mercurylang/mercury
1
0
Fork 0
mirror of https://github.com/Mercury-Language/mercury.git synced 2025-12-15 22:03:26 +00:00
Code Issues Projects Releases Wiki Activity
Files
1cfbebfe8c90e9095720b2e97c532efb51f44474
mercury/browser/declarative_analyser.m
Zoltan Somogyi b56885be93 Fix a bug that caused bootchecks with --optimize-constructor-last-call to fail. 
Estimated hours taken: 12
Branches: main

Fix a bug that caused bootchecks with --optimize-constructor-last-call to fail.

The problem was not in lco.m, but in follow_code.m. In some cases,
(specifically, the LCMC version of insert_2 in sparse_bitset.m),
follow_code.m moved an impure goal (store_at_ref) into the arms of an
if-then-else without marking those arms, or the if-then-else, as impure.
The next pass, simplify, then deleted the entire if-then-else, since it
had no outputs. (The store_at_ref that originally appeared after the
if-then-else was the only consumer of its only output.)

The fix is to get follow_code.m to make branched control structures such as
if-then-elses, as well as their arms, semipure or impure if a goal being moved
into them is semipure or impure, or if they came from an semipure or impure
conjunction.

Improve the optimization of the LCMC version of sparse_bitset.insert_2, which
had a foreign_proc invocation of bits_per_int in it: replace such invocations
with a unification of the bits_per_int constant if not cross compiling.

Add a new option, --optimize-constructor-last-call-null. When set, LCMC will
assign NULLs to the fields not yet filled in, to avoid any junk happens to be
there from being followed by the garbage collector's mark phase.

This diff also makes several other changes that helped me to track down
the bug above.

compiler/follow_code.m:
	Make the fix described above.

	Delete all the provisions for --prev-code; it won't be implemented.

	Don't export a predicate that is not now used anywhere else.

compiler/simplify.m:
	Make the optimization described above.

compiler/lco.m:
	Make sure that the LCMC specialized procedure is a predicate, not a
	function: having a function with the mode LCMC_insert_2(in, in) = in
	looks wrong.

	To avoid name collisions when a function and a predicate with the same
	name and arity have LCMC applied to them, include the predicate vs
	function status of the original procedure included in the name of the
	new procedure.

	Update the sym_name of calls to LCMC variants, not just the pred_id,
	because without that, the HLDS dump looks misleading.

compiler/pred_table.m:
	Don't have optimizations like LCMC insert new predicates at the front
	of the list of predicates. Maintain the list of predicates in the
	module as a two part list, to allow efficient addition of new pred_ids
	at the (logical) end without using O(N^2) algorithms. Having predicates
	in chronological order makes it easier to look at HLDS dumps and
	.c files.

compiler/hlds_module.m:
	Make module_info_predids return a module_info that is physically
	updated though logically unchanged.

compiler/options.m:
	Add --optimize-constructor-last-call-null.

	Make the options --dump-hlds-pred-id, --debug-opt-pred-id and
	--debug-opt-pred-name into accumulating options, to allow the user
	to specify more than one predicate to be dumped (e.g. insert_2 and
	its LCMC variant).

	Delete --prev-code.

doc/user_guide.texi:
	Document the changes in options.m.

compiler/code_info.m:
	Record the value of --optimize-constructor-last-call-null in the
	code_info, to avoid lookup at every cell construction.

compiler/unify_gen.m:
compiler/var_locn.m:
	When deciding whether a cell can be static or not, make sure that
	we never make static a cell that has some fields initialized with
	dummy zeros, to be filled in for real later.

compiler/hlds_out.m:
	For goals that are semipure or impure, note this fact. This info was
	lost when I changed the representation of impurity from markers to a
	field.

mdbcomp/prim_data.m:
	Rename some ambiguous function symbols.

compiler/intermod.m:
compiler/trans_opt.m:
	Rename the main predicates (and some function symbols) of these modules
	to avoid ambiguity and to make them more expressive.

compiler/llds.m:
	Don't print line numbers for foreign_code fragments if the user has
	specified --no-line-numbers.

compiler/make.dependencies.m:
compiler/mercury_to_mercury.m:
compiler/recompilation.usage.m:
	Don't use io.write to write out information to files we may need to
	parse again, because this is vulnerable to changes to the names of
	function symbols (e.g. the one to mdbcomp/prim_data.m).

	The compiler still contains some uses of io.write, but they are
	for debugging. I added an item to the todo list of the one exception,
	ilasm.m.

compiler/recompilation.m:
	Rename a misleading function symbol name.

compiler/parse_tree.m:
	Don't import recompilation.m here. It is not needed (all the components
	of parse_tree that need recompilation.m already import it themselves),
	and deleting the import avoids recompiling almost everything when
	recompilation.m changes.

compiler/*.m:
	Conform to the changes above.

compiler/*.m:
browser/*.m:
slice/*.m:
	Conform to the change to mdbcomp.

library/sparse_bitset.m:
	Use some better variable names.
2007-01-19 07:05:06 +00:00

