From 9a452740ec89f856492841af3f9c616f5be96c7c Mon Sep 17 00:00:00 2001
From: Simon Pilgrim <llvm-dev@redking.me.uk>
Date: Mon, 12 Aug 2019 14:01:16 +0000
Subject: [PATCH] [X86][SSE] Add test showing missing demanded elts PSADBW
 handling

llvm-svn: 368575
---
 llvm/test/CodeGen/X86/psadbw.ll | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/llvm/test/CodeGen/X86/psadbw.ll b/llvm/test/CodeGen/X86/psadbw.ll
index 4691689..753e88c 100644
--- a/llvm/test/CodeGen/X86/psadbw.ll
+++ b/llvm/test/CodeGen/X86/psadbw.ll
@@ -13,5 +13,31 @@ define <2 x i64> @combine_psadbw_shift(<16 x i8> %0, <16 x i8> %1) {
   ret <2 x i64> %4
 }
 
+; Propagate the demanded result elements to the 8 aliasing source elements.
+define i64 @combine_psadbw_demandedelt(<16 x i8> %0, <16 x i8> %1) {
+; X86-LABEL: combine_psadbw_demandedelt:
+; X86:       # %bb.0:
+; X86-NEXT:    pshufd {{.*#+}} xmm0 = xmm0[0,1,3,2]
+; X86-NEXT:    pshufd {{.*#+}} xmm1 = xmm1[0,1,3,2]
+; X86-NEXT:    psadbw %xmm0, %xmm1
+; X86-NEXT:    movd %xmm1, %eax
+; X86-NEXT:    pshufd {{.*#+}} xmm0 = xmm1[1,1,2,3]
+; X86-NEXT:    movd %xmm0, %edx
+; X86-NEXT:    retl
+;
+; X64-LABEL: combine_psadbw_demandedelt:
+; X64:       # %bb.0:
+; X64-NEXT:    pshufd {{.*#+}} xmm0 = xmm0[0,1,3,2]
+; X64-NEXT:    pshufd {{.*#+}} xmm1 = xmm1[0,1,3,2]
+; X64-NEXT:    psadbw %xmm0, %xmm1
+; X64-NEXT:    movq %xmm1, %rax
+; X64-NEXT:    retq
+  %3 = shufflevector <16 x i8> %0, <16 x i8> %0, <16 x i32> <i32 0, i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7, i32 12, i32 13, i32 14, i32 15, i32 8, i32 9, i32 10, i32 11>
+  %4 = shufflevector <16 x i8> %1, <16 x i8> %1, <16 x i32> <i32 0, i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7, i32 12, i32 13, i32 14, i32 15, i32 8, i32 9, i32 10, i32 11>
+  %5 = tail call <2 x i64> @llvm.x86.sse2.psad.bw(<16 x i8> %3, <16 x i8> %4)
+  %6 = extractelement <2 x i64> %5, i32 0
+  ret i64 %6
+}
+
 declare <2 x i64> @llvm.x86.sse2.psad.bw(<16 x i8>, <16 x i8>)
 
-- 
2.7.4