perf: cache the hash calculation for Operand#109
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arirubinstein wants to merge 1 commit intoopen-policy-agent:mainfrom
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perf: cache the hash calculation for Operand#109arirubinstein wants to merge 1 commit intoopen-policy-agent:mainfrom
arirubinstein wants to merge 1 commit intoopen-policy-agent:mainfrom
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koponen
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shomron
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Hi @arirubinstein - I have concerns with the mutability of the type leading to subtle bugs where the cached hash value no longer maps to its identity.
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| hasher.combine(type) | ||
| hasher.combine(value) |
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- Given that
typeandvalueare public and var/mutable, I do not think it is safe to cache the hash value and assume it will never change. - Changes like this should be accompanied with unit tests.
Signed-off-by: Ari Rubinstein <arirubinstein@users.noreply.github.com>
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What code changed, and why?
Operand: Pre-computes the hash value to avoid repeated hashing of OpType (String-backed RawRepresentable) and Value in hot paths like InvocationKey construction.
Every InvocationKey.init call (on every evalCall) now hashes the args array by combining pre-computed ints instead of rehashing String-backed enums. [Operand].hash(into:) goes from O(n * string_hash) to O(n * int_combine)