Commit Graph

141 Commits

Author SHA1 Message Date
Zoltan Somogyi
e4c75b250b Improve programming style. 2023-03-12 16:23:21 +08:00
Julien Fischer
0a8d19b85e Update a link to the papers page.
compiler/accumulator.m:
    As above.
2023-02-14 15:01:03 +11:00
Zoltan Somogyi
307b1dc148 Split up error_util.m into five modules.
compiler/error_spec.m:
    This new module contains the part of the old error_util.m that defines
    the error_spec type, and some functions that can help construct pieces
    of error_specs. Most modules of the compiler that deal with errors
    will need to import only this part of the old error_util.m.

    This change also renames the format_component type to format_piece,
    which matches our long-standing naming convention for variables containing
    (lists of) values of this type.

compiler/write_error_spec.m:
    This new module contains the part of the old error_util.m that
    writes out error specs, and converts them to strings.

    This diff marks as obsolete the versions of predicates that
    write out error specs to the current output stream, without
    *explicitly* specifying the intended stream.

compiler/error_sort.m:
    This new module contains the part of the old error_util.m that
    sorts lists of error specs and error msgs.

compiler/error_type_util.m:
    This new module contains the part of the old error_util.m that
    convert types to format_pieces that generate readable output.

compiler/parse_tree.m:
compiler/notes/compiler_design.html:
    Include and document the new modules.

compiler/error_util.m:
    The code remaining in the original error_util.m consists of
    general utility predicates and functions that don't fit into
    any of the modules above.

    Delete an unneeded pair of I/O states from the argument list
    of a predicate.

compiler/file_util.m:
    Move the unable_to_open_file predicate here from error_util.m,
    since it belongs here. Mark another predicate that writes
    to the current output stream as obsolete.

compiler/hlds_error_util.m:
    Mark two predicates that wrote out error_spec to the current output
    stream as obsolete, and add versions that take an explicit output stream.

compiler/Mercury.options:
    Compile the modules that call the newly obsoleted predicates
    with --no-warn-obsolete, for the time being.

compiler/*.m:
    Conform to the changes above, mostly by updating import_module
    declarations, and renaming format_component to format_piece.
2022-10-12 20:50:16 +11:00
Zoltan Somogyi
07f877bc3f Carve term_context.m out of term.m.
library/term.m:
library/term_context.m:
    As above.

    Rename the term.context type as term_context.term_context, with
    term.context now being defined as an equivalence type.

    Replace the context_init function and predicate and the dummy_context_init
    function with just one function: dummy_context. This name includes
    the important part (the fact that it return a *dummy* context) and deletes
    the nonimportant part (dummy contexts are just about never updated,
    so the function does not really "initialize" them).

    Reduce function/predicate pairs that do the same thing to just a function.

library/MODULES_DOC:
library/library.m:
    Add the new module to the list of standard library modules.

NEWS:
    Mention the new module, and the obsoleting of the moved predicates
    and functions in term.m.

compiler/*.m:
library/*.m:
    Conform to the changes above.
2022-08-23 12:56:37 +10:00
Zoltan Somogyi
2a1c2bb88a Make quantification using var_tables the default.
compiler/quantification.m:
    Add a "_vs" suffix to the names of predicates that use varsets, and
    delete the "_vt" suffix from the names of predicates that use var_tables.

    Keep private a predicate that now has no callers outside this module.

    Shorten the names of some function symbols.

compiler/recompute_instmap_deltas.m:
    Shorten the names of some function symbols.

compiler/equiv_type_hlds.m:
    Give a predicate a more meaningful name.

compiler/*.m:
    Conform to the change above.
2022-08-18 20:36:18 +10:00
Zoltan Somogyi
d787ee9355 Store var_tables in proc_infos.
This fixes the performance problem reported in Mantis bug #562.

compiler/hlds_pred.m:
    Instead of storing a varset and a vartypes in each proc_info,
    store just a var_table. Update the predicates that create
    or clone procedures accordingly.

    Where we had operations on proc_infos that had two versions,
    one operating on a varset/vartypes pair and one operating on var_table,
    keep only the latter, with the (shorter) name of the former.

    Delete the arity argument of proc_info_init, because the only
    valid value of that argument is the length of the list of the
    argument types. (In other words, this arg has been redundant
    all along.)

    Change the operations that create new variables in a procedure
    to get the caller to specify the (base) name of the new variable
    up front.

    Delete the unused predicate proc_info_ensure_unique_names.

compiler/type_util.m:
    Due to the change above, we now construct var_tables during the
    construction of the HLDS. The code that does that needs to fill in
    the field that says whether the type of each variable in the table
    is a dummy type or not. However, at this time, the pass that decides
    type representations has not been run yet. The code of is_type_a_dummy
    used to throw an exception in such situations.

    Change this so that in such situations, is_type_a_dummy returns
    a placeholder, not-guaranteed-to-be-correct value. Document why
    this is ok.

compiler/post_typecheck.m:
    Replace the placeholder values in vte_is_dummy fields in all
    the entries in the var_tables in all (valid) predicates with valid data.
    (If there are any invalid predicates, the compilation will fail anyway.)
    The clause_to_proc pass will copy these updated var_tables
    to be the initial var_tables in procedures.

compiler/make_goal.m:
    Change the operations that create new variables in a procedure
    to get the caller to specify the (base) name of the new variable
    up front. This is simpler than the old method, which created new
    variables without a name, and had the caller give them a name as
    a separate operation. And since var_tables need this info,
    get the caller to also specify whether the type is a dummy,
    if the type is not a builtin type which is known not to be a dummy.

compiler/var_table.m:
    Document the times when the types and is_dummy fields in var_table
    entries become meaningful.

    Fix a potential bug: when performing type substitutions in
    var_table entries, updating a variable's type may change whether
    that variable is a dummy or not, so recompute that info.
    It is quite possible that we *never* replace a nondummy type
    with a dummy type or vice versa, but in the absence of a convincing
    correctness argument for that proposition, better safe than sorry.

    Export the previously-private predicate transform_var_table
    to post_typecheck.

    Add code to implement the unused predicate deleted from hlds_pred.m:
    at the time I wrote it, I haven't yet realised that it was unused.
    The code I wrote here is therefore unused as well, so it is commented out.
    I did not delete it, because it may be useful later on.

compiler/direct_arg_in_out.m:
    Don't make and split var_tables, since it is no longer needed.

compiler/accumulator.m:
compiler/add_class.m:
compiler/add_clause.m:
compiler/add_heap_ops.m:
compiler/add_pred.m:
compiler/add_special_pred.m:
compiler/add_trail_ops.m:
compiler/arg_info.m:
compiler/build_mode_constraints.m:
compiler/bytecode_gen.m:
compiler/check_typeclass.m:
compiler/clause_to_proc.m:
compiler/closure_analysis.m:
compiler/code_gen.m:
compiler/code_loc_dep.m:
compiler/complexity.m:
compiler/continuation_info.m:
compiler/cse_detection.m:
compiler/ctgc.livedata.m:
compiler/deep_profiling.m:
compiler/default_func_mode.m:
compiler/deforest.m:
compiler/delay_construct.m:
compiler/delay_partial_inst.m:
compiler/dep_par_conj.m:
compiler/det_analysis.m:
compiler/det_report.m:
compiler/distance_granularity.m:
compiler/equiv_type_hlds.m:
compiler/exception_analysis.m:
compiler/float_regs.m:
compiler/follow_code.m:
compiler/goal_mode.m:
compiler/goal_path.m:
compiler/higher_order.m:
compiler/hlds_out_pred.m:
compiler/hlds_rtti.m:
compiler/hlds_statistics.m:
compiler/inlining.m:
compiler/intermod.m:
compiler/intermod_analysis.m:
compiler/introduce_exists_casts.m:
compiler/introduce_parallelism.m:
compiler/lambda.m:
compiler/lco.m:
compiler/live_vars.m:
compiler/liveness.m:
compiler/loop_inv.m:
compiler/mark_tail_calls.m:
compiler/ml_accurate_gc.m:
compiler/ml_args_util.m:
compiler/ml_closure_gen.m:
compiler/ml_gen_info.m:
compiler/ml_proc_gen.m:
compiler/mode_errors.m:
compiler/mode_info.m:
compiler/modecheck_goal.m:
compiler/par_loop_control.m:
compiler/pd_debug.m:
compiler/pd_info.m:
compiler/pd_util.m:
compiler/polymorphism_info.m:
compiler/post_typecheck.m:
compiler/proc_gen.m:
compiler/proc_requests.m:
compiler/purity.m:
compiler/push_goals_together.m:
compiler/quantification.m:
compiler/rbmm.add_rbmm_goal_infos.m:
compiler/rbmm.live_variable_analysis.m:
compiler/rbmm.points_to_analysis.m:
compiler/rbmm.points_to_graph.m:
compiler/rbmm.points_to_info.m:
compiler/rbmm.region_liveness_info.m:
compiler/rbmm.region_transformation.m:
compiler/recompute_instmap_deltas.m:
compiler/saved_vars.m:
compiler/simplify_goal_unify.m:
compiler/simplify_info.m:
compiler/simplify_proc.m:
compiler/size_prof.m:
compiler/ssdebug.m:
compiler/stack_alloc.m:
compiler/stack_layout.m:
compiler/stack_opt.m:
compiler/stm_expand.m:
compiler/store_alloc.m:
compiler/structure_reuse.analysis.m:
compiler/structure_reuse.direct.choose_reuse.m:
compiler/structure_reuse.direct.detect_garbage.m:
compiler/structure_reuse.domain.m:
compiler/structure_reuse.indirect.m:
compiler/structure_reuse.lbu.m:
compiler/structure_reuse.lfu.m:
compiler/structure_reuse.versions.m:
compiler/structure_sharing.analysis.m:
compiler/structure_sharing.domain.m:
compiler/switch_detection.m:
compiler/table_gen.m:
compiler/tabling_analysis.m:
compiler/term_constr_build.m:
compiler/term_constr_initial.m:
compiler/term_errors.m:
compiler/term_pass1.m:
compiler/term_pass2.m:
compiler/trace_gen.m:
compiler/trailing_analysis.m:
compiler/try_expand.m:
compiler/tupling.m:
compiler/unneeded_code.m:
compiler/untupling.m:
compiler/unused_args.m:
compiler/unused_imports.m:
    Conform to the changes above. Mostly this means

    - not passing a module_info to get a var_table out of a proc_info, but
    - having to pass a module_info to code that either constructs a var_table,
      or adds entries to a var_table (since we now need the type table
      to figure out whether variables' types are dummies).
2022-08-18 18:53:15 +10:00
Zoltan Somogyi
9ba0dca846 Describe pred_origins separarely for users & devs.
compiler/pred_name.m:
    Replace pred_info_id_to_string, which was intended to generate ids
    of predicates for both users and developers, with two predicates,
    pred_origin_to_{user,dev}_string, that each target only one audience.
    The version for developers includes all the details that compiler
    developers may need, while the version for users does not, since
    it is just useless clutter from their point view.

    The new versions also take only a pred_origin as input, not the whole
    pred_info containing the pred_origin. This is needed, because for
    the base predicate whose transformation a pred_origin may record,
    we have *only* its pred_origin, not its pred_info.

    Record more information for some pred_origins. Record the promise type
    for predicates created for assertions (which we can longer look up
    in the pred_info). And record the file name and line number of
    initialise and finalise declarations, since a development wouldn't like
    being told "this is a predicate that implements an initialise declaration"
    if the module contained more than one, and the difference actually
    mattered.

    Switch from record pred_form arities to user arities for the pred_origins
    of tabling aux predicates, for consistency with other pred_origins.

compiler/hlds_out_util.m:
    Make the corresponding changes to the functions that used to call
    pred_info_id_to_string.

    Use pred_origin_to_dev_string to identify procedures that some cons_ids
    can refer to, since those cons_ids can appear only in compiler-generated
    code, which is of interest only to developers.

compiler/prog_item.m:
    Switch from record pred_form arities to user arities for the parse_tree
    version of pred_origins of tabling aux predicates.

compiler/prog_out.m:
    Provide versions of some functions that do not put quotes around
    the sym_names when converting them to strings. The
    pred_origin_to_dev_string does not want quotes, because our use of
    unmatched quotes `' can screw up syntax highlighting in HLDS dumps.

compiler/accumulator.m:
compiler/add_clause.m:
compiler/add_pragma_tabling.m:
compiler/add_pred.m:
compiler/cse_detection.m:
compiler/dead_proc_elim.m:
compiler/deep_profiling.m:
compiler/det_analysis.m:
compiler/hlds_out_goal.m:
compiler/hlds_out_module.m:
compiler/hlds_out_pred.m:
compiler/implementation_defined_literals.m:
compiler/make_hlds_passes.m:
compiler/mercury_compile_llds_back_end.m:
compiler/mode_errors.m:
compiler/modes.m:
compiler/par_conj_gen.m:
compiler/passes_aux.m:
compiler/pd_debug.m:
compiler/proc_gen.m:
compiler/purity.m:
compiler/structure_reuse.analysis.m:
compiler/structure_reuse.domain.m:
compiler/structure_reuse.indirect.m:
compiler/structure_sharing.analysis.m:
compiler/term_constr_build.m:
compiler/term_constr_data.m:
compiler/term_constr_fixpoint.m:
compiler/term_constr_pass2.m:
compiler/term_constr_util.m:
compiler/tupling.m:
compiler/unused_args.m:
    Conform to the changes above.
2022-07-25 13:54:38 +10:00
Zoltan Somogyi
4c9d04434a Classify pred_names into four categories.
compiler/pred_name.m:
    Group pred_origins into four categories, giving each category its own
    function symbol. The categories are

    - predicates that contain, or may contain, code directly written
      by the user;
    - predicates created wholly by the compiler,
    - predicates created by the compiler by transforming a predicate, and
    - predicates created by the compiler by transforming a procedure.

    We distinguish between the first two because we want to report
    errors only in user-written code, since reporting an error that
    the user is powerless to fix is not a good idea.

    We distinguish between the last two just to allow us to store
    the proc_id of the transformed procedure next to its pred_id.

compiler/higher_order.m:
    Replace a boolean with value of a bespoke type.

    Rename some predicates to avoid ambiguity.

compiler/*.m:
    Conform to the changes above.
2022-07-23 09:28:40 +10:00
Zoltan Somogyi
08365979d0 Move pred_name.m to the HLDS package.
This is so that it can become the home of the type currently named
pred_origin in hlds_pred.m, which (after being given new name) will become
a structured representation of predicate names.

The only thing that kept pred_name.m in the parse_tree package was the fact
that parse_pragma.m, which has no access to the hlds package, called it
to create the name of a type-specialized predicate when parsing
type_spec pragmas. The main part of this diff, apart from the trivial
updates to import hlds.pred_name instead parse_tree.pred_name, deals
with this issue.

The problem is how to ensure that the compiler invocations that create
type-specialized predicates (invocations that compile the module containing
the type_spec pragma that calls for this) and the invocations that create
the calls to those predicates (invocations that mostly compile other modules)
agree on the name of the name of the type-specialized predicate.

The old approach was this.

    When reading in (say) mod1.m which contains a type_spec pragma,
    we construct the name of the type-specialized predicate from

    - the name of the module (mod1),
    - the name of the predicate to be specialized, and
    - the type substitution in the pragma.

    We then record this name in the pragma.

    If the compiler invocation generates code, we use this name in the
    predicate definition. If the compiler invocation creates a .int file,
    we record the name in the third argument of the type_spec pragma.
    This third argument is NOT allowed to exist in .m files.

    Other compiler invocations that read in mod1.int when compiling
    another module, e.g. mod2.m, use the specialized name in the third argument
    of the type_spec pragma as the name to use in calls.

In this approach, the single-source-of-truth about the name of the
type-specialized predicate is the name constructed when parsing mod1.m,
which is conveyed to compiler invocations on other modules through
the third argument of the type_spec pragma.

The new approach is this:

    When reading in (say) mod1.m which contains a type_spec pragma,
    we give guaranteed-to-be-unique names to all the anonymous variables
    in the type_spec pragma. We also record in the type_spec pragma
    the name of the module whose (source or interface) file we read
    the pragma from. The name of the predicate to be specialized
    was of course already in the pragma.

    If the compiler invocation generates code, we construct the name
    of the type-specialized version of the predicate when we add the
    all-tvars-are-named type_spec pragma to the HLDS. If the compiler
    invocation creates a .int file, we write out the all-tvars-are-named
    version of the type_spec pragma. The pragma also contains the predicate
    name to be specialized. It does not contain the name of the module,
    but we will write out type_spec pragmas from module_x.m *only* to
    module_x.int, never to any other .int file, so any readers of
    the type_spec pragma from mod1.int will also know the name of the
    module that the pragma came from.

    Other compiler invocations that read in mod1.int when compiling
    another module, e.g. mod2.m, therefore get exactly the same

    - module name,
    - the name of the predicate to be specialized, and
    - the type substitution in the pragma

    as the compiler invocations on mod1.m. The module name are the
    predicate name are never changed by being written out and then
    read back in, and *due to the explicit names given to any formerly
    anonymous variables*, the type substitution is changed by this either.
    This means that the compiler invocations on mod1.m and mod2.m
    give the same parameters to the same function, and therefore they are
    guaranteed to get the same string as the name of the type-specialized
    version of the predicate.

In this approach, the single-source-of-truth about the name of the
type-specialized predicate is the function constructing that name
and its inputs.

compiler/hlds.m:
compiler/parse_tree.m:
compiler/pred_name.m:
    Move pred_name.m from the parse_tree package to the hlds package.

compiler/prog_item.m:
    Change the representation of type_spec pragmas to

    - delete the name of the specialized predicate, and replace it with
    - the name of the module the pragma was read in from.

compiler/parse_pragma.m:
    Delete the code for parsing the third argument of type_spec pragmas.
    Allow them to exist for a short transition period, but ignore them.
    (If we read in files containing them, the result will be a link error
    if the type substitution contains anonymous variables. In that case,
    a rebuild of the program with all modules compiled using the *same
    compiler version* will work.)

