Poor performance of division; unnecessary branching
In case an Int* is divided by a constant the compiled code contains unnecessary checks whether the value being divided is minBound. This check is necessary only if a value is being divided by -1 so that an exception would be thrown.
The branch can be removed by the GHC's optimiser after a small change: the two parts of the corresponding condition have to be flipped. This provides an opportunity to short-circuit this condition to 'false' without knowing the first argument (patch is attached).
Trac metadata
Trac field | Value |
---|---|
Version | 7.0.3 |
Type | Bug |
TypeOfFailure | OtherFailure |
Priority | normal |
Resolution | Unresolved |
Component | libraries/base |
Test case | |
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