1378 lines
56 KiB
Mathematica
Raw Blame History

%-----------------------------------------------------------------------------%
% vim: ft=mercury ts=4 sw=4 et
%-----------------------------------------------------------------------------%
% Copyright (C) 1999-2007 The University of Melbourne.
% This file may only be copied under the terms of the GNU Library General
% Public License - see the file COPYING.LIB in the Mercury distribution.
%-----------------------------------------------------------------------------%
%
% File: declarative_analyser.m
% Authors: Mark Brown, Ian MacLarty
%
% This module implements some analysis algorithms that search for bugs in
% Evaluation Dependency Trees (EDTs). The search algorithms use information
% provided by the search_space data type which acts as a layer on top of the
% EDT, storing information relevant to the bug search. Throughout this module
% the type variables T and S refer to the types of nodes in the EDT and the
% store of EDT nodes respectively.
%
%-----------------------------------------------------------------------------%
%-----------------------------------------------------------------------------%
:- module mdb.declarative_analyser.
:- interface.
:- import_module mdb.declarative_debugger.
:- import_module mdb.declarative_edt.
:- import_module mdb.declarative_oracle.
:- import_module mdb.declarative_user.
:- import_module io.
:- import_module maybe.
%-----------------------------------------------------------------------------%
:- type analyser_response(T)
---> analyser_response_no_suspects
% There are no suspects left, and no incorrect
% nodes have been found.
; analyser_response_bug_found(decl_bug, decl_evidence(T))
% A suspect who is guilty, along with the evidence
% against the suspect.
; analyser_response_oracle_question(decl_question(T))
% The analyser desires an answer to the question.
; analyser_response_require_explicit_subtree(T)
% The analyser requires the given implicit sub-tree
% to be made explicit.
; analyser_response_require_explicit_supertree(T)
% The analyser requires an explicit tree above the
% root of an existing explicit tree.
; analyser_response_revise(decl_question(T)).
% The analyser would like the oracle to re-ask the user
% this question and then for analysis to continue.
:- func reason_to_string(reason_for_question) = string.
:- type analyser_state(T).
:- type search_mode.
:- func divide_and_query_search_mode = search_mode.
:- func suspicion_divide_and_query_search_mode = search_mode.
:- func top_down_search_mode = search_mode.
:- pred analyser_state_init(analyser_state(T)::out) is det.
% Resets the state of the analyser.
%
:- pred reset_analyser(analyser_state(T)::in, analyser_state(T)::out) is det.
% Make the given search mode the fallback search mode
% and the current search mode for the analyser.
%
:- pred set_fallback_search_mode(S::in, search_mode::in,
analyser_state(T)::in, analyser_state(T)::out)
is det <= mercury_edt(S, T).
:- type analysis_type(T)
---> new_tree(T)
% Use the given tree to do analysis. The tree will be
% a new explicitly generated portion of the annotated
% trace. start_or_resume_analysis should be called
% with this type of analysis when a new declarative
% debugging session has been started or a requested
% subtree or supertree has been generated.
; resume_previous.
% Continue the previous analysis. This will happen
% when the user suspends a declarative debugging
% session with a `pd' or `abort' command and now wants
% to continue the suspended session.
% Perform analysis on the given EDT, which may be a new tree
% to diagnose, or a sub-tree that was required to be made explicit.
%
:- pred start_or_resume_analysis(S::in, oracle_state::in, analysis_type(T)::in,
analyser_response(T)::out, analyser_state(T)::in,
analyser_state(T)::out) is det <= mercury_edt(S, T).
% Return a response which will cause the last question to be re-asked.
%
:- pred reask_last_question(S::in, analyser_state(T)::in,
analyser_response(T)::out) is semidet <= mercury_edt(S, T).
% Continue analysis after the oracle has responded with an answer.
%
:- pred continue_analysis(S::in, oracle_state::in, decl_answer(T)::in,
analyser_response(T)::out, analyser_state(T)::in,
analyser_state(T)::out) is det <= mercury_edt(S, T).
% Change the current search mode of the analyser and return the
% next question using the new search mode.
%
:- pred change_search_mode(S::in, oracle_state::in, user_search_mode::in,
analyser_state(T)::in, analyser_state(T)::out,
analyser_response(T)::out) is det <= mercury_edt(S, T).
% Display information about the current question and the state
% of the search to the supplied output stream.
%
:- pred show_info(S::in, io.output_stream::in, analyser_state(T)::in,
io::di, io::uo) is det <= mercury_edt(S, T).
% Revise the current analysis. This is done when a bug determined
% by the analyser has been overruled by the oracle.
%
:- pred revise_analysis(S::in, analyser_response(T)::out,
analyser_state(T)::in, analyser_state(T)::out) is det <= mercury_edt(S, T).
% Return information within the analyser state that is intended for
% debugging the declarative debugger itself.
%
:- pred debug_analyser_state(analyser_state(T)::in,
maybe(subterm_origin(T))::out) is det.
%-----------------------------------------------------------------------------%
%-----------------------------------------------------------------------------%
:- implementation.
:- import_module mdb.browser_info.
:- import_module mdb.declarative_edt.
:- import_module mdb.declarative_execution.
:- import_module mdbcomp.prim_data.
:- import_module mdbcomp.program_representation.
:- import_module mdbcomp.rtti_access.
:- import_module array.
:- import_module bool.
:- import_module exception.
:- import_module float.
:- import_module int.
:- import_module list.
:- import_module map.
:- import_module math.
:- import_module pair.
:- import_module string.
:- import_module unit.
%-----------------------------------------------------------------------------%
% Describes what search strategy is being used by the analyser and the
% state of the search.
%
:- type search_mode
---> analyser_top_down
% Look for the first unknown suspect in a top-down fashion,
% starting at the root. If no unknown suspects are found then
% choose a skipped suspect to requery.
; analyser_follow_subterm_end(
% Follow the subterm all the way to where it's bound or
% until it can't be followed any further (for example
% when there is a call to a module with no tracing),
% and ask a question about the nearest unknown suspect
% on the subterm dependency chain. Then proceed to do
% a binary search between this node and the root of the
