Combine ISD::EXTLOAD, ISD::SEXTLOAD, ISD::ZEXTLOAD into ISD::LOADX. Add an
extra operand to LOADX to specify the exact value extension type.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@30714 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 1fe1001..5d44cf5 100644
--- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -217,7 +217,7 @@
     SDOperand visitBRCOND(SDNode *N);
     SDOperand visitBR_CC(SDNode *N);
     SDOperand visitLOAD(SDNode *N);
-    SDOperand visitXEXTLOAD(SDNode *N);
+    SDOperand visitLOADX(SDNode *N);
     SDOperand visitSTORE(SDNode *N);
     SDOperand visitINSERT_VECTOR_ELT(SDNode *N);
     SDOperand visitVINSERT_VECTOR_ELT(SDNode *N);
@@ -511,9 +511,7 @@
   case ISD::BRCOND:             return visitBRCOND(N);
   case ISD::BR_CC:              return visitBR_CC(N);
   case ISD::LOAD:               return visitLOAD(N);
-  case ISD::EXTLOAD:
-  case ISD::SEXTLOAD:
-  case ISD::ZEXTLOAD:           return visitXEXTLOAD(N);
+  case ISD::LOADX:              return visitLOADX(N);
   case ISD::STORE:              return visitSTORE(N);
   case ISD::INSERT_VECTOR_ELT:  return visitINSERT_VECTOR_ELT(N);
   case ISD::VINSERT_VECTOR_ELT: return visitVINSERT_VECTOR_ELT(N);
@@ -1082,12 +1080,12 @@
       SimplifyDemandedBits(SDOperand(N, 0)))
     return SDOperand(N, 0);
   // fold (zext_inreg (extload x)) -> (zextload x)
-  if (N0.getOpcode() == ISD::EXTLOAD) {
+  if (ISD::isEXTLoad(N0.Val)) {
     MVT::ValueType EVT = cast<VTSDNode>(N0.getOperand(3))->getVT();
     // If we zero all the possible extended bits, then we can turn this into
     // a zextload if we are running before legalize or the operation is legal.
     if (TLI.MaskedValueIsZero(N1, ~0ULL << MVT::getSizeInBits(EVT)) &&
-        (!AfterLegalize || TLI.isOperationLegal(ISD::ZEXTLOAD, EVT))) {
+        (!AfterLegalize || TLI.isLoadXLegal(ISD::ZEXTLOAD, EVT))) {
       SDOperand ExtLoad = DAG.getExtLoad(ISD::ZEXTLOAD, VT, N0.getOperand(0),
                                          N0.getOperand(1), N0.getOperand(2),
                                          EVT);
@@ -1097,12 +1095,12 @@
     }
   }
   // fold (zext_inreg (sextload x)) -> (zextload x) iff load has one use
-  if (N0.getOpcode() == ISD::SEXTLOAD && N0.hasOneUse()) {
+  if (ISD::isSEXTLoad(N0.Val) && N0.hasOneUse()) {
     MVT::ValueType EVT = cast<VTSDNode>(N0.getOperand(3))->getVT();
     // If we zero all the possible extended bits, then we can turn this into
     // a zextload if we are running before legalize or the operation is legal.
     if (TLI.MaskedValueIsZero(N1, ~0ULL << MVT::getSizeInBits(EVT)) &&
-        (!AfterLegalize || TLI.isOperationLegal(ISD::ZEXTLOAD, EVT))) {
+        (!AfterLegalize || TLI.isLoadXLegal(ISD::ZEXTLOAD, EVT))) {
       SDOperand ExtLoad = DAG.getExtLoad(ISD::ZEXTLOAD, VT, N0.getOperand(0),
                                          N0.getOperand(1), N0.getOperand(2),
                                          EVT);
@@ -1115,8 +1113,8 @@
   // fold (and (load x), 255) -> (zextload x, i8)
   // fold (and (extload x, i16), 255) -> (zextload x, i8)
   if (N1C &&
-      (N0.getOpcode() == ISD::LOAD || N0.getOpcode() == ISD::EXTLOAD ||
-       N0.getOpcode() == ISD::ZEXTLOAD) &&
+      (N0.getOpcode() == ISD::LOAD || ISD::isEXTLoad(N0.Val) ||
+       ISD::isZEXTLoad(N0.Val)) &&
       N0.hasOneUse()) {
     MVT::ValueType EVT, LoadedVT;
     if (N1C->getValue() == 255)
@@ -1131,7 +1129,7 @@
     LoadedVT = N0.getOpcode() == ISD::LOAD ? VT :
                            cast<VTSDNode>(N0.getOperand(3))->getVT();
     if (EVT != MVT::Other && LoadedVT > EVT &&
-        (!AfterLegalize || TLI.isOperationLegal(ISD::ZEXTLOAD, EVT))) {
+        (!AfterLegalize || TLI.isLoadXLegal(ISD::ZEXTLOAD, EVT))) {
       MVT::ValueType PtrType = N0.getOperand(1).getValueType();
       // For big endian targets, we need to add an offset to the pointer to load
       // the correct bytes.  For little endian systems, we merely need to read
@@ -1863,7 +1861,7 @@
   
   // fold (sext (load x)) -> (sext (truncate (sextload x)))
   if (N0.getOpcode() == ISD::LOAD && N0.hasOneUse() &&
-      (!AfterLegalize||TLI.isOperationLegal(ISD::SEXTLOAD, N0.getValueType()))){
+      (!AfterLegalize||TLI.isLoadXLegal(ISD::SEXTLOAD, N0.getValueType()))){
     SDOperand ExtLoad = DAG.getExtLoad(ISD::SEXTLOAD, VT, N0.getOperand(0),
                                        N0.getOperand(1), N0.getOperand(2),
                                        N0.getValueType());
@@ -1875,8 +1873,7 @@
 
