[InstCombine] Test cases for D154206

[0xdc03]

Summary

Create a test case to test the fold for the expression pattern
'usub_sat(X, C) pred C2'.

[0xdc03]

• Rebase on main

[nikic]

llvm/test/Transforms/InstCombine/icmp-usub-sat.ll

54

ult 1 is eq 0 which is a special case. I'd adjust the constant to be 2 here.

179

Pick different constants so it's not always false?

258

The standard pattern for multi-use tests is call void @use(i8 %sub). Avoids any funny folds.

277

As you don't allow multi-use folds, it's enough to have a single test to cover this -- there's no much in point in having 10 tests that all show the same thing.

[0xdc03]

• Address reviewer comments
  • Fix cases which return true/false/zeroinitializer
  • Fix (and remove a lot of) multi-use tests
  • Reorganize some cases

[0xdc03]

Hopefully this fixes everything.

[nikic]

LGTM

llvm/test/Transforms/InstCombine/icmp-usub-sat.ll

+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 2
+; RUN: opt < %s -passes=instcombine -S | FileCheck %s
+
+; Tests for InstCombineCompares.cpp::foldICmpUSubSatWithConstant
+; https://github.com/llvm/llvm-project/issues/58342
+
+; ==============================================================================
+; Basic tests with one user and positive arguments
+; ==============================================================================
+define i1 @icmp_eq_basic_positive(i8 %arg) {
+; CHECK-LABEL: define i1 @icmp_eq_basic_positive
+; CHECK-SAME: (i8 [[ARG:%.*]]) {
+; CHECK-NEXT:    [[SUB:%.*]] = call i8 @llvm.usub.sat.i8(i8 [[ARG]], i8 2)
+; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i8 [[SUB]], 5
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %sub = call i8 @llvm.usub.sat.i8(i8 %arg, i8 2)
+  %cmp = icmp eq i8 %sub, 5
+  ret i1 %cmp
+}
+
+define i1 @icmp_ne_basic_positive(i16 %arg) {
+; CHECK-LABEL: define i1 @icmp_ne_basic_positive
+; CHECK-SAME: (i16 [[ARG:%.*]]) {
+; CHECK-NEXT:    [[SUB:%.*]] = call i16 @llvm.usub.sat.i16(i16 [[ARG]], i16 8)
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ne i16 [[SUB]], 9
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %sub = call i16 @llvm.usub.sat.i16(i16 %arg, i16 8)
+  %cmp = icmp ne i16 %sub, 9
+  ret i1 %cmp
+}
+
+define i1 @icmp_ule_basic_positive(i32 %arg) {
+; CHECK-LABEL: define i1 @icmp_ule_basic_positive
+; CHECK-SAME: (i32 [[ARG:%.*]]) {
+; CHECK-NEXT:    [[SUB:%.*]] = call i32 @llvm.usub.sat.i32(i32 [[ARG]], i32 6)
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i32 [[SUB]], 4
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %sub = call i32 @llvm.usub.sat.i32(i32 %arg, i32 6)
+  %cmp = icmp ule i32 %sub, 3
+  ret i1 %cmp
+}
+
+define i1 @icmp_ult_basic_positive(i64 %arg) {
+; CHECK-LABEL: define i1 @icmp_ult_basic_positive
+; CHECK-SAME: (i64 [[ARG:%.*]]) {
+; CHECK-NEXT:    [[SUB:%.*]] = call i64 @llvm.usub.sat.i64(i64 [[ARG]], i64 5)
