[clang] Mechanically port bulk of x86 builtins to TableGen (PR #120831)

[Craig Topper via cfe-commits]

================
@@ -108,9 +109,15 @@ class PrototypeParser {
     } else if (T.consume_back("&")) {
       ParseType(T);
       Type += "&";
+    } else if (T.consume_front("long long")) {
----------------
topperc wrote:

It feels a bit surprising that "long long" wouldn't map to "LL". I get that we need to support OpenCL, but maybe we should have a keyword for OpenCL? Are all targets going to want "O" for "long long"?

https://github.com/llvm/llvm-project/pull/120831