diff --git a/llvm/test/Transforms/InstCombine/known-bits.ll b/llvm/test/Transforms/InstCombine/known-bits.ll
index cb404c0b7f889f..c00bdb78709539 100644
--- a/llvm/test/Transforms/InstCombine/known-bits.ll
+++ b/llvm/test/Transforms/InstCombine/known-bits.ll
@@ -1698,5 +1698,281 @@ define i32 @test_none(float nofpclass(all) %x) {
   ret i32 %and
 }
 
+define i8 @test_icmp_add(i8 %n, i8 %n2, i8 %other) {
+; CHECK-LABEL: @test_icmp_add(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[N_ADD:%.*]] = add nuw i8 [[N:%.*]], [[N2:%.*]]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i8 [[N_ADD]], 32
+; CHECK-NEXT:    br i1 [[CMP]], label [[IF_THEN:%.*]], label [[IF_ELSE:%.*]]
+; CHECK:       if.then:
+; CHECK-NEXT:    [[R:%.*]] = and i8 [[N]], 32
+; CHECK-NEXT:    ret i8 [[R]]
+; CHECK:       if.else:
+; CHECK-NEXT:    ret i8 [[OTHER:%.*]]
+;
+entry:
+  %n_add = add nuw i8 %n, %n2
+  %cmp = icmp ult i8 %n_add, 32
+  br i1 %cmp, label %if.then, label %if.else
+
+if.then:
+  %r = and i8 %n, 32
+  ret i8 %r
+
+if.else:
+  ret i8 %other
+}
+
+define i8 @test_icmp_add_fail_nsw(i8 %n, i8 %n2, i8 %other) {
+; CHECK-LABEL: @test_icmp_add_fail_nsw(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[N_ADD:%.*]] = add nsw i8 [[N:%.*]], [[N2:%.*]]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i8 [[N_ADD]], 32
+; CHECK-NEXT:    br i1 [[CMP]], label [[IF_THEN:%.*]], label [[IF_ELSE:%.*]]
+; CHECK:       if.then:
+; CHECK-NEXT:    [[R:%.*]] = and i8 [[N]], 32
+; CHECK-NEXT:    ret i8 [[R]]
+; CHECK:       if.else:
+; CHECK-NEXT:    ret i8 [[OTHER:%.*]]
+;
+entry:
+  %n_add = add nsw i8 %n, %n2
+  %cmp = icmp ult i8 %n_add, 32
+  br i1 %cmp, label %if.then, label %if.else
+
+if.then:
+  %r = and i8 %n, 32
+  ret i8 %r
+
+if.else:
+  ret i8 %other
+}
+
+define i8 @test_icmp_add2(i8 %n, i8 %n2, i8 %other) {
+; CHECK-LABEL: @test_icmp_add2(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[N_ADD:%.*]] = add nuw nsw i8 [[N:%.*]], [[N2:%.*]]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ugt i8 [[N_ADD]], 14
+; CHECK-NEXT:    br i1 [[CMP]], label [[IF_THEN:%.*]], label [[IF_ELSE:%.*]]
+; CHECK:       if.then:
+; CHECK-NEXT:    ret i8 [[OTHER:%.*]]
+; CHECK:       if.else:
+; CHECK-NEXT:    [[R:%.*]] = and i8 [[N]], 32
+; CHECK-NEXT:    ret i8 [[R]]
+;
+entry:
+  %n_add = add nsw nuw i8 %n, %n2
+  %cmp = icmp uge i8 %n_add, 15
+  br i1 %cmp, label %if.then, label %if.else
+
+if.then:
+  ret i8 %other
+if.else:
+  %r = and i8 %n, 32
+  ret i8 %r
+
+}
+
+define i8 @test_icmp_add_fail_bad_range(i8 %n, i8 %n2, i8 %other) {
+; CHECK-LABEL: @test_icmp_add_fail_bad_range(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[N_ADD:%.*]] = add nuw i8 [[N:%.*]], [[N2:%.*]]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i8 [[N_ADD]], 33