   // fold (sext (sextload x)) -> (sext (truncate (sextload x)))
   // fold (sext ( extload x)) -> (sext (truncate (sextload x)))
-  if ((N0.getOpcode() == ISD::SEXTLOAD || N0.getOpcode() == ISD::EXTLOAD) &&
-      N0.hasOneUse()) {
+  if ((ISD::isSEXTLoad(N0.Val) || ISD::isEXTLoad(N0.Val)) && N0.hasOneUse()) {
     MVT::ValueType EVT = cast<VTSDNode>(N0.getOperand(3))->getVT();
     SDOperand ExtLoad = DAG.getExtLoad(ISD::SEXTLOAD, VT, N0.getOperand(0),
                                        N0.getOperand(1), N0.getOperand(2), EVT);
@@ -1929,7 +1926,7 @@
   
   // fold (zext (load x)) -> (zext (truncate (zextload x)))
   if (N0.getOpcode() == ISD::LOAD && N0.hasOneUse() &&
-      (!AfterLegalize||TLI.isOperationLegal(ISD::ZEXTLOAD, N0.getValueType()))){
+      (!AfterLegalize||TLI.isLoadXLegal(ISD::ZEXTLOAD, N0.getValueType()))) {
     SDOperand ExtLoad = DAG.getExtLoad(ISD::ZEXTLOAD, VT, N0.getOperand(0),
                                        N0.getOperand(1), N0.getOperand(2),
                                        N0.getValueType());
@@ -1941,8 +1938,7 @@
 
   // fold (zext (zextload x)) -> (zext (truncate (zextload x)))
   // fold (zext ( extload x)) -> (zext (truncate (zextload x)))
-  if ((N0.getOpcode() == ISD::ZEXTLOAD || N0.getOpcode() == ISD::EXTLOAD) &&
-      N0.hasOneUse()) {
+  if ((ISD::isZEXTLoad(N0.Val) || ISD::isEXTLoad(N0.Val)) && N0.hasOneUse()) {
     MVT::ValueType EVT = cast<VTSDNode>(N0.getOperand(3))->getVT();
     SDOperand ExtLoad = DAG.getExtLoad(ISD::ZEXTLOAD, VT, N0.getOperand(0),
                                        N0.getOperand(1), N0.getOperand(2), EVT);
@@ -1995,7 +1991,7 @@
   
   // fold (aext (load x)) -> (aext (truncate (extload x)))
   if (N0.getOpcode() == ISD::LOAD && N0.hasOneUse() &&
-      (!AfterLegalize||TLI.isOperationLegal(ISD::EXTLOAD, N0.getValueType()))) {
+      (!AfterLegalize||TLI.isLoadXLegal(ISD::EXTLOAD, N0.getValueType()))) {
     SDOperand ExtLoad = DAG.getExtLoad(ISD::EXTLOAD, VT, N0.getOperand(0),
                                        N0.getOperand(1), N0.getOperand(2),
                                        N0.getValueType());
@@ -2008,12 +2004,12 @@
   // fold (aext (zextload x)) -> (aext (truncate (zextload x)))
   // fold (aext (sextload x)) -> (aext (truncate (sextload x)))
   // fold (aext ( extload x)) -> (aext (truncate (extload  x)))
-  if ((N0.getOpcode() == ISD::ZEXTLOAD || N0.getOpcode() == ISD::EXTLOAD ||
-       N0.getOpcode() == ISD::SEXTLOAD) &&
-      N0.hasOneUse()) {
+  if (N0.getOpcode() == ISD::LOADX && N0.hasOneUse()) {
     MVT::ValueType EVT = cast<VTSDNode>(N0.getOperand(3))->getVT();
-    SDOperand ExtLoad = DAG.getExtLoad(N0.getOpcode(), VT, N0.getOperand(0),
-                                       N0.getOperand(1), N0.getOperand(2), EVT);
+    unsigned LType = N0.getConstantOperandVal(4);
+    SDOperand ExtLoad = DAG.getExtLoad((ISD::LoadExtType)LType, VT,
+                                       N0.getOperand(0), N0.getOperand(1),
+                                       N0.getOperand(2), EVT);
     CombineTo(N, ExtLoad);
     CombineTo(N0.Val, DAG.getNode(ISD::TRUNCATE, N0.getValueType(), ExtLoad),
               ExtLoad.getValue(1));
@@ -2063,9 +2059,9 @@
   }
   
   // fold (sext_inreg (extload x)) -> (sextload x)
-  if (N0.getOpcode() == ISD::EXTLOAD && 
+  if (ISD::isEXTLoad(N0.Val) && 
       EVT == cast<VTSDNode>(N0.getOperand(3))->getVT() &&
-      (!AfterLegalize || TLI.isOperationLegal(ISD::SEXTLOAD, EVT))) {
+      (!AfterLegalize || TLI.isLoadXLegal(ISD::SEXTLOAD, EVT))) {
     SDOperand ExtLoad = DAG.getExtLoad(ISD::SEXTLOAD, VT, N0.getOperand(0),
                                        N0.getOperand(1), N0.getOperand(2),
                                        EVT);
@@ -2074,9 +2070,9 @@
     return SDOperand(N, 0);   // Return N so it doesn't get rechecked!
   }
   // fold (sext_inreg (zextload x)) -> (sextload x) iff load has one use
-  if (N0.getOpcode() == ISD::ZEXTLOAD && N0.hasOneUse() &&
+  if (ISD::isZEXTLoad(N0.Val) && N0.hasOneUse() &&
       EVT == cast<VTSDNode>(N0.getOperand(3))->getVT() &&
-      (!AfterLegalize || TLI.isOperationLegal(ISD::SEXTLOAD, EVT))) {
+      (!AfterLegalize || TLI.isLoadXLegal(ISD::SEXTLOAD, EVT))) {
     SDOperand ExtLoad = DAG.getExtLoad(ISD::SEXTLOAD, VT, N0.getOperand(0),
                                        N0.getOperand(1), N0.getOperand(2),
                                        EVT);
@@ -2525,7 +2521,7 @@
   
