#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/Statistic.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/Support/Casting.h"
// Implementation of FalsePositiveRefutationBRVisitor.
//===----------------------------------------------------------------------===//
+#define DEBUG_TYPE "FalsePositiveRefutationBRVisitor"
+STATISTIC(CrosscheckedBugReports,
+ "The # of bug reports which were checked for infeasible constraints");
+STATISTIC(CrosscheckInvalidatedBugReports,
+ "The # of bug reports invalidated due to infeasible constraints");
+
FalsePositiveRefutationBRVisitor::FalsePositiveRefutationBRVisitor()
: Constraints(ConstraintRangeTy::Factory().getEmptyMap()) {}
void FalsePositiveRefutationBRVisitor::finalizeVisitor(
BugReporterContext &BRC, const ExplodedNode *EndPathNode,
PathSensitiveBugReport &BR) {
+ ++CrosscheckedBugReports;
// Collect new constraints
VisitNode(EndPathNode, BRC, BR);
if (!isSat.hasValue())
return;
- if (!isSat.getValue())
+ if (!isSat.getValue()) {
+ ++CrosscheckInvalidatedBugReports;
BR.markInvalid("Infeasible constraints", EndPathNode->getLocationContext());
+ }
}
PathDiagnosticPieceRef FalsePositiveRefutationBRVisitor::VisitNode(
#include "clang/StaticAnalyzer/Frontend/AnalysisConsumer.h"
#include "clang/StaticAnalyzer/Frontend/CheckerRegistry.h"
#include "clang/Tooling/Tooling.h"
+#include "gtest/gtest.h"
namespace clang {
namespace ento {
}
};
+inline SmallString<80> getCurrentTestNameAsFileName() {
+ const ::testing::TestInfo *Info =
+ ::testing::UnitTest::GetInstance()->current_test_info();
+
+ SmallString<80> FileName;
+ (Twine{Info->name()} + ".cc").toVector(FileName);
+ return FileName;
+}
+
template <AddCheckerFn... Fns>
bool runCheckerOnCode(const std::string &Code, std::string &Diags) {
+ const SmallVectorImpl<char> &FileName = getCurrentTestNameAsFileName();
llvm::raw_string_ostream OS(Diags);
- return tooling::runToolOnCode(std::make_unique<TestAction<Fns...>>(OS), Code);
+ return tooling::runToolOnCode(std::make_unique<TestAction<Fns...>>(OS), Code,
+ FileName);
}
template <AddCheckerFn... Fns>
return runCheckerOnCode<Fns...>(Code, Diags);
}
+template <AddCheckerFn... Fns>
+bool runCheckerOnCodeWithArgs(const std::string &Code,
+ const std::vector<std::string> &Args,
+ std::string &Diags) {
+ const SmallVectorImpl<char> &FileName = getCurrentTestNameAsFileName();
+ llvm::raw_string_ostream OS(Diags);
+ return tooling::runToolOnCodeWithArgs(
+ std::make_unique<TestAction<Fns...>>(OS), Code, Args, FileName);
+}
+
+template <AddCheckerFn... Fns>
+bool runCheckerOnCodeWithArgs(const std::string &Code,
+ const std::vector<std::string> &Args) {
+ std::string Diags;
+ return runCheckerOnCodeWithArgs<Fns...>(Code, Args, Diags);
+}
+
} // namespace ento
} // namespace clang
--- /dev/null
+//===- unittests/StaticAnalyzer/FalsePositiveRefutationBRVisitorTest.cpp --===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "CheckerRegistration.h"
+#include "Reusables.h"
+#include "clang/Frontend/CompilerInstance.h"
+#include "clang/StaticAnalyzer/Core/BugReporter/BugReporter.h"
+#include "clang/StaticAnalyzer/Core/BugReporter/BugType.h"
+#include "clang/StaticAnalyzer/Core/Checker.h"
+#include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h"
+#include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h"
+#include "clang/StaticAnalyzer/Frontend/AnalysisConsumer.h"
+#include "clang/StaticAnalyzer/Frontend/CheckerRegistry.h"
+#include "llvm/Config/config.h"
+#include "gtest/gtest.h"
+
+// FIXME: Use GTEST_SKIP() instead if GTest is updated to version 1.10.0
+#define SKIP_WITHOUT_Z3 \
+ do \
+ if (!LLVM_WITH_Z3) \
+ return; \
+ while (0)
+
+namespace clang {
+namespace ento {
+namespace {
+
+class FalsePositiveGenerator : public Checker<eval::Call> {
+ using Self = FalsePositiveGenerator;
+ const BuiltinBug FalsePositiveGeneratorBug{this, "FalsePositiveGenerator"};
+ using HandlerFn = bool (Self::*)(const CallEvent &Call,
+ CheckerContext &) const;
+ CallDescriptionMap<HandlerFn> Callbacks = {
+ {{"reachedWithContradiction", 0}, &Self::reachedWithContradiction},
+ {{"reachedWithNoContradiction", 0}, &Self::reachedWithNoContradiction},
+ {{"reportIfCanBeTrue", 1}, &Self::reportIfCanBeTrue},
+ };
+
+ bool report(CheckerContext &C, ProgramStateRef State,
+ StringRef Description) const {
+ ExplodedNode *Node = C.generateNonFatalErrorNode(State);
+ if (!Node)
+ return false;
+
+ auto Report = std::make_unique<PathSensitiveBugReport>(
+ FalsePositiveGeneratorBug, Description, Node);
+ C.emitReport(std::move(Report));
+ return true;
+ }
+
+ bool reachedWithNoContradiction(const CallEvent &, CheckerContext &C) const {
+ return report(C, C.getState(), "REACHED_WITH_NO_CONTRADICTION");
+ }
+
+ bool reachedWithContradiction(const CallEvent &, CheckerContext &C) const {
+ return report(C, C.getState(), "REACHED_WITH_CONTRADICTION");
+ }
+
+ // Similar to ExprInspectionChecker::analyzerEval except it emits warning only
+ // if the argument can be true. The report emits the report in the state where
+ // the assertion true.
