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Subject: [Qemu-devel] Re: [PATCH 2/2] tcg-s390: New TCG Target.
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To: Aurelien Jarno <aurelien@aurel32.net>
Cc: qemu-devel@nongnu.org, agraf@suse.de

On 06/17/2010 12:40 PM, Aurelien Jarno wrote:
>> +    /* Handle the modifiers.  */
>> +    if (ct & TCG_CT_CONST_NEG) {
>> +        val = -val;
>> +    }
> 
> This "modifier" is only used by subi. Wouldn't it be better to use a
> TCG_CT_CONST_SUBI instead?

Not really.  This negation needs to happen *before* the sign-extension
of TCG_CT_CONST_32 in order to get correct results.

While I could do a CONST_SUBI, I would have to handle CONST_32 again
within the CONST_SUBI clause and I would not consider that better.


r~