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Date: Thu, 1 Mar 2012 08:22:23 -0800 (PST)
Reply-To: Adi Mutu <adi_mutu06@yahoo.com>
To: PHP Developers Mailing List <internals@lists.php.net>
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Subject: question about Zend MM 
From: adi_mutu06@yahoo.com (Adi Mutu)

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Hello,

I want to understand how Zend MM works, so i'm looking trought the sources and i see this:

#define ZEND_MM_ALIGNMENT_MASK ~(ZEND_MM_ALIGNMENT-1) #define ZEND_MM_ALIGNED_SIZE(size)	(((size) + ZEND_MM_ALIGNMENT - 1) & ZEND_MM_ALIGNMENT_MASK) 


I understand that the first define will create something like 11111000 ( it will clear last 3 bits)
but what does the 2nd define? Before clearing the last 3 bytes why does it add ZEND_MM_ALIGNMENT- 1
to size?

Thanks,
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