Commit Graph

55 Commits

Author SHA1 Message Date
Zoltan Somogyi
f355497087 Delete include context maps from parse_tree_int[012].
compiler/prog_item.m:
    We used to record information about include declarations
    in parse_tree_int[012] in two forms:

    - as a pair of maps from module names to contexts (one each for
      includes in the interface and implementation sections), and
    - as a single map from module names to an include_module_info, which
      recorded the section of its appearance along with its context.

    The second of these data structures is derived from the first,
    in a process that can result in the generation of diagnostic messages.
    In the absence of any issues reported by these diagnostics, the two forms
    contain the same information.

    Avoid this redundancy by keeping only the second form in the parse trees
    of .int0, .int and .int2 files. (.int3 files cannot contain include_module
    declarations.)

    Since .int2 files may contain include_module declarations only in
    the interface section, change the representation of the second form
    to a type that expresses this invariant: int_include_module_map,
    which is a subtype of the existing type include_module_map.

compiler/comp_unit_interface.m:
compiler/convert_parse_tree.m:
compiler/equiv_type.m:
compiler/get_dependencies.m:
compiler/grab_modules.m:
compiler/make_hlds_separate_items.m:
compiler/module_qual.collect_mq_info.m:
compiler/parse_tree_out.m:
compiler/recompilation.check.m:
compiler/recompilation.version.m:
    Conform to the change above.

compiler/item_util.m:
    Add a utility predicate for use by new code above.
2023-01-22 19:01:42 +11:00
Zoltan Somogyi
5ae7d25740 Delete import/use context maps from parse_tree_int[012].
compiler/prog_item.m:
    We used to record information about import and use declarations
    in parse_tree_int[012] in two forms:

    - as a quartet of maps from module names to contexts (one each for
      int imports, int uses, imp imports and imp uses), and
    - as a single map from module names to a section_import_and_or_use,
      which recorded the section and kind (import or use) of its appearance
      along with its one context, except for the case of modules that have
      an use_module declaration in the interface section and an import_module
      declaration in the implementation section.

    The second of these data structures is derived from the first,
    in a process that can result in the generation of diagnostic messages.
    In the absence of any issues reported by these diagnostics, the two forms
    contain the same information.

    Avoid this redundancy by keeping only the second form in the parse trees
    of .int0, .int and .int2 files. (For .int3 files, which can contain
    only import_modules, and only in the interface section, this redundancy
    has not been present even before now.)

    Since .int and .int2 files may contain only use_module declarations
    and not import_module declarations, change the representation of the
    second form to a type that expresses this invariant: the new type
    section_use_map, which is a subtype of the existing type
    section_import_and_or_use_map.

    For .int2 files, we could use an even tighter type right now, but
    a fix for Mantis bug #563 would have to undo such a change, so
    don't bother.

compiler/comp_unit_interface.m:
    Delete the code that used to construct the first form above
    for these interface file kinds. Conform to the changes above.

compiler/convert_parse_tree.m:
compiler/equiv_type.m:
compiler/get_dependencies.m:
compiler/grab_modules.m:
compiler/make_hlds_separate_items.m:
compiler/module_qual.collect_mq_info.m:
compiler/parse_tree_out.m:
compiler/recompilation.check.m:
compiler/recompilation.version.m:
    Conform to the changes above.

compiler/item_util.m:
    Add new, specialized versions of existing utility predicates
    to make that conformance possible.
2023-01-21 21:31:00 +11:00
Zoltan Somogyi
faf9ebf5e3 Don't provide for implicit imports in .intN parse trees.
compiler/prog_item.m:
    The ptiN_import_use_map fields in the representations of .int0, .int
    and .int2 files had the same type as the ptms_import_use_map field
    in the parse trees of .m files, which is where they were derived from.
    However, while the ptms_import_use_map field needs to be able to represent
    implicit imports, the parse trees of .int0, .int and .int2 files
    should never include any implicit imports, and in fact any implicit
    imports in these fields were already ignored.

    Encode the invariant that interface files never include implicit imports
    in the types of these fields.

compiler/comp_unit_interface.m:
    Discard the implicit part of the source file's import_and_or_use_map
    when computing the contents of .int0, .int and .int2 files.

compiler/item_util.m:
    Provide the facilities used by the updated code in the modules above.

compiler/convert_parse_tree.m:
compiler/grab_modules.m:
compiler/make_hlds_separate_items.m:
    Conform to the changes above.
2023-01-21 06:38:17 +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
a32d6a16f4 Add the format_call pragma to the language.
doc/reference_manual.texi:
NEWS:
    Document and announce the new pragma.

compiler/prog_data_pragma.m:
compiler/prog_item.m:
    Provide a representation for the new pragma. The part that ends up
    being referred to from the HLDS goes into prog_data_pragma.m,
    the part that is not needed once the HLDS has been constructed
    goes into prog_item.m.

compiler/hlds_pred.m:
    Add a slot to pred_infos for info from the new pragma.

    Fix a bug in the comment on marker_has_format_call.

compiler/add_pragma.m:
    Add the information in these pragmas to the HLDS.

compiler/check_pragma_format_call.m:
    A new module to check the validity of format_call pragmas.
    These checks test whether the arguments named in such pragmas
    have the expected types and modes, which means that
    the check must be done after both type and mode checking.

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

compiler/hlds_module.m:
    Add a field to the module_info that records the set of pred_ids
    that have format_call pragmas.

compiler/mercury_compile_front_end.m:
    Invoke the check_pragma_format_call pass *provided* that
    the new field in the module_info says it has any pragmas to check.

compiler/parse_pragma.m:
    Add code to parse the new pragma.

compiler/format_call.m:
    Check calls to predicates and functions with the new pragma
    the same way as we check calls to string.format, io.format,
    and stream.string_writer.format.

    This required separating the code that checked calls to such predicates
    from the code that optimized calls to such predicates, since

    - a predicate or function with a format_call pragma that specifies
      more than one argument pair has to have its correctness checked
      for each pair, and

    - a predicate or function with a format_call pragma does not actually
      do any formatting, so that formatting cannot be optimized.

    Fix an old bug, where we included the function result in the function's
    reported arity, which meant that an error message could mention a call
    to a nonexistent function. As part of that fix, the error message
    now specifies whether it is complaining about a call to a predicate
    or a function.

    Change the exported interface of this module a bit
    in order to allow the factoring out of repeated code.

compiler/parse_string_format.m:
    Separate the parsing of format strings from their optimization,
    again because calls to predicates and functions with format_call
    pragmas need to be checked but cannot be optimized.

compiler/polymorphism.m:
    Record the effect on argument numbers of any type_info and/or
    typeclass_info arguments added by this pass.

compiler/convert_parse_tree.m:
compiler/det_analysis.m:
compiler/direct_arg_in_out.m:
compiler/equiv_type.m:
compiler/get_dependencies.m:
compiler/hlds_out_pred.m:
compiler/item_util.m:
compiler/module_qual.qualify_items.m:
compiler/parse_tree_out_pragma.m:
compiler/prog_item_stats.m:
compiler/recompilation.version.m:
compiler/simplify_proc.m:
    Conform to the changes above.

tests/invalid/bad_format_call.{m,err_exp}:
    A new test case to see whether check_pragma_format_call.m detects
    and reports invalid format_call pragmas as expected.

tests/warnings/format_call_warning.{m,exp}:
tests/warnings/format_call_warning_helper.m:
    A new test case to see whether we generate the expected set of error
    messages for incorrect calls to a predicate with a format_call pragma.

tests/invalid/Mmakefile:
tests/warnings/Mercury.options:
tests/warnings/Mmakefile:
    Enable the new test cases.

tests/invalid/string_format_bad.err_exp:
tests/invalid/string_format_unknown.err_exp:
tests/warnings/disabled_warning.exp:
    Expect the predicate vs function distinction to the printed in
    error messages about bad calls to formatting predicates and functions.
2022-09-24 08:42:36 +10:00
Zoltan Somogyi
30cb4f0ba3 Tighten representation of include/import/use decls.
compiler/prog_item.m:
    Change the representation of include, import and use declarations
    in the data structures of .int0 and .int3 files.

    For both .int0 and .int3 files, switch from data structures that can
    associate one or more contexts with each such declaration with
    data structures that can associate just one. Any duplicates would be
    errors, and we don't want to allow the representation of errors in
    compiler-generated interface files. (Similar updates to .int/.int2
    files are coming soon.)

    For .int3 files, delete two fields that hold information about include
    declarations and import/use declarations respectively in a fully checked
    form. They are not needed, because with invariants that .int3 files
    are subject to (no uses, no implementation section, no implicit imports),
    they contain just the same info as the new data structures mentioned
    in the paragraph above.

compiler/comp_unit_interface.m:
    Update the code that computes the contents of .int0/.int3 files.

    Fix some out-of-sequence variable names.

compiler/convert_parse_tree.m:
    Update the code that converts the generic parsed representation of
    interface files to the specific representations of .int0/.int3 files.

compiler/item_util.m:
    Update the utility predicates that comp_unit_interface.m and
    convert_parse_tree.m use to do their jobs. Add new variants
    of some existing predicates.

compiler/grab_modules.m:
compiler/module_qual.collect_mq_info.m:
compiler/module_qual.qualify_items.m:
compiler/parse_tree_out.m:
compiler/recompilation.check.m:
2022-09-03 11:01:08 +10:00
Zoltan Somogyi
48146680fc Fix formatting of an error message. 2022-08-25 04:39:05 +10:00
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
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
eeb5951a55 Move raw_compilation_unit to convert_parse_tree.m.
compiler/convert_parse_tree.m:
    We used have many operations that worked on the raw_compilation_unit
    representation of the module(s) being compiled, but in the last year,
    we have converted all remaining such algorithms to operate on other
    representations instead. Now, the only thing we use raw_compilation_units
    for is to transfer information from split_parse_tree_src.m to
    convert_parse_tree.m. Therefore move the definition of the
    raw_compilation_unit type, and its raw_item_block component,
    to convert_parse_tree.m. Also, make raw_item_block the only kind
    of item_block; we don't use any other kind of item block anymore.

compiler/prog_item.m:
    Delete the type definitions moved to convert_parse_tree.m.
    Adjust the description of aug_compilation_units accordingly.

compiler/item_util.m:
    Delete unused operations on item blocks.

compiler/prog_item_stats.m:
    Comment out predicates that gathered statistics on item blocks,
    and add "consider_used" pragmas for the predicates that this leaves
    unused. They can be replaced the next time we need statistics
    on item kinds. (For many statistics, e.g. the count of pred_decls,
    the replacement could be as simple as list.length.)
2022-04-04 04:16:41 +10:00
Zoltan Somogyi
7424f93a30 Use one error msg for undeclared mode references.
compiler/add_clause.m:
compiler/make_hlds_passes.m:
    We used to have two separate predicates for generating error messages
    about references to undeclared modes of predicates and functions.
    One, in add_clause.m, was for undeclared modes in mode-specific clauses,
    and generated messages that were as informative as possible.
    The other, in make_hlds_passes.m, which was used for undeclared modes
    in type_spec in foreign_export pragmas, was perfunctory, and gave
    no details.

    Act on an old XXX and delete the second predicate, replacing its uses
    by calls to the first. To make this possible, move the first predicate,
    which used to be private to add_clause.m, to make_hlds_passes.m.

compiler/add_pragma.m:
compiler/add_pragma_type_spec.m:
    Call the first predicate, not the second.

compiler/prog_item.m:
    The first predicate requires access to a varset that describes the names
    of any inst variables in the undeclared mode. Include a varset for this
    purpose in foreign_export pragmas. (type_spec pragmas already had the
    required varset.)

compiler/convert_parse_tree.m:
compiler/get_dependencies.m:
compiler/item_util.m:
compiler/make_hlds_error.m:
compiler/module_qual.qualify_items.m:
compiler/parse_pragma_foreign.m:
compiler/parse_tree_out_pragma.m:
compiler/prog_mutable.m:
    Conform to the change in prog_item.m.

tests/invalid/pragma_qual_error.err_exp:
tests/invalid/type_spec.err_exp:
    Expect updated error messages.
2022-02-23 04:31:38 +11:00
Zoltan Somogyi
ac66a3c788 Carve two new modules out of intermod.m.
compiler/intermod_analysis.m:
compiler/intermod_order_pred_info.m:
    Carve these two new moduiles out of intermod.m.

    intermod_analysis.m contains the parts of the old intermod.m that
    deal with collecting program analysis results in the forms of
    compiler-generated pragmas, and writing them out. These pragmas make up
    the second half of .opt files, and the entirety of .trans_opt files.

    intermod_order_pred_info.m contains some utilities that are needed
    by both intermod_analysis.m and the code that is left in intermod.m.

compiler/intermod.m:
    Remove the code moded to the new modules.

compiler/transform_hlds.m:
    Include the new modules in the transform_hlds package.

compiler/notes/compiler_design.html:
    Describe the new arrangement.

compiler/item_util.m:
    Move a utility function here from intermod.m, since it is (a) now needed
    by intermod_analysis.m as well, and (b) this is its natural home.

compiler/exception_analysis.m:
compiler/mercury_compile_front_end.m:
compiler/mercury_compile_middle_passes.m:
compiler/structure_reuse.analysis.m:
compiler/structure_sharing.analysis.m:
compiler/tabling_analysis.m:
compiler/trailing_analysis.m:
    Conform to the changes above.
2021-12-01 01:42:18 +11:00
Zoltan Somogyi
4126519139 Separate subtypes from du types in parse trees.
compiler/prog_data.m:
    Split type_details_sub from type_details_du, and separate
    parse_tree_sub_type from parse_tree_du_type. This gets us two things:

    - It allows us to encode the prohibition on user-specified equality and
      comparison predicates, and "where direct_arg is" clauses,
      on subtype definitions.

