diff --git a/llvm/test/Transforms/InstCombine/canonicalize-low-bit-mask-v4-and-icmp-eq-to-icmp-ule.ll b/llvm/test/Transforms/InstCombine/canonicalize-low-bit-mask-v4-and-icmp-eq-to-icmp-ule.ll
new file mode 100644
index 000000000000..ab4b114cf436
--- /dev/null
+++ b/llvm/test/Transforms/InstCombine/canonicalize-low-bit-mask-v4-and-icmp-eq-to-icmp-ule.ll
@@ -0,0 +1,255 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt < %s -instcombine -S | FileCheck %s
+
+; https://bugs.llvm.org/show_bug.cgi?id=38123
+
+; Pattern:
+;   x & ((-1 << y) >> y) == x
+; Should be transformed into:
+;   x u<= ((-1 << y) >> y)
+
+; This pattern is uncanonical, but we can not canonicalize it due to extra uses.
+
+declare void @use8(i8)
+declare void @use2i8(<2 x i8>)
+declare void @use3i8(<3 x i8>)
+
+; ============================================================================ ;
+; Basic positive tests
+; ============================================================================ ;
+
+define i1 @p0(i8 %x, i8 %y) {
+; CHECK-LABEL: @p0(
+; CHECK-NEXT:    [[T0:%.*]] = shl i8 -1, [[Y:%.*]]
+; CHECK-NEXT:    call void @use8(i8 [[T0]])
+; CHECK-NEXT:    [[T1:%.*]] = lshr i8 [[T0]], [[Y]]
+; CHECK-NEXT:    [[T2:%.*]] = and i8 [[T1]], [[X:%.*]]
+; CHECK-NEXT:    [[RET:%.*]] = icmp eq i8 [[T2]], [[X]]
+; CHECK-NEXT:    ret i1 [[RET]]
+;
+  %t0 = shl i8 -1, %y
+  call void @use8(i8 %t0)
+  %t1 = lshr i8 %t0, %y
+  %t2 = and i8 %t1, %x
+  %ret = icmp eq i8 %t2, %x
+  ret i1 %ret
+}
+
+; ============================================================================ ;
+; Vector tests
+; ============================================================================ ;
+
+define <2 x i1> @p1_vec(<2 x i8> %x, <2 x i8> %y) {
+; CHECK-LABEL: @p1_vec(
+; CHECK-NEXT:    [[T0:%.*]] = shl <2 x i8> <i8 -1, i8 -1>, [[Y:%.*]]
+; CHECK-NEXT:    call void @use2i8(<2 x i8> [[T0]])
+; CHECK-NEXT:    [[T1:%.*]] = lshr <2 x i8> [[T0]], [[Y]]
+; CHECK-NEXT:    [[T2:%.*]] = and <2 x i8> [[T1]], [[X:%.*]]
+; CHECK-NEXT:    [[RET:%.*]] = icmp eq <2 x i8> [[T2]], [[X]]
+; CHECK-NEXT:    ret <2 x i1> [[RET]]
+;
+  %t0 = shl <2 x i8> <i8 -1, i8 -1>, %y
+  call void @use2i8(<2 x i8> %t0)
+  %t1 = lshr <2 x i8> %t0, %y
+  %t2 = and <2 x i8> %t1, %x
+  %ret = icmp eq <2 x i8> %t2, %x
+  ret <2 x i1> %ret
+}
+
+define <3 x i1> @p2_vec_undef0(<3 x i8> %x, <3 x i8> %y) {
+; CHECK-LABEL: @p2_vec_undef0(
+; CHECK-NEXT:    [[T0:%.*]] = shl <3 x i8> <i8 -1, i8 undef, i8 -1>, [[Y:%.*]]
+; CHECK-NEXT:    call void @use3i8(<3 x i8> [[T0]])
+; CHECK-NEXT:    [[T1:%.*]] = lshr <3 x i8> [[T0]], [[Y]]
+; CHECK-NEXT:    [[T2:%.*]] = and <3 x i8> [[T1]], [[X:%.*]]
+; CHECK-NEXT:    [[RET:%.*]] = icmp eq <3 x i8> [[T2]], [[X]]
+; CHECK-NEXT:    ret <3 x i1> [[RET]]
+;
+  %t0 = shl <3 x i8> <i8 -1, i8 undef, i8 -1>, %y
+  call void @use3i8(<3 x i8> %t0)
+  %t1 = lshr <3 x i8> %t0, %y
+  %t2 = and <3 x i8> %t1, %x
+  %ret = icmp eq <3 x i8> %t2, %x
+  ret <3 x i1> %ret
+}
+
+; ============================================================================ ;
+; Commutativity tests.
