- Use a faster priority comparison function if -fast.
- Code clean up.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53010 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/ScheduleDAG.cpp b/lib/CodeGen/SelectionDAG/ScheduleDAG.cpp
index de2c1bc..b5889fc 100644
--- a/lib/CodeGen/SelectionDAG/ScheduleDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/ScheduleDAG.cpp
@@ -224,26 +224,26 @@
   if (InstrItins.isEmpty()) {
     // No latency information.
     SU->Latency = 1;
-  } else {
-    SU->Latency = 0;
-    if (SU->Node->isTargetOpcode()) {
-      unsigned SchedClass =
-        TII->get(SU->Node->getTargetOpcode()).getSchedClass();
+    return;
+  }
+
+  SU->Latency = 0;
+  if (SU->Node->isTargetOpcode()) {
+    unsigned SchedClass = TII->get(SU->Node->getTargetOpcode()).getSchedClass();
+    const InstrStage *S = InstrItins.begin(SchedClass);
+    const InstrStage *E = InstrItins.end(SchedClass);
+    for (; S != E; ++S)
+      SU->Latency += S->Cycles;
+  }
+  for (unsigned i = 0, e = SU->FlaggedNodes.size(); i != e; ++i) {
+    SDNode *FNode = SU->FlaggedNodes[i];
+    if (FNode->isTargetOpcode()) {
+      unsigned SchedClass = TII->get(FNode->getTargetOpcode()).getSchedClass();
       const InstrStage *S = InstrItins.begin(SchedClass);
       const InstrStage *E = InstrItins.end(SchedClass);
       for (; S != E; ++S)
         SU->Latency += S->Cycles;
     }
-    for (unsigned i = 0, e = SU->FlaggedNodes.size(); i != e; ++i) {
-      SDNode *FNode = SU->FlaggedNodes[i];
-      if (FNode->isTargetOpcode()) {
-        unsigned SchedClass =TII->get(FNode->getTargetOpcode()).getSchedClass();
-        const InstrStage *S = InstrItins.begin(SchedClass);
-        const InstrStage *E = InstrItins.end(SchedClass);
-        for (; S != E; ++S)
-          SU->Latency += S->Cycles;
-      }
-    }
   }
 }
 
@@ -390,11 +390,12 @@
   return N;
 }
 
-static const TargetRegisterClass *getInstrOperandRegClass(
-        const TargetRegisterInfo *TRI, 
-        const TargetInstrInfo *TII,
-        const TargetInstrDesc &II,
-        unsigned Op) {
+/// getInstrOperandRegClass - Return register class of the operand of an
+/// instruction of the specified TargetInstrDesc.
+static const TargetRegisterClass*
+getInstrOperandRegClass(const TargetRegisterInfo *TRI, 
+                        const TargetInstrInfo *TII, const TargetInstrDesc &II,
+                        unsigned Op) {
   if (Op >= II.getNumOperands()) {
     assert(II.isVariadic() && "Invalid operand # of instruction");
     return NULL;
@@ -404,6 +405,8 @@
   return TRI->getRegClass(II.OpInfo[Op].RegClass);
 }
 
+/// EmitCopyFromReg - Generate machine code for an CopyFromReg node or an
+/// implicit physical register output.
 void ScheduleDAG::EmitCopyFromReg(SDNode *Node, unsigned ResNo,
                                   bool IsClone, unsigned SrcReg,
                                   DenseMap<SDOperand, unsigned> &VRBaseMap) {
@@ -660,18 +663,17 @@
       assert(getInstrOperandRegClass(TRI, TII, *II, IIOpNum) &&
              "Don't have operand info for this instruction!");
     }
-  }
-  
+  }  
 }
 
 void ScheduleDAG::AddMemOperand(MachineInstr *MI, const MachineMemOperand &MO) {
   MI->addMemOperand(MO);
 }
 
