Revert rG57ee0435bd47f23f3939f402914c231b4f65ca5e - [TII] Use optiona…

…l destination and source pair as a return value; NFC

This is breaking MSVC builds: http://lab.llvm.org:8011/builders/llvm-clang-x86_64-expensive-checks-win/builds/20375

llvm/include/llvm/CodeGen/TargetInstrInfo.h

@@ -64,11 +64,6 @@ template <class T> class SmallVectorImpl;
 
 using ParamLoadedValue = std::pair<MachineOperand, DIExpression*>;
 
-struct DestSourcePair {
-  const MachineOperand &Destination;
-  const MachineOperand &Source;
-};
-
 //---------------------------------------------------------------------------
 ///
 /// TargetInstrInfo - Interface to description of machine instruction set
@@ -923,36 +918,41 @@ class TargetInstrInfo : public MCInstrInfo {
   }
 
 protected:
-  /// Target-dependent implementation for IsCopyInstr.
+  /// Target-dependent implemenation for IsCopyInstr.
   /// If the specific machine instruction is a instruction that moves/copies
-  /// value from one register to another register return destination and source
-  /// registers as machine operands.
-  virtual Optional<DestSourcePair>
-  isCopyInstrImpl(const MachineInstr &MI) const {
-    return None;
+  /// value from one register to another register return true along with
+  /// @Source machine operand and @Destination machine operand.
+  virtual bool isCopyInstrImpl(const MachineInstr &MI,
+                               const MachineOperand *&Source,
+                               const MachineOperand *&Destination) const {
+    return false;
   }
 
 public:
   /// If the specific machine instruction is a instruction that moves/copies
-  /// value from one register to another register return destination and source
-  /// registers as machine operands.
-  /// For COPY-instruction the method naturally returns destination and source
-  /// registers as machine operands, for all other instructions the method calls
-  /// target-dependent implementation.
-  Optional<DestSourcePair> isCopyInstr(const MachineInstr &MI) const {
+  /// value from one register to another register return true along with
+  /// @Source machine operand and @Destination machine operand.
+  /// For COPY-instruction the method naturally returns true, for all other
+  /// instructions the method calls target-dependent implementation.
+  bool isCopyInstr(const MachineInstr &MI, const MachineOperand *&Source,
+                   const MachineOperand *&Destination) const {
     if (MI.isCopy()) {
-      return DestSourcePair{MI.getOperand(0), MI.getOperand(1)};
+      Destination = &MI.getOperand(0);
+      Source = &MI.getOperand(1);
+      return true;
     }
-    return isCopyInstrImpl(MI);
+    return isCopyInstrImpl(MI, Source, Destination);
   }
 
   /// If the specific machine instruction is an instruction that adds an
-  /// immediate value to its source operand and stores it in destination,
-  /// return destination and source registers as machine operands along with
-  /// \c Offset which has been added.
-  virtual Optional<DestSourcePair> isAddImmediate(const MachineInstr &MI,
-                                                  int64_t &Offset) const {
-    return None;
+  /// immediate value to its \c Source operand and stores it in \c Destination,
+  /// return true along with \c Destination and \c Source machine operand to
+  /// which \c Offset has been added.
+  virtual bool isAddImmediate(const MachineInstr &MI,
+                              const MachineOperand *&Destination,
+                              const MachineOperand *&Source,
+                              int64_t &Offset) const {
+    return false;
   }
 
   /// Store the specified register of the given register class to the specified

llvm/lib/CodeGen/LiveDebugValues.cpp

@@ -997,14 +997,10 @@ void LiveDebugValues::transferRegisterCopy(MachineInstr &MI,
                                            OpenRangesSet &OpenRanges,
                                            VarLocMap &VarLocIDs,
                                            TransferMap &Transfers) {
+  const MachineOperand *SrcRegOp, *DestRegOp;
 
-  auto DestSrc = TII->isCopyInstr(MI);
-  if (!DestSrc)
-    return;
-
-  const MachineOperand &DestRegOp = DestSrc->Destination;
-  const MachineOperand &SrcRegOp = DestSrc->Source;
-  if (!SrcRegOp.isKill() || !DestRegOp.isDef())
+  if (!TII->isCopyInstr(MI, SrcRegOp, DestRegOp) || !SrcRegOp->isKill() ||
+      !DestRegOp->isDef())
     return;
 
   auto isCalleeSavedReg = [&](unsigned Reg) {
@@ -1014,8 +1010,8 @@ void LiveDebugValues::transferRegisterCopy(MachineInstr &MI,
     return false;
   };
 
