Re: [Scalar masks 2/x] Use bool masks in if-conversion

[Jeff Law <law at redhat dot com>]

On 08/17/2015 10:25 AM, Ilya Enkovich wrote:
> Hi,
>
> This patch intoriduces a new vectorizer hook use_scalar_mask_p which affects code generated by if-conversion pass (and affects patterns in later patches).
>
> Thanks,
> Ilya
> --
> 2015-08-17  Ilya Enkovich  <enkovich.gnu@gmail.com>
>
> 	* doc/tm.texi (TARGET_VECTORIZE_USE_SCALAR_MASK_P): New.
> 	* doc/tm.texi.in: Regenerated.
> 	* target.def (use_scalar_mask_p): New.
> 	* tree-if-conv.c: Include target.h.
> 	(predicate_mem_writes): Don't convert boolean predicates into
> 	integer when scalar masks are used.
Presumably this is how you prevent the generation of scalar masks rather 
than boolean masks on targets which don't have the former?

I hate to ask, but how painful would it be to go from a boolean to 
integer masks later such as during expansion?  Or vice-versa.

WIthout a deep knowledge of the entire patchkit, it feels like we're 
introducing target stuff in a place where we don't want it and that we'd 
be better served with a canonical representation through gimple, then 
dropping into something more target specific during gimple->rtl expansion.


Jeff