[analyzer] Add a new abstraction over all types of calls: CallEvent

This is intended to replace CallOrObjCMessage, and is eventually intended to be
used for anything that cares more about /what/ is being called than /how/ it's
being called. For example, inlining destructors should be the same as inlining
blocks, and checking __attribute__((nonnull)) should apply to the allocator
calls generated by operator new.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@159554 91177308-0d34-0410-b5e6-96231b3b80d8

13 files changed, 510 insertions, 325 deletions

diff --git a/lib/StaticAnalyzer/Checkers/CStringChecker.cpp b/lib/StaticAnalyzer/Checkers/CStringChecker.cpp
index 942280d03d..69373749a2 100644
--- a/lib/StaticAnalyzer/Checkers/CStringChecker.cpp
+++ b/lib/StaticAnalyzer/Checkers/CStringChecker.cpp
@@ -66,7 +66,7 @@ public:
                        const StoreManager::InvalidatedSymbols *,
                        ArrayRef<const MemRegion *> ExplicitRegions,
                        ArrayRef<const MemRegion *> Regions,
-                       const CallOrObjCMessage *Call) const;
+                       const CallEvent *Call) const;
 
   typedef void (CStringChecker::*FnCheck)(CheckerContext &,
                                           const CallExpr *) const;
@@ -1895,7 +1895,7 @@ CStringChecker::checkRegionChanges(ProgramStateRef state,
                                    const StoreManager::InvalidatedSymbols *,
                                    ArrayRef<const MemRegion *> ExplicitRegions,
                                    ArrayRef<const MemRegion *> Regions,
-                                   const CallOrObjCMessage *Call) const {
+                                   const CallEvent *Call) const {
   CStringLength::EntryMap Entries = state->get<CStringLength>();
   if (Entries.isEmpty())
     return state;
diff --git a/lib/StaticAnalyzer/Checkers/CheckerDocumentation.cpp b/lib/StaticAnalyzer/Checkers/CheckerDocumentation.cpp
index 8d46e5ec30..61582d028a 100644
--- a/lib/StaticAnalyzer/Checkers/CheckerDocumentation.cpp
+++ b/lib/StaticAnalyzer/Checkers/CheckerDocumentation.cpp
@@ -206,7 +206,7 @@ public:
                        const StoreManager::InvalidatedSymbols *Invalidated,
                        ArrayRef<const MemRegion *> ExplicitRegions,
                        ArrayRef<const MemRegion *> Regions,
-                       const CallOrObjCMessage *Call) const {
+                       const CallEvent *Call) const {
     return State;
   }
 
diff --git a/lib/StaticAnalyzer/Checkers/MallocChecker.cpp b/lib/StaticAnalyzer/Checkers/MallocChecker.cpp
index 1aa9b824e3..0e13ddcd7e 100644
--- a/lib/StaticAnalyzer/Checkers/MallocChecker.cpp
+++ b/lib/StaticAnalyzer/Checkers/MallocChecker.cpp
@@ -18,7 +18,7 @@
 #include "clang/StaticAnalyzer/Core/CheckerManager.h"
 #include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h"
 #include "clang/StaticAnalyzer/Core/BugReporter/BugType.h"
-#include "clang/StaticAnalyzer/Core/PathSensitive/ObjCMessage.h"
+#include "clang/StaticAnalyzer/Core/PathSensitive/Calls.h"
 #include "clang/StaticAnalyzer/Core/PathSensitive/ProgramState.h"
 #include "clang/StaticAnalyzer/Core/PathSensitive/ProgramStateTrait.h"
 #include "clang/StaticAnalyzer/Core/PathSensitive/SymbolManager.h"
@@ -140,7 +140,7 @@ public:
                      const StoreManager::InvalidatedSymbols *invalidated,
                      ArrayRef<const MemRegion *> ExplicitRegions,
                      ArrayRef<const MemRegion *> Regions,
-                     const CallOrObjCMessage *Call) const;
+                     const CallEvent *Call) const;
   bool wantsRegionChangeUpdate(ProgramStateRef state) const {
     return true;
   }
@@ -200,7 +200,7 @@ private:
 
   /// Check if the function is not known to us. So, for example, we could
   /// conservatively assume it can free/reallocate it's pointer arguments.
-  bool doesNotFreeMemory(const CallOrObjCMessage *Call,
+  bool doesNotFreeMemory(const CallEvent *Call,
                          ProgramStateRef State) const;
 
   static bool SummarizeValue(raw_ostream &os, SVal V);
@@ -481,7 +481,8 @@ void MallocChecker::checkPostStmt(const CallExpr *CE, CheckerContext &C) const {
   C.addTransition(State);
 }
 
