From:	ggerard AT iname DOT com (Gregory Gerard)
Newsgroups:	comp.os.msdos.djgpp
Subject:	question about inline asm not answered in FAQs (or pseudo FAQs)
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Date:	Thu, 04 Nov 1999 00:07:38 -0800
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To:	djgpp AT delorie DOT com
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Reply-To:	djgpp AT delorie DOT com

I could not find the answer in any of the FAQs I've seen floating around
which cover the subject of inline asm in gcc, nor could I find the answer
in the docs, so I thought I'd ask here.  I may be blind though...

okay, one of the inputs to my __asm__() block is a unsigned char (1 byte)
in position 0.  I can refer to the upper and lower portions of the
register that got assigned by saying %b0 and %h0 and the register as word
by saying %w0.  However, when I go to do a 32-bit op (say, shll %16, %0),
I get an error because %0 gets plugged as %bl.

I learned about %w, %h, and %b by looking at other asm examples but I
haven't come accross any code that has this situation and I can extract
the key.  What's the answer and where do I find full descriptions of how
inline asm is done with a target of i386 (the 68k examples in the GNU docs
are pretty weak.)

thanks,
greg

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