[clang] [clang][DependencyScanning] Implementation of `CompilerInstanceWithContext` to Improve By-Name Queries (PR #164345)

[Qiongsi Wu via cfe-commits]

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@@ -150,6 +151,54 @@ std::shared_ptr<ModuleDepCollector> initializeScanInstanceDependencyCollector(
     DependencyActionController &Controller,
     PrebuiltModulesAttrsMap PrebuiltModulesASTMap,
     llvm::SmallVector<StringRef> &StableDirs);
+
+class CompilerInstanceWithContext {
+  // Context
+  DependencyScanningWorker &Worker;
+  llvm::StringRef CWD;
+  std::vector<std::string> CommandLine;
+  static const uint64_t MAX_NUM_NAMES = (1 << 12);
+  static const std::string FakeFileBuffer;
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qiongsiwu wrote:

I tested out a few scenarios, and it seems that things work all right with even an empty string buffer, so I removed this fake file buffer altogether. 

https://github.com/llvm/llvm-project/pull/164345