[analyzer] Process state in checkEndFunction in RetainCountChecker

Modify the RetainCountChecker to perform state "adjustments" in
checkEndFunction, as performing work in PreStmt<ReturnStmt> does not
work with destructors.
The previous version made an implicit assumption that no code runs
after the return statement is executed.

rdar://43945028

Differential Revision: https://reviews.llvm.org/D52338

llvm-svn: 342770

1 files changed, 10 insertions, 4 deletions

diff --git a/clang/lib/StaticAnalyzer/Checkers/RetainCountChecker/RetainCountChecker.h b/clang/lib/StaticAnalyzer/Checkers/RetainCountChecker/RetainCountChecker.h
index 8683b23dd96..e8d9136ffd2 100644
--- a/clang/lib/StaticAnalyzer/Checkers/RetainCountChecker/RetainCountChecker.h
+++ b/clang/lib/StaticAnalyzer/Checkers/RetainCountChecker/RetainCountChecker.h
@@ -252,7 +252,6 @@ class RetainCountChecker
                     check::PostStmt<ObjCBoxedExpr>,
                     check::PostStmt<ObjCIvarRefExpr>,
                     check::PostCall,
-                    check::PreStmt<ReturnStmt>,
                     check::RegionChanges,
                     eval::Assume,
                     eval::Call > {
@@ -388,8 +387,7 @@ public:
                      const LocationContext* LCtx,
                      const CallEvent *Call) const;
 
-  void checkPreStmt(const ReturnStmt *S, CheckerContext &C) const;
-  void checkReturnWithRetEffect(const ReturnStmt *S, CheckerContext &C,
+  ExplodedNode* checkReturnWithRetEffect(const ReturnStmt *S, CheckerContext &C,
                                 ExplodedNode *Pred, RetEffect RE, RefVal X,
                                 SymbolRef Sym, ProgramStateRef state) const;
 
@@ -416,12 +414,20 @@ public:
   ProgramStateRef
   handleAutoreleaseCounts(ProgramStateRef state, ExplodedNode *Pred,
                           const ProgramPointTag *Tag, CheckerContext &Ctx,
-                          SymbolRef Sym, RefVal V) const;
+                          SymbolRef Sym,
+                          RefVal V,
+                          const ReturnStmt *S=nullptr) const;
 
   ExplodedNode *processLeaks(ProgramStateRef state,
                              SmallVectorImpl<SymbolRef> &Leaked,
                              CheckerContext &Ctx,
                              ExplodedNode *Pred = nullptr) const;
+
+private:
+  /// Perform the necessary checks and state adjustments at the end of the
+  /// function.
+  /// \p S Return statement, may be null.
+  ExplodedNode * processReturn(const ReturnStmt *S, CheckerContext &C) const;
 };
 
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