldexp.c: New test.
