Re: 386 Assembler Question - Easy one... - Article 6321 - go-pugleaf

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Re: 386 Assembler Question - Easy one...

#6321

From: Brad Levy
Date: Tue, 17 Nov 1992 06:01

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> In <1992Nov9.162931.1@camins.camosun.bc.ca> morley@camins.camosun.bc.ca writes:
>In 386 assembler I need to fill an extended register with 4 copies
>of the same byte.  Right now I'm using the following:
> 
>   mov  al,VALUE
>   mov  ah,VALUE
>   shl  eax,16
>   mov  al,VALUE
>   mov  ah,VALUE
> 
>I'm curious... is there a better/faster way to stuff the register?

If VALUE is a constant, the fastest would be:

   mov   eax, VALUEVALUEVALUEVALUE
i.e., an immediate 32-bit load.    

- brad

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Message-ID: <1992Nov17.060124.11423@informix.com>

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<1992Nov9.162931.1@camins.camosun.bc.ca> <1992Nov11.114831.6643@ufhx1.ufh.ac.za> <1992Nov12.145342.17642@merlin.dev.cdx.mot.com>

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Path: arc1-ca.pugleaf.net!sparky!uunet!cis.ohio-state.edu!pacific.mps.ohio-state.edu!linac!uwm.edu!cs.utexas.edu!sun-barr!olivea!gossip.pyramid.com!pyramid!infmx!neptune!bradl
From: bradl@neptune.informix.com (Brad Levy)
Newsgroups: comp.os.msdos.programmer
Subject: Re: 386 Assembler Question - Easy one...
Message-ID: <1992Nov17.060124.11423@informix.com>
Date: 17 Nov 92 06:01:24 GMT
References: <1992Nov9.162931.1@camins.camosun.bc.ca> <1992Nov11.114831.6643@ufhx1.ufh.ac.za> <1992Nov12.145342.17642@merlin.dev.cdx.mot.com>
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