-static bool isFreeWhenDoneSetToZero(CallOrObjCMessage Call, Selector &S) {
+static bool isFreeWhenDoneSetToZero(const ObjCMessageInvocation &Call,
+                                    Selector &S) {
   for (unsigned i = 1; i < S.getNumArgs(); ++i)
     if (S.getNameForSlot(i).equals("freeWhenDone"))
       if (Call.getArgSVal(i).isConstant(0))
@@ -491,12 +492,12 @@ static bool isFreeWhenDoneSetToZero(CallOrObjCMessage Call, Selector &S) {
 }
 
 void MallocChecker::checkPreObjCMessage(const ObjCMessage &Msg,
-                                         CheckerContext &C) const {
+                                        CheckerContext &C) const {
   const ObjCMethodDecl *MD = Msg.getMethodDecl();
   if (!MD)
     return;
 
-  CallOrObjCMessage Call(Msg, C.getState(), C.getLocationContext());
+  ObjCMessageInvocation Call(Msg, C.getState(), C.getLocationContext());
   Selector S = Msg.getSelector();
 
   // If the first selector is dataWithBytesNoCopy, assume that the memory will
@@ -509,7 +510,7 @@ void MallocChecker::checkPreObjCMessage(const ObjCMessage &Msg,
        S.getNameForSlot(0) == "initWithCharactersNoCopy") &&
       !isFreeWhenDoneSetToZero(Call, S)){
     unsigned int argIdx  = 0;
-    C.addTransition(FreeMemAux(C, Call.getArg(argIdx),
+    C.addTransition(FreeMemAux(C, Call.getArgExpr(argIdx),
                     Msg.getMessageExpr(), C.getState(), true));
   }
 }
@@ -1310,10 +1311,10 @@ ProgramStateRef MallocChecker::evalAssume(ProgramStateRef state,
 }
 
 // Check if the function is known to us. So, for example, we could
-// conservatively assume it can free/reallocate it's pointer arguments.
+// conservatively assume it can free/reallocate its pointer arguments.
 // (We assume that the pointers cannot escape through calls to system
 // functions not handled by this checker.)
-bool MallocChecker::doesNotFreeMemory(const CallOrObjCMessage *Call,
+bool MallocChecker::doesNotFreeMemory(const CallEvent *Call,
                                       ProgramStateRef State) const {
   if (!Call)
     return false;
@@ -1322,118 +1323,23 @@ bool MallocChecker::doesNotFreeMemory(const CallOrObjCMessage *Call,
   // TODO: If we want to be more optimistic here, we'll need to make sure that
   // regions escape to C++ containers. They seem to do that even now, but for
   // mysterious reasons.
-  if (Call->isCXXCall())
+  if (!(isa<FunctionCall>(Call) || isa<ObjCMessageInvocation>(Call)))
     return false;
 
-  const Decl *D = Call->getDecl();
-  if (!D)
+  // If the call has a callback as an argument, assume the memory
+  // can be freed.
+  if (Call->hasNonZeroCallbackArg())
     return false;
 
