R600: Add support for vector local memory loads

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@189226 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/R600/AMDGPUISelLowering.cpp b/lib/Target/R600/AMDGPUISelLowering.cpp
index 88867b6..1237323 100644
--- a/lib/Target/R600/AMDGPUISelLowering.cpp
+++ b/lib/Target/R600/AMDGPUISelLowering.cpp
@@ -424,6 +424,29 @@
   return Op;
 }
 
+SDValue AMDGPUTargetLowering::SplitVectorLoad(const SDValue &Op,
+                                              SelectionDAG &DAG) const {
+  LoadSDNode *Load = dyn_cast<LoadSDNode>(Op);
+  EVT MemEltVT = Load->getMemoryVT().getVectorElementType();
+  EVT EltVT = Op.getValueType().getVectorElementType();
+  EVT PtrVT = Load->getBasePtr().getValueType();
+  unsigned NumElts = Load->getMemoryVT().getVectorNumElements();
+  SmallVector<SDValue, 8> Loads;
+  SDLoc SL(Op);
+
+  for (unsigned i = 0, e = NumElts; i != e; ++i) {
+    SDValue Ptr = DAG.getNode(ISD::ADD, SL, PtrVT, Load->getBasePtr(),
+                    DAG.getConstant(i * (MemEltVT.getSizeInBits() / 8), PtrVT));
+    Loads.push_back(DAG.getExtLoad(Load->getExtensionType(), SL, EltVT,
+                        Load->getChain(), Ptr,
+                        MachinePointerInfo(Load->getMemOperand()->getValue()),
+                        MemEltVT, Load->isVolatile(), Load->isNonTemporal(),
+                        Load->getAlignment()));
+  }
+  return DAG.getNode(ISD::BUILD_VECTOR, SL, Op.getValueType(), &Loads[0],
+                     Loads.size());
+}
+
 SDValue AMDGPUTargetLowering::MergeVectorStore(const SDValue &Op,
                                                SelectionDAG &DAG) const {
   StoreSDNode *Store = dyn_cast<StoreSDNode>(Op);
diff --git a/lib/Target/R600/AMDGPUISelLowering.h b/lib/Target/R600/AMDGPUISelLowering.h
index f739aed..75ac4c2 100644
--- a/lib/Target/R600/AMDGPUISelLowering.h
+++ b/lib/Target/R600/AMDGPUISelLowering.h
@@ -50,6 +50,8 @@
                                        unsigned Reg, EVT VT) const;
   SDValue LowerGlobalAddress(AMDGPUMachineFunction *MFI, SDValue Op,
                              SelectionDAG &DAG) const;
+  /// \brief Split a vector load into multiple scalar loads.
+  SDValue SplitVectorLoad(const SDValue &Op, SelectionDAG &DAG) const;
   SDValue LowerSTORE(SDValue Op, SelectionDAG &DAG) const;
   bool isHWTrueValue(SDValue Op) const;
   bool isHWFalseValue(SDValue Op) const;
diff --git a/lib/Target/R600/R600ISelLowering.cpp b/lib/Target/R600/R600ISelLowering.cpp
index 9bc8e8a..f0242b8 100644
--- a/lib/Target/R600/R600ISelLowering.cpp
+++ b/lib/Target/R600/R600ISelLowering.cpp
@@ -1155,6 +1155,14 @@
   SDValue Ptr = Op.getOperand(1);
   SDValue LoweredLoad;
 
+  if (LoadNode->getAddressSpace() == AMDGPUAS::LOCAL_ADDRESS && VT.isVector()) {
+    SDValue MergedValues[2] = {
+      SplitVectorLoad(Op, DAG),
+      Chain
+    };
+    return DAG.getMergeValues(MergedValues, 2, DL);
+  }
+
   int ConstantBlock = ConstantAddressBlock(LoadNode->getAddressSpace());
   if (ConstantBlock > -1) {
     SDValue Result;
diff --git a/lib/Target/R600/SIISelLowering.cpp b/lib/Target/R600/SIISelLowering.cpp
index 9cbba6c..f196059 100644
--- a/lib/Target/R600/SIISelLowering.cpp
+++ b/lib/Target/R600/SIISelLowering.cpp
@@ -66,6 +66,10 @@
 
   setOperationAction(ISD::BITCAST, MVT::i128, Legal);
 
+  // We need to custom lower vector stores from local memory
+  setOperationAction(ISD::LOAD, MVT::v2i32, Custom);
+  setOperationAction(ISD::LOAD, MVT::v4i32, Custom);
+
   setOperationAction(ISD::SELECT_CC, MVT::f32, Custom);
   setOperationAction(ISD::SELECT_CC, MVT::i32, Custom);
 
@@ -368,6 +372,19 @@
   switch (Op.getOpcode()) {
   default: return AMDGPUTargetLowering::LowerOperation(Op, DAG);
   case ISD::BRCOND: return LowerBRCOND(Op, DAG);
+  case ISD::LOAD: {
+    LoadSDNode *Load = dyn_cast<LoadSDNode>(Op);
+    if (Load->getAddressSpace() == AMDGPUAS::LOCAL_ADDRESS &&
+        Op.getValueType().isVector()) {
+      SDValue MergedValues[2] = {
+        SplitVectorLoad(Op, DAG),
+        Load->getChain()
+      };
+      return DAG.getMergeValues(MergedValues, 2, SDLoc(Op));
+    } else {
+      return SDValue();
+    }
+  }
   case ISD::SELECT_CC: return LowerSELECT_CC(Op, DAG);
   case ISD::SIGN_EXTEND: return LowerSIGN_EXTEND(Op, DAG);
   case ISD::ZERO_EXTEND: return LowerZERO_EXTEND(Op, DAG);