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i64 [[SUB]], 2
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %sub = call i64 @llvm.usub.sat.i64(i64 %arg, i64 5)
+  %cmp = icmp ult i64 %sub, 2
+  ret i1 %cmp
+}
+
+define i1 @icmp_uge_basic_positive(i8 %arg) {
+; CHECK-LABEL: define i1 @icmp_uge_basic_positive
+; CHECK-SAME: (i8 [[ARG:%.*]]) {
+; CHECK-NEXT:    [[SUB:%.*]] = call i8 @llvm.usub.sat.i8(i8 [[ARG]], i8 4)
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ugt i8 [[SUB]], 3
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %sub = call i8 @llvm.usub.sat.i8(i8 %arg, i8 4)
+  %cmp = icmp uge i8 %sub, 4
+  ret i1 %cmp
+}
+
+define i1 @icmp_ugt_basic_positive(i16 %arg) {
+; CHECK-LABEL: define i1 @icmp_ugt_basic_positive
+; CHECK-SAME: (i16 [[ARG:%.*]]) {
+; CHECK-NEXT:    [[SUB:%.*]] = call i16 @llvm.usub.sat.i16(i16 [[ARG]], i16 1)
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ugt i16 [[SUB]], 3
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %sub = call i16 @llvm.usub.sat.i16(i16 %arg, i16 1)
+  %cmp = icmp ugt i16 %sub, 3
+  ret i1 %cmp
+}
+
+define i1 @icmp_sle_basic_positive(i32 %arg) {
+; CHECK-LABEL: define i1 @icmp_sle_basic_positive
+; CHECK-SAME: (i32 [[ARG:%.*]]) {
+; CHECK-NEXT:    [[SUB:%.*]] = call i32 @llvm.usub.sat.i32(i32 [[ARG]], i32 10)
+; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[SUB]], 9
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %sub = call i32 @llvm.usub.sat.i32(i32 %arg, i32 10)
+  %cmp = icmp sle i32 %sub, 8
+  ret i1 %cmp
+}
+
+define i1 @icmp_slt_basic_positive(i64 %arg) {
+; CHECK-LABEL: define i1 @icmp_slt_basic_positive
+; CHECK-SAME: (i64 [[ARG:%.*]]) {
+; CHECK-NEXT:    [[SUB:%.*]] = call i64 @llvm.usub.sat.i64(i64 [[ARG]], i64 24)
+; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i64 [[SUB]], 5
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %sub = call i64 @llvm.usub.sat.i64(i64 %arg, i64 24)
+  %cmp = icmp slt i64 %sub, 5
+  ret i1 %cmp
+}
+
+define i1 @icmp_sge_basic_positive(i8 %arg) {
+; CHECK-LABEL: define i1 @icmp_sge_basic_positive
+; CHECK-SAME: (i8 [[ARG:%.*]]) {
+; CHECK-NEXT:    [[SUB:%.*]] = call i8 @llvm.usub.sat.i8(i8 [[ARG]], i8 1)
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i8 [[SUB]], 3
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %sub = call i8 @llvm.usub.sat.i8(i8 %arg, i8 1)
+  %cmp = icmp sge i8 %sub, 4
+  ret i1 %cmp
+}
+
+define i1 @icmp_sgt_basic_positive(i16 %arg) {
+; CHECK-LABEL: define i1 @icmp_sgt_basic_positive
+; CHECK-SAME: (i16 [[ARG:%.*]]) {
+; CHECK-NEXT:    [[SUB:%.*]] = call i16 @llvm.usub.sat.i16(i16 [[ARG]], i16 2)
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i16 [[SUB]], 5
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %sub = call i16 @llvm.usub.sat.i16(i16 %arg, i16 2)
+  %cmp = icmp sgt i16 %sub, 5
+  ret i1 %cmp
+}
+
+; ==============================================================================
