Index: include/llvm/IR/ConstantRange.h
===================================================================
--- include/llvm/IR/ConstantRange.h
+++ include/llvm/IR/ConstantRange.h
@@ -69,6 +69,14 @@
   static ConstantRange makeICmpRegion(unsigned Pred,
                                       const ConstantRange &Other);
 
+  /// Produce the range that contains exactly all the values that might satisfy
+  /// the comparison specified by Pred when compared to Other.  This is similar
+  /// to makeICmpRegion except for the additional exactness constraint -- the
+  /// resultant range does not contain any value that for which the predicate is
+  /// false.
+  ///
+  static ConstantRange makeExactICmpRegion(unsigned Pred, const APInt &Other);
+
   /// Return the lower value for this range.
   ///
   const APInt &getLower() const { return Lower; }
Index: lib/IR/ConstantRange.cpp
===================================================================
--- lib/IR/ConstantRange.cpp
+++ lib/IR/ConstantRange.cpp
@@ -114,6 +114,59 @@
   }
 }
 
+ConstantRange ConstantRange::makeExactICmpRegion(unsigned Pred,
+                                                 const APInt &AI) {
+  uint32_t W = AI.getBitWidth();
+  switch (Pred) {
+  default:
+    llvm_unreachable("Invalid ICmp predicate to makeICmpRegion()");
+  case CmpInst::ICMP_EQ:
+    return ConstantRange(AI);
+  case CmpInst::ICMP_NE:
+    return ConstantRange(AI + 1, AI);
+  case CmpInst::ICMP_ULT: {
+    if (AI.isMinValue())
+      return ConstantRange(W, /* isFullSet = */ false);
+    return ConstantRange(APInt::getMinValue(W), AI);
+  }
+  case CmpInst::ICMP_SLT: {
+    if (AI.isMinSignedValue())
+      return ConstantRange(W, /* isFullSet = */ false);
+    return ConstantRange(APInt::getSignedMinValue(W), AI);
+  }
+  case CmpInst::ICMP_ULE: {
+    if (AI.isMaxValue())
+      return ConstantRange(W);
+    return ConstantRange(APInt::getMinValue(W), AI + 1);
+  }
+  case CmpInst::ICMP_SLE: {
+    if (AI.isMaxSignedValue())
+      return ConstantRange(W);
+    return ConstantRange(APInt::getSignedMinValue(W), AI + 1);
+  }
+  case CmpInst::ICMP_UGT: {
+    if (AI.isMaxValue())
+      return ConstantRange(W, /* isFullSet = */ false);
+    return ConstantRange(AI + 1, APInt::getNullValue(W));
+  }
+  case CmpInst::ICMP_SGT: {
+    if (AI.isMaxSignedValue())
+      return ConstantRange(W, /* isFullSet = */ false);
+    return ConstantRange(AI + 1, APInt::getSignedMinValue(W));
+  }
+  case CmpInst::ICMP_UGE: {
+    if (AI.isMinValue())
+      return ConstantRange(W);
+    return ConstantRange(AI, APInt::getNullValue(W));
+  }
+  case CmpInst::ICMP_SGE: {
+    if (AI.isMinSignedValue())
+      return ConstantRange(W);
+    return ConstantRange(AI, APInt::getSignedMinValue(W));
+  }
+  }
+}
+
 /// isFullSet - Return true if this set contains all of the elements possible
 /// for this data-type
 bool ConstantRange::isFullSet() const {
Index: unittests/IR/ConstantRangeTest.cpp
===================================================================
--- unittests/IR/ConstantRangeTest.cpp
+++ unittests/IR/ConstantRangeTest.cpp
@@ -516,4 +516,24 @@
                                             SMax).isEmptySet());
 }
 
+TEST(ConstantRange, MakeICmpRegionExact) {
+  EXPECT_TRUE(ConstantRange::makeExactICmpRegion(ICmpInst::ICMP_SGT,
+                                                 APInt::getSignedMaxValue(2))
+                  .isEmptySet());
+  EXPECT_TRUE(ConstantRange::makeExactICmpRegion(
+                  ICmpInst::ICMP_SGE, APInt::getSignedMinValue(2)).isFullSet());
+  EXPECT_EQ(ConstantRange::makeExactICmpRegion(
+                ICmpInst::ICMP_ULT, APInt::getSignedMinValue(2)).getSetSize(),
+            2);
+  EXPECT_EQ(ConstantRange::makeExactICmpRegion(
+                ICmpInst::ICMP_UGT, APInt::getSignedMinValue(2)).getSetSize(),
+            1);
+  EXPECT_EQ(ConstantRange::makeExactICmpRegion(
+                ICmpInst::ICMP_NE, APInt::getMinValue(2)).getSetSize(),
+            3);
+  EXPECT_EQ(ConstantRange::makeExactICmpRegion(
+                ICmpInst::ICMP_EQ, APInt::getMinValue(2)).getSetSize(),
+            1);
+}
+
 }  // anonymous namespace