Commit Graph

142 Commits

Author SHA1 Message Date
Zoltan Somogyi
62d7496a7e Significant further improvements in the worst-case behavior of the compiler
Estimated hours taken: 16
Branches: main

Significant further improvements in the worst-case behavior of the compiler
when working on code such as zm_eq20.m and zm_coerce_tuples.m. On my laptop,
zm_eq20.m and zm_coerce_tuples.m now compile in 2.5s and 12.9s respectively;
the times before were 86.4s and 54.0s. The sizes of the stage 110 HLDS dumps
(the stage just after lambda expansion) go from 8.5Mb and 760Mb (!) to
just 0.4Mb and 7.4Mb respectively.

compiler/polymorphism.m:
	Remember not just which typeinfos we have constructed, but also what
	type_ctor_infos, base_typeclass_infos and typeclass_infos we have
	constructed, so that we don't have to construct them again for code
	that is executed later.

	The maintenance of the additional maps adds some overhead that in
	typical code probably cannot be made back through the resulting
	reductions in the workload of later compiler passes. However,
	the avoidance of horrible worst-case behavior trumps small increases
	in normal-case runtime.

	For zm_coerce_tuples, polymorphism.m now generates as good HLDS code
	as can be expected within each lambda expression. There is still
	a lot of duplicated code, with each copy being in a different lambda
	expression, but factoring out these commonalities will require a
	fundamentally different approach.

	Avoid using the misleading prefix "TypeClassInfo_" on the names of
	variables holding base_typeclass_infos.

compiler/ml_elim_nested.m:
	Don't look for static definitions where they cannot occur anymore.

	When deciding whether a definition needs to be hoisted out,
	don't look for it being used in later static definitions,
	since all the static definitions are now elsewhere.

	In order to avoid running the compiler out of nondet stack space
	on zm_coerce_tuples.m, avoid the use of enumerating all the
	definitions in a potentially huge piece of MLDS by backtracking.

compiler/hlds_rtti.m:
	Avoid enumerating all the members of a potentially huge list
	by backtracking in order to avoid running the compiler out of nondet
	stack space on zm_coerce_tuples.m.

	I first tried to do this by constructing the list with det code,
	but this turned out not to fix the underlying problem, which was that
	almost all of the list's elements were copies of each other, and we
	then had to get rid of the copies. The actual fix is to gather the
	types we need directly as a set.

	Provide restrict_rtti_varmaps for use by lambda.m.

	Give the field names of the rtti_varmaps type a distinguishing prefix.

compiler/lambda.m:
	The fundamental reason for the bad performance of the equiv_type_hlds
	pass on zm_coerce_tuples.m was that even with the recent improvements
	to polymorphism.m, a couple of big predicates had about ten thousand
	variables each, and when lambda.m created about 200 new procedures
	from the lambda expressions inside them, it duplicated those huge
	vartypes and rtti_varmaps for each one.

	The fix is to restrict the vartypes and the rtti_varmaps of both
	the newly created procedures and the old procedure they were taken from
	to the variables that actually occur in them.

	We could potentially avoid the need to restrict the rtti_varmap
	of the original procedure for the new procedures created for lambda
	goals by having polymorphism.m give each rhs_lambda_goal its own
	rtti_varmap in the first place, but that would be future work.

	Use the "no lambda" version of quantification after the lambda pass,
	since we have just removed all the lambdas from the goal being
	quantified.

	Give the predicates of this module more expressive names.

compiler/mercury_compile.m:
	Conform to the change in lambda.m.

compiler/equiv_type_hlds.m:
	Use specialized versions of the predicates in equiv_type.m, since
	the general versions do some things (finding circularities, recording
	used modules) that this pass does not need. Use some new predicates
	from the standard library to reduce overhead.

compiler/ml_optimize.m:
	In order to avoid running the compiler out of nondet stack space
	on zm_coerce_tuples.m, avoid the use of enumerating all the members
	of a potentially huge list by backtracking.

	Move a cheap test before a more expensive one.

compiler/modes.m:
compiler/modecheck_unify.m:
	Avoid some unnecessary overheads when modechecking typeinfos and
	related variables. One overhead was iteration over a list of exactly
	one element, another is a redundant lookup of the variable's type,
	and the third is the redundant setting of the unify context.

compiler/inst_match.m:
	Use set_tree234s instead sets to keep track of expansions in one group
	of predicates indicated by benchmarking.

library/list.m:
	Add a new predicate, list.find_first_match, which is a version of
	filter that returns only the first matching item. This is for use
	in ml_elim_nested.m.

	Make list.sort_and_remove_dups remove duplicates as it goes,
	not all at the end, since this (a) allows us to avoid a separate
	duplicate-elimination pass at the end, and (b) any duplicate eliminated
	in one merge pass reduces the workload for any later merge passes.

	Put some code in its proper order, since preserving tail recursion
	in Prolog is no longer an issue.

library/map.m:
	Add  versions of map.foldl{,2,3} and map.map_foldl{,2,3} that do not
	pass the key to the higher order argument, for use by some of the
	compiler modules above.

	Group the declarations of all the foldr predicates together.

library/tree.m:
	Make the same changes as in map.m, in order to implement map.m's new
	predicates.

library/varset.m:
	Minor style improvements.

library/set_tree234.m:
	Fix a wrong comment.

NEWS:
	Mention the new additions to the library.
2009-09-16 02:32:56 +00:00
Zoltan Somogyi
77a6a6c10c Implement several more changes that together speed up compilation time
Estimated hours taken: 16
Branches: main

Implement several more changes that together speed up compilation time
on training_cars_full by 12%, and also improve tools/speedtest -h by 7.2%
and tools/speedtest by 1.6%.

The first change is designed to eliminate the time that the compiler spends
constructing error messages that are then ignored. The working predicates of
prog_io_sym_name used to always return a single result, which either gave
a description of the thing being looked, or an error message. However,
in many places, the caller did not consider not finding the thing being looked
for to be an error, and thus threw away the error message, keeping only
the "not found" indication. For each predicate with such callers, this diff
provides a parallel predicate that indicates "not found" simply by failing.
This allows us to eliminate the construction of the error message, the
preparation for the construction of the error message (usually by describing
the context), and the construction of the "ok" wrapper.

The second change is to specialize the handling of from_ground_term_construct
scopes in the termination analyzer. To make this easier, I also cleaned up
of the infrastructure of the termination analyzer.

The third change is to avoid traversing from_ground_term_construct scopes
in quantification.m when finding the variables in a goal, since termination
analysis no longer needs the information it gathers.

The fourth change is to avoid traversing second and later conjuncts in
conjunctions twice. The first step in handling conjunctions is to call
implicitly_quantify_conj, which builds up a data structure that pairs each
conjunct with the variables that occur free in all the conjuncts following it.
However, after this was done and each conjunct was annotated with its
nonlocals, we used to compute the variables that occur free in the conjunction
as a whole from scratch. This diff changes the code so that we now compute that
set based on the information we gathered earlier, avoiding a redundant
traversal.

The fifth change is to create specialized, lower-arity versions of many of
the predicates in quantification.m. These versions are intended for traversals
that take place after the compiler has replaced lambda expressions with
references to separate procedures. These traversals do not need to pass around
arguments representing the variables occurring free in the (now non-existent)
lambda expressions.

compiler/prog_io_sym_name.m:
	Make the first change described above.

	Change some predicate names to adopt a consistent naming scheme
	in which predicates that do the same job and differ only in how they
	handle errors have names that differ only in a "try_" prefix.

	Add some predicate versions that do common tests on the output
	of the base versions. For example, try_parse_sym_name_and_no_args
	is a version of try_parse_sym_name_and_args that insists on finding
	an empty argument list.

	Remove the unused "error term" argument that we used to need a while
	ago.

	Move some predicate definitions to make their order match the order of
	their declarations.

	Turn a predicate into a function for its caller's convenience.

compiler/term_constr_build.m:
	Make the second change described above by modeling each
	from_ground_term_construct scope as a single unification,
	assigning the total size of the ground term to the variable being
	built.

compiler/term_constr_util.m:
	Put the arguments of some predicates into a more standard order.

compiler/lp_rational.m:
	Change the names of some function symbols to avoid both the use of
	graphic characters that require quoting and clashes with other types.

	Change the names of some predicates to make their purpose clear,
	and to avoid ambiguity.

compiler/quantification.m:
	Make the third, fourth and fifth changes described above.

compiler/*.m:
	Conform to the changes above.
2009-09-08 02:43:41 +00:00
Zoltan Somogyi
d69ba1a1f0 Include the type_ctor in cons_ids for user-defined types.
Estimated hours taken: 32
Branches: main

Include the type_ctor in cons_ids for user-defined types. The intention is
two-fold:

- It prepares for a future in which we allow more than one function symbol to
  with the same name to be defined in a module.

- It makes the HLDS code more self-contained. In many places, processing
  construction and deconstruction unifications required knowing which type
  the cons_id belongs to, but until now, code couldn't know that unless it
  kept track of the type of the variable unified with the cons_id.

With this diff, user-defined cons_ids are represented as

	cons(SymName, Arity, TypeCtor)

The last field is filled in during post-typecheck. After that time, any module
qualification in the SymName (which may initially be partial) is redundant,
since it is also available in the TypeCtor.

In the future, we could make all those SymNames be just unqualified(_) at that
time. We could also replace the current maps in HLDS type definitions with
full cons_id keys with just name/arity keys (since the module qualifier is a
given for any given type definition), we could also support partially
qualified cons_ids in source code using a map from name/arity pairs to a list
of all the type_ctors that have function symbols with that name/arity, instead
of our current practice of inserting all possible partially module qualified
version of every cons_id into a single giant table, and we could do the same
thing with the field names table.

This diff also separates tuples out from user-defined types, since in many
respects they are different (they don't have a single type_ctor, for starters).
It also separates out character constants, since they were alreay treated
specially in most places, though not in some places where they *ought* to
have been treated specially. Take the opportunity to give some other cons_ids
better names.

compiler/prog_data.m:
	Make the change described above, and document it.

	Put the implementations of the predicates declared in each part
	of this module next to the declarations, instead of keeping all the
	code until the very end (where it was usually far from their
	declarations).

	Remove three predicates with identical definitions from inst_match.m,
	inst_util.m and mode_constraints.m, and put the common definition
	in prog_data.m.

library/term_io.m:
	Add a new predicate that is basically a reversible version of
	the existing function espaced_char, since the definition of char_consts
	needs reversibilty.

compiler/post_typecheck.m:
	For functors of user-defined types, record their type_ctor. For tuples
	and char constants, record them as such.

compiler/builtin_lib_types.m:
compiler/parse_tree.m:
compiler/notes/compiler_design.html:
	New module to centralize knowledge about builtin types, specially
	handled library types, and their function symbols. Previously,
	the stuff now in this module used to be in several different places,
	including prog_type.m and stm_expand.m, and some of it was duplicated.

mdbcomp/prim_data.m:
	Add some predicates now needed by builtin_lib_types.m.

compiler/builtin_ops.m:
	Factor out some duplicated code.

compiler/add_type.m:
	Include the relevant type_ctors in the cons_ids generated in type
	definitions.

compiler/hlds_data.m:
	Document an existing type better.

	Rename a cons_tag in sync with its corresponding cons_id.

	Put some declarations into logical order.

compiler/hlds_out.m:
	Rename a misleadingly-named predicate.

compiler/prog_ctgc.m:
compiler/term_constr_build.m:
	Add XXXs for questionable existing code.

compiler/add_clause.m:
compiler/add_heap_ops.m:
compiler/add_pragma.m:
compiler/add_pred.m:
compiler/add_trail_ops.m:
compiler/assertion.m:
compiler/bytecode_gen.m:
compiler/closure_analysis.m:
compiler/code_info.m:
compiler/complexity.m:
compiler/ctgc_selector.m:
compiler/dead_proc_elim.m:
compiler/deep_profiling.m:
compiler/delay_partial_inst.m:
compiler/dependency_graph.m:
compiler/det_analysis.m:
compiler/det_report.m:
compiler/distance_granularity.m:
compiler/erl_rtti.m:
compiler/erl_unify_gen.m:
compiler/export.m:
compiler/field_access.m:
compiler/foreign.m:
compiler/format_call.m:
compiler/hhf.m:
compiler/higher_order.m:
compiler/hlds_code_util.m:
compiler/hlds_desc.m:
compiler/hlds_goal.m:
compiler/implementation_defined_literals.m:
compiler/inst_check.m:
compiler/inst_graph.m:
compiler/inst_match.m:
compiler/inst_util.m:
compiler/instmap.m:
compiler/intermod.m:
compiler/interval.m:
compiler/lambda.m:
compiler/lco.m:
compiler/make_tags.m:
compiler/mercury_compile.m:
compiler/mercury_to_mercury.m:
compiler/middle_rec.m:
compiler/ml_closure_gen.m:
compiler/ml_code_gen.m:
compiler/ml_code_util.m:
compiler/ml_switch_gen.m:
compiler/ml_type_gen.m:
compiler/ml_unify_gen.m:
compiler/ml_util.m:
compiler/mlds_to_c.m:
compiler/mlds_to_java.m:
compiler/mode_constraints.m:
compiler/mode_errors.m:
compiler/mode_ordering.m:
compiler/mode_util.m:
compiler/modecheck_unify.m:
compiler/modes.m:
compiler/module_qual.m:
compiler/polymorphism.m:
compiler/prog_ctgc.m:
compiler/prog_event.m:
compiler/prog_io_util.m:
compiler/prog_mode.m:
compiler/prog_mutable.m:
compiler/prog_out.m:
compiler/prog_type.m:
compiler/prog_util.m:
compiler/purity.m:
compiler/qual_info.m:
compiler/rbmm.add_rbmm_goal_infos.m:
compiler/rbmm.execution_path.m:
compiler/rbmm.points_to_analysis.m:
compiler/rbmm.region_transformation.m:
compiler/recompilation.usage.m:
compiler/rtti.m:
compiler/rtti_out.m:
compiler/rtti_to_mlds.m:
compiler/simplify.m:
compiler/simplify.m:
compiler/special_pred.m:
compiler/ssdebug.m:
compiler/stack_opt.m:
compiler/stm_expand.m:
compiler/stratify.m:
compiler/structure_reuse.direct.detect_garbagem:
compiler/superhomoegenous.m:
compiler/switch_detection.m:
compiler/switch_gen.m:
compiler/switch_util.m:
compiler/table_gen.m:
compiler/term_constr_build.m:
compiler/term_norm.m:
compiler/try_expand.m:
compiler/type_constraints.m:
compiler/type_ctor_info.m:
compiler/type_util.m:
compiler/typecheck.m:
compiler/typecheck_errors.m:
compiler/unify_gen.m:
compiler/unify_proc.m:
compiler/unify_modes.m:
compiler/untupling.m:
compiler/unused_imports.m:
compiler/xml_documentation.m:
	Minor changes, mostly to ignore the type_ctor in cons_ids in places
	where it is not needed, take the type_ctor from the cons_id in places
	where it is more convenient, conform to the new names of some cons_ids,
	conform to the changes in hlds_out.m, and/or add now-needed imports
	of builtin_lib_types.m.

	In some places, the handling previously applied to cons/2 (which
	included tuples and character constants as well as user-defined
	function symbols) is now applied only to user-defined function symbols
	or to user-defined function symbols and tuples, as appropriate,
	with character constants being handled more like the other kinds of
	constants.

	In inst_match.m, rename a whole bunch of predicates to avoid
	ambiguities.

	In prog_util.m, remove two predicates that did almost nothing yet were
	far too easy to misuse.
2009-06-11 07:00:38 +00:00
Peter Wang
cc8923b7f7 Add support for `try' goals, syntactic sugar on top of the exception handling
Branches: main

Add support for `try' goals, syntactic sugar on top of the exception handling
predicates in the standard library.  The syntax is documented in the reference
manual.  Currently one of the proposed try parameters, io(!IO), is implemented.

Try goals are implemented by *two* source-to-source transformations, one at the
parse tree level, then a later one on the HLDS.  The reason for this is given
in try_expand.m.


library/ops.m:
	Add three new operators: try, catch, catch_any.

library/exception.m:
	Add forwarding predicates so that code generated by the try goal
	transformation doesn't need to import `univ'.

compiler/prog_item.m:
	Add representations of try goals to parse tree.

compiler/prog_io_goal.m:
	Parse try goals.

	Unrelated: fix spelling of "parameter".

compiler/add_clause.m:
	Perform the initial transformation on try goals.

compiler/hlds_goal.m:
	Add try goals to HLDS, as shorthand goals.

compiler/try_expand.m:
	New module to perform the latter transformation on try goals.

compiler/check_hlds.m:
	Import the new module.

compiler/mercury_compile.m:
	Call the try_expand pass near the end of the front-end pass.

compiler/module_imports.m:
	Implicitly import `exception' if a `try' goal is seen.

compiler/det_analysis.m:
	Conform to addition of try goals in HLDS.  Make it not wrap a commit
	scope around the intermediate try goal (as it might if there are no
	outputs) as it is inappropriate.

compiler/prog_util.m:
	Conform to parse tree changes.

compiler/assertion.m:
compiler/build_mode_constraints.m:
compiler/cse_detection.m:
compiler/delay_partial_inst.m:
compiler/dependency_graph.m:
compiler/det_report.m:
compiler/equiv_type_hlds.m:
compiler/format_call.m:
compiler/goal_form.m:
compiler/goal_path.m:
compiler/goal_util.m:
compiler/hlds_out.m:
compiler/intermod.m:
compiler/lambda.m:
compiler/make_hlds_warn.m:
compiler/mercury_to_mercury.m:
compiler/mode_util.m:
compiler/modes.m:
compiler/module_qual.m:
compiler/ordering_mode_constraints.m:
compiler/polymorphism.m:
compiler/post_typecheck.m:
compiler/prop_mode_constraints.m:
compiler/purity.m:
compiler/quantification.m:
compiler/simplify.m:
compiler/stm_expand.m:
compiler/stratify.m:
compiler/structure_reuse.lfu.m:
compiler/switch_detection.m:
compiler/type_constraints.m:
compiler/typecheck.m:
compiler/unique_modes.m:
compiler/unused_imports.m:
	Conform to changes in HLDS.

compiler/il_peephole.m:
compiler/ilasm.m:
compiler/ilds.m:
compiler/mlds_to_il.m:
	Rename some symbols to avoid the new keywords.

library/exception.m:
	Add two helper predicates for the try goal transformations.

doc/reference_manual.texi:
NEWS:
	Document and announce the new language feature.

compiler/notes/compiler_design.html:
	Note new compiler module.

tests/hard_coded/Mmakefile:
tests/hard_coded/try_syntax_1.exp:
tests/hard_coded/try_syntax_1.m:
tests/hard_coded/try_syntax_2.exp:
tests/hard_coded/try_syntax_2.m:
tests/hard_coded/try_syntax_3.exp:
tests/hard_coded/try_syntax_3.m:
tests/hard_coded/try_syntax_4.exp:
tests/hard_coded/try_syntax_4.m:
tests/hard_coded/try_syntax_5.exp:
tests/hard_coded/try_syntax_5.m:
tests/hard_coded/try_syntax_6.exp:
tests/hard_coded/try_syntax_6.m:
tests/hard_coded/try_syntax_7.exp:
tests/hard_coded/try_syntax_7.m:
tests/invalid/Mmakefile:
tests/invalid/try_bad_params.err_exp:
tests/invalid/try_bad_params.m:
tests/invalid/try_io_else.err_exp:
tests/invalid/try_io_else.m:
	Add test cases.

tests/debugger/declarative/catch.m:
	The module name is now a keyword so requires brackets.

tests/invalid/trace_goal_env.err_exp:
	Update test case for fixed spelling for "parameter".

vim/syntax/mercury.vim:
	Add try, catch, catch_any as keywords.
2009-03-10 05:00:34 +00:00
Ben Mellor
edda5238a1 Fix two bugs preventing the use of or_else alternatives to atomic
transaction scopes and nested atomic scopes.

