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Re: [RFC] PowerPC sCC patterns

From: David Edelsohn <dje at watson dot ibm dot com>
To: gcc-patches at gcc dot gnu dot org
Date: Wed, 24 Nov 2004 13:01:44 -0500
Subject: Re: [RFC] PowerPC sCC patterns
References: <200411082304.iA8N48D32314@makai.watson.ibm.com> <20041124105335.GB15036@bubble.modra.org>

	The mode test is because the SCC patterns that do not use CRs
often use carry, which only exists when mode matches Pmode.  The EQ. LTU,
GTU test exists because those are the non-CR patterns supported by
PowerPC (POWER architecture was intentionally ignored to avoid complexity).

	The revised cost model needs to preserve the existing costs for
arbitrary CONST_INT and add cases for any SCC comparison with const0_rtx.

David

References:
- [RFC] PowerPC sCC patterns
  - From: David Edelsohn
- Re: [RFC] PowerPC sCC patterns
  - From: Alan Modra

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