% search space (the binary search will only come into
% effect if the oracle asserts the suspect is correct
% or inadmissible).
suspect_id,
arg_pos,
term_path,
% The above 3 args give the position the sub-term tracking
% algorithm has got up to if it needs to stop to wait for
% an explicit sub/super-tree to be generated.
maybe(suspect_id),
% The last suspect on the dependency chain whose status was
% unknown. Initially this is no, but as the sub-term is tracked
% to where it was initially bound (which could be above or
% below the node where it was marked incorrect), the most
% recent node through which the sub-term was tracked that
% has a status of `unknown' is stored in this field. This is
% then used as the next question if the node that bound
% the sub-term is trusted or in an excluded part of the search
% tree.
how_track_subterm
% This field specifies the algorithm to use when tracking
% the subterm.
)
; analyser_binary(
% Perform a binary search on a path in the search space
% between a suspect and an ancestor of the suspect.
% The path is represented as an array (the 1st argument)
% with the deeper suspect at the end of the array and its
% ancestor at the beginning. The range field gives the
% inclusive subrange of the array to search. last_tested
% is the index into the array of the last suspect about which
% a question was asked.
suspects :: array(suspect_id),
range :: pair(int, int),
last_tested :: int
)
; analyser_divide_and_query(weighting_heuristic).
% Divide and query using the given weighting heuristic.
divide_and_query_search_mode = analyser_divide_and_query(number_of_events).
suspicion_divide_and_query_search_mode = analyser_divide_and_query(suspicion).
top_down_search_mode = analyser_top_down.
% Each search algorithm should respond with either a question
% or a request for an explicit subtree to be generated for a suspect
% which is the root of an implicit subtree.
%
:- type search_response
---> search_response_question(suspect_id, reason_for_question)
; search_response_require_explicit_subtree(suspect_id)
; search_response_require_explicit_supertree
; search_response_no_suspects
; search_response_found_bug(suspect_id, list(suspect_id),
list(suspect_id)).
% The reason the declarative debugger asked a question.
%
:- type reason_for_question
---> ques_reason_start
% The first question.
; ques_reason_top_down
; ques_reason_binding_node(
binding_prim_op :: primitive_op_type,
binding_filename :: string,
binding_line_no :: int,
maybe_atom_path :: maybe(term_path),
% The path of the subterm in the
% binding node, if it appears in the
% binding node's atom.
binding_proc :: proc_label,
binding_node_eliminated :: bool
)
; ques_reason_subterm_no_proc_rep
% No proc rep when tracking subterm.
; ques_reason_binding_node_eliminated
; ques_reason_binary(
binary_reason_bottom :: int,
binary_reason_top :: int,
binary_reason_split :: int
)
; ques_reason_divide_and_query(
dq_weighting :: weighting_heuristic,
dq_old_weight :: int,
% The weight of the search space before
% the question was asked.
dq_chosen_subtree_weight :: int
% The weight the searchspace will be
% if the user answers `no' to the
% current question.
)
; ques_reason_skipped
; ques_reason_revise.
% The analyser state records all of the information that needs
% to be remembered across multiple invocations of the analyser.
%
:- type analyser_state(T)
---> analyser(
% Information about the EDT nodes relevant to
% the bug search.
search_space :: search_space(T),
% This is set to yes when an explicit tree needs to be
% generated. The maybe argument says what type of explicit
% tree needs to be generated.
require_explicit :: maybe(explicit_tree_type),
% The method currently being employed to search
% the search space for questions for the
% oracle.
search_mode :: search_mode,
% The search mode to use by default.
% Only non-parametrized search modes should
% be used as the fallback search mode.
fallback_search_mode :: search_mode,
% Everytime a search finds a suspect to ask the oracle
% about it is put in this field before asking the oracle,
% so the analyser knows how to modify the search space when
% it gets an answer.
last_search_question :: maybe(suspect_and_reason),
% This field is present only to make it easier
% to debug the dependency tracking algorithm;
% if bound to yes, it records the result of
% the invocation of that algorithm on the last
% analysis step.
debug_origin :: maybe(subterm_origin(T))
).
:- type suspect_and_reason
---> suspect_and_reason(suspect_id, reason_for_question).
:- type explicit_tree_type
---> explicit_subtree(suspect_id)
% Generate an explicit subtree for the implicit root
% referenced by the suspect_id.
; explicit_supertree.
% Generate a new explicit tree above the current
% explicit tree.
analyser_state_init(Analyser) :-
Analyser = analyser(empty_search_space, no,
analyser_top_down, analyser_top_down, no, no).
reset_analyser(!Analyser) :-
FallBack = !.Analyser ^ fallback_search_mode,
!:Analyser = analyser(empty_search_space, no, FallBack, FallBack, no, no).
set_fallback_search_mode(Store, FallBackSearchMode, !Analyser) :-
!:Analyser = !.Analyser ^ fallback_search_mode := FallBackSearchMode,
!:Analyser = !.Analyser ^ search_mode := FallBackSearchMode,
!:Analyser = !.Analyser ^ last_search_question := no,
( FallBackSearchMode = analyser_divide_and_query(Weighting) ->
SearchSpace0 = !.Analyser ^ search_space,
update_weighting_heuristic(Store, Weighting, SearchSpace0,
SearchSpace),
!:Analyser = !.Analyser ^ search_space := SearchSpace
;
true
).
debug_analyser_state(Analyser, Analyser ^ debug_origin).
start_or_resume_analysis(Store, Oracle, AnalysisType, Response, !Analyser) :-
(
AnalysisType = new_tree(Node),
MaybeRequireExplicit = !.Analyser ^ require_explicit,
(
MaybeRequireExplicit = yes(TreeType),
SearchSpace0 = !.Analyser ^ search_space,
(
TreeType = explicit_supertree,
incorporate_explicit_supertree(Store, Oracle, Node,
SearchSpace0, SearchSpace)
;
TreeType = explicit_subtree(SuspectId),
incorporate_explicit_subtree(SuspectId, Node,
SearchSpace0, SearchSpace)
),
!:Analyser = !.Analyser ^ search_space := SearchSpace,
!:Analyser = !.Analyser ^ require_explicit := no,
decide_analyser_response(Store, Oracle, Response, !Analyser)
;
MaybeRequireExplicit = no,
%
% An explicit subtree was not requested, so this is the
% start of a new declarative debugging session.
%
reset_analyser(!Analyser),
MaybeWeighting = get_maybe_weighting_from_search_mode(
!.Analyser ^ search_mode),
initialise_search_space(Store, MaybeWeighting, Node, SearchSpace),
!:Analyser = !.Analyser ^ search_space := SearchSpace,
topmost_det(SearchSpace, TopMostId),
!:Analyser = !.Analyser ^ last_search_question :=
