On Mon, Aug 18, 2025 at 9:25 PM Tamar Christina <tamar.christ...@arm.com>
wrote:
> commit g:fb59c5719c17a04ecfd58b5e566eccd6d2ac583a stops passing the scalar
> type
> (confusingly named vectype) to the costing hook when doing scalar costing.
>
> As a result, we could no longer distinguish between FPR and GPR scalar
> stmts.
> A later commit also removed STMT_VINFO_VECTYPE from stmt_info.
>
> This leaves the only remaining option to get the type of the original stmt
> in
> the stmt_info. This patch does this when we're performing scalar costing.
>
> Ideally I'd refactor this a bit because a lot of the hooks just need to
> know if
> it's FP or not, but this seems pointless with the ongoing costing churn.
> So for
> now this restores our costing.
>
> Bootstrapped Regtested on aarch64-none-linux-gnu,
> arm-none-linux-gnueabihf, x86_64-pc-linux-gnu
> -m32, -m64 and no issues.
>
> Ok for master?
>
Ok.
>
> Thanks,
> Tamar
>
> gcc/ChangeLog:
>
> PR target/121536
> * config/aarch64/aarch64.cc (aarch64_vector_costs::add_stmt_cost):
> Set
> vectype from type of lhs of gimple stmt.
>
> ---
> diff --git a/gcc/config/aarch64/aarch64.cc b/gcc/config/aarch64/aarch64.cc
> index
> f88b7c95f97e7099af00112405279afd05e045fd..2971224566f14da4a163a7d0aed72bdbb3ac40f9
> 100644
> --- a/gcc/config/aarch64/aarch64.cc
> +++ b/gcc/config/aarch64/aarch64.cc
> @@ -18045,6 +18045,17 @@ aarch64_vector_costs::add_stmt_cost (int count,
> vect_cost_for_stmt kind,
> tree vectype, int misalign,
> vect_cost_model_location where)
> {
> + /* If costing for scalar vectype will be null, look up the type
> through
+ stmt_info. */
>
Though I think this comment should be reworded slightly:
When costing for scalars, vectype will be NULL; so look up the type via
stmt_info's statement.
Thanks,
Andrew Pinski
> + if (m_costing_for_scalar && stmt_info)
> + {
> + gcc_assert (!vectype);
> + /* This won't work for e.g. gconds or other statements without a
> lhs,
> + but those only work on GPR anyway and this is the best we can
> do. */
> + if (tree lhs = gimple_get_lhs (STMT_VINFO_STMT (stmt_info)))
> + vectype = TREE_TYPE (lhs);
> + }
> +
> fractional_cost stmt_cost
> = aarch64_builtin_vectorization_cost (kind, vectype, misalign);
>
>
>
> --
>