   // fold (fpext (load x)) -> (fpext (fpround (extload x)))
   if (N0.getOpcode() == ISD::LOAD && N0.hasOneUse() &&
-      (!AfterLegalize||TLI.isOperationLegal(ISD::EXTLOAD, N0.getValueType()))) {
+      (!AfterLegalize||TLI.isLoadXLegal(ISD::EXTLOAD, N0.getValueType()))) {
     SDOperand ExtLoad = DAG.getExtLoad(ISD::EXTLOAD, VT, N0.getOperand(0),
                                        N0.getOperand(1), N0.getOperand(2),
                                        N0.getValueType());
@@ -2666,8 +2662,8 @@
   return SDOperand();
 }
 
-/// visitXEXTLOAD - Handle EXTLOAD/ZEXTLOAD/SEXTLOAD.
-SDOperand DAGCombiner::visitXEXTLOAD(SDNode *N) {
+/// visitLOADX - Handle EXTLOAD/ZEXTLOAD/SEXTLOAD.
+SDOperand DAGCombiner::visitLOADX(SDNode *N) {
   SDOperand Chain    = N->getOperand(0);
   SDOperand Ptr      = N->getOperand(1);
   SDOperand SrcValue = N->getOperand(2);
@@ -3299,9 +3295,7 @@
     // This triggers in things like "select bool X, 10.0, 123.0" after the FP
     // constants have been dropped into the constant pool.
     if ((LHS.getOpcode() == ISD::LOAD ||
-         LHS.getOpcode() == ISD::EXTLOAD ||
-         LHS.getOpcode() == ISD::ZEXTLOAD ||
-         LHS.getOpcode() == ISD::SEXTLOAD) &&
+         LHS.getOpcode() == ISD::LOADX ) &&
         // Token chains must be identical.
         LHS.getOperand(0) == RHS.getOperand(0) &&
         // If this is an EXTLOAD, the VT's must match.
@@ -3326,10 +3320,13 @@
       if (LHS.getOpcode() == ISD::LOAD)
         Load = DAG.getLoad(TheSelect->getValueType(0), LHS.getOperand(0),
                            Addr, LHS.getOperand(2));
-      else
-        Load = DAG.getExtLoad(LHS.getOpcode(), TheSelect->getValueType(0),
+      else {
+        unsigned LType = LHS.getConstantOperandVal(4);
+        Load = DAG.getExtLoad((ISD::LoadExtType)LType,
+                              TheSelect->getValueType(0),
                               LHS.getOperand(0), Addr, LHS.getOperand(2),
                               cast<VTSDNode>(LHS.getOperand(3))->getVT());
+      }
       // Users of the select now use the result of the load.
       CombineTo(TheSelect, Load);
       
diff --git a/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp b/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
index c97e52a..07b72a6 100644
--- a/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
@@ -799,7 +799,7 @@
       if (isDouble && CFP->isExactlyValue((float)CFP->getValue()) &&
           // Only do this if the target has a native EXTLOAD instruction from
           // f32.
-          TLI.isOperationLegal(ISD::EXTLOAD, MVT::f32)) {
+          TLI.isLoadXLegal(ISD::EXTLOAD, MVT::f32)) {
         LLVMC = cast<ConstantFP>(ConstantExpr::getCast(LLVMC, Type::FloatTy));
         VT = MVT::f32;
         Extend = true;
@@ -1372,19 +1372,19 @@
     AddLegalizedOperand(SDOperand(Node, 1), Tmp4);
     return Op.ResNo ? Tmp4 : Tmp3;
   }
-  case ISD::EXTLOAD:
-  case ISD::SEXTLOAD:
-  case ISD::ZEXTLOAD: {
+  case ISD::LOADX: {
     Tmp1 = LegalizeOp(Node->getOperand(0));  // Legalize the chain.
     Tmp2 = LegalizeOp(Node->getOperand(1));  // Legalize the pointer.
 
     MVT::ValueType SrcVT = cast<VTSDNode>(Node->getOperand(3))->getVT();
-    switch (TLI.getOperationAction(Node->getOpcode(), SrcVT)) {
+    unsigned LType = cast<ConstantSDNode>(Node->getOperand(4))->getValue();
+    switch (TLI.getLoadXAction(LType, SrcVT)) {
     default: assert(0 && "This action is not supported yet!");
     case TargetLowering::Promote:
-      assert(SrcVT == MVT::i1 && "Can only promote EXTLOAD from i1 -> i8!");
+      assert(SrcVT == MVT::i1 && "Can only promote LOADX from i1 -> i8!");
       Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2, Node->getOperand(2),
-                                      DAG.getValueType(MVT::i8));
+                                      DAG.getValueType(MVT::i8),
+                                      Node->getOperand(4));
       Tmp1 = Result.getValue(0);
       Tmp2 = Result.getValue(1);
       break;
@@ -1393,7 +1393,7 @@
       // FALLTHROUGH
     case TargetLowering::Legal:
       Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2, Node->getOperand(2),
-                                      Node->getOperand(3));
+                                      Node->getOperand(3), Node->getOperand(4));
       Tmp1 = Result.getValue(0);
       Tmp2 = Result.getValue(1);
       
