607fb1bb8c
This patch ensures that we always tune for a given CPU on AArch64 targets when the user specifies the "-mtune=xyz" flag. In the AArch64Subtarget if the tune flag is unset we use the CPU value instead. I've updated the release notes here: llvm/docs/ReleaseNotes.rst and added tests here: clang/test/Driver/aarch64-mtune.c Differential Revision: https://reviews.llvm.org/D110258