[lldb] [Process/FreeBSDRemote] Use RegSetKind consistently [NFC]

[mgorny]

Summary

Use RegSetKind enum for register sets everything, rather than int.
Always spell it as 'RegSetKind', without unnecessary 'enum'. Add
missing switch case. While at it, use uint32_t for regnums
consistently.

lldb/source/Plugins/Process/FreeBSDRemote/NativeRegisterContextFreeBSD_x86_64.h

private:
   // Private member variables.
   std::array<uint8_t, sizeof(struct reg)> m_gpr;
   std::array<uint8_t, 512> m_fpr; // FXSAVE
   std::array<uint8_t, sizeof(struct dbreg)> m_dbr;
   std::vector<uint8_t> m_xsave;
   std::array<uint32_t, MaxRegSet + 1> m_xsave_offsets;
   std::array<size_t, MaxRegSet + 1> m_regset_offsets;
 
-  llvm::Optional<enum RegSetKind> GetSetForNativeRegNum(int reg_num) const;
+  llvm::Optional<RegSetKind> GetSetForNativeRegNum(uint32_t reg_num) const;
 
-  Status ReadRegisterSet(uint32_t set);
-  Status WriteRegisterSet(uint32_t set);
+  Status ReadRegisterSet(RegSetKind set);
+  Status WriteRegisterSet(RegSetKind set);
 
-  uint8_t *GetOffsetRegSetData(uint32_t set, size_t reg_offset);
+  uint8_t *GetOffsetRegSetData(RegSetKind set, size_t reg_offset);
 
   struct YMMSplitPtr {
     void *xmm;
     void *ymm_hi;
   };
   llvm::Optional<YMMSplitPtr> GetYMMSplitReg(uint32_t reg);
 };
 
 } // namespace process_freebsd
 } // namespace lldb_private
 
 #endif // #ifndef lldb_NativeRegisterContextFreeBSD_x86_64_h
 
 #endif // defined(__x86_64__)

lldb/source/Plugins/Process/FreeBSDRemote/NativeRegisterContextFreeBSD_x86_64.cpp

case llvm::Triple::x86:
     return &g_reg_sets_i386[set_index];
   case llvm::Triple::x86_64:
     return &g_reg_sets_x86_64[set_index];
   default:
     llvm_unreachable("Unhandled target architecture.");
   }
 }
 
-llvm::Optional<enum NativeRegisterContextFreeBSD_x86_64::RegSetKind>
-NativeRegisterContextFreeBSD_x86_64::GetSetForNativeRegNum(int reg_num) const {
+llvm::Optional<NativeRegisterContextFreeBSD_x86_64::RegSetKind>
+NativeRegisterContextFreeBSD_x86_64::GetSetForNativeRegNum(
+    uint32_t reg_num) const {
   switch (GetRegisterInfoInterface().GetTargetArchitecture().GetMachine()) {
   case llvm::Triple::x86:
     if (reg_num >= k_first_gpr_i386 && reg_num <= k_last_gpr_i386)
       return GPRegSet;
     if (reg_num >= k_first_fpr_i386 && reg_num <= k_last_fpr_i386)
       return FPRegSet;
     if (reg_num >= k_first_avx_i386 && reg_num <= k_last_avx_i386)
       return YMMRegSet;
case llvm::Triple::x86_64:
     break;
   default:
     llvm_unreachable("Unhandled target architecture.");
   }
 
   llvm_unreachable("Register does not belong to any register set");
 }
 
-Status NativeRegisterContextFreeBSD_x86_64::ReadRegisterSet(uint32_t set) {
+Status NativeRegisterContextFreeBSD_x86_64::ReadRegisterSet(RegSetKind set) {
   switch (set) {
   case GPRegSet:
     return NativeProcessFreeBSD::PtraceWrapper(PT_GETREGS, m_thread.GetID(),
                                                m_gpr.data());
   case FPRegSet:
 #if defined(__x86_64__)
     return NativeProcessFreeBSD::PtraceWrapper(PT_GETFPREGS, m_thread.GetID(),
                                                m_fpr.data());
case MPXRegSet: {
     m_xsave.resize(info.xsave_len);
     return NativeProcessFreeBSD::PtraceWrapper(PT_GETXSTATE, GetProcessPid(),
                                                m_xsave.data(), m_xsave.size());
   }
   }
   llvm_unreachable("NativeRegisterContextFreeBSD_x86_64::ReadRegisterSet");
 }
 