+; Basic tests with one user and negative arguments
+; ==============================================================================
+define i1 @icmp_eq_basic_negative(i8 %arg) {
+; CHECK-LABEL: define i1 @icmp_eq_basic_negative
+; CHECK-SAME: (i8 [[ARG:%.*]]) {
+; CHECK-NEXT:    [[SUB:%.*]] = call i8 @llvm.usub.sat.i8(i8 [[ARG]], i8 -20)
+; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i8 [[SUB]], 5
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %sub = call i8 @llvm.usub.sat.i8(i8 %arg, i8 -20)
+  %cmp = icmp eq i8 %sub, 5
+  ret i1 %cmp
+}
+
+define i1 @icmp_ne_basic_negative(i16 %arg) {
+; CHECK-LABEL: define i1 @icmp_ne_basic_negative
+; CHECK-SAME: (i16 [[ARG:%.*]]) {
+; CHECK-NEXT:    [[SUB:%.*]] = call i16 @llvm.usub.sat.i16(i16 [[ARG]], i16 -80)
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ne i16 [[SUB]], 9
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %sub = call i16 @llvm.usub.sat.i16(i16 %arg, i16 -80)
+  %cmp = icmp ne i16 %sub, 9
+  ret i1 %cmp
+}
+
+define i1 @icmp_ule_basic_negative(i32 %arg) {
+; CHECK-LABEL: define i1 @icmp_ule_basic_negative
+; CHECK-SAME: (i32 [[ARG:%.*]]) {
+; CHECK-NEXT:    [[SUB:%.*]] = call i32 @llvm.usub.sat.i32(i32 [[ARG]], i32 -6)
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i32 [[SUB]], 4
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %sub = call i32 @llvm.usub.sat.i32(i32 %arg, i32 -6)
+  %cmp = icmp ule i32 %sub, 3
+  ret i1 %cmp
+}
+
+define i1 @icmp_ult_basic_negative(i64 %arg) {
+; CHECK-LABEL: define i1 @icmp_ult_basic_negative
+; CHECK-SAME: (i64 [[ARG:%.*]]) {
+; CHECK-NEXT:    [[SUB:%.*]] = call i64 @llvm.usub.sat.i64(i64 [[ARG]], i64 -10)
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i64 [[SUB]], 2
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %sub = call i64 @llvm.usub.sat.i64(i64 %arg, i64 -10)
+  %cmp = icmp ult i64 %sub, 2
+  ret i1 %cmp
+}
+
+define i1 @icmp_uge_basic_negative(i8 %arg) {
+; CHECK-LABEL: define i1 @icmp_uge_basic_negative
+; CHECK-SAME: (i8 [[ARG:%.*]]) {
+; CHECK-NEXT:    [[SUB:%.*]] = call i8 @llvm.usub.sat.i8(i8 [[ARG]], i8 -4)
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ugt i8 [[SUB]], 1
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %sub = call i8 @llvm.usub.sat.i8(i8 %arg, i8 -4)
+  %cmp = icmp uge i8 %sub, 2
+  ret i1 %cmp
+}
+
+define i1 @icmp_ugt_basic_negative(i16 %arg) {
+; CHECK-LABEL: define i1 @icmp_ugt_basic_negative
+; CHECK-SAME: (i16 [[ARG:%.*]]) {
+; CHECK-NEXT:    [[SUB:%.*]] = call i16 @llvm.usub.sat.i16(i16 [[ARG]], i16 -10)
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ugt i16 [[SUB]], 3
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %sub = call i16 @llvm.usub.sat.i16(i16 %arg, i16 -10)
+  %cmp = icmp ugt i16 %sub, 3
+  ret i1 %cmp
+}
+
+define i1 @icmp_sle_basic_negative(i32 %arg) {
+; CHECK-LABEL: define i1 @icmp_sle_basic_negative