The main issue was the code assuming that the inner stm interface variables
were the same for the main goal and the or_else goals, but quantification
renames these variables to be distinct.


library/stm_builtin.m
    Rename stm_from_outer_to_inner_io and stm_from_inner_to_outer_io, dropping
    the _io suffix. They are used when the outer type is stm as well as io.

compiler/hlds_goal.m
    Add a field to the atomic_goal structure to hold the names of the STM
    interface variables used in each or_else alternative, since quantification
    renames these variables to be distinct from those used in the main atomic
    goal.

compiler/purity.m
    Insert calls to the (renamed) dummy predicates stm_from_outer_to_inner and
    stm_from_inner_to_outer regardless of the type of the outer variable,
    instead of using the nonexistent stm_from_*_to_*_stm versions when the
    outer type is stm. Also use the inner STM interface variables specific to
    each or_else alternative when generating these calls.

compiler/quantification.m
    Explicitly rename the inner STM interface variables in each of the or_else
    alternatives before calling implicitly_quantify_disj, so that the new names
    of these variables can be stored in the atomic_goal structure.

compiler/typecheck.m
    Ensure all the inner STM interface variables are typed stm, not just the
    ones in the main goal.

compiler/add_clause.m
compiler/assertion.m
compiler/build_mode_constraints.m
compiler/cse_detection.m
compiler/delay_partial_inst.m
compiler/dependency_graph.m
compiler/det_analysis.m
compiler/det_report.m
compiler/equiv_type_hlds.m
compiler/format_call.m
compiler/goal_form.m
compiler/goal_path.m
compiler/goal_util.m
compiler/hlds_out.m
compiler/intermod.m
compiler/lambda.m
compiler/make_hlds_warn.m
compiler/mode_util.m
compiler/modes.m
compiler/ordering_mode_constraints.m
compiler/polymorphism.m
compiler/post_typecheck.m
compiler/prop_mode_constraints.m
compiler/simplify.m
compiler/stm_expand.m
compiler/stratify.m
compiler/structure_reuse.lfu.m
compiler/switch_detection.m
compiler/unique_modes.m
compiler/unused_imports.m
    Updated to reflect the extra field in atomic_goal.
2009-02-26 23:43:08 +00:00
Zoltan Somogyi
5ad9a27793 Speed up the compiler's handling of code that constructs large ground terms
Estimated hours taken: 80
Branches: main

Speed up the compiler's handling of code that constructs large ground terms
by specializing the treatment of such code.

This diff reduces the compilation time for training_cars_full.m from 106.9
seconds to 30.3 seconds on alys, my laptop. The time on tools/speedtest
stays pretty much the same.

compiler/hlds_goal.m:
	Record the classification of from_ground_term scopes as purely
	constructing terms, purely deconstructing them or something other.

	Fix an old potential bug: variables inside the construct_how fields
	of unifications weren't being renamed along with other variables.
	This is a bug if any part of the compiler later looks at those
	variables. (I am not sure whether or not this happens.)

compiler/superhomogenous.m:
	Provisionally mark newly constructed static terms as being
	from_ground_term_construct. Mode checking will either confirm this
	or change the scope kind.

compiler/options.m:
compiler/handle_options.m:
	Add a new option, from_ground_term_threshold, that allows the user to
	set the boundary between ground terms that get scopes and ground terms
	do not. I plan to experiment with different settings later.

compiler/modes.m:
	Make this classification. For scopes that construct ground terms,
	use a specialized algorithm that avoids quadratic behavior.
	(It does not access the unify_inst_table, which is where the
	factor of N other than the length of the goal list came from.)
	The total size of the instmap_deltas, if printed out, still looks like
	O(N^2) in size, but due to structure sharing it needs only O(N) memory.

	For scopes that construct ground terms, set the determinism information
	so that det_analysis.m doesn't have to traverse such scopes.

	When handling disjunctions, check whether some nonlocals of the
	disjunctions are constructed by from_ground_term_construct scopes.
	For any such nonlocals, set their insts to just ground, throwing away
	the precise information we have about exactly what function symbols
	they and ALL their subterms are bound to. This is HUGE win, since
	it allows us avoid spending a lot of time building a huge merge_inst
	table, which later passes of the compiler (e.g. equiv_type_hlds) would
	then have to spend similarly huge times traversing.

	This approach does have a down side. If lots of arms of a disjunction
	bind a nonlocal to a large ground term, but a few bind it to a SMALL
	ground term, a term below the from_ground_term_threshold, this
	optimization won't kick in. That could be one purpose of the new
	option. It isn't documented yet; I will seek feedback about its
	usefulness first.

compiler/modecheck_unify.m:
	Handle the three different kinds of right hand sides separately.
	This yields a small speedup, because now we don't test rhs_vars and
	rhs_functors (the common right hand sides) for a special case
	(goals containing "any" insts) that is applicable only to
	rhs_lambda_goals.

compiler/unique_modes.m:
	Don't traverse scopes that construct ground terms, since modes.m has
	already done everything that needs to be done.

compiler/det_analysis.m:
	Don't traverse scopes that construct ground terms, since modes.m has
	already done the needed work.

compiler/instmap.m:
	Add a new predicate for use by modes.m.

	Many predicate names in this module were quite uninformative; give them
	informative names.

compiler/polymorphism.m:
	If this pass invalidates the from_ground_term_construct invariants,
	then mark the relevant scope as from_ground_term_other.

	Delete two unused access predicates.

compiler/equiv_type_hlds.m:
	Don't traverse scopes that construct ground terms, since modes.m
	ensures that their instmap deltas do not contain typed insts, and
	thus the scope cannot contain types that need to be expanded.

	Convert some predicates to single clauses.

compiler/goal_form.m:
compiler/goal_util.m:
	In predicates that test goals for various properties, don't traverse
	scopes that construct ground terms when the outcome of the test
	is the same for all such scopes.

	Convert some predicates to single clauses.

compiler/simplify.m:
	Do not look for common structs in from_ground_term_construct scopes,
	both because this speeds up the compiler, and because retaining
	references to ground terms is in fact a pessimization, not an
	optimization. This is because (a) those references need to be stored in
	stack slots across calls, and (b) the C code generators ensure that
	the cells representing ground terms will be shared as needed.

	If all arms of a switch are from_ground_term_construct scopes,
	do not merge the instmap_deltas from those arms, since this is
	both time-consuming (even after the other changes in this diff)
	and extremely unlikely to improve the instmap_delta.

	Disable common_struct in from_ground_term_construct scopes,
	since for these scopes, it is actually a pessimization.

	Do not delete from_ground_term_construct scopes, since many
	compiler passes can now use them.

	Do some manual deforestation, break up some large predicates,
	and give better names to some.

compiler/liveness.m
	Special-case the handling from_ground_term_construct scopes. This
	allows us to traverse them just once instead of three times, and this
	traversal is simpler and faster than any of the three.

	In some traversals, we were switching on the goal type twice; once
	in e.g. detect_liveness_in_goal_2, and once by calling
	goal_expr_has_subgoals. Eliminate the double switching by merging
	the relevant predicates. (The double-switching structure was easier
	to work with before we had multi-cons-id switches.)

compiler/typecheck.m:
	Move a lookup after a test, so we don't have to do it if the test
	fails.

	Provide a specialized mode for a predicate. This should allow the
	compiler to eliminate an argument and a test in the common case.

	Note a possible chance for a speedup.

compiler/typecheck_info.m:
	Don't apply empty substitutions to the types of a possibly very large
	set of variables.

compiler/quantification.m:
	Don't quantify from_ground_term_construct scopes. They are created
	correctly quantified, and any compiler pass that invalidates that
	quantification also removes the from_ground_term_construct mark.

	Don't apply empty renamings to a possibly very large set of variables.

	Move the code for handling scopes to its own predicate, to avoid
	overwhelming the code that handles other kinds of goals. Even from
	this, factor out the renaming code, since it is needed only for
	some kinds of scopes.

	Make some predicate names better reflect what the predicate does.

compiler/pd_cost.m:
	For from_ground_term_construct scopes, instead of computing their cost
	by adding up the costs of the goals inside, make their cost a constant,
	since binding a variable to a static term takes constant time.

compiler/pd_info.m:
	Add prefixes on field names to avoid ambiguities.

compiler/add_heap_ops.m:
compiler/add_trail_ops.m:
compiler/closure_analysis.m:
compiler/constraint.m:
compiler/cse_detection.m:
compiler/dead_proc_elim.m:
compiler/deep_profiling.m:
compiler/deforest.m:
compiler/delay_construct.m:
compiler/delay_partial_inst.m:
compiler/dep_par_conj.m:
compiler/distance_granularity.m:
compiler/exception_analysis.m:
compiler/follow_code.m:
compiler/follow_vars.m:
compiler/format_call.m:
compiler/granularity.m:
compiler/higher_order.m:
compiler/implicit_parallelism.m:
compiler/inlining.m:
compiler/interval.m:
compiler/lambda.m:
compiler/lco.m:
compiler/live_vars.m:
compiler/loop_inv.m:
compiler/middle_rec.m:
compiler/mode_util.m:
compiler/parallel_to_plain_conj.m:
compiler/saved_vars.m:
compiler/stm_expand.m:
compiler/store_alloc.m:
compiler/stratify.m:
compiler/structure_reuse.direct.detect_garbage.m:
compiler/structure_reuse.lbu.m:
compiler/structure_sharing.analysis.m:
compiler/switch_detection.analysis.m:
compiler/trail_analysis.m:
compiler/term_pass1.m:
compiler/tupling.m:
compiler/unneeded_code.m:
compiler/untupling.m:
compiler/unused_args.m:
	These passes have nothing to do in from_ground_term_construct scopes,
	so don't traverse them.

	In some modules (e.g. dead_proc_elim), some traversals had to be kept.

	In loop_inv.m, replace a code structure that updated accumulators
	with functions (which prevented the natural use of state variables),
	that in lots of places reconstructed the term it had just
	deconstructed, and obscured the identical handling of different kinds
	of goals, with a structure based on predicates, state variables and
	shared code for different goal types where possible.

	In store_alloc.m, avoid some double switching on the same value.

	In stratify.m, unneeded_code.m and unused_args.m, rename predicates
	to avoid ambiguities.

compiler/goal_path.m:
compiler/goal_util.m:
compiler/implementation_defined_literals.m:
compiler/intermode.m:
compiler/mark_static_terms.m:
compiler/ml_code_gen.m:
compiler/mode_ordering.m:
compiler/ordering_mode_constraints.m:
compiler/prop_mode_constraints.m:
compiler/purity.m:
compiler/rbmm.actual_region_arguments.m:
compiler/rbmm.add_rbmm_goal_infos.m:
compiler/rbmm.condition_renaming.m:
compiler/rbmm.execution_path.m:
compiler/rbmm.region_transformation.m:
compiler/structure_reuse.direct.choose_reuse.m:
compiler/structure_reuse.indirect.m:
compiler/structure_reuse.lfu.m:
compiler/structure_reuse.versions.m:
compiler/term_const_build.m:
compiler/term_traversal.m:
compiler/unused_imports.m:
	Mark places where we cannot (yet) special case
	from_ground_term_construct scopes.

	In structure_reuse.lfu.m, turn nested if-then-elses into a switch in.

compiler/size_prof.m:
	Turn from_ground_term_construct scopes into from_ground_term_other
	scopes, since in term size profiling grades, we need to attach sizes to
	terms.

	Give predicates better names.

compiler/*.m:
	Minor changes to conform to the changes above.

compiler/make_hlds_passes.m:
	With -S, print statistics after the third pass over items, since
	this is the time-consuming one.

compiler/mercury_compile.m:
	Conform to the new names of some predicates.

	When declining to output a HLDS dump because it would be identical to
	the previous dump, don't confuse the user either by being silent about
	the decision, or by leaving an old dump laying around that could be
	mistaken for a new one.

tools/binary:
tools/binary_step:
	Bring these tools up to date.

compiler/Mmakefile:
	Add an int3s target for use by the new code in the tools. The
	Mmakefiles in the other directories with Mercury code already have
	such a target.

compiler/notes/allocation.html:
	Fix an out-of-date reference.

tests/debugger/polymorphic_ground_term.{m,inp,exp}:
	New test case to check whether liveness.m handles typeinfo liveness
	of ground terms correctly.

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

tests/debugger/polymorphic_output.{m,exp}:
	Fix tab/space mixup.
2008-12-23 01:38:03 +00:00
Peter Wang
05ccd776ef When converting lambdas into separate predicates, the non-local sets of
Estimated hours taken: 3
Branches: main

When converting lambdas into separate predicates, the non-local sets of
the procedure which contained the lambda may change.  However, the
compiler didn't recompute instmap deltas so that some non-local variables
might not appear in the instmap delta for the goal.

compiler/lambda.m:
	Recompute instmap deltas after requantifying the procedure.

tests/valid/Mmakefile:
tests/valid/lambda_instmap_bug2.m:
	Add test case.
2008-10-22 05:42:57 +00:00
Zoltan Somogyi
b000cb322e Provide compiler support for Software Transactional Memory through the new
Estimated hours taken: 80 by zs, and lots more by lmika
Branches: main

Provide compiler support for Software Transactional Memory through the new
atomic goal. This work was done by Leon Mika; I merely brought it up to date,
resolved conflicts, and cleaned up a few things. There are still several
aspects that are as yet incomplete.

library/ops.m:
	Add the operators needed for the syntax of atomic scopes.

library/stm_builtin.m:
	Add the builtin operations needed for the implementation of atomic
	goals.

compiler/hlds_goal.m:
	Add a new HLDS goal type, which represents an atomic goal and its
	possible fallbacks (in case an earlier goal throws an exception).

	Rename the predicate goal_is_atomic as goal_expr_has_subgoals,
	since now its old name would be misleading.

compiler/prog_data.m:
compiler/prog_item.m:
	Add a parse tree representation of the new kind of goal.

compiler/prog_io_goal.m:
	Parse the new kind of goal.

compiler/add_clause.m:
	Translate atomic goals from parse tree form to HLDS.

compiler/typecheck.m:
compiler/typecheck_errors.m:
	Do type checking of atomic goals.

compiler/modes.m:
	Do mode checking of atomic goals, and determine whether they are nested
	or not.

compiler/unique_modes.m:
	Do unique mode checking of atomic goals.

compiler/stm_expand.m:
	New module to expand atomic goals into sequences of simpler goals.

library/stm_builtin.m:
	Add the primitives needed by the transformation.

	Improve the existing debugging support.

mdbcomp/prim_data.m:
	Add utility functions to allow stm_expand.m to refer to modules in the
	library.

mdbcomp/program_representation.m:
	Expand the goal_path type to allow the representation of components of
	atomic goals.

