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To: "Paulo J. Matos" <pocmatos@gmail.com>
Cc: gcc@gcc.gnu.org
Subject: Re: Clobbering two registers
References: <AANLkTinEaz7duLhA38ozWqOLlH_CuwWbKUmb_tT2D0JE@mail.gmail.com>
From: Ian Lance Taylor <iant@google.com>
Date: Wed, 12 May 2010 17:47:00 -0000
In-Reply-To: <AANLkTinEaz7duLhA38ozWqOLlH_CuwWbKUmb_tT2D0JE@mail.gmail.com> (Paulo J. Matos's message of "Wed\, 12 May 2010 17\:17\:23 +0100")
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"Paulo J. Matos" <pocmatos@gmail.com> writes:

> How can I say in the machine architecture that to generate code for a
> particular insn I need any two registers for intermediate operations?
> To get one I think that (clobber (match_operand ...)) will work but
> what if I want two? Can I add two clobbers on the same define_insn
> rule?

Yes.

Also look at match_scratch.

Ian