102 lines
3.8 KiB
C++
102 lines
3.8 KiB
C++
//== PointerIterationChecker.cpp ------------------------------- -*- 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 PointerIterationChecker which checks for non-determinism
|
|
// caused due to iteration of unordered containers of pointer elements.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#include "clang/ASTMatchers/ASTMatchFinder.h"
|
|
#include "clang/StaticAnalyzer/Checkers/BuiltinCheckerRegistration.h"
|
|
#include "clang/StaticAnalyzer/Core/Checker.h"
|
|
#include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h"
|
|
|
|
using namespace clang;
|
|
using namespace ento;
|
|
using namespace ast_matchers;
|
|
|
|
namespace {
|
|
|
|
// ID of a node at which the diagnostic would be emitted.
|
|
constexpr llvm::StringLiteral WarnAtNode = "iter";
|
|
|
|
class PointerIterationChecker : public Checker<check::ASTCodeBody> {
|
|
public:
|
|
void checkASTCodeBody(const Decl *D,
|
|
AnalysisManager &AM,
|
|
BugReporter &BR) const;
|
|
};
|
|
|
|
static void emitDiagnostics(const BoundNodes &Match, const Decl *D,
|
|
BugReporter &BR, AnalysisManager &AM,
|
|
const PointerIterationChecker *Checker) {
|
|
auto *ADC = AM.getAnalysisDeclContext(D);
|
|
|
|
const auto *MarkedStmt = Match.getNodeAs<Stmt>(WarnAtNode);
|
|
assert(MarkedStmt);
|
|
|
|
auto Range = MarkedStmt->getSourceRange();
|
|
auto Location = PathDiagnosticLocation::createBegin(MarkedStmt,
|
|
BR.getSourceManager(),
|
|
ADC);
|
|
std::string Diagnostics;
|
|
llvm::raw_string_ostream OS(Diagnostics);
|
|
OS << "Iteration of pointer-like elements "
|
|
<< "can result in non-deterministic ordering";
|
|
|
|
BR.EmitBasicReport(ADC->getDecl(), Checker,
|
|
"Iteration of pointer-like elements", "Non-determinism",
|
|
OS.str(), Location, Range);
|
|
}
|
|
|
|
// Assumption: Iteration of ordered containers of pointers is deterministic.
|
|
|
|
// TODO: Currently, we only check for std::unordered_set. Other unordered
|
|
// containers like std::unordered_map also need to be handled.
|
|
|
|
// TODO: Currently, we do not check what the for loop does with the iterated
|
|
// pointer values. Not all iterations may cause non-determinism. For example,
|
|
// counting or summing up the elements should not be non-deterministic.
|
|
|
|
auto matchUnorderedIterWithPointers() -> decltype(decl()) {
|
|
|
|
auto UnorderedContainerM = declRefExpr(to(varDecl(hasType(
|
|
recordDecl(hasName("std::unordered_set")
|
|
)))));
|
|
|
|
auto PointerTypeM = varDecl(hasType(hasCanonicalType(pointerType())));
|
|
|
|
auto PointerIterM = stmt(cxxForRangeStmt(
|
|
hasLoopVariable(PointerTypeM),
|
|
hasRangeInit(UnorderedContainerM)
|
|
)).bind(WarnAtNode);
|
|
|
|
return decl(forEachDescendant(PointerIterM));
|
|
}
|
|
|
|
void PointerIterationChecker::checkASTCodeBody(const Decl *D,
|
|
AnalysisManager &AM,
|
|
BugReporter &BR) const {
|
|
auto MatcherM = matchUnorderedIterWithPointers();
|
|
|
|
auto Matches = match(MatcherM, *D, AM.getASTContext());
|
|
for (const auto &Match : Matches)
|
|
emitDiagnostics(Match, D, BR, AM, this);
|
|
}
|
|
|
|
} // end of anonymous namespace
|
|
|
|
void ento::registerPointerIterationChecker(CheckerManager &Mgr) {
|
|
Mgr.registerChecker<PointerIterationChecker>();
|
|
}
|
|
|
|
bool ento::shouldRegisterPointerIterationChecker(const CheckerManager &mgr) {
|
|
const LangOptions &LO = mgr.getLangOpts();
|
|
return LO.CPlusPlus;
|
|
}
|