From mboxrd@z Thu Jan  1 00:00:00 1970
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Date: Fri, 27 Feb 2015 21:37:45 +0100
From: Jan Kiszka <jan.kiszka@siemens.com>
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Subject: Re: [Xenomai] [RFC] Consolidated exception prologue/epiloge for x86
 and ARM
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To: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
Cc: Xenomai <xenomai@xenomai.org>

On 2015-02-27 21:27, Gilles Chanteperdrix wrote:
> On Fri, Feb 27, 2015 at 09:12:14PM +0100, Jan Kiszka wrote:
>> Hi,
>>
>> just pushed a first implementation of the general model that I proposed
>> for exception handling. You can find it at
>>
>> http://git.xenomai.org/ipipe-jki.git/log/?h=queues/trap-rework
> 
> Also, the clean way to pass virtual + physical flags is to use
> arch_mangle_bits. Using two longs (potentially 128 bits then) is
> completely useless since one of the longs simply has one significant
> bit.

The costs of mangling is higher than using two regs for passing that
data as-is, both binary and LOC-wise (tried it). Plus the code is more
readable.

Jan

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