+ bool reportIfCanBeTrue(const CallEvent &Call, CheckerContext &C) const {
+ // A specific instantiation of an inlined function may have more constrained
+ // values than can generally be assumed. Skip the check.
+ if (C.getPredecessor()->getLocationContext()->getStackFrame()->getParent())
+ return false;
+
+ SVal AssertionVal = Call.getArgSVal(0);
+ if (AssertionVal.isUndef())
+ return false;
+
+ ProgramStateRef State = C.getPredecessor()->getState();
+ ProgramStateRef StTrue;
+ std::tie(StTrue, std::ignore) =
+ State->assume(AssertionVal.castAs<DefinedOrUnknownSVal>());
+ if (StTrue)
+ return report(C, StTrue, "CAN_BE_TRUE");
+ return false;
+ }
+
+public:
+ bool evalCall(const CallEvent &Call, CheckerContext &C) const {
+ if (const HandlerFn *Callback = Callbacks.lookup(Call))
+ return (this->*(*Callback))(Call, C);
+ return false;
+ }
+};
+
+void addFalsePositiveGenerator(AnalysisASTConsumer &AnalysisConsumer,
+ AnalyzerOptions &AnOpts) {
+ AnOpts.CheckersAndPackages = {{"test.FalsePositiveGenerator", true},
+ {"debug.ViewExplodedGraph", false}};
+ AnalysisConsumer.AddCheckerRegistrationFn([](CheckerRegistry &Registry) {
+ Registry.addChecker<FalsePositiveGenerator>(
+ "test.FalsePositiveGenerator", "EmptyDescription", "EmptyDocsUri");
+ });
+}
+
+// C++20 use constexpr below.
+const std::vector<std::string> LazyAssumeArgs{
+ "-Xclang", "-analyzer-config", "-Xclang", "eagerly-assume=false"};
+const std::vector<std::string> LazyAssumeAndCrossCheckArgs{
+ "-Xclang", "-analyzer-config", "-Xclang", "eagerly-assume=false",
+ "-Xclang", "-analyzer-config", "-Xclang", "crosscheck-with-z3=true"};
+
+TEST(FalsePositiveRefutationBRVisitor, UnSatInTheMiddleNoReport) {
+ SKIP_WITHOUT_Z3;
+ constexpr auto Code = R"(
+ void reachedWithContradiction();
+ void reachedWithNoContradiction();
+ void test(int x, int y) {
+ if (x * y == 0)
+ return;
+ reachedWithNoContradiction();
+ if (x == 0) {
+ reachedWithContradiction();
+ // x * y != 0 => x != 0 && y != 0 => contradict with x == 0
+ }
+ })";
+
+ std::string Diags;
+ EXPECT_TRUE(runCheckerOnCodeWithArgs<addFalsePositiveGenerator>(
+ Code, LazyAssumeAndCrossCheckArgs, Diags));
+ EXPECT_EQ(Diags,
+ "test.FalsePositiveGenerator:REACHED_WITH_NO_CONTRADICTION\n");
+ // Single warning. The second report was invalidated by the visitor.
+
+ // Without enabling the crosscheck-with-z3 both reports are displayed.
+ std::string Diags2;
+ EXPECT_TRUE(runCheckerOnCodeWithArgs<addFalsePositiveGenerator>(
+ Code, LazyAssumeArgs, Diags2));
+ EXPECT_EQ(Diags2,
+ "test.FalsePositiveGenerator:REACHED_WITH_NO_CONTRADICTION\n"
+ "test.FalsePositiveGenerator:REACHED_WITH_CONTRADICTION\n");
+}
+
+TEST(FalsePositiveRefutationBRVisitor, UnSatAtErrorNodeWithNewSymbolNoReport) {
+ SKIP_WITHOUT_Z3;
+ constexpr auto Code = R"(
+ void reportIfCanBeTrue(bool);
+ void reachedWithNoContradiction();
+ void test(int x, int y) {
+ if (x * y == 0)
+ return;
+ // We know that 'x * y': {[MIN,-1], [1,MAX]}
+ reachedWithNoContradiction();
+ reportIfCanBeTrue(x == 0); // contradiction
+ // The function introduces the 'x == 0' constraint in the ErrorNode which
+ // leads to contradiction with the constraint of 'x * y'.
+ // Note that the new constraint was bound to a new symbol 'x'.
+ })";
+ std::string Diags;
+ EXPECT_TRUE(runCheckerOnCodeWithArgs<addFalsePositiveGenerator>(
+ Code, LazyAssumeAndCrossCheckArgs, Diags));
+ EXPECT_EQ(Diags,
+ "test.FalsePositiveGenerator:REACHED_WITH_NO_CONTRADICTION\n");
+ // Single warning. The second report was invalidated by the visitor.
+
+ // Without enabling the crosscheck-with-z3 both reports are displayed.
+ std::string Diags2;
+ EXPECT_TRUE(runCheckerOnCodeWithArgs<addFalsePositiveGenerator>(
+ Code, LazyAssumeArgs, Diags2));
+ EXPECT_EQ(Diags2,
+ "test.FalsePositiveGenerator:REACHED_WITH_NO_CONTRADICTION\n"
+ "test.FalsePositiveGenerator:CAN_BE_TRUE\n");
+}
+
+} // namespace
+} // namespace ento
+} // namespace clang