python / python/mypy

Speed up TypeQuery

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#7,128 6 comments 0 reactions 1 assignee View on GitHub

@JukkaL is already working on this.

Since Dec 12, 2022.

performance priority-1-normal
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Python
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Description

mypy.type_visitor.TypeQuery is constructed often with the any or all builtin function as an argument. The function is used as a callable inside the query. Calling callable variables is kind of slow when compiled with mypyc. Since type queries are used a lot, switching to an integer constant or a compiled object instead of a callable could speed up runtimes measurably, perhaps by as much as 0.5% or so (random guess). Since the optimization is pretty simple, this may be worth doing.

Discussion:

  • Maybe have separate type query visitor which produces boolean values. The strategy could be specified as an integer constant.
  • For non-bool type queries, experiment with using an object instead of a callable for the strategy, since callables are currently pretty slow when compiled.
  • Maybe also special case self.strategy([]) since it's used a lot.

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