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Date:      Tue, 06 Aug 2002 17:14:07 -0700
From:      Darren Pilgrim <dmp@pantherdragon.org>
To:        Peter Wemm <peter@wemm.org>
Cc:        Matthew Dillon <dillon@apollo.backplane.com>, Dan Nelson <dnelson@allantgroup.com>, Terry Lambert <tlambert2@mindspring.com>, Jason Andresen <jandrese@mitre.org>, Dmitry Morozovsky <marck@rinet.ru>, hackers@FreeBSD.ORG
Subject:   Re: -fomit-frame-pointer for the world build
Message-ID:  <3D50664F.71603B49@pantherdragon.org>
References:  <20020806214833.705D32A7D6@canning.wemm.org>

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Peter Wemm wrote:
> Far more speed benefit can be had by setting -mcpu/-march/-mtune
> *correctly* than things like -fomit-frame-pointer will do.  For example, 32
> bit multiply is REALLY slow on i386 (our default target until recently) so
> gcc will try and "optimize" out multiplies by converting them to shift/add.
> Of course, this turns out to usually be slower on pentium and above. :-]

How do Intel's "Overdrive" processors fit in?  I have one machine that
has a Pentium Pro Overdrive processor.  Do I set CPU=i686 or CPU=p2 in
this case?  Here's kernel line for the CPU:

CPU: Overdrive Pentium II/Pentium II Xeon/Celeron (332.39-MHz 686-class CPU)
  Origin = "GenuineIntel"  Id = 0x1631  Stepping = 1
  Features=0x183f9ff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,MMX,FXSR>

I would assume CPU=p2, but I also know that what's in the ceramic
casing isn't a standard Pentium II.

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