[clang-tidy] Profile is a per-AST (per-TU) data.

Summary:
As discussed in D45931, currently, profiling output of clang-tidy is somewhat not great.
It outputs one profile at the end of the execution, and that profile contains the data
from the last TU that was processed. So if the tool run on multiple TU's, the data is
not accumulated, it is simply discarded.

It would be nice to improve this.

This differential is the first step - make this profiling info per-TU,
and output it after the tool has finished processing each TU.
In particular, when `ClangTidyASTConsumer` destructor runs.

Next step will be to add a CSV (JSON?) printer to store said profiles under user-specified directory prefix.

Reviewers: alexfh, sbenza

Reviewed By: alexfh

Subscribers: Eugene.Zelenko, mgorny, xazax.hun, mgrang, klimek, cfe-commits

Tags: #clang-tools-extra

Differential Revision: https://reviews.llvm.org/D46504

llvm-svn: 331763
GitOrigin-RevId: 12152511518ef370a24923539a3ac792e387789f
diff --git a/clang-tidy/CMakeLists.txt b/clang-tidy/CMakeLists.txt
index 6738c31..a872469 100644
--- a/clang-tidy/CMakeLists.txt
+++ b/clang-tidy/CMakeLists.txt
@@ -7,6 +7,7 @@
   ClangTidyModule.cpp
   ClangTidyDiagnosticConsumer.cpp
   ClangTidyOptions.cpp
+  ClangTidyProfiling.cpp
 
   DEPENDS
   ClangSACheckers
diff --git a/clang-tidy/ClangTidy.cpp b/clang-tidy/ClangTidy.cpp
index 59ee604..1493fbb 100644
--- a/clang-tidy/ClangTidy.cpp
+++ b/clang-tidy/ClangTidy.cpp
@@ -18,6 +18,7 @@
 #include "ClangTidy.h"
 #include "ClangTidyDiagnosticConsumer.h"
 #include "ClangTidyModuleRegistry.h"
+#include "ClangTidyProfiling.h"
 #include "clang/AST/ASTConsumer.h"
 #include "clang/AST/ASTContext.h"
 #include "clang/AST/Decl.h"
@@ -267,12 +268,17 @@
 class ClangTidyASTConsumer : public MultiplexConsumer {
 public:
   ClangTidyASTConsumer(std::vector<std::unique_ptr<ASTConsumer>> Consumers,
+                       std::unique_ptr<ClangTidyProfiling> Profiling,
                        std::unique_ptr<ast_matchers::MatchFinder> Finder,
                        std::vector<std::unique_ptr<ClangTidyCheck>> Checks)
-      : MultiplexConsumer(std::move(Consumers)), Finder(std::move(Finder)),
+      : MultiplexConsumer(std::move(Consumers)),
+        Profiling(std::move(Profiling)), Finder(std::move(Finder)),
         Checks(std::move(Checks)) {}
 
 private:
+  // Destructor order matters! Profiling must be destructed last.
+  // Or at least after Finder.
+  std::unique_ptr<ClangTidyProfiling> Profiling;
   std::unique_ptr<ast_matchers::MatchFinder> Finder;
   std::vector<std::unique_ptr<ClangTidyCheck>> Checks;
 };
@@ -353,8 +359,12 @@
   CheckFactories->createChecks(&Context, Checks);
 
   ast_matchers::MatchFinder::MatchFinderOptions FinderOptions;
-  if (auto *P = Context.getCheckProfileData())
-    FinderOptions.CheckProfiling.emplace(P->Records);
+
+  std::unique_ptr<ClangTidyProfiling> Profiling;
+  if (Context.getEnableProfiling()) {
+    Profiling = llvm::make_unique<ClangTidyProfiling>();
+    FinderOptions.CheckProfiling.emplace(Profiling->Records);
+  }
 
   std::unique_ptr<ast_matchers::MatchFinder> Finder(
       new ast_matchers::MatchFinder(std::move(FinderOptions)));
@@ -383,7 +393,8 @@
     Consumers.push_back(std::move(AnalysisConsumer));
   }
   return llvm::make_unique<ClangTidyASTConsumer>(
-      std::move(Consumers), std::move(Finder), std::move(Checks));
+      std::move(Consumers), std::move(Profiling), std::move(Finder),
+      std::move(Checks));
 }
 
 std::vector<std::string> ClangTidyASTConsumerFactory::getCheckNames() {
@@ -472,7 +483,7 @@
                   const CompilationDatabase &Compilations,
                   ArrayRef<std::string> InputFiles,
                   llvm::IntrusiveRefCntPtr<vfs::FileSystem> BaseFS,
-                  ProfileData *Profile) {
+                  bool EnableCheckProfile) {
   ClangTool Tool(Compilations, InputFiles,
                  std::make_shared<PCHContainerOperations>(), BaseFS);
 
