4f8c961924
MacOS 15.0 and iOS 18.0 added a new sysctl to fetch a bitvector of all the hw.optional.arm.FEAT_*'s in one go. Using this has a perf advantage over doing multiple round-trips to the kernel and back, but since it's not present in older oses, we still need the slow fallback.
Compiler-RT ================================ This directory and its subdirectories contain source code for the compiler support routines. Compiler-RT is open source software. You may freely distribute it under the terms of the license agreement found in LICENSE.txt. ================================