Implement iterative dataflow in mod-ref

Implement iterative dataflow in mod-ref

cc1plus stats are now:

Alias oracle query stats:
  refs_may_alias_p: 62971744 disambiguations, 73160711 queries
  ref_maybe_used_by_call_p: 141176 disambiguations, 63867883 queries
  call_may_clobber_ref_p: 23573 disambiguations, 29322 queries
  nonoverlapping_component_refs_p: 0 disambiguations, 37720 queries
  nonoverlapping_refs_since_match_p: 19432 disambiguations, 55659 must overlaps, 75860 queries
  aliasing_component_refs_p: 54724 disambiguations, 753570 queries
  TBAA oracle: 24124230 disambiguations 56228428 queries
               16058141 are in alias set 0
               10338303 queries asked about the same object
               125 queries asked about the same alias set
               0 access volatile
               3919230 are dependent in the DAG
               1788399 are aritificially in conflict with void *

Modref stats:
  modref use: 10408 disambiguations, 46993 queries
  modref clobber: 1418549 disambiguations, 1951251 queries
  4898707 tbaa queries (2.510547 per modref query)
  396878 base compares (0.203397 per modref query)

PTA query stats:
  pt_solution_includes: 975364 disambiguations, 13604284 queries
  pt_solutions_intersect: 1026606 disambiguations, 13181198 queries

So compared to
https://gcc.gnu.org/pipermail/gcc-patches/2020-September/554692.html we get 25%
use disambiguations and 91% more clobber disambiguations.

Tramp3d is

Alias oracle query stats:
  refs_may_alias_p: 2056905 disambiguations, 2317461 queries
  ref_maybe_used_by_call_p: 7137 disambiguations, 2093762 queries
  call_may_clobber_ref_p: 234 disambiguations, 234 queries
  nonoverlapping_component_refs_p: 0 disambiguations, 4313 queries
  nonoverlapping_refs_since_match_p: 329 disambiguations, 10200 must overlaps, 10616 queries
  aliasing_component_refs_p: 858 disambiguations, 34600 queries
  TBAA oracle: 894996 disambiguations 1695991 queries
               138346 are in alias set 0
               470668 queries asked about the same object
               0 queries asked about the same alias set
               0 access volatile
               191666 are dependent in the DAG
               315 are aritificially in conflict with void *

Modref stats:
  modref use: 842 disambiguations, 2265 queries
  modref clobber: 14833 disambiguations, 28900 queries
  34884 tbaa queries (1.207059 per modref query)
  5041 base compares (0.174429 per modref query)

PTA query stats:
  pt_solution_includes: 313372 disambiguations, 525724 queries
  pt_solutions_intersect: 130374 disambiguations, 415138 queries

So about twice many use and 40% clobber disambiguations.

Bootstrapped/regtested x86_64-linux, I plan to commit it later today after
more testing.

2020-09-26  Jan Hubicka  <hubicka@ucw.cz>

	* ipa-inline-transform.c: Include ipa-modref-tree.h and ipa-modref.h.
	(inline_call): Call ipa_merge_modref_summary_after_inlining.
	* ipa-inline.c (ipa_inline): Do not free summaries.
	* ipa-modref.c (dump_records): Fix formating.
	(merge_call_side_effects): Break out from ...
	(analyze_call): ... here; record recursive calls.
	(analyze_stmt): Add new parameter RECURSIVE_CALLS.
	(analyze_function): Do iterative dataflow on recursive calls.
	(compute_parm_map): New function.
	(ipa_merge_modref_summary_after_inlining): New function.
	(collapse_loads): New function.
	(modref_propagate_in_scc): Break out from ...
	(pass_ipa_modref::execute): ... here; Do iterative dataflow.
	* ipa-modref.h (ipa_merge_modref_summary_after_inlining): Declare.