[llvm] r271834 - [X86][XOP] Added VPERMIL2PD/VPERMIL2PS raw mask decoding for target shuffle combines

[Simon Pilgrim via llvm-commits]

Author: rksimon
Date: Sun Jun  5 10:21:30 2016
New Revision: 271834

URL: http://llvm.org/viewvc/llvm-project?rev=271834&view=rev
Log:
[X86][XOP] Added VPERMIL2PD/VPERMIL2PS raw mask decoding for target shuffle combines

Modified:
    llvm/trunk/lib/Target/X86/Utils/X86ShuffleDecode.cpp
    llvm/trunk/lib/Target/X86/Utils/X86ShuffleDecode.h
    llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
    llvm/trunk/test/CodeGen/X86/vector-shuffle-combining-xop.ll

Modified: llvm/trunk/lib/Target/X86/Utils/X86ShuffleDecode.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/Utils/X86ShuffleDecode.cpp?rev=271834&r1=271833&r2=271834&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/Utils/X86ShuffleDecode.cpp (original)
+++ llvm/trunk/lib/Target/X86/Utils/X86ShuffleDecode.cpp Sun Jun  5 10:21:30 2016
@@ -512,6 +512,46 @@ void DecodeVPERMILPMask(MVT VT, ArrayRef
   }
 }
 
+void DecodeVPERMIL2PMask(MVT VT, unsigned M2Z, ArrayRef<uint64_t> RawMask,
+                         SmallVectorImpl<int> &ShuffleMask) {
+  unsigned VecSize = VT.getSizeInBits();
+  unsigned EltSize = VT.getScalarSizeInBits();
+  unsigned NumLanes = VecSize / 128;
+  unsigned NumEltsPerLane = VT.getVectorNumElements() / NumLanes;
+  assert((VecSize == 128 || VecSize == 256) &&
+         "Unexpected vector size");
+  assert((EltSize == 32 || EltSize == 64) && "Unexpected element size");
+
+  for (unsigned i = 0, e = RawMask.size(); i < e; ++i) {
+    // VPERMIL2 Operation.
+    // Bits[3] - Match Bit.
+    // Bits[2:1] - (Per Lane) PD Shuffle Mask.
+    // Bits[2:0] - (Per Lane) PS Shuffle Mask.
+    uint64_t Selector = RawMask[i];
+    int MatchBit = (Selector >> 3) & 0x1;
+
+    // M2Z[0:1]     MatchBit
+    //   0Xb           X        Source selected by Selector index.
+    //   10b           0        Source selected by Selector index.
+    //   10b           1        Zero.
+    //   11b           0        Zero.
+    //   11b           1        Source selected by Selector index.
+    if ((M2Z & 0x2) != 0 && MatchBit != (M2Z & 0x1)) {
+      ShuffleMask.push_back(SM_SentinelZero);
+      continue;
+    }
+
+    unsigned Index = i & ~(NumEltsPerLane - 1);
+    if (EltSize == 64)
+      Index += (Selector >> 1) & 0x1;
+    else
+      Index += Selector & 0x3;
+
+    unsigned SrcOffset = (Selector >> 2) & 1;
+    ShuffleMask.push_back((int)(SrcOffset + Index));
+  }
+}
+
 void DecodeVPERMVMask(ArrayRef<uint64_t> RawMask,
                       SmallVectorImpl<int> &ShuffleMask) {
   for (int i = 0, e = RawMask.size(); i < e; ++i) {

Modified: llvm/trunk/lib/Target/X86/Utils/X86ShuffleDecode.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/Utils/X86ShuffleDecode.h?rev=271834&r1=271833&r2=271834&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/Utils/X86ShuffleDecode.h (original)
+++ llvm/trunk/lib/Target/X86/Utils/X86ShuffleDecode.h Sun Jun  5 10:21:30 2016
@@ -138,6 +138,10 @@ void DecodeINSERTQIMask(int Len, int Idx
 void DecodeVPERMILPMask(MVT VT, ArrayRef<uint64_t> RawMask,
                         SmallVectorImpl<int> &ShuffleMask);
 
+/// Decode a VPERMIL2PD/VPERMIL2PS variable mask from a raw array of constants.
+void DecodeVPERMIL2PMask(MVT VT, unsigned M2Z, ArrayRef<uint64_t> RawMask,
+                         SmallVectorImpl<int> &ShuffleMask);
+
 /// Decode a VPERM W/D/Q/PS/PD mask from a raw array of constants.
 void DecodeVPERMVMask(ArrayRef<uint64_t> RawMask,
                       SmallVectorImpl<int> &ShuffleMask);

Modified: llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86ISelLowering.cpp?rev=271834&r1=271833&r2=271834&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86ISelLowering.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86ISelLowering.cpp Sun Jun  5 10:21:30 2016
@@ -4937,6 +4937,11 @@ static bool getTargetShuffleMask(SDNode
     SDValue CtrlNode = N->getOperand(3);
     if (ConstantSDNode *CtrlOp = dyn_cast<ConstantSDNode>(CtrlNode)) {
       unsigned CtrlImm = CtrlOp->getZExtValue();
+      SmallVector<uint64_t, 32> RawMask;
+      if (getTargetShuffleMaskIndices(MaskNode, MaskEltSize, RawMask)) {
+        DecodeVPERMIL2PMask(VT, CtrlImm, RawMask, Mask);
+        break;
+      }
       if (auto *C = getTargetShuffleMaskConstant(MaskNode)) {
         DecodeVPERMIL2PMask(C, CtrlImm, MaskEltSize, Mask);
         break;

Modified: llvm/trunk/test/CodeGen/X86/vector-shuffle-combining-xop.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/vector-shuffle-combining-xop.ll?rev=271834&r1=271833&r2=271834&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/vector-shuffle-combining-xop.ll (original)
+++ llvm/trunk/test/CodeGen/X86/vector-shuffle-combining-xop.ll Sun Jun  5 10:21:30 2016
@@ -13,10 +13,7 @@ declare <16 x i8> @llvm.x86.xop.vpperm(<
 define <2 x double> @combine_vpermil2pd_identity(<2 x double> %a0, <2 x double> %a1) {
 ; CHECK-LABEL: combine_vpermil2pd_identity:
 ; CHECK:       # BB#0:
-; CHECK-NEXT:    movl $2, %eax
-; CHECK-NEXT:    vmovq %rax, %xmm2
-; CHECK-NEXT:    vpermil2pd $0, %xmm2, %xmm0, %xmm1, %xmm0
-; CHECK-NEXT:    vpermil2pd $0, %xmm2, %xmm0, %xmm0, %xmm0
+; CHECK-NEXT:    vmovaps %xmm1, %xmm0
 ; CHECK-NEXT:    retq
   %res0 = call <2 x double> @llvm.x86.xop.vpermil2pd(<2 x double> %a1, <2 x double> %a0, <2 x i64> <i64 2, i64 0>, i8 0)
   %res1 = call <2 x double> @llvm.x86.xop.vpermil2pd(<2 x double> %res0, <2 x double> undef, <2 x i64> <i64 2, i64 0>, i8 0)