+; CHECK-NEXT:    br i1 [[CMP]], label [[IF_THEN:%.*]], label [[IF_ELSE:%.*]]
+; CHECK:       if.then:
+; CHECK-NEXT:    [[R:%.*]] = and i8 [[N]], 32
+; CHECK-NEXT:    ret i8 [[R]]
+; CHECK:       if.else:
+; CHECK-NEXT:    ret i8 [[OTHER:%.*]]
+;
+entry:
+  %n_add = add nuw i8 %n, %n2
+  %cmp = icmp ule i8 %n_add, 32
+  br i1 %cmp, label %if.then, label %if.else
+
+if.then:
+  %r = and i8 %n, 32
+  ret i8 %r
+
+if.else:
+  ret i8 %other
+}
+
+define i8 @test_icmp_add_fail_bad_pred(i8 %n, i8 %n2, i8 %other) {
+; CHECK-LABEL: @test_icmp_add_fail_bad_pred(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[N_ADD:%.*]] = add nuw i8 [[N:%.*]], [[N2:%.*]]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ugt i8 [[N_ADD]], 32
+; CHECK-NEXT:    br i1 [[CMP]], label [[IF_THEN:%.*]], label [[IF_ELSE:%.*]]
+; CHECK:       if.then:
+; CHECK-NEXT:    [[R:%.*]] = and i8 [[N]], 32
+; CHECK-NEXT:    ret i8 [[R]]
+; CHECK:       if.else:
+; CHECK-NEXT:    ret i8 [[OTHER:%.*]]
+;
+entry:
+  %n_add = add nuw i8 %n, %n2
+  %cmp = icmp ugt i8 %n_add, 32
+  br i1 %cmp, label %if.then, label %if.else
+
+if.then:
+  %r = and i8 %n, 32
+  ret i8 %r
+
+if.else:
+  ret i8 %other
+}
+
+define i8 @test_icmp_sub(i8 %n, i8 %n2, i8 %other) {
+; CHECK-LABEL: @test_icmp_sub(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[N_SUB:%.*]] = sub nuw i8 [[N:%.*]], [[N2:%.*]]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ugt i8 [[N_SUB]], -33
+; CHECK-NEXT:    br i1 [[CMP]], label [[IF_THEN:%.*]], label [[IF_ELSE:%.*]]
+; CHECK:       if.then:
+; CHECK-NEXT:    [[R:%.*]] = and i8 [[N]], 32
+; CHECK-NEXT:    ret i8 [[R]]
+; CHECK:       if.else:
+; CHECK-NEXT:    ret i8 [[OTHER:%.*]]
+;
+entry:
+  %n_sub = sub nuw i8 %n, %n2
+  %cmp = icmp ugt i8 %n_sub, 223
+  br i1 %cmp, label %if.then, label %if.else
+
+if.then:
+  %r = and i8 %n, 32
+  ret i8 %r
+
+if.else:
+  ret i8 %other
+}
+
+define i8 @test_icmp_sub_fail_wrong_arg(i8 %n, i8 %n2, i8 %other) {
+; CHECK-LABEL: @test_icmp_sub_fail_wrong_arg(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[N_SUB:%.*]] = sub nuw i8 [[N:%.*]], [[N2:%.*]]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ugt i8 [[N_SUB]], -33
+; CHECK-NEXT:    br i1 [[CMP]], label [[IF_THEN:%.*]], label [[IF_ELSE:%.*]]
+; CHECK:       if.then:
+; CHECK-NEXT:    [[R:%.*]] = and i8 [[N2]], 32
+; CHECK-NEXT:    ret i8 [[R]]
+; CHECK:       if.else:
+; CHECK-NEXT:    ret i8 [[OTHER:%.*]]
+;
+entry:
+  %n_sub = sub nuw i8 %n, %n2
+  %cmp = icmp ugt i8 %n_sub, 223
+  br i1 %cmp, label %if.then, label %if.else
+
+if.then:
+  %r = and i8 %n2, 32
+  ret i8 %r
+
+if.else:
+  ret i8 %other
+}
+
+define i8 @test_icmp_sub2(i8 %n, i8 %n2, i8 %other) {
+; CHECK-LABEL: @test_icmp_sub2(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[N_SUB:%.*]] = sub nuw i8 [[N:%.*]], [[N2:%.*]]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i8 [[N_SUB]], -31
