[analyzer] Move the files in lib/StaticAnalyzer to lib/StaticAnalyzer/Core.

Eventually there will also be a lib/StaticAnalyzer/Frontend that will handle initialization and checker registration.
Yet another library to avoid cyclic dependencies between Core and Checkers.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@125124 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 0 insertions, 917 deletions

diff --git a/lib/StaticAnalyzer/SimpleSValBuilder.cpp b/lib/StaticAnalyzer/SimpleSValBuilder.cpp
deleted file mode 100644
index 6c65da4635..0000000000
--- a/lib/StaticAnalyzer/SimpleSValBuilder.cpp
+++ /dev/null
@@ -1,917 +0,0 @@
-// SimpleSValBuilder.cpp - A basic SValBuilder -----------------------*- C++ -*-
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-//  This file defines SimpleSValBuilder, a basic implementation of SValBuilder.
-//
-//===----------------------------------------------------------------------===//
-
-#include "clang/StaticAnalyzer/PathSensitive/SValBuilder.h"
-#include "clang/StaticAnalyzer/PathSensitive/GRState.h"
-
-using namespace clang;
-using namespace ento;
-
-namespace {
-class SimpleSValBuilder : public SValBuilder {
-protected:
-  virtual SVal evalCastNL(NonLoc val, QualType castTy);
-  virtual SVal evalCastL(Loc val, QualType castTy);
-
-public:
-  SimpleSValBuilder(llvm::BumpPtrAllocator &alloc, ASTContext &context,
-                    GRStateManager &stateMgr)
-                    : SValBuilder(alloc, context, stateMgr) {}
-  virtual ~SimpleSValBuilder() {}
-
-  virtual SVal evalMinus(NonLoc val);
-  virtual SVal evalComplement(NonLoc val);
-  virtual SVal evalBinOpNN(const GRState *state, BinaryOperator::Opcode op,
-                           NonLoc lhs, NonLoc rhs, QualType resultTy);
-  virtual SVal evalBinOpLL(const GRState *state, BinaryOperator::Opcode op,
-                           Loc lhs, Loc rhs, QualType resultTy);
-  virtual SVal evalBinOpLN(const GRState *state, BinaryOperator::Opcode op,
-                           Loc lhs, NonLoc rhs, QualType resultTy);
-
-  /// getKnownValue - evaluates a given SVal. If the SVal has only one possible
-  ///  (integer) value, that value is returned. Otherwise, returns NULL.
-  virtual const llvm::APSInt *getKnownValue(const GRState *state, SVal V);
-  
-  SVal MakeSymIntVal(const SymExpr *LHS, BinaryOperator::Opcode op,
-                     const llvm::APSInt &RHS, QualType resultTy);
-};
-} // end anonymous namespace
-
-SValBuilder *ento::createSimpleSValBuilder(llvm::BumpPtrAllocator &alloc,
-                                           ASTContext &context,
-                                           GRStateManager &stateMgr) {
-  return new SimpleSValBuilder(alloc, context, stateMgr);
-}
-
-//===----------------------------------------------------------------------===//
-// Transfer function for Casts.
-//===----------------------------------------------------------------------===//
-
-SVal SimpleSValBuilder::evalCastNL(NonLoc val, QualType castTy) {
-
-  bool isLocType = Loc::IsLocType(castTy);
-
-  if (nonloc::LocAsInteger *LI = dyn_cast<nonloc::LocAsInteger>(&val)) {
-    if (isLocType)
-      return LI->getLoc();
-
-    // FIXME: Correctly support promotions/truncations.
-    unsigned castSize = Context.getTypeSize(castTy);
-    if (castSize == LI->getNumBits())
-      return val;
-    return makeLocAsInteger(LI->getLoc(), castSize);
-  }
-
-  if (const SymExpr *se = val.getAsSymbolicExpression()) {
-    QualType T = Context.getCanonicalType(se->getType(Context));
-    if (T == Context.getCanonicalType(castTy))
-      return val;
-    
-    // FIXME: Remove this hack when we support symbolic truncation/extension.
-    // HACK: If both castTy and T are integers, ignore the cast.  This is
-    // not a permanent solution.  Eventually we want to precisely handle
-    // extension/truncation of symbolic integers.  This prevents us from losing
-    // precision when we assign 'x = y' and 'y' is symbolic and x and y are
-    // different integer types.
-    if (T->isIntegerType() && castTy->isIntegerType())
-      return val;
-
-    return UnknownVal();
-  }
-
-  if (!isa<nonloc::ConcreteInt>(val))
-    return UnknownVal();
-
-  // Only handle casts from integers to integers.
