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From: John Levine <johnl@taugh.com>
Newsgroups: comp.arch
Subject: Re: Calling conventions (particularly 32-bit ARM)
Date: Wed, 15 Jan 2025 03:31:47 -0000 (UTC)
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According to MitchAlsup1 <mitchalsup@aol.com>:
>> I would think that for Fortran (==everything passed by reference)
>> memory would beat registers most of the time.
>
>Pass by COMMON block was even faster.

Sometimes.  On machines that don't have direct addressing, such as S/360,
the code needs to load a pointer to the data either way so it's a wash.

Even when you do have direct addressing, if code is compiled to be
position indepedent, the common block wouldn't be in the same module
as the code that references it so it still needs to load a pointer
from the GOT or whatever its equivalent is.

-- 
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John Levine, johnl@taugh.com, Primary Perpetrator of "The Internet for Dummies",
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