+; ============================================================================ ;
+
+declare i8 @gen8()
+
+define i1 @c0(i8 %y) {
+; CHECK-LABEL: @c0(
+; CHECK-NEXT:    [[T0:%.*]] = shl i8 -1, [[Y:%.*]]
+; CHECK-NEXT:    call void @use8(i8 [[T0]])
+; CHECK-NEXT:    [[T1:%.*]] = lshr i8 [[T0]], [[Y]]
+; CHECK-NEXT:    [[X:%.*]] = call i8 @gen8()
+; CHECK-NEXT:    [[T2:%.*]] = and i8 [[X]], [[T1]]
+; CHECK-NEXT:    [[RET:%.*]] = icmp eq i8 [[T2]], [[X]]
+; CHECK-NEXT:    ret i1 [[RET]]
+;
+  %t0 = shl i8 -1, %y
+  call void @use8(i8 %t0)
+  %t1 = lshr i8 %t0, %y
+  %x = call i8 @gen8()
+  %t2 = and i8 %x, %t1 ; swapped order
+  %ret = icmp eq i8 %t2, %x
+  ret i1 %ret
+}
+
+define i1 @c1(i8 %y) {
+; CHECK-LABEL: @c1(
+; CHECK-NEXT:    [[T0:%.*]] = shl i8 -1, [[Y:%.*]]
+; CHECK-NEXT:    call void @use8(i8 [[T0]])
+; CHECK-NEXT:    [[T1:%.*]] = lshr i8 [[T0]], [[Y]]
+; CHECK-NEXT:    [[X:%.*]] = call i8 @gen8()
+; CHECK-NEXT:    [[T2:%.*]] = and i8 [[T1]], [[X]]
+; CHECK-NEXT:    [[RET:%.*]] = icmp eq i8 [[X]], [[T2]]
+; CHECK-NEXT:    ret i1 [[RET]]
+;
+  %t0 = shl i8 -1, %y
+  call void @use8(i8 %t0)
+  %t1 = lshr i8 %t0, %y
+  %x = call i8 @gen8()
+  %t2 = and i8 %t1, %x
+  %ret = icmp eq i8 %x, %t2 ; swapped order
+  ret i1 %ret
+}
+
+define i1 @c2(i8 %y) {
+; CHECK-LABEL: @c2(
+; CHECK-NEXT:    [[T0:%.*]] = shl i8 -1, [[Y:%.*]]
+; CHECK-NEXT:    call void @use8(i8 [[T0]])
+; CHECK-NEXT:    [[T1:%.*]] = lshr i8 [[T0]], [[Y]]
+; CHECK-NEXT:    [[X:%.*]] = call i8 @gen8()
+; CHECK-NEXT:    [[T2:%.*]] = and i8 [[X]], [[T1]]
+; CHECK-NEXT:    [[RET:%.*]] = icmp eq i8 [[X]], [[T2]]
+; CHECK-NEXT:    ret i1 [[RET]]
+;
+  %t0 = shl i8 -1, %y
+  call void @use8(i8 %t0)
+  %t1 = lshr i8 %t0, %y
+  %x = call i8 @gen8()
+  %t2 = and i8 %x, %t1 ; swapped order
+  %ret = icmp eq i8 %x, %t2 ; swapped order
+  ret i1 %ret
+}
+
+; ============================================================================ ;
+; One-use tests. We don't care about multi-uses here.
