[PATCH] Make bitmap_set_bit and bitmap_clear_bit return if the bit changed

[Ian Lance Taylor]

Richard Guenther <rguenther@suse.de> writes:

> This lets us simplify some code and apply the do-not-write if nothing
> will change optimization in the general code.
>
> Bootstrap & regtest running, any objections to that change?

Looks good to me.

Ian

> 2008-07-01  Richard Guenther  <rguenther@suse.de>
>
> 	* bitmap.h (bitmap_set_bit): Return bool.
> 	(bitmap_clear_bit): Likewise.
> 	* bitmap.c (bitmap_set_bit): Return if the bit changed.  Only
> 	write to the bitmap if it would.
> 	(bitmap_clear_bit): Likewise.
> 	* tree-ssa-structalias.c (add_implicit_graph_edge): Use
> 	bitmap_set_bit return value.
> 	(add_pred_graph_edge): Likewise.
> 	(add_graph_edge): Likewise.
> 	(do_sd_constraint): Likewise.
> 	(do_ds_constraint): Likewise.