1 files changed, 85 insertions, 0 deletions
diff --git a/lib/StaticAnalyzer/Checkers/ExprInspectionChecker.cpp b/lib/StaticAnalyzer/Checkers/ExprInspectionChecker.cpp
new file mode 100644
index 0000000000..f638dda2d8
--- /dev/null
+++ b/lib/StaticAnalyzer/Checkers/ExprInspectionChecker.cpp
@@ -0,0 +1,85 @@
+//==- ExprInspectionChecker.cpp - Used for regression tests ------*- C++ -*-==//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "ClangSACheckers.h"
+#include "clang/StaticAnalyzer/Core/Checker.h"
+#include "clang/StaticAnalyzer/Core/BugReporter/BugType.h"
+#include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h"
+
+using namespace clang;
+using namespace ento;
+
+namespace {
+class ExprInspectionChecker : public Checker< eval::Call > {
+  mutable OwningPtr<BugType> BT;
+public:
+  bool evalCall(const CallExpr *CE, CheckerContext &C) const;
+};
+}
+
+bool ExprInspectionChecker::evalCall(const CallExpr *CE,
+                                       CheckerContext &C) const {
+  // These checks should have no effect on the surrounding environment
+  // (globals should not be evaluated, etc), hence the use of evalCall.
+  ExplodedNode *N = C.getPredecessor();
+  const LocationContext *LC = N->getLocationContext();
+
+  if (!C.getCalleeName(CE).equals("clang_analyzer_eval"))
+    return false;
+
+  // A specific instantiation of an inlined function may have more constrained
+  // values than can generally be assumed. Skip the check.
+  if (LC->getParent() != 0)
+    return true;
+
+  const char *Msg = 0;
+
+  if (CE->getNumArgs() == 0)
+    Msg = "Missing assertion argument";
+  else {
+    ProgramStateRef State = N->getState();
+    const Expr *Assertion = CE->getArg(0);
+    SVal AssertionVal = State->getSVal(Assertion, LC);
+
+    if (AssertionVal.isUndef())
+      Msg = "UNDEFINED";
+    else {
+      ProgramStateRef StTrue, StFalse;
+      llvm::tie(StTrue, StFalse) =
+        State->assume(cast<DefinedOrUnknownSVal>(AssertionVal));
+
+      if (StTrue) {
+        if (StFalse)
+          Msg = "UNKNOWN";
+        else
+          Msg = "TRUE";
+      } else {
+        if (StFalse)
+          Msg = "FALSE";
+        else
+          llvm_unreachable("Invalid constraint; neither true or false.");
+      }      
+    }
+  }
+
+  assert(Msg);
+
+  if (!BT)
+    BT.reset(new BugType("Checking analyzer assumptions", "debug"));
+
+  BugReport *R = new BugReport(*BT, Msg, N);
+  C.EmitReport(R);
+
+  return true;
+}
+
+void ento::registerExprInspectionChecker(CheckerManager &Mgr) {
+  Mgr.registerChecker<ExprInspectionChecker>();
+}
+