-  Register SrcReg = SrcRegOp.getReg();
-  Register DestReg = DestRegOp.getReg();
+  Register SrcReg = SrcRegOp->getReg();
+  Register DestReg = DestRegOp->getReg();
 
   // We want to recognize instructions where destination register is callee
   // saved register. If register that could be clobbered by the call is

llvm/lib/CodeGen/TargetInstrInfo.cpp

@@ -1124,13 +1124,14 @@ Optional<ParamLoadedValue>
 TargetInstrInfo::describeLoadedValue(const MachineInstr &MI) const {
   const MachineFunction *MF = MI.getMF();
   DIExpression *Expr = DIExpression::get(MF->getFunction().getContext(), {});
+  const MachineOperand *SrcRegOp, *DestRegOp;
   int64_t Offset;
 
-  if (auto DestSrc = isCopyInstr(MI)) {
-    return ParamLoadedValue(DestSrc->Source, Expr);
-  } else if (auto DestSrc = isAddImmediate(MI, Offset)) {
+  if (isCopyInstr(MI, SrcRegOp, DestRegOp)) {
+    return ParamLoadedValue(*SrcRegOp, Expr);
+  } else if (isAddImmediate(MI, DestRegOp, SrcRegOp, Offset)) {
     Expr = DIExpression::prepend(Expr, DIExpression::ApplyOffset, Offset);
-    return ParamLoadedValue(DestSrc->Source, Expr);
+    return ParamLoadedValue(*SrcRegOp, Expr);
   }
 
   return None;

llvm/lib/Target/AArch64/AArch64InstrInfo.cpp

@@ -5936,33 +5936,39 @@ bool AArch64InstrInfo::shouldOutlineFromFunctionByDefault(
   return MF.getFunction().hasMinSize();
 }
 
-Optional<DestSourcePair>
-AArch64InstrInfo::isCopyInstrImpl(const MachineInstr &MI) const {
+bool AArch64InstrInfo::isCopyInstrImpl(
+    const MachineInstr &MI, const MachineOperand *&Source,
+    const MachineOperand *&Destination) const {
 
   // AArch64::ORRWrs and AArch64::ORRXrs with WZR/XZR reg
   // and zero immediate operands used as an alias for mov instruction.
   if (MI.getOpcode() == AArch64::ORRWrs &&
       MI.getOperand(1).getReg() == AArch64::WZR &&
       MI.getOperand(3).getImm() == 0x0) {
-    return DestSourcePair{MI.getOperand(0), MI.getOperand(2)};
+    Destination = &MI.getOperand(0);
+    Source = &MI.getOperand(2);
+    return true;
   }
 
   if (MI.getOpcode() == AArch64::ORRXrs &&
       MI.getOperand(1).getReg() == AArch64::XZR &&
       MI.getOperand(3).getImm() == 0x0) {
-    return DestSourcePair{MI.getOperand(0), MI.getOperand(2)};
+    Destination = &MI.getOperand(0);
+    Source = &MI.getOperand(2);
+    return true;
   }
 
-  return None;
+  return false;
 }
 
-Optional<DestSourcePair>
-AArch64InstrInfo::isAddImmediate(const MachineInstr &MI,
-                                 int64_t &Offset) const {
+bool AArch64InstrInfo::isAddImmediate(const MachineInstr &MI,
+                                      const MachineOperand *&Destination,
+                                      const MachineOperand *&Source,
+                                      int64_t &Offset) const {
   int Sign = 1;
   switch (MI.getOpcode()) {
   default:
-    return None;
+    return false;
   case AArch64::SUBWri:
   case AArch64::SUBXri:
   case AArch64::SUBSWri:
@@ -5976,14 +5982,16 @@ AArch64InstrInfo::isAddImmediate(const MachineInstr &MI,
     // TODO: Third operand can be global address (usually some string).
     if (!MI.getOperand(0).isReg() || !MI.getOperand(1).isReg() ||
         !MI.getOperand(2).isImm())
-      return None;
+      return false;
+    Source = &MI.getOperand(1);
     Offset = MI.getOperand(2).getImm() * Sign;
     int Shift = MI.getOperand(3).getImm();
     assert((Shift == 0 || Shift == 12) && "Shift can be either 0 or 12");
     Offset = Offset << Shift;
   }
   }
-  return DestSourcePair{MI.getOperand(0), MI.getOperand(1)};
+  Destination = &MI.getOperand(0);
+  return true;
 }
 
 Optional<ParamLoadedValue>

llvm/lib/Target/AArch64/AArch64InstrInfo.h

@@ -265,8 +265,10 @@ class AArch64InstrInfo final : public AArch64GenInstrInfo {
   /// on Windows.
   static bool isSEHInstruction(const MachineInstr &MI);
 
