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.

Author: fsfod

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>
@@ -175,4 +176,8 @@ 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

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

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 {

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);
 

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

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