[X86][AVX2] Add support for combining target shuffles to VPMOVZX

Initial 256-bit vector support - 512-bit support requires extra checks for AVX512BW support (PMOVZXBW) that will be handled in a future patch.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@294896 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index 0de7d1c173c29ed77ba9dab9f78ae8aa018f4b34..2a0ea9cfeaebc05a553fe9985eedd44f41efde07 100644 (file)
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -26264,7 +26264,8 @@ bool X86TargetLowering::isGAPlusOffset(SDNode *N,
 // instructions.
 // TODO: Investigate sharing more of this with shuffle lowering.
 static bool matchUnaryVectorShuffle(MVT MaskVT, ArrayRef<int> Mask,
-                                    bool FloatDomain,
+                                    bool FloatDomain, SDValue &V1, SDLoc &DL,
+                                    SelectionDAG &DAG,
                                     const X86Subtarget &Subtarget,
                                     unsigned &Shuffle, MVT &SrcVT, MVT &DstVT) {
   unsigned NumMaskElts = Mask.size();
@@ -26280,8 +26281,9 @@ static bool matchUnaryVectorShuffle(MVT MaskVT, ArrayRef<int> Mask,
   }
 
   // Match against a VZEXT instruction.
-  // TODO: Add 256/512-bit vector support.
-  if (!FloatDomain && MaskVT.is128BitVector() && Subtarget.hasSSE41()) {
+  // TODO: Add 512-bit vector support (split AVX512F and AVX512BW).
+  if (!FloatDomain && ((MaskVT.is128BitVector() && Subtarget.hasSSE41()) ||
+                       (MaskVT.is256BitVector() && Subtarget.hasInt256()))) {
     unsigned MaxScale = 64 / MaskEltSize;
     for (unsigned Scale = 2; Scale <= MaxScale; Scale *= 2) {
       bool Match = true;
@@ -26291,7 +26293,10 @@ static bool matchUnaryVectorShuffle(MVT MaskVT, ArrayRef<int> Mask,
         Match &= isUndefOrZeroInRange(Mask, (i * Scale) + 1, Scale - 1);
       }
       if (Match) {
-        SrcVT = MaskVT;
+        unsigned SrcSize = std::max(128u, NumDstElts * MaskEltSize);
+        SrcVT = MVT::getVectorVT(MaskVT.getScalarType(), SrcSize / MaskEltSize);
+        if (SrcVT != MaskVT)
+          V1 = extractSubVector(V1, 0, DAG, DL, SrcSize);
         DstVT = MVT::getIntegerVT(Scale * MaskEltSize);
         DstVT = MVT::getVectorVT(DstVT, NumDstElts);
         Shuffle = X86ISD::VZEXT;
@@ -26908,8 +26913,8 @@ static bool combineX86ShuffleChain(ArrayRef<SDValue> Inputs, SDValue Root,
       }
     }
 
-    if (matchUnaryVectorShuffle(MaskVT, Mask, FloatDomain, Subtarget, Shuffle,
-                                ShuffleSrcVT, ShuffleVT)) {
+    if (matchUnaryVectorShuffle(MaskVT, Mask, FloatDomain, V1, DL, DAG,
+                                Subtarget, Shuffle, ShuffleSrcVT, ShuffleVT)) {
       if (Depth == 1 && Root.getOpcode() == Shuffle)
         return false; // Nothing to do!
       if (IsEVEXShuffle && (NumRootElts != ShuffleVT.getVectorNumElements()))

diff --git a/test/CodeGen/X86/vector-shuffle-combining-avx2.ll b/test/CodeGen/X86/vector-shuffle-combining-avx2.ll
index 2f6267edfceb12858031244932c2a33a2414436a..c9845bf74cfb1878649065da12fc61313a031356 100644 (file)
--- a/test/CodeGen/X86/vector-shuffle-combining-avx2.ll
+++ b/test/CodeGen/X86/vector-shuffle-combining-avx2.ll
@@ -480,14 +480,12 @@ define <8 x float> @combine_permps_as_permpd(<8 x float> %a) {
 define <4 x i64> @combine_pshufb_as_zext(<32 x i8> %a0) {
 ; X32-LABEL: combine_pshufb_as_zext:
 ; X32:       # BB#0:
-; X32-NEXT:    vpermq {{.*#+}} ymm0 = ymm0[1,0,0,1]
-; X32-NEXT:    vpshufb {{.*#+}} ymm0 = ymm0[8,9],zero,zero,zero,zero,zero,zero,ymm0[10,11],zero,zero,zero,zero,zero,zero,ymm0[20,21],zero,zero,zero,zero,zero,zero,ymm0[22,23],zero,zero,zero,zero,zero,zero
+; X32-NEXT:    vpmovzxwq {{.*#+}} ymm0 = xmm0[0],zero,zero,zero,xmm0[1],zero,zero,zero,xmm0[2],zero,zero,zero,xmm0[3],zero,zero,zero
 ; X32-NEXT:    retl
 ;
 ; X64-LABEL: combine_pshufb_as_zext:
 ; X64:       # BB#0:
-; X64-NEXT:    vpermq {{.*#+}} ymm0 = ymm0[1,0,0,1]
-; X64-NEXT:    vpshufb {{.*#+}} ymm0 = ymm0[8,9],zero,zero,zero,zero,zero,zero,ymm0[10,11],zero,zero,zero,zero,zero,zero,ymm0[20,21],zero,zero,zero,zero,zero,zero,ymm0[22,23],zero,zero,zero,zero,zero,zero
+; X64-NEXT:    vpmovzxwq {{.*#+}} ymm0 = xmm0[0],zero,zero,zero,xmm0[1],zero,zero,zero,xmm0[2],zero,zero,zero,xmm0[3],zero,zero,zero
 ; X64-NEXT:    retq
   %1 = shufflevector <32 x i8> %a0, <32 x i8> undef, <32 x i32> <i32 8, i32 9, i32 10, i32 11, i32 12, i32 13, i32 14, i32 15, i32 0, i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7, i32 0, i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7, i32 8, i32 9, i32 10, i32 11, i32 12, i32 13, i32 14, i32 15>
   %2 = call <32 x i8> @llvm.x86.avx2.pshuf.b(<32 x i8> %1, <32 x i8> <i8 8, i8 9, i8 -1, i8 -1, i8 -1, i8 -1, i8 -1, i8 -1, i8 10, i8 11, i8 -1, i8 -1, i8 -1, i8 -1, i8 -1, i8 -1, i8 4, i8 5, i8 -1, i8 -1, i8 -1, i8 -1, i8 -1, i8 -1, i8 6, i8 7, i8 -1, i8 -1, i8 -1, i8 -1, i8 -1, i8 -1>)