-  Optional<DestSourcePair> isAddImmediate(const MachineInstr &MI,
-                                          int64_t &Offset) const override;
+  bool isAddImmediate(const MachineInstr &MI,
+                      const MachineOperand *&Destination,
+                      const MachineOperand *&Source,
+                      int64_t &Offset) const override;
 
   Optional<ParamLoadedValue>
   describeLoadedValue(const MachineInstr &MI) const override;
@@ -275,11 +277,11 @@ class AArch64InstrInfo final : public AArch64GenInstrInfo {
 #include "AArch64GenInstrInfo.inc"
 
 protected:
-  /// If the specific machine instruction is an instruction that moves/copies
-  /// value from one register to another register return destination and source
-  /// registers as machine operands.
-  Optional<DestSourcePair>
-  isCopyInstrImpl(const MachineInstr &MI) const override;
+  /// If the specific machine instruction is a instruction that moves/copies
+  /// value from one register to another register return true along with
+  /// @Source machine operand and @Destination machine operand.
+  bool isCopyInstrImpl(const MachineInstr &MI, const MachineOperand *&Source,
+                       const MachineOperand *&Destination) const override;
 
 private:
   /// Sets the offsets on outlined instructions in \p MBB which use SP

llvm/lib/Target/ARM/ARMBaseInstrInfo.cpp

@@ -993,8 +993,9 @@ void ARMBaseInstrInfo::copyPhysReg(MachineBasicBlock &MBB,
     Mov->addRegisterKilled(SrcReg, TRI);
 }
 
-Optional<DestSourcePair>
-ARMBaseInstrInfo::isCopyInstrImpl(const MachineInstr &MI) const {
+bool ARMBaseInstrInfo::isCopyInstrImpl(const MachineInstr &MI,
+                                       const MachineOperand *&Src,
+                                       const MachineOperand *&Dest) const {
   // VMOVRRD is also a copy instruction but it requires
   // special way of handling. It is more complex copy version
   // and since that we are not considering it. For recognition
@@ -1005,8 +1006,10 @@ ARMBaseInstrInfo::isCopyInstrImpl(const MachineInstr &MI) const {
   if (!MI.isMoveReg() ||
       (MI.getOpcode() == ARM::VORRq &&
        MI.getOperand(1).getReg() != MI.getOperand(2).getReg()))
-    return None;
-  return DestSourcePair{MI.getOperand(0), MI.getOperand(1)};
+    return false;
+  Dest = &MI.getOperand(0);
+  Src = &MI.getOperand(1);
+  return true;
 }
 
 const MachineInstrBuilder &
@@ -5347,27 +5350,30 @@ ARMBaseInstrInfo::getSerializableBitmaskMachineOperandTargetFlags() const {
   return makeArrayRef(TargetFlags);
 }
 
-Optional<DestSourcePair>
-ARMBaseInstrInfo::isAddImmediate(const MachineInstr &MI,
-                                 int64_t &Offset) const {
+bool ARMBaseInstrInfo::isAddImmediate(const MachineInstr &MI,
+                                      const MachineOperand *&Destination,
+                                      const MachineOperand *&Source,
+                                      int64_t &Offset) const {
   int Sign = 1;
   unsigned Opcode = MI.getOpcode();
 
   // We describe SUBri or ADDri instructions.
   if (Opcode == ARM::SUBri)
     Sign = -1;
   else if (Opcode != ARM::ADDri)
-    return None;
+    return false;
 
   // TODO: Third operand can be global address (usually some string). Since
   //       strings can be relocated we cannot calculate their offsets for
   //       now.
   if (!MI.getOperand(0).isReg() || !MI.getOperand(1).isReg() ||
       !MI.getOperand(2).isImm())
-    return None;
+    return false;
 
+  Destination = &MI.getOperand(0);
+  Source = &MI.getOperand(1);
   Offset = MI.getOperand(2).getImm() * Sign;
-  return DestSourcePair{MI.getOperand(0), MI.getOperand(1)};
+  return true;
 }
 
 bool llvm::registerDefinedBetween(unsigned Reg,

llvm/lib/Target/ARM/ARMBaseInstrInfo.h

@@ -99,11 +99,12 @@ class ARMBaseInstrInfo : public ARMGenInstrInfo {
   MachineInstr *commuteInstructionImpl(MachineInstr &MI, bool NewMI,
                                        unsigned OpIdx1,
                                        unsigned OpIdx2) const override;
-  /// If the specific machine instruction is an instruction that moves/copies
-  /// value from one register to another register return destination and source
-  /// registers as machine operands.
-  Optional<DestSourcePair>
-  isCopyInstrImpl(const MachineInstr &MI) const override;
+
+  /// If the specific machine instruction is a instruction that moves/copies
+  /// value from one register to another register return true along with
+  /// @Source machine operand and @Destination machine operand.
+  bool isCopyInstrImpl(const MachineInstr &MI, const MachineOperand *&Source,
+                       const MachineOperand *&Destination) const override;
 
 public:
   // Return whether the target has an explicit NOP encoding.
@@ -455,8 +456,10 @@ class ARMBaseInstrInfo : public ARMGenInstrInfo {
     return MI.getOperand(3).getReg();
   }
 
