vect: Use poly_int64 for prolog bound.

Since peeling and version for alignment for VLA modes was introduced
(r16-3065-geee51f9a4b6) we have been seeing a lot of test suite failures
like

  internal compiler error: in apply_scale, at profile-count.h:1187

This is because vect_gen_prolog_loop_niters sets the prolog bound to -1
in case align_in_elems is a non-constant poly_int.
bound - 1 is later used to scale the loop profile in scale_loop_profile
so we try to calculate with an assumed -2 iterations.

This patch changes bound_prolog to poly_int64, using a poly estimate for
frequency scaling but only records an iteration bound for the prolog if
the bound is a scalar.

	PR/tree-optimization 121523

gcc/ChangeLog:

	* tree-vect-loop-manip.cc (vect_gen_prolog_loop_niters):
	Change prolog bound to poly_int64.
	(vect_gen_scalar_loop_niters): Ditto.
	(vect_do_peeling): Use poly estimate for frequency scaling.

0 files changed, 0 insertions, 0 deletions