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Date: Thu, 16 Sep 2010 12:14:06 +0200
From: Jes Sorensen <Jes.Sorensen@redhat.com>
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Subject: [Qemu-devel] Re: [PATCH 2/5] Support human unit formats in
	strtobytes, eg. 1.0G
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To: Paolo Bonzini <pbonzini@redhat.com>
Cc: quintela@redhat.com, qemu-devel@nongnu.org, armbru@redhat.com

On 09/16/10 09:19, Paolo Bonzini wrote:
> On 09/15/2010 09:31 PM, Jes Sorensen wrote:
>> Floating point is just plain wrong. If someone wants to do something
>> like in your example they really ask for an error.
> 
> An error, not an overflow.
> 
> Adding overflow checking on top of your patch is also fine.  Another
> possibility is to look ahead for the multiplier so that you correctly
> base the divider and do everything in 64.64 fixed point.  But it seems
> overkill compared to floating-point, whose 53-bit mantissa precision
> will almost always lead to exact results (large numbers usually have a
> lot of zeros at the end, both in binary and in decimal).

I think it would be quite reasonable not to accept anything more than
say 3-4 decimal points, since there are the t/g/m/k options as well.

Cheers,
Jes