Andrew Rogers 0580563299
[llvm] annotate interfaces in llvm-c for DLL export (#141701)
## Purpose

This patch is one in a series of code-mods that annotate LLVM’s public
interface for export. This patch annotates the `llvm-c` interface with a
new `LLVM_C_ABI` annotation, which behaves like the `LLVM_ABI`. This
annotation currently has no meaningful impact on the LLVM build;
however, it is a prerequisite to support an LLVM Windows DLL (shared
library) build.

## Overview

1. Add a new `llvm-c/Visibility.h` header file that defines a new
`LLVM_C_ABI` macro. The macro resolves to the proper DLL export/import
annotation on Windows and a "default" visibility annotation elsewhere.
2. Add a new `LLVM_ENABLE_LLVM_C_EXPORT_ANNOTATIONS` `#cmakedefine` that
is used to gate the definition of `LLVM_C_ABI`.
3. Remove the existing `LLVM_C_ABI` definition from
`llvm/Support/Compiler.h`. Update the small number of `LLVM_C_ABI`
references to get it from the new `llvm-c/Visibility.h` header.
4. Code-mod annotate the public `llvm-c` interface using the [Interface
Definition Scanner (IDS)](https://github.com/compnerd/ids) tool.
5. Format the changes with `clang-format`.

## Background

This effort is tracked in #109483. Additional context is provided in
[this
discourse](https://discourse.llvm.org/t/psa-annotating-llvm-public-interface/85307),
and documentation for `LLVM_ABI` and related annotations is found in the
LLVM repo
[here](https://github.com/llvm/llvm-project/blob/main/llvm/docs/InterfaceExportAnnotations.rst).

## Validation

Local builds and tests to validate cross-platform compatibility. This
included llvm, clang, and lldb on the following configurations:

- Windows with MSVC
- Windows with Clang
- Linux with GCC
- Linux with Clang
- Darwin with Clang
2025-07-08 08:50:21 -07:00

54 lines
2.4 KiB
C

/*===------- llvm-c/LLJITUtils.h - Advanced LLJIT features --------*- C -*-===*\
|* *|
|* Part of the LLVM Project, under the Apache License v2.0 with LLVM *|
|* Exceptions. *|
|* See https://llvm.org/LICENSE.txt for license information. *|
|* SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception *|
|* *|
|*===----------------------------------------------------------------------===*|
|* *|
|* This header declares the C interface for extra utilities to be used with *|
|* the LLJIT class from the llvm-c/LLJIT.h header. It requires to following *|
|* link libraries in addition to libLLVMOrcJIT.a: *|
|* - libLLVMOrcDebugging.a *|
|* *|
|* Many exotic languages can interoperate with C code but have a harder time *|
|* with C++ due to name mangling. So in addition to C, this interface enables *|
|* tools written in such languages. *|
|* *|
|* Note: This interface is experimental. It is *NOT* stable, and may be *|
|* changed without warning. Only C API usage documentation is *|
|* provided. See the C++ documentation for all higher level ORC API *|
|* details. *|
|* *|
\*===----------------------------------------------------------------------===*/
#ifndef LLVM_C_LLJITUTILS_H
#define LLVM_C_LLJITUTILS_H
#include "llvm-c/LLJIT.h"
#include "llvm-c/Visibility.h"
LLVM_C_EXTERN_C_BEGIN
/**
* @defgroup LLVMCExecutionEngineLLJITUtils LLJIT Utilities
* @ingroup LLVMCExecutionEngineLLJIT
*
* @{
*/
/**
* Install the plugin that submits debug objects to the executor. Executors must
* expose the llvm_orc_registerJITLoaderGDBWrapper symbol.
*/
LLVM_C_ABI LLVMErrorRef LLVMOrcLLJITEnableDebugSupport(LLVMOrcLLJITRef J);
/**
* @}
*/
LLVM_C_EXTERN_C_END
#endif /* LLVM_C_LLJITUTILS_H */