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Date: Mon, 8 Sep 2014 11:06:01 +0400
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To: Matt Wilmas <php_lists@realplain.com>
Cc: PHP Internals <internals@lists.php.net>
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Subject: Re: zend_mm_small_size_to_bit
From: dmitry@zend.com (Dmitry Stogov)

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Hi Matt,

You are right about zend_mm_small_size_to_bit(). It's result must be
undefined for 0 and corresponding part of non-GCC version may be removed as
well. I'll do it.

Thanks. Dmitry.


On Fri, Sep 5, 2014 at 8:00 PM, Matt Wilmas <php_lists@realplain.com> wrote:

> Hi Dmitry, all,
>
> I was looking through a few parts of the new MM last week (cool, thanks! I
> will try soon on my Windows XP), and wasn't sure about the function in the
> subject...
>
> This:
>
> /* higher set bit number (0->0, 1->1, 2->2, 4->3, 8->4, 127->7, 128->8
> etc) */
> static zend_always_inline int zend_mm_small_size_to_bit(int size)
> {
> #if defined(__GNUC__)
> return (__builtin_clz(size) ^ 0x1f) + 1;
>
> Will never return 0, right? (Against the comment...)  That's OK I guess
> since, for now, it's only called with size >= 8.
>
> But in that case, this can be removed from the non-GCC version:
>
> if (size == 0) return 0;
>
> Shouldn't have just one version able to return 0? :-/  Unless I'm missing
> something!  Let me know...
>
>
> Thanks,
> Matt
>

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