yes(suspect_and_reason(TopMostId, ques_reason_start)),
edt_question(Store, Node, Question),
Response = analyser_response_revise(Question)
)
;
AnalysisType = resume_previous,
( reask_last_question(Store, !.Analyser, Response0) ->
Response = Response0
;
decide_analyser_response(Store, Oracle, Response, !Analyser)
)
).
:- func get_maybe_weighting_from_search_mode(search_mode) =
maybe(weighting_heuristic).
get_maybe_weighting_from_search_mode(analyser_divide_and_query(Weighting)) =
yes(Weighting).
get_maybe_weighting_from_search_mode(analyser_top_down) = no.
get_maybe_weighting_from_search_mode(analyser_binary(_, _, _)) = no.
get_maybe_weighting_from_search_mode(analyser_follow_subterm_end(_, _, _,
_, _)) = no.
reask_last_question(Store, Analyser, Response) :-
MaybeLastQuestion = Analyser ^ last_search_question,
MaybeLastQuestion = yes(suspect_and_reason(SuspectId, _)),
SearchSpace = Analyser ^ search_space,
Node = get_edt_node(SearchSpace, SuspectId),
edt_question(Store, Node, OracleQuestion),
Response = analyser_response_oracle_question(OracleQuestion).
continue_analysis(Store, Oracle, Answer, Response, !Analyser) :-
(
!.Analyser ^ last_search_question = yes(
suspect_and_reason(SuspectId, _)),
process_answer(Store, Answer, SuspectId, !Analyser)
;
!.Analyser ^ last_search_question = no,
throw(internal_error("continue_analysis",
"received answer to unasked question"))
),
decide_analyser_response(Store, Oracle, Response, !Analyser).
change_search_mode(Store, Oracle, UserMode, !Analyser, Response) :-
(
UserMode = user_top_down,
set_fallback_search_mode(Store, analyser_top_down, !Analyser)
;
UserMode = user_divide_and_query,
set_fallback_search_mode(Store,
analyser_divide_and_query(number_of_events), !Analyser)
;
UserMode = user_suspicion_divide_and_query,
set_fallback_search_mode(Store, analyser_divide_and_query(suspicion),
!Analyser)
;
UserMode = user_binary,
(
!.Analyser ^ last_search_question =
yes(suspect_and_reason(SuspectId, _)),
setup_binary_search(!.Analyser ^ search_space, SuspectId,
SearchMode),
!:Analyser = !.Analyser ^ search_mode := SearchMode
;
!.Analyser ^ last_search_question = no,
throw(internal_error("change_search_mode",
"binary mode requested, but no last question"))
)
),
decide_analyser_response(Store, Oracle, Response, !Analyser).
:- pred process_answer(S::in, decl_answer(T)::in, suspect_id::in,
analyser_state(T)::in, analyser_state(T)::out) is det <= mercury_edt(S, T).
process_answer(_, skip(_), SuspectId, !Analyser) :-
skip_suspect(SuspectId, !.Analyser ^ search_space, SearchSpace),
!:Analyser = !.Analyser ^ search_space := SearchSpace.
process_answer(Store, ignore(_), SuspectId, !Analyser) :-
ignore_suspect(Store, SuspectId, !.Analyser ^ search_space, SearchSpace),
!:Analyser = !.Analyser ^ search_space := SearchSpace.
process_answer(_, truth_value(_, truth_correct), SuspectId, !Analyser) :-
assert_suspect_is_correct(SuspectId, !.Analyser ^ search_space,
SearchSpace),
!:Analyser = !.Analyser ^ search_space := SearchSpace.
process_answer(_, truth_value(_, truth_inadmissible), SuspectId, !Analyser) :-
assert_suspect_is_inadmissible(SuspectId, !.Analyser ^ search_space,
SearchSpace),
!:Analyser = !.Analyser ^ search_space := SearchSpace.
process_answer(_, truth_value(_, truth_erroneous), SuspectId, !Analyser) :-
assert_suspect_is_erroneous(SuspectId, !.Analyser ^ search_space,
SearchSpace),
!:Analyser = !.Analyser ^ search_space := SearchSpace.
process_answer(Store, suspicious_subterm(Node, ArgPos, TermPath, HowTrack,
ShouldAssertInvalid), SuspectId, !Analyser) :-
%
% XXX The following 2 lines just done so that debugging info can be
% printed for tests run when declarative_analyser.m not compiled with
% tracing (so can't use dd_dd command in mdb). Should be removed when
% edt_dependency becomes stable enough.
%
edt_dependency(Store, Node, ArgPos, TermPath, _, DebugOrigin),
!:Analyser = !.Analyser ^ debug_origin := yes(DebugOrigin),
(
ShouldAssertInvalid = assert_invalid,
edt_subterm_mode(Store, Node, ArgPos, TermPath, Mode),
(
Mode = subterm_in,
assert_suspect_is_inadmissible(SuspectId,
!.Analyser ^ search_space, SearchSpace)
;
Mode = subterm_out,
assert_suspect_is_erroneous(SuspectId,
!.Analyser ^ search_space, SearchSpace)
),
!:Analyser = !.Analyser ^ search_space := SearchSpace
;
ShouldAssertInvalid = no_assert_invalid
),
!:Analyser = !.Analyser ^ search_mode :=
analyser_follow_subterm_end(SuspectId, ArgPos, TermPath, no, HowTrack).
revise_analysis(Store, Response, !Analyser) :-
SearchSpace = !.Analyser ^ search_space,
( root(SearchSpace, RootId) ->
Node = get_edt_node(!.Analyser ^ search_space, RootId),
edt_question(Store, Node, Question),
Response = analyser_response_revise(Question),
revise_root(Store, SearchSpace, SearchSpace1),
!:Analyser = !.Analyser ^ search_space := SearchSpace1,
!:Analyser = !.Analyser ^ last_search_question :=
yes(suspect_and_reason(RootId, ques_reason_revise)),
!:Analyser = !.Analyser ^ search_mode :=
!.Analyser ^ fallback_search_mode
;
% There must be a root, since a bug was found (and is now
% being revised).
throw(internal_error("revise_analysis", "no root"))
).
:- pred decide_analyser_response(S::in, oracle_state::in,
analyser_response(T)::out, analyser_state(T)::in,
analyser_state(T)::out) is det <= mercury_edt(S, T).
decide_analyser_response(Store, Oracle, Response, !Analyser) :-
maybe_check_search_space_consistency(Store, !.Analyser ^ search_space,
"Start of decide_analyser_response"),
some [!SearchSpace] (
!:SearchSpace = !.Analyser ^ search_space,
search(Store, Oracle, !SearchSpace, !.Analyser ^ search_mode,
!.Analyser ^ fallback_search_mode, NewMode, SearchResponse),
!:Analyser = !.Analyser ^ search_space := !.SearchSpace,
!:Analyser = !.Analyser ^ search_mode := NewMode,
handle_search_response(Store, SearchResponse, !Analyser, Response)
),
maybe_check_search_space_consistency(Store, !.Analyser ^ search_space,
"End of decide_analyser_response").
:- pred handle_search_response(S::in, search_response::in,
analyser_state(T)::in, analyser_state(T)::out,
analyser_response(T)::out) is det <= mercury_edt(S, T).
handle_search_response(Store, search_response_question(SuspectId, Reason),
!Analyser, Response) :-
SearchSpace = !.Analyser ^ search_space,
Node = get_edt_node(SearchSpace, SuspectId),
edt_question(Store, Node, OracleQuestion),
(
(
suspect_unknown(SearchSpace, SuspectId)
;
suspect_skipped(SearchSpace, SuspectId)
)
->
Response = analyser_response_oracle_question(OracleQuestion)
;
suspect_ignored(SearchSpace, SuspectId)
->
% Searches should not respond with questions about suspects we
% already know to be trusted.
throw(internal_error("handle_search_response",
"search responded with query about ignored suspect"))
