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Mail Archives: djgpp/1996/12/27/07:50:14

From: ovek AT arcticnet DOT no (Ove Kaaven)
Newsgroups: comp.os.msdos.djgpp
Subject: Re: 32 bit registers
Date: Thu, 26 Dec 1996 22:27:18 GMT
Organization: Vplan Programvare AS
Lines: 18
Message-ID: <59vm0n$7gu$1@troll.powertech.no>
References: <59cs4f$58k AT nr1 DOT ottawa DOT istar DOT net> <19961224 DOT 142048 DOT 4751 DOT 1 DOT chambersb AT juno DOT com> <59t1qo$tv0$1 AT troll DOT powertech DOT no> <Pine DOT SGI DOT 3 DOT 91 DOT 961226120517 DOT 2924F-100000 AT chinook DOT physics DOT utoronto DOT ca>
NNTP-Posting-Host: alwayscold.darkness.arcticnet.no
To: djgpp AT delorie DOT com
DJ-Gateway: from newsgroup comp.os.msdos.djgpp

Peter Berdeklis <peter AT atmosp DOT physics DOT utoronto DOT ca> wrote:

>On Thu, 26 Dec 1996, Ove Kaaven wrote:
>> To load the 16-bit value in bx into the high-order word of eax and
>> preserving everything else, you could try:
>> 
>> roll $16,%eax
>> movw %bx,%ax
>> roll $16,%eax
>       ^^^ should be $17

>roll moves the last bit into the carry flag, so you have to roll one more 
>bit (the last time only) to get the bit out of the carry flag and into 
>the MSB of the register.

Really? I thought that was the behaviour of rcl, not rol, hmm...


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