Re: [boost] [xint] Third release is ready, requesting preliminary review

Subject: Re: [boost] [xint] Third release is ready, requesting preliminary review
From: vicente.botet (vicente.botet_at_[hidden])
Date: 2010-05-02 13:13:45

----- Original Message ----- 
From: "Chad Nelson" <chad.thecomfychair_at_[hidden]>
To: <boost_at_[hidden]>
Sent: Sunday, May 02, 2010 7:02 PM
Subject: Re: [boost] [xint] Third release is ready, requesting preliminary review

> 
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> On 05/02/2010 12:05 PM, vicente.botet wrote:
>> On the documentation you say " Some of these numbers can get huge, 
>> making copying an expensive proposition, and even move semantics (at 
>> least as emulated by Boost.Move at the time of this writing) aren't
>> as fast"
>> 
>> Why do you say on Boost.Move is not as fast as COW?
> 
> Because it isn't. I ran some tests when I added Boost.Move to it, and
> copy-on-write is measurably faster than (emulated) move semantics, by
> about the same amount that emulated move semantics are faster than not
> having either. I'm hoping that compiler-supported move semantics will be
> equal to copy-on-write, but until they're widely available,
> copy-on-write is better.

Are you saying that given the following functions

xint::integer cow();
boost::rv<xint::integer> m();
xint::integer i;

i = cow() is faster than i = m() on a single thread environement?

If yet, what is the ratio you have measured?

Best,
Vicente