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

compiler/transform_hlds.m:
	Include the new module in the compiler.

compiler/mercury_compile.m:
	Invoke the STM transformation.

compiler/hlds_module.m:
	Add an auxiliary counter used by the STM transformation.

compiler/hlds_pred.m:
	Add a new predicate origin: the STM transformation.

compiler/modules.m:
	Import the STM builtin module automatically if the module contains any
	atomic goals.

compiler/assertion.m:
compiler/bytecode_gen.m:
compiler/clause_to_proc.m:
compiler/code_gen.m:
compiler/code_info.m:
compiler/code_util.m:
compiler/constraint.m:
compiler/cse_detection.m:
compiler/deep_profiling.m:
compiler/code_util.m:
compiler/delay_construct.m:
compiler/delay_partial_inst.m:
compiler/dep_par_conj.m:
compiler/dependency_graph.m:
compiler/det_analysis.m:
compiler/det_report.m:
compiler/distance_granularity.m:
compiler/equiv_type_hlds.m:
compiler/erl_code_gen.m:
compiler/exception_analysis.m:
compiler/follow_code.m:
compiler/format_call.m:
compiler/goal_form.m:
compiler/goal_path.m:
compiler/goal_util.m:
compiler/granularity.m:
compiler/hlds_out.m:
compiler/implicit_parallelism.m:
compiler/inlining.m:
compiler/intermod.m:
compiler/lambda.m:
compiler/layout_out.m:
compiler/lco.m:
compiler/lookup_switch.m:
compiler/make_hlds_warn.m:
compiler/mark_static_terms.m:
compiler/mercury_to_mercury.m:
compiler/middle_rec.m:
compiler/ml_code_gen.m:
compiler/mode_constraint_robdd.m:
compiler/mode_constraints.m:
compiler/mode_errors.m:
compiler/mode_info.m:
compiler/mode_util.m:
compiler/ordering_mode_constraints.m:
compiler/pd_cost.m:
compiler/pd_util.m:
compiler/polymorphism.m:
compiler/post_typecheck.m:
compiler/prog_rep.m:
compiler/prog_type.m:
compiler/prop_mode_constraints.m:
compiler/rbmm.actual_region_arguments.m:
compiler/rbmm.add_rbmm_goal_info.m:
compiler/rbmm.condition_renaming.m:
compiler/rbmm.execution_path.m:
compiler/rbmm.points_to_analysis.m:
compiler/rbmm.region_transformation.m:
compiler/saved_vars.m:
compiler/simplify.m:
compiler/size_prog.m:
compiler/smm_common.m:
compiler/structure_reuse.direct.choose_reuse.m:
compiler/structure_reuse.direct.detect_garbage.m:
compiler/structure_reuse.indirect.m:
compiler/structure_reuse.lbu.m:
compiler/structure_reuse.lfu.m:
compiler/structure_reuse.versions.m:
compiler/structure_sharing.analysis.m:
compiler/switch_detection.m:
compiler/unused_imports.m:
compiler/granularity.m:
compiler/granularity.m:
	Conform to the changes above. Mostly this means handling the new
	kind of goal.

compiler/add_heap_ops.m:
compiler/add_trail_ops.m:
compiler/build_mode_constraints.m:
compiler/closure_analysis.m:
compiler/dead_proc_elim.m:
compiler/deforest.m:
compiler/follow_vars.m:
compiler/higher_order.m:
compiler/live_vars.m:
compiler/liveness.m:
compiler/loop_inv.m:
compiler/module_qual.m:
compiler/prog_util.m:
compiler/purity.m:
compiler/quantification.m:
compiler/store_alloc.m:
compiler/stratify.m:
compiler/tabling_analysis.m:
compiler/term_constr_build.m:
compiler/term_pass1.m:
compiler/term_traversal.m:
compiler/trailing_analysis.m:
	Conform to the changes above. Mostly this means handling the new
	kind of goal.

	Switch syntax from clauses to disj.

runtime/mercury_stm.[ch]:
	Implement the primitives needed by the STM transformation.

	Add more debugging support to the existing primitives.

library/term.m:
	Generalize get_term_context to work on terms of all kinds.
2008-02-27 07:23:57 +00:00
Mark Brown
7460aadbf8 Implement higher-order any' insts. Pred or func expressions with an any'
Estimated hours taken: 100
Branches: main

Implement higher-order `any' insts.  Pred or func expressions with an `any'
inst may bind non-local solver variables, but themselves must not be
called in a negated context.  (The existing ground pred and func expressions
may not bind non-local solver variables, but may be called in a negated
context.)

Higher-order `any' insts are specified by using `any_pred' and `any_func'
in place of `pred' and `func', respectively.

We implement these insts by adding a new field to the any/1 constructor of
mer_inst, which is identical to the ground_inst_info field of the ground/2
constructor.  Both are given the new type `ho_inst_info'.  We then relax the
locking of non-local variables in these pred and func expressions, and extend
call/N and apply/N to also accept the new insts (provided the variables are
not locked).

We also store the groundness (ho_ground or ho_any) of each lambda expression
in a unification, in a new field in the rhs_lambda_goal constructor.

NEWS:
	Mention the new feature.

compiler/prog_data.m:
	Rename the ground_inst_info type ho_inst_info, and update its
	documentation.

	Add the ho_inst_info field to the any constructor in mer_inst.

compiler/hlds_goal.m:
	Add the rhs_groundness field to rhs_lambda_goal in unify_rhs.

compiler/inst_match.m:
	Propagate inst matching into the pred_inst_infos of any insts,
	if they exist.

compiler/inst_util.m:
	Propagate abstract unification and inst merging into the
	pred_inst_infos of any insts, if they exist.  May use of this
	information when building ground, any, shared and mostly_unique
	versions of insts.

compiler/modecheck_call.m:
	Allow an `any' inst as the pred (func) argument to call/N (apply/N),
	but check that the variable is not locked.  If the variable is
	locked, report a mode error which suggests using the ground inst.
	(We could also suggest that the goal be made impure, but it is
	best to point users towards the pure approach.)

compiler/modecheck_unify.m:
	Relax the locking of non-locals when processing non-ground lambda
	goals.

	Update documentation.

compiler/mode_util.m:
	Propagate type information into the pred_inst_infos of any insts.

compiler/mode_errors.m:
	Change the purity error "lambda should be impure" to "lambda
	should be any", since this is better advice.  Also provide an
	example of correct syntax if the verbose errors option is given.

compiler/prog_io_goal.m:
	Parse the new kinds of expressions, returning the groundness along
	with the existing information about lambda expressions.

compiler/superhomogeneous.m:
	Use the above groundness when building the lambda unification.

compiler/prog_io_util.m:
	Parse the new kind of insts, filling in the new ho_inst_info field
	where appropriate.

compiler/polymorphism.m:
	Handle the new fields.  Assume that the shorthand form of lambda
	expressions always defines a ground inst -- if users want non-ground
	higher-order expressions they will need to use an explicit any_pred
	or any_func expression.

compiler/equiv_type_hlds.m:
	Replace equivalent types in the pred_inst_infos of `any' insts.

compiler/module_qual.m:
	Module qualify the pred_inst_infos of `any' insts.

compiler/recompilation.usage.m:
compiler/unused_imports.m:
	Look for items or imports used by insts in the pred_inst_infos of
	`any' insts.

compiler/hlds_out.m:
compiler/mercury_to_mercury.m:
	Output the new lambda expressions and insts in the correct format.

compiler/type_util.m:
	Treat all pred and func types as solver types.  (Effectively they
	are, since all such types can now have non-ground values, with
	call/N and apply/N acting as constraints.)

compiler/lambda.m:
	Pass the groundness value when building procedures for lambda
	expressions.  This is not currently required for anything.

doc/reference_manual.texi:
	Document the new feature, and update existing documentation on
	solver types and negated contexts.

tests/valid/Mmakefile:
tests/valid/ho_any_inst.m:
	New test case for some valid code using higher-order any insts.

tests/invalid/Mmakefile:
tests/invalid/ho_any_inst.err_exp:
tests/invalid/ho_any_inst.m:
	New test case for some illegal code.

tests/invalid/anys_in_negated_contexts.err_exp:
	Update expected error message for this test case.  We now report
	that the expression should be `any', rather than impure.

compiler/*.m:
	Handle the new fields.
2008-01-22 15:08:36 +00:00
Zoltan Somogyi
cc88711d63 Implement true multi-cons_id arm switches, i.e. switches in which we associate
Estimated hours taken: 40
Branches: main

Implement true multi-cons_id arm switches, i.e. switches in which we associate
more than one cons_id with a switch arm. Previously, for switches like this:

	(
		X = a,
		goal1
	;
		( X = b
		; X = c
		),
		goal2
	)

we duplicated goal2. With this diff, goal2 won't be duplicated. We still
duplicate goals when that is necessary, i.e. in cases which the inner
disjunction contains code other than a functor test on the switched-on var,
like this:

	(
		X = a,
		goal1
	;
		(
			X = b,
			goalb
		;
			X = c
			goalc
		),
		goal2
	)

For now, true multi-cons_id arm switches are supported only by the LLDS
backend. Supporting them on the MLDS backend is trickier, because some MLDS
target languages (e.g. Java) don't support the concept at all. So when
compiling to MLDS, we still duplicate the goal in switch detection (although
we could delay the duplication to just before code generation, if we wanted.)

compiler/options.m:
	Add an internal option that tells switch detection whether to look for
	multi-cons_id switch arms.

compiler/handle_options.m:
	Set this option based on the back end.

	Add a version of the "trans" dump level that doesn't print unification
	details.

compiler/hlds_goal.m:
	Extend the representation of switch cases to allow more than one
	cons_id for a switch arm.

	Add a type for representing switches that also includes tag information
	(for use by the backends).

compiler/hlds_data.m:
	For du types, record whether it is possible to speed up tests for one
	cons_id (e.g. cons) by testing for the other (nil) and negating the
	result. Recording this information once is faster than having
	unify_gen.m trying to compute it from scratch for every single
	tag test.

	Add a type for representing a cons_id together with its tag.

compiler/hlds_out.m:
	Print out the cheaper_tag_test information for types, and possibly
	several cons_ids for each switch arm.

	Add some utility predicates for describing switch arms in terms of
	which cons_ids they are for.

	Replace some booleans with purpose-specific types.

	Make hlds_out honor is documentation, and not print out detailed
	information about unifications (e.g. uniqueness and static allocation)
	unless the right character ('u') is present in the control string.

compiler/add_type.m:
	Fill in the information about cheaper tag tests when adding a du type.

compiler/switch_detection.m:
	Extend the switch detection algorithm to detect multi-cons_id switch
	arms.

	When entering a switch arm, update the instmap to reflect that the
	switched-on variable can now be bound only to the cons_ids that this
	switch arm is for. We now need to do this, because if the arm contains
	another switch on the same variable, computing the can_fail field of
	that switch correctly requires us to know this information.
	(Obviously, an arm for a single cons_id is unlikely to have switch on
	the same variable, and for arms for several cons_ids, we previously
	duplicated the arm and left the unification with the cons_id in each
	copy, and this unification allowed the correct handling of any later
	switches. However, the code of a multi-cons_id switch arm obviously
	cannot have a unification with each cons_id in it, which is why
	we now need to get the binding information from the switch itself.)

	Replace some booleans with purpose-specific types, and give some
	predicates better names.

compiler/instmap.m:
	Provide predicates for recording that a switched-on variable has
	one of several given cons_ids, for use at the starts of switch arms.

	Give some predicates better names.

compiler/modes.m:
	Provide predicates for updating the mode_info at the start of a
	multi-cons_id switch arm.

compiler/det_report.m:
	Handle multi-cons_id switch arms.

	Update the instmap when entering each switch arm, since this is needed
	to provide good (i.e. non-misleading) error messages when one switch on
	a variable exists inside another switch on the same variable.

	Since updating the instmap requires updating the module_info (since
	the new inst may require a new entry in an inst table), thread the
	det_info through as updateable state.

	Replace some multi-clause predicate definitions with single clauses,
	to make it easier to print the arguments in mdb.

	Fix some misleading variable names.

compiler/det_analysis.m:
	Update the instmap when entering each switch arm and thread the
	det_info through as updateable state, since the predicates we call
	in det_report.m require this.

compiler/det_util.m:
	Handle multi-cons_id switch arms.

	Rationalize the argument order of some access predicates.

compiler/switch_util.m:
	Change the parts of this module that deal with string and tag switches
	to optionally convert each arm to an arbitrary representation of the
	arm. In the LLDS backend, the conversion process generated code for
	the arm, and the arm's representation is the label at the start of
	this code. This way, we can duplicate the label without duplicating
	the code.

	Add a new part of this module that associates each cons_id with its
	tag, and (during the same pass) checks whether all the cons_ids are
	integers, and if so what are min and max of these integers (needed
	for dense switches). This scan is needed because the old way of making
	this test had single-cons_id switch arms as one of its basic
	assumptions, and doing it while adding tags to each case reduces
	the number of traversals required.

	Give better names to some predicates.

compiler/switch_case.m:
	New module to handle the tasks associated with managing multi-cons_id
	switch arms, including representing them for switch_util.m.

compiler/ll_backend.m:
	Include the new module.

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

compiler/llds.m:
	Change the computed goto instruction to take a list of maybe labels
	instead of a list of labels, with any missing labels meaning "not
	reached".

compiler/string_switch.m:
compiler/tag_switch.m:
	Reorganize the way these modules work. We can't generate the code of
	each arm in place anymore, since it is now possible for more than one
	cons_id to call for the execution of the same code. Instead, in
	string_switch.m, we generate the codes of all the arms all at once,
	and construct the hash index afterwards. (This approach simplifies
	the code significantly.)

	In tag switches (unlike string switches), we can get locality benefits
	if the code testing for a cons_id is close to the code for that
	cons_id, so we still try to put them next to each other when such
	a locality benefit is available.

	In both modules, the new approach uses a utility predicate in
	switch_case.m to actually generate the code of each switch arm,
	eliminating several copies the same code in the old versions of these
	modules.

	In tag_switch.m, don't create a local label that simply jumps to the
	code address do_not_reached. Previously, we had to do this for
	positions in jump tables that corresponded to cons_ids that the switch
	variable could not be bound to. With the change to llds.m, we now
	simply generate a "no" instead.

compiler/lookup_switch.m:
	Get the info about int switch limits from our caller; don't compute it
	here.

	Give some variables better names.

compiler/dense_switch.m:
	Generate the codes of the cases all at once, then assemble the table,
	duplicate the labels as needed. This separation of concerns allows
	significant simplifications.

	Pack up all the information shared between the predicate that detects
	whether a dense switch is appropriate and the predicate that actually
	generates the dense switch.

	Move some utility predicates to switch_util.

compiler/switch_gen.m:
	Delete the code for tagging cons_ids, since that functionality is now
	in switch_util.m.

	The old version of this module could call the code generator to produce
	(i.e. materialize) the switched-on variable repeatedly. We now produce
	the variable once, and do the switch on the resulting rval.

compiler/unify_gen.m:
	Use the information about cheaper tag tests in the type constructor's
	entry in the HLDS type table, instead of trying to recompute it
	every time.

	Provide the predicates switch_gen.m now needs to perform tag tests
	on rvals, as opposed to variables, and against possible more than one
	cons_id.

	Allow the caller to provide the tag corresponding to the cons_id(s)
	in tag tests, since when we are generating code for switches, the
	required computations have already been done.

	Factor out some code to make all this possible.

	Give better names to some predicates.

compiler/code_info.m:
	Provide some utility predicates for the new code in other modules.
	Give better names to some existing predicates.

compiler/hlds_code_util.m:
	Rationalize the argument order of some predicates.

	Replace some multi-clause predicate definitions with single clauses,
	to make it easier to print the arguments in mdb.

compiler/accumulator.m:
compiler/add_heap_ops.m:
compiler/add_pragma.m:
compiler/add_trail_ops.m:
compiler/assertion.m:
compiler/build_mode_constraints.m:
compiler/check_typeclass.m:
compiler/closure_analysis.m:
compiler/code_util.m:
compiler/constraint.m:
compiler/cse_detection.m:
compiler/dead_proc_elim.m:
compiler/deep_profiling.m:
compiler/deforest.m:
compiler/delay_construct.m:
compiler/delay_partial_inst.m:
compiler/dep_par_conj.m:
compiler/distance_granularity.m:
compiler/dupproc.m:
compiler/equiv_type_hlds.m:
compiler/erl_code_gen.m:
compiler/exception_analysis.m:
compiler/export.m:
compiler/follow_code.m:
compiler/follow_vars.m:
compiler/foreign.m:
compiler/format_call.m:
compiler/frameopt.m:
compiler/goal_form.m:
compiler/goal_path.m:
compiler/goal_util.m:
compiler/granularity.m:
compiler/hhf.m:
compiler/higher_order.m:
compiler/implicit_parallelism.m:
compiler/inlining.m:
compiler/inst_check.m:
compiler/intermod.m:
compiler/interval.m:
compiler/lambda.m:
compiler/lambda.m:
compiler/lambda.m:
compiler/lco.m:
compiler/live_vars.m:
compiler/livemap.m:
compiler/liveness.m:
compiler/llds_out.m:
compiler/llds_to_x86_64.m:
compiler/loop_inv.m:
compiler/make_hlds_warn.m:
compiler/mark_static_terms.m:
compiler/middle_rec.m:
compiler/ml_tag_switch.m:
compiler/ml_type_gen.m:
compiler/ml_unify_gen.m:
compiler/mode_constraints.m:
compiler/mode_errors.m:
compiler/mode_util.m:
compiler/opt_debug.m:
compiler/opt_util.m:
compiler/pd_cost.m:
compiler/pd_into.m:
compiler/pd_util.m:
compiler/peephole.m:
compiler/polymorphism.m:
compiler/post_term_analysis.m:
compiler/post_typecheck.m:
compiler/purity.m:
compiler/quantification.m:
compiler/rbmm.actual_region_arguments.m:
compiler/rbmm.add_rbmm_goal_infos.m:
compiler/rbmm.condition_renaming.m:
compiler/rbmm.execution_paths.m:
compiler/rbmm.points_to_analysis.m:
compiler/rbmm.region_transformation.m:
compiler/recompilation.usage.m:
compiler/saved_vars.m:
compiler/simplify.m:
compiler/size_prof.m:
compiler/ssdebug.m:
compiler/store_alloc.m:
compiler/stratify.m:
compiler/structure_reuse.direct.choose_reuse.m:
compiler/structure_reuse.indirect.m:
compiler/structure_reuse.lbu.m:
compiler/structure_reuse.lfu.m:
compiler/structure_reuse.versions.m:
compiler/structure_sharing.analysis.m:
compiler/table_gen.m:
compiler/tabling_analysis.m:
compiler/term_constr_build.m:
compiler/term_norm.m:
compiler/term_pass1.m:
compiler/term_traversal.m:
compiler/trailing_analysis.m:
compiler/transform_llds.m:
compiler/tupling.m:
compiler/type_ctor_info.m:
compiler/type_util.m:
compiler/unify_proc.m:
compiler/unique_modes.m:
compiler/unneeded_code.m:
compiler/untupling.m:
compiler/unused_args.m:
compiler/unused_imports.m:
compiler/xml_documentation.m:
	Make the changes necessary to conform to the changes above, principally
	to handle multi-cons_id arm switches.

compiler/ml_string_switch.m:
	Make the changes necessary to conform to the changes above, principally
	to handle multi-cons_id arm switches.