+; ============================================================================ ;
+
+define i1 @oneuse0(i8 %x, i8 %y) {
+; CHECK-LABEL: @oneuse0(
+; CHECK-NEXT:    [[T0:%.*]] = shl i8 -1, [[Y:%.*]]
+; CHECK-NEXT:    call void @use8(i8 [[T0]])
+; CHECK-NEXT:    [[T1:%.*]] = lshr i8 [[T0]], [[Y]]
+; CHECK-NEXT:    call void @use8(i8 [[T1]])
+; CHECK-NEXT:    [[T2:%.*]] = and i8 [[T1]], [[X:%.*]]
+; CHECK-NEXT:    [[RET:%.*]] = icmp eq i8 [[T2]], [[X]]
+; CHECK-NEXT:    ret i1 [[RET]]
+;
+  %t0 = shl i8 -1, %y
+  call void @use8(i8 %t0) ; needed anyway
+  %t1 = lshr i8 %t0, %y
+  call void @use8(i8 %t1)
+  %t2 = and i8 %t1, %x
+  %ret = icmp eq i8 %t2, %x
+  ret i1 %ret
+}
+
+define i1 @oneuse1(i8 %x, i8 %y) {
+; CHECK-LABEL: @oneuse1(
+; CHECK-NEXT:    [[T0:%.*]] = shl i8 -1, [[Y:%.*]]
+; CHECK-NEXT:    call void @use8(i8 [[T0]])
+; CHECK-NEXT:    [[T1:%.*]] = lshr i8 [[T0]], [[Y]]
+; CHECK-NEXT:    [[T2:%.*]] = and i8 [[T1]], [[X:%.*]]
+; CHECK-NEXT:    call void @use8(i8 [[T2]])
+; CHECK-NEXT:    [[RET:%.*]] = icmp eq i8 [[T2]], [[X]]
+; CHECK-NEXT:    ret i1 [[RET]]
+;
+  %t0 = shl i8 -1, %y
+  call void @use8(i8 %t0) ; needed anyway
+  %t1 = lshr i8 %t0, %y
+  %t2 = and i8 %t1, %x
+  call void @use8(i8 %t2)
+  %ret = icmp eq i8 %t2, %x
+  ret i1 %ret
+}
+
+define i1 @oneuse2(i8 %x, i8 %y) {
+; CHECK-LABEL: @oneuse2(
+; CHECK-NEXT:    [[T0:%.*]] = shl i8 -1, [[Y:%.*]]
+; CHECK-NEXT:    call void @use8(i8 [[T0]])
+; CHECK-NEXT:    [[T1:%.*]] = lshr i8 [[T0]], [[Y]]
+; CHECK-NEXT:    call void @use8(i8 [[T1]])
+; CHECK-NEXT:    [[T2:%.*]] = and i8 [[T1]], [[X:%.*]]
+; CHECK-NEXT:    call void @use8(i8 [[T2]])
+; CHECK-NEXT:    [[RET:%.*]] = icmp eq i8 [[T2]], [[X]]
+; CHECK-NEXT:    ret i1 [[RET]]
+;
+  %t0 = shl i8 -1, %y
+  call void @use8(i8 %t0)
+  %t1 = lshr i8 %t0, %y
+  call void @use8(i8 %t1)
+  %t2 = and i8 %t1, %x
+  call void @use8(i8 %t2)
+  %ret = icmp eq i8 %t2, %x
+  ret i1 %ret
+}
+
+; ============================================================================ ;
+; Negative tests
+; ============================================================================ ;
+
+define i1 @n0(i8 %x, i8 %y, i8 %notx) {
+; CHECK-LABEL: @n0(
