[analyzer] Proper caching in CallDescription objects.

During the review of D29567 it turned out the caching in CallDescription is not implemented properly. In case an identifier does not exist in a translation unit, repeated identifier lookups will be done which might have bad impact on the performance. This patch guarantees that the lookup is only executed once. Moreover this patch fixes a corner case when the identifier of CallDescription does not exist in the translation unit and the called function does not have an identifier (e.g.: overloaded operator in C++).

Differential Revision: https://reviews.llvm.org/D29884

llvm-svn: 295186

1 files changed, 5 insertions, 2 deletions

diff --git a/clang/lib/StaticAnalyzer/Core/CallEvent.cpp b/clang/lib/StaticAnalyzer/Core/CallEvent.cpp
index af610395a87..ef824b8a3b1 100644
--- a/clang/lib/StaticAnalyzer/Core/CallEvent.cpp
+++ b/clang/lib/StaticAnalyzer/Core/CallEvent.cpp
@@ -212,9 +212,12 @@ ProgramPoint CallEvent::getProgramPoint(bool IsPreVisit,
 
 bool CallEvent::isCalled(const CallDescription &CD) const {
   assert(getKind() != CE_ObjCMessage && "Obj-C methods are not supported");
-  if (!CD.II)
+  if (!CD.IsLookupDone) {
+    CD.IsLookupDone = true;
     CD.II = &getState()->getStateManager().getContext().Idents.get(CD.FuncName);
-  if (getCalleeIdentifier() != CD.II)
+  }
+  const IdentifierInfo *II = getCalleeIdentifier();
+  if (!II || II != CD.II)
     return false;
   return (CD.RequiredArgs == CallDescription::NoArgRequirement ||
           CD.RequiredArgs == getNumArgs());