[Analyzer] getRegisteredCheckers(): handle debug checkers too.

[lebedev.ri]

Summary

I would like to be able to trigger these debug checkers from clang-tidy, as a follow-up patch for D46159

[alexfh]

What's the use case for debug CSA checkers in clang-tidy?

[NoQ]

It seems that you're using debug checkers of the analyzer to gain some free tools for exploring the source code (such as displaying a call graph) for free, right?

I believe we could also benefit from a method of extracting the analyzer's clang -cc1 run-line from clang-tidy. This would allow arbitrary debugging over a single analyzer invocation.

[lebedev.ri]

In D46187#1088722, @NoQ wrote:

It seems that you're using debug checkers of the analyzer to gain some free tools for exploring the source code (such as displaying a call graph) for free, right?

Yes.
I was interested to dump the callgraph of DAGCombiner.cpp, and try to analyze if there is any sane way to split it up.
I think it would require a bit of changes to that callgraph dumper (writing LOC count for the functions that actually exist-as-written (or something) in the source code, grouping the functions in the main TU into a one group), but i did not get to that.

I believe we could also benefit from a method of extracting the analyzer's clang -cc1 run-line from clang-tidy. This would allow arbitrary debugging over a single analyzer invocation.

I'm not really following, sorry.

[alexfh]

In D46187#1088722, @NoQ wrote:

It seems that you're using debug checkers of the analyzer to gain some free tools for exploring the source code (such as displaying a call graph) for free, right?

I believe we could also benefit from a method of extracting the analyzer's clang -cc1 run-line from clang-tidy.

It should be possible now using clang-tidy -extra-arg=-v some/file.cpp (or clang-check -extra-arg=-v ...).

[NoQ]

In D46187#1089087, @lebedev.ri wrote:

I believe we could also benefit from a method of extracting the analyzer's clang -cc1 run-line from clang-tidy. This would allow arbitrary debugging over a single analyzer invocation.

I'm not really following, sorry.

In D46187#1091309, @alexfh wrote:

In D46187#1088722, @NoQ wrote:

I believe we could also benefit from a method of extracting the analyzer's clang -cc1 run-line from clang-tidy.

It should be possible now using clang-tidy -extra-arg=-v some/file.cpp (or clang-check -extra-arg=-v ...).

Nice!

So essentially @lebedev.ri could do clang-check -analyze -extra-arg=-v ../llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp, then copy the printed clang Invocation: and append -analyzer-checker debug.ViewCallGraph to it.

Or maybe even something as horrible as

clang-check -analyze -extra-arg=-Xclang -extra-arg=-analyzer-checker -extra-arg=-Xclang -extra-arg=debug.ViewCallGraph ../llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp

And it sounds like the roughly right level of verbosity for discriminating between a user-facing feature and a definitely-not-user-facing feature.

I don't mind having a separate flag specifically for enabling debug checkers, but when it comes to actual debugging of the analyzer, debug checkers are usually not sufficient. Playing with other flags and -analyzer-config options is very often necessary, so if i was to debug the analyzer from clang-tidy, most of the time i'd have preferred to do the -v trick.

[lebedev.ri]

Sad, but ok.

include/clang/StaticAnalyzer/Core/AnalyzerOptions.h

enum IPAKind {
   IPAK_DynamicDispatchBifurcate = 5
 };
 
 class AnalyzerOptions : public RefCountedBase<AnalyzerOptions> {
 public:
   using ConfigTable = llvm::StringMap<std::string>;
 
   static std::vector<StringRef>
-  getRegisteredCheckers(bool IncludeExperimental = false);
+  getRegisteredCheckers(bool IncludeExperimental = false,
+                        bool IncludeDebug = false);
 
   /// \brief Pair of checker name and enable/disable.
   std::vector<std::pair<std::string, bool>> CheckersControlList;
   