-  Optional<DestSourcePair> isAddImmediate(const MachineInstr &MI,
-                                          int64_t &Offset) const override;
+  bool isAddImmediate(const MachineInstr &MI,
+                      const MachineOperand *&Destination,
+                      const MachineOperand *&Source,
+                      int64_t &Offset) const override;
 };
 
 /// Get the operands corresponding to the given \p Pred value. By default, the

llvm/lib/Target/Mips/Mips16InstrInfo.cpp

@@ -96,11 +96,15 @@ void Mips16InstrInfo::copyPhysReg(MachineBasicBlock &MBB,
     MIB.addReg(SrcReg, getKillRegState(KillSrc));
 }
 
-Optional<DestSourcePair>
-Mips16InstrInfo::isCopyInstrImpl(const MachineInstr &MI) const {
-  if (MI.isMoveReg())
-    return DestSourcePair{MI.getOperand(0), MI.getOperand(1)};
-  return None;
+bool Mips16InstrInfo::isCopyInstrImpl(const MachineInstr &MI,
+                                      const MachineOperand *&Src,
+                                      const MachineOperand *&Dest) const {
+  if (MI.isMoveReg()) {
+    Dest = &MI.getOperand(0);
+    Src = &MI.getOperand(1);
+    return true;
+  }
+  return false;
 }
 
 void Mips16InstrInfo::storeRegToStack(MachineBasicBlock &MBB,

llvm/lib/Target/Mips/Mips16InstrInfo.h

@@ -104,9 +104,10 @@ class Mips16InstrInfo : public MipsInstrInfo {
 
 protected:
   /// If the specific machine instruction is a instruction that moves/copies
-  /// value from one register to another register return destination and source
-  /// registers as machine operands.
-  Optional<DestSourcePair> isCopyInstrImpl(const MachineInstr &MI) const override;
+  /// value from one register to another register return true along with
+  /// @Source machine operand and @Destination machine operand.
+  bool isCopyInstrImpl(const MachineInstr &MI, const MachineOperand *&Source,
+                       const MachineOperand *&Destination) const override;
 
 private:
   unsigned getAnalyzableBrOpc(unsigned Opc) const override;

llvm/lib/Target/Mips/MipsSEInstrInfo.cpp

@@ -221,24 +221,29 @@ static bool isReadOrWriteToDSPReg(const MachineInstr &MI, bool &isWrite) {
 /// We check for the common case of 'or', as it's MIPS' preferred instruction
 /// for GPRs but we have to check the operands to ensure that is the case.
 /// Other move instructions for MIPS are directly identifiable.
-Optional<DestSourcePair>
-MipsSEInstrInfo::isCopyInstrImpl(const MachineInstr &MI) const {
+bool MipsSEInstrInfo::isCopyInstrImpl(const MachineInstr &MI,
+                                      const MachineOperand *&Src,
+                                      const MachineOperand *&Dest) const {
   bool isDSPControlWrite = false;
   // Condition is made to match the creation of WRDSP/RDDSP copy instruction
   // from copyPhysReg function.
   if (isReadOrWriteToDSPReg(MI, isDSPControlWrite)) {
-    if (!MI.getOperand(1).isImm() || MI.getOperand(1).getImm() != (1 << 4))
-      return None;
+    if (!MI.getOperand(1).isImm() || MI.getOperand(1).getImm() != (1<<4))
+      return false;
     else if (isDSPControlWrite) {
-      return DestSourcePair{MI.getOperand(2), MI.getOperand(0)};
-
+      Src = &MI.getOperand(0);
+      Dest = &MI.getOperand(2);
     } else {
-      return DestSourcePair{MI.getOperand(0), MI.getOperand(2)};
+      Dest = &MI.getOperand(0);
+      Src = &MI.getOperand(2);
     }
+    return true;
   } else if (MI.isMoveReg() || isORCopyInst(MI)) {
-    return DestSourcePair{MI.getOperand(0), MI.getOperand(1)};
+    Dest = &MI.getOperand(0);
+    Src = &MI.getOperand(1);
+    return true;
   }
-  return None;
+  return false;
 }
 
 void MipsSEInstrInfo::