[AVR] Remove debug location of spill/reload instructions

[Miss_Grape]

Refer to D128806 D52125

[MatzeB]

I'm probably the wrong reviewer for the AVR target. But I agree that spills/reload instructions are compiler-generated without relation to the source-code being compiled and would be better off without debug locations.

[MatzeB]

This change is straightforward enough. LGTM

llvm/lib/Target/AVR/AVRInstrInfo.cpp

void AVRInstrInfo::storeRegToStackSlot(MachineBasicBlock &MBB,
                                        int FrameIndex,
                                        const TargetRegisterClass *RC,
                                        const TargetRegisterInfo *TRI) const {
   MachineFunction &MF = *MBB.getParent();
   AVRMachineFunctionInfo *AFI = MF.getInfo<AVRMachineFunctionInfo>();
 
   AFI->setHasSpills(true);
 
-  DebugLoc DL;
-  if (MI != MBB.end()) {
-    DL = MI->getDebugLoc();
-  }
-
   const MachineFrameInfo &MFI = MF.getFrameInfo();
 
   MachineMemOperand *MMO = MF.getMachineMemOperand(
       MachinePointerInfo::getFixedStack(MF, FrameIndex),
       MachineMemOperand::MOStore, MFI.getObjectSize(FrameIndex),
       MFI.getObjectAlign(FrameIndex));
 
   unsigned Opcode = 0;
   if (TRI->isTypeLegalForClass(*RC, MVT::i8)) {
     Opcode = AVR::STDPtrQRr;
   } else if (TRI->isTypeLegalForClass(*RC, MVT::i16)) {
     Opcode = AVR::STDWPtrQRr;
   } else {
     llvm_unreachable("Cannot store this register into a stack slot!");
   }
 
-  BuildMI(MBB, MI, DL, get(Opcode))
+  BuildMI(MBB, MI, DebugLoc(), get(Opcode))
       .addFrameIndex(FrameIndex)
       .addImm(0)
       .addReg(SrcReg, getKillRegState(isKill))
       .addMemOperand(MMO);
 }
 
 void AVRInstrInfo::loadRegFromStackSlot(MachineBasicBlock &MBB,
                                         MachineBasicBlock::iterator MI,
                                         Register DestReg, int FrameIndex,
                                         const TargetRegisterClass *RC,
                                         const TargetRegisterInfo *TRI) const {
-  DebugLoc DL;
-  if (MI != MBB.end()) {
-    DL = MI->getDebugLoc();
-  }
-
   MachineFunction &MF = *MBB.getParent();
   const MachineFrameInfo &MFI = MF.getFrameInfo();
 
   MachineMemOperand *MMO = MF.getMachineMemOperand(
       MachinePointerInfo::getFixedStack(MF, FrameIndex),
       MachineMemOperand::MOLoad, MFI.getObjectSize(FrameIndex),
       MFI.getObjectAlign(FrameIndex));
 
   unsigned Opcode = 0;
   if (TRI->isTypeLegalForClass(*RC, MVT::i8)) {
     Opcode = AVR::LDDRdPtrQ;
   } else if (TRI->isTypeLegalForClass(*RC, MVT::i16)) {
     // Opcode = AVR::LDDWRdPtrQ;
     //: FIXME: remove this once PR13375 gets fixed
     Opcode = AVR::LDDWRdYQ;
   } else {
     llvm_unreachable("Cannot load this register from a stack slot!");
   }
 
-  BuildMI(MBB, MI, DL, get(Opcode), DestReg)
+  BuildMI(MBB, MI, DebugLoc(), get(Opcode), DestReg)
       .addFrameIndex(FrameIndex)
       .addImm(0)
       .addMemOperand(MMO);
 }
 
 const MCInstrDesc &AVRInstrInfo::getBrCond(AVRCC::CondCodes CC) const {
   switch (CC) {
   default: