[clang][analyzer] Make per-entry-point metric rows uniquely identifiable

Also remove the gratuitous spaces after "," that break strict CSV
compliance.

As the debug function name does not uniquely identify an entry point,
add the main-TU name and the USR values for each entry point snapshot to
reduce the likelihood of collisions between declarations across large
projects.

While adding a filename to each row increases the file size
substantially, the difference in size for the compressed is acceptable.

I evaluated it on our set of 200+ open source C and C++ projects with 3M
entry points, and got the following results when adding these two
columns:
- Raw CSV file increased from 530MB to 1.1GB
- Compressed file (XZ) increased from 54 MB to 78 MB

--

CPP-7098

---------

Co-authored-by: Balazs Benics <[email protected]>

Author: necto

clang/include/clang/StaticAnalyzer/Core/PathSensitive/EntryPointStats.h

@@ -25,7 +25,7 @@ class EntryPointStat {
 public:
   llvm::StringLiteral name() const { return Name; }
 
-  static void lockRegistry();
+  static void lockRegistry(llvm::StringRef CPPFileName);
 
   static void takeSnapshot(const Decl *EntryPoint);
   static void dumpStatsAsCSV(llvm::raw_ostream &OS);

clang/lib/StaticAnalyzer/Core/EntryPointStats.cpp

@@ -9,7 +9,9 @@
 #include "clang/StaticAnalyzer/Core/PathSensitive/EntryPointStats.h"
 #include "clang/AST/DeclBase.h"
 #include "clang/Analysis/AnalysisDeclContext.h"
+#include "clang/Index/USRGeneration.h"
 #include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/Support/FileSystem.h"
@@ -38,6 +40,7 @@ struct Registry {
   };
 
   std::vector<Snapshot> Snapshots;
+  std::string EscapedCPPFileName;
 };
 } // namespace
 
@@ -69,7 +72,7 @@ static void checkStatName(const EntryPointStat *M) {
   }
 }
 
-void EntryPointStat::lockRegistry() {
+void EntryPointStat::lockRegistry(llvm::StringRef CPPFileName) {
   auto CmpByNames = [](const EntryPointStat *L, const EntryPointStat *R) {
     return L->name() < R->name();
   };
@@ -78,6 +81,8 @@ void EntryPointStat::lockRegistry() {
   enumerateStatVectors(
       [](const auto &Stats) { llvm::for_each(Stats, checkStatName); });
   StatsRegistry->IsLocked = true;
+  llvm::raw_string_ostream OS(StatsRegistry->EscapedCPPFileName);
+  llvm::printEscapedString(CPPFileName, OS);
 }
 
 [[maybe_unused]] static bool isRegistered(llvm::StringLiteral Name) {
@@ -144,15 +149,27 @@ static std::vector<llvm::StringLiteral> getStatNames() {
   return Ret;
 }
 
+static std::string getUSR(const Decl *D) {
+  llvm::SmallVector<char> Buf;
+  if (index::generateUSRForDecl(D, Buf)) {
+    assert(false && "This should never fail");
+    return AnalysisDeclContext::getFunctionName(D);
+  }
+  return llvm::toStringRef(Buf).str();
+}
+
 void Registry::Snapshot::dumpAsCSV(llvm::raw_ostream &OS) const {
   OS << '"';
+  llvm::printEscapedString(getUSR(EntryPoint), OS);
+  OS << "\",\"";
+  OS << StatsRegistry->EscapedCPPFileName << "\",\"";
   llvm::printEscapedString(
       clang::AnalysisDeclContext::getFunctionName(EntryPoint), OS);
-  OS << "\", ";
+  OS << "\",";
   auto PrintAsBool = [&OS](bool B) { OS << (B ? "true" : "false"); };
-  llvm::interleaveComma(BoolStatValues, OS, PrintAsBool);
-  OS << ((BoolStatValues.empty() || UnsignedStatValues.empty()) ? "" : ", ");
-  llvm::interleaveComma(UnsignedStatValues, OS);
+  llvm::interleave(BoolStatValues, OS, PrintAsBool, ",");
+  OS << ((BoolStatValues.empty() || UnsignedStatValues.empty()) ? "" : ",");
+  llvm::interleave(UnsignedStatValues, OS, [&OS](unsigned U) { OS << U; }, ",");
 }
 
