Simplified BLEND pattern matching for shuffles.

Generate VPBLENDD for AVX2 and VPBLENDW for v16i16 type on AVX2.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169366 91177308-0d34-0410-b5e6-96231b3b80d8

4 files changed, 68 insertions, 78 deletions

diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index 81e8a7b..b3ff4ee 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -5641,64 +5641,53 @@ LowerVECTOR_SHUFFLEtoBlend(ShuffleVectorSDNode *SVOp,
   SDValue V1 = SVOp->getOperand(0);
   SDValue V2 = SVOp->getOperand(1);
   DebugLoc dl = SVOp->getDebugLoc();
-  MVT VT = SVOp->getValueType(0).getSimpleVT();
+  EVT VT = SVOp->getValueType(0);
+  EVT EltVT = VT.getVectorElementType();
   unsigned NumElems = VT.getVectorNumElements();
 
-  if (!Subtarget->hasSSE41())
+  if (!Subtarget->hasSSE41() || EltVT == MVT::i8)
+    return SDValue();
+  if (!Subtarget->hasInt256() && VT == MVT::v16i16)
     return SDValue();
 
-  unsigned ISDNo = 0;
-  MVT OpTy;
-
-  switch (VT.SimpleTy) {
-  default: return SDValue();
-  case MVT::v8i16:
-    ISDNo = X86ISD::BLENDPW;
-    OpTy = MVT::v8i16;
-    break;
-  case MVT::v4i32:
-  case MVT::v4f32:
-    ISDNo = X86ISD::BLENDPS;
-    OpTy = MVT::v4f32;
-    break;
-  case MVT::v2i64:
-  case MVT::v2f64:
-    ISDNo = X86ISD::BLENDPD;
-    OpTy = MVT::v2f64;
-    break;
-  case MVT::v8i32:
-  case MVT::v8f32:
-    if (!Subtarget->hasFp256())
-      return SDValue();
-    ISDNo = X86ISD::BLENDPS;
-    OpTy = MVT::v8f32;
-    break;
-  case MVT::v4i64:
-  case MVT::v4f64:
-    if (!Subtarget->hasFp256())
-      return SDValue();
-    ISDNo = X86ISD::BLENDPD;
-    OpTy = MVT::v4f64;
-    break;
-  }
-  assert(ISDNo && "Invalid Op Number");
+  // Check the mask for BLEND and build the value.
+  unsigned MaskValue = 0;
+  // There are 2 lanes if (NumElems > 8), and 1 lane otherwise.
+  unsigned NumLanes = (NumElems-1)/8 + 1; 
+  unsigned NumElemsInLane = NumElems / NumLanes;
 
-  unsigned MaskVals = 0;
+  // Blend for v16i16 should be symetric for the both lanes.
+  for (unsigned i = 0; i < NumElemsInLane; ++i) {
 
-  for (unsigned i = 0; i != NumElems; ++i) {
+    int SndLaneEltIdx = (NumLanes == 2) ? 
+      SVOp->getMaskElt(i + NumElemsInLane) : -1;
     int EltIdx = SVOp->getMaskElt(i);
-    if (EltIdx == (int)i || EltIdx < 0)
-      MaskVals |= (1<<i);
-    else if (EltIdx == (int)(i + NumElems))
-      continue; // Bit is set to zero;
-    else
+
+    if ((EltIdx == -1 || EltIdx == (int)i) && 
+        (SndLaneEltIdx == -1 || SndLaneEltIdx == (int)(i + NumElemsInLane)))
+      continue;
+
+    if (((unsigned)EltIdx == (i + NumElems)) && 
+        (SndLaneEltIdx == -1 || 
+         (unsigned)SndLaneEltIdx == i + NumElems + NumElemsInLane))
+      MaskValue |= (1<<i);
+    else 
       return SDValue();
   }
 
-  V1 = DAG.getNode(ISD::BITCAST, dl, OpTy, V1);
-  V2 = DAG.getNode(ISD::BITCAST, dl, OpTy, V2);
-  SDValue Ret =  DAG.getNode(ISDNo, dl, OpTy, V1, V2,
-                             DAG.getConstant(MaskVals, MVT::i32));
+  // Convert i32 vectors to floating point if it is not AVX2.
+  // AVX2 introduced VPBLENDD instruction for 128 and 256-bit vectors.
+  EVT BlendVT = VT;
+  if (EltVT == MVT::i64 || (EltVT == MVT::i32 && !Subtarget->hasInt256())) {
+    BlendVT = EVT::getVectorVT(*DAG.getContext(), 
+                              EVT::getFloatingPointVT(EltVT.getSizeInBits()), 
+                              NumElems);
+    V1 = DAG.getNode(ISD::BITCAST, dl, VT, V1);
+    V2 = DAG.getNode(ISD::BITCAST, dl, VT, V2);
+  }
+  
+  SDValue Ret =  DAG.getNode(X86ISD::BLENDI, dl, BlendVT, V1, V2,
+                             DAG.getConstant(MaskValue, MVT::i32));
   return DAG.getNode(ISD::BITCAST, dl, VT, Ret);
 }
 
