Commit Graph

194 Commits

Author SHA1 Message Date
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
5bb13084f0 Eliminate unneeded work in arg_info.m.
compiler/arg_info.m:
    We used to iterate over all the pred_ids in the module,
    with each iteration

    - looking up the pred_info in the module_info,
    - updating the pred_info, and then
    - putting the pred_info back into the module_info.

    Avoid all these lookups and module_info updates by

    - converting the pred_table to an assoc_list of pred_ids and pred_infos,
    - iterating over it, creating an updated assoc_list,
    - converting the updated assoc_list back into the pred_table.

    Make the same change on the code that updates proc_infos inside pred_infos.

    Look up the value the use_float_registers option just once, instead of
    once per procedure.

    Instead of always using a predicate, make_arg_infos, that iterates
    on three lists simultaneously, creating the third list either from
    constants or one of the other lists, create and use two specialized
    versions of make_arg_infos, one for each of those use cases. This should
    reduce both memory turnover and execution time.

    Put the arguments of some predicates (both exported and private)
    into a better order.

compiler/export.m:
compiler/tupling.m:
    Conform to the changes above.
2022-04-01 06:42:56 +11:00
Zoltan Somogyi
8ebe125a6a Introduce var_table.m.
Most compiler passes need to know both the names and the types
of the variables they operate on. Until now, they had to pass along
two separate data structures for that, the varset and the vartypes,
and many operations required looking a variable up in both of these.

The var table is a single data structure that records for each variable

- its name, as the varset has traditionally done,
- its type, as the vartypes has traditionally done,
- the is_dummy_type flag which says whether its type is a dummy type,
  which traditionally had to computed afresh at each lookup.

Switch the MLDS code generator to use var_tables instead of varsets and
vartypes. The code generator often needs to know the name and the type
of a variable at the same time, and it often needs to know which variables'
types are dummies, often enough that precomputing this info should be a win.

compiler/var_table.m:
    Add this new module which defines the var_table.

    Its operations are modelled after the operation in var_types.m.

compiler/hlds.m:
compiler/notes/compiler_design.html:
    Add the new module to the hlds package.

compiler/prog_type.m:
compiler/type_util.m:
    Move the is_dummy_type from type_util.m, which is in the
    check_hlds package, to prog_type.m, which in the parse_tree package,
    to avoid having this part of the hlds package depend on check_hlds.
    (It already depends on parse_tree, for a lot of different things.)

    Given a function and a predicate that each took a vartypes arg,
    make new versions that take a var_table arg instead.
    Rationalize the argument list of the function.

compiler/ml_gen_info.m:
    Replace the varset and vartypes fields of the ml_gen_info with a
    var_table field.

compiler/ml_code_util.m:
    Replace code that used to operate on varsets and vartypes with code
    that operates on var_tables.

    Create new versions of a few operations to exploit the info in var_tables.

    Give some predicates more meaningful names.

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_commit_gen.m:
compiler/ml_disj_gen.m:
compiler/ml_foreign_proc_gen.m:
compiler/ml_lookup_switch.m:
compiler/ml_proc_gen.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:
    Replace code that used to operate on varsets and vartypes with code
    that operates on var_tables.

    In ml_switch_gen.m and ml_tag_switch.m, put some predicates' arguments
    into an reasonable order by moving related args next to each other.

compiler/vartypes.m:
    Delete an operation that was only needed in the MLDS backend,
    in code that this diff replaces.

compiler/switch_util.m:
    Put the larger input first in the arg list of a predicate.

compiler/closure_gen.m:
compiler/code_info.m:
compiler/code_loc_dep.m:
compiler/export.m:
compiler/lambda.m:
compiler/live_vars.m:
compiler/liveness.m:
compiler/llds.m:
compiler/llds_out_instr.m:
compiler/mark_tail_calls.m:
compiler/opt_debug.m:
compiler/opt_util.m:
compiler/stack_alloc.m:
compiler/stack_layout.m:
compiler/tag_switch.m:
compiler/term_constr_util.m:
compiler/tupling.m:
compiler/unify_gen.m:
compiler/unify_gen_deconstruct.m:
compiler/var_locn.m:
    Conform to the changes above.
2022-03-28 10:20:49 +11:00
Zoltan Somogyi
25b4b67403 Carve io.file.m out of io.m.
library/io.file.m:
library/io.m:
    Move two sections of io.m, the "file handling predicates" section
    and the "handling temporary files" section to the new submodule io.file.m.

    Leave behind in io.m "forwarding predicates", predicates that do nothing
    except call the moved predicates in io.file.m, to provide backward
    compatibility. But do mark the forwarding predicates as obsolete,
    to tell people to update their (at their leisure, since the obsoleteness
    warning can be turned off).

    Also leave behind in io.m the definitions of the two types used
    by some parameters of some of the moved predicates. Document the reason
    why this is done.

library/MODULES_DOC:
    List the new module among the documented modules.

NEWS:
    Announce the changes.

browser/browse.m:
browser/interactive_query.m:
browser/listing.m:
compiler/analysis.file.m:
compiler/compile_target_code.m:
compiler/export.m:
compiler/fact_table.m:
compiler/file_util.m:
compiler/handle_options.m:
compiler/make.build.m:
compiler/make.module_dep_file.m:
compiler/make.module_target.m:
compiler/make.program_target.m:
compiler/make.util.m:
compiler/mercury_compile_main.m:
compiler/module_cmds.m:
compiler/parse_module.m:
compiler/passes_aux.m:
compiler/prog_event.m:
compiler/recompilation.check.m:
compiler/write_deps_file.m:
compiler/write_module_interface_files.m:
deep_profiler/conf.m:
deep_profiler/mdprof_cgi.m:
library/dir.m:
mdbcomp/program_representation.m:
ssdb/ssdb.m:
    Call the file operation predicates directly in io.file.m, not indirectly
    through io.m.

    In two modules, add a #include of fcntl.h in C code. These modules contain
    C code that needs this #include, but until now, they got it via a copy
    in an automatically generated C header file of a foreign_decl pragma
    in io.m that contained that #include. This diff moves that foreign_decl
    to io.file.m, removing that crutch.

tests/debugger/browser_test.m:
tests/hard_coded/bit_buffer_test.m:
tests/hard_coded/bitmap_test.m:
tests/hard_coded/construct_bug.m:
tests/hard_coded/dir_fold.m:
tests/hard_coded/dir_test.m:
tests/hard_coded/read_binary_int16.m:
tests/hard_coded/read_binary_int32.m:
tests/hard_coded/read_binary_int64.m:
tests/hard_coded/read_binary_uint16.m:
tests/hard_coded/read_binary_uint32.m:
tests/hard_coded/read_binary_uint64.m:
tests/hard_coded/read_bitmap_size.m:
tests/hard_coded/remove_file.m:
tests/hard_coded/write_binary.m:
tests/hard_coded/write_binary_int8.m:
tests/hard_coded/write_binary_multibyte_int.m:
tests/hard_coded/write_binary_uint8.m:
    Call the file operation predicates directly in io.file.m, not indirectly
    through io.m.
2022-03-08 06:01:21 +11:00
Zoltan Somogyi
5cada10369 Rename pred_table to pred_id_table.
compiler/pred_table.m:
    As above. This addresses half of an old XXX, which is that the two types
    defined in this module, predicate_table and pred_table (as it was then)
    should have names that (a) say what they do, and (b) are distinct.
    Addressing the other half requires a more descriptive but not-too-long
    name to replace "predicate_table".

    Rename the predicates that operate on the type to follow the name change.

    Add a distinguishing prefix to the names of the fields of the
    predicate_table type.

compiler/add_clause.m:
compiler/add_foreign_proc.m:
compiler/add_pragma.m:
compiler/add_pragma_tabling.m:
compiler/add_pragma_type_spec.m:
compiler/add_pred.m:
compiler/add_special_pred.m:
compiler/arg_info.m:
compiler/bytecode_gen.m:
compiler/clause_to_proc.m:
compiler/closure_gen.m:
compiler/cse_detection.m:
compiler/dead_proc_elim.m:
compiler/deep_profiling.m:
compiler/default_func_mode.m:
compiler/det_analysis.m:
compiler/det_util.m:
compiler/direct_arg_in_out.m:
compiler/distance_granularity.m:
compiler/export.m:
compiler/float_regs.m:
compiler/goal_mode.m:
compiler/granularity.m:
compiler/hlds_defns.m:
compiler/hlds_error_util.m:
compiler/hlds_module.m:
compiler/hlds_out_goal.m:
compiler/hlds_out_module.m:
compiler/hlds_out_util.m:
compiler/hlds_pred.m:
compiler/hlds_statistics.m:
compiler/implementation_defined_literals.m:
compiler/inlining.m:
compiler/intermod.m:
compiler/introduce_exists_casts.m:
compiler/introduce_parallelism.m:
compiler/lambda.m:
compiler/lco.m:
compiler/make_hlds_passes.m:
compiler/mark_tail_calls.m:
compiler/mercury_compile_llds_back_end.m:
compiler/ml_proc_gen.m:
compiler/mode_info.m:
compiler/modecheck_call.m:
compiler/modes.m:
compiler/oisu_check.m:
compiler/old_type_constraints.m:
compiler/passes_aux.m:
compiler/polymorphism.m:
compiler/polymorphism_post_copy.m:
compiler/post_typecheck.m:
compiler/pre_typecheck.m:
compiler/proc_gen.m:
compiler/proc_requests.m:
compiler/simplify_proc.m:
compiler/stm_expand.m:
compiler/structure_reuse.analysis.m:
compiler/structure_reuse.direct.m:
compiler/structure_sharing.analysis.m:
compiler/switch_detection.m:
compiler/table_gen.m:
compiler/term_constr_build.m:
compiler/term_constr_initial.m:
compiler/term_constr_util.m:
compiler/term_util.m:
compiler/termination.m:
compiler/typecheck.m:
compiler/typecheck_errors.m:
compiler/typecheck_info.m:
compiler/unused_args.m:
compiler/unused_imports.m:
compiler/xml_documentation.m:
    Conform to the change in pred_table.m.

    Refer to values of the renamed type using a consistent naming scheme.

    When the affected code repeats the body of existing helper predicates
    for lookup up a pred_info or proc_info, or updating a proc_info
    inside a pred_info, or updating a pred_info inside a module_info,
    call the helper predicate instead. This makes code shorter and less
    cluttered, and the use of the helper predicates for updates automatically
    ensures that we don't accidentally update a stale version of the relevant
    table. (This has sometimes been a problem in the past.)

    In a few places, carve a new predicate for processing one element
    of a list out of an existing predicate for processing all list elements.
2022-02-03 10:01:21 +11:00
Zoltan Somogyi
703f52fd7a Stop using exit status to report success/failure.
compiler/make.module_dep_file.m:
    Judge whether calls to write_short_interface_file_int3 succeeded
    by an explicit maybe_succeeded value they now return, instead of
    checking the exit status in the I/O state.

compiler/module_cmds.m:
compiler/parse_tree_out.m:
compiler/write_module_interface_files.m:
    Make operations on files return a maybe_succeeded argument to indicate
    success vs failure.

compiler/make.module_target.m:
compiler/mlds_to_c_file.m:
    Take the new maybe_succeeded arguments in calls into account
    when computing whether an action succeeded.

compiler/analysis.m:
compiler/export.m:
compiler/mercury_compile_front_end.m:
compiler/mercury_compile_main.m:
compiler/mercury_compile_middle_passes.m:
compiler/recompilation.check.m:
    Ignore the maybe_succeeded results returned by calls, for now.

    In export.m, switch from /* */ to // syntax for the C comments we write.
2021-08-23 22:07:14 +10:00
Zoltan Somogyi
21574b7c8f Separate semantic checks on fact table preds ...
from code generation for them.

compiler/fact_table.m:
    Add a separate predicate to do all the required type and mode checks
    on the fact table predicate and all its procedures. If this finds errors,
    return error messages describing them. If there are no errors, then return
    a data structure containing all the semantic information that later passes
    will need, which records both type and mode information in a form
    in which unsupported types and modes cannot be represented.

    Significantly improve the text of most error messages.

    Rewrite large chunks of this module to use this data structure (GenInfo)
    instead of the predicate's arg types and the procedure's arg modes,
    since the latter could not be used without effectively being checked
    for validity over and over again. The rewrite of the call tree of the
    first exported pred also cuts out of it the semantic checks that are
    now in their own pass.

    Replace some uses of the ok/error type with empty/nonempty lists
    of error_specs.

    Replace several uses of bools with bespoke types.

    In several related predicates, replace a flag argument and a set of
    other arguments that were meaningful only with one setting of the flag
    with a maybe-like type that specified those other arguments only when
    needed.

    Use the tight new types to replace some if-then-else chains
    with switches.

    Move the task of generating the pragma_vars and the prog_varset
    of the foreign_proc implementing each procedure from add_pragma.m
    to here, to let fact_table.m control this aspect of the foreign_proc
    along with all the others.

    Reorder several argument vectors to put bigger/slower-moving inputs
    first.

compiler/add_pragma.m:
    If a fact table pragma is for a predicate that whose declarations
    are not compatible with fact tables, then do not try to generate
    those fact tables, but do record the presence of the error.

    Don't do work that is now done in fact_table.m.

