diff --git a/llvm/lib/Transforms/Scalar/ConstraintElimination.cpp b/llvm/lib/Transforms/Scalar/ConstraintElimination.cpp
--- a/llvm/lib/Transforms/Scalar/ConstraintElimination.cpp
+++ b/llvm/lib/Transforms/Scalar/ConstraintElimination.cpp
@@ -55,6 +55,10 @@
   ConstantInt *CI;
   if (match(V, m_NUWAdd(m_Value(Op0), m_ConstantInt(CI))))
     return {{CI->getSExtValue(), Op0}};
+
+  if (match(V, m_NUWSub(m_Value(Op0), m_ConstantInt(CI))))
+    return {{-1 * CI->getSExtValue(), Op0}};
+
   return {{0, V}};
 }
 
diff --git a/llvm/test/Transforms/ConstraintElimination/sub-nuw.ll b/llvm/test/Transforms/ConstraintElimination/sub-nuw.ll
--- a/llvm/test/Transforms/ConstraintElimination/sub-nuw.ll
+++ b/llvm/test/Transforms/ConstraintElimination/sub-nuw.ll
@@ -20,10 +20,10 @@
 ; CHECK-NEXT:    call void @use(i1 [[T_2]])
 ; CHECK-NEXT:    [[START_3:%.*]] = sub nuw i8 [[START]], 3
 ; CHECK-NEXT:    [[T_3:%.*]] = icmp ult i8 [[START_3]], [[HIGH]]
-; CHECK-NEXT:    call void @use(i1 [[T_3]])
+; CHECK-NEXT:    call void @use(i1 true)
 ; CHECK-NEXT:    [[START_4:%.*]] = sub nuw i8 [[START]], 4
 ; CHECK-NEXT:    [[C_4:%.*]] = icmp ult i8 [[START_4]], [[HIGH]]
-; CHECK-NEXT:    call void @use(i1 [[C_4]])
+; CHECK-NEXT:    call void @use(i1 true)
 ; CHECK-NEXT:    ret void
 ;
 entry:
@@ -68,16 +68,16 @@
 ; CHECK-NEXT:    call void @use(i1 [[T_1]])
 ; CHECK-NEXT:    [[START_2:%.*]] = sub nuw i8 [[START]], 2
 ; CHECK-NEXT:    [[T_2:%.*]] = icmp ule i8 [[START_2]], [[HIGH]]
-; CHECK-NEXT:    call void @use(i1 [[T_2]])
+; CHECK-NEXT:    call void @use(i1 true)
 ; CHECK-NEXT:    [[START_3:%.*]] = sub nuw i8 [[START]], 3
 ; CHECK-NEXT:    [[T_3:%.*]] = icmp ule i8 [[START_3]], [[HIGH]]
-; CHECK-NEXT:    call void @use(i1 [[T_3]])
+; CHECK-NEXT:    call void @use(i1 true)
 ; CHECK-NEXT:    [[START_4:%.*]] = sub nuw i8 [[START]], 4
 ; CHECK-NEXT:    [[T_4:%.*]] = icmp ule i8 [[START_4]], [[HIGH]]
-; CHECK-NEXT:    call void @use(i1 [[T_4]])
+; CHECK-NEXT:    call void @use(i1 true)
 ; CHECK-NEXT:    [[START_5:%.*]] = sub nuw i8 [[START]], 5
 ; CHECK-NEXT:    [[C_5:%.*]] = icmp ule i8 [[START_5]], [[HIGH]]
-; CHECK-NEXT:    call void @use(i1 [[C_5]])
+; CHECK-NEXT:    call void @use(i1 true)
 ; CHECK-NEXT:    ret void
 ;
 entry:
@@ -127,16 +127,16 @@
 ; CHECK-NEXT:    call void @use(i1 [[F_1]])
 ; CHECK-NEXT:    [[START_2:%.*]] = sub nuw i8 [[START]], 2
 ; CHECK-NEXT:    [[F_2:%.*]] = icmp ugt i8 [[START_2]], [[HIGH]]
-; CHECK-NEXT:    call void @use(i1 [[F_2]])
+; CHECK-NEXT:    call void @use(i1 false)
 ; CHECK-NEXT:    [[START_3:%.*]] = sub nuw i8 [[START]], 3
 ; CHECK-NEXT:    [[F_3:%.*]] = icmp ugt i8 [[START_3]], [[HIGH]]
-; CHECK-NEXT:    call void @use(i1 [[F_3]])
+; CHECK-NEXT:    call void @use(i1 false)
 ; CHECK-NEXT:    [[START_4:%.*]] = sub nuw i8 [[START]], 4
 ; CHECK-NEXT:    [[F_4:%.*]] = icmp ugt i8 [[START_4]], [[HIGH]]
-; CHECK-NEXT:    call void @use(i1 [[F_4]])
+; CHECK-NEXT:    call void @use(i1 false)
 ; CHECK-NEXT:    [[START_5:%.*]] = sub nuw i8 [[START]], 5
 ; CHECK-NEXT:    [[C_5:%.*]] = icmp ugt i8 [[START_5]], [[HIGH]]
-; CHECK-NEXT:    call void @use(i1 [[C_5]])
+; CHECK-NEXT:    call void @use(i1 false)
 ; CHECK-NEXT:    ret void
 ;
 entry:
@@ -193,13 +193,13 @@
 ; CHECK-NEXT:    call void @use(i1 [[F_2]])
 ; CHECK-NEXT:    [[START_3:%.*]] = sub nuw i8 [[START]], 3
 ; CHECK-NEXT:    [[F_3:%.*]] = icmp uge i8 [[START_3]], [[HIGH]]
-; CHECK-NEXT:    call void @use(i1 [[F_3]])
+; CHECK-NEXT:    call void @use(i1 false)
 ; CHECK-NEXT:    [[START_4:%.*]] = sub nuw i8 [[START]], 4
 ; CHECK-NEXT:    [[C_4:%.*]] = icmp uge i8 [[START_4]], [[HIGH]]
-; CHECK-NEXT:    call void @use(i1 [[C_4]])
+; CHECK-NEXT:    call void @use(i1 false)
 ; CHECK-NEXT:    [[START_5:%.*]] = sub nuw i8 [[START]], 5
 ; CHECK-NEXT:    [[C_5:%.*]] = icmp uge i8 [[START_5]], [[HIGH]]
-; CHECK-NEXT:    call void @use(i1 [[C_5]])
+; CHECK-NEXT:    call void @use(i1 false)
 ; CHECK-NEXT:    ret void
 ;
 entry: