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Implement dominant contrib stability testing, which is stronger than …
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…attrib stability.
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Jason Evans committed May 15, 2024
1 parent 970608e commit dc41964
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123 changes: 83 additions & 40 deletions bootstrap/bin/hocc/ielr1.ml
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Original file line number Diff line number Diff line change
Expand Up @@ -377,48 +377,93 @@ let close_stable ~resolve io symbols prods lalr1_isocores lalr1_states adjs ~lal
split_unstable
end
end in
let gather_ipred_stability_deps_indexes ~resolve symbols prods ~lalr1_transit_attribs ~stable
~ipred_stability_deps ~unstable state_index ipred_split_unstable ipred_stability_deps_indexes
let is_dominant_contrib_unstable ~resolve symbols prods adjs ~lalr1_transit_attribs ~stable
Attrib.{conflict_state_index; symbol_index; contrib; _} state_index = begin
(* Compute whether the dominant contribution from the state (corresponding to `state_index`) to
* the isucc associated with the attrib parameter is unstable. *)
match not (Contrib.stable ~resolve symbols prods symbol_index contrib) with
| false -> begin
(* The contrib is split-stable, which means the state's dominant contribution is
* split-stable. However, the inverse does not necessarily hold, thus the meat of this
* function below. *)
false
end
| true -> begin
(* Resolution is unstable unless all the state's relevant incoming transits make the same
* dominant contribution. *)
let in_transits = Array.fold ~init:(Ordset.empty (module Transit))
~f:(fun in_transits ipred_state_index ->
let transit = Transit.init ~src:ipred_state_index ~dst:state_index in
match Ordmap.get transit lalr1_transit_attribs with
| None -> in_transits
| Some _ -> Ordset.insert transit in_transits
) (Adjs.ipreds_of_state_index state_index adjs) in
let in_transits_relevant =
filter_transits_relevant lalr1_transit_attribs in_transits ~conflict_state_index
symbol_index in
let is_resolution_unstable, _dominant_opt =
Ordset.fold_until ~init:(false, None)
~f:(fun (_is_resolution_unstable, dominant_opt)
(Transit.{src=ipred; _} as in_transit) ->
let Attrib.{contrib=in_contrib; _} =
Ordmap.get_hlt in_transit lalr1_transit_attribs
|> TransitAttribs.all
|> Attribs.get_hlt ~conflict_state_index symbol_index in
let resolution = match resolve with
| false -> in_contrib
| true -> Contrib.resolve symbols prods symbol_index in_contrib
in
let is_ipred_stable = Set.mem ipred stable in
let is_in_contrib_stable =
Contrib.stable ~resolve symbols prods symbol_index in_contrib in
let not_stable = not (is_ipred_stable || is_in_contrib_stable) in
let is_resolution_unstable, dominant_opt = match dominant_opt with
| None -> not_stable, Some resolution
| Some dominant as some_dominant ->
not_stable || not (Contrib.equal dominant resolution), some_dominant
in
(is_resolution_unstable, dominant_opt), is_resolution_unstable
) in_transits_relevant
in
is_resolution_unstable
end
end in
let gather_ipred_stability_deps_indexes ~resolve symbols prods adjs ~lalr1_transit_attribs ~stable
~unstable ipred_split_unstable ipred_stability_deps_indexes
Attrib.{conflict_state_index; symbol_index; _} in_transits_relevant = begin
(* If ipred is potentially split-unstable, the resolution of `contrib` must have stable
* resolution for all possible contrib subsets to recognize state as unconditionally
* split-stable. *)
let ipred_split_unstable, ipred_stability_deps_indexes = Ordset.fold_until
~init:(ipred_split_unstable, ipred_stability_deps_indexes)
~f:(fun (ipred_split_unstable, ipred_stability_deps_indexes)
(Transit.{src=ipred_state_index; _} as in_transit) ->
let is_ipred_stable = Set.mem ipred_state_index stable in
let is_ipred_unstable = Set.mem ipred_state_index unstable in
let is_resolution_unstable = match is_ipred_stable with
| true -> false
let ipred_split_unstable, ipred_stability_deps_indexes =
match is_ipred_stable with
| true -> ipred_split_unstable, ipred_stability_deps_indexes
| false -> begin
match Ordmap.get state_index ipred_stability_deps with
| Some ipred_stability_deps_indexes_prev ->
(* Use previously computed value. *)
Ordset.mem ipred_state_index ipred_stability_deps_indexes_prev
| None -> begin
let Attrib.{contrib; _} =
Ordmap.get_hlt in_transit lalr1_transit_attribs
|> TransitAttribs.all
|> Attribs.get_hlt ~conflict_state_index symbol_index
in
not (Contrib.stable ~resolve symbols prods symbol_index contrib)
let in_attrib =
Ordmap.get_hlt in_transit lalr1_transit_attribs
|> TransitAttribs.all
|> Attribs.get_hlt ~conflict_state_index symbol_index
in
let is_ipred_dominant_contrib_unstable =
is_dominant_contrib_unstable ~resolve symbols prods adjs ~lalr1_transit_attribs
~stable in_attrib ipred_state_index
in
let is_ipred_unstable = Set.mem ipred_state_index unstable in
match is_ipred_dominant_contrib_unstable, is_ipred_unstable with
| false, _ -> ipred_split_unstable, ipred_stability_deps_indexes
| true, false -> begin
(* Split-stability depends on the ipred being split-stable, and the ipred's
* split-stability is currently undetermined. Record the dependency on the ipred
* and requeue. *)
ipred_split_unstable,
Ordset.insert ipred_state_index ipred_stability_deps_indexes
end
| true, true -> begin
(* Split-stability depends on the ipred being split-stable, and the ipred is
* already known to be split-unstable. *)
true, ipred_stability_deps_indexes
end
end
in
let ipred_split_unstable, ipred_stability_deps_indexes =
match is_resolution_unstable, is_ipred_unstable with
| false, _ -> ipred_split_unstable, ipred_stability_deps_indexes
| true, false -> begin
(* Split-stability depends on the ipred being split-stable, and the ipred's
* split-stability is currently undetermined. Record the dependency on the ipred and
* requeue. *)
ipred_split_unstable, Ordset.insert ipred_state_index ipred_stability_deps_indexes
end
| true, true -> begin
(* Split-stability depends on the ipred being split-stable, and the ipred is already
* known to be split-unstable. *)
true, ipred_stability_deps_indexes
end
in
(ipred_split_unstable, ipred_stability_deps_indexes), ipred_split_unstable
Expand Down Expand Up @@ -491,15 +536,13 @@ let close_stable ~resolve io symbols prods lalr1_isocores lalr1_states adjs ~lal
end
in
let ipred_split_unstable, ipred_stability_deps_indexes =
gather_ipred_stability_deps_indexes ~resolve symbols prods
~lalr1_transit_attribs ~stable ~ipred_stability_deps ~unstable state_index
ipred_split_unstable ipred_stability_deps_indexes attrib
in_transits_relevant
gather_ipred_stability_deps_indexes ~resolve symbols prods adjs
~lalr1_transit_attribs ~stable ~unstable ipred_split_unstable
ipred_stability_deps_indexes attrib in_transits_relevant
in
let isucc_split_unstable, isucc_stability_deps_indexes =
gather_isucc_stability_deps_indexes ~stable ~unstable state_index
isucc_split_unstable isucc_stability_deps_indexes attrib
out_transits_relevant
isucc_split_unstable isucc_stability_deps_indexes attrib out_transits_relevant
in
(split_unstable, ipred_split_unstable, isucc_split_unstable,
ipred_stability_deps_indexes, isucc_stability_deps_indexes)
Expand Down
10 changes: 5 additions & 5 deletions bootstrap/test/hocc/Gawk.expected
View file
Original file line number Diff line number Diff line change
Expand Up @@ -8,12 +8,12 @@ hocc: Generating 322 LR(1) states
hocc: 410 conflicts in 50 states (0 ⊥, 410 shift-reduce, 0 reduce-reduce) (conflict resolution disabled)
hocc: Gathering IELR(1) conflict attributions..............................................
hocc: Closing IELR(1) conflict attributions (+.=propagate/quiesce)............+++.......++++++++++++......++..+................................................+++++++++++..+++.............++++........+++++++++..........................+................................+....................++++........................................+...+.........+............+++++++++......................+..++++++++++++++..+........+................++.+.+.+..
hocc: Closing IELR(1) state split-stability (^.=unstable/stable)^.....^^...^...................................................^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
hocc: 151 split-unstable states
hocc: Closing IELR(1) state split-stability (^.=unstable/stable)^..........^^.........^..........................................^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
hocc: 149 split-unstable states
hocc: LR(1) item set compatibility: ielr1
hocc: Generating LR(1) item set closures (+^.=add/split/merge)++++++++++++++++++++++++++++++++++++++++++++++++.^+.+^^^^^.^^.....^.++^.^.+^^^+.......++++^^^++++^^^^^^^+..^^^^^^^++++^[71/100]++++.+++++++++++++++++++++++++++++++++++++++++.++++++++.................++......................................................+++++++++...^...^^^..^..^^^...^^^^^.^^.^^^^^^..^^.+++++..^^^^^^...^^[138/200].....^+^^^^^^..^^+......^^^^^^^^^^^^^^..+.......^^^^^^......^^^^^^.^^^^++^.........+^^+^^^++++^^^^^^^.^^+^.^^^^^^^^+^^^^^^^^^+^++^^^^^^^^+^+[184/300]+^^^^^^^^+^^^^^^^^^+^.^^^^^.^^.....^.+^...............^^^^^^^^^^^^^+^^^^^^^+^^^^^^^+^^^^^^^+^^^^^^^+^^^^^^^+++++++++^^+++++[256/400].++++.++^^^+.^^.....++++++.+..........+^^^^+^++++^+^....................................................................................+^^^.^^.^^^^.+^++++^^^^^^^^^^^^^^^.^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^[292/500]^^^^^.^^^.........................................................+.+...++^^^+++.........^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^+^+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^[280/600]^.............^...................................................................................................................................................^^^^^^^^.^^^+^......................................................^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^+^^+++++^+++.+++^^...^..................................................................................................................+^^^^^^^^^^^^^^+.+++++++[284/700]+++++++^^^^^^+.++^.^++++.....^+^.^.^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^.......++..........^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^......^^[190/800]^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^+^^^^^^^^^^^^^^.++++^+++++.^^^^^^^^^^^^............................^++++++++++^++++^^^^^^^^.+^[195/900]^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^+.......^^^^^^^+++..................^^^^^^^^^^.^......+^^^^^^^^^^^^^^^^^^^^^^.^.............^^^^^^[203/1_000]^^^^.^^^^^^^^^^^.^^^^^^^^^^^.^^^^^^^^^^^.^^^^^^^^^^^^^^...............................................................................................................................+++^++++^.......^^^^^^^^^^^^^^^^^^^^.^...^^^^^^^^^^^^^^^^^.^^[202/1_100]^+^.^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^+^..+++.............................................................................................................................................^.^............+...............................^....^........^++^++.+++^^^^^^^^^^^^^^^^.^..............................................................................................................................^^^^+^^^^^^^^^^^^^^^^^^^[94/1_200]^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^....................................+^.....^^^.+++..+..^^^^^^^^^^^^^^^^^^^^^^^^^^^.....^^^^.^^^^.^^^^^^^^^^^^^^^^^^^^^[87/1_300]^^^^^^^^^^^^^^^^.....................+^^^++++^^^^^^^^^^^+^^^++^^^.^++^.^+^^+..+
hocc: Generating 1_354 LR(1) states
hocc: Generating LR(1) item set closures (+^.=add/split/merge)++++++++++++++++++++++++++++++++++++++++++++++++.^+.+^^^^^.^^.....^.++^.^.+^^^+.......++++^^^++++^^^^^^^+..^^^^^^^++++^[71/100]++++.+++++++++++++++++++++++++++++++++++++++++.++++++++.................++......................................................+++++++++...^...^^^..^..^^^...^^^^^.^^.^^^^^^..^^.+++++..^^^^^^...^^[138/200].....^+^^^^^^..^^+......^^^^^^^^^^^^^^..+.......^^^^^^......^^^^^^.^^^^++^.........+^^+^^^++++^^^^^^^.^^+^.^^^^^^^^+^^^^^^^^^+^++^^^^^^^^+^+[184/300]+^^^^^^^^+^^^^^^^^^+^.^^^^^.^^.....^.+^...............^^^^^^^^^^^^^+^^^^^^^+^^^^^^^+^^^^^^^+^^^^^^^+^^^^^^^+++++++++^^+++++[256/400].++++.++^^^+.^^.....++++++.+..........+^^^^+^++++^+^....................................................................................+^^^.^^.^^^^.+^++++^^^^^^^^^^^^^^^.^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^[292/500]^^^^^.^^^.........................................................+.+...++^^^+++.........^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^+^+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^[280/600]^.............^...................................................................................................................................................^^^^^^^^.^^^+^......................................................^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^+^^+++++^+++.+++^^...^..................................................................................................................+^^^^^^^^^^^^^^+.+++++++[284/700]+++++++^^^^^^+.++^.^++++.....^+^.^.^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^.......++..........^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^......^^[190/800]^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^+^^^^^^^^^^^^^^.++++^+++++.^^^^^^^^^^^^............................^++++++++++^++++^^^^^^^^.+^[195/900]^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^+.......^^^^^^^+++..................^^^^^^^^^^.^......+^^^^^^^^^^^^^^^^^^^^^^.^.............^^^^^^[203/1_000]^^^^.^^^^^^^^^^^.^^^^^^^^^^^.^^^^^^^^^^^.^^^^^^^^^^^^^^...............................................................................................................................+++^++++^.......^^^^^^^^^^^^^^^^^^^^.^...^^^^^^^^^^^^^^^^^.^^[202/1_100]^+^.^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^+^..+++.............................................................................................................................................^.^............+...............................^....^........^++^++.+++^^^^^^^^^^^^^^^^.^..............................................................................................................................^^^^+^^^^^^^^^^^^^^^^^^^[94/1_200]^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^....................................+^.....^^^.+++..+..^^^^^^^^^^^^^^^^^^^^^^^^^^^.....^^^^.^^^^.^^^^^^^^^^^^^^^^^^^^^[87/1_300]^^^^^^^^^^^^^^^^.....................+^^^++++^^^^^^^^^^^+^^^++^^^.^++^..^^.++.+
hocc: Generating 1_353 LR(1) states
hocc: 218 unresolvable conflicts in 104 states (0 ⊥, 218 shift-reduce, 0 reduce-reduce)
hocc: 164 unreachable states
hocc: 163 unreachable states
hocc: Reindexing 1_190 LR(1) states
hocc: Searching for unused precedences/tokens/non-terminals/productions

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