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| author | rdivacky <rdivacky@FreeBSD.org> | 2009-11-04 15:04:32 +0000 |
|---|---|---|
| committer | rdivacky <rdivacky@FreeBSD.org> | 2009-11-04 15:04:32 +0000 |
| commit | b6d5e15aae202f157c6cd63da8fa4b089e7b31e9 (patch) | |
| tree | 59e0e47a9831dcf0e21e547927c8ebb7e113bfd1 /lib/Analysis/DivZeroChecker.cpp | |
| parent | 5563df30b9c8d1fe87a54baae0d6bd86642563f4 (diff) | |
| download | FreeBSD-src-b6d5e15aae202f157c6cd63da8fa4b089e7b31e9.zip FreeBSD-src-b6d5e15aae202f157c6cd63da8fa4b089e7b31e9.tar.gz | |
Update clang to r86025.
Diffstat (limited to 'lib/Analysis/DivZeroChecker.cpp')
| -rw-r--r-- | lib/Analysis/DivZeroChecker.cpp | 70 |
1 files changed, 70 insertions, 0 deletions
diff --git a/lib/Analysis/DivZeroChecker.cpp b/lib/Analysis/DivZeroChecker.cpp new file mode 100644 index 0000000..9c2359f --- /dev/null +++ b/lib/Analysis/DivZeroChecker.cpp @@ -0,0 +1,70 @@ +//== DivZeroChecker.cpp - Division by zero checker --------------*- C++ -*--==// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This defines DivZeroChecker, a builtin check in GRExprEngine that performs +// checks for division by zeros. +// +//===----------------------------------------------------------------------===// + +#include "clang/Analysis/PathSensitive/Checkers/DivZeroChecker.h" + +using namespace clang; + +void *DivZeroChecker::getTag() { + static int x; + return &x; +} + +void DivZeroChecker::PreVisitBinaryOperator(CheckerContext &C, + const BinaryOperator *B) { + BinaryOperator::Opcode Op = B->getOpcode(); + if (Op != BinaryOperator::Div && + Op != BinaryOperator::Rem && + Op != BinaryOperator::DivAssign && + Op != BinaryOperator::RemAssign) + return; + + if (!B->getRHS()->getType()->isIntegerType() || + !B->getRHS()->getType()->isScalarType()) + return; + + SVal Denom = C.getState()->getSVal(B->getRHS()); + const DefinedSVal *DV = dyn_cast<DefinedSVal>(&Denom); + + // Divide-by-undefined handled in the generic checking for uses of + // undefined values. + if (!DV) + return; + + // Check for divide by zero. + ConstraintManager &CM = C.getConstraintManager(); + const GRState *stateNotZero, *stateZero; + llvm::tie(stateNotZero, stateZero) = CM.AssumeDual(C.getState(), *DV); + + if (stateZero && !stateNotZero) { + if (ExplodedNode *N = C.GenerateNode(B, stateZero, true)) { + if (!BT) + BT = new BuiltinBug(0, "Division by zero"); + + EnhancedBugReport *R = + new EnhancedBugReport(*BT, BT->getDescription().c_str(), N); + + R->addVisitorCreator(bugreporter::registerTrackNullOrUndefValue, + bugreporter::GetDenomExpr(N)); + + C.EmitReport(R); + } + return; + } + + // If we get here, then the denom should not be zero. We abandon the implicit + // zero denom case for now. + if (stateNotZero != C.getState()) + C.addTransition(C.GenerateNode(B, stateNotZero)); +} |
