--- /dev/null
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt < %s -instsimplify -S | FileCheck %s
+
+define i32 @negate_nuw(i32 %x) {
+; CHECK-LABEL: @negate_nuw(
+; CHECK-NEXT: ret i32 0
+;
+ %neg = sub nuw i32 0, %x
+ ret i32 %neg
+}
+
+define <2 x i32> @negate_nuw_vec(<2 x i32> %x) {
+; CHECK-LABEL: @negate_nuw_vec(
+; CHECK-NEXT: ret <2 x i32> zeroinitializer
+;
+ %neg = sub nuw <2 x i32> zeroinitializer, %x
+ ret <2 x i32> %neg
+}
+
+define i8 @negate_zero_or_minsigned_nsw(i8 %x) {
+; CHECK-LABEL: @negate_zero_or_minsigned_nsw(
+; CHECK-NEXT: [[SIGNBIT:%.*]] = and i8 %x, -128
+; CHECK-NEXT: [[NEG:%.*]] = sub nsw i8 0, [[SIGNBIT]]
+; CHECK-NEXT: ret i8 [[NEG]]
+;
+ %signbit = and i8 %x, 128
+ %neg = sub nsw i8 0, %signbit
+ ret i8 %neg
+}
+
+define <2 x i8> @negate_zero_or_minsigned_nsw_vec(<2 x i8> %x) {
+; CHECK-LABEL: @negate_zero_or_minsigned_nsw_vec(
+; CHECK-NEXT: [[SIGNBIT:%.*]] = shl <2 x i8> %x, <i8 7, i8 7>
+; CHECK-NEXT: [[NEG:%.*]] = sub nsw <2 x i8> zeroinitializer, [[SIGNBIT]]
+; CHECK-NEXT: ret <2 x i8> [[NEG]]
+;
+ %signbit = shl <2 x i8> %x, <i8 7, i8 7>
+ %neg = sub nsw <2 x i8> zeroinitializer, %signbit
+ ret <2 x i8> %neg
+}
+
+define i8 @negate_zero_or_minsigned(i8 %x) {
+; CHECK-LABEL: @negate_zero_or_minsigned(
+; CHECK-NEXT: [[SIGNBIT:%.*]] = shl i8 %x, 7
+; CHECK-NEXT: [[NEG:%.*]] = sub i8 0, [[SIGNBIT]]
+; CHECK-NEXT: ret i8 [[NEG]]
+;
+ %signbit = shl i8 %x, 7
+ %neg = sub i8 0, %signbit
+ ret i8 %neg
+}
+
+define <2 x i8> @negate_zero_or_minsigned_vec(<2 x i8> %x) {
+; CHECK-LABEL: @negate_zero_or_minsigned_vec(
+; CHECK-NEXT: [[SIGNBIT:%.*]] = and <2 x i8> %x, <i8 -128, i8 -128>
+; CHECK-NEXT: [[NEG:%.*]] = sub <2 x i8> zeroinitializer, [[SIGNBIT]]
+; CHECK-NEXT: ret <2 x i8> [[NEG]]
+;
+ %signbit = and <2 x i8> %x, <i8 128, i8 128>
+ %neg = sub <2 x i8> zeroinitializer, %signbit
+ ret <2 x i8> %neg
+}
+