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  for (std::string OptionName : {
#define GET_CHECKER_OPTIONS
#define CHECKER_OPTION(TYPE, CHECKER, OPTION_NAME, DESCRIPTION, DEFAULT,       \
                       RELEASE, HIDDEN)                                        \
  Twine(AnalyzerCheckNamePrefix).concat(CHECKER ":" OPTION_NAME).str(),

#include "clang/StaticAnalyzer/Checkers/Checkers.inc"
#undef CHECKER_OPTION
#undef GET_CHECKER_OPTIONS
       }) {
    Result.Options.insert(OptionName);
  }

This code is doing a lot of unnecessary work at runtime. For each of the (currently) 59 checker options, it runs Twine(AnalyzerCheckNamePrefix).concat(CHECKER ":" OPTION_NAME).str(),, which allocates a string (all of this is unrolled, leading to code bloat). Then it copies all those strings (because std::string OptionName, not const std::string& OptionName). All of this can be done at compile time!

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llvmbot commented Jul 7, 2025

@llvm/pr-subscribers-clang-tools-extra

@llvm/pr-subscribers-clang-tidy

Author: Victor Chernyakin (localspook)

Changes
  for (std::string OptionName : {
#define GET_CHECKER_OPTIONS
#define CHECKER_OPTION(TYPE, CHECKER, OPTION_NAME, DESCRIPTION, DEFAULT,       \
                       RELEASE, HIDDEN)                                        \
  Twine(AnalyzerCheckNamePrefix).concat(CHECKER ":" OPTION_NAME).str(),

#include "clang/StaticAnalyzer/Checkers/Checkers.inc"
#undef CHECKER_OPTION
#undef GET_CHECKER_OPTIONS
       }) {
    Result.Options.insert(OptionName);
  }

This code is doing a lot of unnecessary work at runtime. For each of the (currently) 59 checker options, it runs Twine(AnalyzerCheckNamePrefix).concat(CHECKER ":" OPTION_NAME).str(),, which allocates a string (all of this is unrolled, leading to code bloat). Then it copies all those strings (because std::string OptionName, not const std::string& OptionName). All of this can be done at compile time!


Full diff: https://github.com/llvm/llvm-project/pull/147406.diff

1 Files Affected:

  • (modified) clang-tools-extra/clang-tidy/ClangTidy.cpp (+6-5)
diff --git a/clang-tools-extra/clang-tidy/ClangTidy.cpp b/clang-tools-extra/clang-tidy/ClangTidy.cpp
index f4ab93b51f4a7..815033c2e5175 100644
--- a/clang-tools-extra/clang-tidy/ClangTidy.cpp
+++ b/clang-tools-extra/clang-tidy/ClangTidy.cpp
@@ -668,18 +668,19 @@ getAllChecksAndOptions(bool AllowEnablingAnalyzerAlphaCheckers) {
     Buffer.append(AnalyzerCheck);
     Result.Checks.insert(Buffer);
   }
-  for (std::string OptionName : {
+
+  static constexpr llvm::StringLiteral OptionNames[] = {
 #define GET_CHECKER_OPTIONS
 #define CHECKER_OPTION(TYPE, CHECKER, OPTION_NAME, DESCRIPTION, DEFAULT,       \
                        RELEASE, HIDDEN)                                        \
-  Twine(AnalyzerCheckNamePrefix).concat(CHECKER ":" OPTION_NAME).str(),
+  "clang-analyzer-" CHECKER ":" OPTION_NAME,
 
 #include "clang/StaticAnalyzer/Checkers/Checkers.inc"
 #undef CHECKER_OPTION
 #undef GET_CHECKER_OPTIONS
-       }) {
-    Result.Options.insert(OptionName);
-  }
+  };
+
+  Result.Options.insert_range(OptionNames);
 #endif // CLANG_TIDY_ENABLE_STATIC_ANALYZER
 
   Context.setOptionsCollector(&Result.Options);

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vbvictor commented Jul 8, 2025

Please make the title more detailed about what you changed exactly.

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LGTM

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lgtm

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lgtm

@HerrCai0907 HerrCai0907 changed the title [clang-tidy][NFC] Do more work at compile time [clang-tidy][NFC] concat static-analyzer nam at compilation time Jul 9, 2025
@HerrCai0907 HerrCai0907 changed the title [clang-tidy][NFC] concat static-analyzer nam at compilation time [clang-tidy][NFC] concat static-analyzer name at compilation time Jul 9, 2025
@HerrCai0907 HerrCai0907 merged commit b041a58 into llvm:main Jul 9, 2025
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@localspook Congratulations on having your first Pull Request (PR) merged into the LLVM Project!

Your changes will be combined with recent changes from other authors, then tested by our build bots. If there is a problem with a build, you may receive a report in an email or a comment on this PR.

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5 participants