llvm-project/clang/lib/Analysis/ValueManager.cpp

154 lines
4.9 KiB
C++

//== ValueManager.cpp - Aggregate manager of symbols and SVals --*- 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 ValueManager, a class that manages symbolic values
// and SVals created for use by GRExprEngine and related classes. It
// wraps and owns SymbolManager, MemRegionManager, and BasicValueFactory.
//
//===----------------------------------------------------------------------===//
#include "clang/Analysis/PathSensitive/ValueManager.h"
using namespace clang;
using namespace llvm;
//===----------------------------------------------------------------------===//
// Utility methods for constructing SVals.
//===----------------------------------------------------------------------===//
SVal ValueManager::makeZeroVal(QualType T) {
if (Loc::IsLocType(T))
return makeNull();
if (T->isIntegerType())
return makeIntVal(0, T);
// FIXME: Handle floats.
// FIXME: Handle structs.
return UnknownVal();
}
//===----------------------------------------------------------------------===//
// Utility methods for constructing Non-Locs.
//===----------------------------------------------------------------------===//
NonLoc ValueManager::makeNonLoc(const SymExpr *lhs, BinaryOperator::Opcode op,
const APSInt& v, QualType T) {
// The Environment ensures we always get a persistent APSInt in
// BasicValueFactory, so we don't need to get the APSInt from
// BasicValueFactory again.
assert(!Loc::IsLocType(T));
return nonloc::SymExprVal(SymMgr.getSymIntExpr(lhs, op, v, T));
}
NonLoc ValueManager::makeNonLoc(const SymExpr *lhs, BinaryOperator::Opcode op,
const SymExpr *rhs, QualType T) {
assert(SymMgr.getType(lhs) == SymMgr.getType(rhs));
assert(!Loc::IsLocType(T));
return nonloc::SymExprVal(SymMgr.getSymSymExpr(lhs, op, rhs, T));
}
SVal ValueManager::convertToArrayIndex(SVal V) {
if (V.isUnknownOrUndef())
return V;
// Common case: we have an appropriately sized integer.
if (nonloc::ConcreteInt* CI = dyn_cast<nonloc::ConcreteInt>(&V)) {
const llvm::APSInt& I = CI->getValue();
if (I.getBitWidth() == ArrayIndexWidth && I.isSigned())
return V;
}
return SVator->EvalCastNL(cast<NonLoc>(V), ArrayIndexTy);
}
SVal ValueManager::getRegionValueSymbolVal(const MemRegion* R, QualType T) {
if (T.isNull()) {
const TypedRegion* TR = cast<TypedRegion>(R);
T = TR->getValueType(SymMgr.getContext());
}
if (!SymbolManager::canSymbolicate(T))
return UnknownVal();
SymbolRef sym = SymMgr.getRegionValueSymbol(R, T);
// If T is of function pointer type or a block pointer type, create a
// CodeTextRegion wrapping that symbol.
if (T->isFunctionPointerType() || T->isBlockPointerType())
return loc::MemRegionVal(MemMgr.getCodeTextRegion(sym, T));
if (Loc::IsLocType(T))
return loc::MemRegionVal(MemMgr.getSymbolicRegion(sym));
return nonloc::SymbolVal(sym);
}
SVal ValueManager::getConjuredSymbolVal(const Expr* E, unsigned Count) {
QualType T = E->getType();
if (!SymbolManager::canSymbolicate(T))
return UnknownVal();
SymbolRef sym = SymMgr.getConjuredSymbol(E, Count);
// If T is of function pointer type or a block pointer type, create a
// CodeTextRegion wrapping a symbol.
if (T->isFunctionPointerType() || T->isBlockPointerType())
return loc::MemRegionVal(MemMgr.getCodeTextRegion(sym, T));
if (Loc::IsLocType(T))
return loc::MemRegionVal(MemMgr.getSymbolicRegion(sym));
return nonloc::SymbolVal(sym);
}
SVal ValueManager::getConjuredSymbolVal(const Expr* E, QualType T,
unsigned Count) {
if (!SymbolManager::canSymbolicate(T))
return UnknownVal();
SymbolRef sym = SymMgr.getConjuredSymbol(E, T, Count);
// If T is of function pointer type or a block pointer type, create a
// CodeTextRegion wrapping a symbol.
if (T->isFunctionPointerType() || T->isBlockPointerType())
return loc::MemRegionVal(MemMgr.getCodeTextRegion(sym, T));
if (Loc::IsLocType(T))
return loc::MemRegionVal(MemMgr.getSymbolicRegion(sym));
return nonloc::SymbolVal(sym);
}
SVal ValueManager::getDerivedRegionValueSymbolVal(SymbolRef parentSymbol,
const TypedRegion *R) {
QualType T = R->getValueType(R->getContext());
if (!SymbolManager::canSymbolicate(T))
return UnknownVal();
SymbolRef sym = SymMgr.getDerivedSymbol(parentSymbol, R);
if (Loc::IsLocType(T))
return loc::MemRegionVal(MemMgr.getSymbolicRegion(sym));
return nonloc::SymbolVal(sym);
}
SVal ValueManager::getFunctionPointer(const FunctionDecl* FD) {
CodeTextRegion* R
= MemMgr.getCodeTextRegion(FD, Context.getPointerType(FD->getType()));
return loc::MemRegionVal(R);
}