How do we best make sure {Int,Word,Float,Double} to {Int,Word,Float,Double} conversions stay efficient

David Terei davidterei at
Sat Dec 15 02:29:33 CET 2012

I believe the testsuite now has support for inspecting assembly
output. Not sure if that would be best for your use case, but
something to consider.

On 14 December 2012 12:53, Johan Tibell <johan.tibell at> wrote:
> Hi,
> I've been tracking down a few (unrelated) performance bugs related to
> conversions between primitive types. What these issues had in common
> is that some rule failed to fire and the conversion went via Integer,
> killing performance. How do we best write a test that make sure that
> fromIntegral conversions between these types don't regress? Is it
> possible to test the output of the simplifier or do we have to do
> something less direct, like writing a loop that does such conversions
> and make sure that the allocation stay low?
> -- Johan
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