Commit Graph

123 Commits

Author SHA1 Message Date
Zoltan Somogyi
c31be3d6ac Fix a limitation: recognize switches in which *all* arms contain
Estimated hours taken: 0.5
Branches: main

compiler/switch_detection.m:
	Fix a limitation: recognize switches in which *all* arms contain
	not a single unification of the switched-on variable but a disjunction
	of such unifications.

	Fix some misleading variable names.

tests/hard_coded/disjs_in_switch.{m,exp}:
	Add a test case for this bug.

tests/hard_coded/Mmakefile:
	Enable the new test case.
2006-04-07 01:32:58 +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
25b8b1abc3 Fix several performance bugs that showed up when the compiler was invoked on
Estimated hours taken: 20
Branches: main

Fix several performance bugs that showed up when the compiler was invoked on
Douglas Auclair's training_cars example. Also fix some minor problems that
made it harder to find the information needed to localize those problems.

training_cars.m is hard to compile quickly because it is big in two dimensions:
it has lots of clauses, and each clause has big terms.

My laptop still tries to swap itself to death on the full version of
training_cars.m (it has only 512 Mb), but the compiler now works fine
on a version containing about 20% of its clauses, whereas previously
it couldn't compile it at all.

In most cases, the changes convert N^2 algorithms to NlogN algorithms.
They probably have higher constant factors and may yield small slowdowns
for small N, but this is probably not noticeable. Avoiding bad worst case
behavior is more important.

compiler/superhomogeneous.m:
	Record the number of goals inserted in each goal being converted
	to superhomogeneous form. If this exceeds a threshold, wrap a
	from_ground_term scope around it.

	Put the predicates into a more cohesive sequence.

compiler/field_access.m:
	Work with the code in superhomogeneous to record the number of inserted
	goals. Reorder the arguments of some performances to be consistent
	with the predicates in superhomogeneous.m.

compiler/modes.m:
	Use the from_ground_term scope to reverse the list of inserted
	unifications if necessary. It is much more efficient to do this here
	than to let it happen by sequences of delays and wakeups. That would
	have quadratic complexity; this is linear.

	This is what I originally introduced from_ground_term scopes for.
	Then, the overhead was too high, because I added one scope per function
	symbol. This version should be fine, since there is at most one scope
	added per argument of an atom (clause head or call).

compiler/modes.m:
compiler/unique_modes.m:
	When we are processing goals inside a from_ground_term scope, record
	this fact.

compiler/mode_info.m:
	Make it possible to record this fact.

compiler/modecheck_unify.m:
	When we are inside a from_ground_term scope, don't try to update the
	insts of vars on the right hand sides of construction unifications.
	Since these variables came from expansion to superhomogeneous form,
	those variables won't occur in any following code, so updating their
	state is useless, and the algorithm we used to do so is linear in the
	size of the inst. Since the size of an inst of a variable that results
	from superhomogeneous expansion is itself on average proportional to
	the size of the original term, this change turns a quadratic algorithm
	into a linear one.

compiler/inst_match.m:
	Use balanced trees instead of ordered lists to represents sets of
	expansions, since these sets can be large.

	Note an opportunity for further improvement.

compiler/inst_util.m:
	Note another opportunity for further improvement.

compiler/instmap.m:
	Rename several predicates to avoid ambiguities.

compiler/cse_detection.m:
	We used to print statistics for the processing of each procedure
	without saying which procedure it is for; fix this.

compiler/switch_detection.m:
	Don't print progress messages for predicates with no procedures,
	since they would be misleading.

compiler/higher_order.m:
	Change an algorithm that was quadratic in the number of arms
	for merging the information from the different arms of disjunctions
	and switches to an NlogN algorithm.

	Change the algorithm for merging the info from two branches
	that quadratic in the number of variables per arm to an NlogN
	algorithm.

	Changed some type equivalences to notag types to aid robustness.

compiler/quantification.m:
	Rename several predicates to avoid ambiguities.

