Re: Add value range support into memcpy/memset expansion

[Richard Biener <rguenther at suse dot de>]

On Fri, 15 Nov 2013, Jan Hubicka wrote:

> > Hi,
> > this patch makes it possible to access value range info from setmem/movstr that
> > I plan to use in i386 memcpy/memset expansion code.  It is all quite
> > straighforward except that I need to deal with cases where max size does not
> > fit in HOST_WIDE_INT where I use maximal value as a marker.  It is then
> > translated as NULL pointer to the expander that is bit inconsistent with other
> > places that use -1 as marker of unknown value.
> > 
> > I also think we lose some cases because of TER replacing out the SSA_NAME by
> > something else, but it seems to work in quite many cases. This can be probably
> > tracked incrementally by disabling TER here or finally getting away from
> > expanding calls via the generic route.
> > 
> > Bootstrapped/regtested x86_64-linux, OK?
> > 
> > Honza
> > 
> > 	* doc/md.texi (setmem, movstr): Update documentation.
> > 	* builtins.c (determine_block_size): New function.
> > 	(expand_builtin_memcpy): Use it and pass it to
> > 	emit_block_move_hints.
> > 	(expand_builtin_memset_args): Use it and pass it to
> > 	set_storage_via_setmem.
> > 	* expr.c (emit_block_move_via_movmem): Add min_size/max_size parameters;
> > 	update call to expander.
> > 	(emit_block_move_hints): Add min_size/max_size parameters.
> > 	(clear_storage_hints): Likewise.
> > 	(set_storage_via_setmem): Likewise.
> > 	(clear_storage): Update.
> > 	* expr.h (emit_block_move_hints, clear_storage_hints,
> > 	set_storage_via_setmem): Update prototype.
> 
> Ping...
> http://gcc.gnu.org/ml/gcc-patches/2013-09/msg02011.html

Ok - please make sure it still works after all the header re-org ;)

Thanks,
Richard.