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/AMDGPU/R600InstrInfo.cpp b/llvm/lib/Target/AMDGPU/R600InstrInfo.cpp
index 79e36b7..04a5e93 100644
--- a/llvm/lib/Target/AMDGPU/R600InstrInfo.cpp
+++ b/llvm/lib/Target/AMDGPU/R600InstrInfo.cpp
@@ -293,7 +293,7 @@
     for (unsigned j = 0; j < 8; j++) {
       MachineOperand &MO =
           MI.getOperand(getOperandIdx(MI.getOpcode(), OpTable[j][0]));
-      unsigned Reg = MO.getReg();
+      Register Reg = MO.getReg();
       if (Reg == R600::ALU_CONST) {
         MachineOperand &Sel =
             MI.getOperand(getOperandIdx(MI.getOpcode(), OpTable[j][1]));
@@ -316,7 +316,7 @@
     if (SrcIdx < 0)
       break;
     MachineOperand &MO = MI.getOperand(SrcIdx);
-    unsigned Reg = MO.getReg();
+    Register Reg = MO.getReg();
     if (Reg == R600::ALU_CONST) {
       MachineOperand &Sel =
           MI.getOperand(getOperandIdx(MI.getOpcode(), OpTable[j][1]));
@@ -347,7 +347,7 @@
   unsigned i = 0;
   for (const auto &Src : getSrcs(MI)) {
     ++i;
-    unsigned Reg = Src.first->getReg();
+    Register Reg = Src.first->getReg();
     int Index = RI.getEncodingValue(Reg) & 0xff;
     if (Reg == R600::OQAP) {
       Result.push_back(std::make_pair(Index, 0U));
@@ -864,7 +864,7 @@
   if (idx < 0)
     return false;
 
-  unsigned Reg = MI.getOperand(idx).getReg();
+  Register Reg = MI.getOperand(idx).getReg();
   switch (Reg) {
   default: return false;
   case R600::PRED_SEL_ONE:
@@ -1037,7 +1037,7 @@
       unsigned RegIndex = MI.getOperand(RegOpIdx).getImm();
       unsigned Channel = MI.getOperand(ChanOpIdx).getImm();
       unsigned Address = calculateIndirectAddress(RegIndex, Channel);
-      unsigned OffsetReg = MI.getOperand(OffsetOpIdx).getReg();
+      Register OffsetReg = MI.getOperand(OffsetOpIdx).getReg();
       if (OffsetReg == R600::INDIRECT_BASE_ADDR) {
         buildMovInstr(MBB, MI, MI.getOperand(DstOpIdx).getReg(),
                       getIndirectAddrRegClass()->getRegister(Address));
@@ -1051,7 +1051,7 @@
       unsigned RegIndex = MI.getOperand(RegOpIdx).getImm();
       unsigned Channel = MI.getOperand(ChanOpIdx).getImm();
       unsigned Address = calculateIndirectAddress(RegIndex, Channel);
-      unsigned OffsetReg = MI.getOperand(OffsetOpIdx).getReg();
+      Register OffsetReg = MI.getOperand(OffsetOpIdx).getReg();
       if (OffsetReg == R600::INDIRECT_BASE_ADDR) {
         buildMovInstr(MBB, MI, getIndirectAddrRegClass()->getRegister(Address),
                       MI.getOperand(ValOpIdx).getReg());