remembering comparison modes

[Bernd Schmidt]

On Wed, 24 Jan 2001, Michael Meissner wrote:
> >
> > Er, strict_low_part is a wrapper only.  It never has a mode.
> > The mode is taken from the subreg that is its argument.
>
> On the other hand, it makes looking up what type of SET (ie, QI/HI/etc.)
> you are dealing with if you can't just check the mode of SET_DEST (you can't
> check the mode of SET_SRC because that might be a CONST_INT).  I'm pretty sure
> there are lots of places in the compiler that blindly do it.  Doing a simple
> minded grep for GET_MODE.*SET_DEST, I find:
>
> 	combine.c	cse.c		function.c	gcse.c
> 	integrate.c	jump.c		loop.c		recog.c
> 	regclass.c	reload1.c	rtlanal.c	ssa.c
>
> I haven't checked every usage, but it wouldn't surprise me if either their are
> places that blindly assume the destination has the correct mode, or don't
> optimize strict_low_part constructs as well.

Maybe I should get back to my abandoned attempt to get rid of strict_low_part...


Bernd