Revert r237579, as it broke windows buildbots

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237583 91177308-0d34-0410-b5e6-96231b3b80d8

Author: ostannard

lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp

@@ -4054,9 +4054,10 @@ SelectionDAGBuilder::visitIntrinsicCall(const CallInst &I, unsigned Intrinsic) {
   case Intrinsic::write_register: {
     Value *Reg = I.getArgOperand(0);
     Value *RegValue = I.getArgOperand(1);
+    SDValue Chain = getValue(RegValue).getOperand(0);
     SDValue RegName =
         DAG.getMDNode(cast<MDNode>(cast<MetadataAsValue>(Reg)->getMetadata()));
-    DAG.setRoot(DAG.getNode(ISD::WRITE_REGISTER, sdl, MVT::Other, getRoot(),
+    DAG.setRoot(DAG.getNode(ISD::WRITE_REGISTER, sdl, MVT::Other, Chain,
                             RegName, getValue(RegValue)));
     return nullptr;
   }

lib/Target/AArch64/AArch64ISelDAGToDAG.cpp

@@ -156,9 +156,6 @@ class AArch64DAGToDAGISel : public SelectionDAGISel {
 
   SDNode *SelectLIBM(SDNode *N);
 
-  SDNode *SelectReadRegister(SDNode *N);
-  SDNode *SelectWriteRegister(SDNode *N);
-
 // Include the pieces autogenerated from the target description.
 #include "AArch64GenDAGISel.inc"
 
@@ -2117,115 +2114,6 @@ AArch64DAGToDAGISel::SelectCVTFixedPosOperand(SDValue N, SDValue &FixedPos,
   return true;
 }
 