@@ -1414,14 +1414,13 @@
         Tmp2 = LegalizeOp(Load.getValue(1));
         break;
       }
-      assert(Node->getOpcode() != ISD::EXTLOAD &&
-             "EXTLOAD should always be supported!");
+      assert(LType != ISD::EXTLOAD && "EXTLOAD should always be supported!");
       // Turn the unsupported load into an EXTLOAD followed by an explicit
       // zero/sign extend inreg.
       Result = DAG.getExtLoad(ISD::EXTLOAD, Node->getValueType(0),
                               Tmp1, Tmp2, Node->getOperand(2), SrcVT);
       SDOperand ValRes;
-      if (Node->getOpcode() == ISD::SEXTLOAD)
+      if (LType == ISD::SEXTLOAD)
         ValRes = DAG.getNode(ISD::SIGN_EXTEND_INREG, Result.getValueType(),
                              Result, DAG.getValueType(SrcVT));
       else
@@ -3242,12 +3241,12 @@
     // Remember that we legalized the chain.
     AddLegalizedOperand(Op.getValue(1), LegalizeOp(Result.getValue(1)));
     break;
-  case ISD::SEXTLOAD:
-  case ISD::ZEXTLOAD:
-  case ISD::EXTLOAD:
-    Result = DAG.getExtLoad(Node->getOpcode(), NVT, Node->getOperand(0),
-                            Node->getOperand(1), Node->getOperand(2),
-                            cast<VTSDNode>(Node->getOperand(3))->getVT());
+  case ISD::LOADX:
+    Result =
+      DAG.getExtLoad((ISD::LoadExtType)Node->getConstantOperandVal(4),
+                     NVT, Node->getOperand(0), Node->getOperand(1),
+                     Node->getOperand(2),
+                     cast<VTSDNode>(Node->getOperand(3))->getVT());
     // Remember that we legalized the chain.
     AddLegalizedOperand(Op.getValue(1), LegalizeOp(Result.getValue(1)));
     break;
@@ -4479,10 +4478,11 @@
                      Node->getOperand(1), TH, FH, Node->getOperand(4));
     break;
   }
-  case ISD::SEXTLOAD: {
+  case ISD::LOADX: {
     SDOperand Chain = Node->getOperand(0);
     SDOperand Ptr   = Node->getOperand(1);
     MVT::ValueType EVT = cast<VTSDNode>(Node->getOperand(3))->getVT();
+    unsigned LType = Node->getConstantOperandVal(4);
     
     if (EVT == NVT)
       Lo = DAG.getLoad(NVT, Chain, Ptr, Node->getOperand(2));
@@ -4492,48 +4492,20 @@
     
     // Remember that we legalized the chain.
     AddLegalizedOperand(SDOperand(Node, 1), LegalizeOp(Lo.getValue(1)));
-    
-    // The high part is obtained by SRA'ing all but one of the bits of the lo
-    // part.
-    unsigned LoSize = MVT::getSizeInBits(Lo.getValueType());
-    Hi = DAG.getNode(ISD::SRA, NVT, Lo, DAG.getConstant(LoSize-1,
-                                                       TLI.getShiftAmountTy()));
-    break;
-  }
-  case ISD::ZEXTLOAD: {
-    SDOperand Chain = Node->getOperand(0);
-    SDOperand Ptr   = Node->getOperand(1);
-    MVT::ValueType EVT = cast<VTSDNode>(Node->getOperand(3))->getVT();
-    
-    if (EVT == NVT)
-      Lo = DAG.getLoad(NVT, Chain, Ptr, Node->getOperand(2));
-    else
-      Lo = DAG.getExtLoad(ISD::ZEXTLOAD, NVT, Chain, Ptr, Node->getOperand(2),
-                          EVT);
-    
-    // Remember that we legalized the chain.
-    AddLegalizedOperand(SDOperand(Node, 1), LegalizeOp(Lo.getValue(1)));
 
-    // The high part is just a zero.
-    Hi = DAG.getConstant(0, NVT);
-    break;
-  }
-  case ISD::EXTLOAD: {
-    SDOperand Chain = Node->getOperand(0);
-    SDOperand Ptr   = Node->getOperand(1);
-    MVT::ValueType EVT = cast<VTSDNode>(Node->getOperand(3))->getVT();
-    
-    if (EVT == NVT)
-      Lo = DAG.getLoad(NVT, Chain, Ptr, Node->getOperand(2));
-    else
-      Lo = DAG.getExtLoad(ISD::EXTLOAD, NVT, Chain, Ptr, Node->getOperand(2),
-                          EVT);
-    
-    // Remember that we legalized the chain.
-    AddLegalizedOperand(SDOperand(Node, 1), LegalizeOp(Lo.getValue(1)));
-    
-    // The high part is undefined.
-    Hi = DAG.getNode(ISD::UNDEF, NVT);
+    if (LType == ISD::SEXTLOAD) {
+      // The high part is obtained by SRA'ing all but one of the bits of the lo
+      // part.
+      unsigned LoSize = MVT::getSizeInBits(Lo.getValueType());
+      Hi = DAG.getNode(ISD::SRA, NVT, Lo, DAG.getConstant(LoSize-1,
+                                                          TLI.getShiftAmountTy()));
+    } else if (LType == ISD::ZEXTLOAD) {
+      // The high part is just a zero.
+      Hi = DAG.getConstant(0, NVT);
+    } else /* if (LType == ISD::EXTLOAD) */ {
+      // The high part is undefined.
+      Hi = DAG.getNode(ISD::UNDEF, NVT);
+    }
     break;
   }
   case ISD::ANY_EXTEND:
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index c47852b..dc0d00f 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -1482,11 +1482,12 @@
   return getNode(ISD::VLOAD, getVTList(MVT::Vector, MVT::Other), Ops, 5);
 }
 
