TrackConstraintBRVisitor and ConditionBRVisitor can emit similar
path notes for cases where a value may be assumed to be null, etc.
Instead of having redundant diagnostics, do a pass over the generated
PathDiagnostic pieces and remove notes from TrackConstraintBRVisitor
that are already covered by ConditionBRVisitor, whose notes tend
to be better.
Fixes <rdar://problem/12252783>
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@166728 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/StaticAnalyzer/Core/BugReporter.cpp b/lib/StaticAnalyzer/Core/BugReporter.cpp
index 6b94ac8..ed91988 100644
--- a/lib/StaticAnalyzer/Core/BugReporter.cpp
+++ b/lib/StaticAnalyzer/Core/BugReporter.cpp
@@ -118,6 +118,68 @@
// Diagnostic cleanup.
//===----------------------------------------------------------------------===//
+static PathDiagnosticEventPiece *
+eventsDescribeSameCondition(PathDiagnosticEventPiece *X,
+ PathDiagnosticEventPiece *Y) {
+ // Prefer diagnostics that come from ConditionBRVisitor over
+ // those that came from TrackConstraintBRVisitor.
+ const void *tagPreferred = ConditionBRVisitor::getTag();
+ const void *tagLesser = TrackConstraintBRVisitor::getTag();
+
+ if (X->getLocation() != Y->getLocation())
+ return 0;
+
+ if (X->getTag() == tagPreferred && Y->getTag() == tagLesser)
+ return X;
+
+ if (Y->getTag() == tagPreferred && X->getTag() == tagLesser)
+ return Y;
+
+ return 0;
+}
+
+static void RemoveRedundantMsgs(PathPieces &path) {
+ unsigned N = path.size();
+ if (N < 2)
+ return;
+ for (unsigned i = 0; i < N; ++i) {
+ IntrusiveRefCntPtr<PathDiagnosticPiece> piece(path.front());
+ path.pop_front();
+
+ switch (piece->getKind()) {
+ case clang::ento::PathDiagnosticPiece::Call:
+ RemoveRedundantMsgs(cast<PathDiagnosticCallPiece>(piece)->path);
+ break;
+ case clang::ento::PathDiagnosticPiece::Macro:
+ RemoveRedundantMsgs(cast<PathDiagnosticMacroPiece>(piece)->subPieces);
+ break;
+ case clang::ento::PathDiagnosticPiece::ControlFlow:
+ break;
+ case clang::ento::PathDiagnosticPiece::Event: {
+ if (i == N-1)
+ break;
+
+ if (PathDiagnosticEventPiece *nextEvent =
+ dyn_cast<PathDiagnosticEventPiece>(path.front().getPtr())) {
+ PathDiagnosticEventPiece *event =
+ cast<PathDiagnosticEventPiece>(piece);
+ // Check to see if we should keep one of the two pieces. If we
+ // come up with a preference, record which piece to keep, and consume
+ // another piece from the path.
+ if (PathDiagnosticEventPiece *pieceToKeep =
+ eventsDescribeSameCondition(event, nextEvent)) {
+ piece = pieceToKeep;
+ path.pop_front();
+ ++i;
+ }
+ }
+ break;
+ }
+ }
+ path.push_back(piece);
+ }
+}
+
/// Recursively scan through a path and prune out calls and macros pieces
/// that aren't needed. Return true if afterwards the path contains
/// "interesting stuff" which means it should be pruned from the parent path.
@@ -2016,10 +2078,16 @@
} while(finalReportConfigToken != originalReportConfigToken);
// Finally, prune the diagnostic path of uninteresting stuff.
- if (!PD.path.empty() && R->shouldPrunePath()) {
- bool hasSomethingInteresting = RemoveUneededCalls(PD.getMutablePieces(), R);
- assert(hasSomethingInteresting);
- (void) hasSomethingInteresting;
+ if (!PD.path.empty()) {
+ // Remove messages that are basically the same.
+ RemoveRedundantMsgs(PD.getMutablePieces());
+
+ if (R->shouldPrunePath()) {
+ bool hasSomethingInteresting = RemoveUneededCalls(PD.getMutablePieces(),
+ R);
+ assert(hasSomethingInteresting);
+ (void) hasSomethingInteresting;
+ }
}
return true;