-  if (!isLocType && !castTy->isIntegerType())
-    return UnknownVal();
-
-  llvm::APSInt i = cast<nonloc::ConcreteInt>(val).getValue();
-  i.setIsUnsigned(castTy->isUnsignedIntegerType() || Loc::IsLocType(castTy));
-  i = i.extOrTrunc(Context.getTypeSize(castTy));
-
-  if (isLocType)
-    return makeIntLocVal(i);
-  else
-    return makeIntVal(i);
-}
-
-SVal SimpleSValBuilder::evalCastL(Loc val, QualType castTy) {
-
-  // Casts from pointers -> pointers, just return the lval.
-  //
-  // Casts from pointers -> references, just return the lval.  These
-  //   can be introduced by the frontend for corner cases, e.g
-  //   casting from va_list* to __builtin_va_list&.
-  //
-  if (Loc::IsLocType(castTy) || castTy->isReferenceType())
-    return val;
-
-  // FIXME: Handle transparent unions where a value can be "transparently"
-  //  lifted into a union type.
-  if (castTy->isUnionType())
-    return UnknownVal();
-
-  if (castTy->isIntegerType()) {
-    unsigned BitWidth = Context.getTypeSize(castTy);
-
-    if (!isa<loc::ConcreteInt>(val))
-      return makeLocAsInteger(val, BitWidth);
-
-    llvm::APSInt i = cast<loc::ConcreteInt>(val).getValue();
-    i.setIsUnsigned(castTy->isUnsignedIntegerType() || Loc::IsLocType(castTy));
-    i = i.extOrTrunc(BitWidth);
-    return makeIntVal(i);
-  }
-
-  // All other cases: return 'UnknownVal'.  This includes casting pointers
-  // to floats, which is probably badness it itself, but this is a good
-  // intermediate solution until we do something better.
-  return UnknownVal();
-}
-
-//===----------------------------------------------------------------------===//
-// Transfer function for unary operators.
-//===----------------------------------------------------------------------===//
-
-SVal SimpleSValBuilder::evalMinus(NonLoc val) {
-  switch (val.getSubKind()) {
-  case nonloc::ConcreteIntKind:
-    return cast<nonloc::ConcreteInt>(val).evalMinus(*this);
-  default:
-    return UnknownVal();
-  }
-}
-
-SVal SimpleSValBuilder::evalComplement(NonLoc X) {
-  switch (X.getSubKind()) {
-  case nonloc::ConcreteIntKind:
-    return cast<nonloc::ConcreteInt>(X).evalComplement(*this);
-  default:
-    return UnknownVal();
-  }
-}
-
-//===----------------------------------------------------------------------===//
-// Transfer function for binary operators.
-//===----------------------------------------------------------------------===//
-
-static BinaryOperator::Opcode NegateComparison(BinaryOperator::Opcode op) {
-  switch (op) {
-  default:
-    assert(false && "Invalid opcode.");
-  case BO_LT: return BO_GE;
-  case BO_GT: return BO_LE;
-  case BO_LE: return BO_GT;
-  case BO_GE: return BO_LT;
-  case BO_EQ: return BO_NE;
-  case BO_NE: return BO_EQ;
-  }
-}
-
-static BinaryOperator::Opcode ReverseComparison(BinaryOperator::Opcode op) {
-  switch (op) {
-  default:
-    assert(false && "Invalid opcode.");
-  case BO_LT: return BO_GT;
-  case BO_GT: return BO_LT;
-  case BO_LE: return BO_GE;
-  case BO_GE: return BO_LE;
-  case BO_EQ:
-  case BO_NE:
-    return op;
-  }
-}
-
-SVal SimpleSValBuilder::MakeSymIntVal(const SymExpr *LHS,
-                                    BinaryOperator::Opcode op,
-                                    const llvm::APSInt &RHS,
-                                    QualType resultTy) {
-  bool isIdempotent = false;
-
-  // Check for a few special cases with known reductions first.
-  switch (op) {
-  default:
-    // We can't reduce this case; just treat it normally.
-    break;
-  case BO_Mul:
-    // a*0 and a*1
-    if (RHS == 0)
-      return makeIntVal(0, resultTy);
-    else if (RHS == 1)
-      isIdempotent = true;
-    break;
-  case BO_Div:
-    // a/0 and a/1
-    if (RHS == 0)
-      // This is also handled elsewhere.
-      return UndefinedVal();
-    else if (RHS == 1)
-      isIdempotent = true;
-    break;
-  case BO_Rem:
-    // a%0 and a%1
-    if (RHS == 0)
-      // This is also handled elsewhere.