   /// \brief A key-value table of use-specified configuration values.
   ConfigTable Config;
   AnalysisStores AnalysisStoreOpt = RegionStoreModel;
   AnalysisConstraints AnalysisConstraintsOpt = RangeConstraintsModel;

lib/StaticAnalyzer/Core/AnalyzerOptions.cpp

 #include <utility>
 #include <vector>
 
 using namespace clang;
 using namespace ento;
 using namespace llvm;
 
 std::vector<StringRef>
-AnalyzerOptions::getRegisteredCheckers(bool IncludeExperimental /* = false */) {
+AnalyzerOptions::getRegisteredCheckers(bool IncludeExperimental /* = false */,
+                                       bool IncludeDebug /* = false */) {
   static const StringRef StaticAnalyzerChecks[] = {
 #define GET_CHECKERS
 #define CHECKER(FULLNAME, CLASS, DESCFILE, HELPTEXT, GROUPINDEX, HIDDEN)       \
   FULLNAME,
 #include "clang/StaticAnalyzer/Checkers/Checkers.inc"
 #undef CHECKER
 #undef GET_CHECKERS
   };
   std::vector<StringRef> Result;
   for (StringRef CheckName : StaticAnalyzerChecks) {
-    if (!CheckName.startswith("debug.") &&
-        (IncludeExperimental || !CheckName.startswith("alpha.")))
-      Result.push_back(CheckName);
+    if ((CheckName.startswith("alpha.") && !IncludeExperimental) ||
+        (CheckName.startswith("debug.") && !IncludeDebug))
+      continue;
   }
   return Result;
 }
 
 AnalyzerOptions::UserModeKind AnalyzerOptions::getUserMode() {
   if (UserMode == UMK_NotSet) {
     StringRef ModeStr =
         Config.insert(std::make_pair("mode", "deep")).first->second;

unittests/StaticAnalyzer/AnalyzerOptionsTest.cpp

 
 TEST(StaticAnalyzerOptions, getRegisteredCheckers) {
   auto IsDebugChecker = [](StringRef CheckerName) {
     return CheckerName.startswith("debug");
   };
   auto IsAlphaChecker = [](StringRef CheckerName) {
     return CheckerName.startswith("alpha");
   };
-  const auto &AllCheckers =
-      AnalyzerOptions::getRegisteredCheckers(/*IncludeExperimental=*/true);
-  EXPECT_FALSE(llvm::any_of(AllCheckers, IsDebugChecker));
+  const auto &AllCheckers = AnalyzerOptions::getRegisteredCheckers(
+      /*IncludeExperimental=*/true, /*IncludeDebug=*/true);
+  EXPECT_TRUE(llvm::any_of(AllCheckers, IsDebugChecker));
   EXPECT_TRUE(llvm::any_of(AllCheckers, IsAlphaChecker));
 
-  const auto &StableCheckers = AnalyzerOptions::getRegisteredCheckers();
+  const auto &AllNonDebugCheckers = AnalyzerOptions::getRegisteredCheckers(
+      /*IncludeExperimental=*/true, /*IncludeDebug=*/false);
+  EXPECT_FALSE(llvm::any_of(AllNonDebugCheckers, IsDebugChecker));
+  EXPECT_TRUE(llvm::any_of(AllNonDebugCheckers, IsAlphaChecker));
+
+  const auto &StableCheckers = AnalyzerOptions::getRegisteredCheckers(
+      /*IncludeExperimental=false,IncludeDebug=false*/);
   EXPECT_FALSE(llvm::any_of(StableCheckers, IsDebugChecker));
   EXPECT_FALSE(llvm::any_of(StableCheckers, IsAlphaChecker));
 }
 
 TEST(StaticAnalyzerOptions, SearchInParentPackageTests) {
   AnalyzerOptions Opts;
   Opts.Config["Outer.Inner.CheckerOne:Option"] = "true";
   Opts.Config["Outer.Inner:Option"] = "false";