-  ASTContext &ASTC = State->getStateManager().getContext();
-
-  // If it's one of the allocation functions we can reason about, we model
-  // its behavior explicitly.
-  if (isa<FunctionDecl>(D) && isMemFunction(cast<FunctionDecl>(D), ASTC)) {
-    return true;
-  }
-
-  // If it's not a system call, assume it frees memory.
-  if (!Call->isInSystemHeader())
-    return false;
-
-  // Process C/ObjC functions.
-  if (const FunctionDecl *FD  = dyn_cast<FunctionDecl>(D)) {
-    // White list the system functions whose arguments escape.
-    const IdentifierInfo *II = FD->getIdentifier();
-    if (!II)
-      return true;
-    StringRef FName = II->getName();
-
-    // White list thread local storage.
-    if (FName.equals("pthread_setspecific"))
-      return false;
-
-    // White list xpc connection context.
-    // TODO: Ensure that the deallocation actually happens, need to reason
-    // about "xpc_connection_set_finalizer_f".
-    if (FName.equals("xpc_connection_set_context"))
-      return false;
-
-    // White list the 'XXXNoCopy' ObjC functions.
-    if (FName.endswith("NoCopy")) {
-      // Look for the deallocator argument. We know that the memory ownership
-      // is not transferred only if the deallocator argument is
-      // 'kCFAllocatorNull'.
-      for (unsigned i = 1; i < Call->getNumArgs(); ++i) {
-        const Expr *ArgE = Call->getArg(i)->IgnoreParenCasts();
-        if (const DeclRefExpr *DE = dyn_cast<DeclRefExpr>(ArgE)) {
-          StringRef DeallocatorName = DE->getFoundDecl()->getName();
-          if (DeallocatorName == "kCFAllocatorNull")
-            return true;
-        }
-      }
-      return false;
-    }
-
-    // PR12101
-    // Many CoreFoundation and CoreGraphics might allow a tracked object 
-    // to escape.
-    if (Call->isCFCGAllowingEscape(FName))
-      return false;
-
-    // Associating streams with malloced buffers. The pointer can escape if
-    // 'closefn' is specified (and if that function does free memory).
-    // Currently, we do not inspect the 'closefn' function (PR12101).
-    if (FName == "funopen")
-      if (Call->getNumArgs() >= 4 && !Call->getArgSVal(4).isConstant(0))
-        return false;
-
-    // Do not warn on pointers passed to 'setbuf' when used with std streams,
-    // these leaks might be intentional when setting the buffer for stdio.
-    // http://stackoverflow.com/questions/2671151/who-frees-setvbuf-buffer
-    if (FName == "setbuf" || FName =="setbuffer" ||
-        FName == "setlinebuf" || FName == "setvbuf") {
-      if (Call->getNumArgs() >= 1)
-        if (const DeclRefExpr *Arg =
-              dyn_cast<DeclRefExpr>(Call->getArg(0)->IgnoreParenCasts()))
-          if (const VarDecl *D = dyn_cast<VarDecl>(Arg->getDecl()))
-              if (D->getCanonicalDecl()->getName().find("std")
-                                                   != StringRef::npos)
-                return false;
-    }
-
-    // A bunch of other functions which either take ownership of a pointer or
-    // wrap the result up in a struct or object, meaning it can be freed later.
-    // (See RetainCountChecker.) Not all the parameters here are invalidated,
-    // but the Malloc checker cannot differentiate between them. The right way
-    // of doing this would be to implement a pointer escapes callback.
-    if (FName == "CGBitmapContextCreate" ||
-        FName == "CGBitmapContextCreateWithData" ||
-        FName == "CVPixelBufferCreateWithBytes" ||
-        FName == "CVPixelBufferCreateWithPlanarBytes" ||
-        FName == "OSAtomicEnqueue") {
-      return false;
-    }
-
-    // Whitelist NSXXInsertXX, for example NSMapInsertIfAbsent, since they can
-    // be deallocated by NSMapRemove.
-    if (FName.startswith("NS") && (FName.find("Insert") != StringRef::npos))
+  // Check Objective-C messages by selector name.
+  if (const ObjCMessageInvocation *Msg = dyn_cast<ObjCMessageInvocation>(Call)){
+    // If it's not a framework call, assume it frees memory.
+    if (!Call->isInSystemHeader())
       return false;
 
-    // If the call has a callback as an argument, assume the memory
-    // can be freed.
-    if (Call->hasNonZeroCallbackArg())
-      return false;
-
-    // Otherwise, assume that the function does not free memory.
-    // Most system calls, do not free the memory.
-    return true;
+    Selector S = Msg->getSelector();
 
-  // Process ObjC functions.
-  } else if (const ObjCMethodDecl * ObjCD = dyn_cast<ObjCMethodDecl>(D)) {
-    Selector S = ObjCD->getSelector();
-
-    // White list the ObjC functions which do free memory.
+    // Whitelist the ObjC methods which do free memory.
     // - Anything containing 'freeWhenDone' param set to 1.
     //   Ex: dataWithBytesNoCopy:length:freeWhenDone.
     for (unsigned i = 1; i < S.getNumArgs(); ++i) {
@@ -1448,33 +1354,117 @@ bool MallocChecker::doesNotFreeMemory(const CallOrObjCMessage *Call,
     // If the first selector ends with NoCopy, assume that the ownership is
     // transferred as well.
     // Ex:  [NSData dataWithBytesNoCopy:bytes length:10];
-    if (S.getNameForSlot(0).endswith("NoCopy")) {
+    StringRef FirstSlot = S.getNameForSlot(0);
+    if (FirstSlot.endswith("NoCopy"))
       return false;
-    }
 
