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
@@ -688,6 +688,15 @@
       return;
     replaceSubOverflowUses(II, A, B, ToRemove);
   }
+  if (II->getIntrinsicID() == Intrinsic::usub_with_overflow) {
+    // if A >= B usub_with_overflow(a, b) should not overflow and
+    // can be simplified to a regular sub
+    Value *A = II->getArgOperand(0);
+    Value *B = II->getArgOperand(1);
+    if (!DoesConditionHold(CmpInst::ICMP_UGE, A, B, Info))
+      return;
+    replaceSubOverflowUses(II, A, B, ToRemove);
+  }
 }
 
 static bool eliminateConstraints(Function &F, DominatorTree &DT) {
diff --git a/llvm/test/Transforms/ConstraintElimination/usub-with-overflow.ll b/llvm/test/Transforms/ConstraintElimination/usub-with-overflow.ll
--- a/llvm/test/Transforms/ConstraintElimination/usub-with-overflow.ll
+++ b/llvm/test/Transforms/ConstraintElimination/usub-with-overflow.ll
@@ -9,12 +9,10 @@
 ; CHECK-NEXT:    [[C_1:%.*]] = icmp uge i8 [[B:%.*]], [[A:%.*]]
 ; CHECK-NEXT:    br i1 [[C_1]], label [[MATH:%.*]], label [[EXIT_FAIL:%.*]]
 ; CHECK:       math:
-; CHECK-NEXT:    [[OP:%.*]] = tail call { i8, i1 } @llvm.usub.with.overflow.i8(i8 [[B]], i8 [[A]])
-; CHECK-NEXT:    [[STATUS:%.*]] = extractvalue { i8, i1 } [[OP]], 1
-; CHECK-NEXT:    br i1 [[STATUS]], label [[EXIT_FAIL]], label [[EXIT_OK:%.*]]
+; CHECK-NEXT:    [[TMP0:%.*]] = sub i8 [[B]], [[A]]
+; CHECK-NEXT:    br i1 false, label [[EXIT_FAIL]], label [[EXIT_OK:%.*]]
 ; CHECK:       exit.ok:
-; CHECK-NEXT:    [[RES:%.*]] = extractvalue { i8, i1 } [[OP]], 0
-; CHECK-NEXT:    ret i8 [[RES]]
+; CHECK-NEXT:    ret i8 [[TMP0]]
 ; CHECK:       exit.fail:
 ; CHECK-NEXT:    ret i8 0
 ;
@@ -41,12 +39,10 @@
 ; CHECK-NEXT:    [[C_1:%.*]] = icmp ule i8 [[B:%.*]], [[A:%.*]]
 ; CHECK-NEXT:    br i1 [[C_1]], label [[EXIT_FAIL:%.*]], label [[MATH:%.*]]
 ; CHECK:       math:
-; CHECK-NEXT:    [[OP:%.*]] = tail call { i8, i1 } @llvm.usub.with.overflow.i8(i8 [[B]], i8 [[A]])
-; CHECK-NEXT:    [[STATUS:%.*]] = extractvalue { i8, i1 } [[OP]], 1
-; CHECK-NEXT:    br i1 [[STATUS]], label [[EXIT_FAIL]], label [[EXIT_OK:%.*]]
+; CHECK-NEXT:    [[TMP0:%.*]] = sub i8 [[B]], [[A]]
+; CHECK-NEXT:    br i1 false, label [[EXIT_FAIL]], label [[EXIT_OK:%.*]]
 ; CHECK:       exit.ok:
-; CHECK-NEXT:    [[RES:%.*]] = extractvalue { i8, i1 } [[OP]], 0
-; CHECK-NEXT:    ret i8 [[RES]]
+; CHECK-NEXT:    ret i8 [[TMP0]]
 ; CHECK:       exit.fail:
 ; CHECK-NEXT:    ret i8 0
 ;
@@ -75,13 +71,12 @@
 ; CHECK-NEXT:    [[C_1:%.*]] = icmp ule i8 [[B:%.*]], [[A:%.*]]
 ; CHECK-NEXT:    br i1 [[C_1]], label [[EXIT_FAIL:%.*]], label [[MATH:%.*]]
 ; CHECK:       math:
+; CHECK-NEXT:    [[TMP0:%.*]] = sub i8 [[B]], [[A]]