-SDOperand SelectionDAG::getExtLoad(unsigned Opcode, MVT::ValueType VT,
+SDOperand SelectionDAG::getExtLoad(ISD::LoadExtType LType, MVT::ValueType VT,
                                    SDOperand Chain, SDOperand Ptr, SDOperand SV,
                                    MVT::ValueType EVT) {
-  SDOperand Ops[] = { Chain, Ptr, SV, getValueType(EVT) };
-  return getNode(Opcode, getVTList(VT, MVT::Other), Ops, 4);
+  SDOperand Ops[] = { Chain, Ptr, SV, getValueType(EVT),
+                      getConstant(LType, MVT::i32) };
+  return getNode(ISD::LOADX, getVTList(VT, MVT::Other), Ops, 5);
 }
 
 SDOperand SelectionDAG::getVAArg(MVT::ValueType VT,
@@ -1586,11 +1587,10 @@
     return getNode(Opcode, VTList.VTs[0], Ops, NumOps);
 
   switch (Opcode) {
-  case ISD::EXTLOAD:
-  case ISD::SEXTLOAD:
-  case ISD::ZEXTLOAD: {
+  case ISD::LOADX: {
     MVT::ValueType EVT = cast<VTSDNode>(Ops[3])->getVT();
-    assert(NumOps == 4 && VTList.NumVTs == 2 && "Bad *EXTLOAD!");
+    unsigned LType = cast<ConstantSDNode>(Ops[4])->getValue();
+    assert(NumOps == 5 && VTList.NumVTs == 2 && "Bad *EXTLOAD!");
     // If they are asking for an extending load from/to the same thing, return a
     // normal load.
     if (VTList.VTs[0] == EVT)
@@ -1602,7 +1602,7 @@
       assert(EVT < VTList.VTs[0] &&
              "Should only be an extending load, not truncating!");
     }
-    assert((Opcode == ISD::EXTLOAD || MVT::isInteger(VTList.VTs[0])) &&
+    assert((LType == ISD::EXTLOAD || MVT::isInteger(VTList.VTs[0])) &&
            "Cannot sign/zero extend a FP/Vector load!");
     assert(MVT::isInteger(VTList.VTs[0]) == MVT::isInteger(EVT) &&
            "Cannot convert from FP to Int or Int -> FP!");
@@ -2365,6 +2365,11 @@
   return false;
 }
 
+uint64_t SDNode::getConstantOperandVal(unsigned Num) const {
+  assert(Num < NumOperands && "Invalid child # of SDNode!");
+  return cast<ConstantSDNode>(OperandList[Num])->getValue();
+}
+
 const char *SDNode::getOperationName(const SelectionDAG *G) const {
   switch (getOpcode()) {
   default:
@@ -2525,9 +2530,7 @@
   case ISD::LOAD:               return "load";
   case ISD::STORE:              return "store";
   case ISD::VLOAD:              return "vload";
-  case ISD::EXTLOAD:            return "extload";
-  case ISD::SEXTLOAD:           return "sextload";
-  case ISD::ZEXTLOAD:           return "zextload";
+  case ISD::LOADX:              return "loadx";
   case ISD::TRUNCSTORE:         return "truncstore";
   case ISD::VAARG:              return "vaarg";
   case ISD::VACOPY:             return "vacopy";
diff --git a/lib/CodeGen/SelectionDAG/TargetLowering.cpp b/lib/CodeGen/SelectionDAG/TargetLowering.cpp
index 10c3a04..d9d7e3e 100644
--- a/lib/CodeGen/SelectionDAG/TargetLowering.cpp
+++ b/lib/CodeGen/SelectionDAG/TargetLowering.cpp
@@ -27,6 +27,7 @@
          "Fixed size array in TargetLowering is not large enough!");
   // All operations default to being supported.
   memset(OpActions, 0, sizeof(OpActions));
+  memset(LoadXActions, 0, sizeof(LoadXActions));
 
