Re: [PATCH] Move most of *_double routines from fold-const.c to double-int.c

[Brooks Moses <brooks dot moses at codesourcery dot com>]

A couple of comments:

Richard Guenther wrote:
> This patch is the first one in a (hopefully, to be completed) series
> to consolidate computation routines on out double-int representation.
> It simply moves low-level routines to double-int.c where other low-level
> routines reside.

It seems rather of confusing to me that you're leaving the prototypes 
for these functions in tree.h rather than moving them to double-int.h 
where all the prototypes for double-int.c currently reside.  (Especially 
since, with my recent patch, tree.h directly includes double-int.h, so 
the result is the same for the compiler either way.)

> So, the immediate plan is to provide two lowlevel set of routines.  First
> what we basically have with the double_int routines, operating on the
> full width and not handling overflow in any way.  Second a set that
> operates with specified signedness and precision and tracks overflow
> with direction (-1 for overflow towards -INF, +1 for +INF, zero for no
> overflow).  I also plan to change most of the interfaces to pass
> double_ints instead of the split HOST_WIDE_INTs.

I wonder if some of the overflow handling that you're including for this 
could be used to clean up a bit of the overflow handling in the 
mpz-to-double-int conversion functions that I recently put in there. 
It's kind of messy as it stands now.

- Brooks