[PATCH] D67127: [clang-scan-deps] add skip excluded conditional preprocessor block preprocessing optimization

[Michael Spencer via Phabricator via cfe-commits]

Bigcheese added inline comments.
Herald added a subscriber: wuzish.


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Comment at: clang/include/clang/Frontend/CompilerInstance.h:256
+  /// preprocessor.
+  void setAdditionalPPCallbacks(std::unique_ptr<PPCallbacks> PPC);
+
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This kinda sounds like it can be called multiple times.  Is there any way you can use chained pp callbacks?


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Comment at: clang/tools/clang-scan-deps/ClangScanDeps.cpp:171-177
+llvm::cl::opt<bool> SkipExcludedPPRanges(
+    "skip-excluded-pp-ranges",
+    llvm::cl::desc(
+        "Use the preprocessor optimization that skips excluded conditionals by "
+        "bumping the buffer pointer in the lexer instead of lexing the tokens  "
+        "until reaching the end directive."),
+    llvm::cl::init(true), llvm::cl::cat(DependencyScannerCategory));
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Is there any reason for this to be configurable other than for perf testing?


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D67127/new/

https://reviews.llvm.org/D67127