[clang] [llvm] Update llvm::Registry to work for LLVM shared library builds on windows (PR #109024)
Thomas Fransham via cfe-commits
cfe-commits at lists.llvm.org
Tue Sep 17 10:54:15 PDT 2024
https://github.com/fsfod created https://github.com/llvm/llvm-project/pull/109024
This is part of the effort to support for enabling plugins on windows by adding better support for building llvm and clang as a DLL.
Since windows doesn't implicitly import and merge exported symbols across shared libraries like other platforms we need to explicitly add a extern template declaration for each instantiation of llvm::Registry to force the registry symbols to be dllimport'ed.
I've added a new visibility macro that doesn't switch between dllimport and dllexport on windows since the existing macro would be in the wrong mode for llvm::Registry's declared in Clang. This PR also depends Clang symbol visibility macros that will be added by #108276
>From fcb6837e5c6ff48bf261bae9d3cedda55da89a7e Mon Sep 17 00:00:00 2001
From: Thomas Fransham <tfransham at gmail.com>
Date: Wed, 28 Aug 2024 16:08:52 +0100
Subject: [PATCH 1/2] Update llvm::Registry to work for LLVM shared library
builds on windows
Windows doesn't implicitly import and merge exported symbols across shared libraries
like Linux does so we need to explicitly export/import each instantiation of llvm::Registry.
Updated LLVM_INSTANTIATE_REGISTRY macro to export Registry::add_node and
Registry::begin() and add extern template declarations for the all instantiations of llvm::Registry.
---
clang/include/clang/Basic/ParsedAttrInfo.h | 5 +++
.../clang/Frontend/FrontendPluginRegistry.h | 5 +++
llvm/include/llvm/CodeGen/GCMetadataPrinter.h | 2 +
llvm/include/llvm/IR/GCStrategy.h | 2 +
llvm/include/llvm/Support/Compiler.h | 5 +++
llvm/include/llvm/Support/Registry.h | 43 ++++++++++---------
6 files changed, 42 insertions(+), 20 deletions(-)
diff --git a/clang/include/clang/Basic/ParsedAttrInfo.h b/clang/include/clang/Basic/ParsedAttrInfo.h
index 537d8f3391d589..2b82dd3b43d133 100644
--- a/clang/include/clang/Basic/ParsedAttrInfo.h
+++ b/clang/include/clang/Basic/ParsedAttrInfo.h
@@ -17,6 +17,7 @@
#include "clang/Basic/AttrSubjectMatchRules.h"
#include "clang/Basic/AttributeCommonInfo.h"
+#include "clang/Support/Compiler.h"
#include "llvm/ADT/ArrayRef.h"
#include "llvm/Support/Registry.h"
#include <climits>
@@ -165,4 +166,8 @@ const std::list<std::unique_ptr<ParsedAttrInfo>> &getAttributePluginInstances();
} // namespace clang
+namespace llvm {
+extern template class CLANG_TEMPLATE_ABI llvm::Registry<clang::ParsedAttrInfo>;
+} // namespace llvm
+
#endif // LLVM_CLANG_BASIC_PARSEDATTRINFO_H
diff --git a/clang/include/clang/Frontend/FrontendPluginRegistry.h b/clang/include/clang/Frontend/FrontendPluginRegistry.h
index 810578534acb45..5eea9c2fd89a32 100644
--- a/clang/include/clang/Frontend/FrontendPluginRegistry.h
+++ b/clang/include/clang/Frontend/FrontendPluginRegistry.h
@@ -14,6 +14,7 @@
#define LLVM_CLANG_FRONTEND_FRONTENDPLUGINREGISTRY_H
#include "clang/Frontend/FrontendAction.h"
+#include "clang/Support/Compiler.h"
#include "llvm/Support/Registry.h"
namespace clang {
@@ -23,4 +24,8 @@ using FrontendPluginRegistry = llvm::Registry<PluginASTAction>;
} // namespace clang
+namespace llvm {
+extern template class CLANG_TEMPLATE_ABI Registry<clang::PluginASTAction>;
+} // namespace llvm
+
#endif // LLVM_CLANG_FRONTEND_FRONTENDPLUGINREGISTRY_H
diff --git a/llvm/include/llvm/CodeGen/GCMetadataPrinter.h b/llvm/include/llvm/CodeGen/GCMetadataPrinter.h
index f9527c9f8752e9..9d421be8313f01 100644
--- a/llvm/include/llvm/CodeGen/GCMetadataPrinter.h
+++ b/llvm/include/llvm/CodeGen/GCMetadataPrinter.h
@@ -34,6 +34,8 @@ class StackMaps;
/// defaults from Registry.