-      return UndefinedVal();
-    else if (RHS == 1)
-      return makeIntVal(0, resultTy);
-    break;
-  case BO_Add:
-  case BO_Sub:
-  case BO_Shl:
-  case BO_Shr:
-  case BO_Xor:
-    // a+0, a-0, a<<0, a>>0, a^0
-    if (RHS == 0)
-      isIdempotent = true;
-    break;
-  case BO_And:
-    // a&0 and a&(~0)
-    if (RHS == 0)
-      return makeIntVal(0, resultTy);
-    else if (RHS.isAllOnesValue())
-      isIdempotent = true;
-    break;
-  case BO_Or:
-    // a|0 and a|(~0)
-    if (RHS == 0)
-      isIdempotent = true;
-    else if (RHS.isAllOnesValue()) {
-      const llvm::APSInt &Result = BasicVals.Convert(resultTy, RHS);
-      return nonloc::ConcreteInt(Result);
-    }
-    break;
-  }
-
-  // Idempotent ops (like a*1) can still change the type of an expression.
-  // Wrap the LHS up in a NonLoc again and let evalCastNL do the dirty work.
-  if (isIdempotent) {
-    if (SymbolRef LHSSym = dyn_cast<SymbolData>(LHS))
-      return evalCastNL(nonloc::SymbolVal(LHSSym), resultTy);
-    return evalCastNL(nonloc::SymExprVal(LHS), resultTy);
-  }
-
-  // If we reach this point, the expression cannot be simplified.
-  // Make a SymExprVal for the entire thing.
-  return makeNonLoc(LHS, op, RHS, resultTy);
-}
-
-SVal SimpleSValBuilder::evalBinOpNN(const GRState *state,
-                                  BinaryOperator::Opcode op,
-                                  NonLoc lhs, NonLoc rhs,
-                                  QualType resultTy)  {
-  // Handle trivial case where left-side and right-side are the same.
-  if (lhs == rhs)
-    switch (op) {
-      default:
-        break;
-      case BO_EQ:
-      case BO_LE:
-      case BO_GE:
-        return makeTruthVal(true, resultTy);
-      case BO_LT:
-      case BO_GT:
-      case BO_NE:
-        return makeTruthVal(false, resultTy);
-      case BO_Xor:
-      case BO_Sub:
-        return makeIntVal(0, resultTy);
-      case BO_Or:
-      case BO_And:
-        return evalCastNL(lhs, resultTy);
-    }
-
-  while (1) {
-    switch (lhs.getSubKind()) {
-    default:
-      return UnknownVal();
-    case nonloc::LocAsIntegerKind: {
-      Loc lhsL = cast<nonloc::LocAsInteger>(lhs).getLoc();
-      switch (rhs.getSubKind()) {
-        case nonloc::LocAsIntegerKind:
-          return evalBinOpLL(state, op, lhsL,
-                             cast<nonloc::LocAsInteger>(rhs).getLoc(),
-                             resultTy);
-        case nonloc::ConcreteIntKind: {
-          // Transform the integer into a location and compare.
-          llvm::APSInt i = cast<nonloc::ConcreteInt>(rhs).getValue();
-          i.setIsUnsigned(true);
-          i = i.extOrTrunc(Context.getTypeSize(Context.VoidPtrTy));
-          return evalBinOpLL(state, op, lhsL, makeLoc(i), resultTy);
-        }
-        default:
-          switch (op) {
-            case BO_EQ:
-              return makeTruthVal(false, resultTy);
-            case BO_NE:
-              return makeTruthVal(true, resultTy);
-            default:
-              // This case also handles pointer arithmetic.
-              return UnknownVal();
-          }
-      }
-    }
-    case nonloc::SymExprValKind: {
-      nonloc::SymExprVal *selhs = cast<nonloc::SymExprVal>(&lhs);
-
-      // Only handle LHS of the form "$sym op constant", at least for now.
-      const SymIntExpr *symIntExpr =
-        dyn_cast<SymIntExpr>(selhs->getSymbolicExpression());
-
-      if (!symIntExpr)
-        return UnknownVal();
-
-      // Is this a logical not? (!x is represented as x == 0.)
-      if (op == BO_EQ && rhs.isZeroConstant()) {
-        // We know how to negate certain expressions. Simplify them here.
-
-        BinaryOperator::Opcode opc = symIntExpr->getOpcode();
-        switch (opc) {
-        default:
-          // We don't know how to negate this operation.
-          // Just handle it as if it were a normal comparison to 0.
