[llvm] Add the 'initialized' attribute langref and support (PR #84803)

[Jan Voung via llvm-commits]

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@@ -2364,6 +2381,54 @@ bool LLParser::parseOptionalDerefAttrBytes(lltok::Kind AttrKind,
   return false;
 }
 
+bool LLParser::parseConstRange(std::pair<int64_t, int64_t> &Range) {
+  LocTy LparenLoc = Lex.getLoc();
+  if (!EatIfPresent(lltok::lparen))
+    return error(LparenLoc, "expected'('");
+
+  if (parseInt64(Range.first))
+    return true;
+
+  if (EatIfPresent(lltok::comma)) {
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jvoung wrote:

should it be an error to be missing the comma?

https://github.com/llvm/llvm-project/pull/84803