[clang] [CIR] Upstream initial attribute support (PR #121069)

[Erich Keane via cfe-commits]

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@@ -21,18 +39,160 @@ using namespace cir;
 
 Attribute CIRDialect::parseAttribute(DialectAsmParser &parser,
                                      Type type) const {
-  // No attributes yet to parse
-  return Attribute{};
+  llvm::SMLoc typeLoc = parser.getCurrentLocation();
+  llvm::StringRef mnemonic;
+  Attribute genAttr;
+  OptionalParseResult parseResult =
+      generatedAttributeParser(parser, &mnemonic, type, genAttr);
+  if (parseResult.has_value())
+    return genAttr;
+  parser.emitError(typeLoc, "unknown attribute in CIR dialect");
+  return Attribute();
 }
 
 void CIRDialect::printAttribute(Attribute attr, DialectAsmPrinter &os) const {
-  // No attributes yet to print
+  if (failed(generatedAttributePrinter(attr, os)))
+    llvm_unreachable("unexpected CIR type kind");
+}
+
+//===----------------------------------------------------------------------===//
+// ConstPtrAttr definitions
+//===----------------------------------------------------------------------===//
+
+// TODO(CIR): Consider encoding the null value differently and use conditional
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erichkeane wrote:

Agreed with this TODO.  The textual representation of 'null' is a little fragile for me.

https://github.com/llvm/llvm-project/pull/121069