    Reorder several argument vectors to put bigger/slower-moving inputs
    first.

compiler/hlds_pred.m:
    Provide a mechanism for add_pragma to record the presence of those errors.

compiler/typecheck_errors.m:
    If a predicate has a fact_table for it, then its clauses (actually,
    foreign_procs) are supposed to be provided by the compiler;
    the absence of user-supplied clauses is to be expected.
    If, due to incompatibility between the predicate's declarations
    and the requirements of fact tables, the compiler cannot generate
    those foreign_procs, do not generate an error message about
    the absence of clauses, since such an error message would be misleading.
    The problem *will* be reported by fact_table.m.

compiler/hlds_out_pred.m:
compiler/intermod.m:
compiler/table_gen.m:
    Conform to the change in hlds_pred.m.

compiler/export.m:
    Note the fact that fact_table.m now contains cut-down versions
    of two of the predicates here.

tests/invalid/bad_fact_table_decls.{m,err_exp}:
    A new test case testing the error messages involving problems
    with the type and mode declarations of fact table predicates.

tests/invalid/bad_fact_table_data.{m,err_exp}:
tests/invalid/fact_table_data_file_x:
    A new test case testing the error messages involving problems
    with the contents of fact table files.

tests/invalid/Mmakefile:
    Enable the two new test cases.
2021-06-11 12:48:26 +10:00
Zoltan Somogyi
93c306916a Specify streams explicitly in more modules.
compiler/module_cmds.m:
    Require all callers to specify output streams explicitly.

compiler/compile_target_code.m:
    Require callers to specify output streams explicitly in most cases.

    In the remaining cases, add "XXX STREAM" comments to request that
    the explicit streams be passed later.

    Add XXXs where preserving old behavior results in wrong-looking code.

    Modify the signature of compile_java_files to encode the invariant that
    the list of Java files given to it may not be empty.

compiler/error_util.m:
    Provide a version of an error predicate that takes explicit streams.

compiler/make.build.m:
    Mark predicates that help redirect implicit streams as predicates
    that should not be used.

compiler/make.module_target.m:
compiler/make.program_target.m:
    Add "XXX STREAM" comments to request that the explicit streams
    be passed later.

compiler/module_qual.m:
    Provide a means to construct the debug output stream.

compiler/module_qual.collect_mq_info.m:
    Use the debug output stream where relevant.

compiler/analysis.m:
compiler/export.m:
compiler/recompilation.check.m:
compiler/source_file_map.m:
compiler/write_module_interface_files.m:
compiler/xml_documentation.m:
    Conform to the changes above, mostly by passing explicit streams.

compiler/Mercury.options:
    Stop specifying --no-warn-implicit-stream-calls for the above modules
    (those that had it specified in the first place).

    Delete a long-unneeded workaround.

compiler/mercury_compile_front_end.m:
compiler/mercury_compile_llds_back_end.m:
compiler/mercury_compile_main.m:
compiler/mercury_compile_middle_passes.m:
    Specify progress and output streams explicitly when calling the modules
    above (not in other places, just yet).
2021-05-17 22:55:06 +10:00
Zoltan Somogyi
4455f0450e Specify output streams in some places.
Besides this main purpose, this diff also replaces code that calls
io.write_string several times in a row with code that prints the
thing to be printed in one go with io.format. In a couple of places,
this has caught (and fixed) bugs where we wanted to put `' quotes
around a filename, but printed only one of the two quotes.

compiler/file_util.m:
    Provide alternatives to the existing maybe_report_stats,
    maybe_write_string and maybe_flush_output predicates that explicitly
    specify the output stream.

    Rename report_error_to_stream as report_error, to allow
    --warn-implicit-stream-calls to report calls to the existing report_error
    predicate, which does not take an explicit output stream.

    Add a module_name argument to the output_to_file_stream predicate,
    to allow its code to figure out where to print both progress and
    error messages.

compiler/module_cmds.m:
    Add a module_name argument to the predicates that update interface,
    to allow their code to figure out where to print both progress and
    error messages.

    For now, leave the predicates that issue commands that are not
    clearly linked to a single module using implicit streams.

compiler/pd_debug.m:
compiler/analysis.file.m:
    Specify output streams in some places.

    In other places, doing so would require redoing the whole debug
    infrastructure, since the current one is based on higher order predicates
    that always write to the non-explicitly-specified *current* output stream.

compiler/passes_aux.m:
    Provide predicates that get progress, debug and error streams
    given a module_info, by extracting the globals and the module name
    from the module_info, and then calling the predicates in globals.m
    to get those streams. Doing this sequence of actions here factors out
    what would otherwise be repeated code in many other parts of the compiler.

    Delete two predicates that were not used anywhere in the compiler.

compiler/deforest.m:
compiler/export.m:
compiler/intermod.m:
compiler/llds_out_file.m:
compiler/mlds_to_c_file.m:
compiler/mlds_to_cs_file.m:
compiler/mlds_to_java_file.m:
compiler/recompilation.usage.m:
compiler/simplify_goal_conj.m:
compiler/type_assign.m:
compiler/typecheck.m:
compiler/write_deps_file.m:
compiler/write_module_interface_files.m:
    Use explicit streams everywhere where --warn-implicit-stream-calls
    says this is possible.

compiler/Mercury.options:
    Specify --warn-implicit-stream-calls for the modules above
    with the listed exceptions, and with the exception of the modules
    for which it was already specified.

compiler/compile_target_code.m:
compiler/mercury_compile_front_end.m:
compiler/mercury_compile_middle_passes.m:
    Conform to the changes above.
2021-03-21 23:07:59 +11:00
Zoltan Somogyi
5f50259d16 Write to explicitly named streams in many modules.
Right now, most parts of the compiler write to the "current output stream".
This was a pragmatic choice at the time, but has not aged well. The problem
is that the answer to the question "where is the current output stream going?"
is not obvious in *all* places in the compiler (although it is obvious in
most). When using such implicit streams, finding where the output is going
to in a given predicate requires inspecting not just the ancestors of that
predicate, but also all their older siblings (since any of them could have
changed the current stream), *including* their entire call trees. This is
usually an infeasible task. By constrast, if we explicitly pass streams
to all output operations, we need only follow the places where the variable
representing that stream is bound, which the mode system makes easy.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

library/term_io.m:
    Fix documentation.
2020-11-14 15:07:55 +11:00
Zoltan Somogyi
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
9c00b54152 Append ".tmp" to filenames outside file_names.m.
compiler/file_names.m:
    Require callers to append any ".tmp" suffix to filenames before
    calling the predicates in file_names.m. Delete the code handling
    such suffixes.

compiler/compile_target_code.m:
compiler/export.m:
compiler/mercury_compile_front_end.m:
compiler/mercury_compile_middle_passes.m:
    Call file_names.m without the ".tmp" suffix, and add it after return.
2020-08-18 06:37:51 +10:00
Zoltan Somogyi
c2f92d5454 Partition extensions into ".m" and "all others".
This is a first step towards a much finer grained partition.

compiler/file_names.m:
    Split the ext type into ext_src and ext_other, as mentioned above.

    Add the first predicate for checking whether a string falls into
    a given category of extensions.

    Add an XXX proposing a better solution for an old problem that does not
    actually arise in practice.

compiler/compile_target_code.m:
    Split the two-moded predicate maybe_pic_object_file_extension into
    two separate one-mode predicates, one for each old mode. The
    implementations of the two modes were already separate, because
    the two modes already did different jobs: while one went from PIC
    to an "extension", the other went from an "extension string" to PIC.
    Until now, "extension" and "extension string" were equivalent;
    after this diff, they aren't anymore.

    Delete an unused argument.

compiler/make.util.m:
    Split the two-moded predicate target_extension into
    two separate one-mode predicates, one for each old mode,
    for the same reason as maybe_pic_object_file_extension above:
    the fact that "extension" and "extension string" are now distinct.

compiler/options_file.m:
    Move debug infrastructure here from mercury_compile_main.m, to help
    debug possible problems with options files. (I had such a problem
    while writing this diff.)

    Improve how progress messages are printed.

compiler/options.m:
    Make an error message more useful.

compiler/mercury_compile_main.m:
    Add infrastructure for debugging possible problems with command lines.
    (I had such a problem while writing this diff.)

compiler/analysis.m:
    Conform to the changes above. Put the arguments of some methods
    into the same order as similar predicates in file_names.m.

compiler/find_module.m:
    Conform to the changes above. Delete an unused argument,

compiler/analysis.file.m:
compiler/du_type_layout.m:
compiler/elds_to_erlang.m:
compiler/export.m:
compiler/fact_table.m:
compiler/file_kind.m:
compiler/generate_dep_d_files.m:
compiler/grab_modules.m:
compiler/llds_out_file.m:
compiler/make.build.m:
compiler/make.deps_set.m:
compiler/make.m:
compiler/make.module_dep_file.m:
compiler/make.module_target.m:
compiler/make.program_target.m:
compiler/mercury_compile_front_end.m:
compiler/mercury_compile_llds_back_end.m:
compiler/mercury_compile_middle_passes.m:
compiler/mercury_compile_mlds_back_end.m:
compiler/mlds_to_c_file.m:
compiler/mlds_to_cs_file.m:
compiler/mlds_to_java_file.m:
compiler/mmc_analysis.m:
compiler/mode_constraints.m:
compiler/module_cmds.m:
compiler/prog_foreign.m:
compiler/read_modules.m:
compiler/recompilation.check.m:
compiler/recompilation.usage.m:
compiler/source_file_map.m:
compiler/write_deps_file.m:
compiler/write_module_interface_files.m:
compiler/xml_documentation.m:
2020-08-17 23:43:15 +10:00
Zoltan Somogyi
52c0919975 Make filename extensions a separate type, ...
... to allow later changes to its definition.

compiler/file_names.m:
    We used to represent filename extensions simply as strings. This meant
    all calls to the predicates in file_names.m that convert module names
    to file names with various suffixes had to go through a complicated
    sequence of tests that effectively partition the extensions into
    several classes, with all extensions in a class being treated the same
    but different classes being treated differently. And since this general
    translation process is quite convoluted (which is not helped by it
    being spread across several predicates), it is very hard to construct
    a correctness argument for it.

    It would be better to represent the different classes of extensions
    explicitly, in a du type, with each function symbol of that type
    representing all the extensions in the corresponding class (in the sense
    of the paragraph above). However, getting there in one diff would make
    that diff far too hard to test and to review. So this first diff
    starts by simply making extension a notag type.

    The above is the first step in implementing one old XXX. This diff
    fully implements another old XXX, which is to make the argument order
    of several predicates friendly to higher order code.

    Add infrastructure for profiling how often this code makes directories.

    Delete an unused type.

    Add comments outlining proposed future improvements.

compiler/analysis.file.m:
compiler/analysis.m:
compiler/compile_target_code.m:
compiler/du_type_layout.m:
compiler/elds_to_erlang.m:
compiler/export.m:
compiler/fact_table.m:
compiler/file_kind.m:
compiler/find_module.m:
compiler/generate_dep_d_files.m:
compiler/grab_modules.m:
compiler/llds_out_file.m:
compiler/make.build.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/mercury_compile_front_end.m:
compiler/mercury_compile_llds_back_end.m:
compiler/mercury_compile_main.m:
compiler/mercury_compile_middle_passes.m:
compiler/mercury_compile_mlds_back_end.m:
compiler/mlds_to_c_file.m:
compiler/mlds_to_cs_file.m:
compiler/mlds_to_java_file.m:
compiler/mmc_analysis.m:
compiler/mode_constraints.m:
compiler/module_cmds.m:
compiler/module_imports.m:
compiler/parse_tree_out.m:
compiler/prog_foreign.m:
compiler/read_modules.m:
compiler/recompilation.check.m:
compiler/recompilation.usage.m:
compiler/write_deps_file.m:
compiler/write_module_interface_files.m:
compiler/xml_documentation.m:
    Conform to the change to file_names.m.

    Consistently use "Ext" for the abstract representation of extensions
    and "ExtStr" for their string representation.

    In a few places, add "XXX EXT" where the code manipulates extensions
    as strings in a way that potentially inferferes with the partition
    of extensions into classes.

    In a few places, rename predicates to avoid ambiguities. factor out
    common code, delete unneeded arguments, replace bools with bespoke types,
    and make similar minor improvements.