    - It gives us data types we can use to represent (a) only subtype
      definitions, and (b) only non-subtype du definitions.

    Note that this diff deliberately leaves the HLDS representation
    of subtypes unchanged. This is because while a subtype *definition*
    may not specify e.g. equality and comparison predicates, a subtype *can*
    have equality and comparison predicates; it just has to get them from
    its base type. And the same applies to direct args.

compiler/parse_type_defn.m:
    Enforce the invariant that subtypes may not have user-specified equality
    and comparison predicates, or "where direct_arg is" clauses.

    If we find a subtype definition that does have one or both of these
    non-allowed and now-nonrepresentable components, we do still want to
    return the rest of the type definition, in order to avoid misleading
    error messages about that type having no definition at all. To make this
    possible, allow the parsing predicate to return error_specs "alongside",
    as well as "instead of", the item or marker being parsed.

compiler/parse_item.m:
compiler/parse_module.m:
compiler/parse_class.m:
    Handle these "alongside" error messages.

compiler/prog_item.m:
    Separate out subtypes from other du types in type definition maps.

compiler/add_type.m:
    Delete a semantic check that is now in parse_type_defn.m.

    Conform to the change to the representations of subtypes/du types
    in the parse tree.

compiler/item_util.m:
    Add a new utility function for subtypes.

compiler/check_type_inst_mode_defns.m:
compiler/comp_unit_interface.m:
compiler/convert_parse_tree.m:
compiler/decide_type_repn.m:
compiler/equiv_type.m:
compiler/get_dependencies.m:
compiler/intermod.m:
compiler/make_hlds_passes.m:
compiler/make_hlds_separate_items.m:
compiler/module_qual.collect_mq_info.m:
compiler/module_qual.qualify_items.m:
compiler/parse_tree_out.m:
compiler/prog_type.m:
compiler/recompilation.check.m:
compiler/recompilation.version.m:
    Conform to the change to the representations of subtypes/du types
    in the parse tree.
2021-10-02 16:45:26 +10:00
Zoltan Somogyi
12605f8c10 Use checked type/inst/modes in parse_tree_int[123]s.
With this change, we guarantee that if any type, inst or mode
has inconsistent definitions in its defining module, those inconsistencies
will not make it into the the module's .int/.int2/.int3 files, where
they would confuse any compiler invocation that reads them in.

compiler/prog_item.m:
    Replace {type,inst,mode}_ctor_defn_maps, which are unchecked,
    with {type,inst,mode}_ctor_checked_maps in parse_tree_int[123]s.

    To make this possible,

    - generalize the items containing inst and mode definitions the way that
      items containing type definitions have been generalized previously,
      to allow them to store particular *kinds* of inst or mode definitions;

    - move the definitions of type_ctor_checked_map and its components
      here from check_type_inst_mode_defns.m; and

    - add similar, but simpler, definitions for {inst,mode}_ctor_checked_map.

compiler/check_type_inst_mode_defns.m:
    Delete the type definitions moved to prog_item.m.

    Modify the checking process slightly to allow it to check properly
    the definitions we now put into .int, .int2 and .int3 files.

    Add code to check inst and mode definitions as well as type definitions.
    Since insts and modes have only one non-abstract kind of definition,
    these codes are much simpler than the code for checking types.

compiler/comp_unit_interface.m:
    Construct checked type, inst and mode definitions to put into
    .int, .int2 and .int3 files. The .int2 and .int3 parts were
    reasonably simple, but the .int part requires some detailed
    case-by-case analysis.

compiler/convert_parse_tree.m:
    Check the type, inst and mode definitions read in from .int/.int2/.int3
    files when creating their parse trees. If those files were generated
    by a compiler that has this diff, then this checking process should
    not find any problems.

compiler/equiv_type.m:
    Operate on checked type, inst and mode definitions instead of their
    unchecked versions.

    Delete an unneeded field from a structure.

compiler/error_util.m:
    Add {qual,unqual}_{inst,mode}_ctor as format components, so that
    any error messages about inst and mode definitions do not have to convert
    inst_ctors and mode_ctors to symname/arity pairs.

compiler/item_util.m:
    Add some utility predicates and functions needed by the changes above.

compiler/module_qual.collect_mq_info.m:
    Since checked type, inst and mode definitions can contain info that is
    derived from both the interface and implementation sections of a module,
    add the capability to get only the *publicly* declared types, insts and
    modes from their respective kinds of checked definitions.

compiler/module_qual.qualify_items.m:
    Module qualify checked type, inst and mode definitions.

compiler/module_qual.qual_errors.m:
    Treat references to inst_ctors and mode_ctors in qualification error
    messages the same way as we treat type_ctors.

    Also replace mq_ids that are intended to represent classes with class_ids,
    to represent the intent better.

compiler/parse_tree_out.m:
    Output the updated parse_trees of .int/.int2/.int3 files.

compiler/prog_data.m:
    Add an XXX about a future change.

compiler/decide_type_repn.m:
compiler/get_dependencies.m:
compiler/grab_modules.m:
compiler/make_hlds_separate_items.m:
compiler/pred_table.m:
compiler/recompilation.check.m:
compiler/recompilation.version.m:
    Conform to the changes above.

library/maybe.m:
    Add utility predicates needed by the code above.

NEWS:
    Announce the new predicates in maybe.m.

tools/intdiffall:
    A script that shows differences between the automatically generated
    interface files between stage 1 and stage 2, which helped debug this diff.
2021-10-01 17:57:15 +10:00
Zoltan Somogyi
d065635c81 Record source items in type_ctor_checked_defns.
Within each type_ctor_checked_defn, record the original items
(mostly type definition items, and maybe some foreign enum items)
from which that type_ctor_checked_defn was constructed.
This will consist of all the type and foreign enum definition items
recorded for the given type constructor, MINUS the erroneous items
for which the checking process generates error messages.

The intention is to enable a future diff to replace the type_ctor_defn_map
fields in parse_tree_intN with type_ctor_checked_map fields.
Currently, if e.g. module_a.m has inconsistent definitions for a type t,
those definitions get put into module_a.intN. If module_a is imported
by M modules, then these inconsistencies will be reported M times,
once for each import. Generating .intN files from a type_ctor_checked_map
would allow us to report such inconsistencies just when compiling module_a.
It is to make this step possible that we need the consistent (sub)set of the
original items in each type_ctor_checked_defn. (Testing of the changes
in this diff will require the presence of that future diff.)

The simplest way to ensure that we report any of these inconsistencies
the same way when generating target code as when generating interface files
(which is suppressed by default at the moment) would be for a later change
to also replace the lists of item_type_defn_infos and item_foreign_enum_infos
with a type_ctor_checked_map in parse_tree_module_src.

compiler/check_parse_tree_type_defns.m:
    A du type that is a subtype may not have foreign type definitions for it.
    Encode this invariant in the status of such types.

    Generate error messages for foreign type items, as well as foreign enum
    items, for du types that are subtypes.

    Put the definitions of the status types into the same order as the
    corresponding checked type kinds.

    Simplify some code.

compiler/decide_type_repn.m:
    Ignore the extra information in type_ctor_checked_defns.

compiler/convert_parse_tree.m:
compiler/item_util.m:
    Move some utility functions from convert_parse_tree.m to item_util.m,
    to allow check_parse_tree_type_defns.m to use them.
2021-09-08 06:36:42 +10:00
Zoltan Somogyi
163af89c98 Don't put duplicate imports/uses in .int{,0,2}.
The problem addressed by this diff is that copying any duplicate
import_module and/or use_module declarations in .m files to
automatically generated .intN files will cause those errors to be
reported 1+M times, once when compiling the source module, and
once for each of the M modules that import it. Those extra M reports
are not useful; they are only clutter.

compiler/comp_unit_interface.m:
    Do not copy the raw set of import_module and use_module declarations
    from the source file to the .int0 file. Instead, compute them anew
    from the import_and_or_use map, which was built by discarding any
    duplicate declarations, either within a single section, or across
    both sections.

    When deciding which modules to generate a use_module declaration for
    in the implementation section of a .int or .int2 file, do not include
    one for any module which has a use_module declaration in the interface.

compiler/item_util.m:
    Add a predicate that comp_unit_interface.m uses in the first task above.
2021-08-20 20:36:54 +10:00
Zoltan Somogyi
fb1562f41b Fix rcu_ and acu_ field name prefixes. 2021-08-12 08:29:58 +10:00
Zoltan Somogyi
01c5365642 Delete module_and_imports' contains_foreign_* fields.
compiler/module_imports.m:
    As above. The new approach has a much simpler correctness argument,
    especially since some of the methods for initializing module_and_imports
    structures didn't actually fill in one of the fields with meaningful
    information.

    Don't ask callers for arguments that are not used.

compiler/get_dependencies.m:
    Add utility predicates for computing the information that those fields
    used to contain on demand.

    Simplify the interface to some similar recently-added utility predicates.

compiler/make.module_dep_file.m:
    Call those utility predicates when needed.

compiler/item_util.m:
    Delete the utility predicates that module_imports.m *used* to use
    to fill in those fields, which is no longer needed.

compiler/grab_modules.m:
compiler/write_deps_file.m:
    Conform to the changes above.
2021-08-06 13:16:23 +10:00
Zoltan Somogyi
3f5186e6c1 Delete the fims field of module_and_imports.
compiler/module_imports.m:
    Delete the field containing foreign_import_module (fim) info from
    the module_and_imports structure, for two reasons. First, because
    it is redundant; the same info is implicit in the other fields
    of the module_and_imports structure. Second, because its semantics
    were unclear: on different code paths and at different points in time,
    it could contain fims from only the parse_tree_module_src, on other
    code paths it could contain fims from the imported interface and/or
    optimization files as well, and yet on other paths and times
    it could be just set to empty regardless of the presence of fims
    in the module being compiled.

    Replace this with a predicate that calls get_dependencies.m to get fims
    on demand from the parse_tree_module_src.

    Don't give write_deps_file.m info it does not need.

compiler/get_dependencies.m:
    Provide the utility predicate that does that.

compiler/item_util.m:
    Provide helper predicates for the new predicate in get_dependencies.m.
    (Eventually, these could be moved to get_dependencies.m, but while
    the predicate whose logic they follow is in item_util.m, that is
    where they should be.)

compiler/write_deps_file.m:
    Eliminate the special cases in the code that generates the mmake rules
    for dependencies on foreign imported modules. The codes handling the
    two special cases never had any documented or easily discoverable
    correctness arguments, and the fact that we can now never forcibly
    initialize the fims field of the module_and_imports structure to
    the empty list has tickled a bug in at least one of the special cases:
    the fact that it did not restrict the set of fims to be recorded
    to the fims for the relevant target language. Deleting the special
    cases seems a better bet that a bandaid fix on questionable code.

    Also, replace the two rules we used to generate, which were

        modulename.o:     <list of .mh files>
        modulename.pic_o: <list of .mh files>

    where the .mh file lists were always the same with a single mmake rule
    of the form

        modulename.o modulename.pic_o: <list of .mh files>

    In one predicate, do not both updating several fields of a local copy
    of a module_and_imports structure, because the fields that used
    to be update are never read before the variable goes out of scope.

compiler/deps_map.m:
compiler/make.module_dep_file.m:
    Conform to the changes above.
2021-07-31 02:16:54 +10:00
Zoltan Somogyi
d84571c0c2 Delete redundant fields in aug_compilation_units.
compiler/prog_item.m:
    Delete the module name and module name context fields from
    aug_compilation_units, since the same info is available from
    the parse_tree_module_src field.

compiler/comp_unit_interface.m:
compiler/equiv_type.m:
compiler/get_dependencies.m:
compiler/grab_modules.m:
compiler/item_util.m:
compiler/make_hlds_passes.m:
compiler/make_hlds_separate_items.m:
compiler/mercury_compile_main.m:
compiler/module_imports.m:
compiler/module_qual.m:
compiler/prog_item_stats.m:
compiler/write_deps_file.m:
    Conform to the change above.
2021-07-20 06:13:55 +10:00
Zoltan Somogyi
f1927afe0b Break a source file info parse_tree_module_srcs ...
... instead of into raw_compilation_units. Besides being more convenient to
work on, a parse_tree_module_src encodes in its type a significant number
of invariants that a raw_compilation unit does not.

compiler/split_parse_tree_src.m:
    Immediately after creating a raw_compilation_unit for one of the modules
    in a potentially multi-module source file, convert it to a
    parse_tree_module_src.

