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From: Simon Clubley <clubley@remove_me.eisner.decus.org-Earth.UFP>
Newsgroups: comp.lang.ada
Subject: Re: Forcing GNAT to use 32-bit load/store instructions on ARM?
Date: Thu, 10 Jul 2014 13:06:01 +0000 (UTC)
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Date: 2014-07-10T13:06:01+00:00
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On 2014-07-10, Simon Wright <simon@pushface.org> wrote:
> Simon Wright <simon@pushface.org> writes:
>
>> The x86_64 code accesses all 32 bits of V. If it is more efficient on
>> arm to access the relevant bytes for the component assignments, I
>> expect that's what would happen (as reported).
>
> Just tried this on Raspberry Pi (GCC 4.6.3): yes, it only accesses the
> relevant bytes.

Just to make sure: you mean it uses ldrb/strb instead of ldr/str
in the generated code ?

Thanks,

Simon.

-- 
Simon Clubley, clubley@remove_me.eisner.decus.org-Earth.UFP
Microsoft: Bringing you 1980s technology to a 21st century world