;
% We already known something about this suspect, but the search
% wants the oracle to be requeried. This may happen if the
% search thinks the user might have answered the question
% incorrectly before.
Response = analyser_response_revise(OracleQuestion)
),
!:Analyser = !.Analyser ^ last_search_question :=
yes(suspect_and_reason(SuspectId, Reason)).
handle_search_response(_, search_response_require_explicit_subtree(SuspectId),
!Analyser, Response) :-
!:Analyser = !.Analyser ^ require_explicit := yes(explicit_subtree(
SuspectId)),
Node = get_edt_node(!.Analyser ^ search_space, SuspectId),
Response = analyser_response_require_explicit_subtree(Node).
handle_search_response(_, search_response_require_explicit_supertree,
!Analyser, Response) :-
!:Analyser = !.Analyser ^ require_explicit := yes(explicit_supertree),
SearchSpace = !.Analyser ^ search_space,
topmost_det(SearchSpace, TopMostId),
TopMost = get_edt_node(SearchSpace, TopMostId),
Response = analyser_response_require_explicit_supertree(TopMost).
handle_search_response(_, search_response_no_suspects, !Analyser,
analyser_response_no_suspects).
handle_search_response(Store,
search_response_found_bug(BugId, CorrectDescendents,
InadmissibleChildren), !Analyser, Response) :-
bug_response(Store, !.Analyser ^ search_space, BugId,
[BugId | CorrectDescendents], InadmissibleChildren, Response).
% bug_response(Store, SearchSpace, BugId, Evidence,
% InadmissibleChildren, Response)
% Create a bug analyser-response using the given Evidence. If
% InadmissibleChildren isn't empty then an i_bug will be created,
% otherwise an e_bug will be created.
%
:- pred bug_response(S::in, search_space(T)::in,
suspect_id::in, list(suspect_id)::in, list(suspect_id)::in,
analyser_response(T)::out) is det <= mercury_edt(S, T).
bug_response(Store, SearchSpace, BugId, Evidence, InadmissibleChildren,
Response) :-
BugNode = get_edt_node(SearchSpace, BugId),
(
InadmissibleChildren = [InadmissibleChild | _],
edt_get_i_bug(Store, BugNode,
get_edt_node(SearchSpace, InadmissibleChild), IBug),
Bug = i_bug(IBug)
;
InadmissibleChildren = [],
edt_get_e_bug(Store, BugNode, EBug),
Bug = e_bug(EBug)
),
EDTNodes = list.map(get_edt_node(SearchSpace), Evidence),
list.map(edt_question(Store), EDTNodes,
EvidenceAsQuestions),
Response = analyser_response_bug_found(Bug, EvidenceAsQuestions).
%-----------------------------------------------------------------------------%
% Search the search space for a question for the oracle. The search
% should respond with a question about a suspect, or a request for an
% explicit subtree to be generated. A new search mode is returned so
% that the search algorithm being used can remember its current state
% next time round.
%
:- pred search(S::in, oracle_state::in,
search_space(T)::in, search_space(T)::out,
search_mode::in, search_mode::in,
search_mode::out, search_response::out) is det <= mercury_edt(S, T).
search(Store, Oracle, !SearchSpace, analyser_top_down, FallBackSearchMode,
NewMode, Response) :-
top_down_search(Store, Oracle, !SearchSpace, Response),
% We always go back to the fallback search mode after a top-down
% search, because some fallback searches (such as divide and query)
% use top-down as a fail safe and we want the fallback search to
% resume after the top-down search.
NewMode = FallBackSearchMode.
search(Store, Oracle, !SearchSpace, SearchMode, FallBackSearchMode,
NewMode, Response) :-
SearchMode = analyser_follow_subterm_end(SuspectId, ArgPos, TermPath,
LastUnknown, HowTrack),
follow_subterm_end_search(Store, Oracle, !SearchSpace, HowTrack,
LastUnknown, SuspectId, ArgPos, TermPath, FallBackSearchMode,
NewMode, Response).
search(Store, Oracle, !SearchSpace, SearchMode, FallBackSearchMode, NewMode,
Response) :-
SearchMode = analyser_binary(PathArray, Top - Bottom, LastTested),
binary_search(Store, Oracle, PathArray, Top, Bottom, LastTested,
!SearchSpace, FallBackSearchMode, NewMode, Response).
search(Store, Oracle, !SearchSpace, analyser_divide_and_query(Weighting), _,
NewMode, Response) :-
divide_and_query_search(Store, Oracle, Weighting, !SearchSpace,
Response, NewMode).
:- pred top_down_search(S::in, oracle_state::in,
search_space(T)::in, search_space(T)::out,
search_response::out) is det <= mercury_edt(S, T).
top_down_search(Store, Oracle, !SearchSpace, Response) :-
%
% If there's no root yet (because the oracle hasn't asserted any nodes
% are erroneous yet) then use the topmost suspect as a starting point.
%
( root(!.SearchSpace, RootId) ->
Start = RootId
;
topmost_det(!.SearchSpace, Start)
),
first_unknown_descendent(Store, Oracle, Start, !SearchSpace,
MaybeUnknownDescendent),
(
MaybeUnknownDescendent = found(Unknown),
Response = search_response_question(Unknown, ques_reason_top_down)
;
MaybeUnknownDescendent = not_found,
(
choose_skipped_suspect(!.SearchSpace, SkippedSuspect)
->
Response = search_response_question(SkippedSuspect,
ques_reason_skipped)
;
% Since the are no skipped suspects and no unknown
% suspects in the search space, if there is a root
% (i.e. an erroneous suspect), then it must be a bug.
% Note that only top down search actually checks if a
% bug was found. This is okay, since all the other
% search algorithms call top down search if they can't
% find an unknown suspect.
root(!.SearchSpace, BugId)
->
(
children(Store, Oracle, BugId, !SearchSpace, BugChildren),
non_ignored_descendents(Store, Oracle, BugChildren,
!SearchSpace, NonIgnoredDescendents),
list.filter(suspect_correct_or_inadmissible(!.SearchSpace),
NonIgnoredDescendents, CorrectDescendents, [])
->
list.filter(suspect_inadmissible(!.SearchSpace), BugChildren,
InadmissibleChildren),
Response = search_response_found_bug(BugId, CorrectDescendents,
InadmissibleChildren)
;
throw(internal_error("top_down_search",
"bug has unexplored or unknown children"))
)
;
% Try to extend the search space upwards. If this fails
% and we're not at the topmost traced node, then request that
% an explicit supertree be generated.
(
extend_search_space_upwards(Store, Oracle, !.SearchSpace,
ExtendedSearchSpace)
->
top_down_search(Store, Oracle, ExtendedSearchSpace,
!:SearchSpace, Response)
;
topmost_det(!.SearchSpace, TopMostId),
TopMostNode = get_edt_node(!.SearchSpace, TopMostId),
( edt_topmost_node(Store, TopMostNode) ->
% We can't look any higher.
Response = search_response_no_suspects
;
Response = search_response_require_explicit_supertree
)
)
)
;
MaybeUnknownDescendent = require_explicit_subtree(RequireExplicitId),
Response = search_response_require_explicit_subtree(RequireExplicitId)
).
:- pred follow_subterm_end_search(S::in, oracle_state::in,
search_space(T)::in, search_space(T)::out, how_track_subterm::in,
maybe(suspect_id)::in, suspect_id::in,