-          break;
-        case BO_LAnd:
-        case BO_LOr:
-          assert(false && "Logical operators handled by branching logic.");
-          return UnknownVal();
-        case BO_Assign:
-        case BO_MulAssign:
-        case BO_DivAssign:
-        case BO_RemAssign:
-        case BO_AddAssign:
-        case BO_SubAssign:
-        case BO_ShlAssign:
-        case BO_ShrAssign:
-        case BO_AndAssign:
-        case BO_XorAssign:
-        case BO_OrAssign:
-        case BO_Comma:
-          assert(false && "'=' and ',' operators handled by ExprEngine.");
-          return UnknownVal();
-        case BO_PtrMemD:
-        case BO_PtrMemI:
-          assert(false && "Pointer arithmetic not handled here.");
-          return UnknownVal();
-        case BO_LT:
-        case BO_GT:
-        case BO_LE:
-        case BO_GE:
-        case BO_EQ:
-        case BO_NE:
-          // Negate the comparison and make a value.
-          opc = NegateComparison(opc);
-          assert(symIntExpr->getType(Context) == resultTy);
-          return makeNonLoc(symIntExpr->getLHS(), opc,
-                                   symIntExpr->getRHS(), resultTy);
-        }
-      }
-
-      // For now, only handle expressions whose RHS is a constant.
-      const nonloc::ConcreteInt *rhsInt = dyn_cast<nonloc::ConcreteInt>(&rhs);
-      if (!rhsInt)
-        return UnknownVal();
-
-      // If both the LHS and the current expression are additive,
-      // fold their constants.
-      if (BinaryOperator::isAdditiveOp(op)) {
-        BinaryOperator::Opcode lop = symIntExpr->getOpcode();
-        if (BinaryOperator::isAdditiveOp(lop)) {
-          // resultTy may not be the best type to convert to, but it's
-          // probably the best choice in expressions with mixed type
-          // (such as x+1U+2LL). The rules for implicit conversions should
-          // choose a reasonable type to preserve the expression, and will
-          // at least match how the value is going to be used.
-          const llvm::APSInt &first =
-            BasicVals.Convert(resultTy, symIntExpr->getRHS());
-          const llvm::APSInt &second =
-            BasicVals.Convert(resultTy, rhsInt->getValue());
-          const llvm::APSInt *newRHS;
-          if (lop == op)
-            newRHS = BasicVals.evalAPSInt(BO_Add, first, second);
-          else
-            newRHS = BasicVals.evalAPSInt(BO_Sub, first, second);
-          return MakeSymIntVal(symIntExpr->getLHS(), lop, *newRHS, resultTy);
-        }
-      }
-
-      // Otherwise, make a SymExprVal out of the expression.
-      return MakeSymIntVal(symIntExpr, op, rhsInt->getValue(), resultTy);
-    }
-    case nonloc::ConcreteIntKind: {
-      const nonloc::ConcreteInt& lhsInt = cast<nonloc::ConcreteInt>(lhs);
-
-      if (isa<nonloc::ConcreteInt>(rhs)) {
-        return lhsInt.evalBinOp(*this, op, cast<nonloc::ConcreteInt>(rhs));
-      } else {
-        const llvm::APSInt& lhsValue = lhsInt.getValue();
-        
-        // Swap the left and right sides and flip the operator if doing so
-        // allows us to better reason about the expression (this is a form
-        // of expression canonicalization).
-        // While we're at it, catch some special cases for non-commutative ops.
-        NonLoc tmp = rhs;
-        rhs = lhs;
-        lhs = tmp;
-
-        switch (op) {
-          case BO_LT:
-          case BO_GT:
-          case BO_LE:
-          case BO_GE:
-            op = ReverseComparison(op);
-            continue;
-          case BO_EQ:
-          case BO_NE:
-          case BO_Add:
-          case BO_Mul:
-          case BO_And:
-          case BO_Xor:
-          case BO_Or:
-            continue;
-          case BO_Shr:
-            if (lhsValue.isAllOnesValue() && lhsValue.isSigned())
-              // At this point lhs and rhs have been swapped.
-              return rhs;
-            // FALL-THROUGH
-          case BO_Shl:
-            if (lhsValue == 0)
-              // At this point lhs and rhs have been swapped.
-              return rhs;
-            return UnknownVal();
-          default:
-            return UnknownVal();
-        }
-      }
-    }
-    case nonloc::SymbolValKind: {
-      nonloc::SymbolVal *slhs = cast<nonloc::SymbolVal>(&lhs);
-      SymbolRef Sym = slhs->getSymbol();
-      // Does the symbol simplify to a constant?  If so, "fold" the constant
-      // by setting 'lhs' to a ConcreteInt and try again.
-      if (Sym->getType(Context)->isIntegerType())
-        if (const llvm::APSInt *Constant = state->getSymVal(Sym)) {
-          // The symbol evaluates to a constant. If necessary, promote the
-          // folded constant (LHS) to the result type.