    Give guaranteed-to-be-unique names to all anonymous type variable
    in the type substitution part of the type_spec pragma we construct.

compiler/add_pragma_type_spec.m:
    Construct the name of the type-specialized predicate as the type_spec
    pragma is added to the HLDS.

compiler/parse_tree_out_pragma.m:
    Never write out a type_spec par_loop_control with a third argument.

    Delete the var_name_print argument of the predicate that writes out
    type_spec pragmas. Instead, *always* use print_name_only.

compiler/options.m:
    Add a way of testing whether the installed compiler has this change.

compiler/accumulator.m:
compiler/add_pragma_tabling.m:
compiler/add_special_pred.m:
compiler/base_typeclass_info.m:
compiler/check_typeclass.m:
compiler/dep_par_conj.m:
compiler/distance_granularity.m:
compiler/higher_order.m:
compiler/hlds_code_util.m:
compiler/intermod.m:
compiler/lambda.m:
compiler/layout_out.m:
compiler/lco.m:
compiler/loop_inv.m:
compiler/make_hlds_passes.m:
compiler/name_mangle.m:
compiler/opt_debug.m:
compiler/opt_util.m:
compiler/par_loop_control.m:
compiler/parse_tree_out.m:
compiler/pd_info.m:
compiler/prog_rep.m:
compiler/ssdebug.m:
compiler/stm_expand.m:
compiler/structure_reuse.versions.m:
compiler/table_gen.m:
compiler/tupling.m:
compiler/untupling.m:
compiler/unused_args.m:
2022-07-20 21:33:09 +10:00
Zoltan Somogyi
af196031ea Move pred_origin towards a structured pred_name.
compiler/hlds_pred.m:
    Add a long comment about using pred_origin as a structured pred name.

    Delete the origin_created pred_origin with origin_deforestation,
    which was one of two ways that the compiler could create new predicates
    that weren't derived from one existing predicate, procedure, or other
    single Mercury construct. (Deforestation picks a conjunction of two
    or more goals, and created a new predicate out of *them*.)
    Replace the other, created_by_io_tabling, with a pred_transformation,
    since in that case, the new predicate *is* derived from a single
    existing predicate.

    Add a mechanism for recording the predicates created by the distance
    granularity transformation, which previously was recorded in the predicate
    name, but not in the pred_origin.

    Deleted the dnf predicate transform, since it hasn't been used
    since the Aditi backend was deleted in 2006.

    Include the pred_or_func distinction, and the original user arity,
    in the pred_origin of user defined predicates and functions.

    Include in most other pred transformations the parameters that are
    now recorded in the corresponding transform_name used in pred_name.m,
    with the exception of the pred_or_func distinction, since it is now
    available by following the chain of transforms to the base pred_origin,
    which should include that info.

    Use a type_ctor, not its components, in a pred origin.

    Shorten the too-long names of some function symbols.

compiler/distance_granularity.m:
    Record the transform done by this module.

    Use state variables where appropriate.

    Use more consistent variable names.

    Eliminate excessive indentation in the example transformation
    in the module introduction comment.

compiler/loop_inv.m:
    Fix a bug. The sequence number field of the transform_name
    was being filled with something other than a sequence number,
    which could be the same for two transformations. (Or at least,
    I have seen no convincing argument for why they couldn't be.
    If such an argument existed, the sequence number field would
    not be needed, so the old code would still have been wrong,
    just for a different reason :-)

    Rename a predicate to avoid ambiguity.

compiler/hlds_module.m:
    Add the per-context counter needed by the new code in loop_inv.m.

compiler/pd_info.m:
    The predicate that defines a new predicate always specifies
    the transform_name as tn_deforestation, so don't leave it up
    to the caller to specify the pred_origin of the new predicate;
    instead, construct it here as a deforestation transform of the
    base predicate. That is the origin argument that our one caller
    always specified anyway.

compiler/purity.m:
    Use a full switch over pred_origins, not a partial one,
    to make a decision.

compiler/accumulator.m:
compiler/add_clause.m:
compiler/add_foreign_proc.m:
compiler/add_pragma_tabling.m:
compiler/add_pragma_type_spec.m:
compiler/add_pred.m:
compiler/add_solver.m:
compiler/deforest.m:
compiler/dep_par_conj.m:
compiler/higher_order.m:
compiler/hlds_defns.m:
compiler/hlds_out_pred.m:
compiler/hlds_out_util.m:
compiler/inlining.m:
compiler/layout_out.m:
compiler/lco.m:
compiler/mode_errors.m:
compiler/par_loop_control.m:
compiler/polymorphism.m:
compiler/prog_item.m:
compiler/ssdebug.m:
compiler/table_gen.m:
compiler/trace_params.m:
compiler/tupling.m:
compiler/untupling.m:
compiler/unused_args.m:
compiler/xml_documentation.m:
    Conform to the changes above.
2022-07-20 01:05:34 +10:00
Zoltan Somogyi
8122e83d2a Record typechecking results in var_tables.
compiler/hlds_clauses.m:
    The clauses_info type used to have two fields whose type is "vartypes".
    One contained type information we knew before typechecking, e.g. from
    explicit "Var : type" annotations, while the other contained the
    *results* of typechecking. Keep the former, but replace the latter
    with a var_table.

    Allow compiler passes that construct clauses to fill in the first field
    with the types of the head variables, because for the clauses of some
    kinds of predicates (such as predicates implementing builtins) that are
    "constructed correct" and do not need typechecking, this is all we need.

    Put the fields of clauses_info that deal with variables and their types
    next to each other, in the order in which they are filled in.

compiler/add_clause.m:
    Don't construct the context pieces needed for parsing mode annotations
    on arguments in the clause head unless the clause head's arguments
    *have* mode annotations, which they virtually never do.

compiler/add_pred.m:
compiler/add_special_pred.m:
    Put the types of the head variables into the var_table in the clauses_info
    we create for clauses for builtin predicates and unify/compare/index
    predicates respectively, for use by unused_imports.m.

compiler/typecheck.m:
    Fill in the var_table field in

    - predicates we have typechecked,
    - predicates for which we have created stub clauses that are
      "born type-correct", and
    - predicates for class methods whose code will be created later,
      during the polymorphism pass.

    In the last case, we fill in only the types of the head variables,
    preserving old behavior.

    Give some predicates more meaningful names. Inline a predicate at its
    only call site.

compiler/post_typecheck.m:
    Switch to using the var_tables computed by typechecking.

    Reset varsets in clauses_infos to empty, to tell hlds_out_pred.m
    not use it as the source of variable name info.

compiler/hlds_pred.m:
    Provide functionality to record the types of head variables
    in both vartypes and in var_tables.

compiler/hlds_out_pred.m:
    Get information about variable names from either the clauses_info's
    varset field (if the varset is nonempty, not yet having been reset
    by post_typecheck.m), or from its var_table field (if the varset
    *has* been reset to empty).

    Likewise, get information about variable types from either the
    clauses_info's var_table field (if it is not empty, having been filled in
    either by typechecking or by code created the type clauses "type-correct"
    at the start), or from its explicit_vartypes field (if the var_table field
    has not yet been filled in).

    It is possible that in the future, we may want to dump out the
    contents of the explicit_vartypes field even if the var_table
    has also been filled in. However, since the old code of write_pred
    had no such functionality, the chance we will need that in the future
    is small, and we can deal with it when the issue does arise.

compiler/goal_path.m:
compiler/hlds_out_goal.m:
compiler/intermod.m:
compiler/unify_proc.m:
    Convert these modules to use var_tables.

compiler/prog_type.m:
compiler/type_util.m:
    Record the fact that the builtin type "store_at_ref_type" is not a dummy
    type. Without this special-casing, the creation of a var_table containing
    a variable of this type would crash the compiler, because

    - unlike other builtin types, this one *has* a definition, in
      private_builtin.m, but
    - since it is a builtin type, its "definition" in the type table
      has no representation information, so the code of is_type_a_dummy
      cannot tell if that "definition" is a dummy or not.

compiler/prog_util.m:
    Provide the var_table equivalent of an existing utility predicate
    for varsets.

compiler/qual_info.m:
    Give a field of the qual_info type a more meaningful name.

compiler/typecheck_errors.m:
    Fix argument order and variable names.

compiler/vartypes.m:
compiler/var_table.m:
    Add a predicate to check whether a variable has a user-given name.

    Replace the varset_vartypes type in vartypes.m with the type_qual type
    in var_table.m, which uses var_tables, since its user, hlds_out_goal.m,
    has been converted to use var_tables. (Most variables of this type
    have been named TypeQual, which is why the type now has that name.)

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

    Export the definition of the inst_graph_info type, instead of exporting
    a getter and a setter for every one of its fields.

compiler/higher_order.m:
    Conform to the changes above, by calling clauses_info_init,
    instead of repeating its code here.

compiler/accumulator.m:
compiler/add_foreign_proc.m:
compiler/add_pragma_type_spec.m:
compiler/build_mode_constraints.m:
compiler/check_promise.m:
compiler/clause_to_proc.m:
compiler/format_call.m:
compiler/hhf.m:
compiler/instance_method_clauses.m:
compiler/lambda.m:
compiler/mode_constraints.m:
compiler/old_type_constraints.m:
compiler/par_loop_control.m:
compiler/polymorphism.m:
compiler/polymorphism_info.m:
compiler/prop_mode_constraints.m:
compiler/purity.m:
compiler/stm_expand.m:
compiler/structure_reuse.versions.m:
compiler/table_gen.m:
    Conform to the changes above.

tests/invalid/illtyped_compare.err_exp:
    Expect an improved variable name from unify_proc.m.

tests/invalid/try_detism.err_exp:
    Expect a different variable number for an unnamed variable.
2022-05-29 15:22:16 +10:00
Zoltan Somogyi
404fea1bd2 Start removing non-var_table versions of predicates.
compiler/arg_info.m:
compiler/goal_util.m:
compiler/hlds_rtti.m:
compiler/instmap.m:
compiler/recompute_instmap_deltas.m:
compiler/type_util.m:
    For predicates which had both varset/vartypes and var_table versions,
    but the former is not used anymore because all its callers have been
    switched to the latter,

    - delete the former, and
    - rename the latter to the name of the former.

    In goal_util.m, switch two currently-unused predicates to use var_tables
    instead of varsets/vartypes, in case they are needed again.

compiler/hlds_pred.m:
    Likewise replace define_new_pred with define_new_pred_vt, but also
    change its implementation to use var_table for everything except
    the final construction of the proc_info.

compiler/accumulator.m:
compiler/call_gen.m:
compiler/code_loc_dep.m:
compiler/constraint.m:
compiler/deforest.m:
compiler/delay_construct.m:
compiler/dep_par_conj.m:
compiler/det_analysis.m:
compiler/det_util.m:
compiler/float_regs.m:
compiler/follow_code.m:
compiler/higher_order.m:
compiler/interval.m:
compiler/lambda.m:
compiler/lco.m:
compiler/live_vars.m:
compiler/liveness.m:
compiler/loop_inv.m:
compiler/ml_code_gen.m:
compiler/modes.m:
compiler/pd_info.m:
compiler/pd_util.m:
compiler/push_goals_together.m:
compiler/rbmm.region_liveness_info.m:
compiler/saved_vars.m:
compiler/simplify_goal.m:
compiler/simplify_proc.m:
compiler/size_prof.m:
compiler/ssdebug.m:
compiler/structure_reuse.indirect.m:
compiler/structure_reuse.lbu.m:
compiler/structure_reuse.lfu.m:
compiler/table_gen.m:
compiler/tupling.m:
compiler/unneeded_code.m:
compiler/untupling.m:
    Conform to the changes above.
2022-05-15 21:40:10 +10:00
Zoltan Somogyi
c9249d0b78 Convert more passes to use var_tables.
compiler/accumulator.m:
compiler/trailing_analysis.m:
compiler/unneeded_code.m:
compiler/unused_args.m:
    Convert these passes to use var_tables.

compiler/goal_store.m:
    Convert this auxiliary module of accumulator.m to use var_tables.

    Convert a non-tail-recursive function to a tail-recursive predicate
    by using an accumulator.

    Improve argument order.

compiler/goal_util.m:
    Convert the parts of this module that serve goal_store.m
    to use var_tables.
2022-04-19 15:24:34 +10:00
Zoltan Somogyi
ea4f95a7ed Use var_tables in lco.m, and when dumping goals.
Since this is the first converted module that dumps out goals when
debugging trace flags are enabled, this required generalizing the code
that does that, to take either varsets or var_tables as a means of
specifying the names of variables. We do this via a new type,
var_name_source, which contains either a varset or a var_table.

Almost all of this diff is there to implement this generalization.
A large part of it affects code in the parse_tree package that we use
to write out the parts of HLDS goals that are defined by types defined
in that package. Since we want to avoid making any part of the parse_tree
package dependent on the hlds package, this required defining the
var_name_source type in the parse_tree package, which in turn requires
var_table.m to be in that same package.

compiler/lco.m:
    Convert this module to use var_tables instead of varsets and vartypes.

compiler/var_table.m:
    Move this module from the hlds package to the parse_tree package.

    To make this, possible, move the parts that required access to the HLDS
    to hlds_pred.m, from where it was usually invoked.

    Export some utility predicates to allow the moved code to work
    in hlds_pred.m without access to the actual definition of the
    var_table type.

    Define the var_name_source type.

    Add some utility functions for use by code writing out variable names.

compiler/hlds_pred.m:
    Add the code moved from var_table.m.

compiler/vartypes.m:
    Move this module from the hlds package to the parse_tree package,
    for symmetry with var_table.m. It did not depend on being in hlds
    in any way.

compiler/hlds.m:
compiler/parse_tree.m:
    Move vartypes.m and var_table.m from the hlds package
    to the parse_tree package.

compiler/hlds_out_goal.m:
    Change all the predicates in this module to take a var_name_source
    instead of a prog_varset.

    Fix some comments.

compiler/hlds_out_util.m:
    Change some of the predicates in this module (those called from
    hlds_out_goal.m) to take a var_name_source instead of a prog_varset.

compiler/parse_tree_out_term.m:
    Provide variants of some existing predicates and functions that take
    var_name_sources instead of varsets. The code of the copies
    duplicates the logic of the originals, though I hope that this
    duplication can be done away with at the end of the transition.
    (The best solution would be to use a typeclass with methods
    that convert vars to their names, but we would want to ensure
    that the compiler can specialize all the affected predicates
    and functions to the two instances of this typeclass, which is
    something that we cannot do yet. In the meantime, the lack of
    any generalization in the old versions preserves their performance.)

tools/sort_imports:
tools/filter_sort_imports:
    A new tool that automatically sorts any occurrences of consecutive
    ":- import_module" declarations in the named files. The sorting is done
    in filter_sort_imports; sort_imports loops over the named files.

    After automatically replacing all occurrences of hlds.{vartypes,var_table}
    in import_module declarations with their parse_tree versions, the updated
    import_module declarations were usually out of order with respect to
    their neighbours. I used this script to fix that, and some earlier
    out-of-order imports.

