[boost] [block_ptr] 20% speed boost

Subject: [boost] [block_ptr] 20% speed boost
From: Phil Bouchard (philippeb8_at_[hidden])
Date: 2016-02-16 19:09:18

 > If I try out the latest modifications and I disable the threads then on
 > Linux I have:
 >
 > make:
 > auto_ptr:                    2458626 ns
 > shared_ptr:                  2685224 ns
 > block_ptr:                  28300624 ns
 >
 > new:
 > auto_ptr:                    2383605 ns
 > shared_ptr:                  4992185 ns
 > block_ptr:                   7979659 ns

So I just added a specialization of the pool for GCC x86 and now 
block_ptr<> speeds up by 20%:

make:
auto_ptr: 2511658 ns
shared_ptr: 2695469 ns
block_ptr: 22547960 ns

new:
auto_ptr: 2369312 ns
shared_ptr: 4991352 ns
block_ptr: 6443925 ns

Thanks,
-Phil