-Status NativeRegisterContextFreeBSD_x86_64::WriteRegisterSet(uint32_t set) {
+Status NativeRegisterContextFreeBSD_x86_64::WriteRegisterSet(RegSetKind set) {
   switch (set) {
   case GPRegSet:
     return NativeProcessFreeBSD::PtraceWrapper(PT_SETREGS, m_thread.GetID(),
                                                m_gpr.data());
   case FPRegSet:
 #if defined(__x86_64__)
     return NativeProcessFreeBSD::PtraceWrapper(PT_SETFPREGS, m_thread.GetID(),
                                                m_fpr.data());
if (reg == LLDB_INVALID_REGNUM) {
     // This is likely an internal register for lldb use only and should not be
     // directly queried.
     error.SetErrorStringWithFormat("register \"%s\" is an internal-only lldb "
                                    "register, cannot read directly",
                                    reg_info->name);
     return error;
   }
 
-  llvm::Optional<enum RegSetKind> opt_set = GetSetForNativeRegNum(reg);
+  llvm::Optional<RegSetKind> opt_set = GetSetForNativeRegNum(reg);
   if (!opt_set) {
     // This is likely an internal register for lldb use only and should not be
     // directly queried.
     error.SetErrorStringWithFormat("register \"%s\" is in unrecognized set",
                                    reg_info->name);
     return error;
   }
 
-  enum RegSetKind set = opt_set.getValue();
+  RegSetKind set = opt_set.getValue();
   error = ReadRegisterSet(set);
   if (error.Fail())
     return error;
 
   switch (set) {
   case GPRegSet:
   case FPRegSet:
   case DBRegSet: {
if (reg == LLDB_INVALID_REGNUM) {
     // This is likely an internal register for lldb use only and should not be
     // directly queried.
     error.SetErrorStringWithFormat("register \"%s\" is an internal-only lldb "
                                    "register, cannot read directly",
                                    reg_info->name);
     return error;
   }
 
-  llvm::Optional<enum RegSetKind> opt_set = GetSetForNativeRegNum(reg);
+  llvm::Optional<RegSetKind> opt_set = GetSetForNativeRegNum(reg);
   if (!opt_set) {
     // This is likely an internal register for lldb use only and should not be
     // directly queried.
     error.SetErrorStringWithFormat("register \"%s\" is in unrecognized set",
                                    reg_info->name);
     return error;
   }
 
-  enum RegSetKind set = opt_set.getValue();
+  RegSetKind set = opt_set.getValue();
   error = ReadRegisterSet(set);
   if (error.Fail())
     return error;
 
   switch (set) {
   case GPRegSet:
   case FPRegSet:
   case DBRegSet: {
if (!res.Fail()) {
 
     m_dbr = r_source.m_dbr;
     res = WriteRegisterSet(DBRegSet);
   }
   return res.ToError();
 }
 
 uint8_t *
-NativeRegisterContextFreeBSD_x86_64::GetOffsetRegSetData(uint32_t set,
+NativeRegisterContextFreeBSD_x86_64::GetOffsetRegSetData(RegSetKind set,
                                                          size_t reg_offset) {
   uint8_t *base;
   switch (set) {
   case GPRegSet:
     base = m_gpr.data();
     break;
   case FPRegSet:
     base = m_fpr.data();
     break;
   case DBRegSet:
     base = m_dbr.data();
     break;
   case YMMRegSet:
     llvm_unreachable("GetRegSetData() is unsuitable for this regset.");
+  case MPXRegSet:
+    llvm_unreachable("MPX regset should have returned error");
   }
   assert(reg_offset >= m_regset_offsets[set]);
   return base + (reg_offset - m_regset_offsets[set]);
 }
 
 llvm::Optional<NativeRegisterContextFreeBSD_x86_64::YMMSplitPtr>
 NativeRegisterContextFreeBSD_x86_64::GetYMMSplitReg(uint32_t reg) {
   uint32_t offset = m_xsave_offsets[YMMRegSet];