[clang] [PAuth] Use different discriminators for __int128_t / __uint128_t / _BitInt(n) (PR #140276)

[Oliver Hunt via cfe-commits]

================
@@ -3383,21 +3383,27 @@ static void encodeTypeForFunctionPointerAuth(const ASTContext &Ctx,
 
   // Don't bother discriminating based on these types.
   case Type::Pipe:
-  case Type::BitInt:
   case Type::ConstantMatrix:
     OS << "?";
     return;
 
+  case Type::BitInt: {
+    const auto *BtTy = T->castAs<BitIntType>();
----------------
ojhunt wrote:

I was a bit (ha!) worried _BitInt was going to be encoded as a generic integer type and was going to ask for 1,8,16,32,64 bit ones to be encoded as regular ints, but mercifully that doesn't appear to be the case \o/

https://github.com/llvm/llvm-project/pull/140276