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diff --git a/lib/Analysis/SimpleSValuator.cpp b/lib/Analysis/SimpleSValuator.cpp
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-// SimpleSValuator.cpp - A basic SValuator ------------------------*- 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 SimpleSValuator, a basic implementation of SValuator.
-//
-//===----------------------------------------------------------------------===//
-
-#include "clang/Analysis/PathSensitive/SValuator.h"
-#include "clang/Analysis/PathSensitive/GRState.h"
-
-using namespace clang;
-
-namespace {
-class SimpleSValuator : public SValuator {
-protected:
- virtual SVal EvalCastNL(NonLoc val, QualType castTy);
- virtual SVal EvalCastL(Loc val, QualType castTy);
-
-public:
- SimpleSValuator(ValueManager &valMgr) : SValuator(valMgr) {}
- virtual ~SimpleSValuator() {}
-
- 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(BinaryOperator::Opcode op, Loc lhs, Loc rhs,
- QualType resultTy);
- virtual SVal EvalBinOpLN(const GRState *state, BinaryOperator::Opcode op,
- Loc lhs, NonLoc rhs, QualType resultTy);
-};
-} // end anonymous namespace
-
-SValuator *clang::CreateSimpleSValuator(ValueManager &valMgr) {
- return new SimpleSValuator(valMgr);
-}
-
-//===----------------------------------------------------------------------===//
-// Transfer function for Casts.
-//===----------------------------------------------------------------------===//
-
-SVal SimpleSValuator::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.
- ASTContext &Ctx = ValMgr.getContext();
- unsigned castSize = Ctx.getTypeSize(castTy);
- if (castSize == LI->getNumBits())
- return val;
-
- return ValMgr.makeLocAsInteger(LI->getLoc(), castSize);
- }
-
- if (const SymExpr *se = val.getAsSymbolicExpression()) {
- ASTContext &Ctx = ValMgr.getContext();
- QualType T = Ctx.getCanonicalType(se->getType(Ctx));
- if (T == Ctx.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.extOrTrunc(ValMgr.getContext().getTypeSize(castTy));
-
- if (isLocType)
- return ValMgr.makeIntLocVal(i);
- else
- return ValMgr.makeIntVal(i);
-}
-
-SVal SimpleSValuator::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();
-
- assert(castTy->isIntegerType());
- unsigned BitWidth = ValMgr.getContext().getTypeSize(castTy);
-
- if (!isa<loc::ConcreteInt>(val))
- return ValMgr.makeLocAsInteger(val, BitWidth);
-
- llvm::APSInt i = cast<loc::ConcreteInt>(val).getValue();
- i.setIsUnsigned(castTy->isUnsignedIntegerType() || Loc::IsLocType(castTy));
- i.extOrTrunc(BitWidth);
- return ValMgr.makeIntVal(i);
-}
-
-//===----------------------------------------------------------------------===//
-// Transfer function for unary operators.
-//===----------------------------------------------------------------------===//
-
-SVal SimpleSValuator::EvalMinus(NonLoc val) {
- switch (val.getSubKind()) {
- case nonloc::ConcreteIntKind:
- return cast<nonloc::ConcreteInt>(val).evalMinus(ValMgr);
- default:
- return UnknownVal();
- }
-}
-
-SVal SimpleSValuator::EvalComplement(NonLoc X) {
- switch (X.getSubKind()) {
- case nonloc::ConcreteIntKind:
- return cast<nonloc::ConcreteInt>(X).evalComplement(ValMgr);
- default:
- return UnknownVal();
- }
-}
-
-//===----------------------------------------------------------------------===//
-// Transfer function for binary operators.
-//===----------------------------------------------------------------------===//
-
-static BinaryOperator::Opcode NegateComparison(BinaryOperator::Opcode op) {
- switch (op) {
- default:
- assert(false && "Invalid opcode.");
- case BinaryOperator::LT: return BinaryOperator::GE;
- case BinaryOperator::GT: return BinaryOperator::LE;
- case BinaryOperator::LE: return BinaryOperator::GT;
- case BinaryOperator::GE: return BinaryOperator::LT;
- case BinaryOperator::EQ: return BinaryOperator::NE;
- case BinaryOperator::NE: return BinaryOperator::EQ;
- }
-}
-
-// Equality operators for Locs.
