Commit Graph

6 Commits

Author SHA1 Message Date
Zoltan Somogyi
62ec97d443 Report imports shadowed by other imports.
If a module has two or more import_module or use_module declarations
for the same module, (typically, but not always, one being in its interface
and one in its implementation), generate an informational message about
each redundant declaration if --warn-unused-imports is enabled.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

compiler/prog_item.m:
    Add a convenience predicate.

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

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

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

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

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

    In a few cases, conform to other changes above.

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

tests/*/*.{m,*exp}:
    Delete unneeded imports, and update any expected error messages
    to expect the now-smaller line numbers.
2015-08-25 00:38:49 +10:00
Zoltan Somogyi
fdd141bf77 Clean up the tests in the other test directories.
tests/invalid/*.{m,err_exp}:
tests/misc_tests/*.m:
tests/mmc_make/*.m:
tests/par_conj/*.m:
tests/purity/*.m:
tests/stm/*.m:
tests/string_format/*.m:
tests/structure_reuse/*.m:
tests/submodules/*.m:
tests/tabling/*.m:
tests/term/*.m:
tests/trailing/*.m:
tests/typeclasses/*.m:
tests/valid/*.m:
tests/warnings/*.{m,exp}:
    Make these tests use four-space indentation, and ensure that
    each module is imported on its own line. (I intend to use the latter
    to figure out which subdirectories' tests can be executed in parallel.)

    These changes usually move code to different lines. For the tests
    that check compiler error messages, expect the new line numbers.

browser/cterm.m:
browser/tree234_cc.m:
    Import only one module per line.

tests/hard_coded/boyer.m:
    Fix something I missed.
2015-02-16 12:32:18 +11:00
Peter Wang
9017100dd8 Add an optional argument to the specified' attribute of pragma memo' that
Estimated hours taken: 3
Branches: main

Add an optional argument to the `specified' attribute of `pragma memo' that
allows the user to choose to table arguments introduced by the polymorphism
transformation by address instead of by value.  e.g.

    :- pragma memo(p/2, [specified([addr, output], hidden_arg_addr)]).

Also accept `hidden_arg_value'.

compiler/prog_io_pragma.m:
	Accept the optional argument when parsing `pragma memo'.

	Add some missing spaces in long error messages.

compiler/prog_data.m:
	Hold the tabling method for hidden arguments when the `specified'
	attribute is used.

compiler/table_gen.m:
	Respect the hidden argument tabling method.

	Allow typeclass_infos and base_typeclass_infos to be tabled by address
	instead of aborting.  The compiler still aborts if asked to table them
	by value, as it's not yet implemented.

compiler/add_pragma.m:
compiler/hlds_out.m:
compiler/mercury_to_mercury.m:
	Conform to the changes above.

doc/reference_manual.texi:
	Add (currently commented out) documentation for the `hidden_arg_value'
	and `hidden_arg_addr' options.

tests/tabling/Mmakefile:
tests/tabling/specified_hidden_arg.exp:
tests/tabling/specified_hidden_arg.m:
tests/invalid/specified.err_exp:
tests/invalid/specified.m:
	Add test cases.
2007-11-16 03:44:54 +00:00
Zoltan Somogyi
74ce85d476 Provide a mechanism for collecting statistics about tabling operations,
Estimated hours taken: 60
Branches: main

Provide a mechanism for collecting statistics about tabling operations,
and provide a much more convenient mechanism for resetting tables.

Since it would too complex to do this while preserving the capability
of setting --tabling-via-extra-args to no, eliminate that capability
and the option. That option was useful only for measurements of the
performance boost from setting --tabling-via-extra-args to yes in any case,
so users lose no functionality.

Previously, the only way to debug the low level details of the tabling
mechanism was to build a runtime with a specific C macro (MR_TABLE_DEBUG)
and link with that runtime; this was cumbersome. Change that so that
every one of the debuggable tabling macros has a bool argument that says
whether debugging is enabled or not. The compiler can then set this to
MR_TRUE if the new option --table-debug is given, and to MR_FALSE otherwise.
If set to MR_FALSE, the C compiler should optimize away the debug code,
with zero impact on program size or speed.

