This patch makes two tweaks to vectorizable_conversion. The first
is to use "modifier" to distinguish between promotion, demotion,
and neither promotion nor demotion, rather than using a code for
some cases and "modifier" for others. The second is to take ncopies
into account for the promotion and demotion costs; previously we gave
multiple copies the same cost as a single copy.
Later patches test this, but it seemed worth splitting out.
2019-11-13 Richard Sandiford <richard.sandiford@arm.com>
gcc/
* tree-vect-stmts.c (vect_model_promotion_demotion_cost): Take the
number of ncopies as an additional argument.
(vectorizable_conversion): Update call accordingly. Use "modifier"
to check whether a conversion is between vectors with the same
numbers of units.
From-SVN: r278121