arg_pos::in, term_path::in, search_mode::in, search_mode::out,
search_response::out) is det <= mercury_edt(S, T).
follow_subterm_end_search(Store, Oracle, !SearchSpace, HowTrack,
LastUnknown, SuspectId, ArgPos, TermPath, FallBackSearchMode,
NewMode, SearchResponse) :-
follow_subterm_end_search_2(Store, Oracle, !SearchSpace, HowTrack,
map.init, _, LastUnknown, SuspectId, ArgPos, TermPath,
FallBackSearchMode, NewMode, SearchResponse).
:- pred follow_subterm_end_search_2(S::in, oracle_state::in,
search_space(T)::in, search_space(T)::out, how_track_subterm::in,
map(proc_layout, unit)::in, map(proc_layout, unit)::out,
maybe(suspect_id)::in, suspect_id::in,
arg_pos::in, term_path::in, search_mode::in, search_mode::out,
search_response::out) is det <= mercury_edt(S, T).
follow_subterm_end_search_2(Store, Oracle, !SearchSpace, HowTrack,
!TriedShortcutProcs, LastUnknown, SuspectId, ArgPos, TermPath,
FallBackSearchMode, NewMode, SearchResponse) :-
find_subterm_origin(Store, Oracle, SuspectId, ArgPos, TermPath, HowTrack,
!TriedShortcutProcs, !SearchSpace, FindOriginResponse),
(
FindOriginResponse = primitive_op(BindingSuspectId, FileName,
LineNo, PrimOpType, Output),
ProcLabel = get_proc_label_for_suspect(Store, !.SearchSpace,
BindingSuspectId),
(
Output = yes,
% BindingSuspectId = SuspectId since the
% subterm is an output of SuspectId.
BindingNode = get_edt_node(!.SearchSpace, SuspectId),
ArgNum = edt_arg_pos_to_user_arg_num(Store, BindingNode, ArgPos),
MaybePath = yes([ArgNum | TermPath])
;
Output = no,
% Since the subterm is not an output of the
% binding node, it will not appear in any of the
% arguments of the binding node (it can't be an
% input, because then it would have been bound outside
% the node).
MaybePath = no
),
(
% We ask about the binding node even if it was
% previously skipped, since this behaviour is
% more predictable from the user's perspective.
%
( suspect_unknown(!.SearchSpace, BindingSuspectId)
; suspect_skipped(!.SearchSpace, BindingSuspectId)
)
->
SearchResponse = search_response_question(BindingSuspectId,
ques_reason_binding_node(PrimOpType, FileName, LineNo,
MaybePath, ProcLabel, no)),
NewMode = FallBackSearchMode
;
(
LastUnknown = yes(Unknown),
suspect_still_unknown(!.SearchSpace, Unknown)
->
Reason = ques_reason_binding_node(PrimOpType,
FileName, LineNo, MaybePath, ProcLabel, yes),
SearchResponse = search_response_question(Unknown, Reason),
NewMode = FallBackSearchMode
;
search(Store, Oracle, !SearchSpace, FallBackSearchMode,
FallBackSearchMode, NewMode, SearchResponse)
)
)
;
FindOriginResponse = not_found,
(
LastUnknown = yes(Unknown),
suspect_still_unknown(!.SearchSpace, Unknown)
->
SearchResponse = search_response_question(Unknown,
ques_reason_subterm_no_proc_rep),
NewMode = FallBackSearchMode
;
search(Store, Oracle, !SearchSpace,
FallBackSearchMode, FallBackSearchMode,
NewMode, SearchResponse)
)
;
FindOriginResponse = require_explicit_subtree,
SearchResponse = search_response_require_explicit_subtree(SuspectId),
%
% Record the current position of the search so
% we can continue where we left off once the explicit
% subtree has been generated.
%
NewMode = analyser_follow_subterm_end(SuspectId, ArgPos, TermPath,
LastUnknown, HowTrack)
;
FindOriginResponse = require_explicit_supertree,
SearchResponse = search_response_require_explicit_supertree,
NewMode = analyser_follow_subterm_end(SuspectId, ArgPos, TermPath,
LastUnknown, HowTrack)
;
FindOriginResponse = origin(OriginId, OriginArgPos,
OriginTermPath, SubtermMode),
(
suspect_unknown(!.SearchSpace, OriginId)
->
NewLastUnknown = yes(OriginId)
;
NewLastUnknown = LastUnknown
),
(
%
% Check if it's worth continuing tracking the sub-term.
% We want to stop if we enter a portion of the search
% space known not to contain the bug from which we
% can't return (for example if we come across an
% erroneous node where the sub-term is an input).
%
give_up_subterm_tracking(!.SearchSpace, OriginId, SubtermMode)
->
(
LastUnknown = yes(Unknown),
suspect_still_unknown(!.SearchSpace, Unknown)
->
SearchResponse = search_response_question(Unknown,
ques_reason_binding_node_eliminated),
NewMode = FallBackSearchMode
;
search(Store, Oracle, !SearchSpace,
FallBackSearchMode, FallBackSearchMode,
NewMode, SearchResponse)
)
;
%
% This recursive call will not lead to an infinite loop
% because eventually either the sub-term will be bound
% (and find_subterm_origin will respond with
% primitive_op/3) or there will be insufficient tracing
% information to continue (and find_subterm_origin will
% respond with not_found).
%
follow_subterm_end_search_2(Store, Oracle, !SearchSpace, HowTrack,
!TriedShortcutProcs, NewLastUnknown, OriginId,
OriginArgPos, OriginTermPath,
FallBackSearchMode, NewMode, SearchResponse)
)
).
% setup_binary_search(SearchSpace, SuspectId, SearchMode).
% Sets up the search mode to do a binary search between SuspectId
% and either the root of the search space if a suspect has
% previously been marked erroneous, or the topmost node if no suspect
% has yet been marked erroneous.
%
:- pred setup_binary_search(search_space(T)::in, suspect_id::in,
search_mode::out) is det.
setup_binary_search(SearchSpace, SuspectId, SearchMode) :-
( root(SearchSpace, RootId) ->
TopId = RootId,
BottomId = SuspectId
;
topmost_det(SearchSpace, TopId),
BottomId = SuspectId
),
( get_path(SearchSpace, BottomId, TopId, Path) ->
PathArray = array.from_list(Path),
array.bounds(PathArray, Top, Bottom),
SearchMode = analyser_binary(PathArray, Top - Bottom, Bottom)
;
throw(internal_error("setup_binary_search",
"TopId not an ancestor of BottomId"))
).
:- pred binary_search(S::in, oracle_state::in,
array(suspect_id)::in, int::in, int::in, int::in,
search_space(T)::in, search_space(T)::out, search_mode::in,
search_mode::out, search_response::out) is det <= mercury_edt(S, T).
binary_search(Store, Oracle, PathArray, Top, Bottom, LastTested,
!SearchSpace, FallBackSearchMode, NewMode, Response) :-
SuspectId = PathArray ^ elem(LastTested),
%
% Check what the result of the query about LastTested was and adjust
% the range appropriately.
%
(
% The oracle answered `erroneous'.
suspect_in_excluded_complement(!.SearchSpace, SuspectId)
->
NewTop = LastTested + 1,
NewBottom = Bottom
;
% The oracle answered `correct' or `inadmissible'
suspect_in_excluded_subtree(!.SearchSpace, SuspectId)
->
NewTop = Top,
NewBottom = LastTested - 1
;
% The suspect is trusted(ignored) or was skipped.
NewTop = Top,
NewBottom = Bottom
),
(
NewTop > NewBottom
->
% Revert to the fallback search mode when binary search is over.
search(Store, Oracle, !SearchSpace,
FallBackSearchMode, FallBackSearchMode, NewMode, Response)
;
(
find_unknown_closest_to_middle(!.SearchSpace, PathArray,