@@ -11972,9 +11961,7 @@ const char *X86TargetLowering::getTargetNodeName(unsigned Opcode) const {
   case X86ISD::ANDNP:              return "X86ISD::ANDNP";
   case X86ISD::PSIGN:              return "X86ISD::PSIGN";
   case X86ISD::BLENDV:             return "X86ISD::BLENDV";
-  case X86ISD::BLENDPW:            return "X86ISD::BLENDPW";
-  case X86ISD::BLENDPS:            return "X86ISD::BLENDPS";
-  case X86ISD::BLENDPD:            return "X86ISD::BLENDPD";
+  case X86ISD::BLENDI:             return "X86ISD::BLENDI";
   case X86ISD::HADD:               return "X86ISD::HADD";
   case X86ISD::HSUB:               return "X86ISD::HSUB";
   case X86ISD::FHADD:              return "X86ISD::FHADD";
diff --git a/lib/Target/X86/X86ISelLowering.h b/lib/Target/X86/X86ISelLowering.h
index 2988cee..e830c5f 100644
--- a/lib/Target/X86/X86ISelLowering.h
+++ b/lib/Target/X86/X86ISelLowering.h
@@ -176,13 +176,11 @@ namespace llvm {
       /// PSIGN - Copy integer sign.
       PSIGN,
 
-      /// BLENDV - Blend where the selector is an XMM.
+      /// BLENDV - Blend where the selector is a register.
       BLENDV,
 
-      /// BLENDxx - Blend where the selector is an immediate.
-      BLENDPW,
-      BLENDPS,
-      BLENDPD,
+      /// BLENDI - Blend where the selector is an immediate.
+      BLENDI,
 
       /// HADD - Integer horizontal add.
       HADD,
diff --git a/lib/Target/X86/X86InstrFragmentsSIMD.td b/lib/Target/X86/X86InstrFragmentsSIMD.td
index 73ba001..09ab995 100644
--- a/lib/Target/X86/X86InstrFragmentsSIMD.td
+++ b/lib/Target/X86/X86InstrFragmentsSIMD.td
@@ -187,9 +187,7 @@ def X86VPerm2x128 : SDNode<"X86ISD::VPERM2X128", SDTShuff3OpI>;
 
 def X86VBroadcast : SDNode<"X86ISD::VBROADCAST", SDTVBroadcast>;
 
-def X86Blendpw   : SDNode<"X86ISD::BLENDPW",   SDTBlend>;
-def X86Blendps   : SDNode<"X86ISD::BLENDPS",   SDTBlend>;
-def X86Blendpd   : SDNode<"X86ISD::BLENDPD",   SDTBlend>;
+def X86Blendi    : SDNode<"X86ISD::BLENDI",   SDTBlend>;
 def X86Fmadd     : SDNode<"X86ISD::FMADD",     SDTFma>;
 def X86Fnmadd    : SDNode<"X86ISD::FNMADD",    SDTFma>;
 def X86Fmsub     : SDNode<"X86ISD::FMSUB",     SDTFma>;
diff --git a/lib/Target/X86/X86InstrSSE.td b/lib/Target/X86/X86InstrSSE.td
index 229e8b2..da06bf5 100644
--- a/lib/Target/X86/X86InstrSSE.td
+++ b/lib/Target/X86/X86InstrSSE.td
@@ -6891,31 +6891,31 @@ let Predicates = [HasAVX] in {
                             (v4f64 VR256:$src2))),
             (VBLENDVPDYrr VR256:$src2, VR256:$src1, VR256:$mask)>;
 
-  def : Pat<(v8f32 (X86Blendps (v8f32 VR256:$src1), (v8f32 VR256:$src2),
+  def : Pat<(v8f32 (X86Blendi (v8f32 VR256:$src1), (v8f32 VR256:$src2),
                                (imm:$mask))),
-            (VBLENDPSYrri VR256:$src2, VR256:$src1, imm:$mask)>;
-  def : Pat<(v4f64 (X86Blendpd (v4f64 VR256:$src1), (v4f64 VR256:$src2),
+            (VBLENDPSYrri VR256:$src1, VR256:$src2, imm:$mask)>;
+  def : Pat<(v4f64 (X86Blendi (v4f64 VR256:$src1), (v4f64 VR256:$src2),
                                (imm:$mask))),
-            (VBLENDPDYrri VR256:$src2, VR256:$src1, imm:$mask)>;
+            (VBLENDPDYrri VR256:$src1, VR256:$src2, imm:$mask)>;
 
