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From: Andreas Schwab <schwab@suse.de>
To: Frank van Maarseveen <frankvm@frankvm.com>
References: <20050715160115.GA22990@janus>
Date: Fri, 15 Jul 2005 20:22:53 +0200
In-Reply-To: <20050715160115.GA22990@janus> (Frank van Maarseveen's message of
	"Fri, 15 Jul 2005 18:01:15 +0200")
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Cc: linuxppc-dev@ozlabs.org
Subject: Re: bug in arch/ppc/kernel/misc.S: __ashrdi3?
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Frank van Maarseveen <frankvm@frankvm.com> writes:

> I don't really grok the code but an operand seems to be missing and the
> assembler makes something out of it I don't trust:
>
> _GLOBAL(__ashrdi3)
> 	...
> 	rlwinm  r8,r7,0,32      # t3 = (count < 32) ? 32 : 0

32 == 0x80000000 >> 26

> 00000000 <f>:
> f():
>    0:   54 e8 06 b4     rlwinm  r8,r7,0,26,26

The mask begins at bit 26 and ends at bit 26 (counted from the left).

Andreas.

-- 
Andreas Schwab, SuSE Labs, schwab@suse.de
SuSE Linux Products GmbH, Maxfeldstraße 5, 90409 Nürnberg, Germany
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