[llvm] [UpdateTestChecks] Add --filter/--filter-out support to update_mir_test_checks.py (PR #191059)

[Sebastian Neubauer via llvm-commits]

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@@ -84,6 +84,8 @@ def build_function_info_dictionary(
                 )
             mangled.append(func_line)
         body = "".join(mangled)
+        if filters:
+            body = common.do_filter(body, filters)
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Flakebi wrote:

nit: No need for the `if`, `do_filter` does that check internally as well (the other place calling do_filter does not check for this either).

https://github.com/llvm/llvm-project/pull/191059