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Re: Optimized program four times slower.

From: NightStrike <nightstrike at gmail dot com>
To: tprince at computer dot org
Cc: gcc-help at gcc dot gnu dot org, "Sebastien M." <ploouuf at yahoo dot fr>
Date: Sat, 14 Jul 2007 22:14:41 -0400
Subject: Re: Optimized program four times slower.
References: <f7b493$6vb$1@sea.gmane.org> <46997352.34D697AD@dessent.net> <46997F45.9020402@myrealbox.com>

On 7/14/07, Tim Prince <tprince@myrealbox.com> wrote:

Brian Dessent wrote:

you should file a PR.  Note that dec, rather than add -1, has been a
standard way to write code which might be OK on AMD but dead slow on
Intel, since 6 years ago.

Why is add -1 slower than dec?

Follow-Ups:
- Re: Optimized program four times slower.
  - From: Tim Prince

References:
- Optimized program four times slower.
  - From: Sebastien M.
- Re: Optimized program four times slower.
  - From: Brian Dessent
- Re: Optimized program four times slower.
  - From: Tim Prince

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