Commit Graph

7 Commits

Author SHA1 Message Date
Zoltan Somogyi
5251f76ab6 Simplify the code writing out LLDS C code.
compiler/llds_out_util.m:
    Add decl_set_insert_new, which combines decl_set_is_member and
    decl_set_insert in their typical usage pattern.

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/rtti_out.m:
    Use decl_set_insert_new where applicable.

    Replace sequences of calls to io.write_{string,int}s with calls to
    io.format.
2022-10-01 19:27:54 +10:00
Zoltan Somogyi
5f50259d16 Write to explicitly named streams in many modules.
Right now, most parts of the compiler write to the "current output stream".
This was a pragmatic choice at the time, but has not aged well. The problem
is that the answer to the question "where is the current output stream going?"
is not obvious in *all* places in the compiler (although it is obvious in
most). When using such implicit streams, finding where the output is going
to in a given predicate requires inspecting not just the ancestors of that
predicate, but also all their older siblings (since any of them could have
changed the current stream), *including* their entire call trees. This is
usually an infeasible task. By constrast, if we explicitly pass streams
to all output operations, we need only follow the places where the variable
representing that stream is bound, which the mode system makes easy.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

NEWS:
    Announce the change.

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

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

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

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

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

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

    Change the interface of special_handler to make the above possible.

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

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

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

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

    Add some XXXs.

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

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

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

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

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

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

    In an unrelated change, factor out a duplicate call.
2020-09-28 18:16:13 +10:00
Zoltan Somogyi
4ef4402ecf Make --warn-inconsistent-pred-order-clauses default for the compiler.
compiler/COMP_FLAGS.in:
    As above.

compiler/Mercury.options:
    List the modules for we need --no-warn-inconsistent-pred-order-clauses
    for now.

compiler/call_gen.m:
compiler/code_util.m:
compiler/deep_profiling.m:
compiler/equiv_type.m:
compiler/error_util.m:
compiler/exprn_aux.m:
compiler/get_dependencies.m:
compiler/global_data.m:
compiler/layout_out.m:
compiler/liveness.m:
compiler/ll_pseudo_type_info.m:
compiler/llds.m:
compiler/llds_out_code_addr.m:
compiler/llds_out_data.m:
compiler/module_cmds.m:
compiler/module_qual.m:
compiler/module_qual.qualify_items.m:
compiler/opt_debug.m:
compiler/parse_class.m:
compiler/parse_goal.m:
compiler/parse_sym_name.m:
compiler/parse_type_defn.m:
compiler/rtti_out.m:
compiler/stack_layout.m:
compiler/trace_gen.m:
    Fix issues reported by --warn-inconsistent-pred-order-clauses
    for these modules.
2019-08-23 18:36:18 +10:00
Zoltan Somogyi
cc9912faa8 Don't import anything in packages.
Packages are modules whose only job is to serve as a container for submodules.
Modules like top_level.m, hlds.m, parse_tree.m and ll_backend.m are packages
in this (informal) sense.

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

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

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

This diff removes all import_module declarations from the packages,
and replaces them with import_module declarations in the modules that need
them. This includes only a SUBSET of their child modules and of the non-child
modules that import them.
2015-11-13 15:03:20 +11:00
Zoltan Somogyi
ffe7563530 Convert (C->T;E) to (if C then T else E). 2015-09-17 15:12:20 +10:00
Zoltan Somogyi
30aafc69a0 Split up three big compiler modules: llds_out.m, hlds_out.m (5000+ lines each)
Estimated hours taken: 12
Branches: main

Split up three big compiler modules: llds_out.m, hlds_out.m (5000+ lines each)
and deep_profiling.m (3000+ lines). Put the predicates in the resulting
smaller modules into cohesive groups where possible. A few of the predicates
in the original modules were unused; this diff deletes them.

There are no algorithmic changes.

compiler/llds_out_code_addr.m:
	New module containing the part of llds_out.m that outputs
	code addresses and labels.

compiler/llds_out_data.m:
	New module containing the part of llds_out.m that outputs
	lvals, rvals and their components.

compiler/llds_out_global.m:
	New module containing the part of llds_out.m that generates
	global static C data structures.

compiler/llds_out_instr.m:
	New module containing the part of llds_out.m that outputs
	instructions

compiler/llds_out_file.m:
	New module containing the top level part of llds_out.m,
	which coordinates the generation of a whole C source file.

compiler/llds_out_util.m:
	New module containing the utility parts of llds_out.m.

compiler/llds_out.m:
	Replace everything in this file with just the includes of the
	submodules that now have all its previous contents.

compiler/hlds_llds.m:
	Move a predicate here from llds_out.m, since it is a utility
	predicate operating on a type defined here.

compiler/rtti_out.m:
	Move a predicate here from llds_out.m, since it is a predicate
	generating output from a rtti type.

compiler/hlds_out_mode.m:
	The part of hlds_out.m that deals with writing out insts and modes.

compiler/hlds_out_goal.m:
	The part of hlds_out.m that deals with writing out goals.

compiler/hlds_out_pred.m:
	The part of hlds_out.m that deals with writing out predicates and
	procedures.

compiler/hlds_out_module.m:
	The part of hlds_out.m that deals with writing out module-wide tables.

compiler/hlds_out_util.m:
	Parts of hlds_out.m that don't fit in anywhere else.

compiler/hlds_out.m:
	Replace everything in this file with just the includes of the
	submodules that now have all its previous contents.

compiler/simplify.m:
compiler/hlds_goal.m:
	Move some insts from simplify.m to hlds_goal.m to allow
	hlds_out_goal.m to use them also.

compiler/coverage_profiling.m:
	The part of deep_profiling.m that deals with coverage profiling.

compiler/deep_profiling.m:
	Remove the code moved to coverage_profiling.m, and export the utility
	predicates needed by coverage_profiling.m.

	Remove the things moved to prog_data.m and hlds_goal.m.

	Put the predicates into a more logical order.

compiler/hlds_goal.m:
	Move some predicates here from deep_profiling.m, since they
	belong here.

compiler/prog_data.m:
	Move a type from deep_profiling.m here, since it belongs here.

compiler/add_pragma.m:
	Add a predicate from llds_out.m that is used only here.

compiler/*.m:
	Conform to the changes above.
2009-11-04 03:44:52 +00:00