Add comments for RemoveRedundantMsgs, rename it to removeRedundantMsgs() per Jordan's feedback.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@166778 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/StaticAnalyzer/Core/BugReporter.cpp b/lib/StaticAnalyzer/Core/BugReporter.cpp
index ed91988..2bf701b 100644
--- a/lib/StaticAnalyzer/Core/BugReporter.cpp
+++ b/lib/StaticAnalyzer/Core/BugReporter.cpp
@@ -138,20 +138,29 @@
return 0;
}
-static void RemoveRedundantMsgs(PathPieces &path) {
+/// An optimization pass over PathPieces that removes redundant diagnostics
+/// generated by both ConditionBRVisitor and TrackConstraintBRVisitor. Both
+/// BugReporterVisitors use different methods to generate diagnostics, with
+/// one capable of emitting diagnostics in some cases but not in others. This
+/// can lead to redundant diagnostic pieces at the same point in a path.
+static void removeRedundantMsgs(PathPieces &path) {
unsigned N = path.size();
if (N < 2)
return;
+ // NOTE: this loop intentionally is not using an iterator. Instead, we
+ // are streaming the path and modifying it in place. This is done by
+ // grabbing the front, processing it, and if we decide to keep it append
+ // it to the end of the path. The entire path is processed in this way.
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);
+ removeRedundantMsgs(cast<PathDiagnosticCallPiece>(piece)->path);
break;
case clang::ento::PathDiagnosticPiece::Macro:
- RemoveRedundantMsgs(cast<PathDiagnosticMacroPiece>(piece)->subPieces);
+ removeRedundantMsgs(cast<PathDiagnosticMacroPiece>(piece)->subPieces);
break;
case clang::ento::PathDiagnosticPiece::ControlFlow:
break;
@@ -2080,7 +2089,7 @@
// Finally, prune the diagnostic path of uninteresting stuff.
if (!PD.path.empty()) {
// Remove messages that are basically the same.
- RemoveRedundantMsgs(PD.getMutablePieces());
+ removeRedundantMsgs(PD.getMutablePieces());
if (R->shouldPrunePath()) {
bool hasSomethingInteresting = RemoveUneededCalls(PD.getMutablePieces(),