     // If the first selector starts with addPointer, insertPointer,
     // or replacePointer, assume we are dealing with NSPointerArray or similar.
     // This is similar to C++ containers (vector); we still might want to check
-    // that the pointers get freed, by following the container itself.
-    if (S.getNameForSlot(0).startswith("addPointer") ||
-        S.getNameForSlot(0).startswith("insertPointer") ||
-        S.getNameForSlot(0).startswith("replacePointer")) {
+    // that the pointers get freed by following the container itself.
+    if (FirstSlot.startswith("addPointer") ||
+        FirstSlot.startswith("insertPointer") ||
+        FirstSlot.startswith("replacePointer")) {
       return false;
     }
 
-    // If the call has a callback as an argument, assume the memory
-    // can be freed.
-    if (Call->hasNonZeroCallbackArg())
-      return false;
+    // Otherwise, assume that the method does not free memory.
+    // Most framework methods do not free memory.
+    return true;
+  }
 
-    // Otherwise, assume that the function does not free memory.
-    // Most system calls, do not free the memory.
+  // At this point the only thing left to handle is straight function calls.
+  const FunctionDecl *FD = cast<FunctionCall>(Call)->getDecl();
+  if (!FD)
+    return false;
+
+  ASTContext &ASTC = State->getStateManager().getContext();
+
+  // If it's one of the allocation functions we can reason about, we model
+  // its behavior explicitly.
+  if (isMemFunction(FD, ASTC))
     return true;
+
+  // If it's not a system call, assume it frees memory.
+  if (!Call->isInSystemHeader())
+    return false;
+
+  // White list the system functions whose arguments escape.
+  const IdentifierInfo *II = FD->getIdentifier();
+  if (!II)
+    return false;
+  StringRef FName = II->getName();
+
+  // White list thread local storage.
+  if (FName.equals("pthread_setspecific"))
+    return false;
+  if (FName.equals("xpc_connection_set_context"))
+    return false;
+
+  // White list the 'XXXNoCopy' CoreFoundation functions.
+  if (FName.endswith("NoCopy")) {
+    // Look for the deallocator argument. We know that the memory ownership
+    // is not transferred only if the deallocator argument is
+    // 'kCFAllocatorNull'.
+    for (unsigned i = 1; i < Call->getNumArgs(); ++i) {
+      const Expr *ArgE = Call->getArgExpr(i)->IgnoreParenCasts();
+      if (const DeclRefExpr *DE = dyn_cast<DeclRefExpr>(ArgE)) {
+        StringRef DeallocatorName = DE->getFoundDecl()->getName();
+        if (DeallocatorName == "kCFAllocatorNull")
+          return true;
+      }
+    }
+    return false;
   }
 
-  // Otherwise, assume that the function can free memory.
-  return false;
+  // PR12101
+  // Many CoreFoundation and CoreGraphics might allow a tracked object
+  // to escape.
+  if (CallOrObjCMessage::isCFCGAllowingEscape(FName))
+    return false;
+
+  // Associating streams with malloced buffers. The pointer can escape if
+  // 'closefn' is specified (and if that function does free memory).
+  // Currently, we do not inspect the 'closefn' function (PR12101).
+  if (FName == "funopen")
+    if (Call->getNumArgs() >= 4 && !Call->getArgSVal(4).isConstant(0))
+      return false;
 
+  // Do not warn on pointers passed to 'setbuf' when used with std streams,
+  // these leaks might be intentional when setting the buffer for stdio.
+  // http://stackoverflow.com/questions/2671151/who-frees-setvbuf-buffer
+  if (FName == "setbuf" || FName =="setbuffer" ||
+      FName == "setlinebuf" || FName == "setvbuf") {
+    if (Call->getNumArgs() >= 1) {
+      const Expr *ArgE = Call->getArgExpr(0)->IgnoreParenCasts();
+      if (const DeclRefExpr *ArgDRE = dyn_cast<DeclRefExpr>(ArgE))
+        if (const VarDecl *D = dyn_cast<VarDecl>(ArgDRE->getDecl()))
+          if (D->getCanonicalDecl()->getName().find("std") != StringRef::npos)
+            return false;
+    }
+  }
+
+  // A bunch of other functions which either take ownership of a pointer or
+  // wrap the result up in a struct or object, meaning it can be freed later.
+  // (See RetainCountChecker.) Not all the parameters here are invalidated,
+  // but the Malloc checker cannot differentiate between them. The right way
+  // of doing this would be to implement a pointer escapes callback.
+  if (FName == "CGBitmapContextCreate" ||
+      FName == "CGBitmapContextCreateWithData" ||
+      FName == "CVPixelBufferCreateWithBytes" ||
+      FName == "CVPixelBufferCreateWithPlanarBytes" ||
+      FName == "OSAtomicEnqueue") {
+    return false;
+  }
+
+  // Whitelist NSXXInsertXX, for example NSMapInsertIfAbsent, since they can
+  // be deallocated by NSMapRemove.
+  if (FName.startswith("NS") && (FName.find("Insert") != StringRef::npos))
+    return false;
+
+  // Otherwise, assume that the function does not free memory.
+  // Most system calls do not free the memory.
+  return true;
 }
 
