Prefer C DILabel API for POSIX, fallback to CPP

Author: tf2spi

src/llvm_backend_debug.cpp

@@ -1302,30 +1302,75 @@ gb_internal void add_debug_info_for_global_constant_from_entity(lbGenerator *gen
 // on POSIX systems so that older solibs that don't have the C API still work.
 #ifndef _WIN32
 
-// Don't you just love a good ol' mangled name? I know I do.
-// Mangled name of "llvm::DIBuilder::createLabel(DIScope, StringRef, DIFile, unsigned, bool)"
-extern "C" LLVMMetadataRef _ZN4llvm9DIBuilder11createLabelEPNS_7DIScopeENS_9StringRefEPNS_6DIFileEjb(
+typedef LLVMMetadataRef (*LLVMDIBuilderCreateLabelPosixCPP)(
 	LLVMDIBuilderRef Builder,
 	LLVMMetadataRef Scope,
-	String Name, // Not technically proper to do, but it's ABI compatible for now...
+	// Using String here is not technically proper to do, but it's ABI
+	// compatible for the ABIs and older solib versions that we care about.
+	String Name,
 	LLVMMetadataRef File,
 	unsigned int LineNo,
 	bool AlwaysPreserve);
+typedef LLVMMetadataRef (*LLVMDIBuilderCreateLabelPosixC)(
+	LLVMDIBuilderRef Builder, LLVMMetadataRef Context, const char *Name, size_t NameLen,
+	LLVMMetadataRef File, unsigned LineNo, LLVMBool AlwaysPreserve);
+static inline LLVMMetadataRef LLVMDIBuilderCreateLabelPosix(
+	LLVMDIBuilderRef Builder, LLVMMetadataRef Context, const char *Name, size_t NameLen,
+	LLVMMetadataRef File, unsigned LineNo, LLVMBool AlwaysPreserve) {
+	static LLVMDIBuilderCreateLabelPosixC capi = nullptr;
+	static LLVMDIBuilderCreateLabelPosixCPP cppapi = nullptr;
+	if (capi == nullptr && cppapi == nullptr) {
+		capi = (LLVMDIBuilderCreateLabelPosixC)dlsym(RTLD_NEXT,
+			"LLVMDIBuilderCreateLabel");
+
+		// Mangled name of "llvm::DIBuilder::createLabel(DIScope, StringRef, DIFile, unsigned, bool)"
+		if (capi == nullptr)
+			cppapi = (LLVMDIBuilderCreateLabelPosixCPP)dlsym(RTLD_NEXT,
+				"_ZN4llvm9DIBuilder11createLabelEPNS_7DIScopeENS_9StringRefEPNS_6DIFileEjb");
+	}
+	if (capi != nullptr)
+		return capi(Builder, Context, Name, NameLen, File, LineNo, AlwaysPreserve);
+	if (cppapi != nullptr)
+		return cppapi(Builder, Context, String{(u8 *)Name, (isize)NameLen}, File, LineNo, AlwaysPreserve);
+	return nullptr;
+}
 
-// Mangled name of "llvm::DIBuilder::insertLabel(DILabel, DILocation, BasicBlock)"
-extern "C" LLVMMetadataRef _ZN4llvm9DIBuilder11insertLabelEPNS_7DILabelEPKNS_10DILocationEPNS_10BasicBlockE(
+typedef LLVMDbgRecordRef (*LLVMDIBuilderInsertLabelAtEndPosixCPP)(
+	LLVMDIBuilderRef Builder,
+	LLVMMetadataRef Label,
+	LLVMMetadataRef Location,
+	LLVMBasicBlockRef Block);
+typedef LLVMDbgRecordRef (*LLVMDIBuilderInsertLabelAtEndPosixC)(
 	LLVMDIBuilderRef Builder,
 	LLVMMetadataRef Label,
 	LLVMMetadataRef Location,
 	LLVMBasicBlockRef Block);
+static inline LLVMDbgRecordRef LLVMDIBuilderInsertLabelAtEndPosix(
+	LLVMDIBuilderRef Builder, LLVMMetadataRef LabelInfo,
+	LLVMMetadataRef Location, LLVMBasicBlockRef InsertAtEnd) {
+	static LLVMDIBuilderInsertLabelAtEndPosixC capi = nullptr;
+	static LLVMDIBuilderInsertLabelAtEndPosixCPP cppapi = nullptr;
+	if (capi == nullptr && cppapi == nullptr) {
+		capi = (LLVMDIBuilderInsertLabelAtEndPosixC)dlsym(RTLD_NEXT,
+			"LLVMDIBuilderInsertLabelAtEnd");
+
+		// Mangled name of "llvm::DIBuilder::insertLabel(DILabel, DILocation, BasicBlock)"
+		if (capi == nullptr)
+			cppapi = (LLVMDIBuilderInsertLabelAtEndPosixCPP)dlsym(RTLD_NEXT,
+				"_ZN4llvm9DIBuilder11insertLabelEPNS_7DILabelEPKNS_10DILocationEPNS_10BasicBlockE");
+	}
+	if (capi != nullptr)
+		return capi(Builder, LabelInfo, Location, InsertAtEnd);
+	if (cppapi != nullptr)
+		return cppapi(Builder, LabelInfo, Location, InsertAtEnd);
+	return nullptr;
+}
 
 #define LLVMDIBuilderCreateLabel(Builder, Context, Name, NameLen, File, LineNo, AlwaysPreserve) \
-	_ZN4llvm9DIBuilder11createLabelEPNS_7DIScopeENS_9StringRefEPNS_6DIFileEjb( \
-		Builder, Context, String{(u8 *)Name,(isize)NameLen}, File, LineNo, AlwaysPreserve)
+	LLVMDIBuilderCreateLabelPosix(Builder, Context, Name, NameLen, File, LineNo, AlwaysPreserve)
 
 #define LLVMDIBuilderInsertLabelAtEnd(Builder, LabelInfo, Location, InsertAtEnd) \
-	_ZN4llvm9DIBuilder11insertLabelEPNS_7DILabelEPKNS_10DILocationEPNS_10BasicBlockE( \
-		Builder, LabelInfo, Location, InsertAtEnd)
+	LLVMDIBuilderInsertLabelAtEndPosix(Builder, LabelInfo, Location, InsertAtEnd)
 
 #endif
 gb_internal void lb_add_debug_label(lbProcedure *p, Ast *label, lbBlock *target) {