[clang] [clang][DependencyScanning] Implementing a Streaming Style API for By-name Scanning (PR #206800)

[Jan Svoboda via cfe-commits]

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+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_DEPENDENCYSCANNING_COMPILERINSTANCEWITHCONTEXT_H
+#define LLVM_CLANG_DEPENDENCYSCANNING_COMPILERINSTANCEWITHCONTEXT_H
+
+#include "clang/DependencyScanning/DependencyScanningWorker.h"
+
+namespace clang {
+namespace dependencies {
+class CompilerInstanceWithContext {
+  // Context
+  DependencyScanningWorker &Worker;
+  llvm::StringRef CWD;
+  std::vector<std::string> CommandLine;
+
+  // Context - compiler invocation
+  std::unique_ptr<CompilerInvocation> OriginalInvocation;
+
+  // Context - output options
+  std::unique_ptr<DependencyOutputOptions> OutputOpts;
+
+  // Context - stable directory handling
+  llvm::SmallVector<StringRef> StableDirs;
+  PrebuiltModulesAttrsMap PrebuiltModuleASTMap;
+
+  // Context - used by AsyncScan's prescan pass
+  IntrusiveRefCntPtr<llvm::vfs::FileSystem> ScanFS;
+
+  // Compiler Instance
+  std::unique_ptr<CompilerInstance> CIPtr;
+
+  // Source location offset.
+  int32_t SrcLocOffset = 0;
+
+  CompilerInstanceWithContext(DependencyScanningWorker &Worker, StringRef CWD,
+                              ArrayRef<std::string> CMD)
+      : Worker(Worker), CWD(CWD), CommandLine(CMD.begin(), CMD.end()) {}
+
+  bool initialize(
+      DependencyActionController &Controller,
+      std::unique_ptr<DiagnosticsEngineWithDiagOpts> DiagEngineWithDiagOpts,
+      IntrusiveRefCntPtr<llvm::vfs::FileSystem> OverlayFS);
+
+  bool initializeScanInstance(DependencyActionController &Controller,
+                              DiagnosticConsumer *DiagConsumer);
+
+  bool prescanModulesAsync(AsyncModuleCompiles &Compiles,
+                           DependencyActionController &Controller);
+
+public:
+  /// @brief Initialize the tool's compiler instance from the cc1 commandline.
+  /// @param Worker The dependency scanning worker to initialize the compiler
+  ///        instance.
+  /// @param CWD The current working directory.
+  /// @param CC1CommandLine A cc1 command.
+  /// @param DiagEngineWithDiagOpts The diagnostic engine used during scan.
+  /// @param OverlayFS An overlay FS containing the input file, which may be
+  ///        from an in-memory buffer.
+  /// @param Controller A dependency action controller to gather some results.
+  static std::optional<CompilerInstanceWithContext>
+  initializeFromCC1Commandline(
+      DependencyScanningWorker &Worker, StringRef CWD,
+      ArrayRef<std::string> CC1CommandLine,
+      std::unique_ptr<DiagnosticsEngineWithDiagOpts> DiagEngineWithDiagOpts,
+      IntrusiveRefCntPtr<llvm::vfs::FileSystem> OverlayFS,
+      DependencyActionController &Controller);
+
+  bool computeDependencies(StringRef ModuleName, DependencyConsumer &Consumer,
+                           DependencyActionController &Controller);
+
+  // MaxNumOfQueries is the upper limit of the number of names the by-name
+  // scanning API (computeDependencies) can support after a
+  // CompilerInstanceWithContext is initialized. At the time of this commit, the
+  // estimated number of total unique importable names is around 3000 from
+  // Apple's SDKs. We usually import them in parallel, so it is unlikely that
+  // all names are all scanned by the same dependency scanning worker. Therefore
+  // the 64k (20x bigger than our estimate) size is sufficient to hold the
+  // unique source locations to report diagnostics per worker.
+  static const int32_t MaxNumOfQueries = 1 << 16;
+
+  std::shared_ptr<ModuleDepCollector>
+  scanTranslationUnit(DependencyConsumer &Consumer,
+                      DependencyActionController &Controller);
+
+  bool applyAndReport(ModuleDepCollector &MDC,
+                      CompilerInvocation &ModuleInvocation,
+                      DependencyConsumer &Consumer,
+                      DependencyActionController &Controller,
+                      StringRef Executable);
+};
+} // namespace dependencies
+} // namespace clang
+
+#endif
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jansvoboda11 wrote:

Missing newline.

https://github.com/llvm/llvm-project/pull/206800