-  def : Pat<(v8i16 (X86Blendpw (v8i16 VR128:$src1), (v8i16 VR128:$src2),
+  def : Pat<(v8i16 (X86Blendi (v8i16 VR128:$src1), (v8i16 VR128:$src2),
                                (imm:$mask))),
-            (VPBLENDWrri VR128:$src2, VR128:$src1, imm:$mask)>;
-  def : Pat<(v4f32 (X86Blendps (v4f32 VR128:$src1), (v4f32 VR128:$src2),
+            (VPBLENDWrri VR128:$src1, VR128:$src2, imm:$mask)>;
+  def : Pat<(v4f32 (X86Blendi (v4f32 VR128:$src1), (v4f32 VR128:$src2),
                                (imm:$mask))),
-            (VBLENDPSrri VR128:$src2, VR128:$src1, imm:$mask)>;
-  def : Pat<(v2f64 (X86Blendpd (v2f64 VR128:$src1), (v2f64 VR128:$src2),
+            (VBLENDPSrri VR128:$src1, VR128:$src2, imm:$mask)>;
+  def : Pat<(v2f64 (X86Blendi (v2f64 VR128:$src1), (v2f64 VR128:$src2),
                                (imm:$mask))),
-            (VBLENDPDrri VR128:$src2, VR128:$src1, imm:$mask)>;
+            (VBLENDPDrri VR128:$src1, VR128:$src2, imm:$mask)>;
 }
 
 let Predicates = [HasAVX2] in {
   def : Pat<(v32i8 (vselect (v32i8 VR256:$mask), (v32i8 VR256:$src1),
                             (v32i8 VR256:$src2))),
-            (VPBLENDVBYrr VR256:$src2, VR256:$src1, VR256:$mask)>;
-  def : Pat<(v16i16 (X86Blendpw (v16i16 VR256:$src1), (v16i16 VR256:$src2),
+            (VPBLENDVBYrr VR256:$src1, VR256:$src2, VR256:$mask)>;
+  def : Pat<(v16i16 (X86Blendi (v16i16 VR256:$src1), (v16i16 VR256:$src2),
                                (imm:$mask))),
-            (VPBLENDWYrri VR256:$src2, VR256:$src1, imm:$mask)>;
+            (VPBLENDWYrri VR256:$src1, VR256:$src2, imm:$mask)>;
 }
 
 /// SS41I_ternary_int - SSE 4.1 ternary operator
@@ -6979,15 +6979,15 @@ let Predicates = [UseSSE41] in {
                             (v2f64 VR128:$src2))),
             (BLENDVPDrr0 VR128:$src2, VR128:$src1)>;
 
-  def : Pat<(v8i16 (X86Blendpw (v8i16 VR128:$src1), (v8i16 VR128:$src2),
+  def : Pat<(v8i16 (X86Blendi (v8i16 VR128:$src1), (v8i16 VR128:$src2),
                                (imm:$mask))),
-            (PBLENDWrri VR128:$src2, VR128:$src1, imm:$mask)>;
-  def : Pat<(v4f32 (X86Blendps (v4f32 VR128:$src1), (v4f32 VR128:$src2),
+            (PBLENDWrri VR128:$src1, VR128:$src2, imm:$mask)>;
+  def : Pat<(v4f32 (X86Blendi (v4f32 VR128:$src1), (v4f32 VR128:$src2),
                                (imm:$mask))),
-            (BLENDPSrri VR128:$src2, VR128:$src1, imm:$mask)>;
-  def : Pat<(v2f64 (X86Blendpd (v2f64 VR128:$src1), (v2f64 VR128:$src2),
+            (BLENDPSrri VR128:$src1, VR128:$src2, imm:$mask)>;
+  def : Pat<(v2f64 (X86Blendi (v2f64 VR128:$src1), (v2f64 VR128:$src2),
                                (imm:$mask))),
-            (BLENDPDrri VR128:$src2, VR128:$src1, imm:$mask)>;
+            (BLENDPDrri VR128:$src1, VR128:$src2, imm:$mask)>;
 
 }
 
@@ -7873,6 +7873,13 @@ defm VPBLENDDY : AVX2_binop_rmi_int<0x02, "vpblendd", int_x86_avx2_pblendd_256,
                                     VR256, memopv4i64, i256mem>, VEX_L;
 }
 
+def : Pat<(v4i32 (X86Blendi (v4i32 VR128:$src1), (v4i32 VR128:$src2),
+                  imm:$mask)),
+          (VPBLENDDrri VR128:$src1, VR128:$src2, imm:$mask)>;
+def : Pat<(v8i32 (X86Blendi (v8i32 VR256:$src1), (v8i32 VR256:$src2),
+                  imm:$mask)),
+          (VPBLENDDYrri VR256:$src1, VR256:$src2, imm:$mask)>;
+
 //===----------------------------------------------------------------------===//
 // VPBROADCAST - Load from memory and broadcast to all elements of the
 //               destination operand