compiler/accumulator.m:
compiler/add_class.m:
compiler/add_clause.m:
compiler/add_foreign_proc.m:
compiler/add_heap_ops.m:
compiler/add_pragma_type_spec.m:
compiler/add_pred.m:
compiler/add_trail_ops.m:
compiler/analysis.m:
compiler/arg_info.m:
compiler/build_mode_constraints.m:
compiler/bytecode_gen.m:
compiler/call_gen.m:
compiler/check_promise.m:
compiler/closure_analysis.m:
compiler/closure_gen.m:
compiler/code_info.m:
compiler/code_loc_dep.m:
compiler/common.m:
compiler/compile_target_code.m:
compiler/complexity.m:
compiler/const_prop.m:
compiler/constraint.m:
compiler/continuation_info.m:
compiler/convert_parse_tree.m:
compiler/coverage_profiling.m:
compiler/cse_detection.m:
compiler/ctgc.datastruct.m:
compiler/ctgc.util.m:
compiler/dead_proc_elim.m:
compiler/deep_profiling.m:
compiler/deforest.m:
compiler/delay_construct.m:
compiler/delay_partial_inst.m:
compiler/dep_par_conj.m:
compiler/det_analysis.m:
compiler/det_report.m:
compiler/det_util.m:
compiler/direct_arg_in_out.m:
compiler/disj_gen.m:
compiler/distance_granularity.m:
compiler/equiv_type_hlds.m:
compiler/exception_analysis.m:
compiler/file_names.m:
compiler/float_regs.m:
compiler/follow_vars.m:
compiler/format_call.m:
compiler/generate_dep_d_files.m:
compiler/get_dependencies.m:
compiler/goal_expr_to_goal.m:
compiler/goal_mode.m:
compiler/goal_path.m:
compiler/goal_store.m:
compiler/goal_util.m:
compiler/granularity.m:
compiler/hhf.m:
compiler/higher_order.m:
compiler/hlds_clauses.m:
compiler/hlds_code_util.m:
compiler/hlds_error_util.m:
compiler/hlds_goal.m:
compiler/hlds_llds.m:
compiler/hlds_out_pred.m:
compiler/hlds_rtti.m:
compiler/hlds_statistics.m:
compiler/inlining.m:
compiler/inst_check.m:
compiler/inst_test.m:
compiler/inst_user.m:
compiler/instance_method_clauses.m:
compiler/instmap.m:
compiler/intermod.m:
compiler/intermod_analysis.m:
compiler/interval.m:
compiler/introduce_exists_casts.m:
compiler/introduce_parallelism.m:
compiler/item_util.m:
compiler/lambda.m:
compiler/live_vars.m:
compiler/liveness.m:
compiler/llds.m:
compiler/llds_out_data.m:
compiler/llds_out_file.m:
compiler/llds_out_util.m:
compiler/lookup_switch.m:
compiler/loop_inv.m:
compiler/make.module_target.m:
compiler/make.util.m:
compiler/make_goal.m:
compiler/make_hlds_separate_items.m:
compiler/make_hlds_types.m:
compiler/mark_tail_calls.m:
compiler/mercury_compile_mlds_back_end.m:
compiler/middle_rec.m:
compiler/ml_accurate_gc.m:
compiler/ml_args_util.m:
compiler/ml_call_gen.m:
compiler/ml_closure_gen.m:
compiler/ml_code_gen.m:
compiler/ml_code_util.m:
compiler/ml_commit_gen.m:
compiler/ml_disj_gen.m:
compiler/ml_foreign_proc_gen.m:
compiler/ml_gen_info.m:
compiler/ml_lookup_switch.m:
compiler/ml_proc_gen.m:
compiler/ml_simplify_switch.m:
compiler/ml_switch_gen.m:
compiler/ml_tag_switch.m:
compiler/ml_unify_gen.m:
compiler/ml_unify_gen_construct.m:
compiler/ml_unify_gen_deconstruct.m:
compiler/ml_unify_gen_test.m:
compiler/ml_unify_gen_util.m:
compiler/mlds_to_c_data.m:
compiler/mlds_to_c_func.m:
compiler/mlds_to_c_global.m:
compiler/mlds_to_cs_class.m:
compiler/mlds_to_cs_file.m:
compiler/mlds_to_java_data.m:
compiler/mlds_to_java_file.m:
compiler/mlds_to_java_stmt.m:
compiler/mlds_to_java_type.m:
compiler/mmc_analysis.m:
compiler/mode_comparison.m:
compiler/mode_constraints.m:
compiler/mode_debug.m:
compiler/mode_errors.m:
compiler/mode_info.m:
compiler/mode_ordering.m:
compiler/modecheck_call.m:
compiler/modecheck_coerce.m:
compiler/modecheck_goal.m:
compiler/modecheck_unify.m:
compiler/modecheck_util.m:
compiler/modes.m:
compiler/module_cmds.m:
compiler/old_type_constraints.m:
compiler/opt_debug.m:
compiler/optimize.m:
compiler/options_file.m:
compiler/ordering_mode_constraints.m:
compiler/par_loop_control.m:
compiler/parse_item.m:
compiler/parse_string_format.m:
compiler/parse_tree_out_inst.m:
compiler/parse_tree_to_term.m:
compiler/parse_util.m:
compiler/pd_debug.m:
compiler/pd_info.m:
compiler/pd_util.m:
compiler/peephole.m:
compiler/polymorphism.m:
compiler/polymorphism_info.m:
compiler/polymorphism_lambda.m:
compiler/polymorphism_type_class_info.m:
compiler/polymorphism_type_info.m:
compiler/post_typecheck.m:
compiler/pragma_c_gen.m:
compiler/pred_name.m:
compiler/pred_table.m:
compiler/prog_item.m:
compiler/prog_rep.m:
compiler/prop_mode_constraints.m:
compiler/purity.m:
compiler/push_goals_together.m:
compiler/qual_info.m:
compiler/quantification.m:
compiler/rbmm.execution_path.m:
compiler/rbmm.m:
compiler/rbmm.points_to_analysis.m:
compiler/rbmm.points_to_graph.m:
compiler/rbmm.points_to_info.m:
compiler/rbmm.region_resurrection_renaming.m:
compiler/rbmm.region_transformation.m:
compiler/recompilation.used_file.m:
compiler/recompilation.version.m:
compiler/recompute_instmap_deltas.m:
compiler/resolve_unify_functor.m:
compiler/rtti.m:
compiler/rtti_out.m:
compiler/rtti_to_mlds.m:
compiler/saved_vars.m:
compiler/set_of_var.m:
compiler/simplify_goal_call.m:
compiler/simplify_goal_conj.m:
compiler/simplify_goal_disj.m:
compiler/simplify_goal_ite.m:
compiler/simplify_goal_scope.m:
compiler/simplify_goal_switch.m:
compiler/simplify_goal_unify.m:
compiler/simplify_info.m:
compiler/simplify_proc.m:
compiler/size_prof.m:
compiler/smm_common.m:
compiler/ssdebug.m:
compiler/stack_alloc.m:
compiler/stack_layout.m:
compiler/stack_opt.m:
compiler/stm_expand.m:
compiler/store_alloc.m:
compiler/structure_reuse.analysis.m:
compiler/structure_reuse.direct.choose_reuse.m:
compiler/structure_reuse.direct.detect_garbage.m:
compiler/structure_reuse.domain.m:
compiler/structure_reuse.indirect.m:
compiler/structure_reuse.lbu.m:
compiler/structure_reuse.lfu.m:
compiler/structure_sharing.analysis.m:
compiler/structure_sharing.domain.m:
compiler/superhomogeneous.m:
compiler/switch_detection.m:
compiler/switch_gen.m:
compiler/switch_util.m:
compiler/table_gen.m:
compiler/tabling_analysis.m:
compiler/term_constr_build.m:
compiler/term_constr_data.m:
compiler/term_constr_initial.m:
compiler/term_constr_main.m:
compiler/term_constr_main_types.m:
compiler/term_constr_util.m:
compiler/term_pass1.m:
compiler/term_traversal.m:
compiler/term_util.m:
compiler/trace_gen.m:
compiler/trailing_analysis.m:
compiler/transform_llds.m:
compiler/try_expand.m:
compiler/tupling.m:
compiler/type_assign.m:
compiler/type_ctor_info.m:
compiler/type_util.m:
compiler/typecheck.m:
compiler/typecheck_debug.m:
compiler/typecheck_errors.m:
compiler/typecheck_info.m:
compiler/unify_gen_construct.m:
compiler/unify_gen_deconstruct.m:
compiler/unify_proc.m:
compiler/unique_modes.m:
compiler/unneeded_code.m:
compiler/untupling.m:
compiler/unused_args.m:
compiler/unused_imports.m:
compiler/var_locn.m:
compiler/write_deps_file.m:
compiler/write_module_interface_files.m:
    Conform to the changes above.
2022-04-18 02:00:38 +10:00
Zoltan Somogyi
3f3045c9e2 Get and set varsets/vartypes in proc_infos together.
compiler/hlds_pred.m:
    We eventually want to replace the varset and vartypes fields in
    each proc_info with a var_table, but it is not practical to do so
    at once; it will have to be done gradually, a few modules at most
    at a time. During this process, we will need a way either

    - to let already converted modules get a var_table out of the proc_info,
      and put an updated var_table back into a proc_info, even though
      proc_infos still contain varset and vartypes fields, or

    - to let not-yet-converted modules get varsets and vartypes out of the
      proc_info, and put updated varsets and vartypes back into a proc_info,
      even though proc_infos already store a var_table.

    The latter cannot be done in two halves (i.e. set the varset half
    of the var_table, and then set its vartypes half), and while the former
    *can* be done that way, it is more efficient to do them at the same time.

    Therefore as a first step, this diff replaces the indiviual getter
    and setter predicates of the varset and vartypes fields of proc_info
    with a getter that gets both and a setter that sets both.

    Put the varset and vartypes next to each other in a structure.

compiler/code_info.m:
    Delete a function that duplicates a function in var_table.m.

    Conform to the change above.

compiler/det_report.m:
    Factor out some common code.

    Conform to the change above.

compiler/det_util.m:
    Delete a no-longer-needed predicate.

    Conform to the change above.

compiler/higher_order.m:
    Fix an old oversight: when deleting variables from the vartypes,
    delete them from the varset as well.

    Conform to the change above.

compiler/liveness.m:
    Avoid constructing and traversing a list unnecessarily.

    Conform to the change above.

compiler/accumulator.m:
compiler/add_heap_ops.m:
compiler/add_trail_ops.m:
compiler/arg_info.m:
compiler/build_mode_constraints.m:
compiler/bytecode_gen.m:
compiler/call_gen.m:
compiler/clause_to_proc.m:
compiler/closure_analysis.m:
compiler/code_gen.m:
compiler/code_loc_dep.m:
compiler/complexity.m:
compiler/continuation_info.m:
compiler/cse_detection.m:
compiler/ctgc.datastruct.m:
compiler/ctgc.util.m:
compiler/deep_profiling.m:
compiler/deforest.m:
compiler/delay_construct.m:
compiler/delay_partial_inst.m:
compiler/dep_par_conj.m:
compiler/det_analysis.m:
compiler/direct_arg_in_out.m:
compiler/disj_gen.m:
compiler/equiv_type_hlds.m:
compiler/exception_analysis.m:
compiler/float_regs.m:
compiler/follow_code.m:
compiler/goal_mode.m:
compiler/goal_path.m:
compiler/hlds_out_pred.m:
compiler/hlds_rtti.m:
compiler/hlds_statistics.m:
compiler/inlining.m:
compiler/intermod.m:
compiler/intermod_analysis.m:
compiler/introduce_exists_casts.m:
compiler/introduce_parallelism.m:
compiler/lambda.m:
compiler/lco.m:
compiler/live_vars.m:
compiler/loop_inv.m:
compiler/mark_tail_calls.m:
compiler/ml_accurate_gc.m:
compiler/ml_args_util.m:
compiler/ml_closure_gen.m:
compiler/ml_gen_info.m:
compiler/ml_proc_gen.m:
compiler/mode_info.m:
compiler/modecheck_goal.m:
compiler/modes.m:
compiler/par_loop_control.m:
compiler/pd_debug.m:
compiler/pd_info.m:
compiler/pd_util.m:
compiler/polymorphism_info.m:
compiler/proc_gen.m:
compiler/purity.m:
compiler/push_goals_together.m:
compiler/quantification.m:
compiler/rbmm.add_rbmm_goal_infos.m:
compiler/rbmm.live_variable_analysis.m:
compiler/rbmm.points_to_graph.m:
compiler/rbmm.points_to_info.m:
compiler/rbmm.region_liveness_info.m:
compiler/rbmm.region_transformation.m:
compiler/recompute_instmap_deltas.m:
compiler/saved_vars.m:
compiler/simplify_goal_unify.m:
compiler/simplify_info.m:
compiler/simplify_proc.m:
compiler/size_prof.m:
compiler/ssdebug.m:
compiler/stack_alloc.m:
compiler/stack_layout.m:
compiler/stack_opt.m:
compiler/stm_expand.m:
compiler/store_alloc.m:
compiler/structure_reuse.analysis.m:
compiler/structure_reuse.direct.choose_reuse.m:
compiler/structure_reuse.direct.detect_garbage.m:
compiler/structure_reuse.indirect.m:
compiler/structure_reuse.lbu.m:
compiler/structure_reuse.lfu.m:
compiler/structure_sharing.analysis.m:
compiler/structure_sharing.domain.m:
compiler/switch_detection.m:
compiler/table_gen.m:
compiler/tabling_analysis.m:
compiler/term_constr_build.m:
compiler/term_constr_initial.m:
compiler/term_errors.m:
compiler/term_pass1.m:
compiler/term_pass2.m:
compiler/trace_gen.m:
compiler/trailing_analysis.m:
compiler/try_expand.m:
compiler/tupling.m:
compiler/unneeded_code.m:
compiler/untupling.m:
compiler/unused_args.m:
compiler/unused_imports.m:
    Conform to the change above.
2022-04-07 21:22:21 +10:00
Zoltan Somogyi
9a9067171d Move more pred name creation to pred_name.m.
compiler/pred_name.m:
    Add two more pred name transforms: one used by I/O tabling,
    and one used by stm_expand.m.

    Change the names we generate for I/O tabling to fit in with our schemes,
    because we can (there is no part of the whole Mercury system that looks for
    the names we *used* to construct.

    Leave the names we generate for stm as they are, even though they also
    do not fit into our scheme, because changing them would obsolete
    the documentation (such as it is) in stm_expand.m.

    Return the name of instance predicates as strings, rather than
    as always-unqualified sym_names.

    Return the name of instance predicates and uci (unify, compare and index)
    predicates as strings, rather than as always-unqualified sym_names.

compiler/hlds_pred.m:
    Change the interface of the pred_info_create predicate to put the
    pred_or_func indication before the pred name. I did this originally
    to flush out places that constructed predicate names without
    going through pred_name.m. However, I also took the opportunity
    to fix an old issue, which was that

    - pred_info_create took in a sym_name to specify the name of the
      new predicate, but
    - it ignored the module name part of the sym_name, using a separately
      passed module name instead.

    This definitely violates the law of least astonishment.

    I change the interface of both pred_info_create and pred_info_init
    (which also had a similar issue, using the separately-passed module name
    only if the sym_name specifying the name was unqualified) to require
    their callers to decide the module name part of the name of the new pred,
    and pass it alongside the name that it qualifies. The changes to do this
    ended up being the bulk of the diff. (The define_new_pred predicate should
    also have this treatment applied to it, but that would have made the diff
    even larger.)

compiler/add_clause.m:
compiler/add_foreign_proc.m:
compiler/add_pragma_tabling.m:
compiler/add_pred.m:
    Conform to the changes above. Use variable names that distinguish
    raw names (strings) from sym_names.

    Require the sym_names in item_clause_infos, item_pred_decl_infos,
    item_mode_decl_infos, and various pragma_info_xyzs to be qualified.
    The parsing predicates that generate them implicitly qualify them
    if the name in the source code is unqualified.

    Delete the code that generated an error message when handed an
    item_pred_decl_info containing an unqualified sym_name. Due to
    the implicit quantification mentioned above, this can't happen.

    When adding foreign_procs to the HLDS, use the module name that
    came with the foreign_proc (which could have been explicit or implicit),
    *not* the name of the current module (which is what we used to use),
    when generating error messages. This difference could make the error
    message quite misleading. (We did not have a test case for this error
    message.)

compiler/add_pragma_type_spec.m:
    Conform to the changes above. Use variable names that distinguish
    raw names (strings) from sym_names.

    When adding adding type-specialized versions of predicates to the HLDS,
    use the module name that was created in parse_pragma.m; do not override
    it with the name of the module qualifier of the original predicate.
    If parse_pragma.m did its job right, the two should always be the same.

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

    Add an XXX for a questionable module qualifier we specify for a unify,
    compare or index predicate.

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

    Fix a variable version issue that caused progress messages to be
    printed at an unexpected time.

compiler/structure_reuse.versions.m:
    Conform to the changes above.

    Simplify the too-complex structure of the code that constructs
    predicate names.

compiler/accumulator.m:
compiler/check_typeclass.m:
compiler/dep_par_conj.m:
compiler/lambda.m:
compiler/par_loop_control.m:
compiler/stm_expand.m:
compiler/table_gen.m:
compiler/unused_args.m:
    Conform to the changes above.

compiler/make_hlds_error.m:
    Take the pred_or_func indicator before the predicate name.
    Use variable names that distinguish raw names (strings) from sym_names.

compiler/parse_util.m:
    Fix a missing undo of an nl_indent_delta.

compiler/foreign.m:
    Add a note about a predicate, that as far I can tell has not done
    anything useful for years, if not decades, is now unused. (This diff
    comments out the only call to it, in add_foreign_proc.m.) The only
    thing it *could* do was warn about a foreign_proc not being able
    to be implemented for the current target language, but that test
    in now done way earlier in the process, and foreign.m does not
    get called in any situation in which the message would be relevant.
2022-02-15 19:53:22 +11:00
Zoltan Somogyi
5750c35e64 Move pred-name-constructing code to pred_name.m.
compiler/pred_name.m:
    Support the construction of predicate names for more predicate transforms,
    including those done by higher_order.m and table_gen.m. Neither conformed
    to the naming scheme of the other predicate transformations. For the
    transforms done by higher_order.m, add XXXs noting this. For the transform
    done by table_gen.m, make it generate names that do conform to our pattern.
    We can do this because we only generate the affected predicates (and their
    names) in minimal model own stack grades, which are not operational :-(

    Move code to create names for the predicates implementing typeclass
    methods here.

    Move code to create names for unify, compare and index predicates here.

    Include "sym_name" in the names of the predicates that construct sym_names.

    Rename one of the existing transform_names to avoid ambiguity.

compiler/hlds_pred.m:
    Change the argument order of pred_info_init, partly to put first things
    first, but also to flush out places that construct predicate names.

compiler/add_special_pred.m:
compiler/check_typeclass.m:
compiler/hlds_code_util.m:
    Delete the code moved to pred_name.m.

compiler/accumulator.m:
compiler/add_pragma_type_spec.m:
compiler/add_pred.m:
compiler/base_typeclass_info.m:
compiler/dep_par_conj.m:
compiler/distance_granularity.m:
compiler/higher_order.m:
compiler/lambda.m:
compiler/layout_out.m:
compiler/loop_inv.m:
compiler/name_mangle.m:
compiler/opt_debug.m:
compiler/opt_util.m:
compiler/par_loop_control.m:
compiler/parse_pragma.m:
compiler/pd_info.m:
compiler/prog_rep.m:
compiler/special_pred.m:
compiler/structure_reuse.versions.m:
compiler/table_gen.m:
compiler/tupling.m:
compiler/untupling.m:
compiler/unused_args.m:
    Conform to the changes above.

tests/debugger/mmos_print.exp:
    Update the only minimal_model_own_stack generator predicate name
    outside the compiler.
2022-02-09 11:07:10 +11:00
Zoltan Somogyi
b80ba7095a Move to a unified scheme for pred name transforms.
compiler/pred_name.m:
    Put all the information needed to create a name for a transformed
    predicate or function into one data structure. This centralizes
    knowledge about the format of transformed names here, for the
    compiler components that use pred_name.m to construct new pred names.
    (Making all the *other* compiler components that now construct
    new pred names switch to use pred_names.m is future work.)

    This central data structure, transform_name, contains information
    that used to supplies using separate arguments, such as the initial
    prefix identifying the program transformation that creates the name,
    and an indication whether it is being applied to a predicate or a function.
    In cases where callers used to post-process the sym_name we return
    to add a procedure # as a suffix (to go after the suffix that pred_name.m
    adds to the name :-(), make such shenanigans unnecessary by making
    the proc_id number part of the transform_name.

    Replace the code that constructs lists of things (integers and
    substitutions for type vars) with shorter code, whose functionality
    is underdtandable at a glance. It is slower, but the construction
    of predicate names is rare it for that not to matter.

compiler/accumulator.m:
compiler/dep_par_conj.m:
compiler/distance_granularity.m:
compiler/lambda.m:
compiler/loop_inv.m:
compiler/par_loop_control.m:
compiler/parse_pragma.m:
compiler/pd_info.m:
compiler/structure_reuse.versions.m:
compiler/tupling.m:
compiler/untupling.m:
compiler/unused_args.m:
    Conform to the changes above.

    In pd_info.m, delete unneeded module qualifications on clause heads.

    In distance_granularity.m, delete code that duplicates code in pred_name.m.

