On 22/11/2021 11:41, Richard Biener wrote:
>
>> On 18/11/2021 11:05, Richard Biener wrote:
>>> This is a good shout and made me think about something I hadn't before... I
>>> thought I could handle the vector forms later, but the problem is if I add
>>> support for the scalar, it will stop the vectorizer. It seems
>>> vectorizable_call expects all arguments to have the same type, which doesn't
>>> work with passing the integer type as an operand work around.
> We already special case some IFNs there (masked load/store and gather)
> to ignore some args, so that would just add to this set.
>
> Richard.
Hi,

Reworked it to add support of the new IFN to the vectorizer. Was 
initially trying to make vectorizable_call and 
vectorizable_internal_function handle IFNs with different inputs more 
generically, using the information we have in the <IFN>_direct structs 
regarding what operands to get the modes from. Unfortunately, that 
wasn't straightforward because of how vectorizable_call assumes operands 
have the same type and uses the type of the DEF_STMT_INFO of the 
non-constant operands (either output operand or non-constant inputs) to 
determine the type of constants. I assume there is some reason why we 
use the DEF_STMT_INFO and not always use get_vectype_for_scalar_type on 
the argument types. That is why I ended up with this sort of half-way 
mix of both, which still allows room to add more IFNs that don't take 
inputs of the same type, but require adding a bit of special casing 
similar to the IFN_FTRUNC_INT and masking ones.

Bootstrapped on aarch64-none-linux.

OK for trunk?

gcc/ChangeLog:

         * config/aarch64/aarch64.md (ftrunc<mode><frintnz_mode>2): New 
pattern.
         * config/aarch64/iterators.md (FRINTNZ): New iterator.
         (frintnz_mode): New int attribute.
         (VSFDF): Make iterator conditional.
         * internal-fn.def (FTRUNC_INT): New IFN.
         * internal-fn.c (ftrunc_int_direct): New define.
         (expand_ftrunc_int_optab_fn): New custom expander.
         (direct_ftrunc_int_optab_supported_p): New supported_p.
         * match.pd: Add to the existing TRUNC pattern match.
         * optabs.def (ftrunc_int): New entry.
         * stor-layout.h (element_precision): Moved from here...
         * tree.h (element_precision): ... to here.
         (element_type): New declaration.
         * tree.c (element_type): New function.
         (element_precision): Changed to use element_type.
         * tree-vect-stmts.c (vectorizable_internal_function): Add 
support for
         IFNs with different input types.
         (vectorizable_call): Teach to handle IFN_FTRUNC_INT.
         * doc/md.texi: New entry for ftrunc pattern name.
         * doc/sourcebuild.texi (aarch64_frintzx_ok): New target.

gcc/testsuite/ChangeLog:

         * gcc.target/aarch64/merge_trunc1.c: Adapted to skip if frintNz 
instruction available.
         * lib/target-supports.exp: Added arm_v8_5a_frintnzx_ok target.
         * gcc.target/aarch64/frintnz.c: New test.
         * gcc.target/aarch64/frintnz_vec.c: New test.