[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
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bchetioui wrote:

nit: `[C]ache score and best_match to skip recalculating[.]`

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