Since these changes to macros require nontrivial bootstrapping, which we don't
want to do unnecessarily, modify the interface of the tabling macros as
required to support size limits on tables. This diff also implements the
parsing of size limit specifications on tables, but does not implement them
yet; that is for a future change.

To make the syntax simpler, this diff deletes the free-standing fast_loose_memo
pragma. The same functionality is now available with a fast_loose annotation
on an ordinary memo pragma.

Make a bunch of changes to improve readability and maintainability
in the process. These mostly take the form of renaming ambiguous and/or
not sufficiently expressive function symbols.

runtime/mercury_stack_layout.h:
runtime/mercury_tabling.h:
	Move the description of structure of tables from mercury_stack_layout.h
	to mercury_tabling.h, since we now need it for statistics even if
	execution tracing is not enabled.

	Modify those data structures to have room for the statistics.

	Don't distinguish "strict", "fast_loose" and "specified" memoing
	as separate eval methods; treat them as just different kinds
	of the same eval method: "memo".

	Remove underscores from the names of some types that the style guide
	says shouldn't be there.

runtime/mercury_tabling_preds.h:
runtime/mercury_tabling_macros.h:
	Modify the approach we use for macros that implement the predicates
	of library/table_builtin.m. Instead of selecting between debug and
	nondebug based on whether MR_TABLE_DEBUG is defined or not, add
	an explicit argument controlling this to each debuggable macro.
	The advantage of the new arrangement is that it scales. Another
	argument controls whether we are computing statistics (and if yes,
	where do we put it), and a third argument controls whether we maintain
	back links in the tries and hash tables (this last argument is present
	but is ignored for now).

	Since the values of the arguments will be known when the .c files
	containing calls to these macros are compiled, we pay the space and
	time cost of debugging, statistics gathering and the maintenance of
	back links if and only we need the revelant functionality.

	Provide macros for limited backward compatibility with the old set
	of macros; these allow workspaces created by old compilers to work
	with the new macros in the runtime. The old macros followed the
	naming scheme MR_table_*, the new ones are named MR_tbl_*.

runtime/mercury_table_int_fix_index_body.h:
runtime/mercury_table_int_start_index_body.h:
runtime/mercury_table_type_body.h:
	New files containing parts of the old mercury_tabling.c. Each of these
	files contains the body of the functions that used to be in
	mercury_tabling.c. The new mercury_tabling.c #includes each of these
	files more than once, to provide more than one variant of the old
	function. These variants differ in aspects such as whether debugging
	is enabled or statistics is being collected. Each variant therefore
	incurs only the time costs it needs to. (We pay the space cost of
	having all these variants all the time of course, but this cost
	is negligible.)

runtime/mercury_tabling_stats_defs.h:
runtime/mercury_tabling_stats_nodefs.h:
runtime/mercury_tabling_stats_undefs.h:
	New files that serve as wrappers around the newly #included files,
	controlling how they handle statistics.

runtime/mercury_tabling.c:
	Delete functions now in the new files, and #include them instead.
	Delete the data structures that used to contain summary statistics;
	the new approach keeps statistics in compiler-generated,
	procedure-specific data structures.

runtime/mercury_trace_base.c:
	Use the new versions of the tabling macros to access the I/O table.

runtime/mercury_type_info.h:
	Update some documentation for the movement of code out of
	mercury_tabling.c.

runtime/mercury_types.h:
	Provide forward declarations of the identifiers denoting the new types
	in mercury_tabling.h.

runtime/mercury_grade.h:
	Increment the exec trace version number, since we have changed
	a part of the exec trace structure.

runtime/mercury_bootstrap.h:
	Fix some temporary issues that arise from some renames above.

runtime/mercury_hash_lookup_or_add_body.h:
	Fix comment.

runtime/Mmakefile:
	Mention the new files and the dependencies that involve them.

library/table_builtin.m:
	Provide a type for representing statistics and a predicate for
	printing statistics.

	Use the updated versions of the macros in
	runtime/mercury_tabling_preds.h.

compiler/prog_item.m:
	Change representation of tabling pragmas to allow room for the new
	attributes.