-// FIXME: All this logic will be revamped when we have MemRegion::getLocation()
-// implemented.
-
-static SVal EvalEquality(ValueManager &ValMgr, Loc lhs, Loc rhs, bool isEqual,
- QualType resultTy) {
-
- switch (lhs.getSubKind()) {
- default:
- assert(false && "EQ/NE not implemented for this Loc.");
- return UnknownVal();
-
- case loc::ConcreteIntKind: {
- if (SymbolRef rSym = rhs.getAsSymbol())
- return ValMgr.makeNonLoc(rSym,
- isEqual ? BinaryOperator::EQ
- : BinaryOperator::NE,
- cast<loc::ConcreteInt>(lhs).getValue(),
- resultTy);
- break;
- }
- case loc::MemRegionKind: {
- if (SymbolRef lSym = lhs.getAsLocSymbol()) {
- if (isa<loc::ConcreteInt>(rhs)) {
- return ValMgr.makeNonLoc(lSym,
- isEqual ? BinaryOperator::EQ
- : BinaryOperator::NE,
- cast<loc::ConcreteInt>(rhs).getValue(),
- resultTy);
- }
- }
- break;
- }
-
- case loc::GotoLabelKind:
- break;
- }
-
- return ValMgr.makeTruthVal(isEqual ? lhs == rhs : lhs != rhs, resultTy);
-}
-
-SVal SimpleSValuator::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 BinaryOperator::EQ:
- case BinaryOperator::LE:
- case BinaryOperator::GE:
- return ValMgr.makeTruthVal(true, resultTy);
- case BinaryOperator::LT:
- case BinaryOperator::GT:
- case BinaryOperator::NE:
- return ValMgr.makeTruthVal(false, 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(op, lhsL, cast<nonloc::LocAsInteger>(rhs).getLoc(),
- resultTy);
- case nonloc::ConcreteIntKind: {
- // Transform the integer into a location and compare.
- ASTContext& Ctx = ValMgr.getContext();
- llvm::APSInt i = cast<nonloc::ConcreteInt>(rhs).getValue();
- i.setIsUnsigned(true);
- i.extOrTrunc(Ctx.getTypeSize(Ctx.VoidPtrTy));
- return EvalBinOpLL(op, lhsL, ValMgr.makeLoc(i), resultTy);
- }
- default:
- switch (op) {
- case BinaryOperator::EQ:
- return ValMgr.makeTruthVal(false, resultTy);
- case BinaryOperator::NE:
- return ValMgr.makeTruthVal(true, resultTy);
- default:
- // This case also handles pointer arithmetic.
- return UnknownVal();
- }
- }
- }
- case nonloc::SymExprValKind: {
- // Logical not?
- if (!(op == BinaryOperator::EQ && rhs.isZeroConstant()))
- return UnknownVal();
-
- const SymExpr *symExpr =
- cast<nonloc::SymExprVal>(lhs).getSymbolicExpression();
-
- // Only handle ($sym op constant) for now.
- if (const SymIntExpr *symIntExpr = dyn_cast<SymIntExpr>(symExpr)) {
- BinaryOperator::Opcode opc = symIntExpr->getOpcode();
- switch (opc) {
- case BinaryOperator::LAnd:
- case BinaryOperator::LOr:
- assert(false && "Logical operators handled by branching logic.");
- return UnknownVal();
- case BinaryOperator::Assign:
- case BinaryOperator::MulAssign:
- case BinaryOperator::DivAssign:
- case BinaryOperator::RemAssign:
- case BinaryOperator::AddAssign:
- case BinaryOperator::SubAssign:
- case BinaryOperator::ShlAssign:
- case BinaryOperator::ShrAssign:
- case BinaryOperator::AndAssign:
- case BinaryOperator::XorAssign:
- case BinaryOperator::OrAssign:
- case BinaryOperator::Comma:
- assert(false && "'=' and ',' operators handled by GRExprEngine.");
- return UnknownVal();
- case BinaryOperator::PtrMemD:
- case BinaryOperator::PtrMemI:
- assert(false && "Pointer arithmetic not handled here.");
- return UnknownVal();
- case BinaryOperator::Mul:
- case BinaryOperator::Div:
- case BinaryOperator::Rem:
- case BinaryOperator::Add:
- case BinaryOperator::Sub:
- case BinaryOperator::Shl:
- case BinaryOperator::Shr:
- case BinaryOperator::And:
- case BinaryOperator::Xor:
- case BinaryOperator::Or:
- // Not handled yet.