    Fix an old problem that can come up in contrived erroneous code.
    Specifically, when a submodule is both nested inside its parent module,
    *and* it also has an explicit include_module declaration, we used to
    record the contexts of both "inclusions", after generating an error
    message. The more rigorous checking that later code now does on the
    resulting inclusion map would look at this "duplicate inclusion"
    and generate *another* error message. To avoid this redundant message,
    do not record the contexts of erroneous inclusions for which a message
    has already been generated.

compiler/grab_modules.m:
    Operate on parse_tree_module_srcs instead of raw_compilation_units.
    This allows us to avoid having code for doing what converting the
    raw_compilation_unit to a parse_tree_module_src has already done.
    In fact, that conversion code does a better job. The old code assumed
    that all implicitly available modules are used in the interface,
    whereas in fact only some should be used in the interface, with
    the rest being used in the implementation section.

compiler/module_imports.m:
    Make the predicates that create module_and_imports structures
    take a parse_tree_module_src instead of a raw_compilation_unit
    as input. For now, we convert the parse_tree_module_src back to
    a raw_compilation_unit for further processing, but I intend
    a later diff to change this. Nevertheless, one immediate change
    is that init_module_and_imports now stores the *actual*
    parse_tree_module_src in the module_and_imports structure,
    not a dummy.

compiler/prog_item.m:
    Do not include a list of foreign_enum items in the interface section
    of a parse_tree_module_src, since such items are not allowed to occur
    in interface sections.

    For the same reason, delete the field for foreign_enums in the interface
    sections of .int0 and .int files.

compiler/check_raw_comp_unit.m:
    Operate on parse_tree_module_srcs instead of raw_compilation_units.

compiler/comp_unit_interface.m:
    Operate on parse_tree_module_srcs instead of raw_compilation_units.

    Do not expect any foreign_enum items in interface sections, since
    they are not allowed there.

compiler/read_modules.m:
    Provide a mechanism to remember having read a parse_tree_module_src.

compiler/write_module_interface_files.m:
    Operate on parse_tree_module_srcs instead of raw_compilation_units.

compiler/get_dependencies.m:
    Add a new version of an existing utility predicate. The old one operated
    on raw item lists, the new one operates on parse_tree_module_srcs.
    To make this possible, factor out the code pieces that operate on
    each non-ignored kind of item.

compiler/item_util.m:
    Add some new utility predicates/functions.

compiler/convert_parse_tree.m:
    Conform to the change in prog_item.m. (We already generated an error
    message for a foreign_enum item in the interface, but still passed around
    a list of foreign_enum items that was guaranteed to be stay empty.)

compiler/make.module_dep_file.m:
    Conform to the changes above.

    Use explicit streams in one place.

    Do not pass an unneeded argument.

compiler/check_parse_tree_type_defns.m:
compiler/equiv_type.m:
compiler/make_hlds_separate_items.m:
    Conform to the change in prog_item.m.

compiler/mercury_compile_main.m:
compiler/module_qual.collect_mq_info.m:
compiler/module_qual.qualify_items.m:
compiler/parse_tree_out.m:
    Conform to the changes above.

library/map.m:
library/tree234.m:
    Add foldl6, foldl6_values and foldr6 predicates. An earlier version
    of this diff needed foldl6, and I added the others for symmetry.

NEWS:
    Announce the new library predicates.

tests/invalid/bad_mutable.m:
    Export something, to avoid a warning about not exporting anything.

tests/invalid_submodules/duplicate_module.m:
tests/invalid_submodules/duplicate_module_test.m:
    Update programming style.
2021-07-19 13:23:28 +10:00
Zoltan Somogyi
e2f524d033 Replace some item-block-scanning code.
compiler/module_imports.m:
    There were two data structures, the list of foreign include files
    and the "contains foreign export" flag) that we used to to compute twice:
    once using old code that scanned a list of item blocks, and once using
    more modern data structures. Delete the old-code versions, since
    we haven't had a discrepancy between the two versions for a long time.

    For a third data structure, the set of fims (foreign_import_modules),
    add the new code version, and add code to check for discrepancies.

compiler/item_util.m:
    Delete the old code that used to compute the first two data structures.

compiler/prog_data_foreign.m:
    Add a utility predicate for use by module_imports.m. Give some predicates
    shorter names.

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

compiler/make.dependencies.m:
    Clarify a piece of code.
2021-07-11 20:15:33 +10:00
Zoltan Somogyi
998c1a86af Fix reversed contexts in a diagnostic. 2021-06-23 18:17:12 +10:00
Zoltan Somogyi
7e9d6294bb Stricter checking of tabling pragmas vs grades.
compiler/globals.m:
compiler/table_gen.m:
    Apply stricter checking of whether a tabling pragma conflicts
    with the selected grade. The version in globals.m just says
    whether a tabling pragma is compatible with the selected grade;
    the version in table_gen.m also generates a specific error message
    for each incompatility. (These error messages are not used just yet,
    since the callers of the code in globals.m preempt them.)

compiler/prog_data_pragma.m:
    Separate out tabled eval methods from non-tabled eval methods.
    This enables us to use an eval method type specific to tabling
    (tabled_eval_method) in the several contexts that benefit from one.

compiler/prog_item.m:
    Use the tabled_eval_method type in the representation of tabling
    pragmas.

compiler/llds.m:
    Use the tabled_eval_method type in the tabling_info_struct.

compiler/hlds_pred.m:
    Use the tabled_eval_method type in the proc_table_info_struct.

    Replace functions that operated on eval_methods with functions
    that operate on tabled_eval_methods, when these were the only
    eval_methods (a) they make sense for, or (b) were ever used with.

    Delete a function which would now just duplicate the eval_normal
    vs eval_tabled distinction.

compiler/add_pragma.m:
compiler/add_pragma_tabling.m:
compiler/dead_proc_elim.m:
compiler/det_report.m:
compiler/hlds_out_pred.m:
compiler/item_util.m:
compiler/layout_out.m:
compiler/llds_out_global.m:
compiler/ml_top_gen.m:
compiler/modes.m:
compiler/parse_pragma.m:
compiler/parse_pragma_tabling.m:
compiler/parse_tree_out_pragma.m:
compiler/prog_out.m:
compiler/simplify_goal_call.m:
compiler/tabling_analysis.m:
    Conform to the changes above.

    In several places, fix or improve error messages.
    (Shame that none of them have tests in tests/invalid.)
2021-06-14 14:11:13 +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
8ba45b7892 Compute section infos directly.
compiler/make_hlds_separate_items.m:
    The code that creates lists of items for us to add to the HLDS
    attaches a section info to each item, to tell the code that
    does the adding about the section that the item was found in,
    since that governs several aspects of how the entity defined by the item
    should be treated.

    This code was ancient; it is was updated only minimally during the
    switchover from Fergus's item-lists-everywhere design to my
    use-file-kind-specific-parse-trees design. It was also convoluted;
    the section infos for the two sections (interface and implementation)
    were computed in several stages, whose code was spread over three
    sets of predicates.

    This diff replaces this old code with code that computes those
    section infos directly. The new code is much shorter, and the computation
    of the section infos for e.g. parse_tree_int1 files is all in one place,
    making it much easier to understand.

    Add XXXs for ancient problems that were hid by the old design
    but which the new design makes jump out at the reader.

    Delete predicates used by the old approach that are not needed anymore.
    Any needed parts were effectively inlined into the new code.

compiler/item_util.m:
    Delete the code used by the new approach that is not needed anymore.
    Any needed parts were effectively inlined into the new code.

compiler/prog_item.m:
    Delete types that are no longer needed, some of which haven't been
    needed for a while.

    Delete references to the functions deleted from item_util.m.
    With the new code in make_hlds_separate_items.m, they should not be
    needed.

compiler/prog_item_stats.m:
    Delete commented-out references to types deleted from prog_item.m.

compiler/module_imports.m:
    Delete references in comments to types deleted from prog_item.m.
2021-05-16 14:17:37 +10:00
Zoltan Somogyi
8355718b16 Allow pred pragmas to specify pred_or_func.
Pragmas that apply to a pred_info have traditionally specified that
pred_info by a symname/arity pair. However, this can be ambiguous
if there is both a predicate and a function with that symname/arity pair.
This diff therefore allows pragmas that previously took "symname/arity"
to also take "pred(symname/arity)" and "func(symname/arity").
If e.g. there is both a pred foo/2 and a func foo/2 accessible from
the current module, the old form applied to both, while the new forms
apply to just one.

Later, we could change the behavior of the old form to insist on a
unique match, but before we do, we should have a mechanism that allows
programmers to resolve the ambiguity. (They could rename either the
pred or the func, but it is less intrusive for the compiler not to
insist on that.) This is that mechanism.

In the process of implementing this change, I had to update lots of code
that dealt with arities, since one main difference between predicates
and functions is that for the latter, the user visible arity and
the internal compiler arity are different, in that the former does not
count the return value, and the latter does. The existing "arity" type
is an equivalence to int, and thus does not indicate which notion is meant.
I therefore added two notag types, user_arity and pred_form_arity,
for the two notions above respectively, and made a start on using them,
though for now, only in the code sections affected by the main change above.

compiler/prog_item.m:
    Change the types that represent the specifications of predicates
    (in the sense of pred_infos) and functions to allow the representation
    of not just "symname/arity," but also "pred(symname/arity)" and
    "func(symname/arity"). There is one exception: for the oisu (order
    independent state update) pragma, require the presence of either
    a pred() vs func() wrapper. This is not a breaking change, since oisu
    pragmas are neither publicly documented or really implemented.

    Pragmas that allow the representation of argument modes implicitly
    specify pred vs func by taking the mode list either as
    (m1, m2, ... mn) or as (m1, m2, ...) = mn. Encode this invariant
    in the representation type. Make this type also include an arity
    only in the absence of a mode list, to make unrepresentable
    any inconsistent state in which the stated arity and the length
    of the mode list disagree.

    Give the new types used for these updated representations names
    that state whether they specify a pred_info or a proc_info
    (or in one case that we should later fix, that they can specify either).

    Put the pred or func indication before the symname and arity
    both in these new types, and in some old types. Do this both because
    the pred or func indication comes before the name in Mercury declarations,
    and to help the compiler find all the places where code using the old
    forms had to be revisited and checked for any needed updates.

    Provide utility operations on the new types involved in the
    updated representations.

compiler/prog_data.m:
    Add the user_arity and pred_form_arity types, as mentioned above.

    Add a type that is mostly used in item representations, but is also
    useful elsewhere.

compiler/parse_pragma.m:
compiler/parse_pragma_analysis.m:
compiler/parse_pragma_foreign.m:
compiler/parse_pragma_tabling.m:
compiler/parse_util.m:
    Accept the pred() or func() wrappers mentioned above, and generate
    the updated representations when parsing terms containing pragmas.

compiler/parse_tree_out_pragma.m:
    Accept the updated representations of pragmas when printing them out.

compiler/add_pragma.m:
compiler/add_pragma_tabling.m:
compiler/add_pragma_type_spec.m:
    Use the updated representations when adding pragmas to the HLDS.

compiler/error_util.m:
    Provide mechanisms for use above when printing references to pred_infos
    using user arities, to complement the existing mechanisms which use
    arities that they treat as pred form arities. The latter is what
    you want when generating error messages about pred_infos that
    already included functions' return types in the argument list;
    the former is what you want when generating error messages
    about user input that has not yet been subject to that treatment,
    such as a pragma that has just been read in. (The difference is
    only in what form of arity these mechanisms take as *input*;
    the output is always user arity, which after all is what users
    are interested in.)

compiler/hlds_error_util.m:
    Provide a user_arity equivalent to a piece of existing pred_form_arity
    functionality, for use by the modules above.

    Provide utility functions used when generating error messages.

compiler/fact_table.m:
    Replace most uses of the "arity" type with the "user_arity" type.
    Done mostly in the process of figuring out which kind of arity
    the top predicates took as arguments.

