SVE needs a way of broadcasting a scalar to a variable-length vector.
This patch adds VEC_DUPLICATE_EXPR for when CONSTRUCTOR would be used
for fixed-length vectors; this is the tree equivalent of the existing
rtl code VEC_DUPLICATE.
The patch also adds a vec_duplicate_optab to go with VEC_DUPLICATE_EXPR.
2017-12-16 Richard Sandiford <richard.sandiford@linaro.org>
Alan Hayward <alan.hawyard@arm.com>
David Sherwood <david.sherwood@arm.com>
gcc/
* doc/generic.texi (VEC_DUPLICATE_EXPR): Document.
(VEC_COND_EXPR): Add missing @tindex.
* doc/md.texi (vec_duplicate@var{m}): Document.
* tree.def (VEC_DUPLICATE_EXPR): New tree codes.
* tree.c (build_vector_from_val): Add stubbed-out handling of
variable-length vectors, using VEC_DUPLICATE_EXPR.
(uniform_vector_p): Handle VEC_DUPLICATE_EXPR.
* cfgexpand.c (expand_debug_expr): Likewise.
* tree-cfg.c (verify_gimple_assign_unary): Likewise.
* tree-inline.c (estimate_operator_cost): Likewise.
* tree-pretty-print.c (dump_generic_node): Likewise.
* tree-vect-generic.c (ssa_uniform_vector_p): Likewise.
* fold-const.c (const_unop): Fold VEC_DUPLICATE_EXPRs of a constant.
(test_vec_duplicate_folding): New function.
(fold_const_c_tests): Call it.
* optabs.def (vec_duplicate_optab): New optab.
* optabs-tree.c (optab_for_tree_code): Handle VEC_DUPLICATE_EXPR.
* optabs.h (expand_vector_broadcast): Declare.
* optabs.c (expand_vector_broadcast): Make non-static. Try using
vec_duplicate_optab.
* expr.c (store_constructor): Try using vec_duplicate_optab for
uniform vectors.
(expand_expr_real_2): Handle VEC_DUPLICATE_EXPR.
Co-Authored-By: Alan Hayward <alan.hayward@arm.com>
Co-Authored-By: David Sherwood <david.sherwood@arm.com>
From-SVN: r255740
