[llvm] annotate LLVMCloneModule for export

[andrurogerz]

Purpose

This patch is one in a series of code-mods that annotate LLVM’s public interface for export. This patch annotates the implementation of LLVMCloneModule with LLVM_ABI to match its declaration in llvm-c/Core.h. The annotation currently has no meaningful impact on the LLVM build; however, it is a prerequisite to support an LLVM Windows DLL (shared library) build.

Background

This effort is tracked in #109483. Additional context is provided in this discourse, and documentation for LLVM_ABI and related annotations is found in the LLVM repo here.

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

[llvmbot]

@llvm/pr-subscribers-llvm-transforms

Author: Andrew Rogers (andrurogerz)

Changes

Purpose

This patch is one in a series of code-mods that annotate LLVM’s public interface for export. This patch effectively annotates the implementation of LLVMCloneModule with LLVM_ABI by including llvm-c/Core.h in the implementation file. The included the function declaration is already annotated with LLVM_ABI. The annotation currently has no meaningful impact on the LLVM build; however, it is a prerequisite to support an LLVM Windows DLL (shared library) build.

Background

This effort is tracked in #109483. Additional context is provided in this discourse, and documentation for LLVM_ABI and related annotations is found in the LLVM repo here.

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

---

Full diff: https://github.com/llvm/llvm-project/pull/145570.diff

1 Files Affected:

• (modified) llvm/lib/Transforms/Utils/CloneModule.cpp (+1)

diff --git a/llvm/lib/Transforms/Utils/CloneModule.cpp b/llvm/lib/Transforms/Utils/CloneModule.cpp
index 55fb0acd39eae..ae6234c1349d6 100644
--- a/llvm/lib/Transforms/Utils/CloneModule.cpp
+++ b/llvm/lib/Transforms/Utils/CloneModule.cpp
@@ -11,6 +11,7 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "llvm-c/Core.h"
 #include "llvm/IR/DerivedTypes.h"
 #include "llvm/IR/Module.h"
 #include "llvm/Transforms/Utils/Cloning.h"

[andrurogerz]

@compnerd, @vgvassilev another simple one, thanks!

[vgvassilev]

Lgtm!

[compnerd]

I'm not sure that this is the right direction. "LLVM C" sits atop of LLVM, providing the C interface to the C++ library. This inverts that by making LLVM C a dependency of LLVM.

[andrurogerz]

I'm not sure that this is the right direction. "LLVM C" sits atop of LLVM, providing the C interface to the C++ library. This inverts that by making LLVM C a dependency of LLVM.

Ah, ok. I see what you mean. There are a few places outside of llvm-c that include llvm-c/Error.h and llvm-c/Types.h, but nothing pulls in this llvm-c/Core.h. I will resolve this by annotating the LLVMCloneModule at the implementation instead.

[compnerd]

Doesn't this only export now if you build llvm as a DLL? The use of the visibility header is fine. Bleh, I think that I missed that this was in the implementation of the llvm-c technically. If this function is not used elsewhere, I'd suggest just moving this function into a new TU in LLVM C.