+; CHECK-SAME: (i32 [[ARG:%.*]]) {
+; CHECK-NEXT:    [[SUB:%.*]] = call i32 @llvm.usub.sat.i32(i32 [[ARG]], i32 -10)
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i32 [[SUB]], 9
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %sub = call i32 @llvm.usub.sat.i32(i32 %arg, i32 -10)
+  %cmp = icmp sle i32 %sub, 8
+  ret i1 %cmp
+}
+
+define i1 @icmp_slt_basic_negative(i64 %arg) {
+; CHECK-LABEL: define i1 @icmp_slt_basic_negative
+; CHECK-SAME: (i64 [[ARG:%.*]]) {
+; CHECK-NEXT:    [[SUB:%.*]] = call i64 @llvm.usub.sat.i64(i64 [[ARG]], i64 -24)
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i64 [[SUB]], 5
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %sub = call i64 @llvm.usub.sat.i64(i64 %arg, i64 -24)
+  %cmp = icmp slt i64 %sub, 5
+  ret i1 %cmp
+}
+
+define i1 @icmp_sge_basic_negative(i8 %arg) {
+; CHECK-LABEL: define i1 @icmp_sge_basic_negative
+; CHECK-SAME: (i8 [[ARG:%.*]]) {
+; CHECK-NEXT:    [[SUB:%.*]] = call i8 @llvm.usub.sat.i8(i8 [[ARG]], i8 -10)
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ugt i8 [[SUB]], 3
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %sub = call i8 @llvm.usub.sat.i8(i8 %arg, i8 -10)
+  %cmp = icmp sge i8 %sub, 4
+  ret i1 %cmp
+}
+
+define i1 @icmp_sgt_basic_negative(i16 %arg) {
+; CHECK-LABEL: define i1 @icmp_sgt_basic_negative
+; CHECK-SAME: (i16 [[ARG:%.*]]) {
+; CHECK-NEXT:    [[SUB:%.*]] = call i16 @llvm.usub.sat.i16(i16 [[ARG]], i16 -20)
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ugt i16 [[SUB]], 5
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %sub = call i16 @llvm.usub.sat.i16(i16 %arg, i16 -20)
+  %cmp = icmp sgt i16 %sub, 5
+  ret i1 %cmp
+}
+
+; ==============================================================================
+; Tests with more than user and positive arguments
+; ==============================================================================
+define i1 @icmp_eq_multiuse_positive(i8 %arg) {
+; CHECK-LABEL: define i1 @icmp_eq_multiuse_positive
+; CHECK-SAME: (i8 [[ARG:%.*]]) {
+; CHECK-NEXT:    [[SUB:%.*]] = call i8 @llvm.usub.sat.i8(i8 [[ARG]], i8 2)
+; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i8 [[SUB]], 5
+; CHECK-NEXT:    call void @use.i8(i8 [[SUB]])
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %sub = call i8 @llvm.usub.sat.i8(i8 %arg, i8 2)
+  %cmp = icmp eq i8 %sub, 5
+  call void @use.i8(i8 %sub)
+  ret i1 %cmp
+}
+
+; ==============================================================================
+; Tests with more than one user and negative arguments
+; ==============================================================================
+define i1 @icmp_eq_multiuse_negative(i8 %arg) {
+; CHECK-LABEL: define i1 @icmp_eq_multiuse_negative
+; CHECK-SAME: (i8 [[ARG:%.*]]) {
+; CHECK-NEXT:    [[SUB:%.*]] = call i8 @llvm.usub.sat.i8(i8 [[ARG]], i8 -2)
+; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i8 [[ARG]], -1