@@ -512,8 +523,7 @@
 
   Tool.appendArgumentsAdjuster(PerFileExtraArgumentsInserter);
   Tool.appendArgumentsAdjuster(PluginArgumentsRemover);
-  if (Profile)
-    Context.setCheckProfileData(Profile);
+  Context.setEnableProfiling(EnableCheckProfile);
 
   ClangTidyDiagnosticConsumer DiagConsumer(Context);
 
diff --git a/clang-tidy/ClangTidy.h b/clang-tidy/ClangTidy.h
index 7c9ef76..c68f6ed 100644
--- a/clang-tidy/ClangTidy.h
+++ b/clang-tidy/ClangTidy.h
@@ -228,7 +228,7 @@
                   const tooling::CompilationDatabase &Compilations,
                   ArrayRef<std::string> InputFiles,
                   llvm::IntrusiveRefCntPtr<vfs::FileSystem> BaseFS,
-                  ProfileData *Profile = nullptr);
+                  bool EnableCheckProfile = false);
 
 // FIXME: This interface will need to be significantly extended to be useful.
 // FIXME: Implement confidence levels for displaying/fixing errors.
diff --git a/clang-tidy/ClangTidyDiagnosticConsumer.cpp b/clang-tidy/ClangTidyDiagnosticConsumer.cpp
index d3c1754..dd4f658 100644
--- a/clang-tidy/ClangTidyDiagnosticConsumer.cpp
+++ b/clang-tidy/ClangTidyDiagnosticConsumer.cpp
@@ -179,7 +179,7 @@
 ClangTidyContext::ClangTidyContext(
     std::unique_ptr<ClangTidyOptionsProvider> OptionsProvider)
     : DiagEngine(nullptr), OptionsProvider(std::move(OptionsProvider)),
-      Profile(nullptr) {
+      Profile(false) {
   // Before the first translation unit we can get errors related to command-line
   // parsing, use empty string for the file name in this case.
   setCurrentFile("");
@@ -233,7 +233,7 @@
       OptionsProvider->getOptions(File));
 }
 
-void ClangTidyContext::setCheckProfileData(ProfileData *P) { Profile = P; }
+void ClangTidyContext::setEnableProfiling(bool P) { Profile = P; }
 
 bool ClangTidyContext::isCheckEnabled(StringRef CheckName) const {
   assert(CheckFilter != nullptr);
diff --git a/clang-tidy/ClangTidyDiagnosticConsumer.h b/clang-tidy/ClangTidyDiagnosticConsumer.h
index b484794..60e5040 100644
--- a/clang-tidy/ClangTidyDiagnosticConsumer.h
+++ b/clang-tidy/ClangTidyDiagnosticConsumer.h
@@ -87,11 +87,6 @@
   }
 };
 
-/// \brief Container for clang-tidy profiling data.
-struct ProfileData {
-  llvm::StringMap<llvm::TimeRecord> Records;
-};
-
 /// \brief Every \c ClangTidyCheck reports errors through a \c DiagnosticsEngine
 /// provided by this context.
 ///
@@ -169,12 +164,9 @@
   /// \brief Clears collected errors.
   void clearErrors() { Errors.clear(); }
 
-  /// \brief Set the output struct for profile data.
-  ///
-  /// Setting a non-null pointer here will enable profile collection in
-  /// clang-tidy.
-  void setCheckProfileData(ProfileData *Profile);
-  ProfileData *getCheckProfileData() const { return Profile; }
+  /// \brief Control profile collection in clang-tidy.
+  void setEnableProfiling(bool Profile);
+  bool getEnableProfiling() const { return Profile; }
 
   /// \brief Should be called when starting to process new translation unit.
   void setCurrentBuildDirectory(StringRef BuildDirectory) {
@@ -216,7 +208,7 @@
 
   llvm::DenseMap<unsigned, std::string> CheckNamesByDiagnosticID;
 
-  ProfileData *Profile;
+  bool Profile;
 };
 
