[PATCH] Fix CSE CLZ/CTZ handling (PR rtl-optimization/85376, variant)

[Richard Biener]

On April 13, 2018 9:33:31 PM GMT+02:00, Eric Botcazou <ebotcazou@adacore.com> wrote:
>> 2018-04-13  Jakub Jelinek  <jakub@redhat.com>
>> 
>> 	PR rtl-optimization/85376
>> 	* simplify-rtx.c (simplify_const_unary_operation): For CLZ and CTZ
>and
>> 	zero op0, if C?Z_DEFINED_VALUE_AT_ZERO is false, return NULL_RTX
>> 	instead of a specific value.
>> 
>> 	* gcc.dg/pr85376.c: New test.
>
>My preference would be for this one.

Likewise. 

Richard.