	Give some predicates better names.

compiler/dependency_graph.m:
	Make the changes necessary to conform to the changes above, principally
	to handle multi-cons_id arm switches. Change the order of arguments
	of some predicates to make this easier.

compiler/bytecode.m:
compiler/bytecode_data.m:
compiler/bytecode_gen.m:
	Make the changes necessary to conform to the changes above, principally
	to handle multi-cons_id arm switches. (The bytecode interpreter
	has not been updated.)

compiler/prog_rep.m:
mdbcomp/program_representation.m:
	Change the byte sequence representation of goals to allow switch arms
	with more than one cons_id. compiler/prog_rep.m now writes out the
	updated representation, while mdbcomp/program_representation.m reads in
	the updated representation.

deep_profiler/mdbprof_procrep.m:
	Conform to the updated program representation.

tools/binary:
	Fix a bug: if the -D option was given, the stage 2 directory wasn't
	being initialized.

	Abort if users try to give that option more than once.

compiler/Mercury.options:
	Work around bug #32 in Mantis.
2007-12-30 08:24:23 +00:00
Zoltan Somogyi
672f77c4ec Add a new compiler option. --inform-ite-instead-of-switch.
Estimated hours taken: 20
Branches: main

Add a new compiler option. --inform-ite-instead-of-switch. If this is enabled,
the compiler will generate informational messages about if-then-elses that
it thinks should be converted to switches for the sake of program reliability.

Act on the output generated by this option.

compiler/simplify.m:
	Implement the new option.

	Fix an old bug that could cause us to generate warnings about code
	that was OK in one duplicated copy but not in another (where a switch
	arm's code is duplicated due to the case being selected for more than
	one cons_id).

compiler/options.m:
	Add the new option.

	Add a way to test for the bug fix in simplify.

doc/user_guide.texi:
	Document the new option.

NEWS:
	Mention the new option.

library/*.m:
mdbcomp/*.m:
browser/*.m:
compiler/*.m:
deep_profiler/*.m:
	Convert if-then-elses to switches at most of the sites suggested by the
	new option. At the remaining sites, switching to switches would have
	nontrivial downsides. This typically happens with the switched-on type
	has many functors, and we treat one or two specially (e.g. cons/2 in
	the cons_id type).

	Perform misc cleanups in the vicinity of the if-then-else to switch
	conversions.

	In a few cases, improve the error messages generated.

compiler/accumulator.m:
compiler/hlds_goal.m:
	(Rename and) move insts for particular kinds of goal from
	accumulator.m to hlds_goal.m, to allow them to be used in other
	modules. Using these insts allowed us to eliminate some if-then-elses
	entirely.

compiler/exprn_aux.m:
	Instead of fixing some if-then-elses, delete the predicates containing
	them, since they aren't used, and (as pointed out by the new option)
	would need considerable other fixing if they were ever needed again.

compiler/lp_rational.m:
	Add prefixes to the names of the function symbols on some types,
	since without those prefixes, it was hard to figure out what type
	the switch corresponding to an old if-then-else was switching on.

tests/invalid/reserve_tag.err_exp:
	Expect a new, improved error message.
2007-11-23 07:36:01 +00:00
Peter Wang
d883fb772e Fix a bug in the following optimisation of model_non lambdas:
Estimated hours taken: 1
Branches: main

Fix a bug in the following optimisation of model_non lambdas:

        % Optimize a special case: replace
        %   `(pred(Y1, Y2, ...) is Detism :-
        %       p(X1, X2, ..., Y1, Y2, ...))'
        % where `p' has determinism `Detism' with
        %   `p(X1, X2, ...)'
        %

For the LLDS back-end the optimisation was also applied when `p' is model_det
but the lambda is model_non.  However it was incorrectly applied for the
erlang grade as well.

compiler/lambda.m:
	Don't apply the optimisation in the case above.

tests/hard_coded/Mmakefile:
tests/hard_coded/nondet_lambda.exp:
tests/hard_coded/nondet_lambda.m:
	Add a test case.
2007-09-04 03:12:21 +00:00
Zoltan Somogyi
168f531867 Add new fields to the goal_info structure for region based memory management.
Estimated hours taken: 4
Branches: main

Add new fields to the goal_info structure for region based memory management.
The fields are currently unused, but (a) Quan will add the code to fill them
in, and then (b) I will modify the code generator to use the filled in fields.

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

	Group all the procedures that access goal_info components together.
	Some of the getters were predicates while some were functions, so
	this diff changes them all to be functions. (The setters remain
	predicates.)

compiler/*.m:
	Trivial changes to conform to the change in hlds_goal.m.

	In simplify.m, break up a huge (800+ line) predicate into smaller
	pieces.
2007-08-07 07:10:09 +00:00
Zoltan Somogyi
27aaaf412c Fix the failure of the invalid/modes_erroneous test case, whose symptom was
Estimated hours taken: 5
Branches: main

Fix the failure of the invalid/modes_erroneous test case, whose symptom was
an error message about a "mode error in unification of `X' and `X'".
The root cause of the problem was that the renaming of head variables
computed by headvar_names.m was being applied too early, during typechecking.
The fix is to apply it after the frontend (all the passes that can generate
error messages).

To avoid slowdowns from larger pred_infos, this diff also moves the least
frequently used fields of pred_infos to a subterm. (Proc_infos already had
a subterm.) This leads to an almost 3% speedup.

compiler/headvar_names.m:
	Store the renaming instead of applying it.

compiler/simplify.m:
	Apply the renaming in invocations after the front end, since doing so
	may allow some excess assignments to be eliminated.

compiler/hlds_pred.m:
	Add fields to pred_infos and proc_infos for the renaming.

	Move the least frequently used fields of pred_infos into a
	pred_sub_info.

	Some fields of pred_infos were being accessed using predicates
	that did not follow our naming conventions, and some were accessed
	using field access functions that are now inappropriate; fix them all.

	Require the caller to provide the renaming when creating new pred_infos
	and proc_infos. This is to force the compiler components that do this
	to propagate the renaming fields of the original predicates and/or
	procedures to their modified versions.

	Convert that some old code that used if-then-elses to use switches
	instead.

compiler/hlds_out.m:
	Write out the new pred_info and proc_info fields.

compiler/*.m:
	Conform to the changes in hlds_pred.m.

compiler/hlds_clauses.m:
	Avoid ambiguity by giving a prefix to the fields of the clauses_info
	type.

tests/invalid/ho_type_mode_bug.err_exp:
tests/invalid/merge_ground_any.err_exp:
	Don't expect error messages about "X = X" anymore.
2007-05-17 03:53:13 +00:00
Zoltan Somogyi
b56885be93 Fix a bug that caused bootchecks with --optimize-constructor-last-call to fail.
Estimated hours taken: 12
Branches: main

Fix a bug that caused bootchecks with --optimize-constructor-last-call to fail.

The problem was not in lco.m, but in follow_code.m. In some cases,
(specifically, the LCMC version of insert_2 in sparse_bitset.m),
follow_code.m moved an impure goal (store_at_ref) into the arms of an
if-then-else without marking those arms, or the if-then-else, as impure.
The next pass, simplify, then deleted the entire if-then-else, since it
had no outputs. (The store_at_ref that originally appeared after the
if-then-else was the only consumer of its only output.)

The fix is to get follow_code.m to make branched control structures such as
if-then-elses, as well as their arms, semipure or impure if a goal being moved
into them is semipure or impure, or if they came from an semipure or impure
conjunction.

Improve the optimization of the LCMC version of sparse_bitset.insert_2, which
had a foreign_proc invocation of bits_per_int in it: replace such invocations
with a unification of the bits_per_int constant if not cross compiling.

Add a new option, --optimize-constructor-last-call-null. When set, LCMC will
assign NULLs to the fields not yet filled in, to avoid any junk happens to be
there from being followed by the garbage collector's mark phase.

This diff also makes several other changes that helped me to track down
the bug above.

compiler/follow_code.m:
	Make the fix described above.

	Delete all the provisions for --prev-code; it won't be implemented.

	Don't export a predicate that is not now used anywhere else.

compiler/simplify.m:
	Make the optimization described above.

compiler/lco.m:
	Make sure that the LCMC specialized procedure is a predicate, not a
	function: having a function with the mode LCMC_insert_2(in, in) = in
	looks wrong.

	To avoid name collisions when a function and a predicate with the same
	name and arity have LCMC applied to them, include the predicate vs
	function status of the original procedure included in the name of the
	new procedure.

	Update the sym_name of calls to LCMC variants, not just the pred_id,
	because without that, the HLDS dump looks misleading.

compiler/pred_table.m:
	Don't have optimizations like LCMC insert new predicates at the front
	of the list of predicates. Maintain the list of predicates in the
	module as a two part list, to allow efficient addition of new pred_ids
	at the (logical) end without using O(N^2) algorithms. Having predicates
	in chronological order makes it easier to look at HLDS dumps and
	.c files.

compiler/hlds_module.m:
	Make module_info_predids return a module_info that is physically
	updated though logically unchanged.

compiler/options.m:
	Add --optimize-constructor-last-call-null.

	Make the options --dump-hlds-pred-id, --debug-opt-pred-id and
	--debug-opt-pred-name into accumulating options, to allow the user
	to specify more than one predicate to be dumped (e.g. insert_2 and
	its LCMC variant).

	Delete --prev-code.

doc/user_guide.texi:
	Document the changes in options.m.

compiler/code_info.m:
	Record the value of --optimize-constructor-last-call-null in the
	code_info, to avoid lookup at every cell construction.

compiler/unify_gen.m:
compiler/var_locn.m:
	When deciding whether a cell can be static or not, make sure that
	we never make static a cell that has some fields initialized with
	dummy zeros, to be filled in for real later.

compiler/hlds_out.m:
	For goals that are semipure or impure, note this fact. This info was
	lost when I changed the representation of impurity from markers to a
	field.

mdbcomp/prim_data.m:
	Rename some ambiguous function symbols.

compiler/intermod.m:
compiler/trans_opt.m:
	Rename the main predicates (and some function symbols) of these modules
	to avoid ambiguity and to make them more expressive.

compiler/llds.m:
	Don't print line numbers for foreign_code fragments if the user has
	specified --no-line-numbers.

compiler/make.dependencies.m:
compiler/mercury_to_mercury.m:
compiler/recompilation.usage.m:
	Don't use io.write to write out information to files we may need to
	parse again, because this is vulnerable to changes to the names of
	function symbols (e.g. the one to mdbcomp/prim_data.m).

	The compiler still contains some uses of io.write, but they are
	for debugging. I added an item to the todo list of the one exception,
	ilasm.m.

compiler/recompilation.m:
	Rename a misleading function symbol name.

compiler/parse_tree.m:
	Don't import recompilation.m here. It is not needed (all the components
	of parse_tree that need recompilation.m already import it themselves),
	and deleting the import avoids recompiling almost everything when
	recompilation.m changes.

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

compiler/*.m:
browser/*.m:
slice/*.m:
	Conform to the change to mdbcomp.

library/sparse_bitset.m:
	Use some better variable names.
2007-01-19 07:05:06 +00:00
Zoltan Somogyi
ba93a52fe7 This diff changes a few types from being defined as equivalent to a pair
Estimated hours taken: 10
Branches: main

This diff changes a few types from being defined as equivalent to a pair
to being discriminated union types with their own function symbol. This
was motivated by an error message (one of many, but the one that broke
the camel's back) about "-" being used in an ambiguous manner. It will
reduce the number of such messages in the future, and will make compiler
data structures easier to inspect in the debugger.

The most important type changed by far is hlds_goal, whose function symbol
is now "hlds_goal". Second and third in importance are llds.instruction
(function symbol "llds_instr") and prog_item.m's item_and_context (function
symbol "item_and_context"). There are some others as well.

In several places, I rearranged predicates to factor the deconstruction of
goals into hlds_goal_expr and hlds_goal_into out of each clause into a single
point. In many places, I changed variable names that used "Goal" to refer
to just hlds_goal_exprs to use "GoalExpr" instead. I also changed variable
names that used "Item" to refer to item_and_contexts to use "ItemAndContext"
instead. This should make reading such code less confusing.

I renamed some function symbols and predicates to avoid ambiguities.

I only made one algorithmic change (at least intentionally).
In assertion.m, comparing two goals for equality now ignores goal_infos
for all kinds of goals, whereas previously it ignored them for most kinds
of goals, but for shorthand goals it was insisting on them being equal.
This seemed to me to be a bug. Pete, can you confirm this?
2007-01-06 09:23:59 +00:00
Simon Taylor
e972b1bb3d This module was setting each predicate's class context to the
Estimated hours taken: 6
Branches: main

compiler/lambda.m:
        This module was setting each predicate's class context to the
        class context of the last processed lambda goal in that predicate.
        This didn't cause any serious failures (that I know of), but it
        caused higher_order.m to miss opportunities for type class
        specialization in a streamified version of io.write.
2006-12-14 05:31:30 +00:00
Julien Fischer
ceabef6925 Replace an if-then-elses with switches.
Estimated hours taken: 0.1
Branches: main

compiler/lambda.m:
	Replace an if-then-elses with switches.

	Fix some formatting.
2006-12-12 04:23:20 +00:00
Zoltan Somogyi
45fd0daf5a Implement some of Mark's wish list for making user events more useful.
Estimated hours taken: 20
Branches: main

Implement some of Mark's wish list for making user events more useful.

1. When executing "print *" in mdb, we used to print both the values of all
   attributes and the values of all live variables. Since some attributes'
   values were given directly by live variables, this lead to some things being
   printed twice. This diff eliminates this duplication.

2. At user events, we now print the name of the event. Whether we print the
   other stuff we also print at events (the predicate containing the event,
   and its source location) is now controlled by a new mdb command,
   "user_event_context".

3. We would like different solvers to be compilable independently of one
   another. This means that neither solver's event set should depend on the
   existence of the events needed by the other solvers. This diff therefore
   eliminates the requirement that all modules of the program be compiled with
   the same event set specification. Instead, a program may contain modules
   that were compiled with different event sets. Each event set is named;
   the new requirement is that different named event sets may coexist in the
   program (each being used to compile some modules), but two event sets with
   the same name must be identical in all other respects as well (we need this
   requirement to prevent inconsistencies arising between different versions of
   the same event set).

4. We now generate user events even from modules compiled with --trace shallow.
   The problem here is that user events can occur in procedures that do not
   get caller events and whose ancestors may not get caller events either.
   Yet these procedures must still pass on debugger information such as call
   sequence numbers and the call depth to the predicate with the user event.
   This diff therefore decouples the generation of code for this basic debugger
   infrastructure information from the generation of call events by inventing
   two new trace levels, settable by the compiler only (i.e. not from the
   command line). The trace level "basic_user" is for procedures containing a
   user event whose trace level (in a shallow traced module) would otherwise be
   "none". The trace level "basic" is for procedures not containing a user
   event but which nevertheless may need to transmit information (e.g. depth)
   to a user event. For the foreseeable future, this means that shallow traced
   modules containing user events will have some debugging overhead compiled
   into *all* their procedures.

runtime/mercury_stack_layout.h:
	Add a new field to MR_UserEvent structures, giving the HLDS number of
	the variable representing each attribute.

	Add a new field to module layout structures, giving the name of the
	event set (if any) the module was compiled with.

	Add the new trace levels to the MR_TraceLevel type.

	Update the current layout structure version number.

runtime/mercury_stack_trace.[ch]:
	Allow the printing of the containing predicate's name and/or the
	filename/linenumber context to be turned off when printing contexts.
	Factor out some of the code involved in this printing.

	Give a bunch of variables better names.

	Rename a type to get rid of unnecessary underscores.

compiler/prog_data.m:
compiler/prog_event.m:
	Include the event set name in the information we have about the event
	set.

compiler/simplify.m:
	Mark each procedure and each module that contains user events
	as containing user events.

	Use the same technique to mark each procedure that contains parallel
	conjunctions as containing parallel conjunctions, instead of marking
	the predicate containing the procedure. (Switch detection may eliminate
	arbitrary goals, including parallel conjunctions, from switch arms
	that are unreachable due to initial insts, and in any case we want to
	handle the procedures of a predicate independently from each other
	after mode analysis.)

	Also, change the code handling generic calls to switch on the generic
	call kind, and factor out some common code.

compiler/hlds_module.m:
compiler/hlds_pred.m:
	Provide slots in the proc_info and the module_info for the information
	gathered by simplify.

compiler/trace_params.m:
	Implement the new trace levels described above. This required changing
	the signature of some of the predicates of this module.

compiler/code_info.m:
	Record whether the compiler generated any trace events. We need to know
	this, because if it did, then we must generate a proc layout structure
	for it.

compiler/proc_gen.m:
	Act on the information recorded by code_info.m.

	Factor out the code for generating the call event and its layout
	structure, since the conditions for generating this event have changed.

compiler/continuation_info.m:
compiler/call_gen.m:
	For each user event, record the id of the variables corresponding to
	each argument of a user event.

compiler/layout.m:
compiler/layout_out.m:
compiler/stack_layout.m:
	Generate the new field (giving the HLDS variable number of each
	attribute) in user event structures, and the new field (event set name)
	in module layout structures.

	Allow the call event's layout structure to be missing. This is needed
	for user events in shallow traced modules.

compiler/options.m:
compiler/handle_options.m:
compiler/mercury_compiler.m:
	Rename the option for specifying event sets from --event-spec-file-name
	to --event-set-file-name, since it specifies only one event set, not
	all events.

compiler/jumpopt.m:
	Give some predicates better names.

compiler/dep_par_conj.m:
compiler/deforest.m:
compiler/granularity.m:
compiler/hlds_out.m:
compiler/inlining.m:
compiler/intermod.m:
compiler/lambda.m:
compiler/liveness.m:
compiler/modes.m:
compiler/opt_debug.m:
compiler/optimize.m:
compiler/size_proc.m:
compiler/stack_alloc.m:
compiler/store_alloc.m:
compiler/table_gen.m:
compiler/trace_gen.m:
compiler/typecheck.m:
	Conform to the changes above.

doc/mdb_categories:
	Mention the new mdb command.

doc/user_guide.texi:
	Update the documentation of user events to account for the changes
	above.

trace/mercury_event_parser.y:
trace/mercury_event_scanner.l:
	Modify the grammar for event set specifications to a name for the
	event set.

trace/mercury_event_spec.[ch]:
	Instead of recording information about event sets internally
	in this module, return a representation of each event set read in
	to the callers, for them to do with as they please.