 /// \brief A diagnostic consumer that turns each \c Diagnostic into a
diff --git a/clang-tidy/ClangTidyProfiling.cpp b/clang-tidy/ClangTidyProfiling.cpp
new file mode 100644
index 0000000..d332942
--- /dev/null
+++ b/clang-tidy/ClangTidyProfiling.cpp
@@ -0,0 +1,65 @@
+//===--- ClangTidyProfiling.cpp - clang-tidy --------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "ClangTidyProfiling.h"
+#include "llvm/ADT/STLExtras.h"
+
+#define DEBUG_TYPE "clang-tidy-profiling"
+
+namespace clang {
+namespace tidy {
+
+void ClangTidyProfiling::preprocess() {
+  // Convert from a insertion-friendly map to sort-friendly vector.
+  Timers.clear();
+  Timers.reserve(Records.size());
+  for (const auto &P : Records) {
+    Timers.emplace_back(P.getValue(), P.getKey());
+    Total += P.getValue();
+  }
+  assert(Timers.size() == Records.size() && "Size mismatch after processing");
+
+  // We want the measurements to be sorted by decreasing time spent.
+  llvm::sort(Timers.begin(), Timers.end());
+}
+
+void ClangTidyProfiling::printProfileData(llvm::raw_ostream &OS) const {
+  std::string Line = "===" + std::string(73, '-') + "===\n";
+  OS << Line;
+
+  if (Total.getUserTime())
+    OS << "   ---User Time---";
+  if (Total.getSystemTime())
+    OS << "   --System Time--";
+  if (Total.getProcessTime())
+    OS << "   --User+System--";
+  OS << "   ---Wall Time---";
+  if (Total.getMemUsed())
+    OS << "  ---Mem---";
+  OS << "  --- Name ---\n";
+
+  // Loop through all of the timing data, printing it out.
+  for (auto I = Timers.rbegin(), E = Timers.rend(); I != E; ++I) {
+    I->first.print(Total, OS);
+    OS << I->second << '\n';
+  }
+
+  Total.print(Total, OS);
+  OS << "Total\n";
+  OS << Line << "\n";
+  OS.flush();
+}
+
+ClangTidyProfiling::~ClangTidyProfiling() {
+  preprocess();
+  printProfileData(llvm::errs());
+}
+
+} // namespace tidy
+} // namespace clang
diff --git a/clang-tidy/ClangTidyProfiling.h b/clang-tidy/ClangTidyProfiling.h
new file mode 100644
index 0000000..002a148
--- /dev/null
+++ b/clang-tidy/ClangTidyProfiling.h
@@ -0,0 +1,41 @@
+//===--- ClangTidyProfiling.h - clang-tidy ----------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CLANGTIDYPROFILING_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CLANGTIDYPROFILING_H
+
+#include "llvm/ADT/StringMap.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/Support/Timer.h"
+#include "llvm/Support/raw_ostream.h"
+#include <utility>
+#include <vector>
+
+namespace clang {
+namespace tidy {
+
+class ClangTidyProfiling {
+  // Time is first to allow for sorting by it.
+  std::vector<std::pair<llvm::TimeRecord, llvm::StringRef>> Timers;
+  llvm::TimeRecord Total;
+
+  void preprocess();
+
+  void printProfileData(llvm::raw_ostream &OS) const;
+
+public:
+  llvm::StringMap<llvm::TimeRecord> Records;
+
+  ~ClangTidyProfiling();
+};
+
+} // end namespace tidy
+} // end namespace clang
+
+#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CLANGTIDYPROFILING_H
diff --git a/clang-tidy/tool/ClangTidyMain.cpp b/clang-tidy/tool/ClangTidyMain.cpp
index 12c0e47..07accbb 100644
--- a/clang-tidy/tool/ClangTidyMain.cpp
+++ b/clang-tidy/tool/ClangTidyMain.cpp
@@ -236,45 +236,6 @@
   }
 }
 
-static void printProfileData(const ProfileData &Profile,
-                             llvm::raw_ostream &OS) {
-  // Time is first to allow for sorting by it.
-  std::vector<std::pair<llvm::TimeRecord, StringRef>> Timers;
-  TimeRecord Total;
-
-  for (const auto &P : Profile.Records) {
-    Timers.emplace_back(P.getValue(), P.getKey());
-    Total += P.getValue();
-  }
-
-  std::sort(Timers.begin(), Timers.end());
-
-  std::string Line = "===" + std::string(73, '-') + "===\n";
-  OS << Line;
-
-  if (Total.getUserTime())
-    OS << "   ---User Time---";
-  if (Total.getSystemTime())
-    OS << "   --System Time--";
-  if (Total.getProcessTime())
-    OS << "   --User+System--";
-  OS << "   ---Wall Time---";
-  if (Total.getMemUsed())
-    OS << "  ---Mem---";
-  OS << "  --- Name ---\n";
-
-  // Loop through all of the timing data, printing it out.
-  for (auto I = Timers.rbegin(), E = Timers.rend(); I != E; ++I) {
-    I->first.print(Total, OS);
-    OS << I->second << '\n';
-  }
-
-  Total.print(Total, OS);
-  OS << "Total\n";
-  OS << Line << "\n";
-  OS.flush();
-}
-
 static std::unique_ptr<ClangTidyOptionsProvider> createOptionsProvider(
    llvm::IntrusiveRefCntPtr<vfs::FileSystem> FS) {
   ClangTidyGlobalOptions GlobalOptions;
@@ -424,7 +385,6 @@
     llvm::cl::PrintHelpMessage(/*Hidden=*/false, /*Categorized=*/true);
     return 1;
   }
-  ProfileData Profile;
 