	The sets of variables in different arms of disjunctions and switches
	tend to have relatively small intersections. Yet the algorithms we
	used to compute the set of variables free in the disjunction or switch
	included the variables from the already processed arms in the sets
	being accumulated when processing later arms, leading to the quadratic
	behavior. This diff changes the algorithm to process each arm
	independently, and then use a more balanced algorithm to summarize
	the result.

	Specialize the predicates that compute sets of free vars in various
	HLDS fragments to work either with ordinary_nonlocals or
	code_gen_nonlocals without making the same decision repeatedly.

	Move some code out of large predicates into predicates of their own.

compiler/Mercury.options:
	Specify the compiler option that can exploit this specialization
	to make the code run faster.

compiler/simplify.m:
	Use a more efficient data structure for recording the parameters
	of an invocation of simplification.

	Change some predicate names and function symbol names to avoid
	ambiguity.

compiler/common.m:
compiler/deforest.m:
compiler/deforest.m:
compiler/make_hlds_warn.m:
compiler/mercury_compile.m:
compiler/pd_util.m:
compiler/stack_opt.m:
compiler/term_constr_build.m:
	Conform to the changes in simplify.m and/or instmap.m.

compiler/mercury_compile.m:
	Fix a bug in progress messages for polymorphism.m.

compiler/equiv_type_hlds.m:
	Most of the time, substitutions inside insts have no effect, because
	very few insts include any reference to a types. Instead of the old
	approach of building new insts and then throwing them away if they
	are the same as the old ones, don't build new insts at all if the
	old inst contains no types.

compiler/common.m:
	Change some predicate names to make them clearer.

compiler/hlds_clauses.m:
	Record the number of clauses so far, to allow a more informative
	progress message to be printed.

compiler/add_clause.m:
	Print this more informative progress message.

	Conform to the changes in superhomogeneous.m.

compiler/code_gen.m:
	Use the context of the predicate's first clause (which will be the
	context of the first clause head) as the context of the predicate's
	interface events. Unlike the context of the body goal, this won't
	be affected by program transformations such as wrapping a
	from_ground_term scope around some goals. It is better for users
	anyway, since the old policy lead to contexts in the middle of
	procedure bodies if the top level goal was a disjunction, switch or
	if-then-else.

tests/debugger/*.exp:
	Update the expected outputs to conform to the change to code_gen.m.
2006-03-29 00:57:46 +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
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
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
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
2cd2009971 Allow the detection of switches in which some disjuncts start not
Estimated hours taken: 2
Branches: main

compiler/switch_detect.m:
	Allow the detection of switches in which some disjuncts start not
	with a unification, but with disjunction of unifications. In such
	cases, the rest of the disjunct is duplicated for all the switch arms
	we can create.

compiler/hard_coded/switch_detect.{m,inp,exp}:
	New test case to test the new functionality.

compiler/hard_coded/Mmakefile:
	Enable the new test case.
2005-09-02 05:00:29 +00:00
Zoltan Somogyi
c1410663a9 Convert to four-space indentation.
Estimated hours taken: 0.1
Branches: main

compiler/switch_detection.m:
	Convert to four-space indentation.
2005-09-02 00:36:04 +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
394725a875 Fix a limitation of switch detection and common subexpression elimination.
Estimated hours taken: 4
Branches: main, release

Fix a limitation of switch detection and common subexpression elimination.
The limitation was that when they looked for deconstruction unifications,
they stopped looking when encountering a call, even if the call came from
the clause head.

compiler/hlds_goal.m:
	Add a goal feature denoting that the goal came from the clause head.

compiler/goal_util.m:
	Add a predicate for attaching goal features to all subgoals of a goal.

compiler/make_hlds.m:
	Use the predicate in goal_util.m to mark goals that came from the
	clause head.

compiler/switch_detection.m:
	Make the predicate used by both switch detection and common
	subexpression elimination use the new goal feature to look past
	goals that came from the clause head.