-          const llvm::APSInt &lhs_I = BasicVals.Convert(resultTy, *Constant);
-          lhs = nonloc::ConcreteInt(lhs_I);
-          
-          // Also promote the RHS (if necessary).
-
-          // For shifts, it is not necessary to promote the RHS.
-          if (BinaryOperator::isShiftOp(op))
-            continue;
-          
-          // Other operators: do an implicit conversion.  This shouldn't be
-          // necessary once we support truncation/extension of symbolic values.
-          if (nonloc::ConcreteInt *rhs_I = dyn_cast<nonloc::ConcreteInt>(&rhs)){
-            rhs = nonloc::ConcreteInt(BasicVals.Convert(resultTy,
-                                                        rhs_I->getValue()));
-          }
-          
-          continue;
-        }
-
-      // Is the RHS a symbol we can simplify?
-      if (const nonloc::SymbolVal *srhs = dyn_cast<nonloc::SymbolVal>(&rhs)) {
-        SymbolRef RSym = srhs->getSymbol();
-        if (RSym->getType(Context)->isIntegerType()) {
-          if (const llvm::APSInt *Constant = state->getSymVal(RSym)) {
-            // The symbol evaluates to a constant.
-            const llvm::APSInt &rhs_I = BasicVals.Convert(resultTy, *Constant);
-            rhs = nonloc::ConcreteInt(rhs_I);
-          }
-        }
-      }
-
-      if (isa<nonloc::ConcreteInt>(rhs)) {
-        return MakeSymIntVal(slhs->getSymbol(), op,
-                             cast<nonloc::ConcreteInt>(rhs).getValue(),
-                             resultTy);
-      }
-
-      return UnknownVal();
-    }
-    }
-  }
-}
-
-// FIXME: all this logic will change if/when we have MemRegion::getLocation().
-SVal SimpleSValBuilder::evalBinOpLL(const GRState *state,
-                                  BinaryOperator::Opcode op,
-                                  Loc lhs, Loc rhs,
-                                  QualType resultTy) {
-  // Only comparisons and subtractions are valid operations on two pointers.
-  // See [C99 6.5.5 through 6.5.14] or [C++0x 5.6 through 5.15].
-  // However, if a pointer is casted to an integer, evalBinOpNN may end up
-  // calling this function with another operation (PR7527). We don't attempt to
-  // model this for now, but it could be useful, particularly when the
-  // "location" is actually an integer value that's been passed through a void*.
-  if (!(BinaryOperator::isComparisonOp(op) || op == BO_Sub))
-    return UnknownVal();
-
-  // Special cases for when both sides are identical.
-  if (lhs == rhs) {
-    switch (op) {
-    default:
-      assert(false && "Unimplemented operation for two identical values");
-      return UnknownVal();
-    case BO_Sub:
-      return makeZeroVal(resultTy);
-    case BO_EQ:
-    case BO_LE:
-    case BO_GE:
-      return makeTruthVal(true, resultTy);
-    case BO_NE:
-    case BO_LT:
-    case BO_GT:
-      return makeTruthVal(false, resultTy);
-    }
-  }
-
-  switch (lhs.getSubKind()) {
-  default:
-    assert(false && "Ordering not implemented for this Loc.");
-    return UnknownVal();
-
-  case loc::GotoLabelKind:
-    // The only thing we know about labels is that they're non-null.
-    if (rhs.isZeroConstant()) {
-      switch (op) {
-      default:
-        break;
-      case BO_Sub:
-        return evalCastL(lhs, resultTy);
-      case BO_EQ:
-      case BO_LE:
-      case BO_LT:
-        return makeTruthVal(false, resultTy);
-      case BO_NE:
-      case BO_GT:
-      case BO_GE:
-        return makeTruthVal(true, resultTy);
-      }
-    }
-    // There may be two labels for the same location, and a function region may
-    // have the same address as a label at the start of the function (depending
-    // on the ABI).
-    // FIXME: we can probably do a comparison against other MemRegions, though.
-    // FIXME: is there a way to tell if two labels refer to the same location?
-    return UnknownVal(); 
-
-  case loc::ConcreteIntKind: {
-    // If one of the operands is a symbol and the other is a constant,
-    // build an expression for use by the constraint manager.
-    if (SymbolRef rSym = rhs.getAsLocSymbol()) {
-      // We can only build expressions with symbols on the left,
-      // so we need a reversible operator.