	Include the event set name when we print the Mercury term for
	compiler/prog_event.m.

trace/mercury_trace.c:
	Do not assume that every procedure that contains an event contains a
	call event (and hence a call event layout structure), since that
	is not true anymore.

trace/mercury_trace_cmd_parameter.[ch]:
	Implement the new mdb command "user_event_context".

trace/mercury_trace_cmd_internal.[ch]:
	Include "user_event_context" in the list of mdb commands.

	Print the user event name at user events. Let the current setting
	of the user_event_context mdb command determine what else to print
	at such events.

	Instead of reading in one event set on initialization, read in
	all event sets that occur in the program.

trace/mercury_trace_tables.[ch]:
	Allow the gathering of information for more than one event set
	from the modules of the program.

trace/mercury_trace_vars.[ch]:
	For each attribute value of a user event, record what the HLDS variable
	number of the attribute is. When printing all variables at an event,
	mark the variable numbers of printed attributes as being printed
	already, causing the variable with the same number not to be printed.

	Include the name of the variable (if it has one) in the description
	of an attribute. Without this, users may wonder why the value of the
	variable wasn't printed.

trace/mercury_trace_cmd_browsing.[ch]:
	Pass the current setting of the user_event_context mdb command to
	runtime/mercury_stack_trace.c when printing the context of an event.

tests/debugger/user_event_shallow.{m,inp,exp}:
	New test case to test the new functionality. This test case is the same
	as the user_event test case, but it is compiled with shallow tracing,
	and its mdb input exercises the user_event_context mdb command.

tests/debugger/user_event_spec:
tests/invalid/invalid_event_spec:
	Update these event set spec files by adding an event set name.

tests/debugger/Mmakefile:
tests/debugger/Mercury.options:
	Enable the new test case.

tests/debugger/user_event.exp:
	Update the expected output of the old user event test case, which now
	prints event names, but doesn't print attribute values twice.

tests/debugger/completion.exp:
	Expect the new "user_event_context" mdb command in the command list.

tests/debugger/mdb_command_test.inp:
	Test the existence of the documentation for the new mdb command.

tests/invalid/Mercury.options:
	Conform to the name change of the --event-spec-file-name option.
2006-12-05 03:51:22 +00:00
Julien Fischer
b4c3bb1387 Clean up in unused module imports in the Mercury system detected
Estimated hours taken: 3
Branches: main

Clean up in unused module imports in the Mercury system detected
by --warn-unused-imports.

analysis/*.m:
browser/*.m:
deep_profiler/*.m:
compiler/*.m:
library/*.m:
mdbcomp/*.m:
profiler/*.m:
slice/*.m:
	Remove unused module imports.

	Fix some minor departures from our coding standards.

analysis/Mercury.options:
browser/Mercury.options:
deep_profiler/Mercury.options:
compiler/Mercury.options:
library/Mercury.options:
mdbcomp/Mercury.options:
profiler/Mercury.options:
slice/Mercury.options:
	Set --no-warn-unused-imports for those modules that are used as
	packages or otherwise break --warn-unused-imports, e.g. because they
	contain predicates with both foreign and Mercury clauses and some of
	the imports only depend on the latter.
2006-12-01 15:04:40 +00:00
Zoltan Somogyi
f9cac21e3e Get rid of a bunch more ambiguities by renaming predicates, mostly
Estimated hours taken: 8
Branches: main

Get rid of a bunch more ambiguities by renaming predicates, mostly
in polymorphism.m, {abstract,build,ordering}_mode_constraints.m, prog_type.m,
and opt_debug.m in the compiler directory and term_io.m, term.m, parser.m,
and string.m in the library.

In some cases, when the library and the compiler defined the same predicate
with the same code, delete the compiler's copy and give it access to the
library's definition by exporting the relevant predicate (in the undocumented
part of the library module's interface).

NEWS:
	Mention that the names of some library functions have changed.

library/*.m:
compiler/*.m:
mdbcomp/*.m:
browser/*.m:
	Make the changes mentioned above, and conform to them.

test/general/string_test.m:
test/hard_coded/string_strip.m:
test/hard_coded/string_strip.exp:
	Conform to the above changes.
2006-09-20 09:42:28 +00:00
Zoltan Somogyi
00741b0162 This diff contains no algorithmic changes.
Estimated hours taken: 6
Branches: main

This diff contains no algorithmic changes. It merely renames apart a bunch more
function symbols to reduce ambiguity.

After this diff, the summary line from the mdb command "ambiguity -f" is

	Total: 351 names used 975 times, maximum 31, average: 2.78

browser/*.m:
compiler/*.m:
	Rename function symbols to eliminate ambiguities.

tests/debugger/declarative/dependency.exp:
tests/debugger/declarative/dependency2.exp:
	Update the expected out where some internal function symbol names
	appear in the output of the debugger. (This output is meant for
	implementors only.)
2006-08-22 05:04:29 +00:00
Zoltan Somogyi
2b2f3d3cbe This diff contains no algorithmic changes.
Estimated hours taken: 8
Branches: main

This diff contains no algorithmic changes. It merely renames apart a bunch of
function symbols to reduce ambiguity. Basically I went through prog_data.m,
prog_item.m, hlds_data.m, hlds_goal.m and hlds_pred.m looking for type
definitions containing function symbol names that were either language
"keywords" (e.g. "terminates", which is an annotation on foreign_procs),
used with slightly different meanings in several types (e.g. "sym"),
or both (e.g. "call"). When I found such type definitions, I changed the
names of the function symbols, usually by adding a prefix or suffix
indicating the type to all function symbols of the type. For example,
the old function symbol "foreign_proc" in type "pragma_type" is now named
"pragma_foreign_proc", and the names of all other function symbols in that
type also start with "pragma_".

All of this should yield simpler compiler error messages when we make mistakes,
and will make it more likely that looking up a function symbol using a tags
file will take you to the actual definition of the relevant instance of that
function symbol. However, the most important benefit is the increase in
the readability of unfamiliar code; the reader won't have to emulate the
compiler's type ambiguity resolution algorithm (which in many cases used to
require distinguishing between f/14 and f/15 by counting the arguments,
e.g. for "pred_or_func").

compiler/prog_data.m:
compiler/prog_item.m:
compiler/hlds_data.m:
compiler/hlds_goal.m:
compiler/hlds_pred.m:
	Rename function symbols as explained above.

compiler/*.m:
	Conform to the function symbol renames.

	In some cases, rename other function symbols as well.

	Minor style fixes, e.g. replace if-then-elses with switches,
	or simple det predicates with functions.
2006-08-20 08:21:36 +00:00
Peter Wang
0f5c482859 This patch reduces the amount of time spent running the dependent parallel
Estimated hours taken: 3
Branches: main

This patch reduces the amount of time spent running the dependent parallel
conjunction transformation by only running it on predicates which contain
(or could contain) parallel conjunctions.

compiler/hlds_out.m:
compiler/hlds_pred.m:
compiler/intermod.m:
compiler/size_prof.m:
compiler/table_gen.m:
	Add the marker `may_have_parallel_conj'.

compiler/simplify.m:
	When we come across a parallel conjunction during the simplification
	of a procedure, add the marker `may_have_parallel_conj' for the
	pred_info of that procedure.

compiler/dep_par_conj.m:
	Check that a predicate has the `may_have_parallel_conj' marker before
	running the dependent parallel conjunction transformation on the
	procedures of that predicate.

compiler/deforest.m:
compiler/inlining.m:
compiler/lambda.m:
	Preserve the `may_have_parallel_conj' marker in derived procedures.
2006-08-11 04:17:16 +00:00
Julien Fischer
e12ca34b2a Fix a bug reported by Peter Hawkins. The problem occurred with switches with
Estimated hours taken: 6
Branches: main, release

Fix a bug reported by Peter Hawkins.  The problem occurred with switches with
multiple arms that shared code.   Switch detection expands such arms by making
copies of the shared code.  Requantification then renames the variables in
these copies apart, but the new variables are not being entered into the RTTI
varmaps.   This leads to an assertion failure.

compiler/quantification.m:
 	Update the RTTI varmaps after renaming apart.  Failing to add any
 	freshly introduced variables into the RTTI varmaps makes them
 	inconsistent.

compiler/add_clause.m:
compiler/add_pragma.m:
compiler/cse_detection.m:
compiler/equiv_type_hlds.m:
compiler/follow_code.m:
compiler/hlds_clauses.m:
compiler/hlds_pred.m:
compiler/hlds_rtti.m:
compiler/lambda.m:
compiler/mode_constraints.m:
compiler/pd_util.m:
compiler/polymorphism.m:
compiler/saved_vars.m:
compiler/simplify.m:
compiler/size_prof.m:
compiler/tupling.m:
compiler/unify_proc.m:
compiler/unneeded_code.m:
compiler/unused_args.m:
 	Conform to the above change.

 	Minor formatting fixes.

tests/valid/Mmakefile:
tests/valid/hawkins_switch_bug.m:
 	Test case for the above.
2006-08-04 10:51:22 +00:00
Julien Fischer
aeeedd2c13 Standardize formatting of comments at the beginning of modules.
compiler/*.m:
	Standardize formatting of comments at the beginning of modules.
2006-07-31 08:32:11 +00:00
Zoltan Somogyi
9d23d8e2e7 Implement the trace goal construct we discussed, for now for the LLDS backends
Estimated hours taken: 70
Branches: main

Implement the trace goal construct we discussed, for now for the LLDS backends
only.

Since the syntax of trace goals is non-trivial, useful feedback on syntax
errors inside trace goal attributes is essential. With the previous setup, this
wasn't possible, since the code that turned terms into parse tree goals turned
*all* terms into goals; it couldn't recognize any errors, sweeping them under
the rug as calls. This diff changes that. Now, if this code recognizes a
keyword that indicates a particular construct, it insists on the rest of the
code following the syntax required for that construct, and returns error
messages if it doesn't.

We handle the trace goal attributes that specify state variables to be threaded
through the trace goal (either the I/O state or a mutable variable) in
add_clause.m, at the point at which we transform the list of items to the HLDS.
We handle the compile-time condition on trace goals in the invocation of
simplify at the end of semantics analysis, by eliminating the goal if the
compile-time condition isn't met. We handle run-time conditions on trace goals
partially in the same invocation of simplify: we transform trace goals with
runtime conditions into an if-then-else with the trace goal as the then part
and `true' as the else part, the condition being a foreign_proc that is handled
specially by the code generator, that special handling being to replace
the actual code of the foreign_proc (which is a dummy) with the evaluation of
the runtime condition.

Since these changes require significant changes to some of our key data
structures, I took the liberty of doing some renaming of function symbols
at the same time to avoid using ambiguities with respect to language keywords.

library/ops.m:
	Add "trace" as an operator.

compiler/prog_data.m:
	Define data types to represent the various attributes of trace goals.

	Rename some function symbols to avoid ambiguities.

compiler/prog_item.m:
	Extend the parse tree representation of goals with a trace goal.

compiler/mercury_to_mercury.m:
	Output the new kind of goal and its components.

compiler/hlds_goal.m:
	Extend the HLDS representation of scopes with a scope_reason
	representing trace goals.

	Add a mechanism (an extra argument in foreign_procs) to allow
	the representation of goals that evaluate runtime trace conditions.

	Since this requires modifying all code that traverses the HLDS,
	do some renames that were long overdue: rename not as negation,
	rename call as plain_call, and rename foreign_proc as
	call_foreign_proc. These renames all avoid using language keywords
	as function symbols.

	Change the way we record goals' purities. Instead of optional features
	to indicate impure or semipure, which is error-prone, use a plain
	field in the goal_info, accessed in the usual way.

	Add a way to represent that a goal contains a trace goal, and should
	therefore be treated as if it were impure when considering whether to
	optimize it away.

	Reformat some comments describing function symbols.

compiler/hlds_out.m:
	Output the new construct in the HLDS.

compiler/prog_io_util.m:
	Generalize the maybe[123] types to allow the representation of more
	than one error message. Add functions to extract the error messages.
	Add a maybe4 type. Rename the function symbols of these types to
	avoid massive ambiguity.

	Change the order of some predicates to bring related predicates
	next to each other.

compiler/prog_io.m:
compiler/prog_io_dcg.m:
compiler/prog_io_goal.m:
compiler/prog_io_pragma.m:
	Rework these modules almost completely to find and accumulate syntax
	errors as terms are being parsed. In some cases, this allowed us to
	replace "XXX this is a hack" markers with meaningful error-reporting
	code.

	In prog_io_goal.m, add code for parsing trace goals.

	In a bunch of places, update obsolete coding practices, such as using
	nested chains of closures instead of simple sequential code, and
	using A0 and A to refer to values of different types (terms and goals
	respectively). Use more meaningful variable names.

	Break up some too-large predicates.

compiler/superhomogeneous.m:
	Find and accumulate syntax errors as terms are being parsed.

compiler/add_clause.m:
	Add code to transform trace goals from the parse tree to the HLDS.
	This is where the IO state and mutable variable attributes of trace
	goals are handled.

	Eliminate the practice of using the naming scheme Body0 and Body
	to refer to values of different types (prog_item.goal and hlds_goal
	respectively).

	Use error_util for some error messages.

library/private_builtin.m:
	Add the predicates referred to by the transformation in add_clause.m.

compiler/goal_util.m:
	Rename a predicate to avoid ambiguity.

compiler/typecheck.m:
	Do not print error messages about missing clauses if some errors have
	been detected previously.

compiler/purity.m:
	Instead of just computing purity, compute (and record) also whether
	a goal contains a trace goal. However, treat trace goals as pure.

compiler/mode_info.m:
	Add trace goals as a reason for locking variables.

	Rename some function symbols to avoid ambiguity.

compiler/modes.m:
	When analyzing trace goal scopes, lock the scope's nonlocal variables
	to prevent them from being further instantiated.

compiler/det_analysis.m:
	Insist on the code in trace goal scopes being det or cc_multi.

compiler/det_report.m:
	Generate the error message if the code in a trace goal scope isn't det
	or cc_multi.

compiler/simplify.m:
	At the end of the front end, eliminate trace goal scopes if their
	compile-time condition is false. Transform trace goals with runtime
	conditions as described at the top.

	Treat goals that contain trace goals as if they were impure when
	considering whether to optimize them away.

compiler/mercury_compile.m:
	Tell simplify when it is being invoked at the end of the front end.

	Rename a predicate to avoid ambiguity.

compiler/trace_params.m:
	Provide the predicates simplify.m need to be able to evaluate the trace
	goal conditions regarding trace levels.

compiler/trace.m:
compiler/trace_gen.m:
	Rename the trace module as trace_gen, since "trace" is now an operator.

	Rename some predicates exported by the module, now that it is no longer
	possible to preface calls with "trace." as a module qualifier.

compiler/notes/compiler_design.html:
	Document this name change.

compiler/options.m:
	Rename the trace option as trace_level internally, since "trace"
	is now an operator. The user-visible name remains the same.

	Add the new --trace-flag option.

	Delete an obsolete option.

compiler/handle_options.m:
	Rename the function symbols of the grade_component type,
	since "trace" is now an operator.

compiler/llds.m:
	Extend the LLDS with a mechanism to refer to C global variables.
	For now, these are used to refer to C globals that will be created
	by mkinit to represent the initial values of the environment variables
	referred to by trace goals.

compiler/commit_gen.m:
	Check that no trace goal with a runtime condition survives to code
	generation; they should have been transformed by simplify.m.

compiler/code_gen.m:
	Tell commit_gen.m what kind of scope it is generating code for.

compiler/pragma_c_gen.m:
	Generate code for runtime conditions when handling the foreign_procs
	created by simplify.m.

compiler/code_info.m:
	Allow pragma_c_gen.m to record what environment variables it has
	generated references to.

compiler/proc_gen.m:
	Record the set of environment variables a procedure refers to
	in the LLDS procedure header, for efficient access by llds_out.m.

compiler/llds_out.m:
	Handle the new LLDS construct, and tell mkinit which environment
	variables need C globals created for them.

compiler/pd_util.m:
	Rename some predicates to avoid ambiguity.

compiler/*.m:
	Conform to the changes above, mainly the renames of function symbols
	and predicates, the changed signatures of some predicates, and the new
	handling of purity.

util/mkinit.c:
	Generate the definitions and the initializations of any C globals
	representing the initial status (set or not set) of environment
	variables needed by trace goals.

library/assoc_list.m:
	Add some predicates that are useful in prog_io*.m.

library/term_io.m:
	Minor cleanup.

tests/hard_coded/trace_goal_{1,2}.{m,exp}:
	New test cases to test the new construct, identical except for whether
	the trace goal is enabled at compile time.

tests/hard_coded/trace_goal_env_{1,2}.{m,exp}:
	New test cases to test the new construct, identical except for whether
	the trace goal is enabled at run time.

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

tests/invalid/*.err_exp:
	Update the expected output for the new versions of the error messages
	now being generated.
2006-07-27 05:03:54 +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
12deb40264 Rename all the get access predicates in these modules that don't
Estimated hours taken: 0.1
Branches: main

compiler/hlds_clauses.m:
compiler/hlds_pred.m:
	Rename all the get access predicates in these modules that don't
	already have put "get" in their name. (The names of the set access
	predicates were OK already.)

compiler/*.m:
	Conform to the above.

