Avoid calling CanMemberSigsMatchUpToCheck twice #1685
Merged
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By upgrading the undo trace to an undo/redo trace we may avoid calling
CanMemberSigsMatchUpToCheck
twice in a common scenario.If the second call to
FilterEachThenUndo
(the one for applicable methods) was performed then we can collect the effects of the call toCanMemberSigsMatchUpToCheck
and avoid calling it again in the final checks.The only difference between these two calls is the
alwaysCheckReturn
parameter which in the final checks must always be true, but that check can be performed by-hand after re-playing the trace.Here's a crazy-compile-time-test with the following results:
So in this case it will speed up 30x but it's clear that the speed up is exponential, so it will depend on the level of nesting.
For simple and no nested cases it's expected at least a 90% of the original time.
No other effect is expected since the modified code is equivalent to the original.