+; CHECK-NEXT:    call void @use.i8(i8 [[SUB]])
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %sub = call i8 @llvm.usub.sat.i8(i8 %arg, i8 -2)
+  %cmp = icmp eq i8 %sub, 1
+  call void @use.i8(i8 %sub)
+  ret i1 %cmp
+}
+
+; ==============================================================================
+; Tests with vector types and positive arguments
+; ==============================================================================
+define <2 x i1> @icmp_eq_vector_positive_equal(<2 x i8> %arg) {
+; CHECK-LABEL: define <2 x i1> @icmp_eq_vector_positive_equal
+; CHECK-SAME: (<2 x i8> [[ARG:%.*]]) {
+; CHECK-NEXT:    [[SUB:%.*]] = call <2 x i8> @llvm.usub.sat.v2i8(<2 x i8> [[ARG]], <2 x i8> <i8 2, i8 2>)
+; CHECK-NEXT:    [[CMP:%.*]] = icmp eq <2 x i8> [[SUB]], <i8 5, i8 5>
+; CHECK-NEXT:    ret <2 x i1> [[CMP]]
+;
+  %sub = call <2 x i8> @llvm.usub.sat.v2i8(<2 x i8> %arg, <2 x i8> <i8 2, i8 2>)
+  %cmp = icmp eq <2 x i8> %sub, <i8 5, i8 5>
+  ret <2 x i1> %cmp
+}
+
+define <2 x i1> @icmp_eq_vector_positive_unequal(<2 x i8> %arg) {
+; CHECK-LABEL: define <2 x i1> @icmp_eq_vector_positive_unequal
+; CHECK-SAME: (<2 x i8> [[ARG:%.*]]) {
+; CHECK-NEXT:    [[SUB:%.*]] = call <2 x i8> @llvm.usub.sat.v2i8(<2 x i8> [[ARG]], <2 x i8> <i8 1, i8 2>)
+; CHECK-NEXT:    [[CMP:%.*]] = icmp eq <2 x i8> [[SUB]], <i8 5, i8 6>
+; CHECK-NEXT:    ret <2 x i1> [[CMP]]
+;
+  %sub = call <2 x i8> @llvm.usub.sat.v2i8(<2 x i8> %arg, <2 x i8> <i8 1, i8 2>)
+  %cmp = icmp eq <2 x i8> %sub, <i8 5, i8 6>
+  ret <2 x i1> %cmp
+}
+
+define <2 x i1> @icmp_ne_vector_positive_equal(<2 x i16> %arg) {
+; CHECK-LABEL: define <2 x i1> @icmp_ne_vector_positive_equal
+; CHECK-SAME: (<2 x i16> [[ARG:%.*]]) {
+; CHECK-NEXT:    [[SUB:%.*]] = call <2 x i16> @llvm.usub.sat.v2i16(<2 x i16> [[ARG]], <2 x i16> <i16 32, i16 32>)
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ne <2 x i16> [[SUB]], <i16 5, i16 5>
+; CHECK-NEXT:    ret <2 x i1> [[CMP]]
+;
+  %sub = call <2 x i16> @llvm.usub.sat.v2i16(<2 x i16> %arg, <2 x i16> <i16 32, i16 32>)
+  %cmp = icmp ne <2 x i16> %sub, <i16 5, i16 5>
+  ret <2 x i1> %cmp
+}
+
+define <2 x i1> @icmp_ne_vector_positive_unequal(<2 x i16> %arg) {
+; CHECK-LABEL: define <2 x i1> @icmp_ne_vector_positive_unequal
+; CHECK-SAME: (<2 x i16> [[ARG:%.*]]) {
+; CHECK-NEXT:    [[SUB:%.*]] = call <2 x i16> @llvm.usub.sat.v2i16(<2 x i16> [[ARG]], <2 x i16> <i16 3, i16 33>)
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ne <2 x i16> [[SUB]], <i16 7, i16 6>
+; CHECK-NEXT:    ret <2 x i1> [[CMP]]
+;
+  %sub = call <2 x i16> @llvm.usub.sat.v2i16(<2 x i16> %arg, <2 x i16> <i16 3, i16 33>)
+  %cmp = icmp ne <2 x i16> %sub, <i16 7, i16 6>
+  ret <2 x i1> %cmp
+}
+
+define <2 x i1> @icmp_ule_vector_positive_equal(<2 x i32> %arg) {
+; CHECK-LABEL: define <2 x i1> @icmp_ule_vector_positive_equal
+; CHECK-SAME: (<2 x i32> [[ARG:%.*]]) {