   IsLittleEndian = TD->isLittleEndian();
   ShiftAmountTy = SetCCResultTy = PointerTy = getValueType(TD->getIntPtrType());
@@ -550,9 +551,11 @@
     KnownOne  = 0;
     break;
   }
-  case ISD::ZEXTLOAD: {
-    MVT::ValueType VT = cast<VTSDNode>(Op.getOperand(3))->getVT();
-    KnownZero |= ~MVT::getIntVTBitMask(VT) & DemandedMask;
+  case ISD::LOADX: {
+    if (ISD::isZEXTLoad(Op.Val)) {
+      MVT::ValueType VT = cast<VTSDNode>(Op.getOperand(3))->getVT();
+      KnownZero |= ~MVT::getIntVTBitMask(VT) & DemandedMask;
+    }
     break;
   }
   case ISD::ZERO_EXTEND: {
@@ -888,9 +891,11 @@
     KnownOne  = 0;
     return;
   }
-  case ISD::ZEXTLOAD: {
-    MVT::ValueType VT = cast<VTSDNode>(Op.getOperand(3))->getVT();
-    KnownZero |= ~MVT::getIntVTBitMask(VT) & Mask;
+  case ISD::LOADX: {
+    if (ISD::isZEXTLoad(Op.Val)) {
+      MVT::ValueType VT = cast<VTSDNode>(Op.getOperand(3))->getVT();
+      KnownZero |= ~MVT::getIntVTBitMask(VT) & Mask;
+    }
     return;
   }
   case ISD::ZERO_EXTEND: {
@@ -1047,13 +1052,6 @@
   case ISD::AssertZext:
     Tmp = MVT::getSizeInBits(cast<VTSDNode>(Op.getOperand(1))->getVT());
     return VTBits-Tmp;
-
-  case ISD::SEXTLOAD:    // '17' bits known
-    Tmp = MVT::getSizeInBits(cast<VTSDNode>(Op.getOperand(3))->getVT());
-    return VTBits-Tmp+1;
-  case ISD::ZEXTLOAD:    // '16' bits known
-    Tmp = MVT::getSizeInBits(cast<VTSDNode>(Op.getOperand(3))->getVT());
-    return VTBits-Tmp;
     
   case ISD::Constant: {
     uint64_t Val = cast<ConstantSDNode>(Op)->getValue();
@@ -1197,6 +1195,20 @@
     break;
   }
   
+  // Handle LOADX separately here. EXTLOAD case will fallthrough.
+  if (Op.getOpcode() == ISD::LOADX) {
+    unsigned LType = Op.getConstantOperandVal(4);
+    switch (LType) {
+    default: break;
+    case ISD::SEXTLOAD:    // '17' bits known
+      Tmp = MVT::getSizeInBits(cast<VTSDNode>(Op.getOperand(3))->getVT());
+      return VTBits-Tmp+1;
+    case ISD::ZEXTLOAD:    // '16' bits known
+      Tmp = MVT::getSizeInBits(cast<VTSDNode>(Op.getOperand(3))->getVT());
+      return VTBits-Tmp;
+    }
+  }
+
   // Allow the target to implement this method for its nodes.
   if (Op.getOpcode() >= ISD::BUILTIN_OP_END ||
       Op.getOpcode() == ISD::INTRINSIC_WO_CHAIN || 
diff --git a/lib/Target/Alpha/AlphaISelLowering.cpp b/lib/Target/Alpha/AlphaISelLowering.cpp
index cbbad53..f94cfd1 100644
--- a/lib/Target/Alpha/AlphaISelLowering.cpp
+++ b/lib/Target/Alpha/AlphaISelLowering.cpp
@@ -48,20 +48,20 @@
   addRegisterClass(MVT::f64, Alpha::F8RCRegisterClass);
   addRegisterClass(MVT::f32, Alpha::F4RCRegisterClass);
   
+  setLoadXAction(ISD::EXTLOAD, MVT::i1,  Promote);
+  setLoadXAction(ISD::EXTLOAD, MVT::f32, Expand);
+  
+  setLoadXAction(ISD::ZEXTLOAD, MVT::i1,  Promote);
+  setLoadXAction(ISD::ZEXTLOAD, MVT::i32, Expand);
+  
+  setLoadXAction(ISD::SEXTLOAD, MVT::i1,  Promote);
+  setLoadXAction(ISD::SEXTLOAD, MVT::i8,  Expand);
+  setLoadXAction(ISD::SEXTLOAD, MVT::i16, Expand);
+  
   //  setOperationAction(ISD::BRIND,        MVT::i64,   Expand);
   setOperationAction(ISD::BR_CC,        MVT::Other, Expand);
   setOperationAction(ISD::SELECT_CC,    MVT::Other, Expand);
   
-  setOperationAction(ISD::EXTLOAD, MVT::i1,  Promote);
-  setOperationAction(ISD::EXTLOAD, MVT::f32, Expand);
-  
-  setOperationAction(ISD::ZEXTLOAD, MVT::i1,  Promote);
-  setOperationAction(ISD::ZEXTLOAD, MVT::i32, Expand);
-  
-  setOperationAction(ISD::SEXTLOAD, MVT::i1,  Promote);
-  setOperationAction(ISD::SEXTLOAD, MVT::i8,  Expand);
-  setOperationAction(ISD::SEXTLOAD, MVT::i16, Expand);
-  
   setOperationAction(ISD::TRUNCSTORE, MVT::i1, Promote);
 
   setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i1, Expand);
diff --git a/lib/Target/IA64/IA64ISelDAGToDAG.cpp b/lib/Target/IA64/IA64ISelDAGToDAG.cpp
index 8367d24..5add5d6 100644
--- a/lib/Target/IA64/IA64ISelDAGToDAG.cpp
+++ b/lib/Target/IA64/IA64ISelDAGToDAG.cpp
@@ -454,8 +454,7 @@
 */
 
   case ISD::LOAD:
-  case ISD::EXTLOAD: // FIXME: load -1, not 1, for bools?
-  case ISD::ZEXTLOAD: {
+  case ISD::LOADX: { // FIXME: load -1, not 1, for bools?
     SDOperand Chain = N->getOperand(0);
     SDOperand Address = N->getOperand(1);
     AddToISelQueue(Chain);
diff --git a/lib/Target/IA64/IA64ISelLowering.cpp b/lib/Target/IA64/IA64ISelLowering.cpp
index 859530e..f832ea2 100644
--- a/lib/Target/IA64/IA64ISelLowering.cpp
+++ b/lib/Target/IA64/IA64ISelLowering.cpp
@@ -35,6 +35,15 @@
       // register class for predicate registers
       addRegisterClass(MVT::i1, IA64::PRRegisterClass);
 