	Make the relevant predicates use state variables better.

compiler/hlds_out.m:
	Print out goal features even for goals in clause_infos, since there
	is now a goal feature that makes sense in such goals. Make the code
	for computing the set of annotations we print in clauses more
	maintainable.

compiler/saved_vars.m:
	Handle the new goal feature.

tests/valid/func_in_head.m:
	New test case to test the fix.

tests/valid/Mmakefile:
	Enable the new test case.
2005-02-15 00:04:59 +00:00
Julien Fischer
a7a52527dd Replace deprecated syntax for :- inst and :- mode
Estimated hours taken: 0.5
Branches: main

compiler/accumulator.m:
compiler/make_hlds.m:
compiler/ml_code_util.m:
compiler/mlds_to_c.m:
compiler/passes_aux.m:
compiler/pd_info.m:
compiler/rl_analyse.m:
compiler/rl_info.m:
compiler/switch_detection.m:
compiler/typecheck.m:
	Replace deprecated syntax for :- inst and :- mode
	declarations.
2004-07-20 16:06:40 +00:00
Zoltan Somogyi
d332038ee1 Bring these modules up to date with our coding guidelines.
Estimated hours taken: 16
Branches: main

compiler/aditi_builtin_ops.m:
compiler/bytecode.m:
compiler/bytecode_backend.m:
compiler/bytecode_gen.m:
compiler/c_util.m:
compiler/code_gen.m:
compiler/deep_profiling.m:
compiler/deforest.m:
compiler/dependency_graph.m:
compiler/fact_table.m:
compiler/follow_code.m:
compiler/handle_options.m:
compiler/hlds_out.m:
compiler/il_peephole.m:
compiler/ilasm.m:
compiler/java_util.m:
compiler/liveness.m:
compiler/magic.m:
compiler/magic_util.m:
compiler/make.dependencies.m:
compiler/make.m:
compiler/make.module_dep_file.m:
compiler/make.program_target.m:
compiler/make.util.m:
compiler/matching.m:
compiler/name_mangle.m:
compiler/opt_debug.m:
compiler/opt_util.m:
compiler/options.m:
compiler/options_file.m:
compiler/prog_io.m:
compiler/rtti_out.m:
compiler/rtti_to_mlds.m:
compiler/saved_vars.m:
compiler/source_file_map.m:
compiler/stack_alloc.m:
compiler/stack_layout.m:
compiler/stratify.m:
compiler/switch_detection.m:
compiler/term_errors.m:
compiler/type_ctor_info.m:
compiler/unify_proc.m:
compiler/unique_modes.m:
	Bring these modules up to date with our coding guidelines. Use predmode
	syntax for declarations. Use state variable syntax where appropriate,
	and reorder arguments where this is needed for the use of state
	variable syntax. Remove module qualification from the names of defined
	predicates when the module qualification was used inconsistently
	(causing problems for the use of tags) or was causing problems with
	indentation.

	There are no changes in algorithms.
2004-06-30 02:48:20 +00:00
Zoltan Somogyi
885fd4a387 Remove almost all dependencies by the modules of parse_tree.m on the modules
Estimated hours taken: 12
Branches: main

Remove almost all dependencies by the modules of parse_tree.m on the modules
of hlds.m. The only such dependencies remaining now are on type_util.m.

compiler/hlds_data.m:
compiler/prog_data.m:
	Move the cons_id type from hlds_data to prog_data, since several parts
	of the parse tree data structure depend on it (particularly insts).
	Remove the need to import HLDS modules in prog_data.m by making the
	cons_ids that refer to procedure ids refer to them via a new type
	that contains shrouded pred_ids and proc_ids. Since pred_ids and
	proc_ids are abstract types in hlds_data, add predicates to hlds_data
	to shroud and unshroud them.