    In a few places, remove rafe-isms, such as the use ^elem.
2020-08-14 20:30:36 +10:00
Zoltan Somogyi
d4a175407e Add all pragmas in one pass.
compiler/hlds_module.m:
    Split the field containing foreign_decls into two: the decls added
    by the user, and the decls added by the compiler. The latter can refer
    to entities defined in the former, but not the reverse.

compiler/erl_code_gen.m:
compiler/export.m:
compiler/mercury_compile_llds_back_end.m:
compiler/ml_top_gen.m:
    Always put the foreign decls generated by the compiler *after* the ones
    written by the user. The other way around could cause the target language
    compiler to see a use of a type name before its definition.

compiler/add_mutable_aux_preds.m:
compiler/add_pragma.m:
    Add both user-provided and compiler-generated foreign decls to the
    relevant field of the HLDS.

compiler/make_hlds_passes.m:
    Document why we don't have to add any pragmas in the modern equivalent
    of the old pass 2 anymore. The separation of user and auxiliary foreign
    decls was the last issue tying us to that old scheme.

compiler/prog_foreign.m:
    Delete two type synonyms that are not really needed.
2019-11-27 00:12:10 +11:00
Zoltan Somogyi
ce65f6b2aa Fix more issues reported by --warn-inconsistent-pred-order-clauses.
compiler/assertion.m:
compiler/clause_to_proc.m:
compiler/compute_grade.m:
compiler/const_struct.m:
compiler/export.m:
compiler/hlds_dependency_graph.m:
compiler/hlds_out_mode.m:
compiler/hlds_promise.m:
compiler/lambda.m:
compiler/lp_rational.m:
compiler/make_goal.m:
compiler/mercury_compile_llds_back_end.m:
compiler/ml_type_gen.m:
compiler/name_mangle.m:
compiler/parse_tree_out_inst.m:
compiler/parse_tree_out_pragma.m:
compiler/parse_tree_to_term.m:
compiler/parse_type_name.m:
compiler/passes_aux.m:
compiler/polyhedron.m:
compiler/pred_table.m:
compiler/process_util.m:
compiler/prog_data.m:
compiler/prog_data_foreign.m:
compiler/prog_mutable.m:
compiler/rat.m:
compiler/recompilation.m:
compiler/source_file_map.m:
compiler/timestamp.m:
compiler/trace_params.m:
compiler/write_deps_file.m:
    As above.

compiler/Mercury.options:
    Don't pass --no-warn-inconsistent-pred-order-clauses for the above modules.
2019-08-23 20:54:27 +10:00
Zoltan Somogyi
86f563a94d Pack subword-sized arguments next to a remote sectag.
compiler/du_type_layout.m:
    If the --allow-packing-remote-sectag option is set, then try to pack
    an initial subsequence of subword-sized arguments next to remote sectags.

    To allow the polymorphism transformation to put the type_infos and/or
    typeclass_infos it adds to a function symbol's argument list at the
    *front* of that argument list, pack arguments next to remote sectags
    only in function symbols that won't have any such extra arguments
    added to them.

    Do not write all new code for the new optimization; instead, generalize
    the code that already does a very similar job for packing args next to
    local sectags.

    Delete the code we used to have that picked the packed representation
    over the base unpacked representation only if it reduced the
    "rounded-to-even" number of words. A case could be made for its usefulness,
    but in the presence of the new optimization the extra code complexity
    it requires is not worth it (in my opinion).

    Extend the code that informs users about possible argument order
    rearrangements that yield better packing to take packing next to sectags
    into account.

compiler/hlds_data.m:
    Provide a representation for cons_tags that use the new optimization.
    Instead of adding a new cons_tag, we do this by replacing several old
    cons_tags that all represent pointers to memory cells with a single
    cons_tag named remote_args_tag with an argument that selects among
    the old cons_tags being replaced, and adding a new alternative inside
    this new type. The new alternative is remote_args_shared with a
    remote_sectag whose size is rsectag_subword(...).

    Instead of representing the value of the "data" field in classes
    on the Java and C# backends as a strange kind of secondary tag
    that is added to a memory cell by a class constructor instead of
    having to be explicitly added to the front of the argument vector
    by the code of a unification, represent it more directly as separate
    kind of remote_args_tag. Continuing to treat it as a sectag would have
    been very confusing to readers of the code of ml_unify_gen_*.m in the
    presence of the new optimization.

    Replacing several cons_tags that were usually treated similarly with
    one cons_tag simplifies many switches. Instead of an switch with that
    branches to the same switch arm for single_functor_tag, unshared_tag
    and shared_remote_tag, and then switches on these three tags again
    to get e.g. the primary tag of each, the new code of the switch arm
    is executed for just cons_tag value (remote_args_tag), and switches
    on the various kinds of remote args tags only when it needs to.
    In is also more natural to pass around the argument of remote_args_tag
    than to pass around a variable of type cons_tag that can be bound to only
    single_functor_tag, unshared_tag or shared_remote_tag.

    Add an XXX about possible further steps along these lines, such as
    making a new cons_tag named something like "user_const_tag" represent
    all user-visible constants.

compiler/unify_gen_construct.m:
compiler/unify_gen_deconstruct.m:
compiler/unify_gen_test.m:
compiler/unify_gen_util.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:
    Implement X = f(Yi) unifications where f uses the new representation,
    i.e. some of its arguments are stored next to a remote sectag.

    Some of the Yi are stored in a tagword (a word that also contains a tag,
    in this case the remote secondary tag), while some are stored in other
    words in a memory cell. This means that such unifications have similarities
    both to unifications involving arguments being packed next to local
    sectags, and to unifications involving ordinary arguments in memory cells.
    Therefore wherever possible, their implemenation uses suitably generalized
    versions of existing code that did those two jobs for two separate kinds of
    cons_tags.

    Making such generalizations possible in some cases required shifting the
    boundary between predicates, moving work from a caller to a callee
    or vice versa.

    In unify_gen_deconstruct.m, stop using uni_vals to represent *either* a var
    *or* a word in a memory cell. While this enabled us to factor out some
    common code, the predicate boundaries it lead to are unsuitable for the
    generalizations we now need.

    Consistently use unsigned ints to represent both the whole and the parts
    of words containing packed arguments (and maybe sectags), except when
    comparing ptag constants with the result of applying the "tag" unop
    to a word, (since that unop returns an int, at least for now).

    In a few cases, avoid the recomputation of some information that we
    already know. The motivation is not efficiency, since the recomputation
    we avoid is usually cheap, but the simplification of the code's correctness
    argument.

    Use more consistent terminology in things such as variable names.

    Note the possibility of further future improvements in several places.

compiler/ml_foreign_proc_gen.m:
    Delete a long unused predicate.

compiler/mlds.m:
    Add an XXX documenting a possible improvement.

compiler/rtti.m:
    Update the compiler's internal representation of RTTI data structures
    to make them able to describe secondary tags that are smaller than
    a full word.

compiler/rtti_out.m:
    Conform to the changes above, and delete a long-unused predicate.

compiler/type_ctor_info.m:
    Use the RTTI's du_hl_rep to represent cons_tags that distinguish
    between function symbols using a field in a class.

compiler/ml_type_gen.m:
    Provide a specialized form of a function for code in ml_unify_gen_*.m.
    Conform to the changes above.

compiler/add_special_pred.m:
compiler/bytecode_gen.m:
compiler/export.m:
compiler/hlds_code_util.m:
compiler/lco.m:
compiler/ml_closure_gen.m:
compiler/ml_switch_gen.m:
compiler/ml_tag_switch.m:
compiler/rtti_to_mlds.m:
compiler/switch_util.m:
compiler/tag_switch.m:
    Conform to the changes above.

runtime/mercury_type_info.h:
    Update the runtime's representation of RTTI data structures to make them
    able to describe remote secondary tags that are smaller than a full word.

runtime/mercury_deconstruct.[ch]:
runtime/mercury_deconstruct.h:
runtime/mercury_deconstruct_macros.h:
runtime/mercury_ml_expand_body.h:
runtime/mercury_ml_arg_body.h:
runtime/mercury_ml_deconstruct_body.h:
runtime/mercury_ml_functor_body.h:
    These modules collectively implement the predicates in deconstruct.m
    in the library, and provide access to its functionality to other C code,
    e.g. in the debugger. Update these to be able to handle terms with the
    new data representation optimization.

    This update requires a significant change in the distribution of work
    between these files for the predicates deconstruct.deconstruct and
    deconstruct.limited_deconstruct. We used to have mercury_ml_expand_body.h
    fill in the fields of their expand_info structures (whose types are
    defined in mercury_deconstruct.h) with pointers to three vectors:
    (a) a vector of arg_locns with one element per argument, with a NULL
    pointer being equivalent to a vector with a given element in every slot;
    (b) a vector of type_infos with one element per argument, constructed
    dynamically (and later freed) if necessary; and (c) a vector of argument
    words. Once upon a time, before double-word and sub-word arguments,
    vector (c) also had one word per argument, but that hasn't been true
    for a while; we added vector (a) help the consumers of the expand_info
    decode the difference. The consumers of this info  always used these
    vectors to build up a Mercury term containing a list of univs,
    with one univ for each argument.

    This structure could be stretched to handle function symbols that store
    *all* their arguments in a tagword next to a local sectag, but I found
    that stretching it to cover function symbols that have *some* of their
    arguments packed next to a remote sectag and *some other* of their
    arguments in a memory cell as usual would have required a well-nigh
    incomprehensibly complex, and therefore almost undebuggable, interface
    between mercury_ml_expand_body.h and the other files above. This diff
    therefore changes the interface to have mercury_ml_expand_body.h
    build the list of univs directly. This make its code relatively simple
    and self-contained, and it should be somewhat faster then the old code
    as well, since it never needs to allocate, fill in and then free
    vectors of type_infos (each such typeinfo now gets put into a univ
    as soon as it is constructed). The downside is that if we ever wanted
    to get all the arguments at once for a purpose other than constructing
    a list of univs from them, it would nevertheless require constructing
    that list of univs anyway as an intermediate data structure. I don't see
    this downside is significant, because (a) I don't think such a use case
    is very likely, and (b) even if one arises, debuggable but a bit slow
    is probably preferable to faster but very hard to debug.

    Reduce the level of indentation of some of these files to make the code
    easier to edit. Do this by

    - not adding an indent level from switch statements to their cases; and
    - not adding an indent level when a case in a switch has a local block.

    Move the break or return ending a case inside that case's block,
    if it has one.

runtime/mercury_deep_copy_body.h:
runtime/mercury_table_type_body.h:
    Update these to enable the copying or tabling of terms whose
    representations uses the new optimization.

    Use the techniques listed above to reduce the level of indentation
    make the code easier to edit.

runtime/mercury_tabling.c:
runtime/mercury_term_size.c:
    Conform to the changes above.

runtime/mercury_unify_compare_body.h:
    Make this code compile after the changes above. It does need to work
    correctly, since we only ever used this code to compare the speed
    of unify-by-rtti with the speed of unify-by-compiler-generated-code,
    and in real life, we always use the latter. (It hasn't been updated
    to work right with previous arg packing changes either.)

library/construct.m:
    Update to enable the code to construct terms whose representations
    uses the new optimization.

    Add some sanity checks.

library/private_builtin.m:
runtime/mercury_dotnet.cs.in:
java/runtime/Sectag_Locn.java:
    Update the list of possible sectag kinds.

library/store.m:
    Conform to the changes above.

trace/mercury_trace_vars.c:
    Conform to the changes above.

tests/hard_coded/deconstruct_arg.{m,exp,exp2}:
    Extend this test to test the deconstruction of terms whose
    representations uses the new optimization.

    Modify some of the existing terms being tested to make them more diverse,
    in order to make the output easier to navigate.

tests/hard_coded/construct_packed.{m,exp}:
    A new test case to test the construction of terms whose
    representations uses the new optimization.

tests/debugger/browse_packed.{m,exp}:
    A new test case to test access to the fields of terms whose
    representations uses the new optimization.

tests/tabling/test_packed.{m,exp}:
    A new test case to test the tabling of terms whose
    representations uses the new optimization.

tests/debugger/Mmakefile:
tests/hard_coded/Mmakefile:
tests/tabling/Mmakefile:
    Enable the new test cases.
2018-08-30 05:14:38 +10:00
Peter Wang
a5da615a9d Don't use exceptions internally for foreign include file errors.
Use normal return values to signal errors internally if a file
referenced by an `include_file' in a foreign_decl or foreign_code
declaration is missing or there is some error reading from it,
instead of throwing and catching an exception. This allows a compiler
built in a deep profiling grade to continue without aborting.

compiler/file_util.m
    Make the closure argument to output_to_file return a list of error
    strings, and make output_to_file return a boolean indicating if
    there were any errors.

    Delete output_to_file_return_result as it was only used to implement
    output_to_file.

    Make write_include_file_contents and
    write_include_file_contents_cur_stream return an error instead of
    throwing an exception if the include file could not be opened or
    copied to the output stream.

    Delete the include_file_error type. Don't throw or catch exceptions
    of that type.

compiler/compiler_util.m:
    Add helper predicate maybe_is_error.

compiler/elds_to_erlang.m
compiler/llds_out_file.m
compiler/mlds_to_c_file.m
compiler/mlds_to_cs_file.m
compiler/mlds_to_java_file.m
    Return a list of errors when writing out target code or header
    files. Currently the only errors will be due to missing or
    unreadable foreign include files.

compiler/export.m
    Report errors due to missing or unreachable foreign include files.

    Delete the temporary .mh.tmp file if there was an error while
    generating it.
2018-08-18 10:38:54 +10:00
Zoltan Somogyi
cb4454ac28 Extend local arg packing to single-ctor types.
compiler/du_type_layout.m:
    For the last three weeks, we have been packing subword-sized arguments
    next to a local sectag (if the relevant option was set). However, we
    did this only for types with two or more function symbols. This diff
    extends this optimization to apply also to types with only one function
    symbol, whose representation is decided by a separate piece of code.

    Factor out a piece of code to be usable from both of those pieces of code.

    Delete a sanity test. By not failing for the last three weeks,
    it has done its job.

compiler/hlds_data.m:
    Replace the shared_local_tag_with_args cons_tag added in that change
    about three weeks ago with the local_args_tag cons_tag, which is more
    general, in that it can indicate whether the function symbol is the only
    one in its type or not. (We need to know this when generating code
    for deconstruction unifications.)

compiler/bytecode_gen.m:
compiler/export.m:
compiler/ml_switch_gen.m:
compiler/ml_type_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/switch_util.m:
compiler/type_ctor_info.m:
compiler/unify_gen_construct.m:
compiler/unify_gen_deconstruct.m:
compiler/unify_gen_test.m:
    Conform to the changes above.
2018-07-28 06:40:03 +10:00
Zoltan Somogyi
624aaa01f1 Pack subword-sized arguments next to a local sectag.
compiler/du_type_layout.m:
    If a new option is set, then try to represent function symbols with
    only subword-sized arguments by packing those arguments into the same word
    as the primary tag and (if it is needed) a secondary tag.