All this was done by this sed script:

s/clauses_info_varset/clauses_info_get_varset/
s/clauses_info_explicit_vartypes/clauses_info_get_explicit_vartypes/
s/clauses_info_vartypes/clauses_info_get_vartypes/
s/clauses_info_headvars/clauses_info_get_headvars/
s/clauses_info_clauses_rep/clauses_info_get_clauses_rep/
s/clauses_info_rtti_varmaps/clauses_info_get_rtti_varmaps/
s/pred_info_import_status/pred_info_get_import_status/
s/pred_info_arg_types/pred_info_get_arg_types/
s/pred_info_typevarset/pred_info_get_typevarset/
s/pred_info_tvar_kinds/pred_info_get_tvar_kinds/
s/pred_info_procedures/pred_info_get_procedures/
s/proc_info_context/proc_info_get_context/
s/proc_info_varset/proc_info_get_varset/
s/proc_info_vartypes/proc_info_get_vartypes/
s/proc_info_headvars/proc_info_get_headvars/
s/proc_info_inst_varset/proc_info_get_inst_varset/
s/proc_info_maybe_declared_argmodes/proc_info_get_maybe_declared_argmodes/
s/proc_info_argmodes/proc_info_get_argmodes/
s/proc_info_maybe_arglives/proc_info_get_maybe_arglives/
s/proc_info_declared_determinism/proc_info_get_declared_determinism/
s/proc_info_inferred_determinism/proc_info_get_inferred_determinism/
s/proc_info_goal/proc_info_get_goal/
s/proc_info_can_process/proc_info_get_can_process/
s/proc_info_rtti_varmaps/proc_info_get_rtti_varmaps/
s/proc_info_eval_method/proc_info_get_eval_method/
s/proc_info_is_address_taken/proc_info_get_is_address_taken/
s/proc_info_stack_slots/proc_info_get_stack_slots/
s/proc_info_liveness_info/proc_info_get_liveness_info/
s/proc_info_context/proc_info_get_context/
s/proc_info_context/proc_info_get_context/
s/proc_info_context/proc_info_get_context/
s/proc_info_context/proc_info_get_context/
s/proc_info_context/proc_info_get_context/
s/proc_info_context/proc_info_get_context/
s/proc_info_context/proc_info_get_context/
2006-03-27 09:36:34 +00:00
Zoltan Somogyi
3ebda6545f Move the stuff currently in hlds_pred.m that deals with clauses into a new
Estimated hours taken: 1.5
Branches: main

Move the stuff currently in hlds_pred.m that deals with clauses into a new
module, hlds_clauses.m.

Move the stuff currently in hlds_pred.m that deals with RTTI into a new
module, hlds_rtti.m.

Move the stuff currently in hlds_module.m that deals with predicate tables
into a new module, pred_table.m.

These changes make hlds_pred.m and hlds_module.m much more cohesive, but there
are no changes in algorithms.

compiler/hlds_clauses.m:
compiler/hlds_rtti.m:
compiler/pred_table.m:
	New modules as described above. In some cases, fix mixleading or
	ambiguous predicate names in the process, and convert a few predicates
	to functions.

compiler/hlds_pred.m:
compiler/hlds_module.m:
	Delete the stuff moved to other modules.

compiler/*.m:
	In modules that need the functionality moved a new module, import
	the new module. It is rare for all the new modules to be needed,
	and many modules don't need any of the new modules at all. (For
	example, of the 200+ modules that import hlds_module.m, only about 40
	need pred_table.m.)

	Conform to the few minor changes to e.g. predicate names.

compiler/notes/compiler_design.html:
	Document the new modules.
2006-03-24 03:04:20 +00:00
Zoltan Somogyi
be5b71861b Convert almost all the compiler modules to use . instead of __ as
Estimated hours taken: 6
Branches: main

compiler/*.m:
	Convert almost all the compiler modules to use . instead of __ as
	the module qualifier.

	In some cases, change the names of predicates and types to make them
	meaningful without the module qualifier. In particular, most of the
	types that used to be referred to with an "mlds__" prefix have been
	changed to have a "mlds_" prefix instead of changing the prefix to
	"mlds.".

	There are no algorithmic changes.
2006-03-17 01:40:46 +00:00
Zoltan Somogyi
5b8f96f61d Prepare for an extension of promise_equivalent_solutions that will allow us
Estimated hours taken: 5
Branches: main

Prepare for an extension of promise_equivalent_solutions that will allow us
to better handle values of user-defined types. The problem is that currently,
the deconstruction of a value of such a type can be followed only by code that
cannot fail, otherwise the cc_multi deconstruction is not in the required
single-solution context. If the following code is naturally semidet, this
can be worked around by turning it into det code returning a maybe and testing
the maybe outside the promise_equivalent_solutions, but this is inefficient,
and in any case it does not generalize to nondet code without even more
horrendous inefficiency and inconvenience. (You have to create a nondet closure
and call it outside the promise_equivalent_solutions.)

The solution I came up with is something is to have a construct that contains

	- a list of deconstructions on types with user-defined equality,
	- a goal, and
	- the list of outputs of that goal.

The idea is that this would be transformed into a conjunction of the first and
second items, and wrapped inside a special kind of conj that provides a scope
for the implicit promise, which is that the set of solutions of the goal in
the second item doesn't depend on what concrete terms the deconstructions
in the first item return out of the set of concrete terms they *could* return.
The deconstructions in the first item would be marked to tell determinism
analysis to effectively ignore the fact that they involve user-defined
equality.

The actual addition of that construct is left for a future change, after we
agree on the syntax.

compiler/hlds_goal.m:
	Generalize the existing promise_equivalent_solutions scope to a
	promise_solutions scope with a flag that says whether in the source
	code it was originally the existing "promise_equivalent_solutions"
	construct or the new construct (which doesn't exist yet, but is
	indicated by the symbol "same_solutions" for now).

	Replace the conj and par_conj hlds_goal_exprs with a single goal
	expression: conj with an additional argument which is either plain_conj
	or parallel_conj. This was part of an earlier design in which a third
	kind of disjunction took the role now assigned to the new kind of
	promise_solutions scope, but turned out to be a good idea anyway,
	since in many places the compiler does treat the two kinds of
	conjunctions the same. This part of the change is responsible for the
	fact that this change results in a net *reduction* of about 40 lines.

	Move the most frequently used kinds of goal expressions to the front
	of the type declaration to allow the compiler to make better decisions
	about tag allocation.

	Add the goal marker we will add to the deconstructions in the first
	item.

	Replace the true_goal and fail_goal predicates with functions to make
	them easier to use, and rename their variants that take a context
	argument to avoid unnecessary ambiguity.

compiler/*.m:
	Conform to the change in hlds_goal.m.

	Misc changes to make code more robust, e.g. replacing semidet
	predicates on goal expressions with functions returning bool.

	Misc cleanups, e.g. removal of unnecessary module qualifications
	that made lines too long, renaming predicates whose names include
	"disj" if they are also used to process parallel conjunctions (since in
	both parallel conjunctions and in disjunctions the goals are
	independent), and turning semidet predicates that switch on goal
	expressions into bool functions (to make similar changes more rebust
	in the future).
2006-02-24 05:49:43 +00:00
Zoltan Somogyi
5af71b60ac Remove support for the Aditi backend. It is a pain to have to update it every
Estimated hours taken: 2
Branches: main

Remove support for the Aditi backend. It is a pain to have to update it every
time a data structure changes when we don't see any benefit from it, and its
presence makes compilation of the compiler directory take about 10% longer
(since the Aditi backend modules are roughly 10% of the code in the compiler
directory). Deleting the Aditi-specific data structures from the HLDS should
also speed up compilation a little bit.

I have spoken to Rao and he is fine with this step.

Aditi users, if there are any, can continue to use the Aditi support in
release 0.12.*. I also tagged the last version on the trunk to support aditi
with the name "last_aditi". The need for modifications in this Aditi support
is likely to be very rare to nonexistent, if the recent past is any guide:
the Aditi backend hasn't seen a nontrivial modification in a year or more.

This diff removes a net 31492 lines.

compiler/add_aditi.m:
compiler/aditi_backend.pp:
compiler/aditi_builtin_ops.m:
compiler/context.m:
compiler/dnf.m:
compiler/magic.m:
compiler/magic_util.m:
compiler/rl.m:
compiler/rl_analyse.m:
compiler/rl_block.m:
compiler/rl_block_opt.m:
compiler/rl_code.m:
compiler/rl_dump.m:
compiler/rl_exprn.m:
compiler/rl_file.pp:
compiler/rl_gen.m:
compiler/rl_info.m:
compiler/rl_key.m:
compiler/rl_liveness.m:
compiler/rl_loop.m:
compiler/rl_opt.m:
compiler/rl_out.pp:
compiler/rl_relops.m:
compiler/rl_sort.m:
compiler/rl_stream.m:
	Remove these compiler modules, since they existed only to support the
	Aditi backend.

compiler/hlds_goal.m:
	Delete the Aditi-specific components of goals (e.g. the aditi-builtin
	kind of generic calls and Aditi-evaluated lambdas).

compiler/hlds_pred.m:
	Delete the Aditi-specific components of pred_infos.

compiler/prog_data.m:
	Delete the Aditi-specific items.

compiler/passes_aux.m:
	Don't worry about processing all procedures or just all non-Aditi
	procedures.

compiler/add_clause.m:
	Add a predicate from a deleted module that is now used only here.

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

compiler/notes/*.html:
	Remove references to the Aditi backend.

tests/invalid/aditi.m:
tests/invalid/aditi_errors.err_exp:
tests/invalid/aditi_errors.m:
tests/invalid/aditi_private_builtin.m:
tests/invalid/aditi_state_errors.err_exp:
tests/invalid/aditi_state_errors.m:
tests/invalid/aditi_update_derived_relation.err_exp:
tests/invalid/aditi_update_derived_relation.m:
tests/invalid/aditi_update_errors.err_exp:
tests/invalid/aditi_update_errors.m:
tests/invalid/aditi_update_mode_errors.err_exp:
tests/invalid/aditi_update_mode_errors.m:
tests/valid/aditi.m:
tests/valid/aditi_calls_mercury.m:
tests/valid/aditi_error_bug.m:
tests/valid/aditi_error_bug2.m:
tests/valid/aditi_error_bug3.m:
tests/valid/aditi_private_builtin.m:
tests/valid/aditi_query.m:
tests/valid/aditi_update.m:
tests/valid/base_relation.m:
tests/valid/base_relation2.m:
tests/valid/ite_to_disj.m:
	Remove these Aditi-specific tests.

tests/*/Mmakefile:
	Remove the references to these Aditi-specific tests.
2006-02-23 09:37:30 +00:00
Julien Fischer
45fdb6c451 Use expect/3 in place of require/2 throughout most of the
Estimated hours taken: 4
Branches: main

compiler/*.m:
	Use expect/3 in place of require/2 throughout most of the
	compiler.

	Use unexpected/2 (or sorry/2) in place of error/1 in more
	places.

	Fix more dodgy assertion error messages.

	s/map(prog_var, mer_type)/vartypes/ where the latter is meant.
2005-11-28 04:11:59 +00:00
Julien Fischer
5f589e98fb Various cleanups for the modules in the compiler directory.
Estimated hours taken: 4
Branches: main

Various cleanups for the modules in the compiler directory.  The are
no changes to algorithms except the replacement of some if-then-elses
that would naturally be switches with switches and the replacement of
most of the calls to error/1.

compiler/*.m:
	Convert calls to error/1 to calls to unexpected/2 or sorry/2 as
	appropriate throughout most or the compiler.

	Fix inaccurate assertion failure messages, e.g. identifying the
	assertion failure as taking place in the wrong module.

	Add :- end_module declarations.

	Fix formatting problems and bring the positioning of comments
	into line with our current coding standards.

	Fix some overlong lines.

	Convert some more modules to 4-space indentation.  Fix some spots
	where previous conversions to 4-space indentation have stuffed
	the formatting of the code up.

	Fix a bunch of typos in comments.

	Use state variables in more places; use library predicates
	from the sv* modules where appropriate.

	Delete unnecessary and duplicate module imports.

	Misc. other small cleanups.
2005-11-17 15:57:34 +00:00
Zoltan Somogyi
f9fe8dcf61 Improve the error messages generated for determinism errors involving committed
Estimated hours taken: 8
Branches: main

Improve the error messages generated for determinism errors involving committed
choice contexts. Previously, we printed a message to the effect that e.g.
a cc pred is called in context that requires all solutions, but we didn't say
*why* the context requires all solutions. We now keep track of all the goals
to the right that could fail, since it is these goals that may reject the first
solution of a committed choice goal.

The motivation for this diff was the fact that I found that locating the
failing goal can be very difficult if the conjunction to the right is
a couple of hundred lines long. This would have been a nontrivial problem,
since (a) unifications involving values of user-defined types are committed
choice goals, and (b) we can expect uses of user-defined types to increase.

compiler/det_analysis.m:
	Keep track of goals to the right of the current goal that could fail,
	and include them in the error representation if required.

compiler/det_report.m:
	Include the list of failing goals to the right in the representations
	of determinism errors involving committed committed choice goals.

	Convert the last part of this module that wasn't using error_util
	to use error_util. Make most parts of this module just construct
	error message specifications; print those specifications (using
	error_util) in only a few places.

compiler/hlds_out.m:
	Add a function for use by the new code in det_report.m.

compiler/error_util.m:
	Add a function for use by the new code in det_report.m.

compiler/error_util.m:
compiler/compiler_util.m:
	Error_util is still changing reasonably often, and yet it is
	included in lots of modules, most of which need only a few simple
	non-parse-tree-related predicates from it (e.g. unexpected).
	Move those predicates to a new module, compiler_util.m. This also
	eliminates some undesirable dependencies from libs to parse_tree.

compiler/libs.m:
	Include compiler_util.m.

compiler/notes/compiler_design.html:
	Document compiler_util.m, and fix the documentation of some other
	modules.

compiler/*.m:
	Import compiler_util instead of or in addition to error_util.
	To make this easier, consistently use . instead of __ for module
	qualifying module names.

tests/invalid/det_errors_cc.{m,err_exp}:
	Add this new test case to test the error messages for cc contexts.

tests/invalid/det_errors_deet.{m,err_exp}:
	Add this new test case to test the error messages for unifications
	inside function symbols.

tests/invalid/Mmakefile:
	Add the new test cases.

tests/invalid/det_errors.err_exp:
tests/invalid/magicbox.err_exp:
	Change the expected output to conform to the change in det_report.m,
	which is now more consistent.
2005-10-28 02:11:03 +00:00
Zoltan Somogyi
b2012c0c0e Rename the types 'type', 'inst' and 'mode' to 'mer_type', 'mer_inst'
Estimated hours taken: 8
Branches: main

compiler/*.m:
	Rename the types 'type', 'inst' and 'mode' to 'mer_type', 'mer_inst'
	and 'mer_mode'. This is to avoid the need to parenthesize these type
	names in some contexts, and to prepare for the possibility of a parser
	that considers those words to be reserved words.

	Rename some other uses of those names (e.g. as item types in
	recompilation.m).

	Delete some redundant synonyms (prog_type, mercury_type) for mer_type.

	Change some type names (e.g. mlds__type) and predicate names (e.g.
	deforest__goal) to make them unique even without module qualification.

	Rename the function symbols (e.g. pure, &) that need to be renamed
	to avoid the need to parenthesize them. Make their replacement names
	more expressive.

	Convert some more modules to four space indentation.

	Avoid excessively long lines, such as those resulting from the
	automatic substitution of 'mer_type' for 'type'.
2005-10-24 04:14:34 +00:00
Zoltan Somogyi
b54ab42d70 A simple tool for performing substitutions on the source files of the
Estimated hours taken: 0.5
Branches: main

tools/subst:
	A simple tool for performing substitutions on the source files of the
	compiler.

compiler/*.m:
	Change the names of the get predicates operating on module_infos to
	include "get" in the name, for uniformity. This was done mostly by
	the following sed script, with some manual cleanup afterwards to reduce
	excessive line lengths.

s/module_info_types/module_info_get_type_table/
s/module_info_set_types/module_info_set_type_table/
s/module_info_insts/module_info_get_inst_table/
s/module_info_set_insts/module_info_set_inst_table/
s/module_info_modes/module_info_get_mode_table/
s/module_info_set_modes/module_info_set_mode_table/
s/module_info_ctors/module_info_get_cons_table/
s/module_info_set_ctors/module_info_set_cons_table/
s/module_info_classes/module_info_get_class_table/
s/module_info_set_classes/module_info_set_class_table/
s/module_info_instances/module_info_get_instance_table/
s/module_info_set_instances/module_info_set_instance_table/
s/module_info_superclasses/module_info_get_superclass_table/
s/module_info_set_superclasses/module_info_set_superclass_table/
s/module_info_assertion_table/module_info_get_assertion_table/
s/module_info_exclusive_table/module_info_get_exclusive_table/
s/module_info_ctor_field_table/module_info_get_ctor_field_table/
s/module_info_name/module_info_get_name/
s/module_info_globals/module_info_get_globals/
s/module_info_contains_foreign_types/module_info_get_contains_foreign_types/
s/module_info_num_errors/module_info_get_num_errors/
s/module_info_type_ctor_gen_infos/module_info_get_type_ctor_gen_infos/
s/module_info_stratified_preds/module_info_get_stratified_preds/
s/module_info_unused_arg_info/module_info_get_unused_arg_info/
s/module_info_exception_info/module_info_get_exception_info/
s/module_info_type_spec_info/module_info_get_type_spec_info/
s/module_info_no_tag_types/module_info_get_no_tag_types/
s/module_info_analysis_info/module_info_get_analysis_info/
s/module_info_aditi_top_down_procs/module_info_get_aditi_top_down_procs/
2005-09-30 08:08:49 +00:00
Zoltan Somogyi
67165d0262 Fix overlong lines.
Estimated hours taken: 3
Branches: main

compiler/base_typeclass_info.m:
	Fix overlong lines.

compiler/goal_util.m:
	Minor style fix.

compiler/lambda.m:
	Convert to four-space indentation. Other style fixes.

compiler/deconstruct.m:
compiler/io.m:
compiler/string.m:
compiler/term.m:
compiler/term_io.m:
compiler/type_desc.m:
	Convert to four-space indentation. Other style fixes.

library/construct.m:
	Minor style fix.
2005-09-19 04:29:01 +00:00
Zoltan Somogyi
df0d9036cf Optimize calls that would be tail calls in Prolog but are followed by
Estimated hours taken: 40
Branches: main

Optimize calls that would be tail calls in Prolog but are followed by
construction unifications in Mercury: last call modulo construction.
For now, the optimization is available only for the LLDS backend.

compiler/lco.m:
	Turn this module from a placeholder to a real implementation
	of the optimization.

compiler/hlds_goal.m:
	Allow lco.m to attach to construction unifications a note that says
	that certain arguments, instead of being filled in by the unification,
	should have their addresses taken and stored in the corresponding
	variables.

	Group this note together with the note that asks for term size
	profiling to avoid an increase in the sizes of goals in the compiler
	in most cases.

compiler/hlds_pred.m:
	Provide a predicate for setting the name of a predicate after its
	creation. This functionality is used by lco.m.

	Extend the pred_transformation part of the pred_origin type to allow
	it to express that a procedure was created by lco.m.

