Re: [boost] Re: big_int, was Re: New file uploaded to boost

From: John Max Skaller (skaller_at_[hidden])
Date: 2001-07-04 14:14:44

helmut.zeisel_at_[hidden] wrote:

> But how do you portable specify the fastest word size?

        You could use C99's 

        uintmax_t

which is the biggest
rather than the fastest.  Or you could use

        uint_fast64_t

on the basis the compiler can generate much better long
operations than you can hope to do in C.

Another solution is to use

        boost_multiple_precision_word_t

and leave it to the configuration system to pick the best 
word size.

        While there is no run-time penalty for using a template,
there's a compile time one. And something much worse: 
you'd be delegating a difficult technical decision to a
non-expert. And something even worse than that: third
party libraries might use different types, so you might
end up with multiple representations that can't interoperate.

-- 
John (Max) Skaller, mailto:skaller_at_[hidden] 
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