+; CHECK-NEXT:    [[T0:%.*]] = shl i8 -1, [[Y:%.*]]
+; CHECK-NEXT:    call void @use8(i8 [[T0]])
+; CHECK-NEXT:    [[T1:%.*]] = lshr i8 [[T0]], [[Y]]
+; CHECK-NEXT:    [[T2:%.*]] = and i8 [[T1]], [[X:%.*]]
+; CHECK-NEXT:    [[RET:%.*]] = icmp eq i8 [[T2]], [[NOTX:%.*]]
+; CHECK-NEXT:    ret i1 [[RET]]
+;
+  %t0 = shl i8 -1, %y
+  call void @use8(i8 %t0)
+  %t1 = lshr i8 %t0, %y
+  %t2 = and i8 %t1, %x
+  %ret = icmp eq i8 %t2, %notx ; not %x
+  ret i1 %ret
+}
+
+define i1 @n1(i8 %x, i8 %y) {
+; CHECK-LABEL: @n1(
+; CHECK-NEXT:    [[T0:%.*]] = shl i8 1, [[Y:%.*]]
+; CHECK-NEXT:    call void @use8(i8 [[T0]])
+; CHECK-NEXT:    [[T1:%.*]] = lshr i8 [[T0]], [[Y]]
+; CHECK-NEXT:    [[T2:%.*]] = and i8 [[T1]], [[X:%.*]]
+; CHECK-NEXT:    [[RET:%.*]] = icmp eq i8 [[T2]], [[X]]
+; CHECK-NEXT:    ret i1 [[RET]]
+;
+  %t0 = shl i8 1, %y ; not -1
+  call void @use8(i8 %t0)
+  %t1 = lshr i8 %t0, %y
+  %t2 = and i8 %t1, %x
+  %ret = icmp eq i8 %t2, %x
+  ret i1 %ret
+}
+
+define i1 @n2(i8 %x, i8 %y1, i8 %y2) {
+; CHECK-LABEL: @n2(
+; CHECK-NEXT:    [[T0:%.*]] = shl i8 -1, [[Y1:%.*]]
+; CHECK-NEXT:    call void @use8(i8 [[T0]])
+; CHECK-NEXT:    [[T1:%.*]] = lshr i8 [[T0]], [[Y2:%.*]]
+; CHECK-NEXT:    [[T2:%.*]] = and i8 [[T1]], [[X:%.*]]
+; CHECK-NEXT:    [[RET:%.*]] = icmp eq i8 [[T2]], [[X]]
+; CHECK-NEXT:    ret i1 [[RET]]
+;
+  %t0 = shl i8 -1, %y1 ; not %y2
+  call void @use8(i8 %t0)
+  %t1 = lshr i8 %t0, %y2 ; not %y1
+  %t2 = and i8 %t1, %x
+  %ret = icmp eq i8 %t2, %x
+  ret i1 %ret
+}
diff --git a/llvm/test/Transforms/InstCombine/canonicalize-low-bit-mask-v4-and-icmp-ne-to-icmp-ugt.ll b/llvm/test/Transforms/InstCombine/canonicalize-low-bit-mask-v4-and-icmp-ne-to-icmp-ugt.ll
new file mode 100644
index 000000000000..f6cb226cb3f0
--- /dev/null
+++ b/llvm/test/Transforms/InstCombine/canonicalize-low-bit-mask-v4-and-icmp-ne-to-icmp-ugt.ll
@@ -0,0 +1,255 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt < %s -instcombine -S | FileCheck %s
+
+; https://bugs.llvm.org/show_bug.cgi?id=38123
+
+; Pattern:
+;   x & ((-1 << y) >> y) != x
+; Should be transformed into:
+;   x u> ((-1 << y) >> y)
+
+; This pattern is uncanonical, but we can not canonicalize it due to extra uses.
