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Subject: Re: inline assembly & r0 SOS
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Kevin Diggs <kevdig@hypersurf.com>
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Date: Wed, 06 Aug 2008 10:35:07 +1000
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On Tue, 2008-08-05 at 17:20 -0700, Kevin Diggs wrote:
> Hi,
> 

> thats bad right? Because the "addi 0, 0, 23" will not work as expected 
> because of the "special property" of r0. FYI:  The first three lines 
> after the "#APP" are from a similar function get_PLL_ratio().
> 
> 	Is there a way to blacklist r0?

Yes. Use "b" instead of "r" in the constraints to force the compiler
to avoid r0 when assigning a register.

Cheers,
Ben.