From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <37fc4a190bab010e45ea64a0823cbb29@terzarima.net>
To: 9fans@cse.psu.edu
Subject: Re: [9fans] Install from CD fails
From: Charles Forsyth <forsyth@terzarima.net>
Date: Wed, 19 Apr 2006 14:21:10 +0100
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> If I was looking for ways to reduce space I would probably
> start with vlrt.c and pool.c

the quick linker changes i did this morning discard various
commonly unused functions in vlrt.c, and sometimes in pool.c.
it saves 12% on text and data for something simple like cat.c but as one might
expect it saves less and less as a percentage of
bigger things like plan 9 and inferno kernels (eg 1.4% or so).
i haven't tabulated savings overall.

a few represent obsolete things that could simply be removed,
but in quite a few cases (eg, atexit and canlock below) the relevant source
files have several functions (often to use internal functions and data marked static)
and in any given load some of them aren't used (eg, rc4skip and rc4back in rc4.c).
on the other hand, partly because of the simple-minded implementation,
it adds a bit to the linking time when used, notably on the kernels.

here's the list for cat.c
	atexit unused
	atexitdont unused
	canlock unused
	atoi unused
	_d2v unused
	_f2v unused
	_v2d unused
	_v2f unused
	vneg unused
	_divv unused
	_modv unused
	_rshav unused
	_rshlv unused
	_lshv unused
	_andv unused
	_orv unused
	_xorv unused
	_vpp unused
	_vmm unused
	_ppv unused
	_mmv unused
	_p2v unused
	_sl2v unused
	_ul2v unused
	_si2v unused
	_ui2v unused
	_sh2v unused
	_uh2v unused
	_sc2v unused
	_uc2v unused
	_v2sc unused
	_v2uc unused
	_v2sh unused
	_v2uh unused
	_v2sl unused
	_v2ul unused
	_v2si unused
	_v2ui unused
	_testv unused
	_eqv unused
	_nev unused
	_ltv unused
	_lev unused
	_gtv unused
	_gev unused
	_lov unused
	_lsv unused
	_hiv unused
	_hsv unused
	runenlen unused
	fmtfdflush unused
	fmtinstall unused
	_mulv unused
	_addv unused
	toupper unused
	modf unused
	muldiv unused
	$0.0 unused (data)
but that amounts to only 2844 bytes overall of the original 23110.
by the time you get to the kernels, you're talking real savings of, ooh, 30k
out of 1.7mbytes (text+data+bss).  it's slightly more helpful with inferno
than plan 9, because the kernel includes more library code, and sometimes that
includes functions that could be called to dump data structures when debugging
but aren't referenced normally.