+
+declare void @use8(i8)
+declare void @use2i8(<2 x i8>)
+declare void @use3i8(<3 x i8>)
+
+; ============================================================================ ;
+; Basic positive tests
+; ============================================================================ ;
+
+define i1 @p0(i8 %x, i8 %y) {
+; CHECK-LABEL: @p0(
+; CHECK-NEXT:    [[T0:%.*]] = shl i8 -1, [[Y:%.*]]
+; CHECK-NEXT:    call void @use8(i8 [[T0]])
+; CHECK-NEXT:    [[T1:%.*]] = lshr i8 [[T0]], [[Y]]
+; CHECK-NEXT:    [[T2:%.*]] = and i8 [[T1]], [[X:%.*]]
+; CHECK-NEXT:    [[RET:%.*]] = icmp ne i8 [[T2]], [[X]]
+; CHECK-NEXT:    ret i1 [[RET]]
+;
+  %t0 = shl i8 -1, %y
+  call void @use8(i8 %t0)
+  %t1 = lshr i8 %t0, %y
+  %t2 = and i8 %t1, %x
+  %ret = icmp ne i8 %t2, %x
+  ret i1 %ret
+}
+
+; ============================================================================ ;
+; Vector tests
+; ============================================================================ ;
+
+define <2 x i1> @p1_vec(<2 x i8> %x, <2 x i8> %y) {
+; CHECK-LABEL: @p1_vec(
+; CHECK-NEXT:    [[T0:%.*]] = shl <2 x i8> <i8 -1, i8 -1>, [[Y:%.*]]
+; CHECK-NEXT:    call void @use2i8(<2 x i8> [[T0]])
+; CHECK-NEXT:    [[T1:%.*]] = lshr <2 x i8> [[T0]], [[Y]]
+; CHECK-NEXT:    [[T2:%.*]] = and <2 x i8> [[T1]], [[X:%.*]]
+; CHECK-NEXT:    [[RET:%.*]] = icmp ne <2 x i8> [[T2]], [[X]]
+; CHECK-NEXT:    ret <2 x i1> [[RET]]
+;
+  %t0 = shl <2 x i8> <i8 -1, i8 -1>, %y
+  call void @use2i8(<2 x i8> %t0)
+  %t1 = lshr <2 x i8> %t0, %y
+  %t2 = and <2 x i8> %t1, %x
+  %ret = icmp ne <2 x i8> %t2, %x
+  ret <2 x i1> %ret
+}
+
+define <3 x i1> @p2_vec_undef0(<3 x i8> %x, <3 x i8> %y) {
+; CHECK-LABEL: @p2_vec_undef0(
+; CHECK-NEXT:    [[T0:%.*]] = shl <3 x i8> <i8 -1, i8 undef, i8 -1>, [[Y:%.*]]
+; CHECK-NEXT:    call void @use3i8(<3 x i8> [[T0]])
+; CHECK-NEXT:    [[T1:%.*]] = lshr <3 x i8> [[T0]], [[Y]]
+; CHECK-NEXT:    [[T2:%.*]] = and <3 x i8> [[T1]], [[X:%.*]]
+; CHECK-NEXT:    [[RET:%.*]] = icmp ne <3 x i8> [[T2]], [[X]]
+; CHECK-NEXT:    ret <3 x i1> [[RET]]
+;
+  %t0 = shl <3 x i8> <i8 -1, i8 undef, i8 -1>, %y
+  call void @use3i8(<3 x i8> %t0)
+  %t1 = lshr <3 x i8> %t0, %y
+  %t2 = and <3 x i8> %t1, %x
+  %ret = icmp ne <3 x i8> %t2, %x
+  ret <3 x i1> %ret
+}
+
+; ============================================================================ ;
+; Commutativity tests.
+; ============================================================================ ;
+
+declare i8 @gen8()
+
+define i1 @c0(i8 %y) {
+; CHECK-LABEL: @c0(
+; CHECK-NEXT:    [[T0:%.*]] = shl i8 -1, [[Y:%.*]]
+; CHECK-NEXT:    call void @use8(i8 [[T0]])
+; CHECK-NEXT:    [[T1:%.*]] = lshr i8 [[T0]], [[Y]]