    If there are too many such function symbols for the available number of
    bits, pick the ones that need the least number of bits, in order to
    allow us to use this representation for as many such function symbols
    as possible.

    This diff implements this packing only for types that have more than one
    argument, because implementing it for types that have only one argument
    has two extra complications. One is the need for another new cons_id
    (see below), which would make this diff bigger and harder to review.
    The other is the need to consider interactions with the direct_arg
    optimization.

    Don't invoke the code for deciding the representation of arguments
    if either (a) the function symbol has no arguments, or (b) its cons_id
    alone dictates how we will treat its argument (in such cases, there is
    always exactly one).

    Fix a bug in computing the number of bits needed to distinguish N things.

    Store the value of the "experiment" option in the params for now,
    since it has helped track down bugs in this change, and may do the same
    for my next change. It costs next to nothing.

compiler/options.m:
    Add an option that controls whether we allow du_type_layout to pack
    arguments next to local secondary tags. The default value is "no",
    since "yes" may break binary compatibility.

    Add an option that controls whether we allow du_type_layout to pack
    arguments next to remote secondary tags. This option is not yet used.

compiler/hlds_data.m:
    Add a new cons_id, shared_local_tag_with_args, to represent function
    symbols in which the arguments are packed next to a local secondary tag.
    Rename the existing shared_local_tag cons_id as shared_local_tag_no_args,
    to clarify the distinction.

    Redesign the representation of secondary tags a bit, to meet the
    requirements I discovered while implementing the new data representation.

compiler/prog_data.m:
    Document the now-expanded uses of the arg_pos_width type.

compiler/ml_unify_gen.m:
compiler/unify_gen.m:
    Implement unifications involving the new cons_id.

compiler/var_locn.m:
    Implement deconstruction unifications involving both right-to-left data
    flow and the new cons_id for the LLDS backend requires var_locn.m
    to implement a new kind of assignment to a variable: one that updates
    its old value. Add a predicate for this. (Previously, deconstructions
    with right-to-left flow could update the old value of a word in a
    memory cell, whose state var_locn.m does *not* track.)

compiler/code_loc_dep.m:
    Provide the interface between unify_gen. and var_locn.m.

compiler/code_info.m:
    Store the number of primary tag bits in the code_info, to save it looking
    up in the globals structure, since with its new code, unify_gen.m needs it
    more often now.

compiler/hlds_out_module.m:
doc/user_guide.texi:
    Implement the capability of restricting the dump of the type table
    to only the types defined in the module being compiled. Without this,
    the type table is cluttered with information about types in other
    modules, including the automatically-included builtin modules.

compiler/handle_options.m:
    Add a new value of the -D option. The new value, du, asks for the
    dumping out of the representations of only the locally defined types.

compiler/ml_gen_info.m:
    Store the number of primary tag bits as a uint8, not as int.

compiler/ml_tag_switch.m:
compiler/switch_util.m:
compiler/tag_switch.m:
    Update the code that generates switches on du types to handle
    local secondary tags that must be masked off before use.

compiler/rtti.m:
    Update the compiler's representation of RTTI information to account for
    the new data representation.

compiler/type_ctor_info.m:
    Construct the updated RTTI representation.

compiler/bytecode_gen.m:
compiler/export.m:
compiler/ml_switch_gen.m:
compiler/ml_type_gen.m:
compiler/modecheck_goal.m:
compiler/rtti_out.m:
compiler/rtti_to_mlds.m:
    Conform for the changes above.

runtime/mercury_type_info.h:
    Extend the representation of du functors in the RTTI to account for
    the new data representation scheme. The extensions add only to the
    *ends* of structures, or to lists of enum values, with the extensions
    only being used if the representation is actually used, which should
    allow the updated runtime to also work with .c files that were compiled
    with a compiler that does *not* have this diff. For the same reason,
    make the old enum value MR_SECTAG_LOCAL a synonym for the new
    MR_SECTAG_LOCAL_REST_OF_WORD, which expresses a distinction that
    did not previously exist.

    Delete a reference to a file that no longer exists.

runtime/mercury_dotnet.cs.in:
library/rtti_implementation.m:
    Update the C# and Mercury mirrors of the types updated in
    mercury_type_info.h.

runtime/mercury_deconstruct.c:
runtime/mercury_deconstruct_macros.h:
runtime/mercury_ml_expand_body.h:
    Implement the deconstruction of terms using the new data representation.

runtime/mercury_deep_copy_body.h:
    Implement the copying of terms using the new data representation.

runtime/mercury_table_type_body.h:
    Implement the tabling of terms using the new data representation.

runtime/mercury_term_size.c:
    Implement computing the size of terms using the new data representation.

runtime/mercury_unify_compare_body.h:
    Implement RTTI-based unifications of terms using the new data
    representation. (Or at least make a first attempt at this implementation.
    We never use RTTI-based unification, so this code has not been tested,
    but it is not clear that it *needs* to be tested.)

library/construct.m:
    Implement the construction of terms using the new data representation.

library/private_builtin.m:
    List MR_SECTAG_LOCAL_REST_OF_WORD as a synonym of MR_SECTAG_LOCAL for Java,
    since rtti_to_mlds.m will now emit the new version.

    Note that the new data representation is not applicable to Java (or C#),
    so it should never see the other kind of sectag (MR_SECTAG_LOCAL_BITS).

tests/hard_coded/sectag_bits.{m,exp}:
tests/hard_coded/sectag_bits_test_data:
    A new test case to test the reading in and writing out (and therefore
    the construction and deconstruction) of terms containing arguments
    packed with a local sectag.

tests/hard_coded/Mmakefile:
    Enable the new test case.
2018-07-08 17:54:11 +02:00
Zoltan Somogyi
1c13290492 Store its ordinal number with each functor.
This will be needed by an upcoming change.

compiler/prog_data.m:
compiler/hlds_data.m:
    Add the new field to (respectively) the parse tree and the HLDS
    representations of constructors.

compiler/parse_type_defn.m:
    Fill in the new field when parsing function symbols in type definitions.

compiler/du_type_layout.m:
    Transmit the ordinal number from the parse tree representation of
    constructors to their HLDS representation.

    Add some predicates needed by that upcoming change.

compiler/add_special_pred.m:
compiler/add_type.m:
compiler/check_typeclass.m:
compiler/equiv_type.m:
compiler/equiv_type_hlds.m:
compiler/export.m:
compiler/hhf.m:
compiler/hlds_out_module.m:
compiler/inst_check.m:
compiler/intermod.m:
compiler/ml_type_gen.m:
compiler/mode_util.m:
compiler/module_qual.qualify_items.m:
compiler/parse_tree_out.m:
compiler/prog_type.m:
compiler/recompilation.check.m:
compiler/recompilation.usage.m:
compiler/resolve_unify_functor.m:
compiler/special_pred.m:
compiler/term_constr_build.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 above.
2018-06-08 02:58:00 +02:00
Zoltan Somogyi
b06b2621b3 Move towards packing args with secondary tags.
compiler/hlds_data.m:
    Add bespoke types to record information about local and remote secondary
    tags. The one for local secondary tags includes the value of the
    primary and secondary tag together, since construct unifications
    need to assign this value, and it is better to compute this once,
    instead leaving the target language compiler to do it, potentially
    many times.

    Use a wrapped uint8 to record primary tag values, and wrapped uints
    to record secondary tag values. The wrap is to prevent any accidental
    confusion with other values. The use of uint8 and uint has two purposes.
    First, using the tighest possible representation. Tags are never negative,
    and primary tags cannot exceed 7. Second, using these types in the compiler
    help us eat our own dogfood; if a change causes a problem affecting
    these types, its bootcheck should fail, alerting us to the problem.

    Add commented-out types and fields that will be needed for packing
    sub-word-sized arguments together with both local and remote secondary
    tags.

compiler/du_type_layout.m:
    Generate references to tags in the new format.

compiler/ml_unify_gen.m:
compiler/unify_gen.m:

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

    Fix an old bug: the inst corresponding to a constant with a primary
    and a local secondary tag is not the secondary tag alone, but both tags
    together.

compiler/bytecode.m:
compiler/bytecode_gen.m:
compiler/closure_gen.m:
compiler/disj_gen.m:
compiler/export.m:
compiler/hlds_code_util.m:
compiler/jumpopt.m:
compiler/lco.m:
compiler/llds_out_data.m:
compiler/llds_out_instr.m:
compiler/lookup_switch.m:
compiler/lookup_util.m:
compiler/ml_accurate_gc.m:
compiler/ml_call_gen.m:
compiler/ml_closure_gen.m:
compiler/ml_code_util.m:
compiler/ml_elim_nested.m:
compiler/ml_string_switch.m:
compiler/ml_switch_gen.m:
compiler/ml_tag_switch.m:
compiler/ml_type_gen.m:
compiler/mlds_dump.m:
compiler/mlds_to_c_data.m:
compiler/mlds_to_c_stmt.m:
compiler/opt_debug.m:
compiler/peephole.m:
compiler/rtti.m:
compiler/rtti_out.m:
compiler/rtti_to_mlds.m:
compiler/string_switch.m:
compiler/switch_util.m:
compiler/tag_switch.m:
compiler/type_ctor_info.m:
    Conform to the change to hlds_data.m.

    In two places, in rtti_out.m and rtti_to_mlds.m, delete old code
    that was needed only to implement reserved tags, which we have
    stopped supporting a few months ago.

library/uint8.m:
library/uint16.m:
library/uint32.m:
library/uint64.m:
    Add predicates to cast from each of these types to uint.
2018-06-06 03:35:20 +02:00
Zoltan Somogyi
fc903a0911 Eliminate the double storage of types in the MLDS.
compiler/mlds.m:
    When we record a Mercury type in the MLDS, we used to record with it
    not just its type category (which some aux predicates need), but also
    the name by which it is known to the target language compiler, if the
    type is defined in that foreign language. Unfortunaly, the data structure
    we used to represent the name of the foreign type (and any assertions
    on it) also stored a duplicate copy of the Mercury type in the usual
    case where the Mercury type was *not* defined in the foreign language.
    Having two copies of the same information was dangerous, due to the
    possibility of inconsistency between them. It was also unnecessary work
    for the compiler passes that had to create the duplicate copies.

    Eliminate these problems by always storing *one* copy of the Mercury type.

    Store the Mercury and foreign type information next to each other.

compiler/foreign.m:
    Make the above possible by deleting up the old exported_type type,
    which contained the duplicate copy of the Mercury type in usual case
    of a type that is not defined by foreign code, and replacing it
    with a type that contains information about just a foreign type.

    In the argument lists of the predicates and functions of this module,
    replace arguments that used to be type exported_type with a pair
    of the Mercury type and a maybe of the new type, which is yes(...)
    iff the Mercury type *is* defined in foreign code.

    Give some predicates and functions more meaningful names.

    Make specialized versions of these functions available (specialized
    e.g. to a target language) where these would be useful.

    Delete the auxiliary predicates that aren't needed with the
    new data structure design.

compiler/export.m:
compiler/ml_accurate_gc.m:
compiler/ml_code_util.m:
compiler/ml_foreign_proc_gen.m:
compiler/ml_global_data.m:
compiler/ml_simplify_switch.m:
compiler/ml_switch_gen.m:
compiler/ml_unify_gen.m:
compiler/mlds_to_c.m:
compiler/mlds_to_cs.m:
compiler/mlds_to_java.m:
compiler/rtti_to_mlds.m:
    Conform to the changes above.
2018-05-08 00:17:34 +02:00
Zoltan Somogyi
860f54cafd Make offset tracking work for C# (and Java).
My recent diff adding position information to the representation of constructor
arguments assumed that the remote secondary tag, if any, was always added
to the start of the memory cell by the compiler module handling unifications.
However, for the C# and Java grades, secondary tags are in fact added
by a class constructor, so the offsets of the arguments of such cells
were off by one, leading to an assertion failure in the compiler.

compiler/hlds_data.m:
    Fix the above problem by recording with each remote secondary tag
    whether it is added by the unify code or by the constructor.

compiler/du_type_layout.m:
    Set the new field in remote secondary tags.

compiler/ml_unify_gen.m:
compiler/unify_gen.m:
    Use the new field to decide whether a remote secondary tag counts
    as occupying the first word of its memory cell.

compiler/bytecode_gen.m:
compiler/export.m:
compiler/lco.m:
compiler/ml_switch_gen.m:
compiler/ml_type_gen.m:
compiler/switch_util.m:
compiler/type_ctor_info.m:
    Conform to the change in hlds_data.m.
2018-05-06 23:43:15 +02:00
Zoltan Somogyi
24b98fdafe Pack sub-word-sized ints and dummies in terms.
Previously, the only situation in which we could pack two or more arguments
of a term into a single word was when all those arguments are enums. This diff
changes that, so that the arguments can also be sub-word-sized integers
(signed or unsigned), or values of dummy types (which occupy zero bits).

