[clang] [StrTable] Mechanically convert NVPTX builtins to use TableGen (PR #122873)

[Artem Belevich via cfe-commits]

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@@ -104,9 +104,39 @@ class PrototypeParser {
 
   void ParseType(StringRef T) {
     T = T.trim();
+
+    auto ConsumeAddrSpace = [&]() -> std::optional<unsigned> {
+      T = T.trim();
+      if (!T.consume_back(">"))
+        return std::nullopt;
+
+      auto Open = T.find_last_of('<');
+      if (Open == StringRef::npos)
+        PrintFatalError(Loc, "Mismatched angle-brackets in type");
+
+      StringRef ArgStr = T.substr(Open + 1);
+      T = T.slice(0, Open);
+      if (!T.consume_back("address_space"))
+        PrintFatalError(Loc,
+                        "Only `address_space<N>` supported as a parameterized "
+                        "pointer or reference type qualifier");
+
+      unsigned Number = 0;
+      if (ArgStr.getAsInteger(10, Number))
+        PrintFatalError(
+            Loc, "Expected an integer argument to the address_space qualifier");
+      if (Number == 0)
+        PrintFatalError(Loc, "No need for a qualifier for address space `0`");
+      return Number;
+    };
+
     if (T.consume_back("*")) {
+      // Pointers may have an address space qualifier immediately before them.
+      std::optional<unsigned> AS = ConsumeAddrSpace();
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Artem-B wrote:

Do we have any tests for the tablegen parser changes?

https://github.com/llvm/llvm-project/pull/122873