Index: include/clang/StaticAnalyzer/Core/PathSensitive/CheckerHelpers.h
===================================================================
--- include/clang/StaticAnalyzer/Core/PathSensitive/CheckerHelpers.h
+++ include/clang/StaticAnalyzer/Core/PathSensitive/CheckerHelpers.h
@@ -16,6 +16,7 @@
 
 #include "clang/AST/Stmt.h"
 #include <tuple>
+#include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h"
 
 namespace clang {
 
@@ -42,6 +43,12 @@
 std::pair<const clang::VarDecl *, const clang::Expr *>
 parseAssignment(const Stmt *S);
 
+bool isExprResultConformsComparisonRule(CheckerContext &C,
+                                        BinaryOperatorKind BOK,
+                                        const Expr *LExpr, const SVal RVal);
+bool isGreaterEqual(CheckerContext &C, const Expr *E, unsigned long long Val);
+bool isNegative(CheckerContext &C, const Expr *E);
+
 } // end GR namespace
 
 } // end clang namespace
Index: lib/StaticAnalyzer/Checkers/ConversionChecker.cpp
===================================================================
--- lib/StaticAnalyzer/Checkers/ConversionChecker.cpp
+++ lib/StaticAnalyzer/Checkers/ConversionChecker.cpp
@@ -28,6 +28,7 @@
 #include "clang/StaticAnalyzer/Core/Checker.h"
 #include "clang/StaticAnalyzer/Core/CheckerManager.h"
 #include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h"
+#include "clang/StaticAnalyzer/Core/PathSensitive/CheckerHelpers.h"
 
 using namespace clang;
 using namespace ento;
@@ -108,50 +109,6 @@
   C.emitReport(std::move(R));
 }
 
-// Is E value greater or equal than Val?
-static bool isGreaterEqual(CheckerContext &C, const Expr *E,
-                           unsigned long long Val) {
-  ProgramStateRef State = C.getState();
-  SVal EVal = C.getSVal(E);
-  if (EVal.isUnknownOrUndef() || !EVal.getAs<NonLoc>())
-    return false;
-
-  SValBuilder &Bldr = C.getSValBuilder();
-  DefinedSVal V = Bldr.makeIntVal(Val, C.getASTContext().LongLongTy);
-
-  // Is DefinedEVal greater or equal with V?
-  SVal GE = Bldr.evalBinOp(State, BO_GE, EVal, V, Bldr.getConditionType());
-  if (GE.isUnknownOrUndef())
-    return false;
-  ConstraintManager &CM = C.getConstraintManager();
-  ProgramStateRef StGE, StLT;
-  std::tie(StGE, StLT) = CM.assumeDual(State, GE.castAs<DefinedSVal>());
-  return StGE && !StLT;
-}
-
-// Is E value negative?
-static bool isNegative(CheckerContext &C, const Expr *E) {
-  ProgramStateRef State = C.getState();
-  SVal EVal = State->getSVal(E, C.getLocationContext());
-  if (EVal.isUnknownOrUndef() || !EVal.getAs<NonLoc>())
-    return false;
-  DefinedSVal DefinedEVal = EVal.castAs<DefinedSVal>();
-
-  SValBuilder &Bldr = C.getSValBuilder();
-  DefinedSVal V = Bldr.makeIntVal(0, false);
-
-  SVal LT =
-      Bldr.evalBinOp(State, BO_LT, DefinedEVal, V, Bldr.getConditionType());
-
-  // Is E value greater than MaxVal?
-  ConstraintManager &CM = C.getConstraintManager();
-  ProgramStateRef StNegative, StPositive;
-  std::tie(StNegative, StPositive) =
-      CM.assumeDual(State, LT.castAs<DefinedSVal>());
-
-  return StNegative && !StPositive;
-}
-
 bool ConversionChecker::isLossOfPrecision(const ImplicitCastExpr *Cast,
                                         CheckerContext &C) const {
   // Don't warn about explicit loss of precision.
Index: lib/StaticAnalyzer/Checkers/UndefResultChecker.cpp
===================================================================
--- lib/StaticAnalyzer/Checkers/UndefResultChecker.cpp
+++ lib/StaticAnalyzer/Checkers/UndefResultChecker.cpp
@@ -17,6 +17,7 @@
 #include "clang/StaticAnalyzer/Core/Checker.h"
 #include "clang/StaticAnalyzer/Core/CheckerManager.h"
 #include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h"
+#include "clang/StaticAnalyzer/Core/PathSensitive/CheckerHelpers.h"
 #include "clang/StaticAnalyzer/Core/PathSensitive/ExprEngine.h"
 #include "llvm/ADT/SmallString.h"
 #include "llvm/Support/raw_ostream.h"
@@ -35,6 +36,11 @@
 };
 } // end anonymous namespace
 
