Add PLATFORM constants for iOS, tvOS, and watchOS simulators

[mtrent]

Summary

Add PLATFORM constants for iOS, tvOS, and watchOS simulators, as well
as human readable names for these constants, to the Mach-O file format
header files.

rdar://46854119

[davide]

lgtm

[ab]

Looks good, thanks!

llvm/trunk/include/llvm/BinaryFormat/MachO.h

 enum { VM_PROT_READ = 0x1, VM_PROT_WRITE = 0x2, VM_PROT_EXECUTE = 0x4 };
 
 // Values for platform field in build_version_command.
 enum PlatformType {
   PLATFORM_MACOS = 1,
   PLATFORM_IOS = 2,
   PLATFORM_TVOS = 3,
   PLATFORM_WATCHOS = 4,
-  PLATFORM_BRIDGEOS = 5
+  PLATFORM_BRIDGEOS = 5,
+  PLATFORM_IOSSIMULATOR = 7,
+  PLATFORM_TVOSSIMULATOR = 8,
+  PLATFORM_WATCHOSSIMULATOR = 9
 };
 
 // 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/trunk/include/llvm/Object/MachO.h

public:
 
   static std::string getBuildPlatform(uint32_t platform) {
     switch (platform) {
     case MachO::PLATFORM_MACOS: return "macos";
     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_IOSSIMULATOR: return "iossimulator";
+    case MachO::PLATFORM_TVOSSIMULATOR: return "tvossimulator";
+    case MachO::PLATFORM_WATCHOSSIMULATOR: return "watchossimulator";
     default:
       std::string ret;
       raw_string_ostream ss(ret);
       ss << format_hex(platform, 8, true);
       return ss.str();
     }
   }
 

llvm/trunk/lib/MC/MCAsmStreamer.cpp

void MCAsmStreamer::EmitVersionMin(MCVersionMinType Type, unsigned Major,
   if (Update)
     OS << ", " << Update;
   EmitSDKVersionSuffix(OS, SDKVersion);
   EmitEOL();
 }
 
 static const char *getPlatformName(MachO::PlatformType Type) {
   switch (Type) {
-  case MachO::PLATFORM_MACOS:    return "macos";
-  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_MACOS:            return "macos";
+  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_IOSSIMULATOR:     return "iossimulator";
+  case MachO::PLATFORM_TVOSSIMULATOR:    return "tvossimulator";
+  case MachO::PLATFORM_WATCHOSSIMULATOR: return "watchossimulator";
   }
   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/trunk/lib/MC/MCParser/DarwinAsmParser.cpp

 }
 
 static Triple::OSType getOSTypeFromPlatform(MachO::PlatformType Type) {
   switch (Type) {
   case MachO::PLATFORM_MACOS:   return Triple::MacOSX;
   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_BRIDGEOS:         /* silence warning */ break;
+  case MachO::PLATFORM_IOSSIMULATOR:     /* silence warning */ break;
+  case MachO::PLATFORM_TVOSSIMULATOR:    /* silence warning */ break;
+  case MachO::PLATFORM_WATCHOSSIMULATOR: /* 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;