	Allow an item to be marked as being generated by the compiler
	as a result of a pragma memo attribute. We use this for the reset
	and statistics predicates.

compiler/mercury_to_mercury.m:
	Write out the new attributes of the tabling pragma.

compiler/prog_data.m:
compiler/hlds_data.m:
	Change the cons_id that used to refer to a procedure's call table root
	to refer to the entirety of the new data structure now containing it.
	The compiler now needs a way to refer to the other components of this
	new data structure, since it contains the statistics.

	As in the runtime, don't distinguish "strict", "fast_loose" and
	"specified" memoing as separate eval methods; treat them as just
	different kinds of the same eval method: "memo".

	Rename some of the uses of the function symbols "c", "java", "il".

compiler/hlds_pred.m:
	Add an extra field in proc_infos for storing any tabling attributes.

	Change the existing proc_info field that records information about
	the kinds of arguments of tabled procedures to record the information
	needed by the debugger too. This was needed to allow us to shift all
	the RTTI for procedure-specific tables (as opposed to the RTTI for
	the global I/O table) from mercury_stack_layout.h to mercury_tabling.h
	without duplicating the data (which would be a maintenance problem).

	Reformat some comments to make them easier to read.

compiler/layout.m:
compiler/layout_out.m:
	Delete the part of the exec trace information that used to record
	RTTI for tables, since this information is not generated only as
	part of the debugger data structures anymore.

compiler/prog_io_pragma.m:
	Recognize the updated syntax for tabling pragmas.

compiler/add_pragma.m:
	When processing tabling pragmas for inclusion in the HLDS, create
	any reset and statistics predicates they ask for.

compiler/make_hlds_passes.m:
	Export a predicate now needed by add_pragma.m.

	Handle the new attributes on tabling pragmas

compiler/globals.m:
	Change the function symbols of the types describing backends and
	foreign languages to say what they are. Previously, both types (as well
	as several others) included the function symbol "c"; now, they are
	target_c and lang_c respectively.

compiler/table_gen.m:
	Implement the changes described at the top.

	When passing around varsets and vartypes, pass the arguments in the
	standard order.

compiler/goal_util.m:
compiler/hlds_goal.m:
	When passing around varsets and vartypes, pass the arguments in the
	standard order.

compiler/rtti.m:
	Provide types for representing the runtime's data structures for
	tabling (which are now significantly more complex than a single word)
	and predicates for manipulating them, for use by both the ml and ll
	backends.

compiler/llds.m:
	Replace the comp_gen_c_var type with the tabling_info_struct type,
	which contains the information needed to create the per-procedure
	tabling data structures.

	Replace references to call tables with references to the various
	components of the new tabling data structures.

compiler/llds_out.m:
	Add code to write out tabling_info_structs.

	Delete the code required for the old, hacky way of resetting tables.

	Reorder some code more logically.

compiler/proc_gen.m:
	Generate tabling_info_structs.

compiler/stack_layout.m:
	Don't generate the information now generated in proc_gen.m.

compiler/mlds.m:
	Give mlds_proc_labels their own function symbols, instead of using
	a pair. Rename some other function symbols to avoid ambiguity and add
	expressiveness.

	Provide for the representation of references to the various components
	of the new tabling data structures, and for the representation of their
	types.

compiler/ml_code_gen.m:
	When generating code for a tabled procedure, generate also the data
	structures required for its table.

compiler/rtti_to_mlds.m:
compiler/ml_util.m:
	Move some predicates from rtti_to_mlds.m to ml_util.m, since we
	now also want to call them from ml_code_gen.m.

compiler/name_mangle.m:
	Add some utility predicates.

compiler/options.m:
	Delete the old --allow-table-reset option.

	Add the new --table-debug option.

