[llvm] [utils][filecheck-lint]: speedup filecheck_lint (PR #94191)

[Benjamin Chetioui via llvm-commits]

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@@ -228,7 +237,8 @@ def find_best_match(typo):
         )
 
     potential_directives = find_potential_directives(content)
-
+    # cache score and best_match to skip recalculating
+    checked_potential_directives = dict()
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bchetioui wrote:

nit: it's not super obvious to me what this variable contains based on its name.

How about `score_and_best_match_for_potential_directive`? (A bit of a mouthful.)

https://github.com/llvm/llvm-project/pull/94191