This diff also records, for each argument of a function symbol, not just
whether, and if yes, how it is packed into a word, but also at *what offset*
that word is in the term's heap cell. It is more economical to compute this
once, when the representation of the type is being decided, than to compute
it over and over again when terms with that function symbol are being
constructed or deconstructed. However, for a transition period, we compute
these offsets at *both* times, to check the consistency of the new algorithm
for computing offsets that is run at "decide representation time" with
the old algorithms run at "generate code for a unification time".

compiler/du_type_layout.m:
    Make the changes described above: pack sub-word-sized integers and
    dummy values into argument words, if possible, and if the relevant
    new option allows it. These options are temporary. If we find no problems
    with the new packing algorithm in a few weeks, we should be able to
    delete them.

    Allow 64 bit ints and uints to be stored in unboxed in two words
    on 32 bit platforms, if the relevant new option allows it. Support
    for this is not yet complete, but it makes sense to implement the
    RTTI changes for both this change and one described in the above
    paragraph together.

    For each packed argument, record not just its width, its shift and
    the mask, but also the number of bits the argument takes. Previously,
    we computed this on demand from the mask, but there is no real need
    for that when simply storing this info is so cheap.

    For all arguments, packed or not, record its offset, relative to both
    the start of the arguments, and the start of the memory cell. (The two
    are different if the arguments are preceded by either a remote secondary
    tag, the typeinfos and/or typeclass_infos describing some existentially
    typed arguments, or both.) The reason for this is given at the top.

    Centralize the decision of the parameters of packing in one predicate.

    If the option --inform-suboptimal-packing is given, print an informational
    message whenever the code deciding type representations finds that
    reordering the arguments of a function symbol would allow it to pack
    the arguments of that function symbol into less space.

compiler/options.m:
    Add the option --allow-packing-ints which controls whether
    du_type_layout.m will attempt to pack {int,uint}{8,16,32} arguments
    alongside enum arguments.

    Add the option --allow-packing-dummies which controls whether
    du_type_layout.m will optimize away (in other words, represent in 0 bits)
    arguments of dummy types.

    Add the option --allow-double-word-ints which controls whether
    du_type_layout.m will store arguments of the types int64 and uint64
    unboxed in two words on 32 bit platforms, the way it currently stores
    double precision floats.

    All three those options are off by default, which preserves binary
    compatibility with existing code. However, the first two are ready
    to be switched on (the third is not).

    All three options are intended to be present in the compiler
    only until these changes are tested. Once we deem them sufficiently
    tested, I will modify the compiler to always do the packing they control,
    at which point we can delete these options. This is why they are not
    documented.

    Add the option --inform-suboptimal-packing, whose meaning is described
    above.

doc/user_guide.texi:
    Document --inform-suboptimal-packing.

compiler/prog_data.m:
    For each argument of a function symbol in a type definition, use
    a new type called arg_pos_width to record the extra information
    mentioned above in (offsets for all arguments, and number of bits
    for packed arguments).

    For each function symbol that has some existential type constraints,
    record the extra information mentioned for parse_type_defn.m below.

compiler/hlds_data.m:
    Include the position, as well as the width, in the representation
    of the arguments of function symbols.

    Previously, we used the integer 0 as a tag for dummies. Add a tag to
    represent dummy values, since this gives more information to any code
    that sees that tag.

compiler/ml_unify_gen.m:
compiler/unify_gen.m:
    Handle the packing of dummy values, and of sub-word-sized ints and uints.

    Compare the cell offset of each argument computed using existing
    algorithms here with the cell offset recorded in the argument's
    representation, and abort if they are different.

    In some cases, restructure code a bit to make it possible.
    For example, for tuples and closures, this means that instead of
    simply recording that each tuple argument or closure element
    is a full word, we must record its correct offset as well.

    Handle the new dummy_tag.

    Add prelim (not yet finished) support for double-word int64s/uint64s
    on 32 bit platforms.

    When packing the values of two or more variables (or constants) into a
    single word in a memory cell, optimize away operations that are no-ops,
    such as shifting anything by zero bits, shifting the constant zero
    by any number of bits, and ORing anything with zero. This makes the
    generated code easier to read. It is probably also faster for us
    to do it here than to write out a bigger expression, have the C compiler
    read in the bigger expression, and then later make the same optimization.

    In ml_unify_gen.m, avoid the unnecessary use of a list of the argument
    variables' types separate from the list of the argument variables
    themselves; just look up the type of each argument variable when it is
    processed.

compiler/add_special_pred.m:
    When creating special (unify and compare) predicates for tuples,
    include the offsets in the representation of their arguments.

    Delete an unused predicate.

compiler/llds.m:
    Add a new way to create an rval: a cast. We use it to implement
    the extraction of signed sub-word-sized integers from packed argument
    words in terms. Masking the right N bits out of the packed word
    leaves the other 32-N or 64-N bits as zeroes; a cast to int8_t,
    int16_t or int32_t will copy the sign bit to these bits.
    Likewise, when we pack signed int{8,16,32} values into words,
    we cast them to their unsigned versions to throw away any sign-extension
    bits in their original word-sized representations.

    No similar change is needed for the MLDS, since that already had
    a mechanism for casts.

compiler/mlds.m:
    Note a potential simplification in the MLDS.

compiler/builtin_lib_types.m:
    Add functions to return the Mercury representation of the int64
    and uint64 types.

compiler/foreign.m:
    Export a specialized version of an existing predicate, to allow
    ml_unify_gen.m to avoid the costs of the more general version.

compiler/hlds_out_module.m:
    Always print the representations of all arguments, since the
    inclusion of position information in those representation means that
    the representations of even all-full-word-argument terms are of potential
    interest when debugging term representations.

compiler/lco.m:
    Do not try to apply LCO to arguments of dummy types. (We could optimize
    them differently, by filling them in before they are "computed", but
    that is a separate optimization, which is of *very* low priority.)

compiler/liveness.m:
    Do not include variables of dummy types in resume points.

    The reason for this is that the code that establishes a resume point
    returns, for each such variable, a list of *lvals* where that variable
    can be found. The new code in unify_gen.m will optimize away assignments
    to values of dummy types, so there is *no* lval where they can be found.
    We could allocate one, but doing so would be a pessimization. Instead,
    we simply don't save and restore such values. When their value (which is
    always 0) is needed, we can create them out of thin air.

compiler/ml_global_data.m:
    Include the target language in the ml_global_data structure, to prevent
    some of its users having to look it up in the module_info.

    Add notes about the specializing the implementation of arrays of
    int64s/uint64s on 32 bit platforms.

compiler/check_typeclass.m:
compiler/ml_type_gen.m:
    Add sanity checks of the new precomputed fields of exist_constraints.

    Conform to the changes above.

compiler/mlds_to_c.m:
    Add prelim (not yet finished) support for double-word int64s/uint64s
    on 32 bit platforms.

    Add notes about possible optimizations.

compiler/parse_type_defn.m:
    When a function symbol in a type definition contains existential
    arguments, precompute and store the set of constrained and unconstrained
    type variables. The code in du_type_layout.m needs this information
    to compute the number of slots occupied by typeinfos and typeclass_infos
    in memory cells for this function symbol, and several other places
    in the compiler do too. It is easier and faster to compute this
    information just once, and this is the earliest time what that can be done.

compiler/type_ctor_info.m:
    Use the prerecorded information about existential types to simplify
    the code here

compiler/polymorphism.m:
    Add an XXX about possibly using the extra info we now record in
    exist_constraints to simplify the job of polymorphism.m.

compiler/pragma_c_gen.m:
compiler/var_locn.m:
    Create the values of dummy variables from scratch, if needed.

compiler/rtti.m:
    Replace a bool with a bespoke type.

compiler/rtti_out.m:
compiler/rtti_to_mlds.m:
    When generating RTTI information for the LLDS and MLDS backends
    respectively, record new kinds of arguments as needing special
    treatment. These are int64s and uint64s stored unboxed in two words
    on 32 bit platforms, {int,uint}{8,16,32} values packed into words,
    and dummy arguments. Each of these has a special code: its own negative
    negative value in the num_bits field of the argument.

    Generate slightly better formatted output.

compiler/type_util.m:
    Delete a predicate that isn't needed anymore.

compiler/opt_util.m:
    Delete a function that hasn't been needed for a while.

    Conform to the changes above.

compiler/arg_pack.m:
compiler/bytecode_gen.m:
compiler/call_gen.m:
compiler/code_util.m:
compiler/ctgc.selector.m:
compiler/dupelim.m:
compiler/dupproc.m:
compiler/equiv_type.m:
compiler/equiv_type_hlds.m:
compiler/erl_code_gen.m:
compiler/erl_rtti.m:
compiler/export.m:
compiler/exprn_aux.m:
compiler/global_data.m:
compiler/jumpopt.m:
compiler/livemap.m:
compiler/llds_out_data.m:
compiler/middle_rec.m:
compiler/ml_closure_gen.m:
compiler/ml_switch_gen.m:
compiler/ml_top_gen.m:
compiler/module_qual.qualify_items.m:
compiler/opt_debug.m:
compiler/parse_tree_out.m:
compiler/peephole.m:
compiler/recompilation.usage.m:
compiler/resolve_unify_functor.m:
compiler/stack_layout.m:
compiler/structure_reuse.direct.choose_reuse.m:
compiler/switch_util.m:
compiler/typecheck.m:
compiler/unify_proc.m:
compiler/unused_imports.m:
compiler/xml_documentation.m:
    Conform to the changes above.

compiler/llds_out_util.m:
    Add a comment.

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

runtime/mercury_type_info.h:
    Allocate special values of the MR_arg_bits field of the MR_DuArgLocn type
    to designate arguments as two word int64/uint64s, as sub-word-sized
    arguments of types {int,uint}{8,16,32}, or as arguments of dummy types.
    (We already had a special value for two word float arguments.)

    Document the list of places that know about this code, so that they
    can be updated if and when it changes.

library/construct.m:
    Handle the construction of terms with two-word int64/uint64 arguments,
    with packed {int,uint}{8,16,32} arguments, and with dummy arguments.

    Factor out the code common to the sectag-present and sectag-absent cases,
    to make it possible to do the above in just *one* place.

library/store.m:
    Add an XXX to a place that I don't think handles two word arguments
    correctly. (I think this is an old bug.)

runtime/mercury_deconstruct.c:
    Handle the deconstruction of terms with two-word int64/uint64 arguments,
    with packed {int,uint}{8,16,32} arguments, and with dummy arguments.

runtime/mercury_deep_copy_body.h:
    Handle the copying of terms with two-word int64/uint64 arguments,
    with packed {int,uint}{8,16,32} arguments, and with dummy arguments.

    Give a macro a more descriptive name.

runtime/mercury_type_info.c:
    Handle taking the size of terms with two-word int64/uint64 arguments,
    with packed {int,uint}{8,16,32} arguments, and with dummy arguments.

runtime/mercury.h:
    Put related definitions next to each other.

runtime/mercury_deconstruct.h:
runtime/mercury_ml_expand_body.h:
    Fix indentation.

tests/hard_coded/construct_test.{m,exp}:
    Add to this test case a test of the construction, via the library's
    construct.m module, of terms containing packed sub-word-sized integers,
    and packed dummies.

tests/hard_coded/deconstruct_arg.{m,exp}:
    Convert the source code of this test case to state variable notation,
    and update the line number references (in the names of predicates created
    from lambda expressions) accordingly.

tests/hard_coded/uint64_ground_term.{m,exp}:
    A new test case to check that uint64 values too large to be int64 values
    can be stored in static structures.

tests/hard_coded/Mmakefile:
    Enable the new test case.
2018-05-05 13:22:19 +02:00
Zoltan Somogyi
955a69efff Give better names to some functions.
compiler/type_util.m:
    Rename the "check_dummy_type" function to "is_type_a_dummy", since this
    expresses its job more clearly.

    Make the implementation of "is_type_a_dummy" slightly more efficient,
    by avoiding some redundant actions.

    Provide a new function "is_either_type_a_dummy" that does
    what its name says, and which is somewhat more efficient than
    two separate calls to "is_type_a_dummy".

compiler/prog_type.m:
    Rename the "check_builtin_dummy_type_ctor" function to
    "is_type_ctor_a_builtin_dummy", since this expresses its job
    more clearly.

compiler/ml_unify_gen.m:
    Conform to the name changes.

    Use the new function where relevant to simplify some code.

    Fix some comments.

compiler/code_info.m:
compiler/code_loc_dep.m:
compiler/continuation_info.m:
compiler/erl_call_gen.m:
compiler/erl_code_gen.m:
compiler/erl_code_util.m:
compiler/erl_unify_gen.m:
compiler/export.m:
compiler/higher_order.m:
compiler/hlds_pred.m:
compiler/live_vars.m:
compiler/llds_out_instr.m:
compiler/mark_tail_calls.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_foreign_proc_gen.m:
compiler/pragma_c_gen.m:
compiler/stack_layout.m:
compiler/term_constr_util.m:
compiler/trace_gen.m:
compiler/unify_gen.m:
compiler/unify_proc.m:
compiler/var_locn.m:
compiler/write_module_interface_files.m:
    Use the new function where relevant.
2018-02-28 13:48:44 +11:00
Zoltan Somogyi
f4bd666ec6 Simplify the handling of foreign_export_enums.
compiler/hlds_module.m:
    Change the representation of the mapping from Mercury constants
    to their exported foreign names from being a sym_name->string map
    to being a plain string->string map. Several parts of the compiler
    already required the sym_name key to be unqualified, which meant
    that its information content was just the constant's name anyway.
    This change enforces that invariant by encoding it in the data type.

