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//== Environment.cpp - Map from Expr* to Locations/Values -------*- C++ -*--==//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defined the Environment and EnvironmentManager classes.
//
//===----------------------------------------------------------------------===//
#include "clang/Analysis/PathSensitive/Environment.h"
#include "clang/Analysis/Analyses/LiveVariables.h"
#include "llvm/ADT/ImmutableMap.h"
#include "llvm/Support/Streams.h"
using namespace clang;
RVal Environment::GetRVal(Expr* E, BasicValueFactory& BasicVals) const {
for (;;) {
switch (E->getStmtClass()) {
case Stmt::AddrLabelExprClass:
return LVal::MakeVal(cast<AddrLabelExpr>(E));
// ParenExprs are no-ops.
case Stmt::ParenExprClass:
E = cast<ParenExpr>(E)->getSubExpr();
continue;
case Stmt::CharacterLiteralClass: {
CharacterLiteral* C = cast<CharacterLiteral>(E);
return NonLVal::MakeVal(BasicVals, C->getValue(), C->getType());
}
case Stmt::IntegerLiteralClass: {
return NonLVal::MakeVal(BasicVals, cast<IntegerLiteral>(E));
}
case Stmt::StringLiteralClass:
return LVal::MakeVal(cast<StringLiteral>(E));
// Casts where the source and target type are the same
// are no-ops. We blast through these to get the descendant
// subexpression that has a value.
case Stmt::ImplicitCastExprClass:
case Stmt::ExplicitCastExprClass: {
CastExpr* C = cast<CastExpr>(E);
QualType CT = C->getType();
QualType ST = C->getSubExpr()->getType();
if (CT->isVoidType())
return UnknownVal();
break;
}
// Handle all other Expr* using a lookup.
default:
break;
};
break;
}
return LookupExpr(E);
}
RVal Environment::GetBlkExprRVal(Expr* E, BasicValueFactory& BasicVals) const {
E = E->IgnoreParens();
switch (E->getStmtClass()) {
case Stmt::CharacterLiteralClass: {
CharacterLiteral* C = cast<CharacterLiteral>(E);
return NonLVal::MakeVal(BasicVals, C->getValue(), C->getType());
}
case Stmt::IntegerLiteralClass: {
return NonLVal::MakeVal(BasicVals, cast<IntegerLiteral>(E));
}
default:
return LookupBlkExpr(E);
}
}
Environment EnvironmentManager::SetRVal(const Environment& Env, Expr* E, RVal V,
bool isBlkExpr, bool Invalidate) {
assert (E);
if (V.isUnknown()) {
if (Invalidate)
return isBlkExpr ? RemoveBlkExpr(Env, E) : RemoveSubExpr(Env, E);
else
return Env;
}
return isBlkExpr ? AddBlkExpr(Env, E, V) : AddSubExpr(Env, E, V);
}
Environment
EnvironmentManager::RemoveDeadBindings(Environment Env,
Stmt* Loc,
const LiveVariables& Liveness,
StoreManager::DeclRootsTy& DRoots,
StoreManager::LiveSymbolsTy& LSymbols) {
// Drop bindings for subexpressions.
Env = RemoveSubExprBindings(Env);
// Iterate over the block-expr bindings.
for (Environment::beb_iterator I = Env.beb_begin(), E = Env.beb_end();
I != E; ++I) {
Expr* BlkExpr = I.getKey();
if (Liveness.isLive(Loc, BlkExpr)) {
RVal X = I.getData();
// If the block expr's value is the address of some Decl, then mark that
// Decl.
if (isa<lval::DeclVal>(X)) {
lval::DeclVal LV = cast<lval::DeclVal>(X);
DRoots.push_back(LV.getDecl());
}
// Mark all symbols in the block expr's value.
for (RVal::symbol_iterator SI = X.symbol_begin(), SE = X.symbol_end();
SI != SE; ++SI) {
LSymbols.insert(*SI);
}
} else {
// The block expr is dead.
RVal X = I.getData();
// Do not misclean LogicalExpr or ConditionalOperator. It is dead at the
// beginning of itself, but we need its UndefinedVal to determine its
// RVal.
if (X.isUndef() && cast<UndefinedVal>(X).getData())
continue;
Env = RemoveBlkExpr(Env, BlkExpr);
}
}
return Env;
}
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