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Re: a question about peephole2

From: Richard Henderson <rth at redhat dot com>
To: zouq <zouqiong at ict dot ac dot cn>
Cc: gcc at gcc dot gnu dot org
Date: Fri, 13 May 2005 11:30:30 -0700
Subject: Re: a question about peephole2
References: <32826.159.226.40.187.1115998636.squirrel@webmail.ict.ac.cn>

On Fri, May 13, 2005 at 11:37:16PM +0800, zouq wrote:
> original program is:
> mul.d $f1, $f1, $f0
> add.d $f2, $f2, $f1
> div.d $f3, $f0, $f1;
> 
> after i compile used my changed gcc, it becomes:
> madd.d $f2, $f1, $0
> div.d  $f3, $f0, $f1
> 
> as you can see, the value of $f1 is wrong!!

Check

  (rtx_equal_p (operands[3], operands[0])
   || peep2_reg_dead_p (2, operands[0]))


r~

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