-// Returns the Register Class of a subregister
-static const TargetRegisterClass *getSubRegisterRegClass(
-        const TargetRegisterClass *TRC,
-        unsigned SubIdx) {
+/// getSubRegisterRegClass - Returns the register class of specified register
+/// class' "SubIdx"'th sub-register class.
+static const TargetRegisterClass*
+getSubRegisterRegClass(const TargetRegisterClass *TRC, unsigned SubIdx) {
   // Pick the register class of the subregister
   TargetRegisterInfo::regclass_iterator I =
     TRC->subregclasses_begin() + SubIdx-1;
@@ -680,10 +682,12 @@
   return *I;
 }
 
-static const TargetRegisterClass *getSuperregRegisterClass(
-        const TargetRegisterClass *TRC,
-        unsigned SubIdx,
-        MVT VT) {
+/// getSuperRegisterRegClass - Returns the register class of a superreg A whose
+/// "SubIdx"'th sub-register class is the specified register class and whose
+/// type matches the specified type.
+static const TargetRegisterClass*
+getSuperRegisterRegClass(const TargetRegisterClass *TRC,
+                         unsigned SubIdx, MVT VT) {
   // Pick the register class of the superegister for this type
   for (TargetRegisterInfo::regclass_iterator I = TRC->superregclasses_begin(),
          E = TRC->superregclasses_end(); I != E; ++I)
@@ -758,7 +762,7 @@
     if (VRBase) {
       TRC = MRI.getRegClass(VRBase);
     } else {
-      TRC = getSuperregRegisterClass(MRI.getRegClass(SubReg), SubIdx, 
+      TRC = getSuperRegisterRegClass(MRI.getRegClass(SubReg), SubIdx, 
                                      Node->getValueType(0));
       assert(TRC && "Couldn't determine register class for insert_subreg");
       VRBase = MRI.createVirtualRegister(TRC); // Create the reg
@@ -867,124 +871,125 @@
           EmitCopyFromReg(Node, i, IsClone, Reg, VRBaseMap);
       }
     }
-  } else {
-    switch (Node->getOpcode()) {
-    default:
+    return;
+  }
+
+  switch (Node->getOpcode()) {
+  default:
 #ifndef NDEBUG
-      Node->dump(&DAG);
+    Node->dump(&DAG);
 #endif
-      assert(0 && "This target-independent node should have been selected!");
-      break;
-    case ISD::EntryToken:
-      assert(0 && "EntryToken should have been excluded from the schedule!");
-      break;
-    case ISD::TokenFactor: // fall thru
-    case ISD::DECLARE:
-    case ISD::SRCVALUE:
-      break;
-    case ISD::DBG_LABEL:
-      BB->push_back(BuildMI(TII->get(TargetInstrInfo::DBG_LABEL))
-                      .addImm(cast<LabelSDNode>(Node)->getLabelID()));
-      break;
-    case ISD::EH_LABEL:
-      BB->push_back(BuildMI(TII->get(TargetInstrInfo::EH_LABEL))
-                      .addImm(cast<LabelSDNode>(Node)->getLabelID()));
-      break;
-    case ISD::CopyToReg: {
-      unsigned SrcReg;
-      SDOperand SrcVal = Node->getOperand(2);
-      if (RegisterSDNode *R = dyn_cast<RegisterSDNode>(SrcVal))
-        SrcReg = R->getReg();
-      else
-        SrcReg = getVR(SrcVal, VRBaseMap);
+    assert(0 && "This target-independent node should have been selected!");
+    break;
+  case ISD::EntryToken:
+    assert(0 && "EntryToken should have been excluded from the schedule!");
+    break;
+  case ISD::TokenFactor: // fall thru
+  case ISD::DECLARE:
+  case ISD::SRCVALUE:
+    break;
+  case ISD::DBG_LABEL:
+    BB->push_back(BuildMI(TII->get(TargetInstrInfo::DBG_LABEL))
+                  .addImm(cast<LabelSDNode>(Node)->getLabelID()));
+    break;
+  case ISD::EH_LABEL:
+    BB->push_back(BuildMI(TII->get(TargetInstrInfo::EH_LABEL))
+                  .addImm(cast<LabelSDNode>(Node)->getLabelID()));
+    break;
+  case ISD::CopyToReg: {
+    unsigned SrcReg;
+    SDOperand SrcVal = Node->getOperand(2);
+    if (RegisterSDNode *R = dyn_cast<RegisterSDNode>(SrcVal))
+      SrcReg = R->getReg();
+    else
+      SrcReg = getVR(SrcVal, VRBaseMap);
       