    Document the fields of exported_enum_info. Put those fields into
    an order that makes this documentation flow logically.

compiler/add_foreign_enum.m:
    Rationalize the way foreign_export_enums (FEEs) are processed and checked.
    Check each entry in the override map just once, when it is first processed,
    and string away its module qualification then (after checking it).
    (Leaving the qualification check until later was probably the reason
    for the choice of a sym_name->string map in the old version.)

    Check whether the override map deviates from a bijection by keeping track
    of which Mercury constant names and which foreign names we have seen so
    far. This allows the error messages about "not a bijection" to say *why*
    the mapping is not a bijection. It also fixes an old bug that generated
    a "not a bijection" error for override maps that *were* bijections,
    but were bijections that covered only *some* of the enum type's constants.

    In error messages that include lists of constants or foreign names,
    consistently precede those lists with nl_indent_delta(2).

    Use a more consistent variable naming scheme.

compiler/export.m:
compiler/ml_type_gen.m:
    Conform to the changes in hlds_module.m.

tests/invalid/ee_invalid.err_exp:
tests/invalid/exported_foreign_enum.err_exp:
    Include the updated error messages in these expected outputs.

    Don't expect *any* error message for the FEE on line 75 of ee_invalid.m,
    which has a bijective (though incomplete) override map.
2018-02-24 13:50:52 +11:00
Zoltan Somogyi
dfe108251a Simplify the representation of foreign_export_enums.
compiler/hlds_module.m:
    The backends need to know how each constant in an enum type
    is represented if that type has a foreign_export_enum pragma.
    Transmit that information to them using the ctor_repns of the constants,
    so that they don't have to recreate it from the name of the constant
    and the cons_id_to_tag_map.

compiler/ml_type_gen.m:
    Conform to the change in hlds_module.m.

    Factor out a switch converting enums' tags to rvals that was duplicated
    in two places.

compiler/export.m:
    Conform to the change in hlds_module.m.

    Include the foreign name of an enum constant with its representation;
    this simplifies the code.

compiler/add_foreign_enum.m:
    Conform to the change in hlds_module.m.

compiler/mlds.m:
    Document the reason why the MLDS representation of exported enums
    needs to know the type constructor.
2018-02-21 20:15:47 +11:00
Zoltan Somogyi
4b98f58d9d Don't use reserved addresses to represent functors.
Late last year, we agreed to delete the ability to use the addresses
of reserved objects as cons_tags. After another (very short) discussion
on m-dev, this diff also deletes the ability to use small integers
(including zero) acting as pointers.

compiler/options.m:
    Delete the --num-reserved-addresses option.

    Add a synomym for --compiler-sufficiently-recent, with the intention
    that support for the representation of reserved addresses in RTTI
    code in the runtime will be deleted when all installed compilers
    have this new synonym.

compiler/hlds_data.m:
    Delete any mention of the reserved addresses from the cons_tag type,
    since we don't have reserved addresses anymore.

    Don't record for each type whether it uses reserved addresses;
    no type can do so anymore.

compiler/rtti.m:
    Delete the part of the RTTI representation that dealt with reserved
    addresses.

compiler/add_foreign_enum.m:
compiler/add_special_pred.m:
compiler/bytecode_gen.m:
compiler/code_info.m:
compiler/du_type_layout.m:
compiler/equiv_type_hlds.m:
compiler/erl_rtti.m:
compiler/export.m:
compiler/hlds_out_module.m:
compiler/intermod.m:
compiler/ml_switch_gen.m:
compiler/ml_type_gen.m:
compiler/ml_unify_gen.m:
compiler/ml_util.m:
compiler/opt_debug.m:
compiler/prog_data.m:
compiler/rtti_out.m:
compiler/rtti_to_mlds.m:
compiler/structure_reuse.direct.choose_reuse.m:
compiler/switch_gen.m:
compiler/switch_util.m:
compiler/type_ctor_info.m:
compiler/type_util.m:
compiler/unify_gen.m:
    Conform to the changes above, mostly by deleting code that used to deal
    with reserved addresses.
2018-02-06 16:03:44 +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
Julien Fischer
f519e26173 Add builtin 64-bit integer types -- Part 1.
Add the new builtin types: int64 and uint64.

Support for these new types will need to be bootstrapped over several changes.
This is the first such change and does the following:

- Extends the compiler to recognise 'int64' and 'uint64' as builtin types.
- Extends the set of builtin arithmetic, bitwise and relational operators
  to cover the new types.
- Adds the new internal option '--unboxed-int64s' to the compiler; this will be
  used to control whether 64-bit integer types are boxed or not.
- Extends all of the code generators to handle the new types.
- Extends the runtimes to support the new types.
- Adds new modules to the standard library intend to contain basic operations
  on the new types.  (These are currently empty and not documented.)

There are bunch of limitations marks with "XXX INT64"; these will be lifted in
part 2 of this change.  Also, 64-bit integer types are currently always boxed,
again this limitation will be lifted in later changes.

compiler/options.m:
    Add the new option --unboxed-int64s.

compiler/prog_type.m:
compiler/prog_data.m:
compiler/builtin_lib_types.m:
     Recognise int64 and uint64 as builtin types.

compiler/builtin_ops.m:
     Add builtin operations for the new types.

compiler/hlds_data.m:
     Add new tag types for the new types.

compiler/ctgc.selector.m:
compiler/dead_proc_elim.m:
compiler/export.m:
compiler/foreign.m:
compiler/goal_util.m:
compiler/higher_order.m:
compiler/hlds_code_util.m:
compiler/hlds_dependency_graph.m:
compiler/hlds_out_pred.m:
compiler/hlds_out_util.m:
compiler/implementation_defined_literals.m:
compiler/inst_check.m:
compiler/mercury_to_mercury.m:
compiler/mode_util.m:
compiler/module_qual.qualify_items.m:
compiler/opt_debug.m:
compiler/opt_util.m:
compiler/parse_tree_to_term.m:
compiler/parse_type_name.m:
compiler/polymorphism.m:
compiler/prog_out.m:
compiler/prog_util.m:
compiler/rbmm.execution_path.m:
compiler/rtti.m:
compiler/table_gen.m:
compiler/type_util.m:
compiler/typecheck.m:
compiler/unify_gen.m:
compiler/unify_proc.m:
compiler/unused_imports.m:
compiler/xml_documentation.m:
    Conform to the above changes to the parse tree and HLDS.

compiler/c_util.m:
    Support writing out constants of the new types.

compiler/llds.m:
    Add a representation for constants of the new types to the LLDS.

compiler/stack_layout.m:
    Add a new field to the stack layout params that records whether
    64-bit integers are boxed or not.

compiler/call_gen.:m
compiler/code_info.m:
compiler/disj_gen.m:
compiler/dupproc.m:
compiler/exprn_aux.m:
compiler/global_data.m:
compiler/jumpopt.m:
compiler/llds_out_data.m:
compiler/llds_out_instr.m:
compiler/lookup_switch.m:
compiler/mercury_compile_llds_back_end.m:
compiler/prog_rep.m:
compiler/prog_rep_tables.m:
compiler/var_locn.m b/compiler/var_locn.m:
    Support the new types in the LLDS code generator.

compiler/mlds.m:
    Support constants of the new types in the MLDS.

compiler/ml_call_gen.m:
compiler/ml_code_util.m:
compiler/ml_global_data.m:
compiler/ml_rename_classes.m:
compiler/ml_top_gen.m:
compiler/ml_type_gen.m:
compiler/ml_unify_gen.m:
compiler/ml_util.m:
compiler/mlds_to_target_util.m:
compiler/rtti_to_mlds.m:
     Conform to the above changes to the MLDS.

compiler/mlds_to_c.m:
compiler/mlds_to_cs.m:
compiler/mlds_to_java.m:
    Generate the appropriate target code for constants of the new types
    and operations involving them.

compiler/bytecode.m:
compiler/bytecode_gen.m:
    Handle the new types in the bytecode generator; we just abort if we
    encounter them for now.

compiler/elds.m:
compiler/elds_to_erlang.m:
compiler/erl_call_gen.m:
compiler/erl_code_util.m:
compiler/erl_unify_gen.m:
    Handle the new types in the Erlang code generator.

library/private_builtin.m:
    Add placeholders for the builtin unify and compare operations for
    the new types.  Since the bootstrapping compiler will not recognise
    the new types we give them polymorphic arguments.  These can be
    replaced after this change has bootstrapped.

    Update the Java list of TypeCtorRep constants here.

library/int64.m:
library/uint64.m:
    New modules that will eventually contain builtin operations on the new
    types.

library/library.m:
library/MODULES_UNDOC:
    Do not include the above modules in the library documentation for now.

library/construct.m:
library/erlang_rtti_implementation.m:
library/rtti_implementation.m:
library/table_statistics.m:
deep_profiler/program_representation_utils.m:
mdbcomp/program_representation.m:
    Handle the new types.

configure.ac:
runtime/mercury_conf.h.in:
    Define the macro MR_BOXED_INT64S.  For now it is always defined, support for
    unboxed 64-bit integers will be enabled in a later change.

runtime/mercury_dotnet.cs.in:
java/runtime/TypeCtorRep.java:
runtime/mercury_type_info.h:
    Update the list of type_ctor reps.

runtime/mercury.h:
runtime/mercury_int.[ch]:
    Add macros for int64 / uint64 -> MR_Word conversion, boxing and
    unboxing.

    Add functions for hashing 64-bit integer types suitable for use
    with the tabling mechanism.

runtime/mercury_tabling.[ch]:
    Add additional HashTableSlot structs for 64-bit integer types.

    Omit the '%' character from the conversion specifiers we pass via
    the 'key_format' argument to the macros that generate the table lookup
    function.  This is so we can use the C99 exact size integer conversion
    specifiers (e.g. PRIu64 etc.) directly here.

runtime/mercury_hash_lookup_or_add_body.h:
    Add the '%' character that was omitted above to the call to debug_key_msg.

runtime/mercury_memory.h:
     Add new builtin allocation sites for boxed 64-bit integer types.

runtime/mercury_builtin_types.[ch]:
runtime/mercury_builitn_types_proc_layouts.h:
runtime/mercury_construct.c:
runtime/mercury_deconstruct.c:
runtime/mercury_deep_copy_body.h:
runtime/mercury_ml_expand_body.h:
runtime/mercury_table_type_body.h:
runtime/mercury_tabling_macros.h:
runtime/mercury_tabling_preds.h:
runtime/mercury_term_size.c:
runtime/mercury_unify_compare_body.h:
    Add the new builtin types and handle them throughout the runtime.

runtime/Mmakefile:
    Add mercury_int.c to the list of .c files.

doc/reference_manual.texi:
     Add the new types to the list of reserved type names.

     Add the mapping from the new types to their target language types.
     These are commented out for now.
2018-01-12 09:29:24 -05:00
Julien Fischer
7c42aa1aa2 Use a separate type to describe integer tags.
compiler/hlds_data.m
     Use a separate type to describe integer tags and parameterise
     the int_tag functor of the cons_tag/0 type by that new type.

compiler/bytecode_gen.m:
compiler/dense_switch.m:
compiler/du_type_layout.m:
compiler/export.m:
compiler/hlds_code_util.m:
compiler/make_tags.m:
compiler/ml_type_gen.m:
compiler/ml_switch_gen.m:
compiler/ml_unify_gen.m:
compiler/switch_gen.m:
compiler/switch_util.m:
compiler/type_ctor_info.m:
compiler/unify_gen.m:
     Conform to the above change.

compiler/ml_code_util.m:
    Add a utility function for use by the above.
2017-07-23 12:05:57 +10:00
Julien Fischer
8a240ba3f0 Add builtin 8, 16 and 32 bit integer types -- Part 1.
Add the new builtin types: int8, uint8, int16, uint16, int32 and uint32.
Support for these new types will need to be bootstrapped over several changes.
This is the first such change and does the following:

- Extends the compiler to recognise 'int8', 'uint8', 'int16', 'uint16', 'int32'
  and 'uint32' as builtin types.
- Extends the set of builtin arithmetic, bitwise and relational operators to
  cover the new types.
- Extends all of the code generators to handle new types.  There currently lots
  of limitations and placeholders marked by 'XXX FIXED SIZE INT'.  These will
  be lifted in later changes.
- Extends the runtimes to support the new types.
- Adds new modules to the standard library intended to hold the basic
  operations on the new types.  (These are currently empty and not documented.)

This change does not introduce the two 64-bit types, 'int64' and 'uint64'.
Their implementation is more complicated and is best left to a separate change.

compiler/prog_type.m:
compiler/prog_data.m:
compiler/builtin_lib_types.m:
    Recognise int8, uint8, int16, uint16, int32 and uint32 as builtin types.

    Add new type, int_type/0,that enumerates all the possible integer types.

    Extend the cons_id/0 type to cover the new types.

compiler/builtin_ops.m:
    Parameterize the integer operations in the unary_op/0 and binary_op/0
    types by the new int_type/0 type.

