perf: cache swizzled selector construction #173
Merged
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Checking if a swizzled method exists constructs the selector for every call by concatenating the swizzle prefix to the actual selector string. This is pretty slow when doing many calls.
This PR keeps a map (using robin_hood::unordered_map for performance) of SEL (selector) pairs, so that the swizzled selector is only constructed once, and any subsequent calls will use the fast-path by returning the value from the cache.
From a few performance tests, we've seen a ~30% improvement, though it may vary from case to case.