[analyzer] Implement basic path diagnostic pruning based on "interesting" symbols and regions.

Essentially, a bug centers around a story for various symbols and regions.  We should only include
the path diagnostic events that relate to those symbols and regions.

The pruning is done by associating a set of interesting symbols and regions with a BugReporter, which
can be modified at BugReport creation or by BugReporterVisitors.

This patch reduces the diagnostics emitted in several of our test cases.  I've vetted these as
having desired behavior.  The only regression is a missing null check diagnostic for the return
value of realloc() in test/Analysis/malloc-plist.c.  This will require some investigation to fix,
and I have added a FIXME to the test case.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@152361 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 12 insertions, 0 deletions

diff --git a/lib/StaticAnalyzer/Checkers/MacOSKeychainAPIChecker.cpp b/lib/StaticAnalyzer/Checkers/MacOSKeychainAPIChecker.cpp
index b96bc66b6f..1b8dd6874c 100644
--- a/lib/StaticAnalyzer/Checkers/MacOSKeychainAPIChecker.cpp
+++ b/lib/StaticAnalyzer/Checkers/MacOSKeychainAPIChecker.cpp
@@ -121,6 +121,12 @@ private:
                                    SValBuilder &Builder) const {
     return definitelyReturnedError(RetSym, State, Builder, true);
   }
+                                                 
+  /// Mark an AllocationPair interesting for diagnostic reporting.
+  void markInteresting(BugReport *R, const AllocationPair &AP) const {
+    R->markInteresting(AP.first);
+    R->markInteresting(AP.second->Region);
+  }
 
   /// The bug visitor which allows us to print extra diagnostics along the
   /// BugReport path. For example, showing the allocation site of the leaked
@@ -282,6 +288,7 @@ void MacOSKeychainAPIChecker::
   BugReport *Report = new BugReport(*BT, os.str(), N);
   Report->addVisitor(new SecKeychainBugVisitor(AP.first));
   Report->addRange(ArgExpr->getSourceRange());
+  markInteresting(Report, AP);
   C.EmitReport(Report);
 }
 
@@ -318,6 +325,7 @@ void MacOSKeychainAPIChecker::checkPreStmt(const CallExpr *CE,
           BugReport *Report = new BugReport(*BT, os.str(), N);
           Report->addVisitor(new SecKeychainBugVisitor(V));
           Report->addRange(ArgExpr->getSourceRange());
+          Report->markInteresting(AS->Region);
           C.EmitReport(Report);
         }
       }
@@ -369,6 +377,8 @@ void MacOSKeychainAPIChecker::checkPreStmt(const CallExpr *CE,
     BugReport *Report = new BugReport(*BT,
         "Trying to free data which has not been allocated.", N);
     Report->addRange(ArgExpr->getSourceRange());
+    if (AS)
+      Report->markInteresting(AS->Region);
     C.EmitReport(Report);
     return;
   }
@@ -432,6 +442,7 @@ void MacOSKeychainAPIChecker::checkPreStmt(const CallExpr *CE,
         "Only call free if a valid (non-NULL) buffer was returned.", N);
     Report->addVisitor(new SecKeychainBugVisitor(ArgSM));
     Report->addRange(ArgExpr->getSourceRange());
+    Report->markInteresting(AS->Region);
     C.EmitReport(Report);
     return;
   }
@@ -550,6 +561,7 @@ BugReport *MacOSKeychainAPIChecker::
 
   BugReport *Report = new BugReport(*BT, os.str(), N, LocUsedForUniqueing);
   Report->addVisitor(new SecKeychainBugVisitor(AP.first));
+  markInteresting(Report, AP);
   return Report;
 }