+; CHECK-NEXT:    [[SUB:%.*]] = call <2 x i32> @llvm.usub.sat.v2i32(<2 x i32> [[ARG]], <2 x i32> <i32 32, i32 32>)
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ult <2 x i32> [[SUB]], <i32 5, i32 5>
+; CHECK-NEXT:    ret <2 x i1> [[CMP]]
+;
+  %sub = call <2 x i32> @llvm.usub.sat.v2i32(<2 x i32> %arg, <2 x i32> <i32 32, i32 32>)
+  %cmp = icmp ult <2 x i32> %sub, <i32 5, i32 5>
+  ret <2 x i1> %cmp
+}
+
+define <2 x i1> @icmp_ule_vector_positive_unequal(<2 x i32> %arg) {
+; CHECK-LABEL: define <2 x i1> @icmp_ule_vector_positive_unequal
+; CHECK-SAME: (<2 x i32> [[ARG:%.*]]) {
+; CHECK-NEXT:    [[SUB:%.*]] = call <2 x i32> @llvm.usub.sat.v2i32(<2 x i32> [[ARG]], <2 x i32> <i32 3, i32 35>)
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ult <2 x i32> [[SUB]], <i32 5, i32 7>
+; CHECK-NEXT:    ret <2 x i1> [[CMP]]
+;
+  %sub = call <2 x i32> @llvm.usub.sat.v2i32(<2 x i32> %arg, <2 x i32> <i32 3, i32 35>)
+  %cmp = icmp ult <2 x i32> %sub, <i32 5, i32 7>
+  ret <2 x i1> %cmp
+}
+
+define <2 x i1> @icmp_sgt_vector_positive_equal(<2 x i64> %arg) {
+; CHECK-LABEL: define <2 x i1> @icmp_sgt_vector_positive_equal
+; CHECK-SAME: (<2 x i64> [[ARG:%.*]]) {
+; CHECK-NEXT:    [[SUB:%.*]] = call <2 x i64> @llvm.usub.sat.v2i64(<2 x i64> [[ARG]], <2 x i64> <i64 409623, i64 409623>)
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt <2 x i64> [[SUB]], <i64 1234, i64 1234>
+; CHECK-NEXT:    ret <2 x i1> [[CMP]]
+;
+  %sub = call <2 x i64> @llvm.usub.sat.v2i64(<2 x i64> %arg, <2 x i64> <i64 409623, i64 409623>)
+  %cmp = icmp sgt <2 x i64> %sub, <i64 1234, i64 1234>
+  ret <2 x i1> %cmp
+}
+
+define <2 x i1> @icmp_sgt_vector_positive_unequal(<2 x i64> %arg) {
+; CHECK-LABEL: define <2 x i1> @icmp_sgt_vector_positive_unequal
+; CHECK-SAME: (<2 x i64> [[ARG:%.*]]) {
+; CHECK-NEXT:    [[SUB:%.*]] = call <2 x i64> @llvm.usub.sat.v2i64(<2 x i64> [[ARG]], <2 x i64> <i64 320498, i64 409623>)
+; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt <2 x i64> [[SUB]], <i64 1234, i64 3456>
+; CHECK-NEXT:    ret <2 x i1> [[CMP]]
+;
+  %sub = call <2 x i64> @llvm.usub.sat.v2i64(<2 x i64> %arg, <2 x i64> <i64 320498, i64 409623>)
+  %cmp = icmp sgt <2 x i64> %sub, <i64 1234, i64 3456>
+  ret <2 x i1> %cmp
+}
+
+; ==============================================================================
+; Tests with vector types and negative arguments
+; ==============================================================================
+define <2 x i1> @icmp_eq_vector_negative_equal(<2 x i8> %arg) {
+; CHECK-LABEL: define <2 x i1> @icmp_eq_vector_negative_equal
+; CHECK-SAME: (<2 x i8> [[ARG:%.*]]) {
+; CHECK-NEXT:    [[SUB:%.*]] = call <2 x i8> @llvm.usub.sat.v2i8(<2 x i8> [[ARG]], <2 x i8> <i8 -5, i8 -5>)
+; CHECK-NEXT:    [[CMP:%.*]] = icmp eq <2 x i8> [[SUB]], <i8 2, i8 2>
+; CHECK-NEXT:    ret <2 x i1> [[CMP]]
+;
+  %sub = call <2 x i8> @llvm.usub.sat.v2i8(<2 x i8> %arg, <2 x i8> <i8 -5, i8 -5>)