    Put argument lists into a sensible order.

compiler/prog_out.m:
compiler/prog_util.m:
    Add utility functionality needed above.

compiler/add_mutable_aux_preds.m:
compiler/convert_parse_tree.m:
compiler/equiv_type.m:
compiler/get_dependencies.m:
compiler/intermod.m:
compiler/item_util.m:
compiler/make_hlds_passes.m:
compiler/module_qual.qualify_items.m:
compiler/recompilation.usage.m:
compiler/recompilation.version.m:
compiler/typecheck_errors.m:
compiler/unused_args.m:
    Conform to the changes above.

compiler/hlds_pred.m:
    Add an XXX.

compiler/notes/order_indep_state_update:
    Fix typos.

tests/hard_coded/bad_direct_reuse.m:
tests/hard_coded/bad_indirect_reuse.m:
tests/hard_coded/bitmap_simple.m:
tests/hard_coded/constraint_order.m:
tests/hard_coded/equality_pred_which_requires_boxing.m:
tests/hard_coded/fact_table_test_1.m:
tests/hard_coded/float_consistency.m:
tests/hard_coded/foreign_enum_rtti.m:
tests/hard_coded/foreign_enum_switch.m:
tests/hard_coded/foreign_import_module_2.m:
tests/hard_coded/gh72.m:
tests/hard_coded/gh72a.m:
tests/hard_coded/heap_ref_mask_tag.m:
tests/hard_coded/intermod_multimode.m:
tests/hard_coded/mode_check_clauses.m:
tests/hard_coded/multimode_addr.m:
tests/hard_coded/type_spec_ho_term.m:
tests/hard_coded/user_defined_equality2.m:
    Add pred() or func() wrappers to symname/arity pairs in pragmas,
    to test whether the parser accepts them.

    Fix deviations from our current coding standards.

tests/hard_coded/oisu_check_db.m:
tests/invalid/oisu_check_add_pragma_errors.{m,err_exp}:
tests/invalid/oisu_check_semantic_errors.m:
    Add the pred() wrappers now required in oisu pragmas.
    Expect the improved wording of an error message.
2021-05-06 07:19:25 +10:00
Zoltan Somogyi
a19a5f0267 Delete the Erlang backend from the compiler.
compiler/elds.m:
compiler/elds_to_erlang.m:
compiler/erl_backend.m:
compiler/erl_call_gen.m:
compiler/erl_code_gen.m:
compiler/erl_code_util.m:
compiler/erl_rtti.m:
compiler/erl_unify_gen.m:
compiler/erlang_rtti.m:
compiler/mercury_compile_erl_back_end.m:
    Delete these modules, which together constitute the Erlang backend.

compiler/notes/compiler_design.html:
    Delete references to the deleted modules.

compiler/parse_tree_out_type_repn.m:
    Update the format we use to represent the sets of foreign_type and
    foreign_enum declarations for a type as part of its item_type_repn_info,
    now that Erlang is no longer a target language.

compiler/parse_type_repn.m:
    Accept both the updated version of the item_type_repn_info and the
    immediately previous version, since the installed compiler will
    initially generate that previous version. However, stop accepting
    an even older version that we stopped generating several months ago.

compiler/parse_pragma_foreign.m:
    When the compiler finds a reference to Erlang as a foreign language,
    add a message about support for Erlang being discontinued to the error
    message.

    Make the code parsing foreign_decls handle the term containing
    the foreign language the same way as the codes parsing foreign
    codes, procs, types and enums.

    Add a mechanism to help parse_mutable.m to do the same.

compiler/parse_mutable.m:
    When the compiler finds a reference to Erlang as a foreign language,
    print an error message about support for Erlang being discontinued.

compiler/compute_grade.m:
    When the compiler finds a reference to Erlang as a grade component,
    print an informational message about support for Erlang being discontinued.

compiler/pickle.m:
compiler/make.build.m:
    Delete Erlang foreign procs and types.

compiler/add_foreign_enum.m:
compiler/add_mutable_aux_preds.m:
compiler/add_pred.m:
compiler/add_solver.m:
compiler/add_type.m:
compiler/check_libgrades.m:
compiler/check_parse_tree_type_defns.m:
compiler/code_gen.m:
compiler/compile_target_code.m:
compiler/compute_grade.m:
compiler/const_struct.m:
compiler/convert_parse_tree.m:
compiler/dead_proc_elim.m:
compiler/decide_type_repn.m:
compiler/deps_map.m:
compiler/du_type_layout.m:
compiler/export.m:
compiler/foreign.m:
compiler/globals.m:
compiler/granularity.m:
compiler/handle_options.m:
compiler/hlds_code_util.m:
compiler/hlds_data.m:
compiler/hlds_module.m:
compiler/inlining.m:
compiler/int_emu.m:
compiler/intermod.m:
compiler/item_util.m:
compiler/lambda.m:
compiler/lco.m:
compiler/llds_out_file.m:
compiler/make.dependencies.m:
compiler/make.m:
compiler/make.module_dep_file.m:
compiler/make.module_target.m:
compiler/make.program_target.m:
compiler/make.util.m:
compiler/make_hlds_separate_items.m:
compiler/make_hlds_warn.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_code_util.m:
compiler/ml_foreign_proc_gen.m:
compiler/ml_target_util.m:
compiler/ml_top_gen.m:
compiler/mlds.m:
compiler/mlds_dump.m:
compiler/mlds_to_c_export.m:
compiler/mlds_to_c_file.m:
compiler/mlds_to_cs_data.m:
compiler/mlds_to_cs_export.m:
compiler/mlds_to_cs_file.m:
compiler/mlds_to_cs_type.m:
compiler/mlds_to_java_export.m:
compiler/mlds_to_java_file.m:
compiler/mlds_to_java_type.m:
compiler/module_imports.m:
compiler/parse_pragma_foreign.m:
compiler/parse_tree_out.m:
compiler/polymorphism.m:
compiler/pragma_c_gen.m:
compiler/prog_data.m:
compiler/prog_data_foreign.m:
compiler/prog_foreign.m:
compiler/prog_item.m:
compiler/simplify_goal_scope.m:
compiler/special_pred.m:
compiler/string_encoding.m:
compiler/top_level.m:
compiler/uint_emu.m:
compiler/write_deps_file.m:
    Remove references to Erlang as a backend or as a target language.

tests/invalid/bad_foreign_code.{m,err_exp}:
tests/invalid/bad_foreign_decl.{m,err_exp}:
tests/invalid/bad_foreign_enum.{m,err_exp}:
tests/invalid/bad_foreign_export.{m,err_exp}:
tests/invalid/bad_foreign_export_enum.{m,err_exp}:
tests/invalid/bad_foreign_import_module.{m,err_exp}:
tests/invalid/bad_foreign_proc.{m,err_exp}:
tests/invalid/bad_foreign_type.{m,err_exp}:
    Add a test for Erlang as an invalid foreign language. Expect both the
    new error message for this new error, and the updated list of now-valid
    foreign languages on all errors.
2020-10-29 13:24:49 +11:00
Zoltan Somogyi
75b88b03c7 Implement memo attribute disable_warning_if_ignored.
NEWS:
doc/reference_manual.texi:
    Document the new attribute, which, if specified on a pragma memo,
    shuts up the warning that the compiler would otherwise generate
    about that pragma if it had to ignore it because the targeted backend
    does not support memoing.

compiler/prog_data_pragma.m:
    Add the new attributes to the set of tabling attributes.

    Add the new attribute to the eval_memo eval_method as an argument
    in order to preserve it until table_gen.m can act on it. (The other
    tabling attributes are implemented way before that, so the attribute
    structure itself doesn't survive to reach table_gen.m.)

compiler/parse_pragma.m:
    Parse the new pragma, and copy it to the eval method.

compiler/table_gen.m:
    Generate a warning about ignoring a pragma memo only if the new attribute
    does not disable that warning.

compiler/options.m:
    Provide a simple way for the configure script to test whether
    the installed compiler contains this diff.

compiler/hlds_out_module.m:
compiler/hlds_out_pred.m:
compiler/hlds_pred.m:
compiler/item_util.m:
compiler/layout_out.m:
compiler/parse_tree_out_pragma.m:
compiler/prog_out.m:
compiler/tabling_analysis.m:
    Conform to the changes above.
2020-08-19 06:14:58 +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
ab8c2771f7 Move towards generating .opt/.trans_opt files via items.
compiler/prog_item.m:
    Add types for representing .opt and .trans_opt files that specify
    exactly what kinds of items may appear in them.

    Provide a mechanism for representing just the kinds of pragmas
    that we may want to put into .opt files to represent a predicate marker.

    To make the above possible, generalize the item_pragma_info type.

    Do not store the "maybe attributes" field in all pragmas; store it
    in just the one pragma for which it had pragma-specific code (which code
    is dubious anyway). Its only use is to suppress error messages about
    incorrect pragmas if that pragma was created by the compiler, on the
    theory that the user cannot do anything about any such error messages.
    However, if such errors are never reported to anyone, then they won't
    be fixed. I think it is better to allow such problems to be discovered,
    even if they cause a bit of annoyance to the discoverer. The default
    content of the field as set by the parser, item_origin_user, can be
    misleading anway; it is correct when the pragma is read in from a .m file
    or from a .int* file, but it is wrong when read in from a .*opt file,
    since the contents of those are decided by the compiler.

    Store a varset and tvarset in structure sharing and reuse pragmas,
    since without this, one cannot print them out properly.

compiler/intermod.m:
    Change the predicates that write out .opt and .trans_opt files
    to return as large a fraction of the parse trees of those files
    as possible, as a step towards generating those files not directly,
    but by building and then writing out those parse trees. For now,
    we cannot do this fully for .opt files, because for a few item kinds,
    it is far from obvious how to represent as a item what we write out.

    Leave the opening and closing of the file streams for writing out
    .opt and .trans_opt files to our caller, because for .opt files,
    this allows us to avoid having to open the file *twice*.

    Put the output of result-of-analysis pragmas into a standard order.

    Factor out as common code the process for deciding what should go into
    .opt files.

    Give a field of the intermod_info structure a more precise name.

compiler/mercury_compile_front_end.m:
    Hold the stream of the .opt file open between the two different pieces
    of code that write out the two different parts of .opt files.

    If --experiment5 is set, write out the parse tree of the .opt file
    to the .optx file, to enable comparison with the .opt file.

compiler/mercury_compile_middle_passes.m:
    If --experiment5 is set, write out the parse tree of the .trans_opt file
    to the .trans_optx file, to enable comparison with the .trans_opt file.

    Reset a memo table for structure_{sharing,reuse}.analysis.

compiler/structure_reuse.analysis.m:
compiler/structure_sharing.analysis.m:
    Don't take an I/O state pair as arguments, since we needed them *only*
    for that reset, and for progress messages.

    Give the main predicates more descriptive names.

compiler/trailing_analysis.m:
    Give the main predicate a more descriptive names.

compiler/closure_analysis.m:
    Don't take an I/O state pair as arguments, since we needed them *only*
    for progress messages.

compiler/add_pragma.m:
    Don't ignore an error, since one of the other changes in this diff
    could have fixed its cause.

compiler/convert_interface.m:
    Export utility functions needed by code added by this diff.

ompiler/lp_rational.m:
    Tighten the inst of an output argument for use by intermod.m.

    Bring programming style up to date.

compiler/parse_pragma.m:
    Don't put a maybe attributes field into item_pragma_infos.

    Include the varset in structure sharing and reuse pragmas.

    Use simplest_spec where possible.

compiler/parse_tree_out.m:
    Add predicates for writing out the new parse trees of .opt and
    .trans_opt files.

compiler/parse_tree_out_pragma.m:
    Add predicates needed by the new code in parse_tree_out.m.

compiler/add_mutable_aux_preds.m:
compiler/canonicalize_interface.m:
compiler/comp_unit_interface.m:
compiler/equiv_type.m:
compiler/get_dependencies.m:
compiler/grab_modules.m:
compiler/item_util.m:
compiler/make_hlds_error.m:
compiler/make_hlds_passes.m:
compiler/make_hlds_separate_items.m:
compiler/module_qual.qualify_items.m:
compiler/prog_item_stats.m:
compiler/recompilation.version.m:
    Conform to the changes above.
2019-10-30 10:43:39 +11:00
Zoltan Somogyi
d5ade25753 Implement the obsolete_proc pragma.
While the existing obsolete pragma declares an entire predicate or function
obsolete, the new obsolete_proc pragma does this for only THE NAMED MODE
of a predicate or function.

NEWS:
doc/reference_manual.texi:
    Mention and document the new pragma.

compiler/prog_item.m:
    Add the new pragma. Rename the old pragma to "obsolete_pred". (This affects
    only the compiler's internal name; the user visible name stays the same.)

    Move a type definition next to its related types.

compiler/parse_pragma.m:
    Read in the new pragma.

compiler/hlds_pred.m:
    Create a slot in proc_infos for the information in the new pragma.

compiler/add_pragma.m:
    Add the new pragma to the HLDS.

    To avoid adding to the substantial existing code duplication in this
    module, factor out two commonly recurring pieces of code: one that
    looks up the (hopefully unique) pred_id specified by a pragma, and
    one that looks up and (if found) transforms the procedure specified
    by a pragma.

