Re: [PATCH, vec-tails 02/10] Extend _loop_vec_info structure with epilogue related fields

[Jeff Law <law at redhat dot com>]

On 05/19/2016 01:38 PM, Ilya Enkovich wrote:
> Hi,
>
> This patch adds new fields to _loop_vec_info structure to support loop
> epilogue vectorization.
>
> Thanks,
> Ilya
> --
> gcc/
>
> 2016-05-19  Ilya Enkovich  <ilya.enkovich@intel.com>
>
> 	* tree-vectorizer.h (struct _loop_vec_info): Add new fields
> 	can_be_masked, required_masks, mask_epilogue, combine_epilogue,
> 	need_masking, orig_loop_info.
> 	(LOOP_VINFO_CAN_BE_MASKED): New.
> 	(LOOP_VINFO_REQUIRED_MASKS): New.
> 	(LOOP_VINFO_COMBINE_EPILOGUE): New.
> 	(LOOP_VINFO_MASK_EPILOGUE): New.
> 	(LOOP_VINFO_NEED_MASKING): New.
> 	(LOOP_VINFO_ORIG_LOOP_INFO): New.
> 	(LOOP_VINFO_EPILOGUE_P): New.
> 	(LOOP_VINFO_ORIG_MASK_EPILOGUE): New.
> 	(LOOP_VINFO_ORIG_VECT_FACTOR): New.
> 	* tree-vect-loop.c (new_loop_vec_info): Initialize new
> 	_loop_vec_info fields.
I don't see anything here that is inherently wrong/bad here; I think 
this would be fine once the whole set is approved.   I also think if you 
find that you need additional similar kinds of fields, that would be OK 
as well.

The one question I would ask -- do we ever need to copy VINFO data from 
one loop to a duplicate, and if so, ISTM that the code to copy that data 
would be a part of this patch.

jeff