Re: global variables in registers, esp. on [34]86?

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Article #52134

#52134

From: James Van Artsdalen
Date: Sun, 07 Feb 1993 22:16

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In <9302011508.AA05344@life.ai.mit.edu>,
	partain@dcs.gla.ac.UK (Will Partain) wrote:

> What registers can you get away with stealing on a [34]86?  Some of my
> Linux-toting friends say "none", which is a depressing thought.

You can probably get away with using %ebx for a register variable.
But every other register is individually needed by at least one pattern
due to the architecture of the x86.

PIC code for SysVr4/386 works by "stealing" %ebx, so you can't even
use %ebx with -fpic.
-- 
-- 
James R. Van Artsdalen          james@bigtex.cactus.org   "Live Free or Die"
Dell Computer Co    9505 Arboretum Blvd Austin TX 78759         512-338-8789

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From: james@raid.dell.com (James Van Artsdalen)
Subject: Re: global variables in registers, esp. on [34]86?
Message-ID: <1993Feb7.221606.28526@raid.dell.com>
Reply-To: james@raid.cactus.org (James Van Artsdalen)
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Date: Sun, 7 Feb 1993 22:16:06 GMT
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