On Sun, Jun 28, 2015 at 1:45 PM, Marc Glisse <marc.gli...@inria.fr> wrote:
> On Fri, 26 Jun 2015, Richard Biener wrote:
>
>>>>> OK. The reason I was being paranoid was that I couldn't see anywhere
>>>>> where we enforced that the vector condition in a VEC_COND had to have
>>>>> the same element width as the values being selected.
>>>>
>>>>
>>>>
>>>> We don't require that indeed.
>>>>
>>>>> tree-cfg.c
>>>>> only checks that rhs2 and rhs3 are compatible with the result.
>>>>> There doesn't seem to be any checking of rhs1 vs. the other types.
>>>>> So I wasn't sure whether anything stopped us from, e.g., comparing two
>>>>> V4HIs and using the result to select between two V4SIs.
>>>>
>>>>
>>>>
>>>> Nothing does (or should).
>>>
>>>
>>>
>>> The documentation patch you approved in
>>> https://gcc.gnu.org/ml/gcc-patches/2012-10/msg01109.html says something
>>> different. If it is really wrong, could you fix it?
>>
>>
>> Hmm, that simplifies things.
>
>
> On the other hand, vectors of bools could be (I haven't thought about it
> much) nice to have, especially for avx512 (and at least one other arch,
> maybe sparc).
>
>> It would be nice if these constraints would also be checked in the gimple
>> verifier...
>
>
> This passed bootstrap+testsuite on powerpc64le-unknown-linux-gnu.
Ok.
Thanks,
Richard.
> 2015-06-29 Marc Glisse <marc.gli...@inria.fr>
>
> * tree-cfg.c (verify_gimple_assign_ternary) <VEC_COND_EXPR>: Check
> the first argument.
>
> --
> Marc Glisse
> Index: gcc/tree-cfg.c
> ===================================================================
> --- gcc/tree-cfg.c (revision 225104)
> +++ gcc/tree-cfg.c (working copy)
> @@ -4001,8 +4001,22 @@
> }
> break;
>
> + case VEC_COND_EXPR:
> + if (!VECTOR_INTEGER_TYPE_P (rhs1_type)
> + || TYPE_SIGN (rhs1_type) != SIGNED
> + || TYPE_SIZE (rhs1_type) != TYPE_SIZE (lhs_type)
> + || TYPE_VECTOR_SUBPARTS (rhs1_type)
> + != TYPE_VECTOR_SUBPARTS (lhs_type))
> + {
> + error ("the first argument of a VEC_COND_EXPR must be of a signed
> "
> + "integral vector type of the same size and number of "
> + "elements as the result");
> + debug_generic_expr (lhs_type);
> + debug_generic_expr (rhs1_type);
> + return true;
> + }
> + /* Fallthrough. */
> case COND_EXPR:
> - case VEC_COND_EXPR:
> if (!useless_type_conversion_p (lhs_type, rhs2_type)
> || !useless_type_conversion_p (lhs_type, rhs3_type))
> {
>
