Re: [PATCH] Start to Fix PR 28436: accessing an element via a "pointer" on a vector does not cause vec_extract to be used

[Roger Sayle <roger at eyesopen dot com>]

On Mon, 20 Nov 2006 Andrew_Pinski@PlayStation.Sony.Com wrote:
>
>         * tree.h (DECL_COMPLEX_GIMPLE_REG_P): Rename to ...
>         (DECL_GIMPLE_REG_P): This.
>         * fold-const.c (fold_indirect_ref_1): Fold *(foo *)&vectorfoo into
>         using BIT_FIELD_REF.
>         * omp-low.c (omp_copy_decl_2): Use the renamed DECL_GIMPLE_REG_P.
>         * tree-gimple.c (is_gimple_reg): Use the renamed DECL_GIMPLE_REG_P
>         and check for VECTOR_TYPE.
>         * expr.c (get_inner_reference): Set the mode for BIT_FIELD_REF
> with
>         vector types.
>         * tree-flow-inline.h (var_can_have_subvars): Use the renamed
>         DECL_GIMPLE_REG_P.
>         * gimplify.c (internal_get_tmp_var): Use the renamed
> DECL_GIMPLE_REG_P
>         and check for VECTOR_TYPE.
>         (gimplify_bind_expr): Likewise.
>         (gimplify_function_tree): Likewise.
>         * expmed.c: Include target.h.
>         (extract_bit_field): For vector mode, try find a better mode
> first.
>         If that fails use gen_lowpart (for vectors only).
>         * tree-dfa.c (make_rename_temp): Use the renamed DECL_GIMPLE_REG_P
>         and check for VECTOR_TYPE.
>         * tree-ssa-pre.c (create_expressions_by_pieces): Likewise.
>         (insert_into_preds_of_block): Likewise.
>         (insert_fake_stores): Create gimple register store_tmps for
>         vector types.
>         * tree-sra.c (sra_elt): New field, is_vector_lhs.
>         (sra_walk_expr <case BIT_FIELD_REF>): For vector types that
>         are the left hand side, set the element's is_vector_lhs to true.
>         (instantiate_element): For vector types which were on the left
>         hand size, set DECL_GIMPLE_REG_P to false.
>         * tree-nested.c (create_tmp_var_for): Use the renamed
> DECL_GIMPLE_REG_P.
>         * tree-inline.c (declare_return_variable):  Use the renamed
> DECL_GIMPLE_REG_P
>         and check for VECTOR_TYPE.
>         (copy_decl_to_var):  Use the renamed DECL_GIMPLE_REG_P.
>         (copy_result_decl_to_var): Likewise.
>         * tree-vect-transform.c (vect_get_new_vect_var): For vector types,
> create a
>         gimple register variable.
>         * Makefile.in (expmed.o): Update dependencies.
>
> testsuite/ChangeLog:
>         * gcc.c-torture/compile/vector-1.c: New test.
>         * gcc.c-torture/compile/vector-2.c: New test.
>         * gcc.c-torture/compile/vector-3.c: New test.

This is OK for mainline.  I agree that this patch should probably have
been divided into smaller pieces to simplify review, however the
fold-const.c change is fine, and the majority of the DECL_GIMPLE_REG_P
clean-up is mechanical and obvious.  Hopefully, the SRA folks are happy
with your bug-fix of using an new is_vector_lhs field.  If not I'm sure
they'll let us know.

Roger
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