Re: Handle splitting basic blocks in lower-subreg.c

[Ian Lance Taylor <iant at google dot com>]

"Steven Bosscher" <stevenb.gcc@gmail.com> writes:

> This is my first attempt at removing find_many_sub_basic_blocks out of
> lower-subreg.c.  Ian, should I expect other cases, or is just handling
> loads to multi-word pseudos the only case that can cause new control
> flow insns to appear?

That should be the only case.  If other cases somehow appear, I don't
have any problem with blocking them in find_decomposable_subregs.

> 	* lower-subreg.c: Include except.h.
> 	(decompose_multiword_subregs): Verify that the only control flow
> 	insns we can split are loads to multi-words pseudos.
> 	Handle breaking such blocks after splitting, instead of calling
> 	find_many_sub_basic_blocks.

This is OK, except:

> +#ifdef ENABLE_CHECKING
> +      verify_flow_info ();
> +#endif

you don't need that, because the pass structs have TODO_verify_flow.
Or, if you want that anyhow, take out the TODO_verify_flow.

Thanks for cleaning up after me.

Ian