[analyzer] Obtain a ReturnStmt from a CFGAutomaticObjDtor.

The CoreEngine only gives us a ReturnStmt if the last element in the
CFGBlock is a CFGStmt, otherwise the ReturnStmt is nullptr.
This patch adds support for the case when the last element is a
CFGAutomaticObjDtor, by returning its TriggerStmt as a ReturnStmt.

Differential Revision: https://reviews.llvm.org/D49811

llvm-svn: 338777

1 files changed, 34 insertions, 0 deletions

diff --git a/clang/test/Analysis/end-function-return-stmt.cpp b/clang/test/Analysis/end-function-return-stmt.cpp
new file mode 100644
index 00000000000..036ccba3aa9
--- /dev/null
+++ b/clang/test/Analysis/end-function-return-stmt.cpp
@@ -0,0 +1,34 @@
+//RUN: %clang_analyze_cc1 -analyzer-checker=debug.AnalysisOrder -analyzer-config debug.AnalysisOrder:EndFunction=true %s 2>&1 | FileCheck %s
+
+// At the end of a function, we can only obtain a ReturnStmt if the last
+// CFGElement in the CFGBlock is either a CFGStmt or a CFGAutomaticObjDtor.
+
+void noReturnStmt() {}
+
+struct S {
+  S();
+  ~S();
+};
+
+int dtorAfterReturnStmt() {
+  S s;
+  return 0;
+}
+
+S endsWithReturnStmt() {
+  return S();
+}
+
+// endsWithReturnStmt()
+// CHECK:      EndFunction
+// CHECK-NEXT: ReturnStmt: yes
+// CHECK-NEXT: CFGElement: CFGStmt
+
+// dtorAfterReturnStmt()
+// CHECK:      EndFunction
+// CHECK-NEXT: ReturnStmt: yes
+// CHECK-NEXT: CFGElement: CFGAutomaticObjDtor
+
+// noReturnStmt()
+// CHECK:      EndFunction
+// CHECK-NEXT: ReturnStmt: no