[llvm-ifs] Fixing hardcoding of PlatformKind for TBD generation

[plotfi]

Summary

@cishida noticed I had hardcoded PlatformKind in my TBD generation in my first commit of llvm-ifs. This is a differential to get that rectified.

Any pointers on what the proper triple for BridgeOS should be would be helpful.

[cishida]

bridgeOS hasn't been added to llvm triple yet, so it's fine to exclude it for now.
also I have a patch I'm adding very soon that takes in llvm::triple and does the arch/platform mapping so you won't need to. I'll update this file when it comes out.

[cishida]

LGTM

[plotfi]

In D67255#1660946, @cishida wrote:

bridgeOS hasn't been added to llvm triple yet, so it's fine to exclude it for now.
also I have a patch I'm adding very soon that takes in llvm::triple and does the arch/platform mapping so you won't need to. I'll update this file when it comes out.

Awesome. Thanks @cishida 🙏

llvm/tools/llvm-ifs/llvm-ifs.cpp

     }
   }(T);
 
+  auto PlatformKindOrError =
+      [](const llvm::Triple &T) -> llvm::Expected<llvm::MachO::PlatformKind> {
+    if (T.isiOS())
+      return llvm::MachO::PlatformKind::iOS;
+    if (T.isMacOSX())
+      return llvm::MachO::PlatformKind::macOS;
+    if (T.isTvOS())
+      return llvm::MachO::PlatformKind::tvOS;
+    if (T.isWatchOS())
+      return llvm::MachO::PlatformKind::watchOS;
+    return createStringError(errc::not_supported, "Invalid Platform.");
+  }(T);
+
   if (!ArchOrError)
     return -1;
 
+  if (!PlatformKindOrError)
+    return -1;
+
   Architecture Arch = ArchOrError.get();
+  PlatformKind Plat = PlatformKindOrError.get();
 
   InterfaceFile File;
   File.setFileType(FileType::TBD_V3);
   File.setArchitectures(Arch);
-  File.setPlatform(PlatformKind::macOS);
+  File.setPlatform(Plat);
 
   for (const auto &Symbol : Symbols) {
     auto Name = Symbol.Name;