    In structure_reuse.versions.m, delete an unhelpful type synonym.

    In several places, improve variable names.
2022-02-08 13:43:58 +11:00
Zoltan Somogyi
2eeeddaae0 Carve pred_name.m out of prog_util.m.
compiler/pred_name.m:
compiler/prog_util.m:
    As above.

compiler/notes/compiler_design.html:
    Document the new module.

compiler/accumulator.m:
compiler/dep_par_conj.m:
compiler/distance_granularity.m:
compiler/lambda.m:
compiler/loop_inv.m:
compiler/par_loop_control.m:
compiler/parse_pragma.m:
compiler/parse_tree.m:
compiler/pd_info.m:
compiler/structure_reuse.versions.m:
compiler/tupling.m:
compiler/untupling.m:
compiler/unused_args.m:
    Conform to the change above.
2022-02-08 06:30:34 +11:00
Zoltan Somogyi
a72627888e Make the goal_type type more fit for purpose.
compiler/hlds_pred.m:
    Separate out goal types that implement a promise from those that do not.
    Document the latter. (The former is documented elsewhere.)

    When creating a new predicate, require the caller to specify
    the goal type; do not supply a default that may be wrong.

    Give some predicates more meaningful names.

compiler/add_pred.m:
    When adding an implicit predicate declaration for a promise,
    specify that the new predicate is for a promise, instead of letting
    hlds_pred.m assume by default that it is NOT for a promise.

compiler/add_clause.m:
    When adding a clause to the HLDS, do not require callers to supply
    information that they cannot possibly know.

    Specify the goal_type for a promise when creating its predicate,
    not later.

compiler/pre_typecheck.m:
    Record the goal type of field access functions, whose Mercury definition
    we just created, as containing only Mercury code. Previously, we falsely
    recorded it as containing both Mercury clauses and foreign procs.

compiler/accumulator.m:
compiler/add_class.m:
compiler/add_foreign_proc.m:
compiler/add_mutable_aux_preds.m:
compiler/add_pragma_tabling.m:
compiler/add_pragma_type_spec.m:
compiler/add_special_pred.m:
compiler/check_promise.m:
compiler/check_typeclass.m:
compiler/intermod.m:
compiler/lambda.m:
compiler/make_hlds_passes.m:
compiler/par_loop_control.m:
compiler/purity.m:
compiler/stm_expand.m:
compiler/structure_reuse.versions.m:
compiler/table_gen.m:
compiler/typecheck.m:
compiler/untupling.m:
    Conform to the changes above.
2021-05-20 00:46:18 +10:00
Zoltan Somogyi
99334e8469 Switch to structured item sequence numbers.
compiler/prog_data.m:
    Define a data type that encodes the distinction between valid
    and dummy item sequence numbers in the type. Previously, different
    parts of the compiler expressed this distinction in two different ways,
    either using "-1" to represent a dummy sequence number, or using "no"
    in a maybe(int) type.

compiler/prog_item.m:
    Use the new type instead of plain "int" as the sequence number in items.

compiler/hlds_pred.m:
    Use the new type instead of plain "int" as the sequence number
    in cur_user_decl_infos. Document the fact that the presence of a
    cur_user_decl_info in a pred_info does NOT guarantee a valid
    item sequence number.

compiler/add_foreign_proc.m:
    When adding a foreign_proc to the HLDS, pass a whole item_pragma_info,
    not its components. (This change is what this diff started as, before
    the item_seq_num changes overwhelmed it.)

compiler/accumulator.m:
compiler/add_class.m:
compiler/add_clause.m:
compiler/add_mutable_aux_preds.m:
compiler/add_pragma.m:
compiler/add_pragma_tabling.m:
compiler/add_pred.m:
compiler/add_solver.m:
compiler/add_special_pred.m:
compiler/check_typeclass.m:
compiler/comp_unit_interface.m:
compiler/decide_type_repn.m:
compiler/default_func_mode.m:
compiler/hlds_clauses.m:
compiler/intermod.m:
compiler/item_util.m:
compiler/lambda.m:
compiler/make_hlds_passes.m:
compiler/par_loop_control.m:
compiler/parse_class.m:
compiler/parse_dcg_goal.m:
compiler/parse_inst_mode_defn.m:
compiler/parse_item.m:
compiler/parse_module.m:
compiler/parse_mutable.m:
compiler/parse_pragma.m:
compiler/parse_pragma_analysis.m:
compiler/parse_pragma_foreign.m:
compiler/parse_pragma_tabling.m:
compiler/parse_type_defn.m:
compiler/parse_type_repn.m:
compiler/parse_types.m:
compiler/proc_requests.m:
compiler/prog_mutable.m:
compiler/split_parse_tree_src.m:
compiler/stm_expand.m:
compiler/style_checks.m:
compiler/table_gen.m:
    Conform to the changes above.
2021-05-19 13:27:27 +10:00
Zoltan Somogyi
85eb971b8d Specify output streams in some places.
Besides this main purpose, this diff also replaces code that calls
io.write_string several times in a row with code that prints the
thing to be printed in one go with io.format.

compiler/accumulator.m:
compiler/code_gen.m:
compiler/dead_proc_elim.m:
compiler/interval.m:
compiler/ite_gen.m:
compiler/lco.m:
compiler/mode_debug.m:
compiler/mode_info.m:
compiler/modes.m:
compiler/stack_opt.m:
    As above.

compiler/Mercury.options:
    Specify --warn-implicit-stream-calls for the modules above,
    and for some other modules that are already free of such warnings.
2021-03-24 22:02:18 +11:00
Zoltan Somogyi
25b89ea8c6 Put bigger inputs first.
compiler/hlds_pred.m:
    Put a module_info input before a proc_info input.

compiler/*.m:
    Conform to the above.
2020-11-30 17:34:42 +11:00
Zoltan Somogyi
5f50259d16 Write to explicitly named streams in many modules.
Right now, most parts of the compiler write to the "current output stream".
This was a pragmatic choice at the time, but has not aged well. The problem
is that the answer to the question "where is the current output stream going?"
is not obvious in *all* places in the compiler (although it is obvious in
most). When using such implicit streams, finding where the output is going
to in a given predicate requires inspecting not just the ancestors of that
predicate, but also all their older siblings (since any of them could have
changed the current stream), *including* their entire call trees. This is
usually an infeasible task. By constrast, if we explicitly pass streams
to all output operations, we need only follow the places where the variable
representing that stream is bound, which the mode system makes easy.

This diff switches large parts of the compiler over to doing output only
to explicitly passed streams, never to the implicit "current output stream".
The parts it switches over are the parts that rely to a significant degree
on the innermost change, which is to the "output" typeclass in
parse_tree_out_info.m. This is the part that has to be switched over to
explicit streams first, because (a) many modules such as mercury_to_mercury.m
rely on the output typeclass, and (b) most other modules that do output
call predicates in these modules. Starting anywhere else would be like
building a skyscraper starting at the top.

This typeclass, output(U), has two instances: output(io), and output(string),
so you could output either to the current output stream, or to a string.
To allow the specification of the destination stream in the first case,
this diff changes the typeclass to output(S, U) with a functional dependency
from U to S, with the two instances being output(io.text_output_stream, io)
and output(unit, string). (The unit arg is ignored in the second case.)

There is a complication with the output typeclass method, add_list, that
outputs a list of items. The complication is that each item is output
by a predicate supplied by the caller, but the separator between the items
(usually a comma) is output by add_list itself. We don't want to give
callers of this method the opportunity to screw up by specifying (possibly
implicitly) two different output streams for these two purposes, so we want
(a) the caller to tell add_list where to put the separators, and then
(b) for add_list, not its caller, tell the user-supplied predicate what
stream to write to. This works only if the stream argument is just before
the di,uo pair of I/O state arguments, which differs from our usual practice
of passing the stream at or near the left edge of the argument list,
not near the right. The result of this complication is that two categories
of predicates that are and are not used to print items in a list differ
in where they put the stream in their argument lists. This makes it easy
to pass the stream in the wrong argument position if you call a predicate
without looking up its signature, and may require *changing* the argument
order when a predicate is used to print an item in a list for the first time.
A complete switch over to always passing the stream just before !IO
would fix this inconsistency, but is far to big a change to make all at once.

compiler/parse_tree_out_info.m:
    Make the changes described above.

    Add write_out_list, which is a variant of io.write_list specifically
    designed to address the "complication" described above. It also has
    the arguments in an order that is better suited for higher-order use.

    Make the same change to argument order in the class method add_list
    as well.

Almost all of the following changes consist of passing an extra stream
argument to output predicates. In some places, where I thought this would
aid readability, I replaced sequences of calls to output predicates
with a single io.format.

compiler/prog_out.m:
    This module had many predicates that wrote things to the current output
    stream. This diff adds versions of these predicates that take an
    explicit stream argument.

    If the originals are still needed after the changes to the other modules,
    keep them, but add "_to_cur_stream" to the end of their names.
    Otherwise, delete them. (Many of the changes below replace
    write_xyz(..., !IO) with io.write_string(Stream, xyz_to_string(...), !IO),
    especially when write_xyz did nothing except call xyz_to_string
    and wrote out the result.)

compiler/c_util.m:
    Add either an explicit stream argument to the argument list, or a
    "_current_stream" suffix to the name, of every predicate defined
    in this module that does output.

    Add a new predicate to print out the block comment containing
    input for mkinit. This factors out common code in the LLDS and MLDS
    backends.

compiler/name_mangle.m:
    Delete all predicates that used to write to the current output stream,
    after replacing them if necessary with functions that return a string,
    which the caller can print to wherever it wants. (The "if necessary"
    part is there because some of the "replacement" functions already
    existed.)

    When converting a proc_label to a string, *always* require the caller
    to say whether the label prefix should be added to the string,
    instead of silently assuming "yes, add it", as calls to one of the old,
    now deleted predicates had it.

compiler/file_util.m:
    Add output_to_file_stream, a version of output_to_file which
    simply passes the output file stream it opens to the predicate
    that is intended to define the contents of the newly created or
    updated file. The existing output_to_file, which instead sets
    and resets the current output stream around the equivalent
    predicate call, is still needed e.g. by the MLDS backend,
    but hopefully for not too long.

compiler/mercury_to_mercury.m:
compiler/parse_tree_out.m:
compiler/parse_tree_out_clause.m:
compiler/parse_tree_out_inst.m:
compiler/parse_tree_out_pragma.m:
compiler/parse_tree_out_pred_decl.m:
compiler/parse_tree_out_term.m:
compiler/parse_tree_out_type_repn.m:
    Change the code writing out parse trees to explicitly pass a stream
    to every predicate that does output.

    In some places, this allows us to avoid changing the identity
    of the current output stream.

compiler/hlds_out.m:
compiler/hlds_out_goal.m:
compiler/hlds_out_mode.m:
compiler/hlds_out_module.m:
compiler/hlds_out_pred.m:
compiler/hlds_out_util.m:
compiler/intermod.m:
    Change the code writing out HLDS code to explicitly pass a stream
    to every predicate that does output. (The changes to these modules
    belong in this diff because these modules call many of the output
    predicates in the parse tree package.)

    In hlds_out_util.m, delete some write_to_xyz(...) predicates that wrote
    the result of xyz_to_string(...) to the current output stream.
    Replace calls to the deleted predicates with calls to io.write_string
    with the string being written being computed by xyz_to_string.

    Add a predicate to hlds_out_util.m that outputs a comment containing
    the current context, if it is valid. This factors out code that used
    to be common to several of the other modules.

    In a few places in hlds_out_module.m, the new code generates a
    slighly different set of blank lines, but this should not be a problem.

compiler/layout_out.m:
compiler/llds_out_code_addr.m:
compiler/llds_out_data.m:
compiler/llds_out_file.m:
compiler/llds_out_global.m:
compiler/llds_out_instr.m:
compiler/llds_out_util.m:
compiler/opt_debug.m:
compiler/rtti_out.m:
    Change the code writing out the LLDS to explicitly pass a stream
    to every predicate that does output. (The changes to these modules
    belong in this diff because layout_out.m and rtti_out.m call
    many of the output predicates in the parse tree package,
    and through them, the rest of the LLDS backend is affected as well.)

compiler/make.module_dep_file.m:
compiler/mercury_compile_main.m:
compiler/mercury_compile_middle_passes.m:
    Replace code that sets and resets the current output stream
    with code that simply passes an explicit output stream to a
    predicate that now *takes* an explicit stream as an argument.

compiler/accumulator.m:
compiler/add_clause.m:
compiler/code_gen.m:
compiler/code_loc_dep.m:
compiler/cse_detection.m:
compiler/delay_partial_inst.m:
compiler/dep_par_conj.m:
compiler/det_analysis.m:
compiler/error_msg_inst.m:
compiler/export.m:
compiler/format_call.m:
compiler/goal_expr_to_goal.m:
compiler/ite_gen.m:
compiler/lco.m:
compiler/liveness.m:
compiler/lp_rational.m:
compiler/mercury_compile_front_end.m:
compiler/mercury_compile_llds_back_end.m:
compiler/mlds_to_c_file.m:
compiler/mlds_to_c_global.m:
compiler/mode_debug.m:
compiler/mode_errors.m:
compiler/modes.m:
compiler/optimize.m:
compiler/passes_aux.m:
compiler/pd_debug.m:
compiler/pragma_c_gen.m:
compiler/proc_gen.m:
compiler/prog_ctgc.m:
compiler/push_goals_together.m:
compiler/rat.m:
compiler/recompilation.m:
compiler/recompilation.usage.m:
compiler/recompilation.version.m:
compiler/rtti.m:
compiler/saved_vars.m:
compiler/simplify_goal_conj.m:
compiler/stack_opt.m:
compiler/structure_reuse.analysis.m:
compiler/structure_reuse.domain.m:
compiler/structure_reuse.indirect.m:
compiler/structure_sharing.analysis.m:
compiler/superhomogeneous.m:
compiler/term_constr_build.m:
compiler/term_constr_data.m:
compiler/term_constr_fixpoint.m:
compiler/term_constr_pass2.m:
compiler/term_constr_util.m:
compiler/tupling.m:
compiler/type_assign.m:
compiler/unneeded_code.m:
compiler/write_deps_file.m:
    Conform to the changes above, mostly by passing streams explicitly.

compiler/hlds_dependency_graph.m:
    Conform to the changes above, mostly by passing streams explicitly.
    Move a predicate's definition next it only use.

compiler/Mercury.options:
    Specify --warn-implicit-stream-calls for all the modules in which
    this diff has replaced all implicit streams with explicit streams.
    (Unfortunately, debugging this diff has shown that --warn-implicit-
    stream-calls detects only *some*, and not *all*, uses of implicit
    streams.)

library/term_io.m:
    Fix documentation.
2020-11-14 15:07:55 +11:00
Zoltan Somogyi
181ada0dbf Avoid -O<n> resetting previously set options.
This implements Mantis feature request #495.

NEWS:
    Announce the change.

compiler/optimization_options.m:
    A new module for managing optimization options.

    It defines a separate bespoke type for every boolean optimization option
    to make it harder to confuse them. It defines a tuple type (opt_tuple)
    for accessing optimization options quickly. It implements the turning on
    (but NOT turning off) of optimizations when a given optimization level
    is selected.

tools/make_optimization_options_middle:
tools/make_optimization_options_db:
    The script that generates the meat of optimization_options.m,
    and the database of option names, kinds and initial values
    that it uses as its input. The script also generates some code
    for the special_handler predicate in compiler/options.m.

tools/make_optimization_options_start:
tools/make_optimization_options_end:
    The handwritten initial and final parts of optimization_options.m.

tools/make_optimization_options:
    The script that pulls these parts together to form optimization_options.m.

compiler/options.m:
    Make every optimization option a special option, to be handled by
    the special_handler predicate. That handling consists of simply
    adding a representation of the option to the end of a cord of
    optimization options, to be processed later by optimization_options.m.
    That processing will record the values of these options in the opt_tuple,
    which is where every other part of the compiler should get them from.

    Change the interface of special_handler to make the above possible.

    Add an "optopt_" (optimization option) prefix to the name of
    every optimization option, to make them inaccessible to the rest
    of the compiler under their old name, and thus help enforce the switch
    to using the opt_tuple. Any access to these options to look up
    their values would fail anyway, since the option data would no longer be
    e.g. bool(yes), but bool_special, but the name change makes this failure
    happen at compile time, not runtime.

    Reclassify a few options to make the above make sense. Some options
    (unneeded_code_debug, unneeded_code_debug_pred_name, and
    common_struct_preds) were classified as oc_opt even though they
    control only the *debugging* of optimizations, while some options
    (c_optimize and inline_alloc) were not classified as oc_opt
    even though we do set them automatically at some optimization levels.

    Delete the opt_level_number option, since it was not used anywhere.

    Delete the code for handling -ON and --opt-space, since that is now
    done in optimization_options.m.

    Add some XXXs.

compiler/handle_options.m:
    Switch to using getopt_io.process_options_userdata_se, as required
    by the new interface of the special_handler in options.m.
    In the absence of errors, invoke optimization_options.m to initialize
    the opt_tuple. Then update the opt_tuple incrementally when processing
    option implications that affect optimization options.

compiler/globals.m:
    Put the opt_tuple into a new field of the globals structure.

compiler/accumulator.m:
compiler/add_pragma_type_spec.m:
compiler/add_trail_ops.m:
compiler/code_info.m:
compiler/code_loc_dep.m:
compiler/compile_target_code.m:
compiler/const_struct.m:
compiler/deforest.m:
compiler/dep_par_conj.m:
compiler/disj_gen.m:
compiler/erl_code_gen.m:
compiler/format_call.m:
compiler/global_data.m:
compiler/grab_modules.m:
compiler/higher_order.m:
compiler/hlds_pred.m:
compiler/inlining.m:
compiler/intermod.m:
compiler/ite_gen.m:
compiler/jumpopt.m:
compiler/libs.m:
compiler/llds_out_code_addr.m:
compiler/llds_out_data.m:
compiler/llds_out_file.m:
compiler/llds_out_instr.m:
compiler/llds_out_util.m:
compiler/matching.m:
compiler/mercury_compile_front_end.m:
compiler/mercury_compile_llds_back_end.m:
compiler/mercury_compile_main.m:
compiler/mercury_compile_middle_passes.m:
compiler/mercury_compile_mlds_back_end.m:
compiler/ml_disj_gen.m:
compiler/ml_gen_info.m:
compiler/ml_lookup_switch.m:
compiler/ml_optimize.m:
compiler/ml_proc_gen.m:
compiler/ml_simplify_switch.m:
compiler/ml_switch_gen.m:
compiler/ml_unify_gen_construct.m:
compiler/optimize.m:
compiler/pd_util.m:
compiler/peephole.m:
compiler/polymorphism.m:
compiler/proc_gen.m:
compiler/simplify_goal_call.m:
compiler/simplify_goal_scope.m:
compiler/simplify_info.m:
compiler/simplify_proc.m:
compiler/simplify_tasks.m:
compiler/stack_layout.m:
compiler/stack_opt.m:
compiler/switch_gen.m:
compiler/switch_util.m:
compiler/tag_switch.m:
compiler/tupling.m:
compiler/unify_gen_construct.m:
compiler/unneeded_code.m:
compiler/unused_args.m:
    Conform to the changes above, mostly by looking up optimization options
    in the opt_tuple. In some places, replace bools containing optimization
    options with the bespoke type of that specific optimization option.

library/getopt_template:
    Fix a bug that screwed up an error message.

