[clang-query] add basic profiling on matching each ASTs (#114806)

We've found that basic profiling could help improving/optimizing when
developing clang-tidy checks.

This PR adds an extra command
```
set enable-profile (true|false)   Set whether to enable matcher profiling.
```
which enables profiling queries on each file.

Sample output:

```
$ cat test.cql
set enable-profile true
m binaryOperator(isExpansionInMainFile())

$ cat test.c
int test(int i, int j) {
  return i + j;
}

$ clang-query --track-memory -f test.cql test.c --

Match #1:

{{.*}}/test.c:2:10: note: "root" binds here
    2 |   return i + j;
      |          ^~~~~
1 match.
===-------------------------------------------------------------------------===
                         clang-query matcher profiling
===-------------------------------------------------------------------------===
  Total Execution Time: 0.0000 seconds (0.0000 wall clock)

   ---User Time---   --System Time--   --User+System--   ---Wall Time---  ---Mem---  --- Name ---
   0.0000 (100.0%)   0.0000 (100.0%)   0.0000 (100.0%)   0.0000 (100.0%)        224  {{.*}}/test.c
   0.0000 (100.0%)   0.0000 (100.0%)   0.0000 (100.0%)   0.0000 (100.0%)        224  Total
```

clang-tools-extra/clang-query/Query.cpp

@@ -44,7 +44,9 @@ bool HelpQuery::run(llvm::raw_ostream &OS, QuerySession &QS) const {
         "  set bind-root (true|false)        "
         "Set whether to bind the root matcher to \"root\".\n"
         "  set print-matcher (true|false)    "
-        "Set whether to print the current matcher,\n"
+        "Set whether to print the current matcher.\n"
+        "  set enable-profile (true|false)   "
+        "Set whether to enable matcher profiling.\n"
         "  set traversal <kind>              "
         "Set traversal kind of clang-query session. Available kinds are:\n"
         "    AsIs                            "
@@ -82,10 +84,24 @@ namespace {
 
 struct CollectBoundNodes : MatchFinder::MatchCallback {
   std::vector<BoundNodes> &Bindings;
-  CollectBoundNodes(std::vector<BoundNodes> &Bindings) : Bindings(Bindings) {}
+  StringRef Unit;
+  CollectBoundNodes(std::vector<BoundNodes> &Bindings, StringRef Unit)
+      : Bindings(Bindings), Unit(Unit) {}
   void run(const MatchFinder::MatchResult &Result) override {
     Bindings.push_back(Result.Nodes);
   }
+  StringRef getID() const override { return Unit; }
+};
+
+struct QueryProfiler {
+  llvm::StringMap<llvm::TimeRecord> Records;
+
+  ~QueryProfiler() {
+    llvm::TimerGroup TG("clang-query", "clang-query matcher profiling",
+                        Records);
+    TG.print(llvm::errs());
+    llvm::errs().flush();
+  }
 };
 
 } // namespace
@@ -93,8 +109,19 @@ struct CollectBoundNodes : MatchFinder::MatchCallback {
 bool MatchQuery::run(llvm::raw_ostream &OS, QuerySession &QS) const {
   unsigned MatchCount = 0;
 
+  std::optional<QueryProfiler> Profiler;
+  if (QS.EnableProfile)
+    Profiler.emplace();
+
   for (auto &AST : QS.ASTs) {
-    MatchFinder Finder;
+    ast_matchers::MatchFinder::MatchFinderOptions FinderOptions;
+    std::optional<llvm::StringMap<llvm::TimeRecord>> Records;
+    if (QS.EnableProfile) {
+      Records.emplace();
+      FinderOptions.CheckProfiling.emplace(*Records);
+    }
+
+    MatchFinder Finder(FinderOptions);
     std::vector<BoundNodes> Matches;
     DynTypedMatcher MaybeBoundMatcher = Matcher;
     if (QS.BindRoot) {
@@ -102,7 +129,8 @@ bool MatchQuery::run(llvm::raw_ostream &OS, QuerySession &QS) const {
       if (M)
         MaybeBoundMatcher = *M;
     }
-    CollectBoundNodes Collect(Matches);
+    StringRef OrigSrcName = AST->getOriginalSourceFileName();
+    CollectBoundNodes Collect(Matches, OrigSrcName);
     if (!Finder.addDynamicMatcher(MaybeBoundMatcher, &Collect)) {
       OS << "Not a valid top-level matcher.\n";
       return false;
@@ -111,6 +139,8 @@ bool MatchQuery::run(llvm::raw_ostream &OS, QuerySession &QS) const {
     ASTContext &Ctx = AST->getASTContext();
     Ctx.getParentMapContext().setTraversalKind(QS.TK);
     Finder.matchAST(Ctx);
+    if (QS.EnableProfile)
+      Profiler->Records[OrigSrcName] += (*Records)[OrigSrcName];
 
     if (QS.PrintMatcher) {
       SmallVector<StringRef, 4> Lines;

clang-tools-extra/clang-query/QueryParser.cpp

@@ -182,6 +182,7 @@ enum ParsedQueryVariable {
   PQV_Output,
   PQV_BindRoot,
   PQV_PrintMatcher,
+  PQV_EnableProfile,
   PQV_Traversal
 };
 
@@ -285,6 +286,7 @@ QueryRef QueryParser::doParse() {
             .Case("output", PQV_Output)
             .Case("bind-root", PQV_BindRoot)
             .Case("print-matcher", PQV_PrintMatcher)
+            .Case("enable-profile", PQV_EnableProfile)
             .Case("traversal", PQV_Traversal)
             .Default(PQV_Invalid);
     if (VarStr.empty())
@@ -303,6 +305,9 @@ QueryRef QueryParser::doParse() {
     case PQV_PrintMatcher:
       Q = parseSetBool(&QuerySession::PrintMatcher);
       break;
+    case PQV_EnableProfile:
+      Q = parseSetBool(&QuerySession::EnableProfile);
+      break;
     case PQV_Traversal:
       Q = parseSetTraversalKind(&QuerySession::TK);
       break;

clang-tools-extra/clang-query/QuerySession.h

@@ -26,7 +26,7 @@ public:
   QuerySession(llvm::ArrayRef<std::unique_ptr<ASTUnit>> ASTs)
       : ASTs(ASTs), PrintOutput(false), DiagOutput(true),
         DetailedASTOutput(false), BindRoot(true), PrintMatcher(false),
-        Terminate(false), TK(TK_AsIs) {}
+        EnableProfile(false), Terminate(false), TK(TK_AsIs) {}
 
   llvm::ArrayRef<std::unique_ptr<ASTUnit>> ASTs;
 
@@ -36,6 +36,7 @@ public:
 
   bool BindRoot;
   bool PrintMatcher;
+  bool EnableProfile;
   bool Terminate;
 
   TraversalKind TK;

clang-tools-extra/docs/ReleaseNotes.rst

@@ -98,7 +98,7 @@ Improvements to clang-doc
 Improvements to clang-query
 ---------------------------
 
-The improvements are...
+- Added `set enable-profile true/false` command for basic matcher profiling.
 
 Improvements to clang-tidy
 --------------------------