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Subject: Re: [boost] [Review] Boost.Endian mini-review
From: Beman Dawes (bdawes_at_[hidden])
Date: 2015-01-26 08:03:52


On Sun, Jan 25, 2015 at 6:12 PM, Jason Newton <nevion_at_[hidden]> wrote:
> On Sun, Jan 25, 2015 at 8:21 AM, Beman Dawes <bdawes_at_[hidden]> wrote:
>
>> On Sat, Jan 24, 2015 at 2:25 AM, Jason Newton <nevion_at_[hidden]> wrote:
>> > I think the only thing that I have no interest in using - a kind way of
>> > saying its probably unneeded bloat IMO is the arithmetic types. I prefer
>> > native types and using conversion functions. But maybe they could
>> improve
>> > my code - its something I toss back and forth a little and haven't
>> > attempted embracing.
>>
>> Because even the endian buffer and arithmetic types that appear most
>> expensive generate only short sequences of code, the optimizing
>> compilers often generate exactly the same instructions regardless of
>> endian approach. On Intel machines, that often distills down to a
>> single bswap instruction since the value is already in a register.
>>
>> That isn't always true, so you do need to measure performance of
>> various approaches in the context of your actual application. But if
>> use of the buffer or arithmetic types would otherwise improve your
>> code, please don't reject them without actually testing performance
>> first.
>>
>
> Allow me to clarify: I meant code bloat, not speed.

Sorry - your original post was clear, but I misinterpreted.

I have not systematically measured code bloat. Maybe I can do that at
least for some common use cases.

Thanks,

--Beman


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