	List the new primitive store_at_ref as a no-typeinfo builtin.

	Fix some problems with indentation.

compiler/layout_out.m:
	Handle the new pred_transformation.

compiler/unify_gen.m:
	When processing construction unifications that have the new feaure
	turned on, perform the requested action.

	Fix some departures from coding style. Shorten lines by deleting
	unnecessary module qualifications. Add some auxiliary predicates
	to make the code easier to read.

compiler/var_locn.m:
	Fix an earlier oversight: when materializing variables inside rvals
	and lvals, look inside memory references too. Previously, the omission
	didn't matter, since we didn't generate such references, but now we do.

	Fix some departures from coding style.

compiler/llds_out.m:
	Fix some old XXXs in code handling memory references. We didn't use to
	generate such references, but now we do.

	Move some functionality here from code_aux.m.

compiler/code_info.m:
	Provide some primitive operations needed by the new code in var_locn.m.

	Delete an unneeded predicate.

compiler/options.m:
	Rename the existing option optimize_constructor_last_call as
	optimize_constructor_last_call_accumulator, since that optimization
	is done by accumulator.m.

	Make optimize_constructor_last_call be the option that calls for the
	new optimization.

compiler/handle_options.m:
	Handle the implications of the new option.

compiler/mercury_compile.m:
	Invoke the lco module by its new interface.

librrary/private_builtin.m:
	Add a new primitive operation, store_at_ref, for use by the new
	optimization.

	Switch the module to four-space indentation.

compiler/add_clause.m:
	Comment out the warning for clauses for builtin, since this is needed
	to bootstrap the addition of the new builtin.

compiler/term_constr_initial.m:
	Handle the new builtin.

compiler/accumulator.m:
	Conform to the change in options.

compiler/builtin_ops.m:
	Provide a third template for builtins, for use by store_at_ref.

	Convert the file to four-space indentation.

compiler/call_gen.m:
	Generate code following the new builtin template.

compiler/rl_exprn.m:
	Minor changes to conform to the changes in builtin templates.

compiler/quantification.m:
	Minor changes to conform to the changes in construct unifications.

	Don't make the "get" predicates operating on quantification_infos
	to return the "new" quantification_info: it is always the same
	as the old one.

compiler/aditi_builtin_ops.m:
compiler/common.m:
compiler/deep_profiling.m:
compiler/higher_order.m:
compiler/hlds_out.m:
compiler/lambda.m:
compiler/magic_util.m:
compiler/ml_unify_gen.m:
compiler/modecheck_unify.m:
compiler/polymorphism.m:
compiler/size_prof.m:
	Minor changes to conform to the changes in construct unifications.

compiler/dependency_graph.m:
	Add a new predicate to recompute the dependency information,
	even if a previous (and possibly now inaccurate) version is present.

	Change the interface to make it clearer, by changing bools into types
	specific to the situation.

	Convert the file to four-space indentation.

compiler/mode_constraints.m:
	Minor changes to conform to the changes in dependency_graph.m.

compiler/code_aux.m:
	Delete this module. Half its functionality has been moved into
	llds_out.m, half to middle_rec.m (its only user).

compiler/goal_form.m:
	Move the predicates in this module that are used only by middle_rec.m
	to middle_rec.m.

	Convert the file to four-space indentation.

compiler/goal_util.m:
compiler/det_util.m:
	Move update_instmap from det_util to goal_util, since it is usefulness
	extends beyond determinism analysis.

	Convert det_util.m to four-space indentation.

compiler/middle_rec.m:
	Move here the code required only here from code_aux and goal_form.
	Update the moved code for the changes in construct unifications.
	The updates are specific to middle_rec.m: they wouldn't be of use
	to other modules. They basically say that any code that takes the
	addresses of fields cannot be handled by middle_rec.m.

compiler/code_gen.m:
compiler/det_analysis.m:
compiler/live_vars.m:
compiler/ll_backend.m:
compiler/loop_inv.m:
compiler/switch_detection.m:
compiler/switch_gen.m:
compiler/notes/compiler_design.html:
	Minor changes to conform to the deletion of code_aux.m and/or the
	movement of code from det_util to goal_util.m.

compiler/opt_debug.m:
	Print info for vars in rvals.

compiler/hlds_module.m:
	Convert a lambda to an explicit predicate to make some code easier to
	read.

	Switch the module to four-space indentation.
2005-09-13 04:56:20 +00:00
Zoltan Somogyi
2f06c5b8fe Don't just detect when successive unifications unify the same variable with
Estimated hours taken: 6
Branches: main

Don't just detect when successive unifications unify the same variable with
incompatible function symbols: also issue a warning.

compiler/ml_code_gen.m:
compiler/stratify.m:
compiler/table_gen.m:
mdbcomp/trace_counts.m:
	Fix pieces of code that get the new warning.

compiler/modecheck_unify.m:
	When detecting such unifications, add warnings for them, except if
	the initial inst of the current restricts the set of allowed bindings
	of the input arguments. If the initial inst of X is bound(f), then
	an otherwise correct unification Y = g may fail if Y has been computed
	from X. (We don't whether it has, so we have to be conservative.)
	There are examples of such code in the library, e.g. functor in
	deconstruct.m.

	Factor out some common code.

compiler/mode_errors.m:
	Add the infrastructure needed for printing warnings, and the two forms
	of this warning in particular.

compiler/mode_info.m:
	Extend the mode_info structure to make room for warnings, and for the
	initial inst of the procedure arguments.

	Switch to four-space indentation.

compiler/inst_util.m:
	Add a predicate that tests whether an inst may restrict the set of
	possible cons_ids a variable may be bound to.

	Change the argument order of some predicates to allow them to be
	used in higher order code. We don't need to make the switched-on
	argument the first argument anymore.

	Switch to four-space indentation.

compiler/hlds_goal.m:
	Change the argument order of some predicates to allow the use of state
	variables.

compiler/higher_order.m:
compiler/instmap.m:
compiler/mode_constraints.m:
compiler/mode_debug.m:
compiler/mode_ordering.m:
compiler/modecheck_call.m:
compiler/trace.m:
	Conform to the changed argument orders described above.

	Switch to four-space indentation.

compiler/common.m:
compiler/inst_match.m:
compiler/hlds_pred.m:
compiler/lambda.m:
compiler/magic.m:
compiler/magic_util.m:
compiler/modes.m:
compiler/pd_util.m:
compiler/post_typecheck.m:
compiler/unique_modes.m:
	Conform to the changed argument orders described above.

tests/invalid/occurs.err_exp:
	Expect the extra warning.

tests/warnings/Mmakefile:
	Enable the unify_f_g test case I accidentally committed earlier.

tests/warnings/unify_f_g.{m,err_exp}:
	Finalize that test case.

tests/warnings/simple_code.err_exp:
	Expect the extra warning.
2005-08-27 09:42:10 +00:00
Mark Brown
37ba982839 Another step towards the removal of constraints and types from the arguments
Estimated hours taken: 25
Branches: main

Another step towards the removal of constraints and types from the arguments
of typeclass_info/1 and type_info/1.  This involves ensuring that the
rtti_varmaps structure contains enough information for any code that
previously needed to refer to these arguments.

compiler/common.m:
	When generating assignments between variables that hold type infos
	or typeclass infos, calculate a type substitution representing the
	aliasing of any type variables that results.  This aliasing can
	occur if the same existentially typed data structure is deconstructed
	twice.  The resulting substitution is applied to the simplify_info.

	Update the rtti_varmaps if there is information stored for one of
	the variables in the assignment, but not the other.

compiler/simplify.m:
	Provide a means to apply a type substitution to the fields in
	a simplify_info that may contain types.

compiler/hlds_pred.m:
	Don't use an injection to model the typeclass_info_varmap.  The
	previous forward mapping was never intended to be complete: it
	only covered constraints that could be reused by later goals when
	doing the polymorphism transformation.  Some prog_vars which hold
	typeclass_infos cannot be reused since they may no longer be in
	scope, for example, prog_vars for typeclass_infos that were
	constructed in an earlier disjunct.

	Instead of an injection we just use two separate maps.  The reverse
	map (from prog_vars to constraints) includes all known constraints.
	The forward map (from constraints to prog_vars) only covers
	constraints for which it is safe to reuse the prog_var.  These
	two maps are kept consistent be the fact that the latter map is
	never updated directly; it only has entries added when a particular
	prog_var is flagged as reusable.

	Document the fact that when looking up a typeclass_info var, we only
	consider those prog_vars which have been flagged as reusable.

	Export a predicate to update already existing type_info_type
	information.  This is used when introducing exists_cast goals.

	Export a predicate to duplicate the rtti_var_info from one variable
	to another.  This is used when introducing new variables in
	saved_vars.m, and when updating the rtti_varmaps in common.m.

	Export a predicate to return all known type_info and typeclass_info
	vars.  This is used by hlds_out to print out the table.

	When applying substitutions to the rtti_varmaps, add a sanity check
	to ensure that the various maps remain consistent.

	Don't provide an interface to transform constraints.  Instead,
	provide an interface to transform types (which is also applied to
	the constraint arguments).  This interface is required when
	fully expanding equivalence types, in which case all types need
	to be expanded, not just those appearing in constraints.

compiler/clause_to_proc.m:
	When adding exists_cast goals, ensure that the rtti_varmaps structure
	is updated with the new information.  This addresses an XXX comment
	that was left here from an earlier change.

compiler/equiv_type_hlds.m:
	Fully expand equivalence types in all types in the rtti_varmaps,
	not just those types appearing in constraints.

compiler/goal_util.m:
compiler/lambda.m:
	When calculating extra nonlocal typeinfos or constraints on lambda
	expressions, only consider those constraints that are able to be
	reused.  These are the only constraints that the goal in question
	could possibly have used.

compiler/hlds_out.m:
	When printing out the typeclass_info_varmap, only consider the
	reusable constraints.  These are the only ones that have entries
	in the typeclass_info_varmap.

	Print out the available variable info for any type_info or
	typeclass_info variables.

compiler/polymorphism.m:
	Thread the entire poly_info through
	polymorphism__new_typeclass_info_var, since it now makes use of
	three fields within this structure.  Ensure that the rtti_varmaps
	field is updated with the information about the new typeclass_info
	var.

	Flag all universal constraints from the head and existential
	constraints from the body as being reusable.  The program variables
	for these typeclass_infos will always be in scope wherever the
	constraint could appear.  Typeclass infos that have been constructed
	from proofs within the current procedure may not be still in scope,
	so they are not flagged as reusable.

compiler/saved_vars.m:
	Make sure the rtti_varmaps is updated if we rename a variable that
	contains a type_info or typeclass_info.
2005-08-16 15:36:19 +00:00
Mark Brown
38d9ef3479 Package the type_info_varmap and typeclass_info_varmap types into an ADT
Estimated hours taken: 25
Branches: main

Package the type_info_varmap and typeclass_info_varmap types into an ADT
called rtti_varmaps.  There are two main purposes for this:

	- We wish to extend this set of maps with new maps.  Doing this
	will be a lot easier and less error prone if all of the maps are
	packaged in a single data structure.

	- Any new maps that we add may contain redundant information that
	just makes searching the maps more efficient.  Therefore they must
	be kept consistent with the existing maps.  Having all the maps
	inside an ADT makes it easier to ensure this.

This change also includes two extensions to the maps.  First, the
typeclass_info_map is made reversible so that it is possible to efficiently
look up the constraint for a given typeclass_info variable.  Second, a new
map from prog_vars to types makes it possible to efficiently look up the
type that a given type_info variable is for.  These two changes mean that
it is no longer necessary to consult the argument of type_info/1 or
typeclass_info/1 to find this information.  (We still do put that information
there, though; changing the RTTI is left for a separate change.)

compiler/hlds_pred.m:
	Move items relating to type_infos and typeclass_infos into a section
	of their own.

	Add a type `rtti_var_info' to hold information about the contents
	of a type_info or typeclass_info variable.

	Define the rtti_varmaps abstract data type.  This data structure
	consists of the type_info_varmap and the typeclass_info_varmap.
	Add a new map, type_info_type_map, which is like the inverse
	to the type_info_varmap.  The difference is that the latter can
	point to locations that are inside a typeclass_info variable,
	whereas the former only refers to type_info variables.  Note that
	the combined maps do not form a bijection, or even an injection,
	since it is possible for two different type variables to point to
	the same location (that is, if they are aliased).

	Make the typeclass_info_varmap reversible, by using the new module
	injection.m.  Unlike the type_info_varmap, this map is always
	injective since the same typeclass_info cannot be used for two
	different constraints.

	The predicates rtti_det_insert_type_info_locn and set_type_info_locn,
	which update the type_info_varmap, contain sanity checks to ensure
	that only type variables that have already been registered with
	the type_info_type_map are used, and that the information in both
	maps is consistent.

	Use the rtti_varmaps structure in proc_info and clauses_info, in
	place of type_info_varmap and typeclass_info_varmap.

compiler/polymorphism.m:
	Remove polymorphism__type_info_or_ctor_type/2 and
	polymorphism__typeclass_info_class_constraint/2, to ensure that
	nobody tries to use the information in the type argument.  Replace
	them with two similar predicates that test if a type is type_info
	or typeclass_info, but that don't return the argument.

	Ensure that the new type_info_type_map in the rtti_varmaps is kept
	up to date by threading the rtti_varmaps through a few more places.
	Some of these places are exported, so this part of the change
	affects other modules as well.

	Fix a comment that referred to a non-existent predicate.

compiler/type_util.m:
	Remove the predicates apply_substitutions_to_var_map/5 and
	apply_substitutions_to_typeclass_var_map/5.  The functionality
	is now provided by the new ADT.

compiler/cse_detection.m:
	Rewrite update_existential_data_structures/4 to use the interface
	provided by rtti_varmaps.  The algorithm for doing this has changed
	in the following ways:

		- The first pass, which builds a map from changed locations
		in the first branch to the tvars concerned, is modified
		slightly to traverse over the keys instead of over key-value
		pairs.

		- The second pass, which previously calculated the induced
		type substitution and reconstructed the type_info_varmap
		now only does the former.

		- Applying the prog_var transformation and the induced type
		substitution is done at the end, using the interface to
		rtti_varmaps.

compiler/goal_util.m:
	Rewrite goal_util__extra_nonlocal_typeinfos/6 to avoid the need
	for using map__member/3 on the typeclass_info_varmap (about which
	the existing comments say "this is probably not very efficient..."),
	and to be more efficient in general.

	Previously, we nondeterministically generated non-local type vars
	and then tested each constraint to see if it had the type var in it.
	Now, we go through each constraint one at a time and check if any of
	the type variables in it are non-local.  This is more efficient
	because we only need to find one non-local type in order to include
	the typeclass_info in the non-locals -- the remaining (duplicate)
	solutions are pruned away.

compiler/higher_order.m:
	Use the new maps instead of looking at the arguments of type_info/1
	and typeclass_info/1 types.  We plan to remove this information
	from type_info and typeclass_info types in future.

	Previously, this module used the type argument in order to update
	the varmaps when the curried arguments of a higher order call are
	added as arguments to the procedure in which the call occurs.
	We now look up this information at the point where the curried arg
	variables are known, and store this information in higher_order_arg
	alongside the types where it used to be stored.  This structure is
	threaded through to the place where the information is needed.

	Fix a cut and paste bug in higher_order_arg_depth/1.  It was
	previously calling higher_order_args_size/1 in the recursive
	call, instead of calling higher_order_args_depth/1.

compiler/inlining.m:
	In inlining__do_inline_call, apply the substitutions to the entire
	rtti_varmaps structure, not just to the type_info_varmap.  (XXX Is
	there a good reason why the substitution should _not_ be applied
	to the typeclass_info varmap?)

compiler/magic_util.m:
	Avoid using polymorphism__type_info_or_ctor_type/2 and
	polymorphism__typeclass_info_class_constraint/2, as these are
	no longer supported.

compiler/*.m:
	Straightforward changes to use the new ADT.

library/injection.m:
	New library module.  This provides an `injection' type which is
	similar to the existing `bimap' type in that it implements
	back-to-back maps, but doesn't have such stringent invariants
	imposed.  In particular, the reverse map is not required to be
	injective.

	This type is used to model the relationship between prog_constraints
	and program variables that hold typeclass_infos for them.  Namely,
	the typeclass_info for a constraint can be held in two different
	variables, but one variable can never hold the typeclass_info for
	two distinct constraints.

library/library.m:
	Add the new library module.

library/list.m:
	Add list__foldl_corresponding and list__foldl2_corresponding, which
	traverse two lists in parallel, which one or two accumulators, and
	abort if there is a length mismatch.

NEWS:
	Mention the changes to the standard library.
2005-07-22 12:32:07 +00:00
Ian MacLarty
f362356b17 Make the user friendly names of predicates introduced by lambda expressions
Estimated hours taken: 4
Branches: main

Make the user friendly names of predicates introduced by lambda expressions
(more) unique.  This is necessary so they can be distinguished from each other
in trace count files.

If two or more lambda expression appear in the same context, then include
their sequence number in that context in the user friendly predicate name.

compiler/hlds_module.m:
	Instead of keeping a counter of how many lambdas appear in a module,
	keep a seperate counter for each context (filename/lineno).  This
	way we only need to include the sequence number in the predicate
	name if there are two or more lambdas in the same context.

compiler/hlds_pred.m:
	Add a new field to the `lambda' functor which records the count of the
	lambda expressin in its context.

compiler/hlds_out.m:
	Unify with lambda/3 instead of lambda/2.

compiler/lambda.m:
	Use the sequence number of the lambda expression in its context
	when creating the predicate origin.

compiler/layout.m:
	Store the origin of a closure predicate in the layout data of the
	closure, so that it's user friendly name can be included in the
	generated C code.

compiler/layout_out.m:
	When generating a user friendly name for lambda expression predicates,
	include the sequence number of the lambda expression if the sequence
	number is greater than one.

compiler/stack_layout.m:
	Pass the closure origin to the closure layout construction predicate.

compiler/unify_gen.m:
	Pass the closure origin when constructing the closure layout.

tests/debugger/Mmakefile:
tests/debugger/lambdatest.exp:
tests/debugger/lambdatest.inp:
tests/debugger/lambdatest.m:
	Test that the predicate names for lambda expressions are unique,
	even if they appear in the same call.

tests/debugger/higher_order.exp:
tests/debugger/lambda_expr.exp:
tests/debugger/declarative/find_origin.exp:
tests/debugger/declarative/find_origin.exp2:
tests/debugger/declarative/higher_order.exp:
tests/debugger/declarative/higher_order.exp2:
tests/debugger/declarative/ho2.exp2:
tests/debugger/declarative/trust.exp:
tests/hard_coded/deconstruct_arg.exp:
	Expect the new (more) unique predicate names.
2005-05-26 00:17:06 +00:00
Mark Brown
4427723508 Remove the assumption made by polymorphism.m that all type variables
Estimated hours taken: 240
Branches: main

Remove the assumption made by polymorphism.m that all type variables
appearing in class constraints also appear in the type being constrained.
This is a first step towards adding functional dependencies, since in the
presence of functional dependencies (or "improvement" in general) this
assumption no longer holds.