- return UnknownVal();
- case BinaryOperator::LT:
- case BinaryOperator::GT:
- case BinaryOperator::LE:
- case BinaryOperator::GE:
- case BinaryOperator::EQ:
- case BinaryOperator::NE:
- opc = NegateComparison(opc);
- assert(symIntExpr->getType(ValMgr.getContext()) == resultTy);
- return ValMgr.makeNonLoc(symIntExpr->getLHS(), opc,
- symIntExpr->getRHS(), resultTy);
- }
- }
- }
- case nonloc::ConcreteIntKind: {
- if (isa<nonloc::ConcreteInt>(rhs)) {
- const nonloc::ConcreteInt& lhsInt = cast<nonloc::ConcreteInt>(lhs);
- return lhsInt.evalBinOp(ValMgr, op, cast<nonloc::ConcreteInt>(rhs));
- }
- else {
- // 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).
- NonLoc tmp = rhs;
- rhs = lhs;
- lhs = tmp;
-
- switch (op) {
- case BinaryOperator::LT: op = BinaryOperator::GT; continue;
- case BinaryOperator::GT: op = BinaryOperator::LT; continue;
- case BinaryOperator::LE: op = BinaryOperator::GE; continue;
- case BinaryOperator::GE: op = BinaryOperator::LE; continue;
- case BinaryOperator::EQ:
- case BinaryOperator::NE:
- case BinaryOperator::Add:
- case BinaryOperator::Mul:
- continue;
- 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(ValMgr.getContext())->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.
- BasicValueFactory &BVF = ValMgr.getBasicValueFactory();
- const llvm::APSInt &lhs_I = BVF.Convert(resultTy, *Constant);
- lhs = nonloc::ConcreteInt(lhs_I);
-
- // Also promote the RHS (if necessary).
-
- // For shifts, it necessary promote the RHS to the result type.
- 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(BVF.Convert(resultTy, rhs_I->getValue()));
- }
-
- continue;
- }
-
- if (isa<nonloc::ConcreteInt>(rhs)) {
- return ValMgr.makeNonLoc(slhs->getSymbol(), op,
- cast<nonloc::ConcreteInt>(rhs).getValue(),
- resultTy);
- }
-
- return UnknownVal();
- }
- }
- }
-}
-
-SVal SimpleSValuator::EvalBinOpLL(BinaryOperator::Opcode op, Loc lhs, Loc rhs,
- QualType resultTy) {
- switch (op) {
- default:
- return UnknownVal();
- case BinaryOperator::EQ:
- case BinaryOperator::NE:
- return EvalEquality(ValMgr, lhs, rhs, op == BinaryOperator::EQ, resultTy);
- case BinaryOperator::LT:
- case BinaryOperator::GT:
- // FIXME: Generalize. For now, just handle the trivial case where
- // the two locations are identical.
- if (lhs == rhs)
- return ValMgr.makeTruthVal(false, resultTy);
- return UnknownVal();
- }
-}
-
-SVal SimpleSValuator::EvalBinOpLN(const GRState *state,
- BinaryOperator::Opcode op,
- Loc lhs, NonLoc rhs, QualType resultTy) {
- // 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::isEqualityOp(op)) {
- if (nonloc::ConcreteInt *rhsInt = dyn_cast<nonloc::ConcreteInt>(&rhs)) {
- const llvm::APSInt *x = &rhsInt->getValue();
- ASTContext &ctx = ValMgr.getContext();
- if (ctx.getTypeSize(ctx.VoidPtrTy) == x->getBitWidth()) {
- // Convert the signedness of the integer (if necessary).
- if (x->isSigned())
- x = &ValMgr.getBasicValueFactory().getValue(*x, true);
-
- return EvalBinOpLL(op, lhs, loc::ConcreteInt(*x), resultTy);
- }
- }
- }
-
- // Delegate pointer arithmetic to the StoreManager.
- return state->getStateManager().getStoreManager().EvalBinOp(state, op, lhs,
- rhs, resultTy);
-}
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