NewTop, NewBottom, UnknownClosestToMiddle)
->
NewMode = analyser_binary(PathArray, NewTop - NewBottom,
UnknownClosestToMiddle),
Response = search_response_question(
PathArray ^ elem(UnknownClosestToMiddle),
ques_reason_binary(NewBottom, NewTop, UnknownClosestToMiddle))
;
% No unknown suspects on the path, so revert to
% the fallback search mode.
search(Store, Oracle, !SearchSpace,
FallBackSearchMode, FallBackSearchMode, NewMode, Response)
)
).
% find_unknown_closest_to_middle(SearchSpace, PathArray, Top, Bottom,
% Unknown):
%
% Unknown is the position in PathArray of the suspect which has status
% unknown and is closest to halfway between From and To which are
% also indexes into PathArray. Fails if there are no unknown suspects
% between From and To (inclusive).
%
:- pred find_unknown_closest_to_middle(search_space(T)::in,
array(suspect_id)::in, int::in, int::in, int::out) is semidet.
find_unknown_closest_to_middle(SearchSpace, PathArray, Top, Bottom, Unknown) :-
Middle = Top + ((Bottom - Top) // 2),
find_unknown_closest_to_range(SearchSpace, PathArray, Top, Bottom,
Middle, Middle, Unknown).
% find_unknown_closest_to_range(SearchSpace, PathArray, OuterTop,
% OuterBottom, InnerTop, InnerBottom, Unknown):
%
% Unknown is a position in PathArray between OuterTop and OuterBottom
% (inclusive) where the status of the suspect is unknown. The preferred
% position to return is as close as possible to InnerTop and
% InnerBottom, with the proviso that elements between InnerTop and
% InnerBottom (exclusive) aren't tested, since the caller has already
% found they were not unknown.
%
:- pred find_unknown_closest_to_range(search_space(T)::in,
array(suspect_id)::in, int::in, int::in, int::in, int::in, int::out)
is semidet.
find_unknown_closest_to_range(SearchSpace, PathArray, OuterTop, OuterBottom,
InnerTop, InnerBottom, Unknown) :-
InnerTop =< InnerBottom,
( OuterTop =< InnerTop ; InnerBottom =< OuterBottom ),
(
OuterTop =< InnerTop,
suspect_unknown(SearchSpace, PathArray ^ elem(InnerTop))
->
Unknown = InnerTop
;
InnerBottom =< OuterBottom,
suspect_unknown(SearchSpace, PathArray ^ elem(InnerBottom))
->
Unknown = InnerBottom
;
find_unknown_closest_to_range(SearchSpace, PathArray,
OuterTop, OuterBottom, InnerTop - 1, InnerBottom + 1, Unknown)
).
:- pred divide_and_query_search(S::in, oracle_state::in,
weighting_heuristic::in, search_space(T)::in, search_space(T)::out,
search_response::out, search_mode::out) is det <= mercury_edt(S, T).
divide_and_query_search(Store, Oracle, Weighting, !SearchSpace,
Response, analyser_divide_and_query(Weighting)) :-
% If there's no root yet (because the oracle hasn't asserted any nodes
% are erroneous yet), then use top-down search.
( root(!.SearchSpace, RootId) ->
( children(Store, Oracle, RootId, !SearchSpace, Children) ->
find_middle_weight(Store, Oracle, Weighting, Children,
RootId, no, !SearchSpace, Response)
;
Response = search_response_require_explicit_subtree(RootId)
)
;
top_down_search(Store, Oracle, !SearchSpace, Response)
).
% Call find_middle_weight if we are able to find the children of the
% given suspect id, otherwise return a require_explicit_subtree
% search response in the last argument.
%
:- pred find_middle_weight_if_children(S::in,
oracle_state::in, weighting_heuristic::in, suspect_id::in,
suspect_id::in, maybe(suspect_id)::in,
search_space(T)::in, search_space(T)::out, search_response::out)
is det <= mercury_edt(S, T).
find_middle_weight_if_children(Store, Oracle, Weighting, SuspectId, TopId,
MaybeLastUnknown, !SearchSpace, Response) :-
( children(Store, Oracle, SuspectId, !SearchSpace, Children) ->
find_middle_weight(Store, Oracle, Weighting, Children, TopId,
MaybeLastUnknown, !SearchSpace, Response)
;
Response = search_response_require_explicit_subtree(SuspectId)
).
% find_middle_weight(Store, Oracle, Weighting, SuspectIds,
% TopId, MaybeLastUnknown, !SearchSpace, Response).
% Find the unknown suspect whose weight is closest to half the weight
% of TopId, considering only the heaviest suspect in SuspectIds, the
% heaviest child of the heaviest suspect in SuspectIds and so on.
% MaybeLastUnknown is the last node that was unknown in the search (if
% any).
%
:- pred find_middle_weight(S::in, oracle_state::in,
weighting_heuristic::in, list(suspect_id)::in, suspect_id::in,
maybe(suspect_id)::in, search_space(T)::in, search_space(T)::out,
search_response::out) is det <= mercury_edt(S, T).
find_middle_weight(Store, Oracle, Weighting, [], TopId,
MaybeLastUnknown, !SearchSpace, Response) :-
(
MaybeLastUnknown = yes(LastUnknown),
suspect_still_unknown(!.SearchSpace, LastUnknown)
->
Response = search_response_question(LastUnknown,
ques_reason_divide_and_query(Weighting,
get_weight(!.SearchSpace, TopId),
get_weight(!.SearchSpace, LastUnknown)))
;
% This could happen when there were no unknown suspects
% encountered during the search, in which case we revert
% to top-down search.
top_down_search(Store, Oracle, !SearchSpace, Response)
).
find_middle_weight(Store, Oracle, Weighting, [SuspectId | SuspectIds], TopId,
MaybeLastUnknown, !SearchSpace, Response) :-
TopWeight = get_weight(!.SearchSpace, TopId),
Target = TopWeight // 2,
%
% Find the heaviest suspect:
%
Weight = get_weight(!.SearchSpace, SuspectId),
list.foldl2(max_weight(!.SearchSpace), SuspectIds,
Weight, MaxWeight, SuspectId, Heaviest),
( MaxWeight > Target ->
( suspect_unknown(!.SearchSpace, Heaviest) ->
NewMaybeLastUnknown = yes(Heaviest)
;
NewMaybeLastUnknown = MaybeLastUnknown
),
find_middle_weight_if_children(Store, Oracle, Weighting, Heaviest,
TopId, NewMaybeLastUnknown, !SearchSpace, Response)
;
( suspect_unknown(!.SearchSpace, Heaviest) ->
(
MaybeLastUnknown = yes(LastUnknown),
suspect_still_unknown(!.SearchSpace, LastUnknown)
->
LastUnknownWeight = get_weight(!.SearchSpace, LastUnknown),
%
% If the last unknown suspect was closer to
% the target weight then ask about it.
%
( LastUnknownWeight - Target < Target - MaxWeight ->
Response = search_response_question(LastUnknown,
ques_reason_divide_and_query(Weighting, TopWeight,
LastUnknownWeight))
;
Response = search_response_question(Heaviest,
ques_reason_divide_and_query(Weighting, TopWeight,
MaxWeight))
)
;
Response = search_response_question(Heaviest,
ques_reason_divide_and_query(Weighting, TopWeight,
MaxWeight))
)
;
(
MaybeLastUnknown = yes(LastUnknown),
suspect_still_unknown(!.SearchSpace, LastUnknown)
->
LastUnknownWeight = get_weight(!.SearchSpace, LastUnknown),
Response = search_response_question(LastUnknown,
ques_reason_divide_and_query(Weighting, TopWeight,
LastUnknownWeight))
;
% Look deeper until we find an unknown:
find_middle_weight_if_children(Store, Oracle, Weighting,
