[clang] [CIR] Handle __declspec(noalias) as argmem side effects (PR #221819)

[Konstantinos Parasyris via cfe-commits]

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@@ -1913,11 +1871,12 @@ def CIR_BlockAddrDiffAttr
 // Side Effect
 //===----------------------------------------------------------------------===//
 
-def CIR_SideEffect : CIR_I32Enum<
+def CIR_SideEffect : CIR_I32EnumAttr<
     "SideEffect", "allowed side effects of a function", [
       I32EnumAttrCase<"All", 0, "all">,
       I32EnumAttrCase<"Pure", 1, "pure">,
-      I32EnumAttrCase<"Const", 2, "const">
+      I32EnumAttrCase<"Const", 2, "const">,
+      I32EnumAttrCase<"ArgMem", 4, "argmem">
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koparasy wrote:

Why not 3?

https://github.com/llvm/llvm-project/pull/221819