	Comment out an implementor-only option.

compiler/add_pred.m:
compiler/add_solver.m:
compiler/add_trail_ops.m:
compiler/add_type.m:
compiler/bytecode_gen.m:
compiler/code_gen.m:
compiler/compile_target_code.m:
compiler/complexity.m:
compiler/dependency_graph.m:
compiler/det_report.m:
compiler/export.m:
compiler/fact_table.m:
compiler/foreign.m:
compiler/global_data.m:
compiler/globals.m:
compiler/handle_options.m:
compiler/higher_order.m:
compiler/hlds_code_util.m:
compiler/hlds_data.m:
compiler/hlds_goal.m:
compiler/hlds_out.m:
compiler/inlining.m:
compiler/intermod.m:
compiler/make.dependencies.m:
compiler/make.module_target.m:
compiler/make.program_target.m:
compiler/make.util.m:
compiler/make_hlds_passes.m:
compiler/mercury_compile.m:
compiler/ml_call_gen.m:
compiler/ml_closure_gen.m:
compiler/ml_code_gen.m:
compiler/ml_code_util.m:
compiler/ml_elim_nested.m:
compiler/ml_optimize.m:
compiler/ml_switch_gen.m:
compiler/ml_tailcall.m:
compiler/ml_type_gen.m:
compiler/ml_unify_gen.m:
compiler/mlds_to_c.m:
compiler/mlds_to_gcc.m:
compiler/mlds_to_il.m:
compiler/mlds_to_ilasm.m:
compiler/mlds_to_java.m:
compiler/mlds_to_managed.m:
compiler/modes.m:
compiler/module_qual.m:
compiler/modules.m:
compiler/opt_debug.m:
compiler/opt_util.m:
compiler/polymorphism.m:
compiler/pragma_c_gen.m:
compiler/proc_label.m:
compiler/prog_data.m:
compiler/prog_foreign.m:
compiler/prog_item.m:
compiler/prog_mutable.m:
compiler/prog_out.m:
compiler/prog_rep.m:
compiler/prog_util.m:
compiler/recompilation.version.m:
compiler/size_prof.m:
compiler/special_pred.m:
compiler/switch_util.m:
compiler/transform_llds.m:
compiler/tupling.m:
compiler/type_ctor_info.m:
compiler/unify_gen.m:
	Conform to the changes above, and/or improve some comments.

mdbcomp/prim_data.m:
	Make the names of the function symbols of the proc_label type more
	expressive and less ambiguous.

mdbcomp/prim_data.m:
mdbcomp/mdbcomp.m:
mdbcomp/program_representation.m:
mdbcomp/rtti_access.m:
mdbcomp/slice_and_dice.m:
mdbcomp/trace_counts.m:
	Use . instead of __ as module qualifier.

	Conform to the change to prim_data.m.

browser/declarative_execution.m:
browser/declarative_oracle.m:
browser/declarative_tree.m:
	Conform the change to mdbcomp/prim_data.m.

tests/debugger/Mercury.options:
	Don't specify --allow-table-reset for fib.m, since that option
	doesn't exist anymore.

tests/debugger/fib.m:
	Use the new mechanism for resetting the table.

tests/debugger/print_table.m:
	Use the new syntax for pragma memo attributes.

tests/invalid/specified.{m,err_exp}:
	Use to the new syntax and reset method for pragma memo attributes.
	Test the handling of errors in the new attribute syntax.

tests/tabling/Mercury.options:
	Don't specify --allow-table-reset for specified.m, since that option
	doesn't exist anymore.

tests/tabling/specified.m:
	Use the new syntax for pragma memo attributes, and use the new
	mechanism for resetting tables. We could also use this test case
	for testing the printing of statistics, but the format of that
	output is still not final.

tests/tabling/fast_loose.m:
	Use the new syntax for pragma memo attributes, and use the new
	mechanism for resetting tables.

trace/mercury_trace.c:
trace/mercury_trace_cmd_developer.c:
	Conform to the changes in the RTTI data structures regarding tabling.

	Remove underscores from the names of some types that the style guide
	says shouldn't be there.

library/robdd.m:
	Comment out the tabling pragma until this change is bootstrapped.
	Without this, the conflict between the old calls to macros generated
	by the existing compiler and the new definition of those macros
	in the runtime would cause errors from the C compiler.
2006-06-08 08:20:17 +00:00
Julien Fischer
459847a064 Move the univ, maybe, pair and unit types from std_util into their own
Estimated hours taken: 18
Branches: main

Move the univ, maybe, pair and unit types from std_util into their own
modules.  std_util still contains the general purpose higher-order programming
constructs.

library/std_util.m:
	Move univ, maybe, pair and unit (plus any other related types
	and procedures) into their own modules.