-      unsigned DestReg = cast<RegisterSDNode>(Node->getOperand(1))->getReg();
-      if (SrcReg == DestReg) // Coalesced away the copy? Ignore.
-        break;
+    unsigned DestReg = cast<RegisterSDNode>(Node->getOperand(1))->getReg();
+    if (SrcReg == DestReg) // Coalesced away the copy? Ignore.
+      break;
       
-      const TargetRegisterClass *SrcTRC = 0, *DstTRC = 0;
-      // Get the register classes of the src/dst.
-      if (TargetRegisterInfo::isVirtualRegister(SrcReg))
-        SrcTRC = MRI.getRegClass(SrcReg);
-      else
-        SrcTRC = TRI->getPhysicalRegisterRegClass(SrcReg,SrcVal.getValueType());
+    const TargetRegisterClass *SrcTRC = 0, *DstTRC = 0;
+    // Get the register classes of the src/dst.
+    if (TargetRegisterInfo::isVirtualRegister(SrcReg))
+      SrcTRC = MRI.getRegClass(SrcReg);
+    else
+      SrcTRC = TRI->getPhysicalRegisterRegClass(SrcReg,SrcVal.getValueType());
 
-      if (TargetRegisterInfo::isVirtualRegister(DestReg))
-        DstTRC = MRI.getRegClass(DestReg);
-      else
-        DstTRC = TRI->getPhysicalRegisterRegClass(DestReg,
+    if (TargetRegisterInfo::isVirtualRegister(DestReg))
+      DstTRC = MRI.getRegClass(DestReg);
+    else
+      DstTRC = TRI->getPhysicalRegisterRegClass(DestReg,
                                             Node->getOperand(1).getValueType());
-      TII->copyRegToReg(*BB, BB->end(), DestReg, SrcReg, DstTRC, SrcTRC);
-      break;
-    }
-    case ISD::CopyFromReg: {
-      unsigned SrcReg = cast<RegisterSDNode>(Node->getOperand(1))->getReg();
-      EmitCopyFromReg(Node, 0, IsClone, SrcReg, VRBaseMap);
-      break;
-    }
-    case ISD::INLINEASM: {
-      unsigned NumOps = Node->getNumOperands();
-      if (Node->getOperand(NumOps-1).getValueType() == MVT::Flag)
-        --NumOps;  // Ignore the flag operand.
+    TII->copyRegToReg(*BB, BB->end(), DestReg, SrcReg, DstTRC, SrcTRC);
+    break;
+  }
+  case ISD::CopyFromReg: {
+    unsigned SrcReg = cast<RegisterSDNode>(Node->getOperand(1))->getReg();
+    EmitCopyFromReg(Node, 0, IsClone, SrcReg, VRBaseMap);
+    break;
+  }
+  case ISD::INLINEASM: {
+    unsigned NumOps = Node->getNumOperands();
+    if (Node->getOperand(NumOps-1).getValueType() == MVT::Flag)
+      --NumOps;  // Ignore the flag operand.
       
-      // Create the inline asm machine instruction.
-      MachineInstr *MI = BuildMI(TII->get(TargetInstrInfo::INLINEASM));
+    // Create the inline asm machine instruction.
+    MachineInstr *MI = BuildMI(TII->get(TargetInstrInfo::INLINEASM));
 
-      // Add the asm string as an external symbol operand.
-      const char *AsmStr =
-        cast<ExternalSymbolSDNode>(Node->getOperand(1))->getSymbol();
-      MI->addOperand(MachineOperand::CreateES(AsmStr));
+    // Add the asm string as an external symbol operand.
+    const char *AsmStr =
+      cast<ExternalSymbolSDNode>(Node->getOperand(1))->getSymbol();
+    MI->addOperand(MachineOperand::CreateES(AsmStr));
       
-      // Add all of the operand registers to the instruction.
-      for (unsigned i = 2; i != NumOps;) {
-        unsigned Flags = cast<ConstantSDNode>(Node->getOperand(i))->getValue();
-        unsigned NumVals = Flags >> 3;
+    // Add all of the operand registers to the instruction.
+    for (unsigned i = 2; i != NumOps;) {
+      unsigned Flags = cast<ConstantSDNode>(Node->getOperand(i))->getValue();
+      unsigned NumVals = Flags >> 3;
         
-        MI->addOperand(MachineOperand::CreateImm(Flags));
-        ++i;  // Skip the ID value.
+      MI->addOperand(MachineOperand::CreateImm(Flags));
+      ++i;  // Skip the ID value.
         