    The bug happened when processing a --file option. If one of the
    options in the file was a special option whose special handler failed,
    the code handling that failing option returned both an error indication,
    and the rest of the argument list read in from the file. The code
    handling the --file option then *ignored* the error indication from
    the failed special option, and returned an error message of its own
    complaining about the unconsumed remaining arguments in the file,
    believing them to be non-option arguments, even though these arguments
    were never looked it to see if they were options.

    The fix is for the code handling --flag options to check whether
    the code processing the file contents found any errors, and if so,
    return that error *without* looking at the list of remaining arguments.

    In an unrelated change, factor out a duplicate call.
2020-09-28 18:16:13 +10:00
Zoltan Somogyi
6b06bc4e40 Use simplest_msg when possible. 2020-08-10 00:19:08 +10:00
Zoltan Somogyi
9789375cc5 Make pre-HLDS passes use file-kind-specific parse trees.
Replacing item blocks file-kind-specific kinds of section markers with
file-kind-specific parse trees has several benefits.

- It allows us to encode the structural invariants of each kind of file
  we read in within the type of its representation. This makes the detection
  of any accidental violations of those invariants trivial.

- Since each file-kind-specific parse tree has separate lists for separate
  kinds of items, code that wants to operate on one or a few kinds of items
  can just operate on those kinds of items, without having to traverse
  item blocks containing many other kinds of items as well. The most
  important consequence of this is not the improved efficiency, though
  that is nice, but the increased clarity of the code.

- The new design is much more flexible. For example, it should be possible
  to record that e.g. an interface file we read in as a indirect dependency
  (i.e. a file we read not because its module was imported by the module
  we are compiling, but because its module was imported by *another* imported
  module) should be used *only* for the purpose it was read in for. This should
  avoid situations where deleting an import of A from a module, because it
  is not needed anymore, leads the compiler to generate an error message
  about a missing import of module B. This can happen if (a) module B
  always *should* have been imported, since it is used, but (b) module A's
  import of module B lead to module B's interface being available *without*
  an import of B.

  Specifically, this flexibility should enable us to establish each module's
  .int file as the single source of truth about how values of each type
  defined in that module should be represented. When compiling each source
  file, this approach requires the compiler to read in that module's .int file
  but using only the type_repn items from that .int file, and nothing else.

- By recording a single parse tree for each file we have read, instead of
  a varying number of item blocks, it should be significantly easier to
  derive the contents of .d files directly from the records of those
  parse trees, *without* having to maintain a separate set of fields
  in the module_and_imports structure for that purpose. We could also
  trivially avoid any possibility of inconsistencies between these two
  different sources of truth. (We currently fill in the fields used to
  drive the generation of .d files using two different pieces of code,
  one used for --generate-dependencies and one used for all other invocations,
  and these two *definitely* generate inconsistent results, as the significant
  differences in .d files between (a) just after an invocation of
  --generate-dependencies and (b) just after any other compiler invocation
  can witness.)

This change is big and therefore hard to review. Therefore in many files,
this change adds "XXX CLEANUP" comments to draw attention to places that
have issues that should be fixed, but whose fixes should come later, in
separate diffs.

compiler/module_imports.m:
    The compiler uses the module_and_imports structure defined here
    to go from a raw compilation unit (essentially a module to be compiled)
    to an augmented compilation unit (a raw compilation unit together
    with all the interface and optimization files its compilation needs).
    We used to store the contents of both the source file and of
    the interface and optimization files in the module_and_imports structure
    as item blocks. This diff replaces all those item blocks with
    file-kind-specific parse trees, for the reasons mentioned above.

    Separate out the .int0 files of ancestors modules from the .intN
    files for N>0 of directly imported modules. (Their item blocks
    used to be stored in the same list.)

    Maintain a database of the source, interface and optimization files
    we have read in so far. We use it to avoid reading in interface files
    if we have already read in a file for the same module that contains
    strictly more information (either an interface file with a smaller
    number as a suffix, or the source file itself).

    Shorten some field names.

compiler/prog_item.m:
    Define data structures for storing information about include_module,
    import_module and use_module declarations, both in a form that allows
    the representation of possibly erroneous code in actual source files,
    and in checked-and-cleaned-up form which is guaranteed to be free
    of the relevant kinds of errors. Add a block comment at the start
    of the module about the need for this distinction.

    Define parse_tree_module_src, a data structure for representing
    the source code of a single module. This is different from the existing
    parse_tree_src type, which represents the contents of a single source file
    but which may contain *more* than one module, and also different from
    a raw_compilation_unit, which is based on item blocks and is thus
    unable to express to invariants such as "no clauses in the interface".

    Modify the existing parse_tree_intN types to express the distinction
    mentioned just above, and to unify them "culturally", i.e. if they
    store the same information, make them store it using the same types.

    Fix a mistake by allowing promises to appear in .opt files.
    I originally ruled them out because the code that generates .opt files
    does not have any code to write out promises, but some of the predicates
    whose clauses it writes out have goal_type_promise, which means that
    they originated as promises, and get written out as promises.

    Split the existing pragma item kind into three item kinds, which have
    different invariants applying to them.

    - The decl (short for declarative) pragmas give the compiler some
      information, such as that a predicate is obsolete or that we
      want to type specialize some predicate or function, that is in effect
      part of the module's interface. Decl pragmas may appear in module
      interfaces, and the compiler may put them into interface files;
      neither statement is true of the other two kinds of pragmas.

    - The impl (short for implementation) pragmas are named so
      precisely because they may appear only in implementation sections.
      They give the compiler information that is private to that module.
      Examples include foreign_decls, foreign_codes, foreign_procs,
      and promises of clause equivalence, and requests for inlining,
      tabling etc. These will never be put into interface files,
      though some of them can affect the compilation of other modules
      by being included in .opt files.

    - The gen (short for generated) pragmas can never (legally) appear
      in source files at all. They record the results of compiler
      analyses e.g. about which arguments of a predicate are unused,
      or what exceptions a function can throw, and accordingly they
      should only ever occur in compiler-generated interface files.

    Use the new type differences between the three kinds of pragmas
    to encode the above invariants about which kinds of pragmas can appear
    where into the various kinds of parse trees.

    Make the augmented compilation unit, which is computed from
    the final module_and_imports structure, likewise switch from
    storing item blocks to storing the whole parse trees of the
    files that went into its construction. With each such parse tree,
    record *why* we read it, since this controls what permissions
    the source module being compiled has for access to the entities
    in the parse tree.

    Simplify the contains_foreign_code type, since one of three
    function symbols was equivalent to one possible use of another
    function symbol.

    Provide a way to record which method of which class a compiler-generated
    predicate is for. (See hlds_pred.m below.)

    Move the code of almost all utility operations to item_util.m
    (which is imported by many fewer modules than prog_item.m),
    keeping just the most "popular" ones.

compiler/item_util.m:
    Move most of the previously-existing utility operations here from
    prog_item.m, most in a pretty heavily modified form.

    Add a whole bunch of other utility operations that are needed
    in more than one other module.

compiler/convert_parse_tree.m:
    Provide predicates to convert from raw compilation units to
    parse_tree_module_srcs, and vice versa (though the reverse
    shouldn't be needed much longer).

    Update the conversion operations between the general parse_tree_int
    and the specific parse_tree_intN forms for the changes in prog_item.m
    mentioned above. In doing so, use a consistent approach, based on
    new operations in item_util.m, to detect errors such as duplicate
    include_module and import/use_module declarations in all kinds
    of parse trees.

    Enforce the invariants that the types of parse trees of various kinds
    can now express in types, generating error messages for their violations.

    Delete some utility operations that have been moved to item_util.m
    because now they are also needed by other modules.

compiler/grab_modules.m:
    Delete code that did tests on raw compilation units that are now done
    when that raw compilation unit is converted to a parse_tree_module_src.
    Use the results of the checks done during that conversion to decide
    which modules are imported/used and in which module section.

    Record a single reason for why we reading in each interface and
    optimization file. The code of make_hlds_separate_items.m will use
    this reason to set up the appropriate permissions for each item
    in those files.

    Use separate code for handling different kinds of interface and
    optimization files. Using generic traversal code was acceptable economy
    when we used the same data structure for every kind of interface file,
    but now that we *can* express different invariants for different kinds
    of interface and optimization file, we want to execute not just different
    code for each kind of file, but the data structures we want to work on
    are also of different types. Using file-kind-specific code is a bit
    longer, but it is significantly simpler and more robust, and it is
    *much* easier to read and understand.

    Delete the code that separates the parts of the implementation section
    that are exported to submodules, and the part that isn't, since that task
    is now done in make_hlds_separate_items.m.

    Pass a database of the files we have read through the relevant predicates.

    Give some predicates more meaningful names.

compiler/notes/interface_files.html:
    Note a problem with the current operation of grab_modules.

compiler/get_dependencies.m:
    Add operations to gather implicit references to builtin modules
    (which have to be made available even without an explicit import_module
    or use_module declaration) in all kinds of parse trees. These have
    more code overall, but will be at runtime, since we need only look at
    the item kinds that may *have* such implicit references.

    Add a mechanism to record the result of these gathering operations
    in import_and_or_use_maps.

    Give some types, function symbols, predicates and variables
    more meaningful names.

compiler/make_hlds_separate_items.m:
    When we stored the contents of the source module and the
    interface and optimization files we read in to augment it
    in the module_and_imports structure as a bunch of item blocks,
    the job of this module was to separate out the different kinds of items
    in the item blocks, returning a single list of each kind of item,
    with each such item being packaged up with its status (which encodes
    a set of permissions saying what the source module is allowed
    to do with it).

    Now that the module_and_imports structure stores this info in
    file-kind-specific parse trees, all of which have separate lists
    for each kind of item and none of which contain item blocks,
    the job of this module has changed. Now its job is to convert
    the reason why each file was read in into the (one or more) statuses
    that apply to the different kinds of items stored in it, wrap up
    each item with its status, and return the resulting overall list
    of status/item pairs for each kind of item.

compiler/read_modules.m:
    Add predicates that, when reading an interface file, return its contents
    in the tightest possible file-kind-specific parse tree.

    Refine the database of files we have read to allow us to store
    more file-kind-specific parse trees.

    Don't require that files in the database have associated timestamps,
    since in some cases, we read files we can put into the database
    *without* getting their timestamps.

    Allow the database to record that an attempt to read a file failed.

compiler/split_parse_tree_src.m:
    Rearchitect how this module separates out nested submodules from within
    the main module in a file.

    Another of the jobs of this module is to generate error messages for
    when module A includes module B twice, whether via nesting or via
    include_module declarations, with one special exception for the case
    where A's interface contains nested submodule A.B's interface,
    and A's implementation contains nested submodule A.B's implementation.
    The problem ironically was that while it reported duplicate include_module
    declarations as errors, split_parse_tree_src.m also *generated*
    duplicate include_module declarations. Since it replaced each nested
    submodule occurrence with an include_module declaration, in the scenario
    above, it generated two include_module declarations for A.B. Even worse,
    the interface incarnation of submodule A.B could contain
    (the interface of) its own nested submodule A.B.C, while its
    implementation incarnation could contain (the implementation section of)
    A.B.C. Each occurrence of A.B.C would be its only occurrence in the
    including part of its parent A.B, which means local tests for duplicates
    do not work. (I found this out the hard way.)

    The solution we now adopt adds include_module declarations to the
    parents of any submodule only once the parse tree of the entire
    file has been processed, since only then do we know all the
    includer/included relationships among nested modules. Until then,
    we just record such relationships in a database as we discover them,
    reporting duplicates when needed (e.g. when A includes B twice
    *in the same section*), but not reporting duplicates when not needed
    (e.g. when A.B includes A.B.C in *different* sections).

compiler/prog_data.m:
    Add a new type, pf_sym_name_and_arity, that exactly specifies
    a predicate or function. It is a clone of the existing simple_call_id
    type, but its name does NOT imply that the predicate or function
    is being called.

    Add XXXs that call for some other improvements in type names.

compiler/prog_data_foreign.m:
    Give a type, and the operations on that type, a more specific name.

compiler/error_util.m:
    Add an id field to all error_specs, which by convention should be
    filled in with $pred. Print out the value in this field if the compiler
    is invoked with the developer-only option --print-error-spec-id.
    This allows a person debugging the compiler find out where in the code
    an undesired error message is coming from significantly easier
    than was previously possible.

    Most of the modules that have changes only "to conform to the changes
    above" will be for this change. In many cases, the updated code
    will also simplify the creation of the affected error_specs.

    Fix a bug that looked for a phase in only one kind of error_spec.

    Add some utility operations needed by other parts of this change.

    Delete a previously internal function that has been moved to
    mdbcomp/prim_data.m to make it accessible in other modules as well.

compiler/Mercury.options:
    Ask the compiler to warn about dead predicates in every module
    touched by this change (at least in one its earlier versions).

compiler/add_foreign_enum.m:
    Replace a check for an inappropriately placed foreign_enum declaration
    with a sanity check, since with this diff, the error should be caught
    earlier.

compiler/add_mutable_aux_preds.m:
    Delete a check for an inappropriately placed mutable declaration,
    since with this diff, the error should be caught earlier.

compiler/add_pragma.m:
    Instead of adding pass2 and pass3 pragmas, add decl and impl and
    generated pragmas.

    Delete the tests for generated pragma occurring anywhere except
    .opt files, since those tests are now done earlier.

    Shorten some too-long predicate names.

compiler/comp_unit_interface.m:
    Operate on as specific kinds of parse trees as the interface of this
    module will allow. (We could operate on more specific parse trees
    if we changed the interface, but that is future work).

    Use the same predicates for handling duplicate include_module,
    import_module and use_module declarations as everywhere else.

    Delete the code of an experiment that shouldn't be needed anymore.

compiler/equiv_type.m:
    Replace code that operated on item blocks with code that operates
    on various kinds of parse trees.

    Move a giant block of comments to the front, where it belongs.

compiler/hlds_module.m:
    Add a field to the module_info that lets us avoid generating
    misleading error messages above missing definitions of predicates
    or functions when those definitions were present but were not
    added to the HLDS because they had errors.

    Give a field and its access predicates a more specific name.

    Mark a spot where an existing type cannot express everything
    it is supposed to.

compiler/hlds_pred.m:
    For predicates which the compiler creates to represent a class method
    (the virtual function, in OOP terms), record not just this fact,
    but the id of the class and of the method. Using this extra info
    in progress messages (with mmc -V) prevents the compiler from printing e.g.

        % Checking typeclass constraints on class method
        % Checking typeclass constraints on class method
        % Checking typeclass constraints on class method

    when checking three such predicates.

compiler/make.m:
    Provide a slot in the make_info structure to allow the database
    of the files we have read in to be passed around.

compiler/make_hlds_error.m:
    Delete predicates that are needed in just one other module,
    and have therefore been moved there.

compiler/make_hlds_passes.m:
    Add decl, impl and generated pragma separately, instead of adding
    pass2 and pass3 pragmas separately.

    Do not generate error messages for clauses, initialises or finalises
    in module interfaces, since with this diff, such errors should be
    caught earlier.

compiler/mercury_compile_main.m:
compiler/recompilation.check.m:
    Explicitly pass around the expanded database of parse trees
    of files that have been read in.

compiler/module_qual.collect_mq_info.m:
compiler/module_qual.m:
compiler/module_qual.qualify_items.m:
    Collect module qualification information, and do module qualification
    respectively on parse trees of various kinds, not item blocks.
    Take information about what the module may do with the contents
    of each interface or optimization file from the record of why
    we read that file, not from the section markers in item blocks.

    Break up some too-large predicates by carving smaller ones out of them.

compiler/options.m:
    Add an option to control whether errors and/or warnings detecting
    when deciding what should go into a .intN file be printed,
    thus (potentially) preventing the creation of that file.

    Add commented-out documentation for a previously totally undocumented
    option.

doc/user_guide.texi:
    Document the new option.

NEWS:
    Announce the new option.

    Mention that we now generate warnings for unused import_module and
    use_module declarations in the interface even if the module has
    submodules.

compiler/write_module_interface_files.m:
    Let the new option control whether we filter out any messages generated
    when deciding what should go into a .intN file.

compiler/parse_item.m:
    Delete actually_read_module_opt, since it is no longer needed;
    its callers now call actually_read_module_{plain,trans}_opt instead.

    Delete unneeded arguments from some predicates.

compiler/parse_module.m:
    Delete some long unused predicates.

compiler/parse_pragma.m:
    When parsing pragmas, wrap them up in the new decl, impl or generated
    pragma kinds.

compiler/parse_tree_out.m:
    Add predicates to write out each of the file-kind-specific parse trees.

compiler/parse_tree_out_pragma.m:
    Add predicates to write out decl, impl and generated pragmas.

compiler/polymorphism.m:
    Add a conditionally-enabled progress message, which can be useful
    in tracking down problems.

compiler/prog_item_stats.m:
    Conform NOT to the changes above beyond what is needed to let this module
    compile. Let that work be done the next time the functionality of
    this module is needed, by which time the affected data structures
    maybe have changed further.

compiler/typecheck.m:
    Fix a performance problem. With intermodule optimization, we read in
    .opt files, some of which (e.g. list.opt and int.opt) contain promises.
    These promises are read in as predicates with goal_type_promise,
    but they do not have declarations of the types of their arguments
    (since promises do not have declarations as such). Those argument types
    therefore have to be inferred. That inference replaces the original
    "I don't know" argument types with their actual types.

