llvm-project

a070a156 - [libc] Add config option to use memory builtin functions. (#197977)

[libc] Add config option to use memory builtin functions. (#197977) Add a new CMake and C++ definition configuration option `LIBC_CONF_USE_MEM_BUILTINS` to allow users to use compiler builtins for memory utility functions (memcpy, memset, memmove, memcmp, and bcmp) instead of LLVM libc's internal implementations. Main use-cases are: - when users want to bring their own memory functions implementations that are highly optimized for their targets - improve portability by providing a fallback for targets for which LLVM libc does not have memory utility implementations yet - to be used for libc/shared functions and their testings, as we expect libc/shared functions to provide their own memory functions.