using GCMetadataPrinterRegistry = Registry<GCMetadataPrinter>;
+extern template class LLVM_TEMPLATE_ABI Registry<GCMetadataPrinter>;
+
/// GCMetadataPrinter - Emits GC metadata as assembly code. Instances are
/// created, managed, and owned by the AsmPrinter.
class GCMetadataPrinter {
diff --git a/llvm/include/llvm/IR/GCStrategy.h b/llvm/include/llvm/IR/GCStrategy.h
index 3186465f001812..cbfbe23aaa0683 100644
--- a/llvm/include/llvm/IR/GCStrategy.h
+++ b/llvm/include/llvm/IR/GCStrategy.h
@@ -141,6 +141,8 @@ class GCStrategy {
/// GCMetadataPrinterRegistery as well.
using GCRegistry = Registry<GCStrategy>;
+extern template class LLVM_TEMPLATE_ABI Registry<GCStrategy>;
+
/// Lookup the GCStrategy object associated with the given gc name.
std::unique_ptr<GCStrategy> getGCStrategy(const StringRef Name);
diff --git a/llvm/include/llvm/Support/Compiler.h b/llvm/include/llvm/Support/Compiler.h
index 1d2d751d4dc11a..e893734b81fb7d 100644
--- a/llvm/include/llvm/Support/Compiler.h
+++ b/llvm/include/llvm/Support/Compiler.h
@@ -179,6 +179,7 @@
#define LLVM_ABI
#define LLVM_TEMPLATE_ABI
#define LLVM_EXPORT_TEMPLATE
+#define LLVM_ABI_EXPORT
#elif defined(_WIN32) && !defined(__MINGW32__)
#if defined(LLVM_EXPORTS)
#define LLVM_ABI __declspec(dllexport)
@@ -189,19 +190,23 @@
#define LLVM_TEMPLATE_ABI __declspec(dllimport)
#define LLVM_EXPORT_TEMPLATE
#endif
+#define LLVM_ABI_EXPORT __declspec(dllexport)
#elif defined(__ELF__) || defined(__MINGW32__) || defined(_AIX)
#define LLVM_ABI LLVM_ATTRIBUTE_VISIBILITY_DEFAULT
#define LLVM_TEMPLATE_ABI LLVM_ATTRIBUTE_VISIBILITY_DEFAULT
#define LLVM_EXPORT_TEMPLATE
+#define LLVM_ABI_EXPORT LLVM_ATTRIBUTE_VISIBILITY_DEFAULT
#elif defined(__MACH__) || defined(__WASM__)
#define LLVM_ABI LLVM_ATTRIBUTE_VISIBILITY_DEFAULT
#define LLVM_TEMPLATE_ABI
#define LLVM_EXPORT_TEMPLATE
+#define LLVM_ABI_EXPORT LLVM_ATTRIBUTE_VISIBILITY_DEFAULT
#endif
#else
#define LLVM_ABI
#define LLVM_TEMPLATE_ABI
#define LLVM_EXPORT_TEMPLATE
+#define LLVM_ABI_EXPORT
#endif
#define LLVM_C_ABI LLVM_ABI
#endif
diff --git a/llvm/include/llvm/Support/Registry.h b/llvm/include/llvm/Support/Registry.h
index 5bb6a254a47f4c..2dcbe0f2a28208 100644
--- a/llvm/include/llvm/Support/Registry.h
+++ b/llvm/include/llvm/Support/Registry.h
@@ -134,26 +134,29 @@ namespace llvm {
/// strictly speaking that's not allowed by the C++ standard (we would need to
/// have explicit specialization declarations in all translation units where the
/// specialization is used) so we don't.