library/maybe.m:
	New module.  This contains the maybe and maybe_error types and
	the associated procedures.

library/pair.m:
	New module.  This contains the pair type and associated procedures.

library/unit.m:
	New module. This contains the types unit/0 and unit/1.

library/univ.m:
	New module. This contains the univ type and associated procedures.

library/library.m:
	Add the new modules.

library/private_builtin.m:
	Update the declaration of the type_ctor_info struct for univ.

runtime/mercury.h:
	Update the declaration for the type_ctor_info struct for univ.

runtime/mercury_mcpp.h:
runtime/mercury_hlc_types.h:
	Update the definition of MR_Univ.

runtime/mercury_init.h:
	Fix a comment: ML_type_name is now exported from type_desc.m.

compiler/mlds_to_il.m:
	Update the the name of the module that defines univs (which are
	handled specially by the il code generator.)

library/*.m:
compiler/*.m:
browser/*.m:
mdbcomp/*.m:
profiler/*.m:
deep_profiler/*.m:
	Conform to the above changes.  Import the new modules where they
	are needed; don't import std_util where it isn't needed.

	Fix formatting in lots of modules.  Delete duplicate module
	imports.

tests/*:
	Update the test suite to confrom to the above changes.
2006-03-29 08:09:58 +00:00
Zoltan Somogyi
f7c8e5899d Add a new tabling method, one which specifies how each argument should
Estimated hours taken: 20
Branches: main

Add a new tabling method, one which specifies how each argument should
be treated, like this:

    :- pragma memo(p(in, in, in, out), [value, addr, promise_implied, output]).

doc/reference_manual.texi:
	Document the new tabling method.

compiler/prog_data.m:
	Add a new tabling method, one which specifies how each argument should
	be treated.

compiler/hlds_pred.m:
	Provide for the description of untabled input arguments of tabled
	procedures.

compiler/prog_io_pragma.m:
	Parse the new tabling method.

	Fix a bunch of formatting problems.

compiler/add_pragma.m:
	When adding a tabling pragma to the HLDS, check that if the pragma
	individually specifies the tabling methods of a procedure's arguments,
	then those tabling methods agree with the modes of those arguments.

	Fix an old bug: check whether a tabled predicate's arguments are
	fully input or fully output, and print an error message if not.
	We used to check this only in table_gen.m, but there we could only
	abort the compiler if the check failed.

	Factor out some common code and thereby fix an old bug: check for
	conflicting tabling pragmas not just when adding the pragma to all
	procedures of a predicate, but also when adding it to only a
	specified procedure.

compiler/table_gen.m:
	Implement the new tabling method.

compiler/prog_out.m:
compiler/layout_out.m:
	Conform to the changes above.

runtime/mercury_stack_layout.h:
	Provide for the description of untabled input arguments of tabled
	procedures.

trace/mercury_trace.c:
	Handle the new tabling method.

trace/mercury_trace_internal.c:
	Handle the new tabling method. Delete the defaults from some switches
	on enums to allow gcc to recognize missing cases.

	Handle the untabled input arguments of tabled procedures: skip over
	them when printing procedures' call tables.

	Enable better completion for mdb's "table" command.

trace/mercury_trace_tables.[ch]:
	Rename the breakpoint completer the proc_spec completer, since it does
	completions on procedure specifications.

tests/debugger/print_table.{m,inp,exp}:
	Modify this test case to test the ability to print the tables of
	predicates with some untabled arguments.

tests/tabling/specified.{m,exp}:
	New test case to check the functioning of the new tabling method
	by testing whether it is in fact faster to table the address of
	an argument instead of its value, or to not table it at all.
	Since the gains here are not quite as dramatic as tabled vs untabled,
	use a slightly looser criterion for comparing speeds than we use
	in the various versions of the fib test case.

tests/tabling/Mmakefile:
tests/tabling/Mercury.options:
	Enable the new test case, and set up the option it needs.

tests/invalid/specified.{m,err_exp}:
	New test case, a slight variant of tests/tabling/specified.m,
	to check the compiler's ability to detect errors in the new form
	of tabling pragma.

tests/invalid/Mmakefile:
	Enable the new test case.
2005-08-14 03:20:59 +00:00