[analyzer] Mention whether an event is about a condition in a bug report part 1

Can't add much more to the title! This is part 1, the case where the collapse
point isn't in the condition point is the responsibility of ConditionBRVisitor,
which I'm addressing in part 2.

Differential Revision: https://reviews.llvm.org/D65575

llvm-svn: 369574

1 files changed, 15 insertions, 3 deletions

diff --git a/clang/lib/StaticAnalyzer/Core/BugReporterVisitors.cpp b/clang/lib/StaticAnalyzer/Core/BugReporterVisitors.cpp
index f864098a227..3dc50627b6f 100644
--- a/clang/lib/StaticAnalyzer/Core/BugReporterVisitors.cpp
+++ b/clang/lib/StaticAnalyzer/Core/BugReporterVisitors.cpp
@@ -298,6 +298,7 @@ class NoStoreFuncVisitor final : public BugReporterVisitor {
   MemRegionManager &MmrMgr;
   const SourceManager &SM;
   const PrintingPolicy &PP;
+  bugreporter::TrackingKind TKind;
 
   /// Recursion limit for dereferencing fields when looking for the
   /// region of interest.
@@ -318,10 +319,10 @@ class NoStoreFuncVisitor final : public BugReporterVisitor {
   using RegionVector = SmallVector<const MemRegion *, 5>;
 
 public:
-  NoStoreFuncVisitor(const SubRegion *R)
+  NoStoreFuncVisitor(const SubRegion *R, bugreporter::TrackingKind TKind)
       : RegionOfInterest(R), MmrMgr(*R->getMemRegionManager()),
         SM(MmrMgr.getContext().getSourceManager()),
-        PP(MmrMgr.getContext().getPrintingPolicy()) {}
+        PP(MmrMgr.getContext().getPrintingPolicy()), TKind(TKind) {}
 
   void Profile(llvm::FoldingSetNodeID &ID) const override {
     static int Tag = 0;
@@ -612,6 +613,9 @@ void NoStoreFuncVisitor::findModifyingFrames(const ExplodedNode *N) {
   } while (N);
 }
 
+static llvm::StringLiteral WillBeUsedForACondition =
+    ", which participates in a condition later";
+
 PathDiagnosticPieceRef NoStoreFuncVisitor::maybeEmitNote(
     BugReport &R, const CallEvent &Call, const ExplodedNode *N,
     const RegionVector &FieldChain, const MemRegion *MatchedRegion,
@@ -658,6 +662,8 @@ PathDiagnosticPieceRef NoStoreFuncVisitor::maybeEmitNote(
     return nullptr;
 
   os << "'";
+  if (TKind == bugreporter::TrackingKind::Condition)
+    os << WillBeUsedForACondition;
   return std::make_shared<PathDiagnosticEventPiece>(L, os.str());
 }
 
@@ -1068,6 +1074,9 @@ public:
     if (!L.isValid() || !L.asLocation().isValid())
       return nullptr;
 
+    if (TKind == bugreporter::TrackingKind::Condition)
+      Out << WillBeUsedForACondition;
+
     auto EventPiece = std::make_shared<PathDiagnosticEventPiece>(L, Out.str());
 
     // If we determined that the note is meaningless, make it prunable, and
@@ -1450,6 +1459,9 @@ FindLastStoreBRVisitor::VisitNode(const ExplodedNode *Succ,
   if (os.str().empty())
     showBRDefaultDiagnostics(os, R, V);
 
+  if (TKind == bugreporter::TrackingKind::Condition)
+    os << WillBeUsedForACondition;
+
   // Construct a new PathDiagnosticPiece.
   ProgramPoint P = StoreSite->getLocation();
   PathDiagnosticLocation L;
@@ -1933,7 +1945,7 @@ bool bugreporter::trackExpressionValue(const ExplodedNode *InputNode,
       // Mark both the variable region and its contents as interesting.
       SVal V = LVState->getRawSVal(loc::MemRegionVal(R));
       report.addVisitor(
-          std::make_unique<NoStoreFuncVisitor>(cast<SubRegion>(R)));
+          std::make_unique<NoStoreFuncVisitor>(cast<SubRegion>(R), TKind));
 
       MacroNullReturnSuppressionVisitor::addMacroVisitorIfNecessary(
           LVNode, R, EnableNullFPSuppression, report, V);