Heaviest, TopId, no, !SearchSpace, Response)
)
)
).
:- pred max_weight(search_space(T)::in, suspect_id::in,
int::in, int::out, suspect_id::in, suspect_id::out) is det.
max_weight(SearchSpace, SuspectId, PrevMax, NewMax,
PrevSuspectId, NewSuspectId) :-
Weight = get_weight(SearchSpace, SuspectId),
( Weight > PrevMax ->
NewMax = Weight,
NewSuspectId = SuspectId
;
NewMax = PrevMax,
NewSuspectId = PrevSuspectId
).
%-----------------------------------------------------------------------------%
% Check that a suspect is still unknown. This is called by the search
% algorithms to make double sure that a suspect is still unknown (it
% might not be unknown if, for example, an erroneous suspect was added
% to the search space during the search).
%
:- pred suspect_still_unknown(search_space(T)::in, suspect_id::in) is semidet.
suspect_still_unknown(SearchSpace, SuspectId) :-
suspect_unknown(SearchSpace, SuspectId).
%-----------------------------------------------------------------------------%
reason_to_string(ques_reason_start) =
"this is the node where the `dd' command was issued.".
reason_to_string(ques_reason_binding_node(PrimOpType, FileName, LineNo,
MaybePath, ProcLabel, Eliminated)) = Str :-
PrimOpStr = primitive_op_type_to_string(PrimOpType),
LineNoStr = int_to_string(LineNo),
get_pred_attributes(ProcLabel, SymModule, Name, Arity, PredOrFunc),
(
PredOrFunc = pf_function,
PredOrFuncStr = "function"
;
PredOrFunc = pf_predicate,
PredOrFuncStr = "predicate"
),
Module = sym_name_to_string(SymModule),
ArityStr = int_to_string(Arity),
(
Eliminated = yes,
EliminatedSent = " That node was, however, previously "
++ "eliminated from the bug search."
;
Eliminated = no,
EliminatedSent = ""
),
(
MaybePath = yes(Path),
PathStrings = list.map(int_to_string, Path),
PathStr = string.join_list("/", PathStrings),
PathSent = "The path to the subterm in the atom is " ++ PathStr ++ "."
;
MaybePath = no,
PathSent = ""
),
Str = "the marked subterm was bound by the " ++
PrimOpStr ++ " inside the " ++ PredOrFuncStr ++
" " ++ Module ++ "." ++ Name ++ "/" ++ ArityStr ++
" (" ++ FileName ++ ":" ++ LineNoStr ++ "). " ++
PathSent ++ EliminatedSent.
reason_to_string(ques_reason_top_down) =
"this is the next node in the top-down search.".
reason_to_string(ques_reason_subterm_no_proc_rep) =
"tracking of the marked subterm had to be aborted here, because of "
++ "missing tracing information.".
reason_to_string(ques_reason_binding_node_eliminated) =
"tracking of the marked subterm was stopped here, because the binding "
++ "node lies in a portion of the tree which has been eliminated.".
reason_to_string(ques_reason_binary(Bottom, Top, Split)) = Str :-
PathLengthStr = int_to_string_thousands(Bottom - Top + 1),
SubPath1LengthStr = int_to_string_thousands(Bottom - Split),
SubPath2LengthStr = int_to_string_thousands(Split - Top + 1),
Str = "this node divides a path of length " ++ PathLengthStr
++ " into two paths of length " ++
SubPath1LengthStr ++ " and " ++ SubPath2LengthStr ++ ".".
reason_to_string(ques_reason_divide_and_query(Weighting, OldWeight,
SubtreeWeight)) =
weighting_to_reason_string(Weighting, OldWeight - SubtreeWeight,
SubtreeWeight).
reason_to_string(ques_reason_skipped) =
"there are no more non-skipped questions left.".
reason_to_string(ques_reason_revise) =
"this question is being revisited, because of "
++ "an unsuccessful previous bug search.".
:- func weighting_to_reason_string(weighting_heuristic, int, int) = string.
weighting_to_reason_string(number_of_events, Weight1, Weight2) = Str :-
Weight1Str = int_to_string_thousands(Weight1),
Weight2Str = int_to_string_thousands(Weight2),
Str = "this node divides the suspect area into two regions of "
++ Weight1Str ++ " and " ++ Weight2Str ++ " events each.".
weighting_to_reason_string(suspicion, Weight1, Weight2) = Str :-
Weight1Str = int_to_string_thousands(Weight1),
Weight2Str = int_to_string_thousands(Weight2),
Str = "this node divides the suspect area into " ++
"two regions of suspicion " ++ Weight1Str ++ " and
" ++ Weight2Str ++ ".".
show_info(Store, OutStream, Analyser, !IO) :-
SearchSpace = Analyser ^ search_space,
some [!FieldNames, !Data] (
!:FieldNames = [],
!:Data = [],
%
% Get the context of the current question.
%
(
Analyser ^ last_search_question =
yes(suspect_and_reason(LastId, Reason)),
(
edt_context(Store, get_edt_node(SearchSpace,
LastId), FileName - LineNo, MaybeReturnContext)
->
(
MaybeReturnContext = yes(ReturnFileName - ReturnLineNo),
ContextStr = FileName ++ ":" ++ int_to_string(LineNo)
++ " (" ++ ReturnFileName ++ ":"
++ int_to_string(ReturnLineNo) ++ ")"
;
MaybeReturnContext = no,
ContextStr = FileName ++ ":" ++ int_to_string(LineNo)
),
list.append(!.FieldNames, ["Context of current question"],
!:FieldNames),
list.append(!.Data, [ContextStr], !:Data)
;
true
)
;
Analyser ^ last_search_question = no,
throw(internal_error("show_info", "no last question"))
),
list.append(!.FieldNames, ["Search mode"],
!:FieldNames),
list.append(!.Data, [search_mode_to_string(
Analyser ^ search_mode)], !:Data),
MaybeWeighting = get_current_maybe_weighting(SearchSpace),
( MaybeWeighting = yes(number_of_events) ->
( root(SearchSpace, RootId) ->
StartId = RootId
;
topmost_det(SearchSpace, StartId)
),
Weight = get_weight(SearchSpace, StartId),
(
Analyser ^ search_mode =
analyser_divide_and_query(number_of_events)
->
list.append(!.FieldNames, ["Estimated questions remaining"],
!:FieldNames),
EstimatedQuestions = float.ceiling_to_int(
math.log2(float(Weight))),
list.append(!.Data, [int_to_string(EstimatedQuestions)],
!:Data)
;
true
),
list.append(!.FieldNames, ["Number of suspect events"],
!:FieldNames),
list.append(!.Data, [int_to_string_thousands(Weight)], !:Data)
;
true
),
InfoMessage = string.format_table([left(!.FieldNames), left(!.Data)],
" : ")
),
ReasonStr = reason_to_string(Reason),
ReasonSent = "The current question was chosen because " ++ ReasonStr,
WrappedReason = string.word_wrap(ReasonSent, 72),
io.format(OutStream, "%s\n%s\n", [s(InfoMessage), s(WrappedReason)], !IO).
:- func search_mode_to_string(search_mode) = string.
search_mode_to_string(analyser_top_down) = "top down".
search_mode_to_string(analyser_follow_subterm_end(_, _, _, _,
track_accurate)) =
"tracking marked sub-term (using accurate algorithm)".
search_mode_to_string(analyser_follow_subterm_end(_, _, _, _,
track_fast)) =
"tracking marked sub-term (using fast algorithm)".
search_mode_to_string(analyser_binary(_, _, _)) = "binary search on path".
search_mode_to_string(analyser_divide_and_query(number_of_events)) =
"divide and query".
search_mode_to_string(analyser_divide_and_query(suspicion)) =
"suspicion divide and query".
Reference in New Issue View Git Blame Copy Permalink