+; CHECK-NEXT:    [[X:%.*]] = call i8 @gen8()
+; CHECK-NEXT:    [[T2:%.*]] = and i8 [[X]], [[T1]]
+; CHECK-NEXT:    [[RET:%.*]] = icmp ne i8 [[T2]], [[X]]
+; CHECK-NEXT:    ret i1 [[RET]]
+;
+  %t0 = shl i8 -1, %y
+  call void @use8(i8 %t0)
+  %t1 = lshr i8 %t0, %y
+  %x = call i8 @gen8()
+  %t2 = and i8 %x, %t1 ; swapped order
+  %ret = icmp ne i8 %t2, %x
+  ret i1 %ret
+}
+
+define i1 @c1(i8 %y) {
+; CHECK-LABEL: @c1(
+; CHECK-NEXT:    [[T0:%.*]] = shl i8 -1, [[Y:%.*]]
+; CHECK-NEXT:    call void @use8(i8 [[T0]])
+; CHECK-NEXT:    [[T1:%.*]] = lshr i8 [[T0]], [[Y]]
+; CHECK-NEXT:    [[X:%.*]] = call i8 @gen8()
+; CHECK-NEXT:    [[T2:%.*]] = and i8 [[T1]], [[X]]
+; CHECK-NEXT:    [[RET:%.*]] = icmp ne i8 [[X]], [[T2]]
+; CHECK-NEXT:    ret i1 [[RET]]
+;
+  %t0 = shl i8 -1, %y
+  call void @use8(i8 %t0)
+  %t1 = lshr i8 %t0, %y
+  %x = call i8 @gen8()
+  %t2 = and i8 %t1, %x
+  %ret = icmp ne i8 %x, %t2 ; swapped order
+  ret i1 %ret
+}
+
+define i1 @c2(i8 %y) {
+; CHECK-LABEL: @c2(
+; CHECK-NEXT:    [[T0:%.*]] = shl i8 -1, [[Y:%.*]]
+; CHECK-NEXT:    call void @use8(i8 [[T0]])
+; CHECK-NEXT:    [[T1:%.*]] = lshr i8 [[T0]], [[Y]]
+; CHECK-NEXT:    [[X:%.*]] = call i8 @gen8()
+; CHECK-NEXT:    [[T2:%.*]] = and i8 [[X]], [[T1]]
+; CHECK-NEXT:    [[RET:%.*]] = icmp ne i8 [[X]], [[T2]]
+; CHECK-NEXT:    ret i1 [[RET]]
+;
+  %t0 = shl i8 -1, %y
+  call void @use8(i8 %t0)
+  %t1 = lshr i8 %t0, %y
+  %x = call i8 @gen8()
+  %t2 = and i8 %x, %t1 ; swapped order
+  %ret = icmp ne i8 %x, %t2 ; swapped order
+  ret i1 %ret
+}
+
+; ============================================================================ ;
+; One-use tests. We don't care about multi-uses here.
+; ============================================================================ ;
+
+define i1 @oneuse0(i8 %x, i8 %y) {
+; CHECK-LABEL: @oneuse0(
+; CHECK-NEXT:    [[T0:%.*]] = shl i8 -1, [[Y:%.*]]
+; CHECK-NEXT:    call void @use8(i8 [[T0]])
+; CHECK-NEXT:    [[T1:%.*]] = lshr i8 [[T0]], [[Y]]
+; CHECK-NEXT:    call void @use8(i8 [[T1]])
+; CHECK-NEXT:    [[T2:%.*]] = and i8 [[T1]], [[X:%.*]]
+; CHECK-NEXT:    [[RET:%.*]] = icmp ne i8 [[T2]], [[X]]
+; CHECK-NEXT:    ret i1 [[RET]]
+;
+  %t0 = shl i8 -1, %y
+  call void @use8(i8 %t0) ; needed anyway
+  %t1 = lshr i8 %t0, %y
+  call void @use8(i8 %t1)
+  %t2 = and i8 %t1, %x
+  %ret = icmp ne i8 %t2, %x
+  ret i1 %ret
+}
+
+define i1 @oneuse1(i8 %x, i8 %y) {
+; CHECK-LABEL: @oneuse1(
+; CHECK-NEXT:    [[T0:%.*]] = shl i8 -1, [[Y:%.*]]
+; CHECK-NEXT:    call void @use8(i8 [[T0]])
+; CHECK-NEXT:    [[T1:%.*]] = lshr i8 [[T0]], [[Y]]
+; CHECK-NEXT:    [[T2:%.*]] = and i8 [[T1]], [[X:%.*]]
+; CHECK-NEXT:    call void @use8(i8 [[T2]])
