Update llvm::Registry to work for LLVM shared library builds on windows #109024
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@llvm/pr-subscribers-clang @llvm/pr-subscribers-llvm-ir Author: Thomas Fransham (fsfod) ChangesThis 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. Full diff: https://github.com/llvm/llvm-project/pull/109024.diff 6 Files Affected:
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..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.
@@ -134,26 +140,29 @@ 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
|
|
@llvm/pr-subscribers-llvm-support Author: Thomas Fransham (fsfod) ChangesThis 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. Full diff: https://github.com/llvm/llvm-project/pull/109024.diff 6 Files Affected:
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..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.
@@ -134,26 +140,29 @@ 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
|
compnerd
reviewed
Sep 18, 2024
| @@ -189,19 +190,23 @@ | |||
| #define LLVM_TEMPLATE_ABI __declspec(dllimport) | |||
| #define LLVM_EXPORT_TEMPLATE | |||
| #endif | |||
| #define LLVM_ABI_EXPORT __declspec(dllexport) | |||
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Why is this being added? I'm weary of any macro that is always export only because the value needs to switch between the definition and reference.
There was a problem hiding this comment.
Its macro I mentioned earlier initial explanation about being used in Clang and LLVM, it should never be used for things that could be references.
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I think this is subtle enough that we may need some documentation comments explaining when and how someone should use this. (Most reviewers aren't going to be well-versed in how shared libraries work on Windows.)
There was a problem hiding this comment.
I added a comment to try and explains its use and behaviour.
| @@ -189,19 +190,23 @@ | |||
| #define LLVM_TEMPLATE_ABI __declspec(dllimport) | |||
| #define LLVM_EXPORT_TEMPLATE | |||
| #endif | |||
| #define LLVM_ABI_EXPORT __declspec(dllexport) | |||
There was a problem hiding this comment.
I think this is subtle enough that we may need some documentation comments explaining when and how someone should use this. (Most reviewers aren't going to be well-versed in how shared libraries work on Windows.)
Open
32 tasks
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@AaronBallman I've added some missing extern template entries for Clang. clang-tools-extra also needs some idk if you ok adding them to this PR as well. |
|
@john-brawn-arm This may be hard to remember, but this a path you've tread before could the LLVM_INSTANTIATE_REGISTRY just be changed to a fulll class explicit template instantiation? |
It looks like the approach you're going for is:
Yes, I think LLVM_INSTANTIATE_REGISTRY can just be a explicit instantiation of the template class, as using extern template in the header gets rid of the reason that the current implementation exists. |
|
✅ With the latest revision this PR passed the C/C++ code formatter. |
AaronBallman
reviewed
Oct 8, 2024
It won't be able to pass until #108276 is merged. |
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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.
…egistry 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
Co-authored-by: Saleem Abdulrasool <compnerd@compnerd.org>
…n and CompilationDatabasePlugin registry in clang
…explicit instantiation
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vgvassilev
approved these changes
Oct 16, 2024
|
LLVM Buildbot has detected a new failure on builder Full details are available at: https://lab.llvm.org/buildbot/#/builders/89/builds/8505 Here is the relevant piece of the build log for the reference |
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…ws (llvm#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 llvm#108276 --------- Co-authored-by: Saleem Abdulrasool <compnerd@compnerd.org>
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…on windows (llvm#109024)" This reverts commit 00cd1a0. This effectively reverts llvm#109024
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…on windows' (llvm#109024) Fix missing extern templates for llvm::Registry use in other projects of llvm 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 to just be a full explicit template instantiation. This is part of the work to enable LLVM_BUILD_LLVM_DYLIB and LLVM plugins on window.
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…ws (llvm#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 llvm#108276 --------- Co-authored-by: Saleem Abdulrasool <compnerd@compnerd.org>
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…on windows (llvm#109024)" This reverts commit 00cd1a0. This effectively reverts llvm#109024
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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