    Use error-message phraseology consistent with that employed by
    the newly-factored-out predicate even in places that cannot use them.

    Move the code handling foreign_export pragma here from add_foreign_proc.m
    to take advantage of the newly-factored out predicates.

compiler/add_foreign_proc.m:
    Delete the code moved to add_pragma.m.

    Fix the structure of the remaining code by putting related code fragments
    next to each other.

compiler/simplify_goal_call.m:
    Generate warnings to obsolete procedures as well as obsolete predicates.

compiler/parse_tree_out_pragma.m:
    Output the new pragma.

    Factor out existing common code.

compiler/hlds_code_util.m:
    Put a predicate's arguments into a more meaningful order.

compiler/make_hlds_error.m:
    Allow the caller of report_undefined_pred_or_func_error to specify
    whether the error applies to a predicate or a function. Most callers
    don't have that info, but some do, and using this info when available
    allows us to generate a more specific error message.

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

    Make a predicate easier to read by moving unimportant code out-of-line.

compiler/intermod.m:
    Conform to the changes above. Do this in a way that is adaptable to
    making intermod.m generate lists of items instead of simply writing
    stuff out, even though this makes the diff to this file more complex
    than immediately necessary.

compiler/add_mutable_aux_preds.m:
compiler/add_pragma_type_spec.m:
compiler/canonicalize_interface.m:
compiler/equiv_type.m:
compiler/get_dependencies.m:
compiler/item_util.m:
compiler/make_hlds_passes.m:
compiler/make_hlds_separate_items.m:
compiler/module_qual.qualify_items.m:
compiler/prog_data_pragma.m:
compiler/prog_item_stats.m:
compiler/recompilation.version.m:
    Conform to the changes above.

compiler/options.m:
    Provide a simple way for the configure script to test for the presence
    of this new addition.

tests/invalid/obsolete_proc_pragma.{m,err_exp}:
    A test case for the new pragma.

tests/invalid/Mmakefile:
tests/invalid/Mercury.options:
    Enable the new test case, and set it to run with --halt-at-warn.

tests/invalid/bug83.err_exp:
tests/invalid/require_tailrec_invalid.err_exp:
    Update these two files to expect updated error messages.
2019-10-23 05:04:41 +11:00
Zoltan Somogyi
8e62f93c4d Use maps for several kinds of items in interface file parse trees.
Using lists to store type-, inst- and mode definitions, foreign enum
definitions and type representation items does nothing to enforce
uniqueness requirements, such as "every inst constructor should have
at most one one non-abstract definition in the interface of a module".
However, one can encode such requirements using maps.

This diff therefore changes the representation of these kinds of items
inside the interface-kind-specific parse trees of interface files to use
these kinds of maps. It does not take advantage of the possilities
offered by this diff; that is for a later change.

compiler/prog_item.m:
    Make the change described above.

    Since after this diff, the info in foreign_enum pragmas will be in a map,
    while the info in other kinds of pragmas will still be in a list, avoid
    the possibility of being able to represent invalid states by giving
    foreign enums their own item kind, separate from that of pragmas.
    Since foreign export enums are handled very similarly to foreign enum
    pragmas in many places, given them their own item kind as well.

    Update the predicates converting generic interface file parse trees
    to interface-kind-specific parse trees, and vice versa, to conform
    to the changes above.

compiler/comp_unit_interface.m:
    Convert lists to maps before putting them into interface-kind-specific
    parse trees where the above change requires it.

compiler/hlds_module.m:
    Delete types that contain almost exactly the same info as the item
    information we now keep for foreign enum and foreign export enum items.

    Include the item status next to foreign enum items, since that is the
    one piece of info the deleted types had that we need.

compiler/parse_pragma.m:
compiler/parse_tree_out.m:
compiler/parse_tree_out_pragma.m:
    Parse and print out foreign enums and foreign export enums as their
    own item kinds, not as kinds of pragmas.

compiler/add_foreign_enum.m:
compiler/canonicalize_interface.m:
compiler/equiv_type.m:
compiler/get_dependencies.m:
compiler/grab_modules.m:
compiler/intermod.m:
compiler/item_util.m:
compiler/make_hlds.m:
compiler/make_hlds_separate_items.m:
compiler/module_qual.collect_mq_info.m:
compiler/module_qual.qual_errors.m:
compiler/module_qual.qualify_items.m:
compiler/prog_item_stats.m:
compiler/recompilation.check.m:
compiler/recompilation.version.m:
    Conform to the changes above.
2019-09-12 03:52:10 +10:00
Zoltan Somogyi
0584bc300d Expand obsolete pragmas with an optional "suggested replacements" field.
doc/reference_manual.texi:
NEWS:
    Document the extension.

compiler/prog_item.m:
    Add a field to the representation of obsolete pragmas to hold
    an optional list of suggested possible replacements.

compiler/parse_pragma.m:
    Parse the optional second argument in obsolete pragmas.

    Improve the error messages we generate for several kinds of errors
    we may encounter when parsing pragmas by making them more specific.

compiler/hlds_pred.m:
    Since an obsolete pragma now contains more than one bit of information
    (present vs not present), change their representation from a simple marker
    to a field containing the possible replacements.

    Make a comment about access stats more useful by sorting its contents
    on frequency of access, and putting it before the structure it is about.

compiler/simplify_goal_call.m:
    When generating warnings about calls to obsolete predicates or functions,
    mention the suggested replacements, if there are any.

compiler/add_pragma.m:
    Fill in the new field when adding an obsolete pragma to the HLDS.

compiler/globals.m:
    Add a function for use by new codee in parse_pragma.m.

compiler/canonicalize_interface.m:
compiler/equiv_type.m:
compiler/get_dependencies.m:
compiler/hlds_out_pred.m:
compiler/intermod.m:
compiler/item_util.m:
compiler/make_hlds_separate_items.m:
compiler/module_qual.qualify_items.m:
compiler/parse_tree_out_pragma.m:
compiler/prog_item_stats.m:
compiler/recompilation.version.m:
compiler/table_gen.m:
    Conform to the changes above.

tests/invalid/bad_foreign_code.err_exp:
tests/invalid/bad_foreign_enum.err_exp:
tests/invalid/bad_foreign_export.err_exp:
    Expect the improved error messages from parse_pragma.m.

tests/warnings/simple_code.{m,exp}:
    Add tests of the new forms of the obsolete pragma.
2019-09-09 13:53:21 +10:00
Zoltan Somogyi
615d2795c8 Take foreign_import_modules out of the item type.
compiler/prog_item.m:
    Even though we express foreign import module declarations syntactically
    as pragmas, semantically, they are much closer to import_module
    declarations. This means that the treatment they require in most places
    in the compiler is similar to the treatment of import_module declarations,
    and quite different from the treatment of other kinds of items.
    Therefore this diff takes foreign_import_module declarations (FIMs
    for short) out of item type. From now on, in parse trees and their
    components, FIMs are stored in data structures of their own, next to
    import_module declarations.

compiler/parse_types.m:
    Provide a mechanism for the parser to return FIMs as an entity kind
    of its own, not as an item.

compiler/comp_unit_interface.m:
    Conform to the changes above, and give a predicate a more specific name.

compiler/module_qual.m:
    Conform to the changes above, and require .int3 files to contain no FIMs.

compiler/canonicalize_interface.m:
compiler/check_raw_comp_unit.m:
compiler/equiv_type.m:
compiler/get_dependencies.m:
compiler/grab_modules.m:
compiler/hlds_module.m:
compiler/item_util.m:
compiler/make_hlds_passes.m:
compiler/make_hlds_separate_items.m:
compiler/module_imports.m:
compiler/module_qual.collect_mq_info.m:
compiler/module_qual.qualify_items.m:
compiler/parse_module.m:
compiler/parse_pragma.m:
compiler/parse_tree_out.m:
compiler/prog_item_stats.m:
compiler/read_modules.m:
compiler/recompilation.check.m:
compiler/recompilation.version.m:
compiler/split_parse_tree_src.m:
    Conform to the changes above.
2019-08-22 09:31:10 +10:00
Zoltan Somogyi
43ebb15bbc Move a predicate to where it is used.
compiler/comp_unit_interface.m:
    Move a predicate here from item_util.m, since it is used only here.

    Inline a one-line predicate from item_util.m.

compiler/item_util.m:
    Delete the moved predicate, the inlined predicate (since it has no calls
    left to it), and a third predicate that has been dead for a while.
2019-07-11 13:57:26 +02:00
Zoltan Somogyi
de0a5f13b7 Delete item_nothing.
compiler/prog_item.m:
    Delete item_nothing as an alternative in the item type.

    These items never occur in parse trees, being handled fully at the time
    when the parse tree is constructed. Nevertheless, their presence in
    the item type required code that handles parse trees to worry NOW about
    how they should handle item_nothings in case a possible future change
    let them survive the parse tree construction process.

compiler/parse_types.m:
    Replace item_nothing with iom_handled in the item_or_marker type,
    whose values are used only during the parse tree construction process.

    The replacement is significantly simplified compared with the original,
    containing only the functionality that our current use cases need.

compiler/parse_error.m:
    Remove rme_warn_item_nothing from the read_module_error type.
    It was being added to error sets, but nothing ever tested for its presence.
    Its task as a signifier of the presence of a compilation-stopping error
    now belongs to the severity of the associated error_specs.

compiler/parse_item.m:
    Fix the logic of the code that decides whether the format of the
    version_numbers_map item is recorded in an obsolete format
    (i.e. whether its *own* version is too old). Specificially,
    treat non-numerical "version number" terms as being malformed,
    not as being obsolete.

compiler/canonicalize_interface.m:
compiler/check_raw_comp_unit.m:
compiler/comp_unit_interface.m:
compiler/equiv_type.m:
compiler/get_dependencies.m:
compiler/item_util.m:
compiler/make_hlds_separate_items.m:
compiler/module_qual.collect_mq_info.m:
compiler/module_qual.qualify_items.m:
compiler/modules.m:
compiler/parse_module.m:
compiler/parse_pragma.m:
compiler/parse_tree_out.m:
compiler/prog_item_stats.m:
compiler/recompilation.check.m:
compiler/recompilation.version.m:
    Conform to the changes above.
2019-04-15 03:30:15 +10:00
Zoltan Somogyi
d49f6eab84 Add missing imports of parent modules.
These imports were missing from source files, but were included in imported
modules' .int3 files. An upcoming change will delete these from those .int3
files.
2019-03-20 03:57:10 +11:00
Zoltan Somogyi
d1f4872ed5 Construct .int files much more directly.
The predicates in write_module_interface_files.m that construct .int files
have traditionally done so in a fairly convoluted manner. This diff adds
a way to construct them much more directly.

compiler/comp_unit_interface.m:
    Add this direct code to construct .int files. Some of the predicates
    involved are modified copies, sort-of duplicates, of the originals
    in write_module_interface_files.m, but they have been rewritten
    to process each item the minimum number of times. This is mainly
    to improve code clarity, though it should help performance as well.
    Also improve clarity by providing much more thorough comments,
    both on the current totally-backwards-compatible behavior of the code,
    and on possible future improvements.

compiler/write_module_interface_files.m:
    Generate the contents we want to put into .int files *both*
    using the new code in comp_unit_interface.m and the old code.
    As a temporary sanity check, check that their outputs agree.
    (In the absence of any problems, we should delete the old code
    in a week or two; this will do undo the sort-of duplication
    mentioned above.)

compiler/item_util.m:
    Throw an exception if we find type_repn items, since we do not
    generate them yet. This will make it easier to find the places
    that need to be updated when we *do* start generating them.

compiler/module_imports.m:
    Add a comment.

compiler/prog_item.m:
    Change the prefix on the field names in a type to avoid an ambiguity.
2019-02-15 17:12:56 +11:00
Zoltan Somogyi
df50e1ff80 Construct .int3 files much more directly.
The predicates in write_module_interface_files.m that construct
the various kinds of interface files (.int0, .int, .int2 and .int3)
have traditionally done so in a fairly convoluted manner.

- They perform multiple passes over the item lists in the compilation unit.
  Since each item is processed many times, there is no one place that
  one can look in to see whether, and if yes in what form, items of a
  particular kind end up in the final output. This makes it effectively
  impossible to come up with a simple description of what each kind of
  interface file is supposed to contain.

  It is also unnecessarily slow, though that is a far smaller problem
  than the lack of clarity.

- The codes of several of these passes are used to construct more than one
  kind of interface file. This means that a change to the code of a pass
  to fix a problem with one kind of interface file (e.g. it may have been
  missing some information) can cause a problem with another kind of
  interface file (e.g. after the pass is "fixed", this other kind of
  interface file may now contain *too much* information). Some parts
  of these passes are parameterised to avoid this problem, but I am pretty
  sure that instances of it remain. And avoiding adding other instances
  in the future though this unwanted coupling is an unnecessary burden
  on future maintainers.