 static std::vector<bool> consumeBoolStats() {
@@ -181,8 +198,8 @@ void EntryPointStat::dumpStatsAsCSV(llvm::StringRef FileName) {
 }
 
 void EntryPointStat::dumpStatsAsCSV(llvm::raw_ostream &OS) {
-  OS << "EntryPoint, ";
-  llvm::interleaveComma(getStatNames(), OS);
+  OS << "USR,File,DebugName,";
+  llvm::interleave(getStatNames(), OS, [&OS](const auto &a) { OS << a; }, ",");
   OS << "\n";
 
   std::vector<std::string> Rows;

clang/lib/StaticAnalyzer/Frontend/AnalysisConsumer.cpp

@@ -65,6 +65,15 @@ STAT_MAX(MaxCFGSize, "The maximum number of basic blocks in a function.");
 
 namespace {
 
+StringRef getMainFileName(const CompilerInvocation &Invocation) {
+  if (!Invocation.getFrontendOpts().Inputs.empty()) {
+    const FrontendInputFile &Input = Invocation.getFrontendOpts().Inputs[0];
+    return Input.isFile() ? Input.getFile()
+                          : Input.getBuffer().getBufferIdentifier();
+  }
+  return "<no input>";
+}
+
 class AnalysisConsumer : public AnalysisASTConsumer,
                          public DynamicRecursiveASTVisitor {
   enum {
@@ -125,7 +134,8 @@ class AnalysisConsumer : public AnalysisASTConsumer,
         PP(CI.getPreprocessor()), OutDir(outdir), Opts(opts), Plugins(plugins),
         Injector(std::move(injector)), CTU(CI),
         MacroExpansions(CI.getLangOpts()) {
-    EntryPointStat::lockRegistry();
+
+    EntryPointStat::lockRegistry(getMainFileName(CI.getInvocation()));
     DigestAnalyzerOptions();
 
     if (Opts.AnalyzerDisplayProgress || Opts.PrintStats ||

clang/test/Analysis/analyzer-stats/entry-point-stats.cpp

@@ -5,7 +5,9 @@
 // RUN: %csv2json "%t.csv" | FileCheck --check-prefix=CHECK %s
 //
 // CHECK:      {
-// CHECK-NEXT:   "fib(unsigned int)": {
+// CHECK-NEXT:   "c:@F@fib#i#": {
+// CHECK-NEXT:     "File": "{{.*}}entry-point-stats.cpp",
+// CHECK-NEXT:     "DebugName": "fib(unsigned int)",
 // CHECK-NEXT:     "NumBlocks": "{{[0-9]+}}",
 // CHECK-NEXT:     "NumBlocksUnreachable": "{{[0-9]+}}",
 // CHECK-NEXT:     "NumCTUSteps": "{{[0-9]+}}",
@@ -40,7 +42,9 @@
 // CHECK-NEXT:     "MaxValidBugClassSize": "{{[0-9]+}}",
 // CHECK-NEXT:     "PathRunningTime": "{{[0-9]+}}"
 // CHECK-NEXT:   },
-// CHECK-NEXT:   "main(int, char **)": {
+// CHECK-NEXT:   "c:@F@main#I#**C#": {
+// CHECK-NEXT:     "File": "{{.*}}entry-point-stats.cpp",
+// CHECK-NEXT:     "DebugName": "main(int, char **)",
 // CHECK-NEXT:     "NumBlocks": "{{[0-9]+}}",
 // CHECK-NEXT:     "NumBlocksUnreachable": "{{[0-9]+}}",
 // CHECK-NEXT:     "NumCTUSteps": "{{[0-9]+}}",