Re: [PATCH] Fix PR49715, (float)unsigned -> (float)signed

[Richard Henderson <rth at redhat dot com>]

On 07/21/2011 08:47 AM, Richard Guenther wrote:
> Hm, of course some targets define unsigned float expanders just do
> do the complicated stuff manually (which is why I didn't look
> at the conversion optabs).

Unfortunately, there's no way to tell optabs.c not to widen
conversions all the way into software-only fp modes.  This
has forced backends to replicate the fallback logic.

> I assume that if a target can do
> an unsigned -> float conversion it can also to a signed -> float
> conversion of the same source mode (probably a safe assumption?).

That's an assumption that's borne out in the md files.


r~