Add PLATFORM driverkit

[tschuett]

Summary

Add the PLATFORM_DRIVERKIT entry to the PlatformType enum in MachO.h

I have no commit access.

[compnerd]

I had this part of the change already :) This isn't the interesting part. This is missing the test cases and the remainder of the support needed to add driver kit. Just the enumerated value is of little value since none of the tooling really understands the value.

llvm/include/llvm/BinaryFormat/MachO.h

enum PlatformType {
   PLATFORM_MACOS = 1,
   PLATFORM_IOS = 2,
   PLATFORM_TVOS = 3,
   PLATFORM_WATCHOS = 4,
   PLATFORM_BRIDGEOS = 5,
   PLATFORM_MACCATALYST = 6,
   PLATFORM_IOSSIMULATOR = 7,
   PLATFORM_TVOSSIMULATOR = 8,
-  PLATFORM_WATCHOSSIMULATOR = 9
+  PLATFORM_WATCHOSSIMULATOR = 9,
+  PLATFORM_DRIVERKIT = 10
 };
 
 // Values for tools enum in build_tool_version.
 enum { TOOL_CLANG = 1, TOOL_SWIFT = 2, TOOL_LD = 3 };
 
 // Structs from <mach-o/loader.h>
 
 struct mach_header {

llvm/include/llvm/Object/MachO.h

static std::string getBuildPlatform(uint32_t platform) {
     case MachO::PLATFORM_IOS: return "ios";
     case MachO::PLATFORM_TVOS: return "tvos";
     case MachO::PLATFORM_WATCHOS: return "watchos";
     case MachO::PLATFORM_BRIDGEOS: return "bridgeos";
     case MachO::PLATFORM_MACCATALYST: return "macCatalyst";
     case MachO::PLATFORM_IOSSIMULATOR: return "iossimulator";
     case MachO::PLATFORM_TVOSSIMULATOR: return "tvossimulator";
     case MachO::PLATFORM_WATCHOSSIMULATOR: return "watchossimulator";
+    case MachO::PLATFORM_DRIVERKIT: return "driverkit";
     default:
       std::string ret;
       raw_string_ostream ss(ret);
       ss << format_hex(platform, 8, true);
       return ss.str();
     }
   }
 

llvm/lib/MC/MCAsmStreamer.cpp

static const char *getPlatformName(MachO::PlatformType Type) {
   case MachO::PLATFORM_IOS:              return "ios";
   case MachO::PLATFORM_TVOS:             return "tvos";
   case MachO::PLATFORM_WATCHOS:          return "watchos";
   case MachO::PLATFORM_BRIDGEOS:         return "bridgeos";
   case MachO::PLATFORM_MACCATALYST:      return "macCatalyst";
   case MachO::PLATFORM_IOSSIMULATOR:     return "iossimulator";
   case MachO::PLATFORM_TVOSSIMULATOR:    return "tvossimulator";
   case MachO::PLATFORM_WATCHOSSIMULATOR: return "watchossimulator";
+  case MachO::PLATFORM_DRIVERKIT:        return "driverkit";
   }
   llvm_unreachable("Invalid Mach-O platform type");
 }
 
 void MCAsmStreamer::emitBuildVersion(unsigned Platform, unsigned Major,
                                      unsigned Minor, unsigned Update,
                                      VersionTuple SDKVersion) {
   const char *PlatformName = getPlatformName((MachO::PlatformType)Platform);

llvm/lib/MC/MCParser/DarwinAsmParser.cpp

static Triple::OSType getOSTypeFromPlatform(MachO::PlatformType Type) {
   case MachO::PLATFORM_IOS:     return Triple::IOS;
   case MachO::PLATFORM_TVOS:    return Triple::TvOS;
   case MachO::PLATFORM_WATCHOS: return Triple::WatchOS;
   case MachO::PLATFORM_BRIDGEOS:         /* silence warning */ break;
   case MachO::PLATFORM_MACCATALYST: return Triple::IOS;
   case MachO::PLATFORM_IOSSIMULATOR:     /* silence warning */ break;
   case MachO::PLATFORM_TVOSSIMULATOR:    /* silence warning */ break;
   case MachO::PLATFORM_WATCHOSSIMULATOR: /* silence warning */ break;
+  case MachO::PLATFORM_DRIVERKIT:        /* silence warning */ break;
   }
   llvm_unreachable("Invalid mach-o platform type");
 }
 
 /// parseBuildVersion
 ///   ::= .build_version (macos|ios|tvos|watchos), parseVersion parseSDKVersion
 bool DarwinAsmParser::parseBuildVersion(StringRef Directive, SMLoc Loc) {
   StringRef PlatformName;