This diff takes the first step in fixing this situation by adding
bespoke code to generate the contents of .int3 files.

compiler/comp_unit_interface.m:
    Add this bespoke code. This code does just one pass over the raw
    compilation unit of the module, so the fate of each kind of item
    is visible in one place.

    The new bespoke code preserves the behavior of the old code exactly,
    except for fixing one old bug.

    Add XXXs where I think the old behavior could be improved.

compiler/write_module_interface_files.m:
    Call the new bespoke code in comp_unit_interface.m to construct
    .int3 files, instead of using the old multi-pass method.

    Delete some predicates that the changes above have made dead code.

    Delete a utility predicate that was moved to comp_unit_interface.m,
    since the bespoke code needed it.

    When a predicate used to help construct both .int2 and .int3 files,
    but now is used only to create .int2 files, specialize it for that use.

compiler/item_util.m:
    Carve out the part of an existing predicate handling items
    that handles pragmas, and export it to comp_unit_interface.m
    as a separate predicate.

    When a predicate used to help construct both .int2 and .int3 files,
    but now is used only to create .int2 files, specialize it for that use.
2019-01-31 15:10:01 +11:00
Zoltan Somogyi
009607f6e4 Fix typos. 2019-01-29 13:38:19 +11:00
Zoltan Somogyi
5cf4d9608f Make foreign_import_module a separate kind of item.
compiler/prog_item.m:
    Change foreign_import_module from being a kind of pragma item, to being
    an item in its own right. Although we use pragma syntax to represent them,
    they are NOT allowed in source files. (Though we do not yet enforce this.)

compiler/add_pragma.m:
compiler/comp_unit_interface.m:
compiler/equiv_type.m:
compiler/get_dependencies.m
compiler/hlds_module.m::
compiler/intermod.m:
compiler/make_hlds_passes.m:
compiler/make_hlds_separate_items.m:
compiler/module_qual.collect_mq_info.m:
compiler/module_qual.qualify_items.m:
compiler/modules.m:
compiler/parse_tree_out.m:
compiler/parse_tree_out_pragma.m:
compiler/prog_item_stats.m:
compiler/recompilation.check.m:
compiler/recompilation.version.m:
compiler/write_module_interface_files.m:
    Conform to the change above by treating the item kind as the pragma kind
    it replaced.

compiler/parse_pragma.m:
    As above, but also improve variable names.

compiler/item_util.m:
    Conform to the change above, but treat the item kind differently from
    the pragma kind it replaced, by not stating that foreign_import_module items
    require the presence of *other* module imports. (They don't.)
2019-01-29 02:58:01 +11:00
Zoltan Somogyi
8375518c9e Avoid storing some redundant info.
compiler/write_module_interface_files.m:
    The type map used to map a type_ctor to a pair: the prog_item that
    defined it, and the type definition extracted from this item.

    Storing both made sense when we had no purpose-specific types
    for each particular kind of prog_item. Now that we do, storing both
    is unnecessary, so stop doing it.

    Document some possible problems.

compiler/item_util.m:
    Note a link between a predicate in write_module_interface_files.m
    and a predicate in this module.
2019-01-27 00:35:55 +11:00
Zoltan Somogyi
fb97df69ed Make "compute type representations" a separate pass.
The ultimate purpose of this diff is to prepare for future improvements
in type representations, allowing values of some data types to be represented
more compactly than up to now.

The main way this diff does that is by creating a separate pass for deciding
how values of each type should be represented. We have traditionally decided
data representations for each type as its type definition was processed
during the make_hlds pass, but these decisions were always tentative,
and could be overridden later, e.g. when we processed foreign_type or
foreign_enum pragmas for the type. This dispersed decision making algorithm
is hard to understand, and therefore to change.

This diff centralizes decisions about type representations in a separate
pass that does nothing else. It leaves the algorithm distributed among
several files (du_type_layout.m, make_tags.m, and add_foreign_enum.m) for now,
to make reviewing this diff easier, but soon after it is committed I intend
to move all the relevant code to du_type_layout.m, to centralize the decision
code in "space" as well as in time.

For the reason why this pass runs before any of the semantic analysis
passes, instead of after all of them as I originally intended and as we
discussed on m-dev in late october 2017, see the big comment at the start of
du_type_layout.m.

As per another part of that same discussion on m-dev, this diff
makes a start on implementing a new type of item, the type_repn item,
which is intended *only* to be used in compiler-generated interface files,
*not* in source files. It is only a start because we can use these items
only *after* the creation of a separate type representation decision pass,
and this diff is already very big. The code for making the compiler understand
these items will be added later. The code for generating them will be added
later still, once the code for understanding them has been installed on
all our systems.

Since I was going to be working on the affected code anyway, this diff
also carries out two other decisions that came out of that discussion:

- the deletion of the ability to reserve a tag in a type for HAL,
  either via a compiler option or via a pragma, and

- the deletion of the ability to represent a functor using the address
  of a statically allocated object (which we haven't used and won't use,
  because it slows down accesses to *all the other functors* of the type).

compiler/mercury_compile_front_end.m:
    Invoke the new pass for making decisions about type representations
    after the make_hlds pass. (We used to do only the final part of it then.)

    Fix a bad dump stage name.

    Add an extra check for what it means for a module to be error free.

    Make a sub-switch explicit.

compiler/hlds.m:
compiler/make_hlds.m:
    Move the modules that implement the new pass from the make_hlds package
    to the hlds package, to give the compiler's top level access to them.

    Make the same move for the modules that the new pass's modules need.
    Since they are now part of hlds, they cannot reach into make_hlds,
    and I think this is a cleaner solution than forwarding predicates.

    Delete some forwarding predicates that are no longer needed.

compiler/notes/compiler_design.html:
    Document the updated location of the moved modules.

    Add an XXX to note a place where the documentation has not been
    updated in the past.

compiler/du_type_layout.m:
    Add code to implement the new pass.

    Keep the algorithm for deciding type representations as close
    to the previously used algorithm as possible, since this diff
    is already big enough. (The previous algorithm was scattered across
    add_type.m, add_foreign_enum.m, and make_hlds_passes.m.)

    Simplifications and optimizations will come later, after this module
    is merged with make_tags.m and with (at least) the foreign_enum half of
    add_foreign_enum.m.

compiler/make_tags.m:
    Keep the functionality of this module, which does both the first part
    of deciding type representations (tentatively assigning tags to functors,
    an assignment that may be overridden later), and the last part (packing
    multiple adjacent less-than-word-sized enum args into a single word,
    if possible.), but simplify it where possible, and note possibilities
    for further improvements.

compiler/add_foreign_enum.m:
    This module has two halves, one dealing with foreign_enum pragmas
    and one dealing with foreign_export_enum pragmas.

    Change the half that deals with foreign_enum pragmas to just build
    a data structure that du_type_layout.m will need to make its decisions,
    this structure being a map from type_ctors to the foreign enum
    specification applicable to the current target language. Include
    in this structure a component that add_foreign_enum.m itself can use
    to report better error messages for duplicate foreign_enum pragmas;
    this component records, for each type_ctor and language, the context
    of the previous foreign_enum pragma for that combo.

    Change the input for the half that deals with foreign_export_enum pragmas
    to reflect the fact that it is invoked by du_type_layout.m after all
    decisions about type representations have already been made.

compiler/add_special_pred.m:
    Move this module from the make_hlds package to the hlds package,
    since the code that adds special preds for type is now called from
    du_type_layout.m.

    Change the names of predicates to make clear whether they add
    only the declaration of a predicate, only its definition, or both.

    Don't try to pre-guess whether the implementation of a type's
    compare predicate will need an index predicate. Let the code
    that generates calls to the index predicate both declare and define
    the index predicate. This change removes the potential for
    inconsistencies between the two pieces of code.

compiler/add_pred.m:
    Move this module from the make_hlds package to the hlds package,
    since add_special_pred.m needs access to it.

compiler/add_type.m:
    When adding a type definition to the HLDS, don't try to decide
    its representation. Any such decision was tentative anyway, due
    to the possibility of e.g. the later processing of foreign_type
    or foreign_enum pragmas for the type. Likewise, don't try to
    create the special (unify, compare) predicates for the type.
    Leave both tasks to the du_type_layout pass.

    Likewise, don't try to pack the representation of types, or record
    no_tag types in the table of no_tag types, during the post-processing
    pass either; leave both of these to du_type_layout as well.
    Rename the predicate that post_processes type definitions to reflect
    the two tasks left for it to do.

compiler/prog_data.m:
    Do not store width information about the arguments of those data
    constructors in the parse tree. That information is not computed
    until later; until then, it was always filled in with dummy values.
    (But see hlds_data.m below.)

    Use bespoke types to represent the presence or absence of user-specified
    unify and compare predicates.

    Change the representation of data constructors to use a single "maybe"
    type, not two lists, to denote the presence or absence of existentially
    typed arguments.

    Give the HLDS the ability to hold representation information about
    abstract types that in the future we will get from type_repn items
    in the defining modules' interface files.

    Delete the uses_reserved_tag type, since we never use reserved tags
    anymore.

compiler/prog_item.m:
    Add the new type_repn item type, which is not used yet.

    Delete the reserve_tag pragma.

    Fix an earlier mistake in the wording of a context message.

compiler/hlds_data.m:
    Put all the fields of hlds_du_type (the type definition variant dealing
    with discriminated union types) that deal with type representation
    issues in a single "maybe" field that is set to "no" before the
    type representation decision pass has been run.

    Add new type, constructor_repn, that stores the same information as the old
    constructor type (defined in prog_data.m), PLUS the information
    describing how terms with that data constructor are stored.

    Likewise, add a new type ctor_arg_rep, which likewise stores
    the widths of each constructor argument. When we implement
    argument reordering, we would store the offset of the arg as well.

    Since the parse tree representations of constructors and their arguments
    don't store representation information anymore, the cons_table they
    are stored in doesn't either. Make the lookup of representation information
    for a given constructor possible by adding a map to the new "maybe" field
    of hlds_du_type.

    Provide some utility predicates.

    Optimize some existing predicates.

    Rename some types to better reflect their meaning.

compiler/hlds_module.m:
    Provide a slot in the module_info for storing the information
    gathered by make_hlds.m that is needed by the new pass.

compiler/make_hlds_separate_items.m:
    When we see either a foreign_enum or a foreign_export_enum pragma,
    return values of a bespoke type for them (a type defined in
    hlds_module.m), instead of an item_pragma. This makes handling them
    considerably easier.

compiler/make_hlds_passes.m:
    With the changes in this diff, adding a type to the HLDS won't
    decide its representation. Therefore delete the code that used
    to loop over foreign_export_enum pragmas; in the absence of
    the final type representation information, it won't work right.

    Record the information that the du_type_layout pass will need
    in the module_info.

compiler/add_pragma.m:
    Delete the code for passing on foreign_enum and foreign_export_enum
    pragmas to add_foreign_enum.m; they are now passed to add_foreign_enum.m
    by du_type_layout.m.

    Move a utility predicate to make_hlds_error.m, to allow add_foreign_enum.m
    to call it.

compiler/make_hlds_error.m:
    Add the utility predicate moved from add_pragma.m.

    Move the module from the make_hlds to the hlds package.

compiler/module_qual.m:
    Provide a mechanism for recording error messages about e.g. undefined
    types without recording that we found an undefined type. This sounds
    strange, but there is a valid use case.

    When a type definition declares a functor's argument to be of an
    undefined type, that error is usually fatal; we stop the compiler
    from proceeding even to typechecking, since the typechecker will
    probably abort with a map lookup failure. Most other references
    to undefined types are similarly fatal for the same reason. However,
    if e.g. a foreign_export_enum pragma refers to an undefined type,
    that error *won't* be visible to the typechecker, and therefore
    won't crash it. The error will still cause the compiler to exit
    without generating any target language code, but at least it will be
    able to run the typechecker and other semantic analysis passes.

    Without this change, the compiler will report only one error in
    the ee_invalid.m test case; with it, it reports *every* error
    in the test case expected output.

compiler/module_qual.qualify_items.m:
    Use the capability describe above for undefined types in
    foreign_export_enum pragmas.

compiler/module_qual.qual_errors.m:
    Delete a (somewhat incorrect) copy of a predicate in prog_item.m,
    to reduce code duplication.

compiler/prog_type.m:
    Add ways to represent abstract types whose representations are nevertheless
    known (from type_repn items in the defining modules' interface files)
    to be notag or dummy types. This will be needed to fix Mantis bug #441,
    a fix that will probably be one of the first later changes to build
    on this diff.

    Delete a type moved to type_util.m.

compiler/type_util.m:
    Provide extra versions of some predicates, with the difference between
    the old and the new versions being that one requires type representations
    to have been decided already, and the other one does not.

