[clang-tools-extra] [clangd] [Modules] Support Reusable Modules Builder (PR #106683)

[kadir çetinkaya via cfe-commits]

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@@ -228,54 +223,30 @@ class StandalonePrerequisiteModules : public PrerequisiteModules {
     return BuiltModuleNames.contains(ModuleName);
   }
 
-  void addModuleFile(llvm::StringRef ModuleName,
-                     llvm::StringRef ModuleFilePath) {
-    RequiredModules.emplace_back(ModuleName, ModuleFilePath);
-    BuiltModuleNames.insert(ModuleName);
+  void addModuleFile(std::shared_ptr<ModuleFile> BMI) {
+    BuiltModuleNames.insert(BMI->ModuleName);
+    RequiredModules.emplace_back(std::move(BMI));
   }
 
 private:
-  llvm::SmallVector<ModuleFile, 8> RequiredModules;
+  mutable llvm::SmallVector<std::shared_ptr<ModuleFile>, 8> RequiredModules;
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kadircet wrote:

why do we need to make this mutable?

also let's store a `std::shared_ptr<const ModuleFile>` instead (and update rest of the places to make sure a module file is never mutated after construction)

https://github.com/llvm/llvm-project/pull/106683