From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andreas Schwab <schwab@linux-m68k.org>
Subject: Re: atomic_sub_and_test() asm constraints
Date: Sun, 14 Mar 2010 15:30:51 +0100
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References: <10f740e81003140559y7692c30ena811b6c0283c2303@mail.gmail.com>
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In-Reply-To: <10f740e81003140559y7692c30ena811b6c0283c2303@mail.gmail.com>
	(Geert Uytterhoeven's message of "Sun, 14 Mar 2010 13:59:06 +0100")
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To: Geert Uytterhoeven <geert@linux-m68k.org>
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Geert Uytterhoeven <geert@linux-m68k.org> writes:

> |   CC      mm/memcontrol.o
> | {standard input}: Assembler messages:
> | {standard input}:4076: Error: operands mismatch -- statement `subl
> 12(%fp),170(%a0)' ignored
>
> Seems like we have bad asm constraints in
>
> static inline int atomic_sub_and_test(int i, atomic_t *v)
> {
>         char c;
>         __asm__ __volatile__("subl %2,%1; seq %0" : "=d" (c), "+m"
> (*v): "g" (i));

Surely "g" is wrong, sub only accepts a data register as source operand
when the destination is in memory.

Andreas.

-- 
Andreas Schwab, schwab@linux-m68k.org
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