+      setLoadXAction(ISD::EXTLOAD          , MVT::i1   , Promote);
+
+      setLoadXAction(ISD::ZEXTLOAD         , MVT::i1   , Expand);
+
+      setLoadXAction(ISD::SEXTLOAD         , MVT::i1   , Expand);
+      setLoadXAction(ISD::SEXTLOAD         , MVT::i8   , Expand);
+      setLoadXAction(ISD::SEXTLOAD         , MVT::i16  , Expand);
+      setLoadXAction(ISD::SEXTLOAD         , MVT::i32  , Expand);
+
       setOperationAction(ISD::BRIND            , MVT::i64,   Expand);
       setOperationAction(ISD::BR_CC            , MVT::Other, Expand);
       setOperationAction(ISD::FP_ROUND_INREG   , MVT::f32  , Expand);
@@ -50,15 +59,6 @@
       setSetCCResultType(MVT::i1);
       setShiftAmountType(MVT::i64);
 
-      setOperationAction(ISD::EXTLOAD          , MVT::i1   , Promote);
-
-      setOperationAction(ISD::ZEXTLOAD         , MVT::i1   , Expand);
-
-      setOperationAction(ISD::SEXTLOAD         , MVT::i1   , Expand);
-      setOperationAction(ISD::SEXTLOAD         , MVT::i8   , Expand);
-      setOperationAction(ISD::SEXTLOAD         , MVT::i16  , Expand);
-      setOperationAction(ISD::SEXTLOAD         , MVT::i32  , Expand);
-
       setOperationAction(ISD::FREM             , MVT::f32  , Expand);
       setOperationAction(ISD::FREM             , MVT::f64  , Expand);
 
diff --git a/lib/Target/PowerPC/PPCISelLowering.cpp b/lib/Target/PowerPC/PPCISelLowering.cpp
index ffb4617..e96982d 100644
--- a/lib/Target/PowerPC/PPCISelLowering.cpp
+++ b/lib/Target/PowerPC/PPCISelLowering.cpp
@@ -43,6 +43,10 @@
   addRegisterClass(MVT::f32, PPC::F4RCRegisterClass);
   addRegisterClass(MVT::f64, PPC::F8RCRegisterClass);
   
+  // PowerPC has an i16 but no i8 (or i1) SEXTLOAD
+  setLoadXAction(ISD::SEXTLOAD, MVT::i1, Expand);
+  setLoadXAction(ISD::SEXTLOAD, MVT::i8, Expand);
+  
   setOperationAction(ISD::ConstantFP, MVT::f64, Expand);
   setOperationAction(ISD::ConstantFP, MVT::f32, Expand);
 
@@ -51,10 +55,6 @@
   setOperationAction(ISD::MEMSET, MVT::Other, Expand);
   setOperationAction(ISD::MEMCPY, MVT::Other, Expand);
   
-  // PowerPC has an i16 but no i8 (or i1) SEXTLOAD
-  setOperationAction(ISD::SEXTLOAD, MVT::i1, Expand);
-  setOperationAction(ISD::SEXTLOAD, MVT::i8, Expand);
-  
   // PowerPC has no SREM/UREM instructions
   setOperationAction(ISD::SREM, MVT::i32, Expand);
   setOperationAction(ISD::UREM, MVT::i32, Expand);
@@ -311,7 +311,7 @@
 static bool isFloatingPointZero(SDOperand Op) {
   if (ConstantFPSDNode *CFP = dyn_cast<ConstantFPSDNode>(Op))
     return CFP->isExactlyValue(-0.0) || CFP->isExactlyValue(0.0);
-  else if (Op.getOpcode() == ISD::EXTLOAD || Op.getOpcode() == ISD::LOAD) {
+  else if (ISD::isEXTLoad(Op.Val) || Op.getOpcode() == ISD::LOAD) {
     // Maybe this has already been legalized into the constant pool?
     if (ConstantPoolSDNode *CP = dyn_cast<ConstantPoolSDNode>(Op.getOperand(1)))
       if (ConstantFP *CFP = dyn_cast<ConstantFP>(CP->getConstVal()))
diff --git a/lib/Target/Sparc/SparcISelDAGToDAG.cpp b/lib/Target/Sparc/SparcISelDAGToDAG.cpp
index 1d1b595..801cf4e 100644
--- a/lib/Target/Sparc/SparcISelDAGToDAG.cpp
+++ b/lib/Target/Sparc/SparcISelDAGToDAG.cpp
@@ -137,6 +137,9 @@
   addRegisterClass(MVT::f32, SP::FPRegsRegisterClass);
   addRegisterClass(MVT::f64, SP::DFPRegsRegisterClass);
 
+  // Turn FP extload into load/fextend
+  setLoadXAction(ISD::EXTLOAD, MVT::f32, Expand);
+  
   // Custom legalize GlobalAddress nodes into LO/HI parts.
   setOperationAction(ISD::GlobalAddress, MVT::i32, Custom);
   setOperationAction(ISD::ConstantPool , MVT::i32, Custom);
@@ -161,9 +164,6 @@
   setOperationAction(ISD::BIT_CONVERT, MVT::f32, Expand);
   setOperationAction(ISD::BIT_CONVERT, MVT::i32, Expand);
   