 // If the symbol we are tracking is invalidated, but not explicitly (ex: the &p
@@ -1485,7 +1475,7 @@ MallocChecker::checkRegionChanges(ProgramStateRef State,
                             const StoreManager::InvalidatedSymbols *invalidated,
                                     ArrayRef<const MemRegion *> ExplicitRegions,
                                     ArrayRef<const MemRegion *> Regions,
-                                    const CallOrObjCMessage *Call) const {
+                                    const CallEvent *Call) const {
   if (!invalidated || invalidated->empty())
     return State;
   llvm::SmallPtrSet<SymbolRef, 8> WhitelistedSymbols;
diff --git a/lib/StaticAnalyzer/Checkers/RetainCountChecker.cpp b/lib/StaticAnalyzer/Checkers/RetainCountChecker.cpp
index 6da8833b33..098c464eef 100644
--- a/lib/StaticAnalyzer/Checkers/RetainCountChecker.cpp
+++ b/lib/StaticAnalyzer/Checkers/RetainCountChecker.cpp
@@ -2500,7 +2500,7 @@ public:
                      const StoreManager::InvalidatedSymbols *invalidated,
                      ArrayRef<const MemRegion *> ExplicitRegions,
                      ArrayRef<const MemRegion *> Regions,
-                     const CallOrObjCMessage *Call) const;
+                     const CallEvent *Call) const;
                                         
   bool wantsRegionChangeUpdate(ProgramStateRef state) const {
     return true;
@@ -3454,7 +3454,7 @@ RetainCountChecker::checkRegionChanges(ProgramStateRef state,
                             const StoreManager::InvalidatedSymbols *invalidated,
                                     ArrayRef<const MemRegion *> ExplicitRegions,
                                     ArrayRef<const MemRegion *> Regions,
-                                    const CallOrObjCMessage *Call) const {
+                                    const CallEvent *Call) const {
   if (!invalidated)
     return state;
 
