From 2d1fea29231f1998e7123b3a1ce177284ae41cec Mon Sep 17 00:00:00 2001
From: Simon Pilgrim <llvm-dev@redking.me.uk>
Date: Fri, 16 Oct 2020 15:56:05 +0100
Subject: [PATCH] [InstCombine] Add vectors-with-undef tests for
 and(logicalshift(1,X),1) --> zext(X == 0)

---
 llvm/test/Transforms/InstCombine/and2.ll | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/llvm/test/Transforms/InstCombine/and2.ll b/llvm/test/Transforms/InstCombine/and2.ll
index 74b1204..6cf71ee 100644
--- a/llvm/test/Transforms/InstCombine/and2.ll
+++ b/llvm/test/Transforms/InstCombine/and2.ll
@@ -135,6 +135,17 @@ define <2 x i8> @and1_shl1_is_cmp_eq_0_vec(<2 x i8> %x) {
   ret <2 x i8> %and
 }
 
+define <2 x i8> @and1_shl1_is_cmp_eq_0_vec_undef(<2 x i8> %x) {
+; CHECK-LABEL: @and1_shl1_is_cmp_eq_0_vec_undef(
+; CHECK-NEXT:    [[SH:%.*]] = shl <2 x i8> <i8 1, i8 undef>, [[X:%.*]]
+; CHECK-NEXT:    [[AND:%.*]] = and <2 x i8> [[SH]], <i8 1, i8 undef>
+; CHECK-NEXT:    ret <2 x i8> [[AND]]
+;
+  %sh = shl <2 x i8> <i8 1, i8 undef>, %x
+  %and = and <2 x i8> %sh, <i8 1, i8 undef>
+  ret <2 x i8> %and
+}
+
 ; (1 >> x) & 1 --> zext(x == 0)
 
 define i8 @and1_lshr1_is_cmp_eq_0(i8 %x) {
@@ -176,6 +187,17 @@ define <2 x i8> @and1_lshr1_is_cmp_eq_0_vec(<2 x i8> %x) {
   ret <2 x i8> %and
 }
 
+define <2 x i8> @and1_lshr1_is_cmp_eq_0_vec_undef(<2 x i8> %x) {
+; CHECK-LABEL: @and1_lshr1_is_cmp_eq_0_vec_undef(
+; CHECK-NEXT:    [[SH:%.*]] = lshr <2 x i8> <i8 1, i8 undef>, [[X:%.*]]
+; CHECK-NEXT:    [[AND:%.*]] = and <2 x i8> [[SH]], <i8 1, i8 undef>
+; CHECK-NEXT:    ret <2 x i8> [[AND]]
+;
+  %sh = lshr <2 x i8> <i8 1, i8 undef>, %x
+  %and = and <2 x i8> %sh, <i8 1, i8 undef>
+  ret <2 x i8> %and
+}
+
 ; The add in this test is unnecessary because the LSBs of the LHS are 0 and the 'and' only consumes bits from those LSBs. It doesn't matter what happens to the upper bits.
 define i32 @test11(i32 %a, i32 %b) {
 ; CHECK-LABEL: @test11(
-- 
2.7.4