tree-optimization/102847 - properly cost VMAT_INVARIANT loads
Commit Message
The following adds proper costing of VMAT_INVARIANT loads, avoiding
to ask the target about the cost of an unsupported vector load cost
which we won't emit anyway.
Bootstrapped and tested on x86_64-unknown-linux-gnu, pushed.
2021-10-21 Richard Biener <rguenther@suse.de>
PR tree-optimization/102847
* tree-vect-stmts.c (vect_model_load_cost): Explicitely
handle VMAT_INVARIANT as a splat in the prologue.
---
gcc/tree-vect-stmts.c | 7 +++++++
1 file changed, 7 insertions(+)
@@ -1191,6 +1191,13 @@ vect_model_load_cost (vec_info *vinfo,
ncopies * assumed_nunits,
scalar_load, stmt_info, 0, vect_body);
}
+ else if (memory_access_type == VMAT_INVARIANT)
+ {
+ /* Invariant loads will ideally be hoisted and splat to a vector. */
+ prologue_cost += record_stmt_cost (cost_vec, 1,
+ scalar_to_vec, stmt_info, 0,
+ vect_prologue);
+ }
else
vect_get_load_cost (vinfo, stmt_info, ncopies,
alignment_support_scheme, misalignment, first_stmt_p,