diff --git a/lib/StaticAnalyzer/Core/CMakeLists.txt b/lib/StaticAnalyzer/Core/CMakeLists.txt
index 3da91788c6..0061ce1045 100644
--- a/lib/StaticAnalyzer/Core/CMakeLists.txt
+++ b/lib/StaticAnalyzer/Core/CMakeLists.txt
@@ -8,6 +8,7 @@ add_clang_library(clangStaticAnalyzerCore
   BlockCounter.cpp
   BugReporter.cpp
   BugReporterVisitors.cpp
+  Calls.cpp
   Checker.cpp
   CheckerContext.cpp
   CheckerHelpers.cpp
diff --git a/lib/StaticAnalyzer/Core/Calls.cpp b/lib/StaticAnalyzer/Core/Calls.cpp
new file mode 100644
index 0000000000..ea28cfdf36
--- /dev/null
+++ b/lib/StaticAnalyzer/Core/Calls.cpp
@@ -0,0 +1,353 @@
+//===- Calls.cpp - Wrapper for all function and method calls ------*- C++ -*--//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+/// \file This file defines CallEvent and its subclasses, which represent path-
+/// sensitive instances of different kinds of function and method calls
+/// (C, C++, and Objective-C).
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/StaticAnalyzer/Core/PathSensitive/Calls.h"
+#include "clang/StaticAnalyzer/Core/PathSensitive/ObjCMessage.h"
+#include "llvm/ADT/SmallSet.h"
+
+using namespace clang;
+using namespace ento;
+
+SVal CallEvent::getArgSVal(unsigned Index) const {
+  const Expr *ArgE = getArgExpr(Index);
+  if (!ArgE)
+    return UnknownVal();
+  return getSVal(ArgE);
+}
+
+SourceRange CallEvent::getArgSourceRange(unsigned Index) const {
+  const Expr *ArgE = getArgExpr(Index);
+  if (!ArgE)
+    return SourceRange();
+  return ArgE->getSourceRange();
+}
+
+QualType CallEvent::getResultType() const {
+  QualType ResultTy = getDeclaredResultType();
+
+  if (const Expr *E = getOriginExpr()) {
+    if (ResultTy.isNull())
+      ResultTy = E->getType();
+
+    // FIXME: This is copied from CallOrObjCMessage, but it seems suspicious.
+    if (E->isGLValue()) {
+      ASTContext &Ctx = State->getStateManager().getContext();
+      ResultTy = Ctx.getPointerType(ResultTy);
+    }
+  }
+
+  return ResultTy;
+}
+
+static bool isCallbackArg(SVal V, QualType T) {
+  // If the parameter is 0, it's harmless.
+  if (V.isZeroConstant())
+    return false;
+
+  // If a parameter is a block or a callback, assume it can modify pointer.
+  if (T->isBlockPointerType() ||
+      T->isFunctionPointerType() ||
+      T->isObjCSelType())
+    return true;
+
+  // Check if a callback is passed inside a struct (for both, struct passed by
+  // reference and by value). Dig just one level into the struct for now.
+
+  if (isa<PointerType>(T) || isa<ReferenceType>(T))
+    T = T->getPointeeType();
+
+  if (const RecordType *RT = T->getAsStructureType()) {
+    const RecordDecl *RD = RT->getDecl();
+    for (RecordDecl::field_iterator I = RD->field_begin(), E = RD->field_end();
+         I != E; ++I) {
+      QualType FieldT = I->getType();
+      if (FieldT->isBlockPointerType() || FieldT->isFunctionPointerType())
+        return true;
+    }
+  }
+
+  return false;
+}
+
+bool CallEvent::hasNonZeroCallbackArg() const {
+  unsigned NumOfArgs = getNumArgs();
+
+  // If calling using a function pointer, assume the function does not
+  // have a callback. TODO: We could check the types of the arguments here.
+  if (!getDecl())
+    return false;
+
+  unsigned Idx = 0;
+  for (CallEvent::param_type_iterator I = param_type_begin(),
+                                       E = param_type_end();
+       I != E && Idx < NumOfArgs; ++I, ++Idx) {
+    if (NumOfArgs <= Idx)
+      break;
+
+    if (isCallbackArg(getArgSVal(Idx), *I))
+      return true;
+  }
+  
+  return false;
+}
+
+/// \brief Returns true if a type is a pointer-to-const or reference-to-const
+/// with no further indirection.
+static bool isPointerToConst(QualType Ty) {
+  QualType PointeeTy = Ty->getPointeeType();
+  if (PointeeTy == QualType())
+    return false;
+  if (!PointeeTy.isConstQualified())
+    return false;
+  if (PointeeTy->isAnyPointerType())
+    return false;
+  return true;
+}
+
+// Try to retrieve the function declaration and find the function parameter
+// types which are pointers/references to a non-pointer const.
+// We do not invalidate the corresponding argument regions.
+static void findPtrToConstParams(llvm::SmallSet<unsigned, 1> &PreserveArgs,
+                                 const CallEvent &Call) {
+  const Decl *CallDecl = Call.getDecl();
+  if (!CallDecl)
+    return;
+
+  if (Call.hasNonZeroCallbackArg())
+    return;
+
+  if (const FunctionDecl *FDecl = dyn_cast<FunctionDecl>(CallDecl)) {
+    const IdentifierInfo *II = FDecl->getIdentifier();
+
+    // List the cases, where the region should be invalidated even if the
