[PATCH][RFC] Fix PR63155

[Jeff Law]

On 03/09/15 07:01, Richard Biener wrote:
>
> Ok, like the following which adds a verify_ssa_coalescing () function
> (which could in theory be called from IL verification like verify_ssa)
> and calls it when ENABLE_CHECKING is defined.
>
> Bootstrap & regtest running on x86_64-unknown-linux-gnu.
>
> It didn't look appropriate for this stage to implement virtual operand
> verification.
>
> Ok this way?
>
> Thanks,
> Richard.
>
> 2015-03-06  Richard Biener  <rguenther@suse.de>
>
> 	PR middle-end/63155
> 	* tree-ssa-coalesce.h (verify_ssa_coalescing): Declare.
> 	* tree-ssa-coalesce.c (attempt_coalesce): Handle graph being NULL.
> 	(coalesce_partitions): Call verify_ssa_coalescing if ENABLE_CHECKING.
> 	Split out abnormal coalescing to ...
> 	(perform_abnormal_coalescing): ... this function.
> 	(coalesce_ssa_name): Perform abnormal coalescing without computing
> 	live/conflict.
> 	(verify_ssa_coalescing_worker): New function.
> 	(verify_ssa_coalescing): Likewise.
Looks good to me.

jeff