+bool isShiftOverflow(CheckerContext &C, const BinaryOperator *B) {
+  return isGreaterEqual(C, B->getRHS(),
+                        C.getASTContext().getIntWidth(B->getLHS()->getType()));
+}
+
 void UndefResultChecker::checkPostStmt(const BinaryOperator *B,
                                        CheckerContext &C) const {
   ProgramStateRef state = C.getState();
@@ -80,9 +86,24 @@
     }
     else {
       // Neither operand was undefined, but the result is undefined.
-      OS << "The result of the '"
-         << BinaryOperator::getOpcodeStr(B->getOpcode())
-         << "' expression is undefined";
+      if ((B->getOpcode() == BinaryOperatorKind::BO_Shl ||
+           B->getOpcode() == BinaryOperatorKind::BO_Shr) &&
+          isNegative(C, B->getRHS())) {
+        OS << "The result of the '"
+           << BinaryOperator::getOpcodeStr(B->getOpcode())
+           << "' expression is undefined due to negative value on the right "
+              "side of operand";
+      } else if ((B->getOpcode() == BinaryOperatorKind::BO_Shl ||
+                  B->getOpcode() == BinaryOperatorKind::BO_Shr) &&
+                 isShiftOverflow(C, B)) {
+        OS << "The result of the '"
+           << BinaryOperator::getOpcodeStr(B->getOpcode())
+           << "' expression is undefined due to shift count >= width of type";
+      } else {
+        OS << "The result of the '"
+           << BinaryOperator::getOpcodeStr(B->getOpcode())
+           << "' expression is undefined";
+      }
     }
     auto report = llvm::make_unique<BugReport>(*BT, OS.str(), N);
     if (Ex) {
Index: lib/StaticAnalyzer/Core/CheckerHelpers.cpp
===================================================================
--- lib/StaticAnalyzer/Core/CheckerHelpers.cpp
+++ lib/StaticAnalyzer/Core/CheckerHelpers.cpp
@@ -94,3 +94,37 @@
 
   return std::make_pair(VD, RHS);
 }
+
+bool clang::ento::isExprResultConformsComparisonRule(CheckerContext &C,
+                                                     BinaryOperatorKind BOK,
+                                                     const Expr *LExpr,
+                                                     const SVal RVal) {
+  ProgramStateRef State = C.getState();
+
+  SVal LVal = C.getSVal(LExpr);
+  if (LVal.isUnknownOrUndef() || !LVal.getAs<NonLoc>())
+    return false;
+
+  SValBuilder &Bldr = C.getSValBuilder();
+  SVal Eval = Bldr.evalBinOp(State, BOK, LVal, RVal, Bldr.getConditionType());
+  if (Eval.isUnknownOrUndef())
+    return false;
+
+  ConstraintManager &CM = C.getConstraintManager();
+  ProgramStateRef StTrue, StFalse;
+  std::tie(StTrue, StFalse) = CM.assumeDual(State, Eval.castAs<DefinedSVal>());
+  return StTrue && !StFalse;
+}
+
+// Is E value greater or equal than Val?
+bool clang::ento::isGreaterEqual(CheckerContext &C, const Expr *E,
+                                 unsigned long long Val) {
+  DefinedSVal V = C.getSValBuilder().makeIntVal(Val, C.getASTContext().LongLongTy);
+  return isExprResultConformsComparisonRule(C, BO_GE, E, V);
+}
+
+// Is E value negative?
+bool clang::ento::isNegative(CheckerContext &C, const Expr *E) {
+  DefinedSVal V = C.getSValBuilder().makeIntVal(0, false);
+  return isExprResultConformsComparisonRule(C, BO_LT, E, V);
+}
Index: test/Analysis/bitwise-ops.c
===================================================================
--- test/Analysis/bitwise-ops.c
+++ test/Analysis/bitwise-ops.c
@@ -29,4 +29,18 @@
   default:
     return 0;
   }
-}
\ No newline at end of file
+}
+
+int testOverflowShift(int a) {
+  if (a == 323) {
+    return 1 << a; // expected-warning{{The result of the '<<' expression is undefined due to shift count >= width of type}}
+  }
+  return 0;
+}
+
+int testNegativeShift(int a) {
+  if (a == -5) {
+    return 1 << a; // expected-warning{{The result of the '<<' expression is undefined due to negative value on the right side of operand}}
+  }
+  return 0;
+}