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Re: [4.0 and mainline] Fix multiplication by constant expansion

From: Jan Hubicka <jh at suse dot cz>
To: Jan Hubicka <jh at suse dot cz>
Cc: Roger Sayle <roger at eyesopen dot com>, David Edelsohn <dje at watson dot ibm dot com>, gcc-patches at gcc dot gnu dot org
Date: Mon, 2 Jan 2006 20:02:02 +0100
Subject: Re: [4.0 and mainline] Fix multiplication by constant expansion
References: <20060102001751.GH4110@kam.mff.cuni.cz> <Pine.LNX.4.44.0601011643520.30956-100000@www.eyesopen.com> <20060102155128.GO4110@kam.mff.cuni.cz>

> I am going to try 3 address arechitecture (PPC) and P4 with decomposed leas, but things are somewhat contraintuitive here.

On power4 after hacking "mult" instruction to higher cost as currently
it is so low that we never get into interesting expansion, I get 14%
regression for my hack, so it seems to work there.

Honza

References:
- Re: [4.0 and mainline] Fix multiplication by constant expansion
  - From: Jan Hubicka
- Re: [4.0 and mainline] Fix multiplication by constant expansion
  - From: Roger Sayle
- Re: [4.0 and mainline] Fix multiplication by constant expansion
  - From: Jan Hubicka

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