The patch primarily cleans up some incorrect includes. The `LIBC_INLINE`
macro is defined in `attributes.h`, not `config.h`. There appears to be
no need to change the CMake and Bazel build files.
Summary:
The GPU build is special in the sense that we always know that
up-to-date `clang` is always going to be the compiler. This allows us to
rely directly on builtins, which allow us to push a lot of this
complexity into the backend. Backend implementations are favored on
the GPU because it allows us to do a lot more target specific
optimizations. This patch changes over the common memory functions to
use builtin versions when building for AMDGPU or NVPTX.
This patch mostly renames files so it better reflects the function they declare.
Reviewed By: michaelrj
Differential Revision: https://reviews.llvm.org/D155607