    Add builtin operations for all the new types.

compiler/hlds_data.m:
    Add new tag types for the new types.

compiler/hlds_pred.m:
    Parameterize integers in the table_trie_step/0 type.

compiler/ctgc.selector.m:
compiler/dead_proc_elim.m:
compiler/export.m:
compiler/foreign.m:
compiler/goal_util.m:
compiler/higher_order.m:
compiler/hlds_code_util.m:
compiler/hlds_dependency_graph.m:
compiler/hlds_out_pred.m:
compiler/hlds_out_util.m:
compiler/implementation_defined_literals.m:
compiler/inst_check.m:
compiler/mercury_to_mercury.m:
compiler/mode_util.m:
compiler/module_qual.qualify_items.m:
compiler/opt_debug.m:
compiler/opt_util.m:
compiler/parse_tree_out_info.m:
compiler/parse_tree_to_term.m:
compiler/parse_type_name.m:
compiler/polymorphism.m:
compiler/prog_out.m:
compiler/prog_rep.m:
compiler/prog_rep_tables.m:
compiler/prog_util.m:
compiler/rbmm.exection_path.m:
compiler/rtti.m:
compiler/rtti_to_mlds.m:
compiler/switch_util.m:
compiler/table_gen.m:
compiler/type_constraints.m:
compiler/type_ctor_info.m:
compiler/type_util.m:
compiler/typecheck.m:
compiler/unify_gen.m:
compiler/unify_proc.m:
compiler/unused_imports.m:
compiler/xml_documentation.m:
    Conform to the above changes to the parse tree and HLDS.

compiler/c_util.m:
    Support generating the builtin operations for the new types.

doc/reference_manual.texi:
    Add the new types to the list of reserved type names.

    Add the mapping from the new types to their target language types.
    These are commented out for now.

compiler/llds.m:
    Replace the lt_integer/0 and lt_unsigned functors of the llds_type/0,
    with a single lt_int/1 functor that is parameterized by the int_type/0
    type.

    Add a representations for constants of the new types to the LLDS.

compiler/call_gen.m:
compiler/dupproc.m:
compiler/exprn_aux.m:
compiler/global_data.m:
compiler/jumpopt.m:
compiler/llds_out_data.m:
compiler/llds_out_global.m:
compiler/llds_out_instr.m:
compiler/lookup_switch.m:
compiler/middle_rec.m:
compiler/peephole.m:
compiler/pragma_c_gen.m:
compiler/stack_layout.m:
compiler/string_switch.m:
compiler/switch_gen.m:
compiler/tag_switch.m:
compiler/trace_gen.m:
compiler/transform_llds.m:
    Support the new types in the LLDS code generator.

compiler/mlds.m:
    Support constants of the new types in the MLDS.

compiler/ml_accurate_gc.m:
compiler/ml_call_gen.m:
compiler/ml_code_util.m:
compiler/ml_disj_gen.m:
compiler/ml_foreign_proc_gen.m:
compiler/ml_global_data.m:
compiler/ml_lookup_switch.m:
compiler/ml_simplify_switch.m:
compiler/ml_string_switch.m:
compiler/ml_switch_gen.m:
compiler/ml_tailcall.m:
compiler/ml_type_gen.m:
compiler/ml_unify_gen.m:
compiler/ml_util.m:
compiler/mlds_to_target_util.m:
    Conform to the above changes to the MLDS.

compiler/mlds_to_c.m:
compiler/mlds_to_cs.m:
compiler/mlds_to_java.m:
    Generate the appropriate target code for constants of the new
    types and operations involving them.

compiler/bytecode.m:
compiler/bytecode_gen.m:
    Handle the new types in the bytecode generator; we just abort if we
    encounter them for now.

compiler/elds.m:
compiler/elds_to_erlang.m:
compiler/erl_call_gen.m:
compiler/erl_code_util.m:
compiler/erl_rtti.m:
compiler/erl_unify_gen.m:
    Handle the new types in the Erlang code generator.

library/private_builtin.m:
    Add placeholders for the builtin unify and compare operations for
    the new types.  Since the bootstrapping compiler will not recognise
    the new types we give the polymorphic arguments.  These can be
    replaced after this change has bootstrapped.

    Update the Java list of TypeCtorRep constants.

library/int8.m:
library/int16.m:
library/int32.m:
library/uint8.m:
library/uint16.m:
library/uint32.m:
    New modules that will eventually contain builtin operations
    on the new types.

library/library.m:
library/MODULES_UNDOC:
    Do not include the above modules in the library documentation
    for now.

library/construct.m:
library/erlang_rtti_implementation.m:
library/rtti_implementation.m:
deep_profiler/program_representation_utils.m:
mdbcomp/program_representation.m:
    Handle the new types.

runtime/mercury_dotnet.cs.in:
java/runtime/TypeCtorRep.java:
runtime/mercury_type_info.h:
    Update the list of TypeCtorReps.

configure.ac:
runtime/mercury_conf.h.in:
    Check for the header stdint.h.

runtime/mercury_std.h:
    Include stdint.h; abort if that header is no present.

runtime/mercury_builtin_types.[ch]:
runtime/mercury_builtin_types_proc_layouts.h:
runtime/mercury_construct.c:
runtime/mercury_deconstruct.c:
runtime/mercury_deep_copy_body.h:
runtime/mercury_ml_expand_body.h
runtime/mercury_table_type_body.h:
runtime/mercury_tabling_macros.h:
runtime/mercury_tabling_preds.h:
runtime/mercury_term_size.c:
runtime/mercury_unify_compare_body.h:
    Add the new builtin types and handle them throughout the runtime.
2017-07-18 01:31:01 +10:00
Zoltan Somogyi
825bd11786 Fix bug in my previous change. 2017-06-16 14:07:59 +02:00
Zoltan Somogyi
c45d34a837 Use explicit streams in several modules.
compiler/export.m:
compiler/hlds_dependency_graph.m:
compiler/hlds_goal.m:
compiler/hlds_out_goal.m:
compiler/switch_util.m:
    As above.
2017-06-16 12:40:45 +02:00
Zoltan Somogyi
1af5bcf2f1 Make module_name_to_file_name currying-friendly.
compiler/file_names.m:
    Change the order of arguments of module_name_to_file_name and related
    predicates to make it easier to construct closures from them. Delete
    the previous higher-order-friendly versions, which the previous step
    has made unnecessary.

compiler/compile_target_code.m:
compiler/elds_to_erlang.m:
compiler/export.m:
compiler/find_module.m:
compiler/generate_dep_d_files.m:
compiler/intermod.m:
compiler/llds_out_file.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/mercury_compile_front_end.m:
compiler/mercury_compile_llds_back_end.m:
compiler/mercury_compile_main.m:
compiler/mercury_compile_middle_passes.m:
compiler/mercury_compile_mlds_back_end.m:
compiler/mlds_to_c.m:
compiler/mlds_to_cs.m:
compiler/mlds_to_java.m:
compiler/mmc_analysis.m:
compiler/mode_constraints.m:
compiler/module_cmds.m:
compiler/modules.m:
compiler/read_modules.m:
compiler/recompilation.check.m:
compiler/recompilation.usage.m:
compiler/write_deps_file.m:
compiler/write_module_interface_files.m:
compiler/xml_documentation.m:
    Conform to the change above. In several places, this means replacing
    explicit lambda expressions with simple partial application of the
    relevant predicates.
2017-06-12 19:38:20 +02:00
Zoltan Somogyi
61d0c67243 Improve diagnostics for foreign_{export_,}enum pragmas.
We can now generate error messages for types that have both foreign_enum
and reserve_tag pragmas, which we couldn't before. (In some cases,
we used to get a compiler abort.)

compiler/add_foreign_enum.m:
    Don't stop after finding the first problem with a foreign_export_enum
    or foreign_enum pragma; if a pragma has more than one problem,
    generate reports for them all.

    When reporting that the type named in a foreign_export_enum or
    foreign_enum is not an enum type, have the error message say *why*.

    Fill in the two new fields in exported_enum_infos (see below).

compiler/make_hlds_passes.m:
    Add reserve_tag pragmas to the HLDS before adding foreign_export_enum
    and foreign_enum pragmas. Since such a pragma would convert an enum
    type into a non-enum type, this is needed to ensure that the code
    in add_foreign_enum.m that checks whether a type is an enum type
    is operating on data that is final. Without that, it may make
    wrong decisions.

compiler/make_hlds_separate_items.m:
compiler/add_pragma.m:
    Provide the support needed by the new code in make_hlds_passes.m.

    In add_pragma.m, rename some insts to avoid name ambiguities,
    and simplify an if-then-else.

compiler/hlds_module.m:
    Add two fields to exported_enum_infos, to make processing them easier.
    (We couldn't do this earlier, since add_foreign_enum.m didn't have
    access to the final forms of the bodies of du type definitions,
    which is where the values of the two new fields come from.)

compiler/export.m:
compiler/ml_type_gen.m:
    Simplify some code using the new fields in exported_enum_infos.

compiler/error_util.m:
    Provide a mechanism to control whether sym_names in cons_ids
    are module qualified or not. This is "needed" by the new error
    messages created in add_foreign_enum.m.

compiler/check_promise.m:
compiler/det_report.m:
compiler/parse_inst_mode_name.m:
compiler/typecheck_errors.m:
    Conform to the change to error_util.m.

compiler/make_tags.m:
    Clean up some code and some comments.

tests/invalid/exported_foreign_enum.{m,err_exp}:
    A new test case to test the new capability to print more than one
    error message for the same pragma.

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

tests/invalid/ee_invalid.err_exp:
    Expect improved error messages.
2017-06-05 12:34:58 +02:00
Julien Fischer
092e175f45 Add a builtin unsigned word sized integer type -- Part 1.
Add a new builtin type: uint, which is an unsigned word sized integer type.
Support for this new type will need be bootstrapped over several changes.
This is the first such change and does the following:

- Extends the compiler to recognize 'uint' as a builtin type.
- Extends the set of builtin operations to include relational and (some)
  arithmetic operations on uints.
- Extends all of the code generators to handle the above.  There are some
  limitations currently marked by 'XXX UINT'.  These will be lifted once
  the compiler recognised uint and additional library support becomes
  available.
- Extends the runtime to support uints.

compiler/prog_type.m:
compiler/prog_data.m:
compiler/builtin_lib_types.m:
    Recognize uint as a builtin type.

    Add a new alternative to the cons_id/0 type corresponding to the uint type
    -- for bootstrapping purposes its argument is currently an int.

compiler/builtin_ops.m:
    Add builtin relational and arithmetic operations on uints.  Note that the
    existing 'unsigned_le' operation is actually intended for use with signed
    values.  Rather than attempt to modify its meaning, I have just added new
    operations specific to the uint type.

compiler/hlds_data.m:
    Add a new tag type for uints.

compiler/type_ctor_info.m:
    Recognise uint as a builtin.

    Bump the RTTI version number here.

compiler/ctgc.selector.m:
compiler/dead_proc_elim.m:
compiler/dependency_graph.m:
compiler/export.m:
compiler/foreign.m:
compiler/goal_util.m:
compiler/higher_order.m:
compiler/hlds_code_util.m:
compiler/hlds_out_pred.m:
compiler/hlds_out_util.m:
compiler/hlds_pred.m:
compiler/implementation_defined_literals.m:
compiler/inst_check.m:
compiler/mercury_to_mercury.m:
compiler/mode_util.m:
compiler/module_qual.qualify_items.m:
compiler/parse_tree_to_term.m:
compiler/parse_type_name.m:
compiler/polymorphism.m:
compiler/prog_out.m:
compiler/prog_rep.m:
compiler/prog_rep_tables.m:
compiler/prog_util.m:
compiler/rbmm.execution_path.m:
compiler/rtti.m:
compiler/special_pred.m:
compiler/switch_gen.m:
compiler/switch_util.m:
compiler/table_gen.m:
compiler/type_constraints.m:
compiler/type_util.m:
compiler/typecheck.m:
compiler/unify_gen.m:
compiler/unify_proc.m:
compiler/unused_imports.m:
compiler/write_module_interface_files.m:
compiler/xml_documentation.m:
    Conform to the above changes to the parse tree and HLDS.

compiler/c_util.m:
    Support generating builtin operations for uints.

compiler/llds.m:
    Add a representation for uint constants to the LLDS.

    Map uints onto MR_Unsigned.

compiler/call_gen.m:
compiler/dupproc.m:
compiler/exprn_aux.m:
compiler/global_data.m:
compiler/jumpopt.m:
compiler/llds_out_data.m:
compiler/llds_out_instr.m:
compiler/opt_debug.m:
compiler/opt_util.m:
    Support uints in the LLDS code generator.

compiler/mlds.m:
     Support uint constants in the MLDS.

compiler/ml_accurate_gc.m:
compiler/ml_call_gen.m:
compiler/ml_global_data.m:
compiler/ml_simplify_switch.m:
compiler/ml_switch_gen.m:
compiler/ml_tailcall.m:
compiler/ml_type_gen.m:
compiler/ml_unify_gen.m:
compiler/ml_util.m:
compiler/rtti_to_mlds.m:
    Conform to the above change to the MLDS.

compiler/mlds_to_c.m:
compiler/mlds_to_java.m:
compiler/mlds_to_cs.m:
     Generate the appropriate target code for uint constants and uint
     relational operations.

compiler/bytecode.m:
compiler/bytecode_gen.m:
     Handle uints in the bytecode generator: we just abort if we
     encounter them for now.

compiler/elds.m:
compiler/elds_to_erlang.m:
compiler/erl_call_gen.m:
compiler/erl_code_util.m:
compiler/erl_rtti.m:
compiler/erl_unify_gen.m:
    Handle uints in the Erlang code generator.

library/private_builtin.m:
    Add placeholders for builtin_{unify,compare}_uint.  Since the
    bootstrapping compiler will not recognize uint as a type, we
    give them polymorphic arguments.  These can be replaced after
    this change has bootstrapped.

