Merged master:e9f943429c8 into amd-gfx:f8416c3e42a

Local branch amd-gfx f8416c3 Merged master:edc7da24057 into amd-gfx:5925a948df2
Remote branch master e9f9434 [lldb] Skip TestIOHandlerResizeNoEditline on Windows

clang/docs/analyzer/checkers.rst

@@ -1836,6 +1836,19 @@ Check unreachable code.
    [x retain]; // warn
  }
 
+.. _alpha-cplusplus-SmartPtr:
+
+alpha.cplusplus.SmartPtr (C++)
+""""""""""""""""""""""""""""""
+Check for dereference of null smart pointers.
+
+.. code-block:: cpp
+
+ void deref_smart_ptr() {
+   std::unique_ptr<int> P;
+   *P; // warn: dereference of a default constructed smart unique_ptr
+ }
+
 alpha.llvm
 ^^^^^^^^^^
 

clang/include/clang/StaticAnalyzer/Checkers/Checkers.td

@@ -577,9 +577,17 @@ def CXXSelfAssignmentChecker : Checker<"SelfAssignment">,
   Documentation<NotDocumented>,
   Hidden;
 
-def SmartPtrModeling: Checker<"SmartPtr">,
+def SmartPtrModeling: Checker<"SmartPtrModeling">,
   HelpText<"Model behavior of C++ smart pointers">,
   Documentation<NotDocumented>,
+    CheckerOptions<[
+    CmdLineOption<Boolean,
+                  "ModelSmartPtrDereference",
+                  "Enable modeling for SmartPtr null dereferences",
+                  "false",
+                  InAlpha,
+                  Hide>,
+  ]>,
   Hidden;
 
 def MoveChecker: Checker<"Move">,
@@ -736,6 +744,11 @@ def MismatchedIteratorChecker : Checker<"MismatchedIterator">,
   Dependencies<[IteratorModeling]>,
   Documentation<HasAlphaDocumentation>;
 
+def SmartPtrChecker: Checker<"SmartPtr">,
+  HelpText<"Find the dereference of null SmrtPtr">,
+  Dependencies<[SmartPtrModeling]>,
+  Documentation<HasAlphaDocumentation>;
+
 } // end: "alpha.cplusplus"
 
 

clang/include/clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h

@@ -788,6 +788,10 @@ class CXXMemberOperatorCall : public CXXInstanceCall {
     // to implicit this-parameter on the declaration.
     return CallArgumentIndex + 1;
   }
+
+  OverloadedOperatorKind getOverloadedOperator() const {
+    return getOriginExpr()->getOperator();
+  }
 };
 
 /// Represents an implicit call to a C++ destructor.

clang/lib/StaticAnalyzer/Checkers/CMakeLists.txt

@@ -98,6 +98,7 @@ add_clang_library(clangStaticAnalyzerCheckers
   ReturnValueChecker.cpp
   RunLoopAutoreleaseLeakChecker.cpp
   SimpleStreamChecker.cpp
+  SmartPtrChecker.cpp
   SmartPtrModeling.cpp
   StackAddrEscapeChecker.cpp
   StdLibraryFunctionsChecker.cpp

clang/lib/StaticAnalyzer/Checkers/SmartPtr.h

@@ -0,0 +1,40 @@
+//=== SmartPtr.h - Tracking smart pointer state. -------------------*- C++ -*-//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// Defines inter-checker API for the smart pointer modeling. It allows
+// dependent checkers to figure out if an smart pointer is null or not.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_LIB_STATICANALYZER_CHECKERS_SMARTPTR_H
+#define LLVM_CLANG_LIB_STATICANALYZER_CHECKERS_SMARTPTR_H
+
+#include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h"
+
+namespace clang {
+namespace ento {
+namespace smartptr {
+
+/// Set of STL smart pointer class which we are trying to model.
+const llvm::StringSet<> StdSmartPtrs = {
+    "shared_ptr",
+    "unique_ptr",
+    "weak_ptr",
+};
+
+/// Returns true if the event call is on smart pointer.
+bool isStdSmartPtrCall(const CallEvent &Call);
+
+/// Returns whether the smart pointer is null or not.
+bool isNullSmartPtr(const ProgramStateRef State, const MemRegion *ThisRegion);
+
+} // namespace smartptr
+} // namespace ento
+} // namespace clang
+
+#endif // LLVM_CLANG_LIB_STATICANALYZER_CHECKERS_SMARTPTR_H

clang/lib/StaticAnalyzer/Checkers/SmartPtrChecker.cpp

@@ -0,0 +1,80 @@
+// SmartPtrChecker.cpp - Check for smart pointer dereference - C++ --------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines a checker that check for null dereference of C++ smart
+// pointer.
+//
+//===----------------------------------------------------------------------===//
+#include "SmartPtr.h"
+
+#include "clang/AST/DeclCXX.h"
+#include "clang/AST/ExprCXX.h"
+#include "clang/AST/Type.h"
+#include "clang/StaticAnalyzer/Checkers/BuiltinCheckerRegistration.h"
+#include "clang/StaticAnalyzer/Core/BugReporter/BugType.h"
+#include "clang/StaticAnalyzer/Core/Checker.h"
+#include "clang/StaticAnalyzer/Core/CheckerManager.h"
+#include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h"
+#include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h"
+#include "clang/StaticAnalyzer/Core/PathSensitive/SVals.h"
+#include "clang/StaticAnalyzer/Core/PathSensitive/SymExpr.h"
+
+using namespace clang;
+using namespace ento;
+
+namespace {
+class SmartPtrChecker : public Checker<check::PreCall> {
+  BugType NullDereferenceBugType{this, "Null SmartPtr dereference",
+                                 "C++ Smart Pointer"};
+
+public:
+  void checkPreCall(const CallEvent &Call, CheckerContext &C) const;
+
+private:
+  void reportBug(CheckerContext &C, const CallEvent &Call) const;
+};
+} // end of anonymous namespace
+
+void SmartPtrChecker::checkPreCall(const CallEvent &Call,
+                                   CheckerContext &C) const {
+  if (!smartptr::isStdSmartPtrCall(Call))
+    return;
+  ProgramStateRef State = C.getState();
+  const auto *OC = dyn_cast<CXXMemberOperatorCall>(&Call);
+  if (!OC)
+    return;
+  const MemRegion *ThisRegion = OC->getCXXThisVal().getAsRegion();
+  if (!ThisRegion)
+    return;
+
+  OverloadedOperatorKind OOK = OC->getOverloadedOperator();
+  if (OOK == OO_Star || OOK == OO_Arrow) {
+    if (smartptr::isNullSmartPtr(State, ThisRegion))
+      reportBug(C, Call);
+  }
+}
+
+void SmartPtrChecker::reportBug(CheckerContext &C,
+                                const CallEvent &Call) const {
+  ExplodedNode *ErrNode = C.generateErrorNode();
+  if (!ErrNode)
+    return;
+
+  auto R = std::make_unique<PathSensitiveBugReport>(
+      NullDereferenceBugType, "Dereference of null smart pointer", ErrNode);
+  C.emitReport(std::move(R));
+}
+
+void ento::registerSmartPtrChecker(CheckerManager &Mgr) {
+  Mgr.registerChecker<SmartPtrChecker>();
+}
+
+bool ento::shouldRegisterSmartPtrChecker(const CheckerManager &mgr) {
+  const LangOptions &LO = mgr.getLangOpts();
+  return LO.CPlusPlus;
+}