+  %cmp = icmp eq <2 x i8> %sub, <i8 2, i8 2>
+  ret <2 x i1> %cmp
+}
+
+define <2 x i1> @icmp_eq_vector_negative_unequal(<2 x i8> %arg) {
+; CHECK-LABEL: define <2 x i1> @icmp_eq_vector_negative_unequal
+; CHECK-SAME: (<2 x i8> [[ARG:%.*]]) {
+; CHECK-NEXT:    [[SUB:%.*]] = call <2 x i8> @llvm.usub.sat.v2i8(<2 x i8> [[ARG]], <2 x i8> <i8 -10, i8 -20>)
+; CHECK-NEXT:    [[CMP:%.*]] = icmp eq <2 x i8> [[SUB]], <i8 5, i8 6>
+; CHECK-NEXT:    ret <2 x i1> [[CMP]]
+;
+  %sub = call <2 x i8> @llvm.usub.sat.v2i8(<2 x i8> %arg, <2 x i8> <i8 -10, i8 -20>)
+  %cmp = icmp eq <2 x i8> %sub, <i8 5, i8 6>
+  ret <2 x i1> %cmp
+}
+
+; ==============================================================================
+; Tests with vector types, multiple uses and positive arguments
+; ==============================================================================
+define <2 x i1> @icmp_eq_vector_multiuse_positive_equal(<2 x i8> %arg) {
+; CHECK-LABEL: define <2 x i1> @icmp_eq_vector_multiuse_positive_equal
+; CHECK-SAME: (<2 x i8> [[ARG:%.*]]) {
+; CHECK-NEXT:    [[SUB:%.*]] = call <2 x i8> @llvm.usub.sat.v2i8(<2 x i8> [[ARG]], <2 x i8> <i8 2, i8 2>)
+; CHECK-NEXT:    [[CMP:%.*]] = icmp eq <2 x i8> [[SUB]], <i8 5, i8 5>
+; CHECK-NEXT:    call void @use.v2i8(<2 x i8> [[SUB]])
+; CHECK-NEXT:    ret <2 x i1> [[CMP]]
+;
+  %sub = call <2 x i8> @llvm.usub.sat.v2i8(<2 x i8> %arg, <2 x i8> <i8 2, i8 2>)
+  %cmp = icmp eq <2 x i8> %sub, <i8 5, i8 5>
+  call void @use.v2i8(<2 x i8> %sub)
+  ret <2 x i1> %cmp
+}
+
+; ==============================================================================
+; Tests with vector types, multiple uses and negative arguments
+; ==============================================================================
+define <2 x i1> @icmp_eq_vector_multiuse_negative_equal(<2 x i8> %arg) {
+; CHECK-LABEL: define <2 x i1> @icmp_eq_vector_multiuse_negative_equal
+; CHECK-SAME: (<2 x i8> [[ARG:%.*]]) {
+; CHECK-NEXT:    [[SUB:%.*]] = call <2 x i8> @llvm.usub.sat.v2i8(<2 x i8> [[ARG]], <2 x i8> <i8 -20, i8 -20>)
+; CHECK-NEXT:    [[CMP:%.*]] = icmp eq <2 x i8> [[SUB]], <i8 5, i8 5>
+; CHECK-NEXT:    call void @use.v2i8(<2 x i8> [[SUB]])
+; CHECK-NEXT:    ret <2 x i1> [[CMP]]
+;
+  %sub = call <2 x i8> @llvm.usub.sat.v2i8(<2 x i8> %arg, <2 x i8> <i8 -20, i8 -20>)
+  %cmp = icmp eq <2 x i8> %sub, <i8 5, i8 5>
+  call void @use.v2i8(<2 x i8> %sub)
+  ret <2 x i1> %cmp
+}
+
+declare i8 @llvm.usub.sat.i8(i8, i8)
+declare i16 @llvm.usub.sat.i16(i16, i16)
+declare i32 @llvm.usub.sat.i32(i32, i32)
+declare i64 @llvm.usub.sat.i64(i64, i64)
+
+declare <2 x i64> @llvm.usub.sat.v2i64(<2 x i64>, <2 x i64>)
+declare <2 x i32> @llvm.usub.sat.v2i32(<2 x i32>, <2 x i32>)
+declare <2 x i16> @llvm.usub.sat.v2i16(<2 x i16>, <2 x i16>)
+declare <2 x i8> @llvm.usub.sat.v2i8(<2 x i8>, <2 x i8>)
+
+declare void @use.i8(i8)
+declare void @use.v2i8(<2 x i8>)