-      if (!BinaryOperator::isComparisonOp(op))
-        return UnknownVal();
-
-      const llvm::APSInt &lVal = cast<loc::ConcreteInt>(lhs).getValue();
-      return makeNonLoc(rSym, ReverseComparison(op), lVal, resultTy);
-    }
-
-    // If both operands are constants, just perform the operation.
-    if (loc::ConcreteInt *rInt = dyn_cast<loc::ConcreteInt>(&rhs)) {
-      SVal ResultVal = cast<loc::ConcreteInt>(lhs).evalBinOp(BasicVals, op,
-                                                             *rInt);
-      if (Loc *Result = dyn_cast<Loc>(&ResultVal))
-        return evalCastL(*Result, resultTy);
-      else
-        return UnknownVal();
-    }
-
-    // Special case comparisons against NULL.
-    // This must come after the test if the RHS is a symbol, which is used to
-    // build constraints. The address of any non-symbolic region is guaranteed
-    // to be non-NULL, as is any label.
-    assert(isa<loc::MemRegionVal>(rhs) || isa<loc::GotoLabel>(rhs));
-    if (lhs.isZeroConstant()) {
-      switch (op) {
-      default:
-        break;
-      case BO_EQ:
-      case BO_GT:
-      case BO_GE:
-        return makeTruthVal(false, resultTy);
-      case BO_NE:
-      case BO_LT:
-      case BO_LE:
-        return makeTruthVal(true, resultTy);
-      }
-    }
-
-    // Comparing an arbitrary integer to a region or label address is
-    // completely unknowable.
-    return UnknownVal();
-  }
-  case loc::MemRegionKind: {
-    if (loc::ConcreteInt *rInt = dyn_cast<loc::ConcreteInt>(&rhs)) {
-      // If one of the operands is a symbol and the other is a constant,
-      // build an expression for use by the constraint manager.
-      if (SymbolRef lSym = lhs.getAsLocSymbol())
-        return MakeSymIntVal(lSym, op, rInt->getValue(), resultTy);
-
-      // Special case comparisons to NULL.
-      // This must come after the test if the LHS is a symbol, which is used to
-      // build constraints. The address of any non-symbolic region is guaranteed
-      // to be non-NULL.
-      if (rInt->isZeroConstant()) {
-        switch (op) {
-        default:
-          break;
-        case BO_Sub:
-          return evalCastL(lhs, resultTy);
-        case BO_EQ:
-        case BO_LT:
-        case BO_LE:
-          return makeTruthVal(false, resultTy);
-        case BO_NE:
-        case BO_GT:
-        case BO_GE:
-          return makeTruthVal(true, resultTy);
-        }
-      }
-
-      // Comparing a region to an arbitrary integer is completely unknowable.
-      return UnknownVal();
-    }
-
-    // Get both values as regions, if possible.
-    const MemRegion *LeftMR = lhs.getAsRegion();
-    assert(LeftMR && "MemRegionKind SVal doesn't have a region!");
-
-    const MemRegion *RightMR = rhs.getAsRegion();
-    if (!RightMR)
-      // The RHS is probably a label, which in theory could address a region.
-      // FIXME: we can probably make a more useful statement about non-code
-      // regions, though.
-      return UnknownVal();
-
-    // If both values wrap regions, see if they're from different base regions.
-    const MemRegion *LeftBase = LeftMR->getBaseRegion();
-    const MemRegion *RightBase = RightMR->getBaseRegion();
-    if (LeftBase != RightBase &&
-        !isa<SymbolicRegion>(LeftBase) && !isa<SymbolicRegion>(RightBase)) {
-      switch (op) {
-      default:
-        return UnknownVal();
-      case BO_EQ:
-        return makeTruthVal(false, resultTy);
-      case BO_NE:
-        return makeTruthVal(true, resultTy);
-      }
-    }
-
-    // The two regions are from the same base region. See if they're both a
-    // type of region we know how to compare.
-
-    // FIXME: If/when there is a getAsRawOffset() for FieldRegions, this
-    // ElementRegion path and the FieldRegion path below should be unified.
-    if (const ElementRegion *LeftER = dyn_cast<ElementRegion>(LeftMR)) {
-      // First see if the right region is also an ElementRegion.
-      const ElementRegion *RightER = dyn_cast<ElementRegion>(RightMR);
-      if (!RightER)
-        return UnknownVal();
-
-      // Next, see if the two ERs have the same super-region and matching types.
-      // FIXME: This should do something useful even if the types don't match,
-      // though if both indexes are constant the RegionRawOffset path will
-      // give the correct answer.
-      if (LeftER->getSuperRegion() == RightER->getSuperRegion() &&
-          LeftER->getElementType() == RightER->getElementType()) {
-        // Get the left index and cast it to the correct type.
-        // If the index is unknown or undefined, bail out here.
