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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups: comp.arch
Subject: Re: Calling conventions (particularly 32-bit ARM)
Date: Mon, 27 Jan 2025 17:09:59 -0800
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George Neuner <gneuner2@comcast.net> writes:

> On Mon, 6 Jan 2025 20:10:13 +0000, mitchalsup@aol.com (MitchAlsup1)
> wrote:
>
>> I looked high and low for codes using more than 8 arguments and
>> returning aggregates larger than 8 double words, and about the
>> only things I found were a handful of []print[]() calls.
>
> Large numbers of parameters may be generated either by closure
> conversion or by lambda lifting.  These are FP language
> transformations that are analogous to, but potentially more complex
> than, the rewriting of object methods and their call sites to pass the
> current object in an OO language.
>
> [The difference between closure conversion and lambda lifting is the
> scope of the tranformation:  conversion limits code transformations to
> within the defining call chain, whereas lifting pulls the closure to
> top level making it (at least potentially) globally available.]
>
> In either case the original function is rewritten such that non-local
> variables can be passed as parameters.  The function's code must be
> altered to access the non-locals - either directly as explicit
> individual parameters, or by indexing from a pointer to an environment
> data structure.
>
> While in a simple case this could look exactly like the OO method
> transformation, recall that a general closure may require access to
> non-local variables spread through multiple environments.  Even if
> whole environments are passed via single pointers, there still may
> need to be multiple parameters added.

Isn't it the case that access to all of the enclosing environments
can be provided by passing a single pointer?  I'm pretty sure it
is.