-        switch (Flags & 7) {
-        default: assert(0 && "Bad flags!");
-        case 1:  // Use of register.
-          for (; NumVals; --NumVals, ++i) {
-            unsigned Reg = cast<RegisterSDNode>(Node->getOperand(i))->getReg();
-            MI->addOperand(MachineOperand::CreateReg(Reg, false));
-          }
-          break;
-        case 2:   // Def of register.
-          for (; NumVals; --NumVals, ++i) {
-            unsigned Reg = cast<RegisterSDNode>(Node->getOperand(i))->getReg();
-            MI->addOperand(MachineOperand::CreateReg(Reg, true));
-          }
-          break;
-        case 3: { // Immediate.
-          for (; NumVals; --NumVals, ++i) {
-            if (ConstantSDNode *CS =
-                   dyn_cast<ConstantSDNode>(Node->getOperand(i))) {
-              MI->addOperand(MachineOperand::CreateImm(CS->getValue()));
-            } else if (GlobalAddressSDNode *GA = 
-                  dyn_cast<GlobalAddressSDNode>(Node->getOperand(i))) {
-              MI->addOperand(MachineOperand::CreateGA(GA->getGlobal(),
-                                                      GA->getOffset()));
-            } else {
-              BasicBlockSDNode *BB =cast<BasicBlockSDNode>(Node->getOperand(i));
-              MI->addOperand(MachineOperand::CreateMBB(BB->getBasicBlock()));
-            }
-          }
-          break;
+      switch (Flags & 7) {
+      default: assert(0 && "Bad flags!");
+      case 1:  // Use of register.
+        for (; NumVals; --NumVals, ++i) {
+          unsigned Reg = cast<RegisterSDNode>(Node->getOperand(i))->getReg();
+          MI->addOperand(MachineOperand::CreateReg(Reg, false));
         }
-        case 4:  // Addressing mode.
-          // The addressing mode has been selected, just add all of the
-          // operands to the machine instruction.
-          for (; NumVals; --NumVals, ++i)
-            AddOperand(MI, Node->getOperand(i), 0, 0, VRBaseMap);
-          break;
+        break;
+      case 2:   // Def of register.
+        for (; NumVals; --NumVals, ++i) {
+          unsigned Reg = cast<RegisterSDNode>(Node->getOperand(i))->getReg();
+          MI->addOperand(MachineOperand::CreateReg(Reg, true));
         }
+        break;
+      case 3: { // Immediate.
+        for (; NumVals; --NumVals, ++i) {
+          if (ConstantSDNode *CS =
+              dyn_cast<ConstantSDNode>(Node->getOperand(i))) {
+            MI->addOperand(MachineOperand::CreateImm(CS->getValue()));
+          } else if (GlobalAddressSDNode *GA = 
+                     dyn_cast<GlobalAddressSDNode>(Node->getOperand(i))) {
+            MI->addOperand(MachineOperand::CreateGA(GA->getGlobal(),
+                                                    GA->getOffset()));
+          } else {
+            BasicBlockSDNode *BB =cast<BasicBlockSDNode>(Node->getOperand(i));
+            MI->addOperand(MachineOperand::CreateMBB(BB->getBasicBlock()));
+          }
+        }
+        break;
       }
-      BB->push_back(MI);
-      break;
+      case 4:  // Addressing mode.
+        // The addressing mode has been selected, just add all of the
+        // operands to the machine instruction.
+        for (; NumVals; --NumVals, ++i)
+          AddOperand(MI, Node->getOperand(i), 0, 0, VRBaseMap);
+        break;
+      }
     }
-    }
+    BB->push_back(MI);
+    break;
+  }
   }
 }