The assumption made by polymorphism manifests itself in the fact that
constraints on atomic goals are reconstructed by unifying the types of
formal parameters with the types of actual arguments, and then applying
the resulting substitution to the constraints.  Any type variables in
constraints that don't appear in the formal parameters will therefore
remain unbound.

This change overcomes the assumption by building up a map from constraint
identifiers to constraints during typechecking, and then looking up this
map in order to reconstruct the constraint during the polymorphism
transformation.

To support this, the type 'class_constraint' has been removed and replaced
by two distinct types, 'prog_constraint' and 'hlds_constraint'.  The former
is part of the parse tree and holds the same information as the old
class_constraint.  The latter is part of the HLDS, and is used during
typechecking; in addition to the information in prog_constraints, it also
stores a set of identifiers that represent where the constraint came from.
These identifiers are used as the keys in the aforementioned map.

At this stage the constraint identifiers are only used by typechecking to
build the constraint map.  Other passes use either prog_constraints or
hlds_constraints with an empty set of identifiers.

compiler/hlds_data.m:
	Define the constraint_id type, which is used to uniquely identify
	class constraints.  A better scheme than this one has been suggested,
	but that will be left to a later change.  An XXX comment to that
	effect has been added.

	Define the hlds_constraint type, which is like prog_constraint but
	it also includes a set of constraint_ids.  Define a set of predicates
	to initialise and manipulate these.

	Define the constraint_map type here.  Move the definition of
	constraint_proof_map to here, where it more sensibly belongs.

	Update the comments in hlds_instance_defn slightly, with information
	that I found I needed to know when making this change.

compiler/hlds_pred.m:
	Add a field to the pred_info to store the constraint_map.

	Move the definition of constraint_proof_map from here.

compiler/hlds_out.m:
	Print out a representation of the constraint map if it isn't empty.

compiler/type_util.m:
	Change the predicates that used to operate on class_constraints so
	that they now operate on hlds_constraints.  The old versions of these
	predicates have now moved to prog_util.

	Add some utility predicates to manipulate constraint_maps.

	Add a predicate to apply a variable renaming to constraint_proof_maps.

compiler/prog_data.m:
	Rename class_constraint(s) to prog_constraint(s).

compiler/prog_util.m:
	Provide a set of predicates for manipulating prog_constraints.

compiler/typecheck.m:
	Ensure that goal_paths are filled in before the first iteration
	of typechecking.

	Pass the hlds_goal_info down through typecheck_goal_2 so that the
	goal_path can be retrieved when needed to assign identifiers to
	constraints.  Thread the goal_path through to wherever it is needed.

	Store hlds_constraints in the args_type_assign rather than
	prog_constraints, so that the required information is available
	when creating the new set of type_assigns.  Do likewise for the
	cons_type_info type.  Don't pass the module_info through
	make_pred_cons_info*, since it isn't used.  Do pass the goal_path,
	though, so that constraints in cons_type_infos can be given the
	correct identifier.

	Add a constraint_map field to the typecheck_info, initialised to empty.

	When retrieving the final information from a typecheck_info, return
	the resulting constraint_map, after applying any type bindings.
	Ensure that any constraints that may not have been entered into the
	constraint_map are put there now.  Call the new predicate in type_util
	to rename the constraint_proof_map, rather than doing it longhand
	here.

	Make the following changes to context reduction:

		- Thread the constraint_map through, so that it can be updated
		as constraints are eliminated.

		- Instead of simply calling sort_and_remove_dups on the
		set of constraints remaining after one iteration, merge the
		constraints in such a way that the complete set of
		constraint_ids is retained.

		- Disregard the constraint_ids when deleting newly introduced
		constraints that are equivalent to constraints that have
		already been seen.

		- Simplify the code of find_matching_instance_rule_2 by
		moving the deterministic code out of the condition of the
		if-then-else.

	Move find_first_map into the library.

compiler/polymorphism.m:
	Ensure that the goal_path is set when constructing lambda goals.

	In process_call, look up the constraints in the constraint_map
	using the goal_path as part of the key, rather than calculating
	the constraints by applying the ParentToActual type substitution.
	Rearrange this code so that it is divided into easier to understand
	blocks.

	Add a field to the poly_info to store the constraint_map, and
	initialise it from the pred_info.

compiler/goal_path.m:
	Fill slots in lambda_goals, since constraints inside these will
	otherwise not be identified properly.  The goal_paths inside here
	do not entirely make sense, since there is no goal_path_step for
	the lambda_goal itself.  However, there is enough information
	retained to distinguish these goal_paths from any other possible
	goal_path, which is all that we require to identify constraints.

	Add a warning not to fill in the goal slots between the typechecking
	and polymorphism passes, since doing so could potentially render the
	constraint_maps incorrect.

compiler/make_hlds.m:
	Initialise the constraint_map to empty in pred_infos.

	Move the code for updating the superclass_table into a separate
	predicate.  Initially this change was made because, in an earlier
	version of the change, the superclass_table had some extra
	information that needed to be filled in.  That part of the change
	is not needed in this diff, but the new predicate simplifies the
	code a bit so I've left it there.

compiler/check_typeclass.m:
	Convert the prog_constraints into hlds_constraints before passing
	them to typecheck.reduce_context_by_rule_application.  They are
	assigned no identifiers, since these constraints are not required
	to be put into the constraint map.

	Change the name of the function get_constraint_id to
	get_constraint_class_id, since it would now be ambiguous otherwise.

compiler/cse_detection.m:
	Import parse_tree__prog_util, since that is where renamings of
	prog_constraints are now defined.

compiler/higher_order.m:
	Initialise pred_infos here with an empty constraint_map.

compiler/post_typecheck.m:
	When binding type vars to void, apply the void substitution to the
	constraint_map.

compiler/table_gen.m:
	Pass the constraint_map when creating a new pred_info.

compiler/unused_args.m:
	Create the pred_info with an empty constraint_map.  The constraint_map
	won't be used by this stage anyway.

compiler/*.m:
	Update to use the new type names.  Also update to use the existing
	type synonyms typeclass_info_varmap and constraint_proof_map.

	Change names of predicates and functions to use prog_constraint
	instead of class_constraint, where applicable.

library/list.m:
	Add find_first_map from typecheck.  Also add find_first_map{2,3},
	since at one stage during development I needed find_first_map3, and,
	although it's not used in the current diff, there is little point
	removing it now.
2005-04-01 14:29:19 +00:00
Zoltan Somogyi
8b8b3b7d3f Replace the some() HLDS goal with a more general scope() goal, which can be
Estimated hours taken: 12
Branches: main

Replace the some() HLDS goal with a more general scope() goal, which can be
used not just for existential quantification but also for other purposes.

The main such purposes are new goal types that allow the programmer
to annotate arbitrary goals, and not just whole procedure bodies, with the
equivalents of promise_pure/promise_semipure and promise_only_solution:

	promise_pure ( <impure/semipure goal> )
	promise_semipure ( <impure goal> )

	promise_equivalent_solutions [OutVar1, OutVar2] (
		<cc_multi/cc_nondet goal that computed OutVar1 & OutVar2>
	)

Both are intended to be helpful in writing constraint solvers, as well as in
other situations.

doc/reference_manual.texi:
	Document the new constructs.

library/ops.m:
	Add the keywords of the new constructs to the list of operators.
	Since they work similarly to the "some" operator, they have the same
	precedence.

compiler/hlds_goal.m:
	Replace the some(Vars, SubGoal) HLDS construct, with its optional
	keep_this_commit attribute, with the new scope(Reason, SubGoal)
	construct. The Reason argument may say that this scope is an
	existential quantification, but it can also say that it represents
	a purity promise, the introduction of a single-solution context
	with promise_equivalent_solutions, or a decision by a compiler pass.

	It can also say that the scope represents a set of goals that all arise
	from the unraveling of a unification between a variable and a ground
	term. This was intended to speed up mode checking by significantly
	reducing the number of delays and wakeups, but the cost of the scopes
	themselves turned out to be bigger than the gain in modechecking speed.

	Update the goal_path_step type to refer to scope goals instead of just
	existential quantification.

compiler/prog_data.m:
	Add new function symbols to the type we use to represent goals in items
	to stand for the new Mercury constructs.

compiler/prog_io_goal.m:
	Add code to read in the new language constructs.

compiler/prog_io_util.m:
	Add a utility predicate for use by the new code in prog_io_goal.m.

compiler/make_hlds.m:
	Convert the item representation of the new constructs to the HLDS
	representation.

	Document how the from_ground_term scope reason would work, but do not
	enable the code.

compiler/purity.m:
	When checking the purity of goals, respect the new promise_pure and
	promise_semipure scopes. Generate warnings if such scopes are
	redundant.

compiler/det_analysis.m:
	Make the insides of promise_equivalent_solutions goals single solution
	contexts.

compiler/det_report.m:
	Provide mechanisms for reporting inappropriate usage of
	promise_equivalent_solutions goals.

compiler/instmap.m:
	Add a utility predicate for use by one of the modules above.

compiler/deep_profiling.m:
	Use one of the new scope reasons to prevent simplify from optimizing
	away commits of goals that have been made impure, instead of the old
	keep_this_commit goal feature.

compiler/modes.m:
	Handle from_ground_term scopes when present; for now, they won't be
	present, since make_hlds isn't creating them.

compiler/options.m:
	Add two new compiler options, for use by implementors only, to allow
	finer control over the amount of output one gets with --debug-modes.
	(I used them when debugging the performance of the from_ground_term
	scope reason.) The options are --debug-modes-minimal and
	--debug-modes-verbose.

compiler/handle_options.m:
	Make the options that are meaningful only in the presence of
	--debug-modes imply --debug-modes, since this allows more convenient
	(shorter) invocations.

compiler/mode_debug.m:
	Respect the new options when deciding how much data to print
	when debugging of the mode checking process is enabled.

compiler/switch_detect.m:
	Rename a predicate to make it differ from another predicate by more
	than just its arity.

compiler/passes_aux.m:
	Bring this module up to date with our current style guidelines,
	by using state variable syntax where appropriate.

compiler/*.m:
	Minor changes to conform to the change in the HLDS and/or parse tree
	goal type.

mdbcomp/program_representation.m:
	Rename the some goal to the scope goal, and the same for path steps,
	to keep them in sync with the HLDS.

browser/declarative_tree.m:
	Conform to the change in goal representations.

tests/hard_coded/promise_equivalent_solutions_test.{m,exp}:
	A new test case to test the handling of the
	promise_equivalent_solutions construct.

tests/hard_coded/Mmakefile:
	Enable the new test.

tests/hard_coded/purity/promise_pure_test.{m,exp}:
	A new test case to test the handling of the promise_pure and
	promise_semipure constructs.

tests/hard_coded/purity/Mmakefile:
	Enable the new test.

tests/invalid/promise_equivalent_solutions.{m,err_exp}:
	A new test case to test the error messages for improper use of the
	promise_pure and promise_semipure constructs.

tests/invalid/Mmakefile:
	Enable the new test.
2005-03-24 05:34:41 +00:00
Zoltan Somogyi
3c60c0e485 Change a bunch of modules to import only one module per line, even
Estimated hours taken: 4
Branches: main

compiler/*.m:
	Change a bunch of modules to import only one module per line, even
	from the library.

compiler/mlds_to_il.m:
compiler/mlds_to_managed.m:
	Convert these modules to our current coding style. Use state variables
	where appropriate. Use predmode declarations where possible.
2005-03-22 06:40:32 +00:00
Zoltan Somogyi
9521818650 Get the purity check pass to not issue warnings about unnecessary purity
Estimated hours taken: 16
Branches: main

Get the purity check pass to not issue warnings about unnecessary purity
annotations on compiler-generated predicates. The problem I am addressing
is that when an optimization such as type specialization creates a clone of
a predicate, that predicate gets all the original predicate's annotations.
During the creation of a .opt file, purity checking sees the clauses of the
original predicate and knows that the annotation is not redundant, but doesn't
know that about the copy, since it has no definition at all (it doesn't need
one).

The fix is to put into each pred_info an indication of where the predicate
came from, and to never warn about unnecessary purity annotations of predicates
that the programmer didn't write.

This diff also uses the origin indication to record human-usable names of
compiler-generated or compiler-transformed predicates in RTTI for use by the
debugger.

compiler/hlds_pred.m:
	Replace two fields in pred_infos, that say (a) whether the predicate
	is a special (unify/compare/index/init) predicate and (b) whether
	it is a type class method implementation, with an origin field saying
	where the predicate came from. This field has several alternatives,
	special preds and type class method implementation being only two.

	Make the predicates that create pred_infos take an argument specifing
	where the predicate comes from.

	Replace a copy of one of the old fields in rtti_proc_labels with
	the new one.

	Make the name of the existing function more descriptive.

compiler/purity.m:
	Use the origin field to suppress unnecessary annotation warnings for
	compiler-generated predicates.

compiler/layout_out.m:
	Use the origin field to generate more human-friendly names for
	predicates, instead of the existing linker-friendly names. The
	debugger doesn't insist on predicate names being unique, even
	within a module.

compiler/*.m:
	Conform to the changed interface of hlds_pred.m. The most significant
	changes were for recording the origin of new predicates. In one case
	(dnf.m) it also involved passing the required information down to the
	place where the new predicates were created through the dnf_info tuple
	instead of separate arguments, and switching to state variable
	notation.

tests/debugger/*.exp*:
tests/debugger/declarative/*.exp*:
tests/hard_coded/*.exp*:
	Update the expected outputs to expect human-friendly predicate names.
2005-01-21 06:21:00 +00:00
Julien Fischer
a3352a6e5d Do not include :- import_module' and :- use_module' declarations
Estimated hours taken: 22
Branches: main

Do not include `:- import_module' and `:- use_module' declarations
in the implementation section of .int and .int2 files unless
the types that they export are required by the definition of
an equivalence type.  This should help prevent unnecessary
recompilations when new imports are made in the implementation
of modules.

Break up check_hlds.type_util so that predicates that do
not require access to the HLDS are placed in a new module,
parse_tree.prog_type.  The above change requires some of
these predicates.  This also removes one of the dependencies
between the parse_tree package on modules of the check_hlds
package.

Remove the remaining such dependency by moving
inst_constrains_unconstrained_var/1 from check_hlds.inst_util
to parse_tree.prog_mode.  None of the modules in parse_tree
now depend upon modules in check_hlds.

Modify the parser so that import_module declarations
that specify more than one module are replaced by multiple
import_module declarations, with one module per declaration.
This makes the above change easier to implement and is in
any case required by the upcoming diff for canonicalizing
module interfaces.  We also do the same for use_module and
include_module declarations.

compiler/modules.m:
	Don't import modules in the implementation section
	of interface files unless they are required by the
	definition of equivalence types.

compiler/prog_type.m:
	New module.  Move procedures from type_util that do
	not depend on the HLDS to here so that we can use them
	when generating interface files.

	XXX There are probably others that could be moved as
	well - I only moved those that were immediately useful.

compiler/type_util.m:
	Delete the procedures that have been moved to the
	new prog_type module.

compiler/prog_io.m:
	Remove the dependency on check_hlds.inst_util.

compiler/prog_io_typeclass.m:
compiler/equiv_type.m:
	Remove dependencies on check_hlds.type_util.

compiler/prog_util.m:
	Add a predicate sym_name_get_module_name/2 that is
	similar to sym_name_get_module_name/3 except that it
	fails if the input is an unqualified sym_name.

compiler/inst_util.m:
	Delete inst_contains_unconstrained_var/1 from this
	module and copy it to prog_mode.m.

compiler/parse_tree.m:
	Include the new module.

	Do not import the check_hlds package as all dependencies
	on this package have been removed.

compiler/*.m:
	Minor changes to conform to the above.

compiler/notes/compiler_design.html:
	Mention the new module.
2005-01-21 03:27:58 +00:00
Peter Wang
59d2d4a573 This adds a module mdbcomp__trace_counts that reads in the
Estimated hours taken: 17
Branches: main

This adds a module mdbcomp__trace_counts that reads in the
.mercury_trace_counts files produced by the compiler's trace mechanism.
The format of said files was slightly changed.

As the new module is to be used by the compiler and the debugger, it is
placed in the mdbcomp module.  This required bringing some types from the
compiler into a new module within mdbcomp.

browser/trace_counts.m:
	New module for reading execution trace summaries.

browser/prim_data.m:
	New module holding types and predicates moved in from the compiler.
	Types:
		pred_or_func, sym_name, module_name, proc_label,
		special_pred_id, trace_port
	Predicates:
		string_to_sym_name, insert_module_qualifier

	The mode field of proc_label is now an int instead of a proc_id
	to avoid pulling proc_id into mdbcomp.

browser/mdbcomp.m:
	Add trace_counts and prim_data to the mdbcomp module.

browser/declarative_execution.m:
	Renamed mdb's definition of module_name to flat_module_name
	to avoid conflicts with the definition in mdbcomp__prim_data.

runtime/mercury_trace_base.c:
	In the format of .mercury_trace_counts, write module and predicate
	names now use quoted atom syntax so that names with spaces and
	non-printable characters can be machine-parsed.

browser/:
compiler/:
	Many changes to account for movement of types, and the change to
	proc_label.
2005-01-19 03:11:22 +00:00