[PATCH] [analyzer] Add very limited support for temporary destructors

[Pavel Labath]

  Pass NULL to VisitCXXDestructor, add tests

  I added some analyzer tests that check that noreturn destructors really do not
  return, and a couple of tests that verify the constructed CFG.

Hi jordan_rose,

http://llvm-reviews.chandlerc.com/D1131

CHANGE SINCE LAST DIFF
  http://llvm-reviews.chandlerc.com/D1131?vs=2776&id=2829#toc

Files:
  lib/StaticAnalyzer/Core/AnalyzerOptions.cpp
  lib/StaticAnalyzer/Core/ExprEngine.cpp
  lib/StaticAnalyzer/Core/ExprEngineCallAndReturn.cpp
  test/Analysis/analyzer-config.c
  test/Analysis/analyzer-config.cpp
  test/Analysis/dtor.cpp
  test/Analysis/temp-obj-dtors-cfg-output.cpp

Index: lib/StaticAnalyzer/Core/AnalyzerOptions.cpp
===================================================================
--- lib/StaticAnalyzer/Core/AnalyzerOptions.cpp
+++ lib/StaticAnalyzer/Core/AnalyzerOptions.cpp
@@ -119,7 +119,7 @@
 bool AnalyzerOptions::includeTemporaryDtorsInCFG() {
   return getBooleanOption(IncludeTemporaryDtorsInCFG,
                           "cfg-temporary-dtors",
-                          /* Default = */ false);
+                          /* Default = */ true);
 }
 
 bool AnalyzerOptions::mayInlineCXXStandardLibrary() {
Index: lib/StaticAnalyzer/Core/ExprEngine.cpp
===================================================================
--- lib/StaticAnalyzer/Core/ExprEngine.cpp
+++ lib/StaticAnalyzer/Core/ExprEngine.cpp
@@ -589,7 +589,15 @@
 
 void ExprEngine::ProcessTemporaryDtor(const CFGTemporaryDtor D,
                                       ExplodedNode *Pred,
-                                      ExplodedNodeSet &Dst) {}
+                                      ExplodedNodeSet &Dst) {
+
+  QualType varType = D.getBindTemporaryExpr()->getSubExpr()->getType();
+
+  // FIXME: Inlining of temporary destructors is not supported yet anyway, so we
+  // just put a NULL region for now. This will need to be changed later.
+  VisitCXXDestructor(varType, NULL, D.getBindTemporaryExpr(),
+                     /*IsBase=*/ false, Pred, Dst);
+}
 
 void ExprEngine::Visit(const Stmt *S, ExplodedNode *Pred,
                        ExplodedNodeSet &DstTop) {
Index: lib/StaticAnalyzer/Core/ExprEngineCallAndReturn.cpp
===================================================================
--- lib/StaticAnalyzer/Core/ExprEngineCallAndReturn.cpp
+++ lib/StaticAnalyzer/Core/ExprEngineCallAndReturn.cpp
@@ -804,6 +804,12 @@
   AnalysisDeclContextManager &ADCMgr = AMgr.getAnalysisDeclContextManager();
   AnalysisDeclContext *CalleeADC = ADCMgr.getContext(D);
 
+  // Temporary object destructor processing is currently broken, so we never
+  // inline them.
+  // FIME: Remove this once temp destructors are working.
+  if ((*currBldrCtx->getBlock())[currStmtIdx].getAs<CFGTemporaryDtor>())
+    return false;
+
   // The auto-synthesized bodies are essential to inline as they are
   // usually small and commonly used. Note: we should do this check early on to
   // ensure we always inline these calls.
Index: test/Analysis/analyzer-config.c
===================================================================
--- test/Analysis/analyzer-config.c
+++ test/Analysis/analyzer-config.c
@@ -6,7 +6,7 @@
 