-        SVal LeftIndexVal = LeftER->getIndex();
-        NonLoc *LeftIndex = dyn_cast<NonLoc>(&LeftIndexVal);
-        if (!LeftIndex)
-          return UnknownVal();
-        LeftIndexVal = evalCastNL(*LeftIndex, resultTy);
-        LeftIndex = dyn_cast<NonLoc>(&LeftIndexVal);
-        if (!LeftIndex)
-          return UnknownVal();
-
-        // Do the same for the right index.
-        SVal RightIndexVal = RightER->getIndex();
-        NonLoc *RightIndex = dyn_cast<NonLoc>(&RightIndexVal);
-        if (!RightIndex)
-          return UnknownVal();
-        RightIndexVal = evalCastNL(*RightIndex, resultTy);
-        RightIndex = dyn_cast<NonLoc>(&RightIndexVal);
-        if (!RightIndex)
-          return UnknownVal();
-
-        // Actually perform the operation.
-        // evalBinOpNN expects the two indexes to already be the right type.
-        return evalBinOpNN(state, op, *LeftIndex, *RightIndex, resultTy);
-      }
-
-      // If the element indexes aren't comparable, see if the raw offsets are.
-      RegionRawOffset LeftOffset = LeftER->getAsArrayOffset();
-      RegionRawOffset RightOffset = RightER->getAsArrayOffset();
-
-      if (LeftOffset.getRegion() != NULL &&
-          LeftOffset.getRegion() == RightOffset.getRegion()) {
-        CharUnits left = LeftOffset.getOffset();
-        CharUnits right = RightOffset.getOffset();
-
-        switch (op) {
-        default:
-          return UnknownVal();
-        case BO_LT:
-          return makeTruthVal(left < right, resultTy);
-        case BO_GT:
-          return makeTruthVal(left > right, resultTy);
-        case BO_LE:
-          return makeTruthVal(left <= right, resultTy);
-        case BO_GE:
-          return makeTruthVal(left >= right, resultTy);
-        case BO_EQ:
-          return makeTruthVal(left == right, resultTy);
-        case BO_NE:
-          return makeTruthVal(left != right, resultTy);
-        }
-      }
-
-      // If we get here, we have no way of comparing the ElementRegions.
-      return UnknownVal();
-    }
-
-    // See if both regions are fields of the same structure.
-    // FIXME: This doesn't handle nesting, inheritance, or Objective-C ivars.
-    if (const FieldRegion *LeftFR = dyn_cast<FieldRegion>(LeftMR)) {
-      // Only comparisons are meaningful here!
-      if (!BinaryOperator::isComparisonOp(op))
-        return UnknownVal();
-
-      // First see if the right region is also a FieldRegion.
-      const FieldRegion *RightFR = dyn_cast<FieldRegion>(RightMR);
-      if (!RightFR)
-        return UnknownVal();
-
-      // Next, see if the two FRs have the same super-region.
-      // FIXME: This doesn't handle casts yet, and simply stripping the casts
-      // doesn't help.
-      if (LeftFR->getSuperRegion() != RightFR->getSuperRegion())
-        return UnknownVal();
-
-      const FieldDecl *LeftFD = LeftFR->getDecl();
-      const FieldDecl *RightFD = RightFR->getDecl();
-      const RecordDecl *RD = LeftFD->getParent();
-
-      // Make sure the two FRs are from the same kind of record. Just in case!
-      // FIXME: This is probably where inheritance would be a problem.
-      if (RD != RightFD->getParent())
-        return UnknownVal();
-
-      // We know for sure that the two fields are not the same, since that
-      // would have given us the same SVal.
-      if (op == BO_EQ)
-        return makeTruthVal(false, resultTy);
-      if (op == BO_NE)
-        return makeTruthVal(true, resultTy);
-
-      // Iterate through the fields and see which one comes first.
-      // [C99 6.7.2.1.13] "Within a structure object, the non-bit-field
-      // members and the units in which bit-fields reside have addresses that
-      // increase in the order in which they are declared."
-      bool leftFirst = (op == BO_LT || op == BO_LE);
-      for (RecordDecl::field_iterator I = RD->field_begin(),
-           E = RD->field_end(); I!=E; ++I) {
-        if (*I == LeftFD)
-          return makeTruthVal(leftFirst, resultTy);
-        if (*I == RightFD)
-          return makeTruthVal(!leftFirst, resultTy);
-      }
-
-      assert(false && "Fields not found in parent record's definition");
-    }
-
-    // If we get here, we have no way of comparing the regions.
