Chris Lattner has strong opinions about directory
layout. :)
Rename the 'EntoSA' directories to 'StaticAnalyzer'.
Internally we will still use the 'ento' namespace
for the analyzer engine (unless there are further
sabre rattlings...).
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@122514 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/StaticAnalyzer/Checkers/ArrayBoundChecker.cpp b/lib/StaticAnalyzer/Checkers/ArrayBoundChecker.cpp
new file mode 100644
index 0000000..13e628b
--- /dev/null
+++ b/lib/StaticAnalyzer/Checkers/ArrayBoundChecker.cpp
@@ -0,0 +1,91 @@
+//== ArrayBoundChecker.cpp ------------------------------*- C++ -*--==//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines ArrayBoundChecker, which is a path-sensitive check
+// which looks for an out-of-bound array element access.
+//
+//===----------------------------------------------------------------------===//
+
+#include "ExprEngineInternalChecks.h"
+#include "clang/StaticAnalyzer/BugReporter/BugType.h"
+#include "clang/StaticAnalyzer/PathSensitive/CheckerVisitor.h"
+#include "clang/StaticAnalyzer/PathSensitive/ExprEngine.h"
+
+using namespace clang;
+using namespace ento;
+
+namespace {
+class ArrayBoundChecker :
+ public CheckerVisitor<ArrayBoundChecker> {
+ BuiltinBug *BT;
+public:
+ ArrayBoundChecker() : BT(0) {}
+ static void *getTag() { static int x = 0; return &x; }
+ void visitLocation(CheckerContext &C, const Stmt *S, SVal l);
+};
+}
+
+void ento::RegisterArrayBoundChecker(ExprEngine &Eng) {
+ Eng.registerCheck(new ArrayBoundChecker());
+}
+
+void ArrayBoundChecker::visitLocation(CheckerContext &C, const Stmt *S, SVal l){
+ // Check for out of bound array element access.
+ const MemRegion *R = l.getAsRegion();
+ if (!R)
+ return;
+
+ const ElementRegion *ER = dyn_cast<ElementRegion>(R);
+ if (!ER)
+ return;
+
+ // Get the index of the accessed element.
+ DefinedOrUnknownSVal Idx = cast<DefinedOrUnknownSVal>(ER->getIndex());
+
+ // Zero index is always in bound, this also passes ElementRegions created for
+ // pointer casts.
+ if (Idx.isZeroConstant())
+ return;
+
+ const GRState *state = C.getState();
+
+ // Get the size of the array.
+ DefinedOrUnknownSVal NumElements
+ = C.getStoreManager().getSizeInElements(state, ER->getSuperRegion(),
+ ER->getValueType());
+
+ const GRState *StInBound = state->assumeInBound(Idx, NumElements, true);
+ const GRState *StOutBound = state->assumeInBound(Idx, NumElements, false);
+ if (StOutBound && !StInBound) {
+ ExplodedNode *N = C.generateSink(StOutBound);
+ if (!N)
+ return;
+
+ if (!BT)
+ BT = new BuiltinBug("Out-of-bound array access",
+ "Access out-of-bound array element (buffer overflow)");
+
+ // FIXME: It would be nice to eventually make this diagnostic more clear,
+ // e.g., by referencing the original declaration or by saying *why* this
+ // reference is outside the range.
+
+ // Generate a report for this bug.
+ RangedBugReport *report =
+ new RangedBugReport(*BT, BT->getDescription(), N);
+
+ report->addRange(S->getSourceRange());
+ C.EmitReport(report);
+ return;
+ }
+
+ // Array bound check succeeded. From this point forward the array bound
+ // should always succeed.
+ assert(StInBound);
+ C.addTransition(StInBound);
+}