Re: [v3] Print ints directly to streambuf

[Nathan Myers <ncm-nospam at cantrip dot org>]

On Tue, Feb 25, 2003 at 04:45:36PM -0800, Richard Henderson wrote:
> On Tue, Feb 25, 2003 at 04:26:12PM -0800, Nathan Myers wrote:
> > I wonder how often this is faster.   Probably we can identify targets 
> > where it is, and add a flag in config.h.  (In practice, most numbers 
> > are small, although maybe not most hex-formatted numbers.)
> 
> Dunno.  Definitely faster on i386, ia64, ppc, arm, alphaev67.
> 
> For others we get out-of-line code; dunno how much slower that
> might be.  We could perhaps re-instate some ifdeffing such 
> that the out of line code did a binary search for the correct
> value (I'd removed that as hairy to get right).

I find that compiling a function that mentions __builtin_clz just 
results in an "undeclared identifier" error report.  I have been 
searching in the gcc sources for any indication of support for 
__builtin_clz.  

I find gcc/longlong.h, but that doesn't get installed for user code.  
Are you suggesting that we copy the (uglified) contents gcc/longlong.h 
into the set of headers released with libstdc++?  Most likely users 
would like to have those functions ready to hand.

Nathan Myers
ncm-nospam at cantrip dot org