-    return UnknownVal();
-  }
-  }
-}
-
-SVal SimpleSValBuilder::evalBinOpLN(const GRState *state,
-                                  BinaryOperator::Opcode op,
-                                  Loc lhs, NonLoc rhs, QualType resultTy) {
-  
-  // Special case: rhs is a zero constant.
-  if (rhs.isZeroConstant())
-    return lhs;
-  
-  // Special case: 'rhs' is an integer that has the same width as a pointer and
-  // we are using the integer location in a comparison.  Normally this cannot be
-  // triggered, but transfer functions like those for OSCommpareAndSwapBarrier32
-  // can generate comparisons that trigger this code.
-  // FIXME: Are all locations guaranteed to have pointer width?
-  if (BinaryOperator::isComparisonOp(op)) {
-    if (nonloc::ConcreteInt *rhsInt = dyn_cast<nonloc::ConcreteInt>(&rhs)) {
-      const llvm::APSInt *x = &rhsInt->getValue();
-      ASTContext &ctx = Context;
-      if (ctx.getTypeSize(ctx.VoidPtrTy) == x->getBitWidth()) {
-        // Convert the signedness of the integer (if necessary).
-        if (x->isSigned())
-          x = &getBasicValueFactory().getValue(*x, true);
-
-        return evalBinOpLL(state, op, lhs, loc::ConcreteInt(*x), resultTy);
-      }
-    }
-  }
-  
-  // We are dealing with pointer arithmetic.
-
-  // Handle pointer arithmetic on constant values.
-  if (nonloc::ConcreteInt *rhsInt = dyn_cast<nonloc::ConcreteInt>(&rhs)) {
-    if (loc::ConcreteInt *lhsInt = dyn_cast<loc::ConcreteInt>(&lhs)) {
-      const llvm::APSInt &leftI = lhsInt->getValue();
-      assert(leftI.isUnsigned());
-      llvm::APSInt rightI(rhsInt->getValue(), /* isUnsigned */ true);
-
-      // Convert the bitwidth of rightI.  This should deal with overflow
-      // since we are dealing with concrete values.
-      rightI = rightI.extOrTrunc(leftI.getBitWidth());
-
-      // Offset the increment by the pointer size.
-      llvm::APSInt Multiplicand(rightI.getBitWidth(), /* isUnsigned */ true);
-      rightI *= Multiplicand;
-      
-      // Compute the adjusted pointer.
-      switch (op) {
-        case BO_Add:
-          rightI = leftI + rightI;
-          break;
-        case BO_Sub:
-          rightI = leftI - rightI;
-          break;
-        default:
-          llvm_unreachable("Invalid pointer arithmetic operation");
-      }
-      return loc::ConcreteInt(getBasicValueFactory().getValue(rightI));
-    }
-  }
-
-  // Handle cases where 'lhs' is a region.
-  if (const MemRegion *region = lhs.getAsRegion()) {
-    rhs = cast<NonLoc>(convertToArrayIndex(rhs));
-    SVal index = UnknownVal();
-    const MemRegion *superR = 0;
-    QualType elementType;
-
-    if (const ElementRegion *elemReg = dyn_cast<ElementRegion>(region)) {
-      index = evalBinOpNN(state, BO_Add, elemReg->getIndex(), rhs,
-                          getArrayIndexType());
-      superR = elemReg->getSuperRegion();
-      elementType = elemReg->getElementType();
-    }
-    else if (isa<SubRegion>(region)) {
-      superR = region;
-      index = rhs;
-      if (const PointerType *PT = resultTy->getAs<PointerType>()) {
-        elementType = PT->getPointeeType();
-      }
-      else {
-        const ObjCObjectPointerType *OT =
-          resultTy->getAs<ObjCObjectPointerType>();
-        elementType = OT->getPointeeType();
-      }
-    }
-
-    if (NonLoc *indexV = dyn_cast<NonLoc>(&index)) {
-      return loc::MemRegionVal(MemMgr.getElementRegion(elementType, *indexV,
-                                                       superR, getContext()));
-    }
-  }
-  return UnknownVal();  
-}
-
-const llvm::APSInt *SimpleSValBuilder::getKnownValue(const GRState *state,
-                                                   SVal V) {
-  if (V.isUnknownOrUndef())
-    return NULL;
-
-  if (loc::ConcreteInt* X = dyn_cast<loc::ConcreteInt>(&V))
-    return &X->getValue();
-
-  if (nonloc::ConcreteInt* X = dyn_cast<nonloc::ConcreteInt>(&V))
-    return &X->getValue();
-
-  if (SymbolRef Sym = V.getAsSymbol())
-    return state->getSymVal(Sym);
-
-  // FIXME: Add support for SymExprs.
-  return NULL;
-}