Apply llvm-prefer-register-over-unsigned from clang-tidy to LLVM

Summary:
This clang-tidy check is looking for unsigned integer variables whose initializer
starts with an implicit cast from llvm::Register and changes the type of the
variable to llvm::Register (dropping the llvm:: where possible).

Partial reverts in:
X86FrameLowering.cpp - Some functions return unsigned and arguably should be MCRegister
X86FixupLEAs.cpp - Some functions return unsigned and arguably should be MCRegister
X86FrameLowering.cpp - Some functions return unsigned and arguably should be MCRegister
HexagonBitSimplify.cpp - Function takes BitTracker::RegisterRef which appears to be unsigned&
MachineVerifier.cpp - Ambiguous operator==() given MCRegister and const Register
PPCFastISel.cpp - No Register::operator-=()
PeepholeOptimizer.cpp - TargetInstrInfo::optimizeLoadInstr() takes an unsigned&
MachineTraceMetrics.cpp - MachineTraceMetrics lacks a suitable constructor

Manual fixups in:
ARMFastISel.cpp - ARMEmitLoad() now takes a Register& instead of unsigned&
HexagonSplitDouble.cpp - Ternary operator was ambiguous between unsigned/Register
HexagonConstExtenders.cpp - Has a local class named Register, used llvm::Register instead of Register.
PPCFastISel.cpp - PPCEmitLoad() now takes a Register& instead of unsigned&

Depends on D65919

Reviewers: arsenm, bogner, craig.topper, RKSimon

Reviewed By: arsenm

Subscribers: RKSimon, craig.topper, lenary, aemerson, wuzish, jholewinski, MatzeB, qcolombet, dschuff, jyknight, dylanmckay, sdardis, nemanjai, jvesely, wdng, nhaehnle, sbc100, jgravelle-google, kristof.beyls, hiraditya, aheejin, kbarton, fedor.sergeev, javed.absar, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, tpr, PkmX, jocewei, jsji, Petar.Avramovic, asbirlea, Jim, s.egerton, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D65962

llvm-svn: 369041
diff --git a/llvm/lib/Target/ARM/A15SDOptimizer.cpp b/llvm/lib/Target/ARM/A15SDOptimizer.cpp
index a4aacfb..30b9c80 100644
--- a/llvm/lib/Target/ARM/A15SDOptimizer.cpp
+++ b/llvm/lib/Target/ARM/A15SDOptimizer.cpp
@@ -133,7 +133,7 @@
                                   const TargetRegisterClass *TRC) {
   if (!MO.isReg())
     return false;
-  unsigned Reg = MO.getReg();
+  Register Reg = MO.getReg();
 
   if (Register::isVirtualRegister(Reg))
     return MRI->getRegClass(Reg)->hasSuperClassEq(TRC);
@@ -191,7 +191,7 @@
     for (MachineOperand &MO : MI->operands()) {
       if ((!MO.isReg()) || (!MO.isUse()))
         continue;
-      unsigned Reg = MO.getReg();
+      Register Reg = MO.getReg();
       if (!Register::isVirtualRegister(Reg))
         continue;
       MachineOperand *Op = MI->findRegisterDefOperand(Reg);
@@ -213,7 +213,7 @@
       for (MachineOperand &MODef : Def->operands()) {
         if ((!MODef.isReg()) || (!MODef.isDef()))
           continue;
-        unsigned DefReg = MODef.getReg();
+        Register DefReg = MODef.getReg();
         if (!Register::isVirtualRegister(DefReg)) {
           IsDead = false;
           break;
@@ -245,8 +245,8 @@
   }
 
   if (MI->isInsertSubreg()) {
-    unsigned DPRReg = MI->getOperand(1).getReg();
-    unsigned SPRReg = MI->getOperand(2).getReg();
+    Register DPRReg = MI->getOperand(1).getReg();
+    Register SPRReg = MI->getOperand(2).getReg();
 
     if (Register::isVirtualRegister(DPRReg) && Register::isVirtualRegister(SPRReg)) {
       MachineInstr *DPRMI = MRI->getVRegDef(MI->getOperand(1).getReg());
@@ -267,7 +267,7 @@
 