    Move the definition of the ctor_defn type here from prog_type.m,
    since prog_type.m itself does not use it, but type_util.m does.

    Give some predicates more meaningful names.

compiler/parse_type_defn.m:
    Simplify the code for parsing type definitions, to make it easier
    to reuse to parse type_repn items.

    Add a sanity check that requires existential constraints to have
    *some* existential variables to apply to.

    Allow "type_is_representable_in_n_bits" as a synonym for
    "type_is_abstract_enum", since in the future we want to be able to pack
    e.g. multiple int8s, not just multiple enums, into a single word.

    Generate more specific error messages for some classes of malformed input.

compiler/parse_type_repn.m:
    New module to parse type_repn items.

compiler/polymorphism.m:
    Make some predicates that operate on type constructors take
    the type constructors themselves as input arguments, not a whole type
    *using* that type constructor. Put the arguments of those predicates
    in a more standard order.

    Note that some predicates don't belong in this module.

compiler/special_pred.m:
    Make the code that decides whether a special predicate for a type
    constructor can be defined lazily avoid using type representation
    information. (Actually, we now make decisions about lazy vs eager
    definitions after type representation is available, but that was
    not so in an earlier version of this change, and the new code
    is more robust.)

compiler/unify_proc.m:
    When we decide to generate code for a compare predicate that needs
    the type to have an index predicate, don't presume that the index
    predicate has already been declared and defined; instead, declare
    and define it then and there. (Index predicates are *never* called
    from anywhere else.)

    Pack the information needed to define a special predicate
    into a single structure, to simplify the above.

    Since the creation of a clause for a compare predicate may now require
    the declaration and definition of an index predicate, the module_info
    field of the unify_proc_info is now a writeable field.

    Give some predicates and function symbols more meaningful names.

    Note some problems with the existing code.

compiler/add_class.m:
compiler/add_clause.m:
compiler/add_foreign_proc.m:
compiler/add_mode.m:
compiler/add_mutable_aux_preds.m:
compiler/add_pragma_tabling.m:
compiler/add_pragma_type_spec.m:
compiler/add_solver.m:
compiler/check_typeclass.m:
compiler/code_info.m:
compiler/comp_unit_interface.m:
compiler/ctgc.selector.m:
compiler/ctgc.util.m:
compiler/default_func_mode.m:
compiler/det_report.m:
compiler/equiv_type.m:
compiler/equiv_type_hlds.m:
compiler/erl_code_gen.m:
compiler/export.m:
compiler/foreign.m:
compiler/get_dependencies.m:
compiler/goal_expr_to_goal.m:
compiler/hhf.m:
compiler/higher_order.m:
compiler/hlds_code_util.m:
compiler/hlds_out_module.m:
compiler/inst_check.m:
compiler/inst_test.m:
compiler/inst_util.m:
compiler/intermod.m:
compiler/item_util.m:
compiler/make_hlds_warn.m:
compiler/ml_accurate_gc.m:
compiler/ml_simplify_switch.m:
compiler/ml_type_gen.m:
compiler/ml_unify_gen.m:
compiler/mlds_to_cs.m:
compiler/mlds_to_java.m:
compiler/mode_util.m:
compiler/modecheck_goal.m:
compiler/module_qual.collect_mq_info.m:
compiler/modules.m:
compiler/parse_item.m:
compiler/parse_pragma.m:
compiler/parse_tree.m:
compiler/parse_tree_out.m:
compiler/parse_tree_out_pragma.m:
compiler/post_term_analysis.m:
compiler/proc_requests.m:
compiler/prog_item_stats.m:
compiler/qual_info.m:
compiler/recompilation.check.m:
compiler/recompilation.usage.m:
compiler/recompilation.version.m:
compiler/resolve_unify_functor.m:
compiler/rtti.m:
compiler/rtti_out.m:
compiler/rtti_to_mlds.m:
compiler/simplify_goal_ite.m:
compiler/stack_opt.m:
compiler/state_var.m:
compiler/structure_reuse.direct.choose_reuse.m:
compiler/superhomogeneous.m:
compiler/switch_gen.m:
compiler/switch_util.m:
compiler/table_gen.m:
compiler/term_constr_build.m:
compiler/term_norm.m:
compiler/trailing_analysis.m:
compiler/type_constraints.m:
compiler/type_ctor_info.m:
compiler/typecheck.m:
compiler/unify_gen.m:
compiler/untupling.m:
compiler/unused_imports.m:
compiler/write_module_interface_files.m:
compiler/xml_documentation.m:
    Conform to the changes above.

tests/invalid/Mmakefile:
    Disable the reserve_tag test case, as it is not applicable anymore.

tests/invalid/exported_foreign_enum.{m,err_exp}:
tests/invalid/pragma_qual_error.{m,err_exp}:
    Delete reserve_tag pragmas from these test cases, and its effects
    from the expected outputs.

tests/invalid/bad_foreign_type.err_exp:
tests/invalid/bigtest.err_exp:
tests/invalid/foreign_enum_invalid.err_exp:
tests/invalid/type_lhs_var.err_exp:
tests/invalid/uu_type.err_exp:
tests/invalid/where_abstract_enum.err_exp:
tests/invalid/where_direct_arg.err_exp:
    Expect the updated messages for some errors.

tests/valid/Mmake.valid.common:
tests/valid/Mmakefile:
    Disable any reserve_tag test cases, as they are not applicable anymore.
2018-01-31 17:54:40 +11:00
Zoltan Somogyi
2ac8465659 Make the code adding new types to the HLDS readable.
The motivation for this diff was that I wanted the compiler to generate
a warning if a module declared the same type twice. (During the cleanup
of unify_proc.m I did recently, I found and fixed such a duplicate
declaration.)

compiler/add_type.m:
    The old code of module_add_type_defn was not just long (210+ lines),
    it is also very complex.

    Part of this complexity was sort-of justified. It dealt with adding
    three separate kinds of item_type_defns: abstract type "definitions",
    which are actually declarations; the definitions of Mercury types,
    and the definitions of foreign types. A single type could have more than
    one of these (e.g. declaration and a definition, or a Mercury definition
    and a foreign definition), and it had to be prepared to process these
    in any order.

    Part of this complexity was self-inflicted. The parts of the predicate
    that dealt with the same kind of definition were not always next to each
    other, and for some parts, it wasn't even clear *what* kind of definition
    it was dealing with. It did the same tests on both the old and updated
    versions of definitions, when those definitions were guaranteed to be
    identical; the "updating" predicate was a no-op. And it used completely
    different code for detecting and handling related errors.

    This diff fixes the above problems. It separates the task of adding
    an item_type_defn to the HLDS into three subtasks, done in three separate
    predicates: adding type declarations, adding Mercury definitions, and
    adding foreign definitions. It specializes each predicate to its task,
    and simplifies its decision flow. It also delegates the creation of
    (most) error messages to separate predicates. Together, these changes
    make each of module_add_type_defn_{abstract,mercury,foreign} easily
    understandable.

    Generate a warning if a type is declared twice, i.e. if e.g.
    ":- type x." is followed by another ":- type x.".

    Call module_info_incr_errors to register the presence of errors in just
    one central place. (Before, some of the places that generated error
    messages incremented the error count, and some places didn't.)

    Improve the wording of some error messages.

    Refer to type names in error messages by unqualified sym_names
    in cases where the module qualifier being elided is obvious from
    the name of the module being compiled.

    Add documentation.

    Add descriptions of potential future improvements.

    Add some XXXs at places that I think deserve them.

    Give some predicates and variables better names.

compiler/prog_data.m:
    Change the parse tree representation of type definitions by
    explicitly specifying a type for storing the contents of each kind
    of type definition.

compiler/hlds_data.m:
    Give a predicate a better name.

    Use one of the new types in prog_data.m in the HLDS version of type
    definitions, to minimize differences between the parse tree and HLDS
    versions.

compiler/add_foreign_enum.m:
compiler/add_pragma.m:
compiler/add_special_pred.m:
compiler/check_typeclass.m:
compiler/du_type_layout.m:
compiler/equiv_type.m:
compiler/equiv_type_hlds.m:
compiler/foreign.m:
compiler/get_dependencies.m:
compiler/hlds_code_util.m:
compiler/hlds_out_module.m:
compiler/inst_check.m:
compiler/intermod.m:
compiler/item_util.m:
compiler/make_hlds_passes.m:
compiler/make_hlds_separate_items.m:
compiler/make_tags.m:
compiler/ml_type_gen.m:
compiler/ml_unify_gen.m:
compiler/module_qual.qualify_items.m:
compiler/parse_pragma.m:
compiler/parse_tree_out.m:
compiler/parse_type_defn.m:
compiler/post_term_analysis.m:
compiler/recompilation.check.m:
compiler/recompilation.usage.m:
compiler/recompilation.version.m:
compiler/resolve_unify_functor.m:
compiler/simplify_goal_ite.m:
compiler/special_pred.m:
compiler/switch_util.m:
compiler/term_norm.m:
compiler/type_ctor_info.m:
compiler/type_util.m:
compiler/unify_proc.m:
compiler/unused_imports.m:
compiler/write_module_interface_files.m:
compiler/xml_documentation.m:
    Conform to the changes in prog_data.m.

library/io.m:
library/store.m:
    Delete duplicate type declarations that add_type.m now complains about.

tests/invalid/bad_foreign_type.{m,err_exp}:
    Extend this test to test the new warning.

    Expect the updated versions of some error messages.

tests/invalid/extra_info_prompt.err_exp:
tests/invalid/foreign_type_visibility.err_exp:
tests/invalid/user_eq_dummy.err_exp:
    Expect the updated versions of some error messages.
2017-06-27 18:15:58 +02:00
Zoltan Somogyi
4ebc3ffa04 Carve four modules out of prog_data.m.
The prog_data.m module is imported by most modules of the compiler; by
359 modules out of 488, to be exact. Yet it has many parts that most of
those 359 modules don't need. This diff puts those parts into four new
modules. The number of imports of these modules:

    348 modules import prog_data.m
     84 modules import prog_data_foreign.m
     62 modules import prog_data_pragma.m
     12 modules import prog_data_event.m
      5 modules import prog_data_used_modules.m

compiler/prog_data_event.m:
compiler/prog_data_foreign.m:
compiler/prog_data_pragma.m:
compiler/prog_data_used_modules.m:
    New modules. They contain the parts of the parse tree that deal
    respectively with the specification of events and event sets,
    interfacing to foreign languages, pragmas, and the sets of used
    (i.e. not unused) modules.

compiler/prog_data.m:
    Delete the stuff that is now in the new modules. Put the remaining parts
    of the module into a logical order.

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

compiler/globals.m:
    Move a type here from prog_data.m, since this is where it belongs.