	Also move some other types, e.g. mode_id and class_id, from hlds_data
	to prog_data.

compiler/hlds_data.m:
compiler/prog_util.m:
	Move predicates for manipulating cons_ids from hlds_data to prog_util.

compiler/inst.m:
compiler/prog_data.m:
	Move the contents of inst.m to prog_data.m, since that is where it
	belongs, and since doing so eliminates a circular dependency.
	The separation doesn't serve any purpose any more, since we don't
	need to import hlds_data.m anymore to get access to the cons_id type.

compiler/mode_util.m:
compiler/prog_mode.m:
compiler/parse_tree.m:
	Move the predicates in mode_util that don't depend on the HLDS to a new
	module prog_mode, which is part of parse_tree.m.

compiler/notes/compiler_design.m:
	Mention prog_mode.m, and delete the mention of inst.m.

compiler/mercury_to_mercury.m:
compiler/hlds_out.m:
	Move the predicates that depend on HLDS out of mercury_to_mercury.m
	to hlds_out.m. Export from mercury_to_mercury.m the predicates needed
	by the moved predicates.

compiler/hlds_out.m:
compiler/prog_out.m:
	Move predicates for printing parts of the parse tree out of hlds_out.m
	to prog_out.m, since mercury_to_mercury.m needs to use them.

compiler/purity.m:
compiler/prog_out.m:
	Move predicates for printing purities from purity.m, which is part
	of check_hlds.m, to prog_out.m, since mercury_to_mercury.m needs to use
	them.

compiler/passes_aux.m:
compiler/prog_out.m:
	Move some utility predicates (e.g. for printing progress messages) from
	passes_aux.m to prog_out.m, since some predicates in submodules of
	parse_tree.m need to use them.

compiler/foreign.m:
compiler/prog_data.m:
	Move some types from foreign.m to prog_data.m to allow the elimination
	of some dependencies on foreign.m from submodules of parse_tree.m.

compiler/*.m:
	Conform to the changes above, mostly by updating lists of imported
	modules and module qualifications. In some cases, also do some local
	cleanups such as converting predicate declarations to predmode syntax
	and fixing white space.
2004-06-14 04:17:03 +00:00
Zoltan Somogyi
7bf0cd03af Reduce the overhead of all forms of tabling by eliminating in many cases
Estimated hours taken: 32
Branches: main

Reduce the overhead of all forms of tabling by eliminating in many cases
the overhead of transferring data across the C/Mercury boundary. These
involve lots of control transfers as well as assignments to and from
Mercury abstract machine registers, which are not real machine registers
on x86 machines. Benchmarking in Uppsala revealed this overhead to be
a real problem.

The way we do that is by changing the tabling transformation so that instead
of generating sequences of calls to predicates from library/table_builtin.m,
we generate sequences of calls to C macros from runtime/mercury_tabling_pred.h,
and emit the resulting code string as the body of a foreign_proc goal.
(The old transformation is still available via a new option,
--no-tabling-via-extra-args.)

Since the number of inputs and outputs of the resulting C code sequences
are not always fixed (they can depend on the number of input or output
arguments of predicate being transformed), implementing this required
adding to foreign_procs a new field that allows the specification of extra
arguments to be passed to and from the given foreign code fragment. For now,
this mechanism is implemented only by the C backends, since it is needed
only by the C backends. (We don't support yet tabling on other backends.)

To simplify the new implementation of the field on foreign_procs, consolidate
three existing fields into one. Each of these fields was a list with one
element per argument, so turning them into a single list with a combined record
per argument should also improve reliability, since it reduces the likelyhood
of updates leaving the data structure inconsistent.

The goal paths of components of a tabled predicate depend on whether
-no-tabling-via-extra-args was specified. To enable the expected outputs
of the debugger test cases testing tabling, we add a new mdb command,
goal_paths, that controls whether goal paths are printed by the debugger
at events, and turn off the printing of events in the relevant test cases.