 ; CHECK-NEXT:    [[OP:%.*]] = tail call { i8, i1 } @llvm.usub.with.overflow.i8(i8 [[B]], i8 [[A]])
 ; CHECK-NEXT:    call void @use_res({ i8, i1 } [[OP]])
-; CHECK-NEXT:    [[STATUS:%.*]] = extractvalue { i8, i1 } [[OP]], 1
-; CHECK-NEXT:    br i1 [[STATUS]], label [[EXIT_FAIL]], label [[EXIT_OK:%.*]]
+; CHECK-NEXT:    br i1 false, label [[EXIT_FAIL]], label [[EXIT_OK:%.*]]
 ; CHECK:       exit.ok:
-; CHECK-NEXT:    [[RES:%.*]] = extractvalue { i8, i1 } [[OP]], 0
-; CHECK-NEXT:    ret i8 [[RES]]
+; CHECK-NEXT:    ret i8 [[TMP0]]
 ; CHECK:       exit.fail:
 ; CHECK-NEXT:    ret i8 0
 ;
@@ -111,12 +106,10 @@
 ; CHECK-NEXT:    [[OR:%.*]] = or i1 [[C_2]], [[C_1]]
 ; CHECK-NEXT:    br i1 [[OR]], label [[EXIT_FAIL:%.*]], label [[MATH:%.*]]
 ; CHECK:       math:
-; CHECK-NEXT:    [[OP:%.*]] = tail call { i8, i1 } @llvm.usub.with.overflow.i8(i8 [[B]], i8 [[A]])
-; CHECK-NEXT:    [[STATUS:%.*]] = extractvalue { i8, i1 } [[OP]], 1
-; CHECK-NEXT:    br i1 [[STATUS]], label [[EXIT_FAIL]], label [[EXIT_OK:%.*]]
+; CHECK-NEXT:    [[TMP0:%.*]] = sub i8 [[B]], [[A]]
+; CHECK-NEXT:    br i1 false, label [[EXIT_FAIL]], label [[EXIT_OK:%.*]]
 ; CHECK:       exit.ok:
-; CHECK-NEXT:    [[RES:%.*]] = extractvalue { i8, i1 } [[OP]], 0
-; CHECK-NEXT:    ret i8 [[RES]]
+; CHECK-NEXT:    ret i8 [[TMP0]]
 ; CHECK:       exit.fail:
 ; CHECK-NEXT:    ret i8 0
 ;
@@ -147,9 +140,7 @@
 ; CHECK-NEXT:    [[OR:%.*]] = or i1 [[C_2]], [[C_1]]
 ; CHECK-NEXT:    br i1 [[OR]], label [[EXIT_FAIL:%.*]], label [[MATH:%.*]]
 ; CHECK:       math:
-; CHECK-NEXT:    [[OP:%.*]] = tail call { i8, i1 } @llvm.usub.with.overflow.i8(i8 [[B]], i8 [[A]])
-; CHECK-NEXT:    [[STATUS:%.*]] = extractvalue { i8, i1 } [[OP]], 1
-; CHECK-NEXT:    br i1 [[STATUS]], label [[EXIT_FAIL]], label [[EXIT_OK:%.*]]
+; CHECK-NEXT:    br i1 false, label [[EXIT_FAIL]], label [[EXIT_OK:%.*]]
 ; CHECK:       exit.ok:
 ; CHECK-NEXT:    ret i8 20
 ; CHECK:       exit.fail:
@@ -181,12 +172,10 @@
 ; CHECK-NEXT:    [[AND:%.*]] = and i1 [[C_2]], [[C_1]]
 ; CHECK-NEXT:    br i1 [[AND]], label [[MATH:%.*]], label [[EXIT_FAIL:%.*]]
 ; CHECK:       math:
-; CHECK-NEXT:    [[OP:%.*]] = tail call { i8, i1 } @llvm.usub.with.overflow.i8(i8 [[B]], i8 [[A]])
-; CHECK-NEXT:    [[STATUS:%.*]] = extractvalue { i8, i1 } [[OP]], 1
-; CHECK-NEXT:    br i1 [[STATUS]], label [[EXIT_FAIL]], label [[EXIT_OK:%.*]]
+; CHECK-NEXT:    [[TMP0:%.*]] = sub i8 [[B]], [[A]]
+; CHECK-NEXT:    br i1 false, label [[EXIT_FAIL]], label [[EXIT_OK:%.*]]
 ; CHECK:       exit.ok:
-; CHECK-NEXT:    [[RES:%.*]] = extractvalue { i8, i1 } [[OP]], 0
-; CHECK-NEXT:    ret i8 [[RES]]
+; CHECK-NEXT:    ret i8 [[TMP0]]
 ; CHECK:       exit.fail:
 ; CHECK-NEXT:    ret i8 0
 ;