From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marc Lehmann <pcg@goof.com>
To: egcs@cygnus.com
Cc: kthomas@gwdg.de
Subject: Re: Optimizations
Date: Sun, 14 Dec 1997 15:14:00 -0000
Message-id: <19971215000809.60319@cerebro.laendle>
References: <199712091751.MAA18879@ronispc.chem.mcgill.ca> <19971210184633.32470@cerebro.laendle> <3493E06C.8EC36185@gwdg.de>
X-SW-Source: 1997-12/msg00811.html

On Sun, Dec 14, 1997 at 02:34:36PM +0100, Philipp Thomas wrote:
> Marc Lehmann wrote:
> > -fschedule-insns is a *loss* on x86 cpu's!
> 
> care to explain why it is a loss (and most probably also -fschedule-insns2)
> ?

AFAIR -fschedule-insns (as opposed to -fschedule-insns2) is normally a loss
sicne the first scheduling pass is done before register allocation, so the
register pressure increases and local/global get's problems. (for fpu code
it _could_ be beneficial, though).

the second scheduling pass is done after register allocation, so no
"new" hardware registers are created.

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    The choice of a GNU generation                        |
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