+; CHECK-NEXT:    br i1 [[CMP]], label [[IF_THEN:%.*]], label [[IF_ELSE:%.*]]
+; CHECK:       if.then:
+; CHECK-NEXT:    ret i8 [[OTHER:%.*]]
+; CHECK:       if.else:
+; CHECK-NEXT:    [[R:%.*]] = and i8 [[N]], 32
+; CHECK-NEXT:    ret i8 [[R]]
+;
+entry:
+  %n_sub = sub nuw i8 %n, %n2
+  %cmp = icmp ule i8 %n_sub, 224
+  br i1 %cmp, label %if.then, label %if.else
+
+if.then:
+  ret i8 %other
+if.else:
+  %r = and i8 %n, 32
+  ret i8 %r
+
+}
+
+define i8 @test_icmp_sub2_fail_nsw(i8 %n, i8 %n2, i8 %other) {
+; CHECK-LABEL: @test_icmp_sub2_fail_nsw(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[N_SUB:%.*]] = sub nsw i8 [[N:%.*]], [[N2:%.*]]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i8 [[N_SUB]], -31
+; CHECK-NEXT:    br i1 [[CMP]], label [[IF_THEN:%.*]], label [[IF_ELSE:%.*]]
+; CHECK:       if.then:
+; CHECK-NEXT:    ret i8 [[OTHER:%.*]]
+; CHECK:       if.else:
+; CHECK-NEXT:    [[R:%.*]] = and i8 [[N]], 32
+; CHECK-NEXT:    ret i8 [[R]]
+;
+entry:
+  %n_sub = sub nsw i8 %n, %n2
+  %cmp = icmp ule i8 %n_sub, 224
+  br i1 %cmp, label %if.then, label %if.else
+
+if.then:
+  ret i8 %other
+if.else:
+  %r = and i8 %n, 32
+  ret i8 %r
+
+}
+
+
+define i8 @test_icmp_sub_fail_bad_range(i8 %n, i8 %n2, i8 %other) {
+; CHECK-LABEL: @test_icmp_sub_fail_bad_range(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[N_SUB:%.*]] = sub nuw i8 [[N:%.*]], [[N2:%.*]]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ugt i8 [[N_SUB]], -34
+; CHECK-NEXT:    br i1 [[CMP]], label [[IF_THEN:%.*]], label [[IF_ELSE:%.*]]
+; CHECK:       if.then:
+; CHECK-NEXT:    [[R:%.*]] = and i8 [[N]], 32
+; CHECK-NEXT:    ret i8 [[R]]
+; CHECK:       if.else:
+; CHECK-NEXT:    ret i8 [[OTHER:%.*]]
+;
+entry:
+  %n_sub = sub nuw i8 %n, %n2
+  %cmp = icmp uge i8 %n_sub, 223
+  br i1 %cmp, label %if.then, label %if.else
+
+if.then:
+  %r = and i8 %n, 32
+  ret i8 %r
+
+if.else:
+  ret i8 %other
+}
+
+define i8 @test_icmp_sub_fail_bad_pred(i8 %n, i8 %n2, i8 %other) {
+; CHECK-LABEL: @test_icmp_sub_fail_bad_pred(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[N_SUB:%.*]] = sub nuw i8 [[N:%.*]], [[N2:%.*]]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i8 [[N_SUB]], 31
+; CHECK-NEXT:    br i1 [[CMP]], label [[IF_THEN:%.*]], label [[IF_ELSE:%.*]]
+; CHECK:       if.then:
+; CHECK-NEXT:    [[R:%.*]] = and i8 [[N]], 32
+; CHECK-NEXT:    ret i8 [[R]]
+; CHECK:       if.else:
+; CHECK-NEXT:    ret i8 [[OTHER:%.*]]
+;
+entry:
+  %n_sub = sub nuw i8 %n, %n2
+  %cmp = icmp sge i8 %n_sub, 32
+  br i1 %cmp, label %if.then, label %if.else
+
+if.then:
+  %r = and i8 %n, 32
+  ret i8 %r
+
+if.else:
+  ret i8 %other
+}
+
 declare void @use(i1)
 declare void @sink(i8)