2 Commits

Author SHA1 Message Date
Siva Chandra Reddy
740db97ad1 [libc][NFC] Simplify how the definiton of NULL macro is added to string.h.
We do not list macro definitions in api.td files anymore. Not all macros
definitions have been moved out. This change moves the definition of the
NULL macro out.

Reviewed By: lntue, jhuber6

Differential Revision: https://reviews.llvm.org/D140376
2022-12-20 19:14:27 +00:00
Joseph Huber
55151e138d [libc] Add initial support for a libc implementation for the GPU
This patch contains the initial support for building LLVM's libc as a
target for the GPU. Currently this only supports a handful of very basic
functions that can be implemented without an operating system. The GPU
code is build using the existing OpenMP toolchain. This allows us to
minimally change the existing codebase and get a functioning static
library. This patch allows users to create a static library called
`libcgpu.a` that contains fat binaries containing device IR.

Current limitations are the lack of test support and the fact that only
one target OS can be built at a time. That is, the user cannot get a
`libc` for Linux and one for the GPU simultaneously.

This introduces two new CMake variables to control the behavior
`LLVM_LIBC_TARET_OS` is exported so the user can now specify it to equal
`"gpu"`. `LLVM_LIBC_GPU_ARCHITECTURES` is also used to configure how
many targets to build for at once.

Depends on D138607

Reviewed By: sivachandra

Differential Revision: https://reviews.llvm.org/D138608
2022-11-29 14:51:54 -06:00