    The performance problem is that when we change the recorded argument types
    of a predicate, we require another loop over all the predicates in the
    module, so that any calls to this predicate can be checked against
    the updated types. This is as it should be for callable predicates,
    but promises are not callable. So if all the *only* predicates whose
    recorded argument types change during the first iteration to fixpoint
    are promises, then a second iteration is not needed, yet we used to do it.

    The fix is to replace the "Have the recorded types of this predicate
    changed?" boolean flag with a bespoke enum that says "Did the checking
    of this predicate discover a need for another iteration", and not
    setting it when processing predicates whose type is goal_type_promise.

compiler/typecheck_errors.m:
    Do not generate an error message for a predicate missing its clauses
    is the clauses existed but were not added to the HLDS because they were
    in the interface section.

    When reporting on ambiguities (when a call can match more than one
    predicate or function), sort the possible matches before reporting
    them.

compiler/accumulator.m:
compiler/add_class.m:
compiler/add_clause.m:
compiler/add_foreign_proc.m:
compiler/add_mode.m:
compiler/add_pragma_tabling.m:
compiler/add_pragma_type_spec.m:
compiler/add_pred.m:
compiler/add_type.m:
compiler/canonicalize_interface.m:
compiler/check_for_missing_type_defns.m:
compiler/check_parse_tree_type_defns.m:
compiler/check_promise.m:
compiler/check_raw_comp_unit.m:
compiler/check_typeclass.m:
compiler/common.m:
compiler/compile_target_code.m:
compiler/compiler_util.m:
compiler/dead_proc_elim.m:
compiler/deps_map.m:
compiler/det_analysis.m:
compiler/det_report.m:
compiler/du_type_layout.m:
compiler/field_access.m:
compiler/find_module.m:
compiler/float_regs.m:
compiler/format_call.m:
compiler/goal_expr_to_goal.m:
compiler/handle_options.m:
compiler/hlds_out_module.m:
compiler/hlds_out_pred.m:
compiler/hlds_out_util.m:
compiler/inst_check.m:
compiler/intermod.m:
compiler/introduce_parallelism.m:
compiler/layout_out.m:
compiler/make.dependencies.m:
compiler/make.module_dep_file.m:
compiler/make_hlds_warn.m:
compiler/mark_tail_calls.m:
compiler/mercury_compile_llds_back_end.m:
compiler/ml_top_gen.m:
compiler/mmakefiles.m:
compiler/mode_errors.m:
compiler/mode_robdd.equiv_vars.m:
compiler/modes.m:
compiler/module_qual.qual_errors.m:
compiler/oisu_check.m:
compiler/old_type_constraints.m:
compiler/options_file.m:
compiler/parse_class.m:
compiler/parse_dcg_goal.m:
compiler/parse_goal.m:
compiler/parse_inst_mode_defn.m:
compiler/parse_inst_mode_name.m:
compiler/parse_mutable.m:
compiler/parse_sym_name.m:
compiler/parse_type_defn.m:
compiler/parse_type_name.m:
compiler/parse_type_repn.m:
compiler/parse_types.m:
compiler/parse_util.m:
compiler/parse_vars.m:
compiler/post_term_analysis.m:
compiler/post_typecheck.m:
compiler/prog_event.m:
compiler/prog_mode.m:
compiler/purity.m:
compiler/qual_info.m:
compiler/recompilation.version.m:
compiler/resolve_unify_functor.m:
compiler/simplify_goal.m:
compiler/simplify_goal_call.m:
compiler/simplify_goal_disj.m:
compiler/simplify_goal_ite.m:
compiler/simplify_proc.m:
compiler/state_var.m:
compiler/stratify.m:
compiler/style_checks.m:
compiler/superhomogeneous.m:
compiler/table_gen.m:
compiler/term_constr_errors.m:
compiler/term_errors.m:
compiler/termination.m:
compiler/trace_params.m:
compiler/unused_args.m:
compiler/unused_imports.m:
compiler/write_deps_file.m:
compiler/xml_documentation.m:
    Conform to the changes above.

mdbcomp/prim_data.m:
    Move a utility function on pred_or_funcs here from a compiler module,
    to make it available to other compiler modules as well.

scripts/compare_s1s2_lib:
    A new script that helped debug this diff, and may help debug
    similar diffs the future. It can compare (a) .int* files, (b) .*opt
    files, (c) .mh/.mih files or (d) .c files between the stage 1 and
    stage 2 library directories. The reason for the restriction
    to the library directory is that any problems affecting the
    generation of any of these kinds of files are likely to manifest
    themselves in the library directory, and if they do, the bootcheck
    won't go on to compile any of the other stage 2 directories.

tests/debugger/breakpoints.a.m:
tests/debugger/breakpoints.b.m:
    Move import_module declarations to the implementation section
    when they are not used in the interface. Until now, the compiler
    has ignored this, but this diff causes the compiler to generate
    a warning for such misplaced import_module declarations even modules
    that have submodules. The testing of such warnings is not the point
    of the breakpoints test.

tests/invalid/Mercury.options:
    Since the missing_interface_import test case tests error messages
    generated during an invocation of mmc --make-interface, add the
    new option that *allows* that invocation to generate error messages.

tests/invalid/ambiguous_overloading_error.err_exp:
tests/invalid/max_error_line_width.err_exp:
tests/warnings/ambiguous_overloading.exp:
    Expect the updated error messages for ambiguity, in which
    the possible matches are sorted.

tests/invalid/bad_finalise_decl.m:
tests/invalid/bad_initialise_decl.m:
    Fix programming style.

tests/invalid/bad_item_in_interface.err_exp:
    Expect an error message for a foreign_export_enum item in the interface,
    where it should not be.

tests/invalid/errors.err_exp:
    Expect the expanded wording of a warning message.

tests/invalid/foreign_enum_invalid.err_exp:
    Expect a different wording for an error message. It is more "standard"
    but slightly less informative.

tests/invalid_submodules/children2.m:
    Move a badly placed import_module declaration, to avoid having
    the message the compiler now generates for it from affecting the test.

tests/submodules/parent2.m:
    Move a badly placed import_module declaration, to avoid having
    the message the compiler now generates for it from affecting the test.

    Update programming style.
2020-03-13 12:58:33 +11:00
Zoltan Somogyi
df9420c3e6 Flatten the unify_mode structure.
compiler/hlds_goal.m:
    Change the unify_mode structure from

        unify_modes_lhs_rhs(from_to_insts(LI, LF), from_to_insts(RI, RF))

    to

        unify_modes_li_lf_ri_rf(LI, LF, RI, RF)

    This requires fewer memory allocations (1 vs 3) and less memory
    (4 words vs 6), though the performance improvement is too small
    to measure.

    It should also require writing fewer function symbols in code.

compiler/instmap.m:
compiler/mode_util.m:
    For each utility predicate that works with from_to_insts, provide
    a version that works with the separate insts contained in it.
    Delete the from_to_insts version if no longer needed.

compiler/prog_mode.m:
    Delete utility predicates on from_to_insts that are not needed anymore.

compiler/accumulator.m:
compiler/add_pred.m:
compiler/bytecode_gen.m:
compiler/common.m:
compiler/const_prop.m:
compiler/deep_profiling.m:
compiler/delay_partial_inst.m:
compiler/dep_par_conj.m:
compiler/equiv_type_hlds.m:
compiler/erl_unify_gen.m:
compiler/float_regs.m:
compiler/format_call.m:
compiler/goal_util.m:
compiler/higher_order.m:
compiler/hlds_out_goal.m:
compiler/hlds_out_mode.m:
compiler/interval.m:
compiler/lambda.m:
compiler/lco.m:
compiler/make_goal.m:
compiler/ml_unify_gen_construct.m:
compiler/ml_unify_gen_util.m:
compiler/modecheck_goal.m:
compiler/modecheck_unify.m:
compiler/polymorphism.m:
compiler/proc_requests.m:
compiler/prog_rep.m:
compiler/rbmm.region_transformation.m:
compiler/simplify_goal_call.m:
compiler/simplify_goal_scope.m:
compiler/simplify_goal_switch.m:
compiler/size_prof.m:
compiler/stm_expand.m:
compiler/term_util.m:
compiler/unify_gen_construct.m:
compiler/unify_gen_util.m:
compiler/unused_args.m:
    Conform to the changes above.
2019-10-27 02:53:46 +11:00
Zoltan Somogyi
17d684a11e Better arg orders in instmap.m.
compiler/instmap.m:
    Replace a non-state-var-friendly and a state-var-friendly pair
    of predicates with just one state-var-friendly predicate.

    Improve the arg order of another predicate as well.

    Improve documentation.

compiler/accumulator.m:
compiler/call_gen.m:
compiler/code_loc_dep.m:
compiler/constraint.m:
compiler/cse_detection.m:
compiler/delay_construct.m:
compiler/dep_par_conj.m:
compiler/erl_code_gen.m:
compiler/erl_code_util.m:
compiler/float_regs.m:
compiler/goal_mode.m:
compiler/goal_util.m:
compiler/hlds_pred.m:
compiler/introduce_parallelism.m:
compiler/lookup_util.m:
compiler/loop_inv.m:
compiler/mode_util.m:
compiler/modecheck_unify.m:
compiler/par_conj_gen.m:
compiler/pd_info.m:
compiler/pd_util.m:
compiler/prog_rep.m:
compiler/stm_expand.m:
compiler/transform.m:
compiler/try_expand.m:
compiler/unneeded_code.m:
    Conform to the change above. Delete unneeded module qualifications.
2019-08-24 17:18:14 +10:00
Zoltan Somogyi
c1bdd2100b Delete unneeded $module args from aborts. 2019-04-16 04:13:35 +10:00
Zoltan Somogyi
f0db887cd3 Move promises from hlds_data.m to the new hlds_promise.m.
compiler/hlds_promise.m:
    New module carved out of hlds_data.m.

compiler/hlds_data.m:
    Delete the moved code.

compiler/hlds.m:
compiler/notes/compiler_design.html:
    Include the new module.

compiler/accumulator.m:
compiler/assertion.m:
compiler/check_promise.m:
compiler/hlds_module.m:
compiler/hlds_pred.m:
compiler/intermod.m:
    Conform to the change above.
2018-02-05 23:39:52 +11:00
Zoltan Somogyi
d9e576a2b2 Specify the type for inst definitions.
browser/*.m:
compiler/*.m:
deep_profiler/*.m:
library/*.m:
mdbcomp/*.m:
ssdb/*.m:
    Specify the type constructor for every inst definition that lists
    the functors that values of that type may be bound to.

    In library/maybe.m, delete the inst maybe_errors/1, because
    (a) its name is misleading, since it is for the maybe_error/1 type (no s),
    and (b) there is already an inst with the non-misleading name maybe_error
    which had an identical definition.

    In compiler/dep_par_conj.m, delete two insts that were duplicates
    of insts defined in hlds_goal.m, and replace references to them
    accordingly.
2017-11-08 16:54:18 +11:00
Zoltan Somogyi
dfd67afbd7 Rename a warning option to make it fit in with others.
compiler/options.m:
    Rename --inhibit-accumulator-warnings as --no-warn-accumulator-swaps.
    This is better for two reasons: it says explicitly what kinds of warnings
    it talks about (swaps of accumulator arguments may lead to slowdowns),
    and it allows us to treat the option the same as all the other options
    that enable warnings.

    Separate out the lists of warning options into two lists: the style
    and the non-style warnings, now that all these options are positive
    (i.e. they enable options when set).

NEWS:
    Mention the rename.

compiler/accumulator.m:
doc/user_guide.texi:
tests/warnings/arg_order_rearrangment.exp:
    Conform to the rename.
2017-04-24 22:24:33 +10:00
Zoltan Somogyi
3597d43db4 Replace pairs with bespoke types in assertions.
compiler/assertion.m:
    Return information about each kind assertion in a bespoke type.

compiler/accumulator.m:
    Conform to the change above.
2017-04-04 14:44:39 +10:00
Zoltan Somogyi
e203521c5b Fix programming style. 2017-04-04 05:13:30 +10:00
Zoltan Somogyi
95ff02b1bf Add options to check the ordering of module contents.
One option, --warn-non-contiguous-decls, generates warnings if the
mode declarations of a predicate or function aren't in a contiguous block
immediately following the pred or func declaration. Since this is a rare
kind of "style error", this option is enabled by default.

Two options, --warn-inconsistent-pred-order-clauses and
--warn-inconsistent-pred-order-foreign-procs, warn about inconsistencies
between (a) the order in which predicates (and functions) are declared,
and (b) the order in which they are defined. The two options differ in
their scope. The latter applies to all predicates and functions defined
in the module, while the former applies only to those whose definitions
include Mercury clauses.

Since an exported predicate or function may need nonexported auxiliary
predicates and/or functions, imposing a single order the declarations and
definitions of *all* the predicates and functions in a module is not a good
idea. Instead, both options divide the predicates and functions defined
in a module two groups, the exported and the nonexported, and expect
a consistent order only within each group.

The result is output that looks like this:

    time.m:021: Warning: the order of the declarations and definitions of the
    time.m:021:   exported predicates is inconsistent, as shown by this diff:
    time.m:021:
    time.m:021:   --- declaration order
    time.m:021:   +++ definition order
    time.m:021:   @@ -1,7 +1,7 @@
    time.m:021:    predicate `clock'/3
    time.m:021:   -predicate `time'/3
    time.m:021:    predicate `times'/4
    time.m:021:    function `clk_tck'/0
    time.m:021:   +predicate `time'/3
    time.m:021:    function `difftime'/2
    time.m:021:    predicate `localtime'/4
    time.m:021:    function `localtime'/1

compiler/options.m:
doc/user_guide.texi:
    Add the new options.

compiler/style_checks.m:
    A new module that generates the new warnings if warranted.

compiler/check_hlds.m:
compiler/notes/compiler_design.html:
    Include and document the new module.

compiler/mercury_compile_front_end.m:
    Invoke the new module if any of the three new options is set.

compiler/hlds_pred.m:
    Record the item number of every predicate, function, and mode declaration
    in the module being compiled. We need this for information for the
    new warnings.

compiler/hlds_module.m:
    Record the context of the module declaration. We use this context
    for warnings about inconsistent order, since there isn't a better one.

compiler/hlds_clauses.m:
    Add a mechanism to retrieve the item numbers of a set of clauses
    even if they are contiguous.

    Document some old data types.

compiler/error_util.m:
    Add a new phase for style checks.

compiler/accumulator.m:
compiler/add_class.m:
compiler/add_mutable_aux_preds.m:
compiler/add_pragma_tabling.m:
compiler/add_pred.m:
compiler/add_solver.m:
compiler/add_special_pred.m:
compiler/check_typeclass.m:
compiler/clause_to_proc.m:
compiler/from_ground_term_util.m:
compiler/lambda.m:
compiler/make_hlds.m:
compiler/make_hlds_passes.m:
compiler/mercury_compile.m:
compiler/par_loop_control.m:
compiler/polymorphism.m:
compiler/stm_expand.m:
compiler/table_gen.m:
compiler/unify_proc.m:
    Conform the changes to the HLDS above.

compiler/typecheck_errors.m:
    Fix style of error messages.

library/array2d.m:
library/assoc_list.m:
library/benchmarking.m:
library/bit_buffer.write.m:
library/bool.m:
library/builtin.m:
library/construct.m:
library/cord.m:
library/counter.m:
library/float.m:
library/injection.m:
library/lazy.m:
library/lexer.m:
library/ops.m:
library/private_builtin.m:
library/profiling_builtin.m:
library/prolog.m:
library/queue.m:
library/rational.m:
library/require.m:
library/stack.m:
library/std_util.m:
library/store.m:
library/thread.semaphore.m:
library/tree234.m:
library/univ.m:
library/version_store.m:
    Move declarations or definitions around to avoid some of the warnings
    that we can now generate. (There are many more left.)

    Make some minor style improvements in the process.

tests/warnings/inconsistent_pred_order.{m,exp}:
tests/warnings/non_contiguous_decls.{m,exp}:
    New test cases to test the new options. They are both copies of
    tests/benchmarks/queens.m, with intentionally-screwed-up style.

tests/warnings/Mmakefile:
    Enable the new test cases.

tests/warnings/Mercury.options:
    Specify the options being tested for the new test cases.

tests/benchmarks/queens.m:
    Bring the style of this module up to date (before copying it).

tests/invalid/mode_decl_in_wrong_section.err_exp:
    Expect the warnings we now generate.
2016-10-15 17:26:32 +11:00
Zoltan Somogyi
cfcfde1db7 Simplify the representation of modes of unifications.
Unifications (x = y) have long had two descriptions of their modes.
One is the unify_mode, which used to look like this:
    (initx -> finalx) - (inity -> finaly)
and other is the uni_mode, which used to look like this:
    (initx - inity) -> (finalx - finaly)
Each unification had one unify_mode, and each unification that includes
a function symbol had one uni_mode per argument of that function symbol.

The two forms of mode information looked similar enough to be easily
confusable, but were subtly different. As it turns out, there was no
particular reason for the difference, so this diff eliminates the
uni_mode type, and the difference along with it.

What rationale there was for the uni_mode type was that the two modes
it represented (one for each side of the unification) both had their
initial and final insts directly available. This is not true for modes
in general: a value of the mer_mode type could have the form
"InitInst -> FinalInst" (which this diff renames "from_to_mode(InitInst,
FinalInst)", but could also be a "user_defined_inst(...)", which required
a table lookup to turn it into an initial/final pair of insts. This matters,
because almost all code that processes the modes of unifications
works with the initial and final insts.

This diff therefore creates a new type, from_to_insts, which represents
mode information only in the form of terms such as "from_to_insts(InitInst,
FinalInst)", and makes a unify_mode take two values of this type, not mer_mode,
as arguments.