-#define LLVM_INSTANTIATE_REGISTRY(REGISTRY_CLASS) \
- namespace llvm { \
- template<typename T> typename Registry<T>::node *Registry<T>::Head = nullptr;\
- template<typename T> typename Registry<T>::node *Registry<T>::Tail = nullptr;\
- template<typename T> \
- void Registry<T>::add_node(typename Registry<T>::node *N) { \
- if (Tail) \
- Tail->Next = N; \
- else \
- Head = N; \
- Tail = N; \
- } \
- template<typename T> typename Registry<T>::iterator Registry<T>::begin() { \
- return iterator(Head); \
- } \
- template REGISTRY_CLASS::node *Registry<REGISTRY_CLASS::type>::Head; \
- template REGISTRY_CLASS::node *Registry<REGISTRY_CLASS::type>::Tail; \
- template \
- void Registry<REGISTRY_CLASS::type>::add_node(REGISTRY_CLASS::node*); \
- template REGISTRY_CLASS::iterator Registry<REGISTRY_CLASS::type>::begin(); \
+#define LLVM_INSTANTIATE_REGISTRY(REGISTRY_CLASS) \
+ namespace llvm { \
+ template <typename T> \
+ typename Registry<T>::node *Registry<T>::Head = nullptr; \
+ template <typename T> \
+ typename Registry<T>::node *Registry<T>::Tail = nullptr; \
+ template <typename T> \
+ void Registry<T>::add_node(typename Registry<T>::node *N) { \
+ if (Tail) \
+ Tail->Next = N; \
+ else \
+ Head = N; \
+ Tail = N; \
+ } \
+ template <typename T> typename Registry<T>::iterator Registry<T>::begin() { \
+ return iterator(Head); \
+ } \
+ template REGISTRY_CLASS::node *Registry<REGISTRY_CLASS::type>::Head; \
+ template REGISTRY_CLASS::node *Registry<REGISTRY_CLASS::type>::Tail; \
+ template LLVM_ABI_EXPORT void \
+ Registry<REGISTRY_CLASS::type>::add_node(REGISTRY_CLASS::node *); \
+ template LLVM_ABI_EXPORT REGISTRY_CLASS::iterator \
+ Registry<REGISTRY_CLASS::type>::begin(); \
}
#endif // LLVM_SUPPORT_REGISTRY_H
>From d0974bfb8ff6f1b993bc563f899a5313d26b13a8 Mon Sep 17 00:00:00 2001
From: Thomas Fransham <tfransham at gmail.com>
Date: Mon, 16 Sep 2024 16:00:51 +0100
Subject: [PATCH 2/2] Workaround 20 year old MSVC compiler bug for static
fields of llvm::Registry
Fixes Tail': member of dll interface class may not be declared with dll interface
https://developercommunity.visualstudio.com/t/c2487-in-dllexport-class-with-static-members/69878
---
llvm/include/llvm/Support/Registry.h | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/llvm/include/llvm/Support/Registry.h b/llvm/include/llvm/Support/Registry.h
index 2dcbe0f2a28208..837cd1237fd38f 100644
--- a/llvm/include/llvm/Support/Registry.h
+++ b/llvm/include/llvm/Support/Registry.h
@@ -53,7 +53,13 @@ namespace llvm {
Registry() = delete;
friend class node;
- static node *Head, *Tail;
+ // These must be must two separate declarations to workaround a 20 year
+ // old MSVC bug with dllexport and multiple static fields in the same
+ // declaration causing error C2487 "member of dll interface class may not
+ // be declared with dll interface".
+ // https://developercommunity.visualstudio.com/t/c2487-in-dllexport-class-with-static-members/69878
+ static node *Head;
+ static node *Tail;
public:
/// Node in linked list of entries.
More information about the cfe-commits
mailing list