-// Inspects a register string of the form o0:op1:CRn:CRm:op2 gets the fields
-// of the string and obtains the integer values from them and combines these
-// into a single value to be used in the MRS/MSR instruction.
-static int getIntOperandFromRegisterString(StringRef RegString) {
-  SmallVector<StringRef, 5> Fields;
-  RegString.split(Fields, ":");
-
-  if (Fields.size() == 1)
-    return -1;
-
-  assert(Fields.size() == 5
-            && "Invalid number of fields in read register string");
-
-  SmallVector<int, 5> Ops;
-  bool AllIntFields = true;
-
-  for (StringRef Field : Fields) {
-    unsigned IntField;
-    AllIntFields &= !Field.getAsInteger(10, IntField);
-    Ops.push_back(IntField);
-  }
-
-  assert(AllIntFields &&
-          "Unexpected non-integer value in special register string.");
-
-  // Need to combine the integer fields of the string into a single value
-  // based on the bit encoding of MRS/MSR instruction.
-  return (Ops[0] << 14) | (Ops[1] << 11) | (Ops[2] << 7) |
-         (Ops[3] << 3) | (Ops[4]);
-}
-
-// Lower the read_register intrinsic to an MRS instruction node if the special
-// register string argument is either of the form detailed in the ALCE (the
-// form described in getIntOperandsFromRegsterString) or is a named register
-// known by the MRS SysReg mapper.
-SDNode *AArch64DAGToDAGISel::SelectReadRegister(SDNode *N) {
-  const MDNodeSDNode *MD = dyn_cast<MDNodeSDNode>(N->getOperand(0));
-  const MDString *RegString = dyn_cast<MDString>(MD->getMD()->getOperand(0));
-  SDLoc DL(N);
-
-  int Reg = getIntOperandFromRegisterString(RegString->getString());
-  if (Reg != -1)
-    return CurDAG->getMachineNode(AArch64::MRS, DL, N->getSimpleValueType(0),
-                                  CurDAG->getTargetConstant(Reg, DL, MVT::i32));
-
-  // Use the sysreg mapper to map the remaining possible strings to the
-  // value for the register to be used for the instruction operand.
-  AArch64SysReg::MRSMapper mapper;
-  bool IsValidSpecialReg;
-  Reg = mapper.fromString(RegString->getString(),
-                          Subtarget->getFeatureBits(),
-                          IsValidSpecialReg);
-  if (IsValidSpecialReg)
-    return CurDAG->getMachineNode(AArch64::MRS, DL, N->getSimpleValueType(0),
-                                  CurDAG->getTargetConstant(Reg, DL, MVT::i32));
-  return nullptr;
-}
-
-// Lower the write_register intrinsic to an MSR instruction node if the special
-// register string argument is either of the form detailed in the ALCE (the
-// form described in getIntOperandsFromRegsterString) or is a named register
-// known by the MSR SysReg mapper.
-SDNode *AArch64DAGToDAGISel::SelectWriteRegister(SDNode *N) {
-  const MDNodeSDNode *MD = dyn_cast<MDNodeSDNode>(N->getOperand(1));
-  const MDString *RegString = dyn_cast<MDString>(MD->getMD()->getOperand(0));
-  SDLoc DL(N);
-
-  int Reg = getIntOperandFromRegisterString(RegString->getString());
-  if (Reg != -1)
-    return CurDAG->getMachineNode(AArch64::MSR, DL, MVT::Other,
-                                  CurDAG->getTargetConstant(Reg, DL, MVT::i32),
-                                  N->getOperand(2), N->getOperand(0));
-
-  // Check if the register was one of those allowed as the pstatefield value in
-  // the MSR (immediate) instruction. To accept the values allowed in the
-  // pstatefield for the MSR (immediate) instruction, we also require that an
-  // immediate value has been provided as an argument, we know that this is
-  // the case as it has been ensured by semantic checking.
-  AArch64PState::PStateMapper PMapper;
-  bool IsValidSpecialReg;
-  Reg = PMapper.fromString(RegString->getString(),
-                           Subtarget->getFeatureBits(),
-                           IsValidSpecialReg);
-  if (IsValidSpecialReg) {
-    assert (isa<ConstantSDNode>(N->getOperand(2))
-              && "Expected a constant integer expression.");
-    uint64_t Immed = cast<ConstantSDNode>(N->getOperand(2))->getZExtValue();
-    return CurDAG->getMachineNode(AArch64::MSRpstate, DL, MVT::Other,
-                                  CurDAG->getTargetConstant(Reg, DL, MVT::i32),
-                                  CurDAG->getTargetConstant(Immed, DL, MVT::i16),
-                                  N->getOperand(0));
-  }
-
-  // Use the sysreg mapper to attempt to map the remaining possible strings
-  // to the value for the register to be used for the MSR (register)
-  // instruction operand.
-  AArch64SysReg::MSRMapper Mapper;
-  Reg = Mapper.fromString(RegString->getString(),
-                          Subtarget->getFeatureBits(),
-                          IsValidSpecialReg);
-
-  if (IsValidSpecialReg)
-    return CurDAG->getMachineNode(AArch64::MSR, DL, MVT::Other,
-                                  CurDAG->getTargetConstant(Reg, DL, MVT::i32),
-                                  N->getOperand(2), N->getOperand(0));
-
-  return nullptr;
-}
-
 SDNode *AArch64DAGToDAGISel::Select(SDNode *Node) {
   // Dump information about the Node being selected
   DEBUG(errs() << "Selecting: ");
@@ -2247,16 +2135,6 @@ SDNode *AArch64DAGToDAGISel::Select(SDNode *Node) {
   default:
     break;
 
-  case ISD::READ_REGISTER:
-    if (SDNode *Res = SelectReadRegister(Node))
-      return Res;
-    break;
-
-  case ISD::WRITE_REGISTER:
-    if (SDNode *Res = SelectWriteRegister(Node))
-      return Res;
-    break;
-
   case ISD::ADD:
     if (SDNode *I = SelectMLAV64LaneV128(Node))
       return I;

lib/Target/AArch64/AArch64ISelLowering.cpp

@@ -4064,8 +4064,7 @@ unsigned AArch64TargetLowering::getRegisterByName(const char* RegName,
                        .Default(0);
   if (Reg)
     return Reg;
-  report_fatal_error(Twine("Invalid register name \""
-                              + StringRef(RegName)  + "\"."));
+  report_fatal_error("Invalid register name global variable");
 }
 
 SDValue AArch64TargetLowering::LowerRETURNADDR(SDValue Op,