As discussed on m-rev, this diff also renames the old, deceptively named
"arg_mode" type: its new name is "top_functor_mode".

compiler/prog_data.m:
compiler/hlds_goal.m:
    As mentioned above, avoid using "->" as a function symbol, and replace
    both -> and - with bespoke function symbols.

compiler/mode_util.m:
    Add some utility predicates and functions on the new types, and
    delete the old utility routines that operated on uni_modes.

    Code that uses the new functions and predicates should have a higher level
    of abstraction than the code that used to do the same job "manually".

compiler/*.m:
    Conform to the changes above, using the new utility predicates and
    functions where relevant. In several cases, this required fixing
    confusion of the kind described at the top. In all but one case,
    the confusion affected only variable names, but in one case,
    deconstruct_functor in make_goal.m, it caused a bug. The bug has
    had no effect up till now because deconstruct_functor is called
    only from three places: try_expand.m, stm_expand.m, and untupling.m.
    The incorrect mode (which was the nonsensical ground -> free)
    generated by the code of try_expand.m itself was discarded and
    overwritten when try_expand.m invoked the modechecker. (I don't
    know whether this bugfix makes that invocation redundant or not.)
    The other two modules, stm_expand.m and untupling.m, may do something
    similar, but in any case, they don't yet work for other reasons.
    (A bootcheck with --untupling causes a compiler abort when compiling
    deep_profiler/query.m in stage 2 both without and with this fix.)

    Delete no-longer-needed imports of the pair module (and of some other
    modules).

    Put the arguments of some predicates into a more logical order.

    In bytecode_gen.m, replace clauses with disjunctions, and delete the
    arguments that this step has revealed to be unused.
2016-05-19 10:43:24 +10:00
Zoltan Somogyi
02466fbf52 Delete some unused predicates; add consider_used pragmas for some others. 2015-12-29 20:38:01 +11:00
Mark Brown
b2ae55c29c Change 'none' to 'none_or_default_func' in ho_inst_info.
This value of ho_inst_info is used for first-order values as well as
for functions that have the default inst, and the new name better
reflects that.

Places using this value have been checked for correctness. Issues that
need to be looked at have been marked with XXX, although have not been
addressed in this change.

compiler/prog_data.m:
	Update the type.

compiler/inst_match.m:
	Add XXX comments. This module needs to check for non-default
	function insts in a bunch of places.

compiler/inst_util.m:
	Add XXX comments. We lose information about non-default function
	insts when merging bound and any. The information needs to be
	either preserved or disallowed entirely.

compiler/float_regs.m:
	Add XXX comments. This module may miss cases involving default
	function insts.

compiler/modecheck_unify.m:
	Add XXX comment. We should exclude pred and non-default func
	lambda non-locals from becoming locked, an addition to default
	functions.

compiler/*.m:
	No special handling is required for other modules.
2015-11-16 21:13:04 +11:00
Zoltan Somogyi
cc9912faa8 Don't import anything in packages.
Packages are modules whose only job is to serve as a container for submodules.
Modules like top_level.m, hlds.m, parse_tree.m and ll_backend.m are packages
in this (informal) sense.

Besides the include_module declarations for their submodules, most of the
packages in the compiler used to import some modules, mostly other packages
whose component modules their submodules may need. For example, ll_backend.m
used to import parse_tree.m. This meant that modules in the ll_backend package
did not have to import parse_tree.m before importing modules in the parse_tree
package.

However, this had a price. When we add a new module to the parse_tree package,
parse_tree.int would change, and this would require the recompilation of ALL
the modules in the ll_backend package, even the ones that did NOT import ANY
of the modules in the parse_tree package.

This happened even at one remove. Pretty much all modules in every one
of the backend have to import one or more modules in the hlds package,
and they therefore have import hlds.m. Since hlds.m imported transform_hlds.m,
any addition of a new middle pass to the transform_hlds package required
the recompilation of all backend modules, even in the usual case of the two
having nothing to do with each other.

This diff removes all import_module declarations from the packages,
and replaces them with import_module declarations in the modules that need
them. This includes only a SUBSET of their child modules and of the non-child
modules that import them.
2015-11-13 15:03:20 +11:00
Zoltan Somogyi
656493dfdf Use separate types for the status of different entity kinds.
We used the old import_status type to represent the status of six different
kinds of entities:

- types
- insts
- modes
- typeclasses
- instances
- predicates

even though some statuses that made sense for one kind of entity didn't for
another another (e.g. predicates can be pseudo imported/exported, but the
other five kinds of entities cannot).

Create the new types type_status, inst_status, ..., pred_status to represent
the status of these entities in the HLDS. For now, these are just wrappers
around the renamed old_import_status type, but I plan to replace them with
status types that *are* specialized to the applicable kind of entity,
along the lines of compiler/notes/status_proposal. This is a necessary
first step towards that proposal.

compiler/status.m:
    Define the six new entity-kind-specific status types, and replicate
    the test predicates that used to work on the import_status type
    to work on these instead.

    Define a status type, item_mercury_status, that contains just the info
    that is common to all entities in an item block, for use during
    the process of adding items to the HLDS.

    Move the predicates that converted section markers to statuses
    from here to make_hlds_passes.m, since that is the only place
    where they are used, or can be used.

    Move the combine_status predicate here from add_type.m, since
    it is needed for combining the statuses of other kinds of entities
    as well, not just types.

compiler/hlds_data.m:
    Change the HLDS types that record the information we have about
    types, du type fields, insts, modes, typeclasses and instances
    to have kind-specific status fields, instead of the old generic
    import_status type.

    Change the prefix on the field names of the hlds_instance_defn type
    to avoid a name clash, and to make them more meaningful.

    Change the prefix on the field names of the hlds_class_defn type
    to make them more meaningful.

compiler/hlds_pred.m:
    Change the HLDS type that records the information we have about predicates
    to have a kind-specific status field, instead of the old generic
    import_status type.

    Update the predicates that test predicate statuses accordingly.

compiler/hlds_module.m:
    Change the HLDS types that record the information we have about
    type constructors to be type_status, not the old generic import_status.

compiler/make_hlds_passes.m:
    As we process each item block, pass along an item_mercury_status
    instead of an import_status. The code used to use only a subset
    of the possible values of the import_status type, since we can never say
    that all the entities in an item block are e.g. pseudo-exported.
    An item_mercury_status has just the information we actually *know*
    about the item block as a whole. We convert the item_mercury_status
    to a kind-specific status if and when we need to, but for several purposes,
    the item_mercury_status is enough on its own.

    In a few cases, add a new predicate to do this conversion.

    Pass the need_qualifier flag separately from the status. It is needed
    in only a few places, but this was not apparent when we always passed it
    around paired with the import_status.

    Move the predicates that converted section markers to statuses
    to here from status.m, since here is the only place where they are used,
    or can be used.

compiler/add_class.m:
    Convert the statuses of typeclasses and instances to the statuses
    of the predicates implementing their virtual and concrete methods.

compiler/check_typeclass.m:
    Simplify some over-complex code.

compiler/add_special_pred.m:
    Convert the statuses of types to the statuses of the predicates
    implementing their unify, index, compare and solver init operations.
    Note some places where the process of this conversion is (to say the least)
    unclear and undocumented.

compiler/hlds_out_util.m:
    Provide utility predicates to print all the new kinds of statuses.
    These replace the old predicate that did the same in hlds_out_pred.m,
    but printing e.g. type statuses in hlds_out_pred doesn't seem right.

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

    Consistently use switches on the booleans returned by xxx_status_to_write,
    instead wrapping a semidet predicate around it and calling that.
    The switches yield code that is both smaller and more maintainable.

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

    Delete a simple wrapper predicate that was used only in one place.
    That place now does the wrapping itself.

compiler/qual_info.m:
    Replace the import_status field in the qual_info with a simple
    is_opt_imported/is_not_opt_imported flag, since that was the only
    thing we used the import_status field for.

compiler/accumulator.m:
compiler/add_clause.m:
compiler/add_foreign_enum.m:
compiler/add_foreign_proc.m:
compiler/add_mode.m:
compiler/add_mutable_aux_preds.m:
compiler/add_pragma.m:
compiler/add_pragma_tabling.m:
compiler/add_pragma_type_spec.m:
compiler/add_pred.m:
compiler/add_solver.m:
compiler/add_type.m:
compiler/base_typeclass_info.m:
compiler/ctgc.util.m:
compiler/dead_proc_elim.m:
compiler/dep_par_conj.m:
compiler/dependency_graph.m:
compiler/det_report.m:
compiler/elds_to_erlang.m:
compiler/equiv_type_hlds.m:
compiler/erl_code_gen.m:
compiler/export.m:
compiler/float_regs.m:
compiler/higher_order.m:
compiler/hlds_code_util.m:
compiler/hlds_out_module.m:
compiler/hlds_out_pred.m:
compiler/inst_check.m:
compiler/lambda.m:
compiler/lco.m:
compiler/make_hlds.m:
compiler/make_hlds_warn.m:
compiler/make_tags.m:
compiler/ml_proc_gen.m:
compiler/ml_type_gen.m:
compiler/mode_errors.m:
compiler/oisu_check.m:
compiler/par_loop_control.m:
compiler/polymorphism.m:
compiler/post_term_analysis.m:
compiler/post_typecheck.m:
compiler/prop_mode_constraints.m:
compiler/recompilation.usage.m:
compiler/simplify_proc.m:
compiler/smm_common.m:
compiler/special_pred.m:
compiler/ssdebug.m:
compiler/status.m:
compiler/stm_expand.m:
compiler/structure_reuse.analysis.m:
compiler/structure_reuse.direct.m:
compiler/structure_reuse.indirect.m:
compiler/structure_reuse.versions.m:
compiler/structure_sharing.analysis.m:
compiler/structure_sharing.domain.m:
compiler/superhomogeneous.m:
compiler/table_gen.m:
compiler/term_constr_initial.m:
compiler/term_constr_main.m:
compiler/termination.m:
compiler/trace_params.m:
compiler/type_class_info.m:
compiler/type_constraints.m:
compiler/type_ctor_info.m:
compiler/typecheck.m:
compiler/typecheck_info.m:
compiler/typeclasses.m:
compiler/unify_proc.m:
compiler/untupling.m:
compiler/unused_args.m:
compiler/unused_imports.m:
compiler/xml_documentation.m:
    Conform to the changes above.
2015-09-12 09:07:45 +10:00
Zoltan Somogyi
ea094b5bb7 Make the import_status type part of the HLDS.
The import_status type was defined in parse_tree.status.m, but it is
not actually used in the parse_tree package. It is used, extensively,
in the hlds package.

compiler/status.m:
compiler/prog_item.m:
compiler/prog_data.m:
    Move the parts of status.m that *are* needed in the parse_tree package
    to modules in that package. The section markers and the import_locn type
    are moved to prog_item.m, while the need_qualifier type is moved to
    prog_data.m.

compiler/parse_tree.m:
compiler/hlds.m:
    Switch the status.m module from being in the parse_tree package
    to being in the hlds package.

compiler/notes/compiler_design.html:
    Document the switch.

compiler/*.m:
    Update import_module declarations as needed after the above change.

    In some places, import parse_tree.prog_item as well as hlds.status,
    even if we are only intested in statuses, because the import_locn type,
    which part of some statuses, *is* used in the parse_tree package,
    and must therefore be defined there. These undesirable dependencies
    will go away when we implement the proposal for purpose-specific status
    types.
2015-09-09 01:47:08 +10:00
Zoltan Somogyi
04dec8c205 Carve vartypes.m, prog_detism.m and prog_rename.m out of prog_data.m.
Besides defining most of the types representing the smaller parts of
parse trees (parts smaller than items), prog_data.m also has many utility
predicates that operate on values of these types. Carve the three substantial
clusters of predicates out of prog_data.m, and move them into their own
modules, which are each imported by fewer modules than prog_data.m itself.

compiler/vartypes.m:
    New module containing the vartypes type and the predicates that operate
    on it. The new module has *much* better cohesion than the old prog_data.m.

    The vartypes type does not appear in any parse tree; it is used only
    in the HLDS. So make vartypes.m part of the hlds.m package, not
    parse_tree.m.

    Move three predicates that perform renamings and substitutions on vartypes
    here from prog_type_subst.m, since the latter is part of the parse_tree.m
    package, and thus doesn't have access to hlds.vartypes. Make private
    the service predicate that these three moved predicates used to rely on,
    since it has no other callers.

compiler/prog_detism.m:
    New module containing utility predicates that operate on determinisms
    and determinism components.

compiler/prog_rename.m:
    New module containing utility predicates that rename variables in
    various data structures.

compiler/prog_data.m:
    Remove the stuff now in the three new modules.

compiler/prog_type_subst.m:
    Remove the three predicates now in vartypes.m.

compiler/mercury_to_mercury.m:
    Delete an unneded predicate, which was the only part of this module
    that referred to vartypes.

compiler/prog_type.m:
compiler/builtin_lib_types.m:
compiler/type_util.m:
    Move some utility predicates that refer to vartypes from prog_type.m
    and builtin_lib_types.m (both part of parse_tree.m) to type_util.m
    (part of check_hlds.m).

compiler/parse_tree.m:
compiler/hlds.m:
compiler/notes/compiler_design.html:
    Mention the new modules.

compiler/accumulator.m:
compiler/add_class.m:
compiler/add_clause.m:
compiler/add_foreign_proc.m:
compiler/add_heap_ops.m:
compiler/add_pragma_type_spec.m:
compiler/add_pred.m:
compiler/add_trail_ops.m:
compiler/arg_info.m:
compiler/bytecode_gen.m:
compiler/call_gen.m:
compiler/clause_to_proc.m:
compiler/closure_analysis.m:
compiler/code_info.m:
compiler/code_loc_dep.m:
compiler/common.m:
compiler/complexity.m:
compiler/const_prop.m:
compiler/constraint.m:
compiler/continuation_info.m:
compiler/coverage_profiling.m:
compiler/cse_detection.m:
compiler/ctgc.datastruct.m:
compiler/ctgc.util.m:
compiler/deep_profiling.m:
compiler/deforest.m:
compiler/delay_construct.m:
compiler/delay_partial_inst.m:
compiler/dep_par_conj.m:
compiler/det_analysis.m:
compiler/det_report.m:
compiler/det_util.m:
compiler/disj_gen.m:
compiler/equiv_type_hlds.m:
compiler/erl_call_gen.m:
compiler/erl_code_gen.m:
compiler/erl_code_util.m:
compiler/exception_analysis.m:
compiler/float_regs.m:
compiler/follow_code.m:
compiler/follow_vars.m:
compiler/format_call.m:
compiler/goal_expr_to_goal.m:
compiler/goal_path.m:
compiler/goal_store.m:
compiler/goal_util.m:
compiler/headvar_names.m:
compiler/hhf.m:
compiler/higher_order.m:
compiler/hlds_clauses.m:
compiler/hlds_goal.m:
compiler/hlds_llds.m:
compiler/hlds_out_goal.m:
compiler/hlds_out_module.m:
compiler/hlds_out_pred.m:
compiler/hlds_pred.m:
compiler/hlds_rtti.m:
compiler/inlining.m:
compiler/inst_util.m:
compiler/instmap.m:
compiler/intermod.m:
compiler/interval.m:
compiler/lambda.m:
compiler/lco.m:
compiler/live_vars.m:
compiler/liveness.m:
compiler/lookup_switch.m:
compiler/make_goal.m:
compiler/mark_tail_calls.m:
compiler/ml_accurate_gc.m:
compiler/ml_code_gen.m:
compiler/ml_code_util.m:
compiler/ml_disj_gen.m:
compiler/ml_gen_info.m:
compiler/ml_lookup_switch.m:
compiler/ml_proc_gen.m:
compiler/ml_unify_gen.m:
compiler/mode_constraints.m:
compiler/mode_info.m:
compiler/mode_util.m:
compiler/modecheck_call.m:
compiler/modecheck_conj.m:
compiler/modecheck_goal.m:
compiler/modecheck_unify.m:
compiler/modecheck_util.m:
compiler/modes.m:
compiler/par_loop_control.m:
compiler/pd_info.m:
compiler/pd_util.m:
compiler/polymorphism.m:
compiler/post_typecheck.m:
compiler/prog_rep.m:
compiler/prop_mode_constraints.m:
compiler/purity.m:
compiler/qual_info.m:
compiler/quantification.m:
compiler/rbmm.points_to_graph.m:
compiler/rbmm.points_to_info.m:
compiler/rbmm.region_liveness_info.m:
compiler/rbmm.region_transformation.m:
compiler/saved_vars.m:
compiler/set_of_var.m:
compiler/simplify_goal_call.m:
compiler/simplify_goal_conj.m:
compiler/simplify_goal_disj.m:
compiler/simplify_goal_ite.m:
compiler/simplify_goal_scope.m:
compiler/simplify_goal_switch.m:
compiler/simplify_goal_unify.m:
compiler/simplify_info.m:
compiler/simplify_proc.m:
compiler/size_prof.m:
compiler/ssdebug.m:
compiler/stack_alloc.m:
compiler/stack_layout.m:
compiler/stack_opt.m:
compiler/stm_expand.m:
compiler/store_alloc.m:
compiler/structure_reuse.analysis.m:
compiler/structure_reuse.direct.choose_reuse.m:
compiler/structure_reuse.direct.detect_garbage.m:
compiler/structure_reuse.indirect.m:
compiler/structure_reuse.lbu.m:
compiler/structure_reuse.lfu.m:
compiler/structure_sharing.analysis.m:
compiler/structure_sharing.domain.m:
compiler/switch_detection.m:
compiler/table_gen.m:
compiler/tabling_analysis.m:
compiler/term_constr_build.m:
compiler/term_constr_initial.m:
compiler/term_constr_util.m:
compiler/term_pass1.m:
compiler/term_traversal.m:
compiler/term_util.m:
compiler/trace_gen.m:
compiler/trailing_analysis.m:
compiler/try_expand.m:
compiler/tupling.m:
compiler/type_assign.m:
compiler/type_constraints.m:
compiler/typecheck.m:
compiler/typecheck_errors.m:
compiler/unify_gen.m:
compiler/unify_proc.m:
compiler/unique_modes.m:
compiler/unneeded_code.m:
compiler/untupling.m:
compiler/unused_args.m:
compiler/var_locn.m:
    Conform to the above changes, mostly by importing some of the
    three new modules as well as, or instead of, prog_data.m.
2015-08-09 19:02:12 +10:00
Zoltan Somogyi
b7a91d10b3 Bring the style of accumulator.m up-to-date. 2015-07-23 05:52:50 +10:00
Zoltan Somogyi
f2043fc9bd Replace the item list with more structured ASTs.
The parts of the compiler that run before the HLDS is constructed used to use
a raw list of items to represent source files (.m), interface files (.int0,
.int3, .int2 and .int) and optimization files (.opt, and .trans_opt).
These lists had structure, but this structure was implicit, not explicit,
and its invariants were never really documented.