+    // argument is const.
+    // FIXME: This is conflating invalidating /contents/ and invalidating
+    // /metadata/. Now that we pass the CallEvent to the checkers, they
+    // should probably be doing this work themselves.
+    if (II) {
+      StringRef FName = II->getName();
+      //  - 'int pthread_setspecific(ptheread_key k, const void *)' stores a
+      // value into thread local storage. The value can later be retrieved with
+      // 'void *ptheread_getspecific(pthread_key)'. So even thought the
+      // parameter is 'const void *', the region escapes through the call.
+      //  - funopen - sets a buffer for future IO calls.
+      //  - ObjC functions that end with "NoCopy" can free memory, of the passed
+      // in buffer.
+      // - Many CF containers allow objects to escape through custom
+      // allocators/deallocators upon container construction.
+      // - NSXXInsertXX, for example NSMapInsertIfAbsent, since they can
+      // be deallocated by NSMapRemove.
+      // - Any call that has a callback as one of the arguments.
+      if (FName == "pthread_setspecific" ||
+          FName == "funopen" ||
+          FName.endswith("NoCopy") ||
+          (FName.startswith("NS") &&
+           (FName.find("Insert") != StringRef::npos)) ||
+          CallOrObjCMessage::isCFCGAllowingEscape(FName))
+        return;
+    }
+  }
+
+  unsigned Idx = 0;
+  for (CallEvent::param_type_iterator I = Call.param_type_begin(),
+                                       E = Call.param_type_end();
+       I != E; ++I, ++Idx) {
+    if (isPointerToConst(*I))
+      PreserveArgs.insert(Idx);
+  }
+}
+
+ProgramStateRef CallEvent::invalidateRegions(unsigned BlockCount,
+                                              ProgramStateRef Orig) const {
+  ProgramStateRef Result = (Orig ? Orig : State);
+
+  SmallVector<const MemRegion *, 8> RegionsToInvalidate;
+  addExtraInvalidatedRegions(RegionsToInvalidate);
+
+  // Indexes of arguments whose values will be preserved by the call.
+  llvm::SmallSet<unsigned, 1> PreserveArgs;
+  findPtrToConstParams(PreserveArgs, *this);
+
+  for (unsigned Idx = 0, Count = getNumArgs(); Idx != Count; ++Idx) {
+    if (PreserveArgs.count(Idx))
+      continue;
+
+    SVal V = getArgSVal(Idx);
+
+    // If we are passing a location wrapped as an integer, unwrap it and
+    // invalidate the values referred by the location.
+    if (nonloc::LocAsInteger *Wrapped = dyn_cast<nonloc::LocAsInteger>(&V))
+      V = Wrapped->getLoc();
+    else if (!isa<Loc>(V))
+      continue;
+
+    if (const MemRegion *R = V.getAsRegion()) {
+      // Invalidate the value of the variable passed by reference.
+
+      // Are we dealing with an ElementRegion?  If the element type is
+      // a basic integer type (e.g., char, int) and the underlying region
+      // is a variable region then strip off the ElementRegion.
+      // FIXME: We really need to think about this for the general case
+      //   as sometimes we are reasoning about arrays and other times
+      //   about (char*), etc., is just a form of passing raw bytes.
+      //   e.g., void *p = alloca(); foo((char*)p);
+      if (const ElementRegion *ER = dyn_cast<ElementRegion>(R)) {
+        // Checking for 'integral type' is probably too promiscuous, but
+        // we'll leave it in for now until we have a systematic way of
+        // handling all of these cases.  Eventually we need to come up
+        // with an interface to StoreManager so that this logic can be
+        // appropriately delegated to the respective StoreManagers while
+        // still allowing us to do checker-specific logic (e.g.,
+        // invalidating reference counts), probably via callbacks.
+        if (ER->getElementType()->isIntegralOrEnumerationType()) {
+          const MemRegion *superReg = ER->getSuperRegion();
+          if (isa<VarRegion>(superReg) || isa<FieldRegion>(superReg) ||
+              isa<ObjCIvarRegion>(superReg))
+            R = cast<TypedRegion>(superReg);
+        }
+        // FIXME: What about layers of ElementRegions?
+      }
+
+      // Mark this region for invalidation.  We batch invalidate regions
+      // below for efficiency.
+      RegionsToInvalidate.push_back(R);
+    }
+  }
+
+  // Invalidate designated regions using the batch invalidation API.
+  // NOTE: Even if RegionsToInvalidate is empty, we may still invalidate
+  //  global variables.
+  return Result->invalidateRegions(RegionsToInvalidate, getOriginExpr(),
+                                   BlockCount, LCtx, /*Symbols=*/0, this);
+}
+
