Re: [boost] [Review] Boost.Endian mini-review

Subject: Re: [boost] [Review] Boost.Endian mini-review
From: Peter Dimov (lists_at_[hidden])
Date: 2015-01-24 11:09:39

> This approach - as shown - does have a drawback. If you have an array of 
> 802511 32 bit lsb integers in the file, and the native int is 32 bit lsb, 
> one read of 802511*4 bytes is vastly superior in performance to a loop 
> that would read 4 bytes and call read_32_lsb on the byte[4]. Which is why 
> the above is generally combined with
>
>     void read_32_lsb_n( int * first, int * last, FILE * fp );

It occurs to me that the library could benefit from similar additions to 
little_to_native et al, which are currently scalar-only and would, 
therefore, depend on a Sufficiently Smart(tm) compiler to optimize out the 
empty calls.

Batch endianness fixups are very common and very performance sensitive.