From ea6171c108c47c1ee486388adfa106e13e280e33 Mon Sep 17 00:00:00 2001
From: Sanjay Patel <spatel@rotateright.com>
Date: Wed, 25 May 2022 14:22:56 -0400
Subject: [PATCH] [InstCombine] add tests for icmp with udiv operand; NFC

This covers a generalization of one of the transforms
suggested in #55695.
---
 .../Transforms/InstCombine/icmp-div-constant.ll    | 78 ++++++++++++++++++++++
 1 file changed, 78 insertions(+)

diff --git a/llvm/test/Transforms/InstCombine/icmp-div-constant.ll b/llvm/test/Transforms/InstCombine/icmp-div-constant.ll
index aab916c..ff587dc 100644
--- a/llvm/test/Transforms/InstCombine/icmp-div-constant.ll
+++ b/llvm/test/Transforms/InstCombine/icmp-div-constant.ll
@@ -196,3 +196,81 @@ exit:
   ret i32 %add
 }
 
+define i1 @udiv_eq_umax(i8 %x, i8 %y) {
+; CHECK-LABEL: @udiv_eq_umax(
+; CHECK-NEXT:    [[D:%.*]] = udiv i8 [[X:%.*]], [[Y:%.*]]
+; CHECK-NEXT:    [[R:%.*]] = icmp eq i8 [[D]], -1
+; CHECK-NEXT:    ret i1 [[R]]
+;
+  %d = udiv i8 %x, %y
+  %r = icmp eq i8 %d, 255
+  ret i1 %r
+}
+
+define <2 x i1> @udiv_ne_umax(<2 x i5> %x, <2 x i5> %y) {
+; CHECK-LABEL: @udiv_ne_umax(
+; CHECK-NEXT:    [[D:%.*]] = udiv <2 x i5> [[X:%.*]], [[Y:%.*]]
+; CHECK-NEXT:    [[R:%.*]] = icmp ne <2 x i5> [[D]], <i5 -1, i5 -1>
+; CHECK-NEXT:    ret <2 x i1> [[R]]
+;
+  %d = udiv <2 x i5> %x, %y
+  %r = icmp ne <2 x i5> %d, <i5 -1, i5 -1>
+  ret <2 x i1> %r
+}
+
+define i1 @udiv_eq_big(i8 %x, i8 %y) {
+; CHECK-LABEL: @udiv_eq_big(
+; CHECK-NEXT:    [[D:%.*]] = udiv i8 [[X:%.*]], [[Y:%.*]]
+; CHECK-NEXT:    [[R:%.*]] = icmp eq i8 [[D]], -128
+; CHECK-NEXT:    ret i1 [[R]]
+;
+  %d = udiv i8 %x, %y
+  %r = icmp eq i8 %d, 128
+  ret i1 %r
+}
+
+define i1 @udiv_ne_big(i8 %x, i8 %y) {
+; CHECK-LABEL: @udiv_ne_big(
+; CHECK-NEXT:    [[D:%.*]] = udiv i8 [[X:%.*]], [[Y:%.*]]
+; CHECK-NEXT:    [[R:%.*]] = icmp ne i8 [[D]], -128
+; CHECK-NEXT:    ret i1 [[R]]
+;
+  %d = udiv i8 %x, %y
+  %r = icmp ne i8 %d, 128
+  ret i1 %r
+}
+
+define i1 @udiv_eq_not_big(i8 %x, i8 %y) {
+; CHECK-LABEL: @udiv_eq_not_big(
+; CHECK-NEXT:    [[D:%.*]] = udiv i8 [[X:%.*]], [[Y:%.*]]
+; CHECK-NEXT:    [[R:%.*]] = icmp eq i8 [[D]], 127
+; CHECK-NEXT:    ret i1 [[R]]
+;
+  %d = udiv i8 %x, %y
+  %r = icmp eq i8 %d, 127
+  ret i1 %r
+}
+
+define i1 @udiv_slt_umax(i8 %x, i8 %y) {
+; CHECK-LABEL: @udiv_slt_umax(
+; CHECK-NEXT:    [[D:%.*]] = udiv i8 [[X:%.*]], [[Y:%.*]]
+; CHECK-NEXT:    [[R:%.*]] = icmp slt i8 [[D]], -1
+; CHECK-NEXT:    ret i1 [[R]]
+;
+  %d = udiv i8 %x, %y
+  %r = icmp slt i8 %d, 255
+  ret i1 %r
+}
+
+define i1 @udiv_eq_umax_use(i32 %x, i32 %y) {
+; CHECK-LABEL: @udiv_eq_umax_use(
+; CHECK-NEXT:    [[D:%.*]] = udiv i32 [[X:%.*]], [[Y:%.*]]
+; CHECK-NEXT:    call void @use(i32 [[D]])
+; CHECK-NEXT:    [[R:%.*]] = icmp eq i32 [[D]], -1
+; CHECK-NEXT:    ret i1 [[R]]
+;
+  %d = udiv i32 %x, %y
+  call void @use(i32 %d)
+  %r = icmp eq i32 %d, -1
+  ret i1 %r
+}
-- 
2.7.4