llvm-project/clang/lib/StaticAnalyzer/Core/CheckerHelpers.cpp

151 lines
4.2 KiB
C++

//===---- CheckerHelpers.cpp - Helper functions for checkers ----*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file defines several static functions for use in checkers.
//
//===----------------------------------------------------------------------===//
#include "clang/StaticAnalyzer/Core/PathSensitive/CheckerHelpers.h"
#include "clang/AST/Decl.h"
#include "clang/AST/Expr.h"
#include "clang/Lex/Preprocessor.h"
namespace clang {
namespace ento {
// Recursively find any substatements containing macros
bool containsMacro(const Stmt *S) {
if (S->getBeginLoc().isMacroID())
return true;
if (S->getEndLoc().isMacroID())
return true;
for (const Stmt *Child : S->children())
if (Child && containsMacro(Child))
return true;
return false;
}
// Recursively find any substatements containing enum constants
bool containsEnum(const Stmt *S) {
const DeclRefExpr *DR = dyn_cast<DeclRefExpr>(S);
if (DR && isa<EnumConstantDecl>(DR->getDecl()))
return true;
for (const Stmt *Child : S->children())
if (Child && containsEnum(Child))
return true;
return false;
}
// Recursively find any substatements containing static vars
bool containsStaticLocal(const Stmt *S) {
const DeclRefExpr *DR = dyn_cast<DeclRefExpr>(S);
if (DR)
if (const VarDecl *VD = dyn_cast<VarDecl>(DR->getDecl()))
if (VD->isStaticLocal())
return true;
for (const Stmt *Child : S->children())
if (Child && containsStaticLocal(Child))
return true;
return false;
}
// Recursively find any substatements containing __builtin_offsetof
bool containsBuiltinOffsetOf(const Stmt *S) {
if (isa<OffsetOfExpr>(S))
return true;
for (const Stmt *Child : S->children())
if (Child && containsBuiltinOffsetOf(Child))
return true;
return false;
}
// Extract lhs and rhs from assignment statement
std::pair<const clang::VarDecl *, const clang::Expr *>
parseAssignment(const Stmt *S) {
const VarDecl *VD = nullptr;
const Expr *RHS = nullptr;
if (auto Assign = dyn_cast_or_null<BinaryOperator>(S)) {
if (Assign->isAssignmentOp()) {
// Ordinary assignment
RHS = Assign->getRHS();
if (auto DE = dyn_cast_or_null<DeclRefExpr>(Assign->getLHS()))
VD = dyn_cast_or_null<VarDecl>(DE->getDecl());
}
} else if (auto PD = dyn_cast_or_null<DeclStmt>(S)) {
// Initialization
assert(PD->isSingleDecl() && "We process decls one by one");
VD = cast<VarDecl>(PD->getSingleDecl());
RHS = VD->getAnyInitializer();
}
return std::make_pair(VD, RHS);
}
Nullability getNullabilityAnnotation(QualType Type) {
const auto *AttrType = Type->getAs<AttributedType>();
if (!AttrType)
return Nullability::Unspecified;
if (AttrType->getAttrKind() == attr::TypeNullable)
return Nullability::Nullable;
else if (AttrType->getAttrKind() == attr::TypeNonNull)
return Nullability::Nonnull;
return Nullability::Unspecified;
}
llvm::Optional<int> tryExpandAsInteger(StringRef Macro,
const Preprocessor &PP) {
const auto *MacroII = PP.getIdentifierInfo(Macro);
if (!MacroII)
return llvm::None;
const MacroInfo *MI = PP.getMacroInfo(MacroII);
if (!MI)
return llvm::None;
// Filter out parens.
std::vector<Token> FilteredTokens;
FilteredTokens.reserve(MI->tokens().size());
for (auto &T : MI->tokens())
if (!T.isOneOf(tok::l_paren, tok::r_paren))
FilteredTokens.push_back(T);
// Parse an integer at the end of the macro definition.
const Token &T = FilteredTokens.back();
if (!T.isLiteral())
return llvm::None;
StringRef ValueStr = StringRef(T.getLiteralData(), T.getLength());
llvm::APInt IntValue;
constexpr unsigned AutoSenseRadix = 0;
if (ValueStr.getAsInteger(AutoSenseRadix, IntValue))
return llvm::None;
// Parse an optional minus sign.
size_t Size = FilteredTokens.size();
if (Size >= 2) {
if (FilteredTokens[Size - 2].is(tok::minus))
IntValue = -IntValue;
}
return IntValue.getSExtValue();
}
} // namespace ento
} // namespace clang