From 90ac572331e5fd6e3d7a6b011b08dd692408e2b9 Mon Sep 17 00:00:00 2001
From: Chandler Carruth <chandlerc@gmail.com>
Date: Thu, 3 Jul 2014 07:04:38 +0000
Subject: [PATCH] [x86] Fix the completely broken vector widening legalization
 of bswap.

This operation was classified as a binary operation in the widening
logic for some reason (clearly, untested). It is in fact a unary
operation. Add a RUN line to a test to exercise this for x86.

Note that again the vector widening strategy doesn't regress anything
and in one case removes a totally unecessary instruction that we
couldn't avoid when promoting the element type.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212257 91177308-0d34-0410-b5e6-96231b3b80d8
---
 .../SelectionDAG/LegalizeVectorTypes.cpp      |  2 +-
 test/CodeGen/X86/bswap-vector.ll              | 29 +++++++++++++++++++
 2 files changed, 30 insertions(+), 1 deletion(-)

diff --git a/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp b/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp
index f8b1f3e702c..74f8f72c7ab 100644
--- a/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp
+++ b/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp
@@ -1549,7 +1549,6 @@ void DAGTypeLegalizer::WidenVectorResult(SDNode *N, unsigned ResNo) {
 
   case ISD::ADD:
   case ISD::AND:
-  case ISD::BSWAP:
   case ISD::MUL:
   case ISD::MULHS:
   case ISD::MULHU:
@@ -1596,6 +1595,7 @@ void DAGTypeLegalizer::WidenVectorResult(SDNode *N, unsigned ResNo) {
     Res = WidenVecRes_Convert(N);
     break;
 
+  case ISD::BSWAP:
   case ISD::CTLZ:
   case ISD::CTPOP:
   case ISD::CTTZ:
diff --git a/test/CodeGen/X86/bswap-vector.ll b/test/CodeGen/X86/bswap-vector.ll
index 3c931db2e27..9dc960d7779 100644
--- a/test/CodeGen/X86/bswap-vector.ll
+++ b/test/CodeGen/X86/bswap-vector.ll
@@ -1,6 +1,7 @@
 ; RUN: llc < %s -mcpu=x86-64 | FileCheck %s -check-prefix=CHECK-NOSSSE3
 ; RUN: llc < %s -mcpu=core2 | FileCheck %s -check-prefix=CHECK-SSSE3
 ; RUN: llc < %s -mcpu=core-avx2 | FileCheck %s -check-prefix=CHECK-AVX2
+; RUN: llc < %s -mcpu=core-avx2 -x86-experimental-vector-widening-legalization | FileCheck %s -check-prefix=CHECK-WIDE-AVX2
 target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"
 target triple = "x86_64-unknown-linux-gnu"
 
@@ -31,6 +32,10 @@ entry:
 ; CHECK-AVX2-LABEL: @test1
 ; CHECK-AVX2: vpshufb
 ; CHECK-AVX2-NEXT: retq
+
+; CHECK-WIDE-AVX2-LABEL: @test1
+; CHECK-WIDE-AVX2: vpshufb
+; CHECK-WIDE-AVX2-NEXT: retq
 }
 
 define <4 x i32> @test2(<4 x i32> %v) #0 {
@@ -52,6 +57,10 @@ entry:
 ; CHECK-AVX2-LABEL: @test2
 ; CHECK-AVX2: vpshufb
 ; CHECK-AVX2-NEXT: retq
+
+; CHECK-WIDE-AVX2-LABEL: @test2
+; CHECK-WIDE-AVX2: vpshufb
+; CHECK-WIDE-AVX2-NEXT: retq
 }
 
 define <2 x i64> @test3(<2 x i64> %v) #0 {
@@ -71,6 +80,10 @@ entry:
 ; CHECK-AVX2-LABEL: @test3
 ; CHECK-AVX2: vpshufb
 ; CHECK-AVX2-NEXT: retq
+
+; CHECK-WIDE-AVX2-LABEL: @test3
+; CHECK-WIDE-AVX2: vpshufb
+; CHECK-WIDE-AVX2-NEXT: retq
 }
 
 declare <16 x i16> @llvm.bswap.v16i16(<16 x i16>)
@@ -90,6 +103,10 @@ entry:
 ; CHECK-AVX2-LABEL: @test4
 ; CHECK-AVX2: vpshufb
 ; CHECK-AVX2-NEXT: retq
+
+; CHECK-WIDE-AVX2-LABEL: @test4
+; CHECK-WIDE-AVX2: vpshufb
+; CHECK-WIDE-AVX2-NEXT: retq
 }
 
 define <8 x i32> @test5(<8 x i32> %v) #0 {
@@ -105,6 +122,10 @@ entry:
 ; CHECK-AVX2-LABEL: @test5
 ; CHECK-AVX2: vpshufb
 ; CHECK-AVX2-NEXT: retq
+
+; CHECK-WIDE-AVX2-LABEL: @test5
+; CHECK-WIDE-AVX2: vpshufb
+; CHECK-WIDE-AVX2-NEXT: retq
 }
 
 define <4 x i64> @test6(<4 x i64> %v) #0 {
@@ -120,6 +141,10 @@ entry:
 ; CHECK-AVX2-LABEL: @test6
 ; CHECK-AVX2: vpshufb
 ; CHECK-AVX2-NEXT: retq
+
+; CHECK-WIDE-AVX2-LABEL: @test6
+; CHECK-WIDE-AVX2: vpshufb
+; CHECK-WIDE-AVX2-NEXT: retq
 }
 
 declare <4 x i16> @llvm.bswap.v4i16(<4 x i16>)
@@ -138,6 +163,10 @@ entry:
 ; CHECK-AVX2: vpshufb
 ; CHECK-AVX2: vpsrld $16
 ; CHECK-AVX2-NEXT: retq
+
+; CHECK-WIDE-AVX2-LABEL: @test7
+; CHECK-WIDE-AVX2: vpshufb
+; CHECK-WIDE-AVX2-NEXT: retq
 }
 
 attributes #0 = { nounwind uwtable }
-- 
2.34.1