Re: [PATCH][ARM] PR target/69161: Don't ignore mode when matching comparison operator in cstore-like patterns

[Kyrill Tkachov <kyrylo dot tkachov at foss dot arm dot com>]

Ping
https://gcc.gnu.org/ml/gcc-patches/2016-01/msg02309.html

Thanks,
Kyrill

On 29/01/16 14:27, Kyrill Tkachov wrote:
> Hi all,
>
> Similar to aarch64, the arm port also suffers from PR target/69161 when combine
> tries to propagate a CCmode comparison into a vec_duplicate, creating invalid
> RTL that ICEs.
> Please refer to the PR and the aarch64 fix for more info.
> The fix for arm is very similar.
> We define a new predicate identical to arm_comparison_operator but
> make it not special so that it gets the normal mode checks.
> This prevents combine from matching an intermediate CCmode cstore
> (where it's doing an SImode SET of a CCmode source) which it then
> tries to propagate into a V4SImode vec_duplicate.
>
> The offending patterns are the cstore patterns, so this patch updates them
> to use the new predicate with mode checks. Both arm and thumb patterns
> are updated.
>
> There was no codegen difference observed on SPEC2006 for arm.
> Bootstrapped and tested on arm-none-linux-gnueabihf.
>
> Ok for trunk?
>
> Thanks,
> Kyrill
>
> 2016-01-29  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>
>
>     PR target/69161
>     * config/arm/predicates.md (arm_comparison_operator_mode):
>     New predicate.
>     * config/arm/arm.md (*mov_scc): Use arm_comparison_operator_mode
>     instead of arm_comparison_operator.
>     (*mov_negscc): Likewise.
>     (*mov_notscc): Likewise.
>     * config/arm/thumb2.md (*thumb2_mov_scc): Likewise.
>     (*thumb2_mov_negscc): Likewise.
>     (*thumb2_mov_negscc_strict_it): Likewise.
>     (*thumb2_mov_notscc): Likewise.
>     (*thumb2_mov_notscc_strict_it): Likewise.