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

150 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/Checker/PathSensitive/ValueManager.h"
#include "clang/Analysis/AnalysisContext.h"
using namespace clang;
using namespace llvm;
//===----------------------------------------------------------------------===//
// Utility methods for constructing SVals.
//===----------------------------------------------------------------------===//
DefinedOrUnknownSVal 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);
}
DefinedOrUnknownSVal
ValueManager::getRegionValueSymbolVal(const TypedRegion* R) {
QualType T = R->getValueType(SymMgr.getContext());
if (!SymbolManager::canSymbolicate(T))
return UnknownVal();
SymbolRef sym = SymMgr.getRegionValueSymbol(R);
if (Loc::IsLocType(T))
return loc::MemRegionVal(MemMgr.getSymbolicRegion(sym));
return nonloc::SymbolVal(sym);
}
DefinedOrUnknownSVal ValueManager::getConjuredSymbolVal(const void *SymbolTag,
const Expr *E,
unsigned Count) {
QualType T = E->getType();
if (!SymbolManager::canSymbolicate(T))
return UnknownVal();
SymbolRef sym = SymMgr.getConjuredSymbol(E, Count, SymbolTag);
if (Loc::IsLocType(T))
return loc::MemRegionVal(MemMgr.getSymbolicRegion(sym));
return nonloc::SymbolVal(sym);
}
DefinedOrUnknownSVal ValueManager::getConjuredSymbolVal(const void *SymbolTag,
const Expr *E,
QualType T,
unsigned Count) {
if (!SymbolManager::canSymbolicate(T))
return UnknownVal();
SymbolRef sym = SymMgr.getConjuredSymbol(E, T, Count, SymbolTag);
if (Loc::IsLocType(T))
return loc::MemRegionVal(MemMgr.getSymbolicRegion(sym));
return nonloc::SymbolVal(sym);
}
DefinedOrUnknownSVal
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);
}
DefinedSVal ValueManager::getFunctionPointer(const FunctionDecl* FD) {
return loc::MemRegionVal(MemMgr.getFunctionTextRegion(FD));
}
DefinedSVal ValueManager::getBlockPointer(const BlockDecl *D,
CanQualType locTy,
const LocationContext *LC) {
const BlockTextRegion *BC =
MemMgr.getBlockTextRegion(D, locTy, LC->getAnalysisContext());
const BlockDataRegion *BD = MemMgr.getBlockDataRegion(BC, LC);
return loc::MemRegionVal(BD);
}