compiler/add_foreign_proc.m:
compiler/add_mutable_aux_preds.m:
compiler/add_pragma.m:
compiler/add_solver.m:
compiler/add_trail_ops.m:
compiler/call_gen.m:
compiler/code_gen.m:
compiler/code_loc_dep.m:
compiler/comp_unit_interface.m:
compiler/compile_target_code.m:
compiler/complexity.m:
compiler/continuation_info.m:
compiler/coverage_profiling.m:
compiler/ctgc.datastruct.m:
compiler/ctgc.livedata.m:
compiler/ctgc.selector.m:
compiler/deep_profiling.m:
compiler/dep_par_conj.m:
compiler/deps_map.m:
compiler/det_analysis.m:
compiler/det_report.m:
compiler/elds_to_erlang.m:
compiler/equiv_type.m:
compiler/erl_call_gen.m:
compiler/exception_analysis.m:
compiler/export.m:
compiler/fact_table.m:
compiler/foreign.m:
compiler/frameopt.m:
compiler/get_dependencies.m:
compiler/goal_form.m:
compiler/goal_util.m:
compiler/granularity.m:
compiler/hlds_goal.m:
compiler/hlds_module.m:
compiler/hlds_out_goal.m:
compiler/hlds_out_module.m:
compiler/hlds_out_pred.m:
compiler/hlds_pred.m:
compiler/inlining.m:
compiler/intermod.m:
compiler/ite_gen.m:
compiler/item_util.m:
compiler/jumpopt.m:
compiler/layout.m:
compiler/layout_out.m:
compiler/live_vars.m:
compiler/livemap.m:
compiler/llds.m:
compiler/llds_out_file.m:
compiler/llds_out_global.m:
compiler/llds_out_instr.m:
compiler/make.dependencies.m:
compiler/make.module_dep_file.m:
compiler/make_hlds.m:
compiler/make_hlds_warn.m:
compiler/mark_tail_calls.m:
compiler/mercury_compile_llds_back_end.m:
compiler/mercury_compile_main.m:
compiler/ml_call_gen.m:
compiler/ml_code_gen.m:
compiler/ml_code_util.m:
compiler/ml_foreign_proc_gen.m:
compiler/ml_proc_gen.m:
compiler/ml_tailcall.m:
compiler/ml_unify_gen.m:
compiler/mlds.m:
compiler/mlds_to_c.m:
compiler/mlds_to_cs.m:
compiler/mlds_to_java.m:
compiler/modecheck_goal.m:
compiler/module_imports.m:
compiler/module_qual.m:
compiler/module_qual.qualify_items.m:
compiler/modules.m:
compiler/opt_debug.m:
compiler/par_conj_gen.m:
compiler/parse_pragma.m:
compiler/parse_tree_out_info.m:
compiler/parse_tree_out_pragma.m:
compiler/pd_cost.m:
compiler/polymorphism.m:
compiler/pragma_c_gen.m:
compiler/proc_gen.m:
compiler/prog_ctgc.m:
compiler/prog_event.m:
compiler/prog_foreign.m:
compiler/prog_item.m:
compiler/prog_out.m:
compiler/prog_util.m:
compiler/purity.m:
compiler/rbmm.points_to_analysis.m:
compiler/rbmm.points_to_graph.m:
compiler/simplify_goal_call.m:
compiler/simplify_goal_scope.m:
compiler/simplify_proc.m:
compiler/smm_common.m:
compiler/stack_layout.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_sharing.analysis.m:
compiler/structure_sharing.domain.m:
compiler/table_gen.m:
compiler/tabling_analysis.m:
compiler/term_constr_build.m:
compiler/term_constr_initial.m:
compiler/term_constr_main.m:
compiler/term_constr_main_types.m:
compiler/term_constr_pass2.m:
compiler/term_constr_util.m:
compiler/term_errors.m:
compiler/term_pass1.m:
compiler/term_pass2.m:
compiler/term_traversal.m:
compiler/term_util.m:
compiler/termination.m:
compiler/trace_gen.m:
compiler/trailing_analysis.m:
compiler/type_constraints.m:
compiler/typecheck.m:
compiler/unique_modes.m:
compiler/unused_args.m:
compiler/unused_imports.m:
compiler/use_local_vars.m:
compiler/write_deps_file.m:
    Conform to the changes above.
2016-03-13 18:19:31 +11:00
Zoltan Somogyi
5251d1fdd6 Add `:- pragma consider_used(predname/arity)'.
Sometimes, one wants to keep some predicates around even if they are not
currently being used. Adding this pragma for such a predicate will shut up
dead procedure/predicate warnings both for the named predicate and for the
other predicates it calls, both directly and indirectly.

With two of these pragmas added to compiler/stratify.m, the number of
predicates being reported as dead goes from 25 to 0.

compiler/prog_item.m:
    Define the new pragma.

compiler/prog_io_pragma.m:
    Parse the new pragma.

compiler/parse_tree_out_pragma.m:
    Write out the new pragma, if needed.

compiler/add_pragma.m:
    Add the new pragma to the HLDS in the form of a marker on the named
    predicate.

compiler/hlds_pred.m:
    Define that marker.

compiler/dead_proc_elim.m:
    If a predicate has that marker, consider all its procedures to be live.

compiler/comp_unit_interface.m:
compiler/equiv_type.m:
compiler/get_dependencies.m:
compiler/hlds_out_pred.m:
compiler/intermod.m:
compiler/item_util.m:
compiler/make_hlds_separate_items.m:
compiler/module_qual.qual_errors.m:
compiler/module_qual.qualify_items.m:
compiler/prog_item_stats.m:
compiler/recompilation.version.m:
compiler/table_gen.m:
compiler/write_module_interface_files.m:
    Conform to the changes above.

tests/invalid/bad_consider_used.{m,err_exp}:
    New test case to test the handling of invalid consider_used pragmas.

tests/invalid/Mmakefile:
    Add the new test case.
2015-12-14 11:36:43 +11:00
Paul Bone
c6cbc43448 Add new require_tail_recursion pragma.
This patch allows the pragma to be parsed, and records the information from
the pragma in the proc_info structure for the relevant procedures.

The patch uses the pragma for the MLDS backend.  However because mutual
recursion is not yet supported on the MLDS backend, mutually recursive calls
are ignored by the pragma.

The patch also documents the pragma in the reference manual, this
documentation is commented out until it is implemented for both LLDS and
MLDS backends.

The patch does not implement the SCC feature discussed on the mailing list.
That can be added later.

compiler/prog_data.m:
compiler/prog_item.m:
    Add new require_tail_recursion pragma.

compiler/prog_io_pragma.m:
    Parse the new pragma.

    Remove the arity_and_modes type and use pred_name_arity_mpf_mmode
    type from prog_item.m

compiler/parse_tree_out_pragma.m:
    Support pretty printing the new pragma.

compiler/hlds_pred.m:
    Add require_tailrec_info to the proc_info structure.

compiler/add_pragma.m:
    Add information from the pragma to the proc_info structure after
    parsing.

compiler/compiler_util.m:
    Add a general warning_or_error type.

compiler/mlds.m:
    Add require_tailrec_info to MLDS functions.

compiler/ml_proc_gen.m:
    Copy the require_tailrec_info information from the HLDS to the MLDS.

compiler/ml_tailcall.m:
    Generate errors and warnings with respect to the require_tail_recursion
    pragma.

compiler/mercury_compile.m:
compiler/mercury_compile_mlds_back_end.m:
    Return errors from the MLDS tailcall optimisation pass.

compiler/add_pragma.m:
compiler/comp_unit_interface.m:
compiler/equiv_type.m:
compiler/get_dependencies.m:
compiler/item_util.m:
compiler/make_hlds_separate_items.m:
compiler/module_qual.qual_errors.m:
compiler/module_qual.qualify_items.m:
compiler/prog_item_stats.m:
compiler/recompilation.version.m:
compiler/write_module_interface_files.m:
    Conform to changes in prog_item.m.

compiler/ml_code_util.m:
compiler/ml_elim_nested.m:
compiler/ml_optimize.m:
compiler/ml_type_gen.m:
compiler/ml_util.m:
compiler/mlds_to_c.m:
compiler/mlds_to_cs.m:
compiler/mlds_to_java.m:
    Conform to changes in mlds.m.

doc/reference_manual.texi
    Document the require_tail_recursion pragma

tests/invalid/Mercury.options:
tests/invalid/Mmakefile:
tests/invalid/require_tail_recursion.err_exp:
tests/invalid/require_tail_recursion.m:
    Add require_tail_recursion test case
2015-12-08 22:54:59 +11:00
Zoltan Somogyi
62ec97d443 Report imports shadowed by other imports.
If a module has two or more import_module or use_module declarations
for the same module, (typically, but not always, one being in its interface
and one in its implementation), generate an informational message about
each redundant declaration if --warn-unused-imports is enabled.

compiler/hlds_module.m:
    We used to record the set of imported/used modules, and the set of
    modules imported/used in the interface of the current module. However,
    these sets

    - did not record the distinction between imports and uses;
    - did not allow distinction between single and multiple imports/uses;
    - did not record the locations of the imports/uses.

    The first distinction was needed only by module_qual.m, which *did*
    pay attention to it; the other two were not needed at all.

    To generate messages for imports/uses shadowing other imports/uses,
    we need all three, so change the data structure storing such information
    for *direct* imports to one that records all three of the above kinds
    of information. (For imports made by read-in interface and optimization
    files, the old set of modules approach is fine, and this diff leaves
    the set of thus *indirectly* imported module names alone.)

compiler/unused_imports.m:
    Use the extra information now available to generate a
    severity_informational message about any import or use that is made
    redundant by an earlier, more general import or use.

    Fix two bugs in the code that generated warnings for just plain unused
    modules.

    (1) It did not consider that a use of the builtin type char justified
    an import of char.m, but without that import, the type is not visible.

    (2) It scanned cons_ids in goals in procedure bodies, but did not scan
    cons_ids that have been put into the const_struct_db. (I did not update
    the code here when I added the const_struct_db.)

    Also, add a (hopefully temporary) workaround for a bug in
    make_hlds_passes.m, which is noted below.

    However, there are at least three problems that prevent us from enabling
    --warn-unused-imports by default.

    (1) In some places, the import of a module is used only by clauses for
    a predicate that also has foreign procs. When compiled in a grade that
    selects one of those foreign_procs as the implementation of the predicate,
    the clauses are discarded *without* being added to the HLDS at all.
    This leads unused_imports.m to generate an uncalled-for warning in such
    cases. To fix this, we would need to preserve the Mercury clauses for
    *all* predicates, even those with foreign procs, and do all the semantic
    checks on them before throwing them away. (I tried to do this once, and
    failed, but the task should be easier after the item list change.)

    (2) We have two pieces of code to generate import warnings. The one in
    unused_imports.m operates on the HLDS after type and mode checking,
    while module_qual.m operates on the parse tree before the creation of
    the HLDS. The former is more powerful, since it knows e.g. what types and
    modes are used in the bodies of predicates, and hence can generate warnings
    about an import being unused *anywhere* in a module, as opposed to just
    unused in its interface.

    If --warn-unused-imports is enabled, we will get two separate set of
    reports about an interface import being unused in the interface,
    *unless* we get a type or mode error, in which case unused_imports.m
    won't be invoked. But in case we do get such errors, we don't want to
    throw away the warnings from module_qual.m. We could store them and
    throw them away only after we know we won't need them, or just get
    the two modules to generate identical error_specs for each warning,
    so that the sort_and_remove_dups of the error specs will do the
    throwing away for us for free, if we get that far.

    (3) The valid/bug100.m test case was added as a regression test for a bug
    that was fixed in module_qual.m. However the bug is still present in
    unused_imports.m.

compiler/make_hlds_passes.m:
    Give hlds_module.m the extra information it now needs for each item_avail.

    Add an XXX for a bug that cannot be fixed right now: the setting of
    the status of abstract instances to abstract_imported. (The "abstract"
    part is correct; the "imported" part may not be.)

compiler/intermod.m:
compiler/try_expand.m:
compiler/xml_documentation.m:
    Conform to the change in hlds_module.m.

compiler/module_qual.m:
    Update the documentation of the relationship of this module
    with unused_imports.m.

compiler/hlds_data.m:
    Document a problem with the status of instance definitions.

compiler/hlds_out_module.m:
    Update the code that prints out the module_info to conform to the change
    to hlds_module.m.

    Print status information about instances, which was needed to diagnose
    one of the bugs in unused_imports.m. Format the output for instances
    nicer.

compiler/prog_item.m:
    Add a convenience predicate.

compiler/prog_data.m:
    Remove a type synonym that makes things harder to understand, not easier.

compiler/modules.m:
    Delete an XXX that asks for the feature this diff implements.
    Add another XXX about how that feature could be improved.

compiler/Mercury.options.m:
    Add some more modules to the list of modules on which the compiler
    should be invoked with --no-warn-unused-imports.

compiler/*.m:
library/*.m:
mdbcomp/*.m:
browser/*.m:
deep_profiler/*.m:
mfilterjavac/*.m:
    Delete unneeded imports. Many of these shadow other imports, and some
    are just plain unneeded, as shown by --warn-unused-imports. In a few
    modules, there were a *lot* of unneeded imports, but most had just
    one or two.

    In a few cases, removing an import from a module, because it *itself*
    does not need it, required adding that same import to those of its
    submodules which *do* need it.

    In a few cases, conform to other changes above.

tests/invalid/Mercury.options:
    Test the generation of messages about import shadowing on the existing
    import_in_parent.m test case (although it was also tested very thoroughly
    when giving me the information needed for the deletion of all the
    unneeded imports above).

tests/*/*.{m,*exp}:
    Delete unneeded imports, and update any expected error messages
    to expect the now-smaller line numbers.
2015-08-25 00:38:49 +10:00
Zoltan Somogyi
a4b3c6f546 Simplify the code that makes some items abstract for interfaces.
compiler/comp_unit_interface.m:
compiler/write_module_interface_files.m:
    Each of these modules have code that decided which items to include
    in interface, either in their original form, or abstracted. Both pieces
    of code used to executed three switches in sequence on the same item.
    The overall effect was the composition of the three switches, but
    readers of the code had to do this composition in their head
    if they wanted to understand the code.

    Replace both three-switch sequences with a single switch, mainly to make
    the effect of the code immediately obvious to the reader, and to eliminate
    the dead code we used to have, when an earlier switch (the first, or
    maybe second) decided the outcome, and it didn't matter what the later
    (maybe the second, definitely the third) switches did.

    The new code does fewer tests, but allocates more memory. The net
    performance effect seems to be a wash. (In two different speed tests,
    I got one speedup and one slowdown. Strangely, eliminating the extra
    memory allocation led to slowdown.)

    There are enough differences between how these two modules make their
    decisions that I don't see a useful way to factor out the commonalities
    in their needs.

compiler/item_util.m:
    Replace the utility predicates needed by the three-switch approach
    with the ones needed by the new single switch approach.
2015-08-12 10:22:18 +10:00