+; CHECK-NEXT:    [[RET:%.*]] = icmp ne i8 [[T2]], [[X]]
+; CHECK-NEXT:    ret i1 [[RET]]
+;
+  %t0 = shl i8 -1, %y
+  call void @use8(i8 %t0) ; needed anyway
+  %t1 = lshr i8 %t0, %y
+  %t2 = and i8 %t1, %x
+  call void @use8(i8 %t2)
+  %ret = icmp ne i8 %t2, %x
+  ret i1 %ret
+}
+
+define i1 @oneuse2(i8 %x, i8 %y) {
+; CHECK-LABEL: @oneuse2(
+; CHECK-NEXT:    [[T0:%.*]] = shl i8 -1, [[Y:%.*]]
+; CHECK-NEXT:    call void @use8(i8 [[T0]])
+; CHECK-NEXT:    [[T1:%.*]] = lshr i8 [[T0]], [[Y]]
+; CHECK-NEXT:    call void @use8(i8 [[T1]])
+; CHECK-NEXT:    [[T2:%.*]] = and i8 [[T1]], [[X:%.*]]
+; CHECK-NEXT:    call void @use8(i8 [[T2]])
+; CHECK-NEXT:    [[RET:%.*]] = icmp ne i8 [[T2]], [[X]]
+; CHECK-NEXT:    ret i1 [[RET]]
+;
+  %t0 = shl i8 -1, %y
+  call void @use8(i8 %t0)
+  %t1 = lshr i8 %t0, %y
+  call void @use8(i8 %t1)
+  %t2 = and i8 %t1, %x
+  call void @use8(i8 %t2)
+  %ret = icmp ne i8 %t2, %x
+  ret i1 %ret
+}
+
+; ============================================================================ ;
+; Negative tests
+; ============================================================================ ;
+
+define i1 @n0(i8 %x, i8 %y, i8 %notx) {
+; CHECK-LABEL: @n0(
+; CHECK-NEXT:    [[T0:%.*]] = shl i8 -1, [[Y:%.*]]
+; CHECK-NEXT:    call void @use8(i8 [[T0]])
+; CHECK-NEXT:    [[T1:%.*]] = lshr i8 [[T0]], [[Y]]
+; CHECK-NEXT:    [[T2:%.*]] = and i8 [[T1]], [[X:%.*]]
+; CHECK-NEXT:    [[RET:%.*]] = icmp ne i8 [[T2]], [[NOTX:%.*]]
+; CHECK-NEXT:    ret i1 [[RET]]
+;
+  %t0 = shl i8 -1, %y
+  call void @use8(i8 %t0)
+  %t1 = lshr i8 %t0, %y
+  %t2 = and i8 %t1, %x
+  %ret = icmp ne i8 %t2, %notx ; not %x
+  ret i1 %ret
+}
+
+define i1 @n1(i8 %x, i8 %y) {
+; CHECK-LABEL: @n1(
+; CHECK-NEXT:    [[T0:%.*]] = shl i8 1, [[Y:%.*]]
+; CHECK-NEXT:    call void @use8(i8 [[T0]])
+; CHECK-NEXT:    [[T1:%.*]] = lshr i8 [[T0]], [[Y]]
+; CHECK-NEXT:    [[T2:%.*]] = and i8 [[T1]], [[X:%.*]]
+; CHECK-NEXT:    [[RET:%.*]] = icmp ne i8 [[T2]], [[X]]
+; CHECK-NEXT:    ret i1 [[RET]]
+;
+  %t0 = shl i8 1, %y ; not -1
+  call void @use8(i8 %t0)
+  %t1 = lshr i8 %t0, %y
+  %t2 = and i8 %t1, %x
+  %ret = icmp ne i8 %t2, %x
+  ret i1 %ret
+}
+
+define i1 @n2(i8 %x, i8 %y1, i8 %y2) {
+; CHECK-LABEL: @n2(
+; CHECK-NEXT:    [[T0:%.*]] = shl i8 -1, [[Y1:%.*]]
+; CHECK-NEXT:    call void @use8(i8 [[T0]])
+; CHECK-NEXT:    [[T1:%.*]] = lshr i8 [[T0]], [[Y2:%.*]]
+; CHECK-NEXT:    [[T2:%.*]] = and i8 [[T1]], [[X:%.*]]
+; CHECK-NEXT:    [[RET:%.*]] = icmp ne i8 [[T2]], [[X]]
+; CHECK-NEXT:    ret i1 [[RET]]
+;
+  %t0 = shl i8 -1, %y1 ; not %y2
+  call void @use8(i8 %t0)
+  %t1 = lshr i8 %t0, %y2 ; not %y1
+  %t2 = and i8 %t1, %x
+  %ret = icmp ne i8 %t2, %x
+  ret i1 %ret
+}