 // CHECK: [config]
 // CHECK-NEXT: cfg-conditional-static-initializers = true
-// CHECK-NEXT: cfg-temporary-dtors = false
+// CHECK-NEXT: cfg-temporary-dtors = true
 // CHECK-NEXT: faux-bodies = true
 // CHECK-NEXT: graph-trim-interval = 1000
 // CHECK-NEXT: ipa = dynamic-bifurcate
Index: test/Analysis/analyzer-config.cpp
===================================================================
--- test/Analysis/analyzer-config.cpp
+++ test/Analysis/analyzer-config.cpp
@@ -17,7 +17,7 @@
 // CHECK-NEXT: c++-stdlib-inlining = true
 // CHECK-NEXT: c++-template-inlining = true
 // CHECK-NEXT: cfg-conditional-static-initializers = true
-// CHECK-NEXT: cfg-temporary-dtors = false
+// CHECK-NEXT: cfg-temporary-dtors = true
 // CHECK-NEXT: faux-bodies = true
 // CHECK-NEXT: graph-trim-interval = 1000
 // CHECK-NEXT: ipa = dynamic-bifurcate
Index: test/Analysis/dtor.cpp
===================================================================
--- test/Analysis/dtor.cpp
+++ test/Analysis/dtor.cpp
@@ -416,4 +416,19 @@
     f(&x);
     *x = 47; // no warning
   }
+
+  void g2(int *x) {
+    if (! x) NR();
+    *x = 47; // no warning
+  }
+
+  void f3(int **x) {
+    NR();
+  }
+
+  void g3() {
+    int *x;
+    f3(&x);
+    *x = 47; // no warning
+  }
 }
Index: test/Analysis/temp-obj-dtors-cfg-output.cpp
===================================================================
--- test/Analysis/temp-obj-dtors-cfg-output.cpp
+++ test/Analysis/temp-obj-dtors-cfg-output.cpp
@@ -108,6 +108,24 @@
   : a(int(A()) + int(B()))
   , b() {}
 
+class NoReturn {
+public:
+  ~NoReturn() __attribute__((noreturn));
+  void f();
+};
+
+void test_noreturn1() {
+  int a;
+  NoReturn().f();
+  int b;
+}
+
+void test_noreturn2() {
+  int a;
+  NoReturn(), 47;
+  int b;
+}
+
 // CHECK:   [B1 (ENTRY)]
 // CHECK:     Succs (1): B0
 // CHECK:   [B0 (EXIT)]
@@ -846,3 +864,36 @@
 // CHECK:   [B0 (EXIT)]
 // CHECK:     Preds (1): B1
 
+// CHECK:   [B3 (ENTRY)]
+// CHECK:     Succs (1): B2
+// CHECK:   [B1]
+// CHECK:     1: int b;
+// CHECK:     Succs (1): B0
+// CHECK:   [B2]
+// CHECK:     1: int a;
+// CHECK:     2: NoReturn() (CXXConstructExpr, class NoReturn)
+// CHECK:     3: [B2.2] (BindTemporary)
+// CHECK:     4: [B2.3].f
+// CHECK:     5: [B2.4]()
+// CHECK:     6: ~NoReturn() (Temporary object destructor)
+// CHECK:     Preds (1): B3
+// CHECK:     Succs (1): B0
+// CHECK:   [B0 (EXIT)]
+// CHECK:     Preds (2): B1 B2
+
+// CHECK:   [B3 (ENTRY)]
+// CHECK:     Succs (1): B2
+// CHECK:   [B1]
+// CHECK:     1: int b;
+// CHECK:     Succs (1): B0
+// CHECK:   [B2]
+// CHECK:     1: int a;
+// CHECK:     2: NoReturn() (CXXConstructExpr, class NoReturn)
+// CHECK:     3: [B2.2] (BindTemporary)
+// CHECK:     4: 47
+// CHECK:     5: ... , [B2.4]
+// CHECK:     6: ~NoReturn() (Temporary object destructor)
+// CHECK:     Preds (1): B3
+// CHECK:     Succs (1): B0
+// CHECK:   [B0 (EXIT)]
+// CHECK:     Preds (2): B1 B2
-------------- next part --------------
A non-text attachment was scrubbed...
Name: D1131.2.patch
Type: text/x-patch
Size: 5454 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/cfe-commits/attachments/20130716/c04ac133/attachment.bin>