This diff changes that. It replaces the item list with FIVE separate types.

Three of these each represent the unprocessed content of one file:

- parse_tree_int represents the contents of one interface file;
- parse_tree_opt represents the contents of one optimization file;
- parse_tree_src represents the contents of one source file.

Two of these each represent the processed contents of one or more files:

- raw_compilation_unit represents the contents of one module in a source file.
  (The source file may contain several nested modules; the compilation unit
  represents just one.)
- aug_compilation_unit represents the contents of one module in a source file,
  just like raw_compilation_unit, but it is augmented with the contents of the
  interface and optimization files of the other modules imported (directly or
  indirectly) by the original module.

These five separate concepts all used to be represented by the same type,
list(item), but different invariants applied to the structure of those lists.
The most important of those invariants at least are now explicit in the types.
I think it is entirely possible that there are other invariants I haven't
discovered and documented (for example, .int3 files must have stricter
invariants on what can appear in them than .int files), but discovering
and documenting these should be MUCH easier after this change.

I have marked many further opportunities for improvements with "XXX ITEM_LIST".
Some of these include moving code between modules, and the creation of new
modules. However, I have left acting on those XXXs until later, in order to
keep the size of this diff down as much as possible, for easier reviewing.

compiler/prog_item.m:
    Define the five new AST types described above, and utility predicates
    that operate on them.

    In the rest of this change, I tried, as much as possible, to change
    predicates that used to take item lists as arguments to make them change
    one of these types instead. In many cases, this required putting
    the argument lists of those predicates into a more consistent order.
    (Often, predicates that operated on the contents of the module
    took the name of the module and the list of items in the module
    not just as separate arguments, but as separate arguments that
    weren't even next to each other.)

    Define types that identify the different kinds of interface and
    optimization files (.int, .int2 etc). These replace the string suffixes
    we used to use to identify file types. Predicates that used to take strings
    representing suffixes as arguments now have to specify whether they can
    handle all these file types (source, interface and optimization),
    or just (e.g.) all interface file types.

    We used to have items corresponding to `:- module' and `:- end_module'.
    Delete these; this information is now implicit in the structure of the
    relevant AST. The parser handles the corresponding terms as markers,
    not items; these markers are live only during parsing.

    We used to have module_defns corresponding to `:- interface' and
    `:- implementation'. Delete these; this information is now also implicit
    in the structure of the relevant AST. Delete also, for the same reason,
    the module_defns used to mark the starts of sublists in the overall lists
    of items whose items came from the interface files or optimization files
    of other modules. The former are now markers during parsing. The latter
    are never parsed, but are created directly, after parsing has been done.

    Delete the pragma type for `:- pragma source_file'. This is never
    needed later; it is now a marker during parsing.

    Change the internal representation of `:- import' and `:- use'.
    It used to store a list of module names, but that list was an actual list
    only during parsing; after that, it always had exactly one element.
    It now stores one module name, and the parser has a mechanism to convert
    one read-in term to more than one item, for use with terms such as
    `:- import_module a, b'.

    Delete the internal representation of `:- export', which was never
    implemented, since if it IS ever implemented, it will almost certainly
    be in a different form, which will need different support.

    Document some further opportunities for simplification, later.
    (This diff is already more than big enough.)

compiler/prog_io_item.m:
    Rewrite the top-level part of this module. Instead of returning an item
    for every parsed term, distinguish between parsing items that end up
    in item lists inside ASTs, and parsing markers that end up creating
    the STRUCTURE of those ASTs.

compiler/prog_io.m:
    Rewrite the meat of this module. Instead of reading in a simple item list,
    we now have to read in three different parse trees with three different
    grammars, each of which is more complex than a simple list.

compiler/read_modules.m:
    We used to have a map that mapped file names to the contents of those
    files. We now need three separate maps, for interface files, optimization
    files and source files, due to their separate types.
    (We don't actually use the map for optimization files, which seems
    to be a potential performance bug. The root cause of that problem
    us that while intermod.m and the grab_*modules part of modules.m do
    similar jobs, they don't use the same mechanisms.)

    Replace the read_module predicate with the predicates read_module_src
    and read_module_int, since these now return different types.

    To avoid having to create AST-type-specialized variants of
    read_module_ignore_errors and read_module_if_changed, give each of
    read_module_{src,int} arguments that optionally tell them to ignore errors
    and/or to read the module only if changed (though the "and" part of
    "and/or" should not be needed.) These options already existed, but
    they weren't exported.

compiler/timestamp.m:
    Define the type we use for this option in read_modules.

compiler/status.m:
    New module, containing mostly

    - stuff carved out of hlds_pred.m, which defines the import_status type,
      and the predicates that operate on it;
    - stuff carved out of make_hlds_passes.m, which defines the item_status
      type and the predicates that operate on that; and
    - stuff carved out prog_data.m, which defines the section (now
      module_section) and import_locn types.

    It also contains the new section kinds we now use to represent item blocks
    that were imported from interface and optimization files.

compiler/parse_tree.m:
compiler/notes/compiler_design.html:
    Add status.m to the parse_tree package.

compiler/hlds_pred.m:
compiler/prog_data.m:
    Remove the stuff now in status.m.

compiler/error_util.m:
    Provide a mechanism to control the order of messages with respect to
    ALL other messages, not just those that also specify ordering.

compiler/mercury_to_mercury.m:
    Provide predicates for printing out parse_tree_* and *_compilation_unit,
    since printing out a simple item list is no longer enough for debugging.

    Pretty-print type definitions nicely.

    Replace a boolean with a purpose-specific enum.

compiler/modules.m:
    Rewrite virtually all this module to make it work on the new AST
    representations. Generate more detailed error messages for duplicate
    module inclusions. Note lots of possibilities for further improvements,
    including in the documentation. Mark places I am still not sure about,
    especially places where I am not sure *why* the code is doing
    what it is doing.

compiler/module_imports.m:
    This module stores the data structure in which we accumulate the stuff
    imported into a compilation unit, i.e. it is in these data structures
    that a raw_compilation_unit becomes an aug_compilation_unit. Modify
    the data structure and the predicates that operate on it to work on the
    new AST representations, not on an (apparently) simple list of items.

    Avoid ambiguities by adding a prefix to field names.

    Add some convenience predicates.

compiler/module_qual.m:
    Perform module qualification on both raw lists of items (for use when
    generating .int3 files) but also on item blocks (for use pretty much
    in every other situation).

    Generate warnings about module imports that are unnecessarily in the
    module interface using the module's context (the context of the `:- module'
    declaration), not line 1 of the relevant file.

compiler/prog_io_error.m:
    Split some error categories more finely, since some error kinds here
    actually used to be reported for more than one distinct situation.

compiler/prog_io_util.m:
    Provide utility predicates that operate on nonempty lists.

compiler/recompilation.version.m:
    Make the comparison of the old and new contents of the interface file
    work on two parse_tree_ints, not on two raw sequences of items.

    Delete a boolean option that was always `yes', never 'no'.

compiler/recompilation.m:
    Turn some functions into predicates to allow the use of state variable
    notation.

    Avoid ambiguities by adding a prefix to field names.

compiler/write_module_interface_files.m:
    Besides updating the code in this module to work on the new parse tree
    representations, also use cords instead of reversed lists in several cases.
    Note many possibilities for further improvements.

library/list.m:
    Move the type one_or_more here from the compiler directory, since
    we now use it in more than one compiler module, and this is its natural
    home.

mdbcomp/sym_name.m:
    Rename "match_sym_name" to "partial_sym_name_matches_full", since this
    better describes its job.

    Add a det version of sym_name_get_module_name.

compiler/equiv_type.m:
    Rename some types to make them more expressive.

compiler/accumulator.m:
compiler/add_class.m:
compiler/add_foreign_enum.m:
compiler/add_foreign_proc.m:
compiler/add_mode.m:
compiler/add_pragma.m:
compiler/add_pragma_tabling.m:
compiler/add_pred.m:
compiler/add_solver.m:
compiler/add_special_pred.m:
compiler/add_type.m:
compiler/assertion.m:
compiler/base_typeclass_info.m:
compiler/check_typeclass.m:
compiler/ctgc.util.m:
compiler/dead_proc_elim.m:
compiler/dep_par_conj.m:
compiler/dependency_graph.m:
compiler/deps_map.m:
compiler/det_report.m:
compiler/elds_to_erlang.m:
compiler/equiv_type_hlds.m:
compiler/erl_code_gen.m:
compiler/export.m:
compiler/format_call.m:
compiler/higher_order.m:
compiler/hlds_data.m:
compiler/hlds_module.m:
compiler/hlds_out_pred.m:
compiler/inst_check.m:
compiler/intermod.m:
compiler/item_util.m:
compiler/lambda.m:
compiler/lco.m:
compiler/make.module_dep_file.m:
compiler/make_hlds.m:
compiler/make_hlds_error.m:
compiler/make_hlds_passes.m:
compiler/make_tags.m:
compiler/mercury_compile.m:
compiler/ml_proc_gen.m:
compiler/ml_type_gen.m:
compiler/mode_errors.m:
compiler/oisu_check.m:
compiler/par_loop_control.m:
compiler/polymorphism.m:
compiler/post_term_analysis.m:
compiler/post_typecheck.m:
compiler/pred_table.m:
compiler/prog_io_dcg.m:
compiler/prog_io_find.m:
compiler/prog_io_pragma.m:
compiler/prog_io_sym_name.m:
compiler/prog_io_type_defn.m:
compiler/prog_io_typeclass.m:
compiler/prop_mode_constraints.m:
compiler/push_goals_together.m:
compiler/qual_info.m:
compiler/recompilation.check.m:
compiler/recompilation.usage.m:
compiler/simplify_proc.m:
compiler/smm_common.m:
compiler/special_pred.m:
compiler/ssdebug.m:
compiler/stm_expand.m:
compiler/structure_reuse.analysis.m:
compiler/structure_reuse.direct.m:
compiler/structure_reuse.indirect.m:
compiler/structure_reuse.versions.m:
compiler/structure_sharing.analysis.m:
compiler/structure_sharing.domain.m:
compiler/table_gen.m:
compiler/term_constr_initial.m:
compiler/term_constr_main.m:
compiler/termination.m:
compiler/trace_params.m:
compiler/trans_opt.m:
compiler/type_class_info.m:
compiler/type_ctor_info.m:
compiler/typecheck.m:
compiler/typecheck_errors.m:
compiler/typecheck_info.m:
compiler/unify_proc.m:
compiler/untupling.m:
compiler/unused_args.m:
compiler/unused_imports.m:
compiler/write_deps_file.m:
compiler/xml_documentation.m:
    Conform to the changes above.

tests/hard_coded/higher_order_func_test.m:
tests/hard_coded/higher_order_syntax.m:
    Avoid a warning about importing a module in the interface, not the
    implementation.

tests/invalid/after_end_module.err_exp:
tests/invalid/any_mode.err_exp:
tests/invalid/bad_end_module.err_exp:
tests/invalid/bigtest.err_exp:
tests/invalid/bug113.err_exp:
tests/invalid/duplicate_modes.err_exp:
tests/invalid/errors.err_exp:
tests/invalid/errors1.err_exp:
tests/invalid/errors2.err_exp:
tests/invalid/funcs_as_preds.err_exp:
tests/invalid/inst_list_dup.err_exp:
tests/invalid/invalid_main.err_exp:
tests/invalid/missing_interface_import2.err_exp:
tests/invalid/no_exports.err_exp:
tests/invalid/occurs.err_exp:
tests/invalid/predmode.err_exp:
tests/invalid/prog_io_erroneous.err_exp:
tests/invalid/type_inf_loop.err_exp:
tests/invalid/typeclass_missing_det_3.err_exp:
tests/invalid/typeclass_test_11.err_exp:
tests/invalid/types.err_exp:
tests/invalid/undef_inst.err_exp:
tests/invalid/undef_mode.err_exp:
tests/invalid/undef_type.err_exp:
tests/invalid/unicode1.err_exp:
tests/invalid/unicode2.err_exp:
tests/invalid/vars_in_wrong_places.err_exp:
tests/warnings/unused_import.exp:
tests/warnings/unused_interface_import.exp:
    Update the expected outputs in the invalid and warnings directories
    to account for one or more of the following five changes.

    Error messages that warn about a module not exporting anything
    used to always refer to line 1 of the module's source file.
    Now expect these messages to refer to the actual context of the module,
    which is the context of its `:- module' declaration.

    Expect a similarly updated context for messages that warn about
    unnecessarily importing modules in the interface, not in the
    implementation.

    Expect a similarly updated context for messages that warn about
    importing a module via both `:- import_module' and `:- use_module'.

    For the modules that follow the `:- module' declaration directly with code,
    also expect an error message about the missing section marker.

    For modules that have terms after the `:- end_module' declaration,
    replace "end_module" with "`:- end_module'" in the error message.

tests/invalid/func_class.{m,err_exp}:
    New test case. It is a copy of the old tests/valid/func_class.m, which
    is missing more than one module marker. The expected output is what I think
    we should generate. The test case currently fails, because we currently
    print only a subset of the expected errors. I am pretty sure the reason
    for that is that old code I have not modified simply throws away the
    missing error messages. Fixing this is work for the near future.

tests/invalid/Mmakefile:
    Enable the new test case.

tests/misc_tests/pretty_print_test.exp:
    Expect the pretty-printed output to use four-space indentation,
    per our current style guide, since the compiler now generates such output.

tests/misc_tests/pretty_print_test.m:
    Clean up the source code of the test as well.

tests/valid/complicated_unify.m:
tests/valid/det_switch.m:
tests/valid/easy_nondet_test.m:
tests/valid/error.m:
tests/valid/func_class.m:
tests/valid/func_int_bug_main.m:
tests/valid/higher_order.m:
tests/valid/higher_order2.m:
tests/valid/implied_mode.m:
tests/valid/indexing.m:
tests/valid/multidet_test.m:
tests/valid/nasty_func_test.m:
tests/valid/semidet_disj.m:
tests/valid/stack_alloc.m:
tests/valid/switches.m:
    Add missing section markers to these modules. They used to follow
    the `:- module' declaration directly with code.
2015-07-21 04:06:52 +10:00
Zoltan Somogyi
4e3af446ef Give some verbose error explanations only once.
compiler/error_util.m:
    Some of the messages we print if --verbose-errors are enabled just explain
    what an always-printed error message means. If a compiler invocation
    reports several instances of an error, the explanation is useful
    only the first time. This diff provides a mechanism for printing
    such verbose messages only once per invocation of write_error_specs.

compiler/*.m:
    Specify verbose_once for verbose error message components which are
    (a) not specific to the specific instance of the error they are generated
    for, and (b) whose usefulness/size ratio is not high enough. Part (b)
    means that it is ok to repeatedly print a single-line reminder,
    but not a 20-line missive that reads like an extract from the
    reference manual.

    In one case, make an error message clearer.

tests/invalid/*.err_exp:
tests/warnings/*.exp:
    Expect the new, slimmed-down output.
2015-02-19 12:38:07 +11:00
Zoltan Somogyi
8dc5a0071c Miscellaneous cleanups.
Just fixes to comments, better variable and predicate names, and the like.
No algorithmic changes.
2015-01-02 16:15:30 +11:00
Zoltan Somogyi
fe785c668b Consistently use set.is_empty and set.is_non_empty.
compiler/*.m:
deep_profiler/*.m:
    As above.

library/set.m:
library/set_bbbtree.m:
library/set_ctree234.m:
library/set_ordlist.m:
library/set_tree234.m:
library/set_unordlist.m:
    Add is_non_empty to the set modules that did not already have it.
    (Some did, some didn't.)

    Make the documentation of empty, is_empty, non_empty and is_non_empty
    consistent.
2014-11-04 23:18:43 +11:00
Peter Wang
f0032d3ae3 Modify code for stricter mode checking.
The following changes are necessary to compile the code following an
upcoming change to the mode checker.  Some of them are mode errors.

browser/declarative_oracle.m:
	The result of `query_oracle_kb' should be specific
	to avoid mode errors in callers.

compiler/accumulator.m:
	Help the compiler infer the declared inst.

compiler/mode_robdd.tfeirn.m:
	`zero' must be declared to return a normalised tfeirn value to
	avoid mode errors.  Change `one' for symmetry.

	`var_restrict_true' and `var_restrict_false' may return
	unnormalised tfeirn values (judging by the code).

	Modify `normalise' to help the compiler infer
	the declared inst.

compiler/tupling.m:
deep_profiler/autopar_find_best_par.m:
	Delete final insts that the compiler cannot verify.

library/tree234.m:
	Help the mode checker out using an explicit switch.

tests/hard_coded/bitmap_test.m:
tests/hard_coded/bitmap_tester.m:
	Add missing modes.
2014-10-10 16:13:34 +11:00
Zoltan Somogyi
500948d549 Break up mdbcomp/prim_data.m. The new modules have much better cohesion.
mdbcomp/sym_name.m:
    New module, containing the part of the old prim_data.m that
    dealt with sym_names.

mdbcomp/builtin_modules.m:
    New module, containing the part of the old prim_data.m that
    dealt with builtin modules.

mdbcomp/prim_data.m:
    Remove the things that are now in the two new modules.

mdbcomp/mdbcomp.m:
deep_proiler/Mmakefile:
slice/Mmakefile:
    Add the two new modules.

browser/*.m:
compiler/*.m:
deep_proiler/*.m:
mdbcomp/*.m:
slice/*.m:
    Conform to the above changes.
2014-09-02 05:20:23 +02:00