             // Find the thing we're subreg copying out of - is it of the same
             // regclass as DPRMI? (i.e. a DPR or QPR).
-            unsigned FullReg = SPRMI->getOperand(1).getReg();
+            Register FullReg = SPRMI->getOperand(1).getReg();
             const TargetRegisterClass *TRC =
               MRI->getRegClass(MI->getOperand(1).getReg());
             if (TRC->hasSuperClassEq(MRI->getRegClass(FullReg))) {
@@ -296,7 +296,7 @@
       if (!MI->getOperand(I).isReg())
         continue;
       ++NumTotal;
-      unsigned OpReg = MI->getOperand(I).getReg();
+      Register OpReg = MI->getOperand(I).getReg();
 
       if (!Register::isVirtualRegister(OpReg))
         break;
@@ -369,7 +369,7 @@
      Reached.insert(MI);
      if (MI->isPHI()) {
        for (unsigned I = 1, E = MI->getNumOperands(); I != E; I += 2) {
-         unsigned Reg = MI->getOperand(I).getReg();
+         Register Reg = MI->getOperand(I).getReg();
          if (!Register::isVirtualRegister(Reg)) {
            continue;
          }
@@ -418,8 +418,8 @@
                                        MachineBasicBlock::iterator InsertBefore,
                                        const DebugLoc &DL, unsigned Reg,
                                        unsigned Lane, bool QPR) {
-  unsigned Out = MRI->createVirtualRegister(QPR ? &ARM::QPRRegClass :
-                                                  &ARM::DPRRegClass);
+  Register Out =
+      MRI->createVirtualRegister(QPR ? &ARM::QPRRegClass : &ARM::DPRRegClass);
   BuildMI(MBB, InsertBefore, DL,
           TII->get(QPR ? ARM::VDUPLN32q : ARM::VDUPLN32d), Out)
       .addReg(Reg)
@@ -434,7 +434,7 @@
     MachineBasicBlock &MBB, MachineBasicBlock::iterator InsertBefore,
     const DebugLoc &DL, unsigned DReg, unsigned Lane,
     const TargetRegisterClass *TRC) {
-  unsigned Out = MRI->createVirtualRegister(TRC);
+  Register Out = MRI->createVirtualRegister(TRC);
   BuildMI(MBB,
           InsertBefore,
           DL,
@@ -448,7 +448,7 @@
 unsigned A15SDOptimizer::createRegSequence(
     MachineBasicBlock &MBB, MachineBasicBlock::iterator InsertBefore,
     const DebugLoc &DL, unsigned Reg1, unsigned Reg2) {
-  unsigned Out = MRI->createVirtualRegister(&ARM::QPRRegClass);
+  Register Out = MRI->createVirtualRegister(&ARM::QPRRegClass);
   BuildMI(MBB,
           InsertBefore,
           DL,
@@ -466,7 +466,7 @@
                                     MachineBasicBlock::iterator InsertBefore,
                                     const DebugLoc &DL, unsigned Ssub0,
                                     unsigned Ssub1) {
-  unsigned Out = MRI->createVirtualRegister(&ARM::DPRRegClass);
+  Register Out = MRI->createVirtualRegister(&ARM::DPRRegClass);
   BuildMI(MBB, InsertBefore, DL, TII->get(ARM::VEXTd32), Out)
       .addReg(Ssub0)
       .addReg(Ssub1)
@@ -478,7 +478,7 @@
 unsigned A15SDOptimizer::createInsertSubreg(
     MachineBasicBlock &MBB, MachineBasicBlock::iterator InsertBefore,
     const DebugLoc &DL, unsigned DReg, unsigned Lane, unsigned ToInsert) {
-  unsigned Out = MRI->createVirtualRegister(&ARM::DPR_VFP2RegClass);
+  Register Out = MRI->createVirtualRegister(&ARM::DPR_VFP2RegClass);
   BuildMI(MBB,
           InsertBefore,
           DL,
@@ -494,7 +494,7 @@
 A15SDOptimizer::createImplicitDef(MachineBasicBlock &MBB,
                                   MachineBasicBlock::iterator InsertBefore,
                                   const DebugLoc &DL) {
-  unsigned Out = MRI->createVirtualRegister(&ARM::DPRRegClass);
+  Register Out = MRI->createVirtualRegister(&ARM::DPRRegClass);
   BuildMI(MBB,
           InsertBefore,
           DL,
@@ -622,7 +622,7 @@
 
       // Collect all the uses of this MI's DPR def for updating later.
       SmallVector<MachineOperand*, 8> Uses;
-      unsigned DPRDefReg = MI->getOperand(0).getReg();
+      Register DPRDefReg = MI->getOperand(0).getReg();
       for (MachineRegisterInfo::use_iterator I = MRI->use_begin(DPRDefReg),
              E = MRI->use_end(); I != E; ++I)
         Uses.push_back(&*I);