From 7017a68c8bd669aecdf907fe442bf7a5422fc7e8 Mon Sep 17 00:00:00 2001
From: Sanjay Patel <spatel@rotateright.com>
Date: Sat, 13 Jul 2019 12:54:48 +0000
Subject: [PATCH] [InstCombine] add tests for umin/umax via usub.sat; NFC

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@365999 91177308-0d34-0410-b5e6-96231b3b80d8
---
 .../InstCombine/saturating-add-sub.ll         | 72 +++++++++++++++++++
 1 file changed, 72 insertions(+)

diff --git a/test/Transforms/InstCombine/saturating-add-sub.ll b/test/Transforms/InstCombine/saturating-add-sub.ll
index 364c80d205f..56e10626104 100644
--- a/test/Transforms/InstCombine/saturating-add-sub.ll
+++ b/test/Transforms/InstCombine/saturating-add-sub.ll
@@ -1614,3 +1614,75 @@ define i32 @unsigned_sat_constant_using_min_wrong_constant(i32 %x) {
   %r = add i32 %s, -42
   ret i32 %r
 }
+
+define i8 @umax(i8 %a, i8 %b) {
+; CHECK-LABEL: @umax(
+; CHECK-NEXT:    [[USUB:%.*]] = tail call i8 @llvm.usub.sat.i8(i8 [[A:%.*]], i8 [[B:%.*]])
+; CHECK-NEXT:    [[R:%.*]] = add i8 [[USUB]], [[B]]
+; CHECK-NEXT:    ret i8 [[R]]
+;
+  %usub = tail call i8 @llvm.usub.sat.i8(i8 %a, i8 %b)
+  %r = add i8 %usub, %b
+  ret i8 %r
+}
+
+define <2 x i8> @umax_vec(<2 x i8> %a, <2 x i8> %b) {
+; CHECK-LABEL: @umax_vec(
+; CHECK-NEXT:    [[USUB:%.*]] = tail call <2 x i8> @llvm.usub.sat.v2i8(<2 x i8> [[A:%.*]], <2 x i8> [[B:%.*]])
+; CHECK-NEXT:    [[R:%.*]] = add <2 x i8> [[USUB]], [[B]]
+; CHECK-NEXT:    ret <2 x i8> [[R]]
+;
+  %usub = tail call <2 x i8> @llvm.usub.sat.v2i8(<2 x i8> %a, <2 x i8> %b)
+  %r = add <2 x i8> %usub, %b
+  ret <2 x i8> %r
+}
+
+define i8 @umax_extra_use(i8 %a, i8 %b) {
+; CHECK-LABEL: @umax_extra_use(
+; CHECK-NEXT:    [[USUB:%.*]] = tail call i8 @llvm.usub.sat.i8(i8 [[A:%.*]], i8 [[B:%.*]])
+; CHECK-NEXT:    call void @use(i8 [[USUB]])
+; CHECK-NEXT:    [[R:%.*]] = add i8 [[USUB]], [[B]]
+; CHECK-NEXT:    ret i8 [[R]]
+;
+  %usub = tail call i8 @llvm.usub.sat.i8(i8 %a, i8 %b)
+  call void @use(i8 %usub)
+  %r = add i8 %usub, %b
+  ret i8 %r
+}
+
+define i8 @umin(i8 %a, i8 %b) {
+; CHECK-LABEL: @umin(
+; CHECK-NEXT:    [[USUB:%.*]] = tail call i8 @llvm.usub.sat.i8(i8 [[A:%.*]], i8 [[B:%.*]])
+; CHECK-NEXT:    [[R:%.*]] = sub i8 [[A]], [[USUB]]
+; CHECK-NEXT:    ret i8 [[R]]
+;
+  %usub = tail call i8 @llvm.usub.sat.i8(i8 %a, i8 %b)
+  %r = sub i8 %a, %usub
+  ret i8 %r
+}
+
+define <2 x i8> @umin_vec(<2 x i8> %a, <2 x i8> %b) {
+; CHECK-LABEL: @umin_vec(
+; CHECK-NEXT:    [[USUB:%.*]] = tail call <2 x i8> @llvm.usub.sat.v2i8(<2 x i8> [[A:%.*]], <2 x i8> [[B:%.*]])
+; CHECK-NEXT:    [[R:%.*]] = sub <2 x i8> [[A]], [[USUB]]
+; CHECK-NEXT:    ret <2 x i8> [[R]]
+;
+  %usub = tail call <2 x i8> @llvm.usub.sat.v2i8(<2 x i8> %a, <2 x i8> %b)
+  %r = sub <2 x i8> %a, %usub
+  ret <2 x i8> %r
+}
+
+define i8 @umin_extra_use(i8 %a, i8 %b) {
+; CHECK-LABEL: @umin_extra_use(
+; CHECK-NEXT:    [[USUB:%.*]] = tail call i8 @llvm.usub.sat.i8(i8 [[A:%.*]], i8 [[B:%.*]])
+; CHECK-NEXT:    call void @use(i8 [[USUB]])
+; CHECK-NEXT:    [[R:%.*]] = sub i8 [[A]], [[USUB]]
+; CHECK-NEXT:    ret i8 [[R]]
+;
+  %usub = tail call i8 @llvm.usub.sat.i8(i8 %a, i8 %b)
+  call void @use(i8 %usub)
+  %r = sub i8 %a, %usub
+  ret i8 %r
+}
+
+declare void @use(i8)
-- 
2.40.0