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Re: [rtl] Optimization question.

To: Oleg Subbotin <oleg@rtlinux.cs.nmt.edu>
Subject: Re: [rtl] Optimization question.
From: "Heo, Sung Gwan" <heo@nextin.co.kr>
Date: Mon, 13 Jul 1998 09:31:52 +0900
CC: rtl@rtlinux.cs.nmt.edu
Organization: Turbo-Tek Co., Ltd.
References: <Pine.LNX.3.96.980712114956.8077B-100000@rtlinux.cs.nmt.edu>

Oleg Subbotin wrote:
> 
>         testb $1,%al               <--Instead of logical AND gcc generate testb
>         jne .L2                    <--But for test==3,5,7... it will not work
> 

You wrote the C code that does 'bit-wise AND', not 'logical AND'.
i.e (temp & ONE), not (temp && ONE).

Of course, testb instruction performs 'bit-wise AND'.


Good Day!

Heo, Sung Gwan.
-- 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Heo, Sung Gwan                         mailto:heo@nextin.co.kr
R&D, Turbo-Tek Co., Ltd.               http://www.turbotek.co.kr
3F, Dooin Bldg. 16-6 Sunae-Dong,       Phone:  (0342) 718-5166
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--- [rtl] ---
For more information on Real-Time Linux see:
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References:
- [rtl] Optimization question.
  - From: Oleg Subbotin <oleg@rtlinux.cs.nmt.edu>

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