Newsgroups: comp.sys.transputer
From: Michael Haardt <(michael)u31b3hs@pool.informatik.rwth-aachen.de>
Subject: Performance gain by reordering modules before linking?
Keywords: prefix length, linker
Organization: An old and gray machine, somewhere in Moria.
Date: Sun, 16 Jan 94 18:18:40 MET
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Message-ID: <9401161101@gandalf.moria>

Has someone done research for algorithms which reorder object modules
before linking to minimise the length of nfix/pfix sequences?  Are there
any ideas about speed and size improvements which might be gained by
this?  What are strategies of ordering modules for commercial linkers?

I wonder if it is worth the trouble, and what are common techniques,
because I can't remember of ever having read something about it.

Further, do commercial compilers/assemblers/linkers use jump tables for
calls between modules, or are all operands converted to prefix sequences
at link time?  I read about that in "Compiler Writer's Guide", but I
didn't understand the advantage apart from link time savings, which
can't be that essential.  (The described algorithm needs only 10 passes
to build a real world program with 170k code _without_ using stubs.)

Michael
--
Twiggs and root are a wonderful tree (tm) Twiggs & root 1992 :-)

