[clang] [CIR] Add support for the IdiomRecognizer pass (PR #208854)

[Erich Keane via cfe-commits]

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@@ -1296,11 +1296,52 @@ def CIR_CXXAssignAttr : CIR_Attr<"CXXAssign", "cxx_assign"> {
 // FuncInfoAttr
 //===----------------------------------------------------------------------===//
 
+// The standard library entities the identity tag can name. Each entry
+// pairs with one raised operation in CIRStdOps.td.
+def CIR_KnownFuncKind : CIR_I32EnumAttr<"KnownFuncKind",
+    "known standard library entity", [
+  I32EnumAttrCase<"StdFind", 1, "std_find">,
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erichkeane wrote:

it would be really neat if we could do something like that... would make it a LOT less ambiguous what we really mean by using the term of art.

https://github.com/llvm/llvm-project/pull/208854