From b6d5e15aae202f157c6cd63da8fa4b089e7b31e9 Mon Sep 17 00:00:00 2001
From: rdivacky <rdivacky@FreeBSD.org>
Date: Wed, 4 Nov 2009 15:04:32 +0000
Subject: Update clang to r86025.
---
lib/Analysis/DivZeroChecker.cpp | 70 +++++++++++++++++++++++++++++++++++++++++
1 file changed, 70 insertions(+)
create mode 100644 lib/Analysis/DivZeroChecker.cpp
(limited to 'lib/Analysis/DivZeroChecker.cpp')
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));
+}
--
cgit v1.1