RFC: target macro->hook migration idea

[Joseph S. Myers]

On Tue, 22 Jul 2003, Zack Weinberg wrote:

> > Some methodology needs working out for what should be a macro and
> > what should be a function.  I presume that e.g. the basic macros for
> > type sizes (that generally expand to integer constants) aren't
> > intended to move to the structure.
> 
> Whereas I presume that they _are_; consider that a goal here is to be
> able, at least in principle, to swap out the back end at runtime.

You have appropriate performance measures for this?  Needing e.g. always
to call a function to get the value of a target byte from a string when
almost all compilers actually have target bytes the same as host bytes
_seems_ inefficient but the question is: which target macros are used in
functions that show up significantly on a profile and what is the cost of
replacing those by structure elements?

-- 
Joseph S. Myers
jsm@polyomino.org.uk