[LLVM] Accept `noundef` attribute in function definitions/calls
The `noundef` attribute indicates an argument or return value which
may never have an undef value representation.
This patch allows LLVM to parse the attribute.
Differential Revision: https://reviews.llvm.org/D83412
diff --git a/llvm/lib/AsmParser/LLLexer.cpp b/llvm/lib/AsmParser/LLLexer.cpp
index 2a39e19..777ce3a 100644
--- a/llvm/lib/AsmParser/LLLexer.cpp
+++ b/llvm/lib/AsmParser/LLLexer.cpp
@@ -664,6 +664,7 @@
KEYWORD(noreturn);
KEYWORD(nosync);
KEYWORD(nocf_check);
+ KEYWORD(noundef);
KEYWORD(nounwind);
KEYWORD(null_pointer_is_valid);
KEYWORD(optforfuzzing);