From 1fcc05880eb106562929885857f55f558dc2a36e Mon Sep 17 00:00:00 2001
From: Simon Pilgrim <llvm-dev@redking.me.uk>
Date: Tue, 12 Feb 2019 17:22:35 +0000
Subject: [PATCH] [X86][AVX] Enable shuffle combining support for zero_extend

A more limited version of rL352997 that had to be disabled in rL353198 - allow extension of any 128/256/512 bit vector that at least uses byte sized scalars.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@353860 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Target/X86/X86ISelLowering.cpp        | 12 +++++++---
 test/CodeGen/X86/vector-shuffle-256-v8.ll | 27 ++++++++++++++++-------
 2 files changed, 28 insertions(+), 11 deletions(-)

diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index 73dd495f6a8..f461dd3dd87 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -6793,17 +6793,23 @@ static bool getFauxShuffleMask(SDValue N, SmallVectorImpl<int> &Mask,
     Mask.append(NumElts, 0);
     return true;
   }
+  case ISD::ZERO_EXTEND:
   case ISD::ZERO_EXTEND_VECTOR_INREG: {
-    // TODO: Handle ISD::ZERO_EXTEND
     SDValue Src = N.getOperand(0);
-    MVT SrcVT = Src.getSimpleValueType();
+    EVT SrcVT = Src.getValueType();
+
+    // Zero-extended source must be a simple vector.
+    if (!SrcVT.isSimple() || (SrcVT.getSizeInBits() % 128) != 0 ||
+        (SrcVT.getScalarSizeInBits() % 8) != 0)
+      return false;
+
     unsigned NumSrcBitsPerElt = SrcVT.getScalarSizeInBits();
     DecodeZeroExtendMask(NumSrcBitsPerElt, NumBitsPerElt, NumElts, Mask);
 
     if (NumSizeInBits != SrcVT.getSizeInBits()) {
       assert((NumSizeInBits % SrcVT.getSizeInBits()) == 0 &&
              "Illegal zero-extension type");
-      SrcVT = MVT::getVectorVT(SrcVT.getScalarType(),
+      SrcVT = MVT::getVectorVT(SrcVT.getSimpleVT().getScalarType(),
                                NumSizeInBits / NumSrcBitsPerElt);
       Src = DAG.getNode(ISD::INSERT_SUBVECTOR, SDLoc(N), SrcVT,
                         DAG.getUNDEF(SrcVT), Src,
diff --git a/test/CodeGen/X86/vector-shuffle-256-v8.ll b/test/CodeGen/X86/vector-shuffle-256-v8.ll
index 651cb73d707..8d136704ca2 100644
--- a/test/CodeGen/X86/vector-shuffle-256-v8.ll
+++ b/test/CodeGen/X86/vector-shuffle-256-v8.ll
@@ -1526,9 +1526,8 @@ define <8 x i32> @shuffle_v8i32_08192a3b(<8 x i32> %a, <8 x i32> %b) {
 ;
 ; AVX512VL-LABEL: shuffle_v8i32_08192a3b:
 ; AVX512VL:       # %bb.0:
-; AVX512VL-NEXT:    vpmovzxdq {{.*#+}} ymm2 = xmm0[0],zero,xmm0[1],zero,xmm0[2],zero,xmm0[3],zero
-; AVX512VL-NEXT:    vmovdqa {{.*#+}} ymm0 = [0,8,2,9,4,10,6,11]
-; AVX512VL-NEXT:    vpermi2d %ymm1, %ymm2, %ymm0
+; AVX512VL-NEXT:    vmovdqa {{.*#+}} ymm2 = [0,8,1,9,2,10,3,11]
+; AVX512VL-NEXT:    vpermt2d %ymm1, %ymm2, %ymm0
 ; AVX512VL-NEXT:    retq
   %shuffle = shufflevector <8 x i32> %a, <8 x i32> %b, <8 x i32> <i32 0, i32 8, i32 1, i32 9, i32 2, i32 10, i32 3, i32 11>
   ret <8 x i32> %shuffle
@@ -1572,11 +1571,23 @@ define <8 x i32> @shuffle_v8i32_091b2d3f(<8 x i32> %a, <8 x i32> %b) {
 ; AVX1-NEXT:    vblendps {{.*#+}} ymm0 = ymm0[0],ymm1[1],ymm0[2],ymm1[3],ymm0[4],ymm1[5],ymm0[6],ymm1[7]
 ; AVX1-NEXT:    retq
 ;
-; AVX2OR512VL-LABEL: shuffle_v8i32_091b2d3f:
-; AVX2OR512VL:       # %bb.0:
-; AVX2OR512VL-NEXT:    vpmovzxdq {{.*#+}} ymm0 = xmm0[0],zero,xmm0[1],zero,xmm0[2],zero,xmm0[3],zero
-; AVX2OR512VL-NEXT:    vpblendd {{.*#+}} ymm0 = ymm0[0],ymm1[1],ymm0[2],ymm1[3],ymm0[4],ymm1[5],ymm0[6],ymm1[7]
-; AVX2OR512VL-NEXT:    retq
+; AVX2-LABEL: shuffle_v8i32_091b2d3f:
+; AVX2:       # %bb.0:
+; AVX2-NEXT:    vpmovzxdq {{.*#+}} ymm0 = xmm0[0],zero,xmm0[1],zero,xmm0[2],zero,xmm0[3],zero
+; AVX2-NEXT:    vpblendd {{.*#+}} ymm0 = ymm0[0],ymm1[1],ymm0[2],ymm1[3],ymm0[4],ymm1[5],ymm0[6],ymm1[7]
+; AVX2-NEXT:    retq
+;
+; AVX512VL-SLOW-LABEL: shuffle_v8i32_091b2d3f:
+; AVX512VL-SLOW:       # %bb.0:
+; AVX512VL-SLOW-NEXT:    vpmovzxdq {{.*#+}} ymm0 = xmm0[0],zero,xmm0[1],zero,xmm0[2],zero,xmm0[3],zero
+; AVX512VL-SLOW-NEXT:    vpblendd {{.*#+}} ymm0 = ymm0[0],ymm1[1],ymm0[2],ymm1[3],ymm0[4],ymm1[5],ymm0[6],ymm1[7]
+; AVX512VL-SLOW-NEXT:    retq
+;
+; AVX512VL-FAST-LABEL: shuffle_v8i32_091b2d3f:
+; AVX512VL-FAST:       # %bb.0:
+; AVX512VL-FAST-NEXT:    vmovdqa {{.*#+}} ymm2 = [0,9,1,11,2,13,3,15]
+; AVX512VL-FAST-NEXT:    vpermt2d %ymm1, %ymm2, %ymm0
+; AVX512VL-FAST-NEXT:    retq
   %shuffle = shufflevector <8 x i32> %a, <8 x i32> %b, <8 x i32> <i32 0, i32 9, i32 1, i32 11, i32 2, i32 13, i32 3, i32 15>
   ret <8 x i32> %shuffle
 }
-- 
2.40.0