From:	Hans-Bernhard Broeker <broeker AT physik DOT rwth-aachen DOT de>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Inline Assembly and return value of a function
Date:	31 Jul 2002 07:50:42 GMT
Organization:	Aachen University of Technology (RWTH)
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Martin Steuer <martinSteuer AT gmx DOT de> wrote:
>     __asm__ __volatile(
>             "bswapl %1\n"
>             : "=r"(swapped)
>             : "r"(v)
>             );

> Now the problem: the return statement doesnt move the result of bswap() 
> into eax, thus some garbage is returned.

You're not telling GCC that 'swapped' is supposed to be in the same
register as 'v'.  I think you had best get rid of 'swapped'
altogether.  Either that, or do as the Linux code snippet posted by
DJ: reference the input register in the output specification, so GCC
knows these two registers are supposed to be the same.
-- 
Hans-Bernhard Broeker (broeker AT physik DOT rwth-aachen DOT de)
Even if all the snow were burnt, ashes would remain.

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