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Date: Wed, 15 Jan 2003 17:37:00 -0000
Subject: Re: optimizations
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Cc: Andrew Pinski <pinskia@physics.uc.edu>, gcc-help <gcc-help@gcc.gnu.org>,
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To: Reza Roboubi <reza@linisoft.com>
From: Andrew Pinski <pinskia@physics.uc.edu>
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On Tuesday, Jan 14, 2003, at 16:49 US/Pacific, Reza Roboubi wrote:

> Could you please also tell me if 3.3 and 3.4 remove the extra mov's in 
> and out
> of %eax. Ideally, there should be no more than 4 instructions in the 
> critical
> loop.
>

For some reason it is not (even with -fnew-ra), but on PPC there is no 
extra load/store.

Thanks,
Andrew Pinski


PS here is the asm for the loop of i[3-6]686, pentium4:

.L2:
         movl    -4(%ebp), %eax  <== still does the store
         cmpl    $16, %eax
         je      .L7
         incl    %eax
         movl    %eax, -4(%ebp) <== and load
         jmp     .L2
.L7:

I do not have access to the machine with 3.{3,4} on PPC right now.