[fpc-devel] Generated code of constant parameters of double type
florian at freepascal.org
Sun Nov 16 19:08:05 CET 2008
Luiz Americo Pereira Camara schrieb:
> Florian Klaempfl escreveu:
>> Luiz Americo Pereira Camara schrieb:
>>> My point was that this could be a missing optimization opportunity:
>>> pass by reference a 8 bytes parameter when the pointer size is 4.
>> Don't forget that this makes an extra memory access.
> I will do my question in a simpler way:
> Using constant parameters (add const keyword in front of an argument) is
> beneficial for record types with size > pointer size and for string
> types but not for integer and pointer types.
No, this is not necessarily true. The extra indirect can be also slower.
> Currently is not beneficial for double types and there's no way to
> improve that. So when developing an interface that uses double types
> does not matter using const or not. Now and in the future. Right?
It might matter for the optimizer in other situations.
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