   llvm::InitializeAllTargetInfos();
   llvm::InitializeAllTargetMCs();
@@ -432,7 +392,7 @@
 
   ClangTidyContext Context(std::move(OwningOptionsProvider));
   runClangTidy(Context, OptionsParser.getCompilations(), PathList, BaseFS,
-               EnableCheckProfile ? &Profile : nullptr);
+               EnableCheckProfile);
   ArrayRef<ClangTidyError> Errors = Context.getErrors();
   bool FoundErrors = llvm::find_if(Errors, [](const ClangTidyError &E) {
                        return E.DiagLevel == ClangTidyError::Error;
@@ -464,9 +424,6 @@
              "Fixes have NOT been applied.\n\n";
   }
 
-  if (EnableCheckProfile)
-    printProfileData(Profile, llvm::errs());
-
   if (WErrorCount) {
     if (!Quiet) {
       StringRef Plural = WErrorCount == 1 ? "" : "s";
diff --git a/test/clang-tidy/clang-tidy-enable-check-profile-one-tu.cpp b/test/clang-tidy/clang-tidy-enable-check-profile-one-tu.cpp
new file mode 100644
index 0000000..523b6eb
--- /dev/null
+++ b/test/clang-tidy/clang-tidy-enable-check-profile-one-tu.cpp
@@ -0,0 +1,18 @@
+// RUN: clang-tidy -enable-check-profile -checks='-*,readability-function-size' %s 2>&1 | FileCheck --match-full-lines -implicit-check-not='{{warning:|error:}}' %s
+
+// CHECK: ===-------------------------------------------------------------------------===
+// CHECK-NEXT: {{.*}}  --- Name ---
+// CHECK-NEXT: {{.*}}  readability-function-size
+// CHECK-NEXT: {{.*}}  Total
+// CHECK-NEXT: ===-------------------------------------------------------------------------===
+
+// CHECK-NOT: ===-------------------------------------------------------------------------===
+// CHECK-NOT: {{.*}}  --- Name ---
+// CHECK-NOT: {{.*}}  readability-function-size
+// CHECK-NOT: {{.*}}  Total
+// CHECK-NOT: ===-------------------------------------------------------------------------===
+
+class A {
+  A() {}
+  ~A() {}
+};
diff --git a/test/clang-tidy/clang-tidy-enable-check-profile-two-tu.cpp b/test/clang-tidy/clang-tidy-enable-check-profile-two-tu.cpp
new file mode 100644
index 0000000..9777dc9
--- /dev/null
+++ b/test/clang-tidy/clang-tidy-enable-check-profile-two-tu.cpp
@@ -0,0 +1,24 @@
+// RUN: clang-tidy -enable-check-profile -checks='-*,readability-function-size' %s %s 2>&1 | FileCheck --match-full-lines -implicit-check-not='{{warning:|error:}}' %s
+
+// CHECK: ===-------------------------------------------------------------------------===
+// CHECK-NEXT: {{.*}}  --- Name ---
+// CHECK-NEXT: {{.*}}  readability-function-size
+// CHECK-NEXT: {{.*}}  Total
+// CHECK-NEXT: ===-------------------------------------------------------------------------===
+
+// CHECK: ===-------------------------------------------------------------------------===
+// CHECK-NEXT: {{.*}}  --- Name ---
+// CHECK-NEXT: {{.*}}  readability-function-size
+// CHECK-NEXT: {{.*}}  Total
+// CHECK-NEXT: ===-------------------------------------------------------------------------===
+
+// CHECK-NOT: ===-------------------------------------------------------------------------===
+// CHECK-NOT: {{.*}}  --- Name ---
+// CHECK-NOT: {{.*}}  readability-function-size
+// CHECK-NOT: {{.*}}  Total
+// CHECK-NOT: ===-------------------------------------------------------------------------===
+
+class A {
+  A() {}
+  ~A() {}
+};