-  // Turn FP extload into load/fextend
-  setOperationAction(ISD::EXTLOAD, MVT::f32, Expand);
-  
   // Sparc has no select or setcc: expand to SELECT_CC.
   setOperationAction(ISD::SELECT, MVT::i32, Expand);
   setOperationAction(ISD::SELECT, MVT::f32, Expand);
@@ -332,7 +332,7 @@
         if (ObjectVT == MVT::i32) {
           Load = DAG.getLoad(MVT::i32, Root, FIPtr, DAG.getSrcValue(0));
         } else {
-          unsigned LoadOp =
+          ISD::LoadExtType LoadOp =
             I->getType()->isSigned() ? ISD::SEXTLOAD : ISD::ZEXTLOAD;
 
           // Sparc is big endian, so add an offset based on the ObjectVT.
diff --git a/lib/Target/TargetSelectionDAG.td b/lib/Target/TargetSelectionDAG.td
index f6d4cd5..2a2bd17 100644
--- a/lib/Target/TargetSelectionDAG.td
+++ b/lib/Target/TargetSelectionDAG.td
@@ -164,10 +164,10 @@
   SDTCisPtrTy<1>  
 ]>;
 
-def SDTExtLoad : SDTypeProfile<1, 3, [  // extload
-  SDTCisPtrTy<1>, SDTCisVT<2, OtherVT>, SDTCisVT<3, OtherVT>
+def SDTLoadX : SDTypeProfile<1, 4, [  // loadX
+  SDTCisPtrTy<1>, SDTCisVT<2, OtherVT>, SDTCisVT<3, OtherVT>, SDTCisVT<4, i32>
 ]>;
-def SDTIntExtLoad : SDTypeProfile<1, 3, [  // sextload, zextload
+def SDTIntExtLoad : SDTypeProfile<1, 3, [  // extload, sextload, zextload
   SDTCisInt<0>, SDTCisPtrTy<1>, SDTCisVT<2, OtherVT>, SDTCisVT<3, OtherVT>
 ]>;
 def SDTTruncStore : SDTypeProfile<0, 4, [  // truncstore
@@ -308,11 +308,9 @@
 def load       : SDNode<"ISD::LOAD"       , SDTLoad,  [SDNPHasChain]>;
 def store      : SDNode<"ISD::STORE"      , SDTStore, [SDNPHasChain]>;
 
-// Do not use sextld and zextld directly. Use sextload and zextload (see
-// below) which pass in a dummy srcvalue node which tblgen will skip over.
-def sextld     : SDNode<"ISD::SEXTLOAD"   , SDTIntExtLoad, [SDNPHasChain]>;
-def zextld     : SDNode<"ISD::ZEXTLOAD"   , SDTIntExtLoad, [SDNPHasChain]>;
-def extld      : SDNode<"ISD::EXTLOAD"    , SDTExtLoad,    [SDNPHasChain]>;
+// Do not use loadx directly. Use extload, sextload and zextload (see below)
+// which pass in a dummy srcvalue node which tblgen will skip over.
+def loadx      : SDNode<"ISD::LOADX"      , SDTLoadX,      [SDNPHasChain]>;
 def truncst    : SDNode<"ISD::TRUNCSTORE" , SDTTruncStore, [SDNPHasChain]>;
 
 def vector_shuffle : SDNode<"ISD::VECTOR_SHUFFLE", SDTVecShuffle, []>;
@@ -415,12 +413,12 @@
 def ineg : PatFrag<(ops node:$in), (sub 0, node:$in)>;
 
 // extending load & truncstore fragments.
-def sextload      : PatFrag<(ops node:$ptr, node:$vt),
-                            (sextld node:$ptr, srcvalue:$dummy, node:$vt)>;
-def zextload      : PatFrag<(ops node:$ptr, node:$vt),
-                            (zextld node:$ptr, srcvalue:$dummy, node:$vt)>;
 def extload       : PatFrag<(ops node:$ptr, node:$vt),
-                            (extld node:$ptr, srcvalue:$dummy, node:$vt)>;
+                            (loadx node:$ptr, srcvalue:$dummy, node:$vt, 0)>;
+def sextload      : PatFrag<(ops node:$ptr, node:$vt),
+                            (loadx node:$ptr, srcvalue:$dummy, node:$vt, 1)>;
+def zextload      : PatFrag<(ops node:$ptr, node:$vt),
+                            (loadx node:$ptr, srcvalue:$dummy, node:$vt, 2)>;
 def truncstore    : PatFrag<(ops node:$val, node:$ptr, node:$vt),
                             (truncst node:$val, node:$ptr, srcvalue:$dummy, 
                             node:$vt)>;
diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index 24fe64d..6ab7c98 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -75,6 +75,8 @@
   if (Subtarget->is64Bit())
     addRegisterClass(MVT::i64, X86::GR64RegisterClass);
 
+  setLoadXAction(ISD::SEXTLOAD, MVT::i1, Expand);
+
   // Promote all UINT_TO_FP to larger SINT_TO_FP's, as X86 doesn't have this
   // operation.
   setOperationAction(ISD::UINT_TO_FP       , MVT::i1   , Promote);
@@ -155,7 +157,6 @@
   setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i8   , Expand);
   setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i1   , Expand);
   setOperationAction(ISD::FP_ROUND_INREG   , MVT::f32  , Expand);
-  setOperationAction(ISD::SEXTLOAD         , MVT::i1   , Expand);
   setOperationAction(ISD::FREM             , MVT::f64  , Expand);
 
   setOperationAction(ISD::CTPOP            , MVT::i8   , Expand);