    Update the Java list of TypeCtorRep constants, which for some
    reason is defined here.

library/uint.m:
    New module that will eventually contain operations on uints.

library/MODULES_DOCS:
library/library.m:
     Add the uint module.

library/construct.m:
library/erlang_rtti_implementation.m:
library/rtti_implementation.m:
mdbcomp/program_representation.m:
     Handle uints.

deep_profiler/program_representation_utils.m:
     Conform to the above change.

runtime/mercury_dotnet.cs.in:
     Update the list of TypeCtorReps for C#

java/runtime/TypeCtorRep.java:
     Update this, although the actual TypeCtorRep constants
     are defined the library.

runtime/mercury_type_info.h:
    Bump the RTTI version number.

    Add an alternative for uints to the tyepctor rep enum.

runtime/mercury_builtin_types.{h,c}:
runtime/mercury_builtin_types_proc_layouts.h:
runtime/mercury_deconstruct.c:
runtime/mercury_deep_copy_body.h:
runtime/mercury_table_type_body.h:
runtime/mercury_tabling.h:
runtime/mercury_tabling_macros.h:
runtime/mercury_unify_compare_body.h:
    Add uint as a builtin type and handle it throughout the runtime.

runtime/mercury_grade.h:
    Bump the binary compatibility version.

runtime/mercury_term_size.c:
runtime/mercury_ml_expand_body.h:
    Handle uint and fix probable bugs with the handling of ints on
    64-bit Windows.
2016-10-24 12:55:35 +11:00
Zoltan Somogyi
31ad78c1a9 Make c_util.m and file_util.m use explicit streams.
compiler/c_util.m:
compiler/file_util.m:
    Replace every predicate that implicitly wrote to the current output stream
    with two predicates: a predicate with the old name that takes an explicit
    output stream parameter, and a predicate that still writes to the current
    output stream, but whose name makes this fact clear.

    Make some other minor improvements.

compiler/bytecode.m:
compiler/elds_to_erlang.m:
compiler/export.m:
compiler/fact_table.m:
compiler/layout_out.m:
compiler/llds_out_data.m:
compiler/llds_out_file.m:
compiler/llds_out_global.m:
compiler/llds_out_instr.m:
compiler/llds_out_util.m:
compiler/mlds_to_c.m:
compiler/mlds_to_cs.m:
compiler/mlds_to_java.m:
compiler/rtti_out.m:
    Conform to the changes above.
2016-09-06 20:01:14 +10:00
Zoltan Somogyi
961046dbb0 Avoid using some Mercury keywords.
compiler/prog_data_foreign.m:
compiler/prog_data_pragma.m:
    Avoid using the names of foreign code attributes and pragma components
    as the names of function symbols (and one type) that represent those
    attributes and components. Do this by giving them type-specific prefixes.

    Delete the ref_or_val type, which has been unused since the IL backend
    was deleted.

compiler/*.m
    Conform to the changes above.
2016-05-14 10:24:13 +10:00
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
cac8f537fb Fix comments. 2016-02-22 11:31:59 +11:00
Mark Brown
3acbf03059 Implement combined higher-order types and insts.
These allow types to be defined in the following manner:

    :- type job ---> job(pred(int::out, io::di, io::uo) is det).

For any construction unification using this functor the argument must
have the required higher-order inst; it is a mode error if it does not.
When terms of type job with inst ground are deconstructed, the argument
is inferred to have the given inst, allowing a higher-order call in that
mode.

The new type syntax is currently only permitted as the direct argument of
a functor in a du type definition. In future it would be meaningful to
support this syntax in other locations, but that is left for a separate
change.

In order to correctly implement the construct/3 library predicate, we
need to be able to dynamically check that arguments do not violate
any constraints on the argument insts. At the moment, we conservatively
abort if any such constraints are present irrespective of whether they
are satisfied or not. Since these constraints are a new feature, no
existing code will abort in this way.

The implementation refers to the inst information associated with types
as "subtype information". This is because, generally, we think of the
combination of a type with a fully bound inst (i.e., one that describes
terms that contain no unbound variables) describes a subtype of that type.

compiler/inst_util.m:
	Ensure that arguments have the necessary insts in construction
	unifications.

	Where available, propagate the insts into arguments rather than
	using ground(shared, none).

compiler/prog_io_type_name.m:
	Parse the new form of types.

compiler/unparse.m:
	Unparse the new form of types.

compiler/prog_io_type_defn.m:
	Allow the new form of types in functor arguments.

compiler/prog_ctgc.m:
compiler/prog_io_item.m:
compiler/prog_io_mutable.m:
compiler/prog_io_pragma.m:
compiler/prog_io_typeclass.m:
compiler/superhomogeneous.m:
	Disallow the new form of types in places other than functor
	arguments.

compiler/prog_data.m:
	Go back to representing function types with result type appended
	to the arguments. In most case this now results in simpler code.

compiler/prog_type.m:
	Abstract away the representation of predicate vs function arguments
	by using a predicate to construct these types.

compiler/rtti.m:
compiler/type_ctor_info.m:
	Include subtype information about the arguments of a du functor
	and about the argument of a notag functor. Generate this
	information from the argument types.

	Currently, the information is one bit which says whether or not
	any subtypes exist in the arguments.

	Bump the RTTI version number from the compiler side.

compiler/rtti_out.m:
	Output functor subtype information for the low-level C backend.

compiler/rtti_to_mlds.m:
	Include functor subtype information in the MLDS.

compiler/mlds_to_cs.m:
	Add the new runtime type to the special cases.

compiler/erl_rtti.m:
compiler/erlang_rtti.m:
library/erlang_rtti_implementation.m:
	Include functor subtype info in the erlang RTTI.

java/runtime/DuFunctorDesc.java:
java/runtime/FunctorSubtypeInfo.java:
	Include functor subtype information in the Java runtime.

runtime/mercury_dotnet.cs.in:
	Include functor subtype information in the C# runtime.

runtime/mercury_type_info.h:
	Include functor subtype information in the C runtime.

	Bump the RTTI version number in the runtime.

	Define macros to access the new field. These macros can correctly
	handle the previous RTTI version, therefore we do not need to
	change the minimum version at this time.

library/private_builtin.m:
	Define constants for use by the Java backend.

library/construct.m:
library/rtti_implementation.m:
	Use the new RTTI to ensure we don't attempt to construct terms
	that violate the new insts.

compiler/prog_rep_tables.m:
	Ignore the new inst info for now.

compiler/*.m:
	Changes to conform to above.

doc/reference_manual.texi:
	Document the new feature.

tests/hard_coded/functor_ho_inst.{m,exp}:
tests/hard_coded/functor_ho_inst_2.{m,exp}:
tests/hard_coded/functor_ho_inst_excp.{m,exp}:
tests/hard_coded/functor_ho_inst_excp_2.{m,exp}:
	Test the new functionality.

tests/invalid/combined_ho_type_inst.{m,err_exp}:
tests/invalid/combined_ho_type_inst_2.{m,err_exp}:
	Test that we don't allow the new types where they are not permitted,
	or are incomplete.

tests/invalid/functor_ho_inst_bad.{m,err_exp}:
tests/invalid/functor_ho_inst_bad_2.{m,err_exp}:
tests/invalid/functor_ho_inst_bad_3.{m,err_exp}:
	Test that the argument inst information is enforced as required.

tests/hard_coded/Mmakefile:
tests/invalid/Mmakefile:
	Run the new test cases.
2016-02-08 16:09:01 +11:00
Julien Fischer
3dd02876a5 Delete the MLDS->IL backend.
compiler/mlds_to_il.m:
compiler/mlds_to_ilasm.m:
compiler/mlds_to_managed.m:
compiler/il_peephole.m:
compiler/ilasm.m:
compiler/ilds.m:
    Delete the modules making up the MLDS->IL code generator.

compiler/globals.m:
compiler/prog_data.m:
    Delete IL as a target and foreign language.

compiler/prog_io_pragma.m:
    Delete the max_stack_size/1 foreign proc attribute.  This was only
    ever required by the IL backend.

compiler/options.m
    Delete options used for the IL backend.

compiler/write_deps_file.m:
    Don't generate mmake targets for .il files etc.

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

compiler/notes/compiler_design.html
compiler/notes/work_in_progress.html
    Conform to the above changes.

library/*.m:
    Delete IL foreign_proc and foreign_export pragmas.

README.DotNet:
    Delete this file.

browser/Mmakefile:
compiler/Mmakefile:
deep_profiler/Mmakefile:
mdbcomp/Mmakefile:
mfilterjavac/Mmakefile:
profiler/Mmakefile:
runtime/Mmakefile:
slice/Mmakefile:
    Conform the above changes.

configure.ac:
    Don't check that IL is a supported foreign language when performing the
    up-to-date check.

    Delete the '--enable-dotnet-grades' option.

scripts/Mmake.vars.in:
    Delete variables used for the IL backend (and in on case by the Aditi
    backend).

scripts/Mercury.config.bootstrap.in:
scripts/Mercury.config.in:
scripts/Mmake.rules:
scripts/canonical_grade.sh-subr:
tools/bootcheck:
    Delete stuff related to the 'il' and 'ilc' grades.

doc/reference_manual.texi:
     Delete the documentation of the 'max_stack_size' option.

doc/user_guide.texi:
     Delete stuff related to the IL backend.

tests/hard_coded/csharp_test.{m,exp}:
tests/invalid/foreign_type_missing.{m,err_exp}:
tests/valid/csharp_hello.m:
	Delete these tests: they are no longer relevant.

tests/hard_coded/equality_pred_which_requires_boxing.m:
tests/hard_coded/foreign_import_module.m:
tests/hard_coded/foreign_import_module_2.m:
tests/hard_coded/foreign_type.m:
tests/hard_coded/foreign_type2.m:
tests/hard_coded/foreign_type3.m:
tests/hard_coded/intermod_foreign_type2.m:
tests/hard_coded/lp.m:
tests/hard_coded/user_compare.m:
tests/invalid/foreign_type_2.m:
tests/invalid/foreign_type_missing.{m,err_exp}:
tests/invalid/foreign_type_visibility.m:
tests/invalid/illtyped_compare.{m,err_exp}:
tests/submodules/external_unification_pred.m
tests/valid/big_foreign_type.m
tests/valid/solver_type_bug.m
tests/valid_seq/foreign_type_spec.m
tests/valid_seq/intermod_impure2.m
    Delete IL foreign_procs where necessary.

tests/hard_coded/Mmakefile
tests/invalid/Mercury.options
tests/invalid/Mmakefile
tests/submodules/Mmakefile
tests/valid/Mercury.options
tests/valid/Mmake.valid.common
tests/valid/Mmakefile
tests/valid_seq/Mmakefile
tests/valid_seq/Mercury.options
    Conform to the above changes.
2015-09-21 11:34:46 +10:00
Zoltan Somogyi
410c75c81f Respect --no-line-numbers-for-c-headers when writing .mh files.
This fixes mantis bug 393.

We already had an option named line_numbers_for_c_headers that was
supposed to govern whether we put #line directives into C header files,
While the default for the line_numbers option is "on", the default for
line_numbers_for_c_headers is "off".

The bug was that the distinction between the two options was respected only
by the code that output .mih files (in mlds_to_c.m), and not by the separate
code that output .mh files (in export.m).

compiler/c_util.m:
    Change the predicates that output #line directives. Previously, they
    always looked up the value of the line_numbers option. Now, they
    use a flag provided by the caller.

    Fix a sort-of related bug: we never write to .mh files, we write to .mh.tmp
    files, and then rename them to .mh. This meant that the code that reset
    the context after a code inclusion reset it to a file name that shortly
    wouldn't exist. Fix that by getting the caller to provide the eventual
    name, with the .mh suffix.

compiler/export.m:
    Pass the flag based on the value of line_numbers_for_c_headers,
    and the eventual name of the file being written, not its current name.

compiler/llds_out_util.m:
compiler/mlds_to_c.m:
compiler/mlds_to_managed.m:
    Conform to the change in c_util.m.
2015-09-18 05:01:49 +10:00
Zoltan Somogyi
fa9213bb80 Convert (C->T;E) to (if C then T else E). 2015-09-17 17:16:18 +10:00
Zoltan Somogyi
bb394448df Group related fields of proc_infos.
compiler/hlds_pred.m:
    As above.

    Give the fields of proc_infos and proc_sub_infos a distinguishing prefix.
    Give some fields more meaningful names.

    Put both the declarations and the definition of the getter and setter
    predicates in the same order as the fields. Give some of those predicates
    more meaningful names.

compiler/export.m:
compiler/hlds_out_pred.m:
compiler/modecheck_call.m:
compiler/modes.m:
compiler/unify_proc.m:
compiler/unique_modes.m:
    Conform to the changes in getter/setter predicate names.
2015-09-15 06:43:09 +10:00
Zoltan Somogyi
656493dfdf Use separate types for the status of different entity kinds.
We used the old import_status type to represent the status of six different
kinds of entities:

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

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

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

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

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

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

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

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

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

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

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

    Update the predicates that test predicate statuses accordingly.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

    In some places, import parse_tree.prog_item as well as hlds.status,
    even if we are only intested in statuses, because the import_locn type,
    which part of some statuses, *is* used in the parse_tree package,
    and must therefore be defined there. These undesirable dependencies
    will go away when we implement the proposal for purpose-specific status
    types.
2015-09-09 01:47:08 +10:00
Zoltan Somogyi
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