+CallEvent::param_iterator AnyFunctionCall::param_begin() const {
+  const FunctionDecl *D = getDecl();
+  if (!D)
+    return 0;
+
+  return D->param_begin();
+}
+
+CallEvent::param_iterator AnyFunctionCall::param_end() const {
+  const FunctionDecl *D = getDecl();
+  if (!D)
+    return 0;
+
+  return D->param_end();
+}
+
+QualType AnyFunctionCall::getDeclaredResultType() const {
+  const FunctionDecl *D = getDecl();
+  if (!D)
+    return QualType();
+
+  return D->getResultType();
+}
+
+const FunctionDecl *SimpleCall::getDecl() const {
+  const FunctionDecl *D = CE->getDirectCallee();
+  if (D)
+    return D;
+
+  return getSVal(CE->getCallee()).getAsFunctionDecl();
+}
+
+void CXXMemberCall::addExtraInvalidatedRegions(RegionList &Regions) const {
+  const Expr *Base = getOriginExpr()->getImplicitObjectArgument();
+
+  // FIXME: Will eventually need to cope with member pointers.  This is
+  // a limitation in getImplicitObjectArgument().
+  if (!Base)
+    return;
+    
+  if (const MemRegion *R = getSVal(Base).getAsRegion())
+    Regions.push_back(R);
+}
+
+const BlockDataRegion *BlockCall::getBlockRegion() const {
+  const Expr *Callee = getOriginExpr()->getCallee();
+  const MemRegion *DataReg = getSVal(Callee).getAsRegion();
+
+  return cast<BlockDataRegion>(DataReg);
+}
+
+CallEvent::param_iterator BlockCall::param_begin() const {
+  return getBlockRegion()->getDecl()->param_begin();
+}
+
+CallEvent::param_iterator BlockCall::param_end() const {
+  return getBlockRegion()->getDecl()->param_end();
+}
+
+void BlockCall::addExtraInvalidatedRegions(RegionList &Regions) const {
+  Regions.push_back(getBlockRegion());
+}
+
+QualType BlockCall::getDeclaredResultType() const {
+  QualType BlockTy = getBlockRegion()->getCodeRegion()->getLocationType();
+  return cast<FunctionType>(BlockTy->getPointeeType())->getResultType();
+}
+
+void CXXConstructorCall::addExtraInvalidatedRegions(RegionList &Regions) const {
+  if (Target)
+    Regions.push_back(Target);
+}
+
+CallEvent::param_iterator ObjCMessageInvocation::param_begin() const {
+  const ObjCMethodDecl *D = getDecl();
+  if (!D)
+    return 0;
+
+  return D->param_begin();
+}
+
+CallEvent::param_iterator ObjCMessageInvocation::param_end() const {
+  const ObjCMethodDecl *D = getDecl();
+  if (!D)
+    return 0;
+
+  return D->param_end();
+}
+
+void
+ObjCMessageInvocation::addExtraInvalidatedRegions(RegionList &Regions) const {
+  if (const MemRegion *R = getReceiverSVal().getAsRegion())
+    Regions.push_back(R);
+}
+
+QualType ObjCMessageInvocation::getDeclaredResultType() const {
+  const ObjCMethodDecl *D = getDecl();
+  if (!D)
+    return QualType();
+
+  return D->getResultType();
+}
+
+SVal ObjCMessageInvocation::getReceiverSVal() const {
+  // FIXME: Is this the best way to handle class receivers?
+  if (!isInstanceMessage())
+    return UnknownVal();
+    
+  const Expr *Base = Msg.getInstanceReceiver();
+  if (Base)
+    return getSVal(Base);
+
+  // An instance message with no expression means we are sending to super.
+  // In this case the object reference is the same as 'self'.
+  const ImplicitParamDecl *SelfDecl = LCtx->getSelfDecl();
+  assert(SelfDecl && "No message receiver Expr, but not in an ObjC method");
+  return loc::MemRegionVal(State->getRegion(SelfDecl, LCtx));
+}
diff --git a/lib/StaticAnalyzer/Core/CheckerManager.cpp b/lib/StaticAnalyzer/Core/CheckerManager.cpp
index 8a6ea1d0f8..b3d93cfe35 100644
--- a/lib/StaticAnalyzer/Core/CheckerManager.cpp
+++ b/lib/StaticAnalyzer/Core/CheckerManager.cpp
@@ -431,7 +431,7 @@ CheckerManager::runCheckersForRegionChanges(ProgramStateRef state,
                             const StoreManager::InvalidatedSymbols *invalidated,
                                     ArrayRef<const MemRegion *> ExplicitRegions,
                                           ArrayRef<const MemRegion *> Regions,
-                                          const CallOrObjCMessage *Call) {
+                                          const CallEvent *Call) {
   for (unsigned i = 0, e = RegionChangesCheckers.size(); i != e; ++i) {
     // If any checker declares the state infeasible (or if it starts that way),
     // bail out.
diff --git a/lib/StaticAnalyzer/Core/ExprEngine.cpp b/lib/StaticAnalyzer/Core/ExprEngine.cpp
index a206a1a2fb..74c65c8be0 100644
--- a/lib/StaticAnalyzer/Core/ExprEngine.cpp
+++ b/lib/StaticAnalyzer/Core/ExprEngine.cpp
@@ -185,7 +185,7 @@ ExprEngine::processRegionChanges(ProgramStateRef state,
                             const StoreManager::InvalidatedSymbols *invalidated,
                                  ArrayRef<const MemRegion *> Explicits,