Also, prepare for a future change to optimize the trie structure for
user-defined types by handling type_infos (and once we support them,
typeclass_infos) specially.

compiler/table_gen.m:
	Change the tabling transformation along the lines described above.

	To allow us to factor out as much of the new code as possible,
	we change the meaning of the call_table_tip variable for minimal
	model subgoals: instead of the trie node at the end of the answer
	table, it is not now the subgoal reachable from it. This change
	has no effect as yet, because we use call_table_tip variables
	only to perform resets across retries in the debugger, and we
	don't do retries across calls to minimal model tabled predicates.

	Put predicates into logical groups.

library/table_builtin.m:
runtime/mercury_tabling_preds.h:
	When the new transformations in table_gen.m generate foreign_procs
	with variable numbers of arguments, the interfaces of those
	foreign_procs often do not match the interfaces of the existing
	library predicates at their core: they frequently have one more
	or one fewer argument. To prevent any possible confusion, in such
	cases we add a new variant of the predicate. These predicates
	have the suffix _shortcut in their name. Their implementations
	are dummy macros that do nothing; they serve merely as placeholders
	before or after which the macros that actually do the work are
	inserted.

	Move the definitions of the lookup, save and restore predicates
	into mercury_tabling_preds.h. Make the naming scheme of their
	arguments more regular.

runtime/mercury_minimal_model.c:
runtime/mercury_tabling_preds.h:
	Move the definition of a predicate from mercury_minimal_model.c
	to mercury_tabling_preds.h, since the compiler now needs to be
	able to generate an inlined version of it.

compiler/hlds_goal.m:
	Replace the three existing fields describing the arguments of
	foreign_procs with one, and add a new field describing the extra
	arguments that may be inserted by table_gen.m.

	Add utility predicates for processing the arguments of foreign_procs.

	Change the order of some existing groups of declarations make it
	more logical.

compiler/hlds_pred.m:
runtime/mercury_stack_layout.h:
	Extend the data structures recording the structure of tabling tries
	to allow the representation of trie steps for type_infos and
	typeclass_infos.

runtime/mercury_tabling_macros.c:
	Fix a bug regarding the tabling of typeclass_infos, which is now
	required for a clean compile.

compiler/pragma_c_gen.m:
compiler/ml_code_gen.m:
	Modify the generation of code for foreign_procs to handle extra
	arguments, and to conform to the new data structures for foreign_proc
	arguments.

compiler/llds.m:
	The tabling transformations can now generate significantly sized
	foreign_procs bodies, which the LLDS code generator translates to
	pragma_c instructions. Duplicating these by jump optimization
	may lose more by worsening locality than it gains in avoiding jumps,
	so we add an extra field to pragma_c instructions that tells jumpopt
	not to duplicate code sequences containing such pragma_cs.

compiler/jumpopt.m:
	Respect the new flag on pragma_cs.

compiler/goal_util.m:
	Add a predicate to create foreign_procs with specified contents,
	modelled on the existing predicate to create calls.

	Change the order of the arguments of that existing predicate
	to make it more logical.

compiler/polymorphism.m:
	Conform to the new definition of foreign_procs. Try to simplify
	the mechanism for generating the type_info and typeclass_info
	arguments of foreign_proc goals, but it is not clear that this
	code is even ever executed.

compiler/aditi_builtin_ops.m:
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/deep_profiling.m:
compiler/deforest.m:
compiler/delay_construct.m:
compiler/dependency_graph.m:
compiler/det_analysis.m:
compiler/det_report.m:
compiler/dnf.m:
compiler/dupelim.m:
compiler/equiv_type_hlds.m:
compiler/exprn_aux.m:
compiler/follow_code.m:
compiler/follow_vars.m:
compiler/frameopt.m:
compiler/goal_form.m:
compiler/goal_path.m:
compiler/higher_order.m:
compiler/higher_order.m:
compiler/hlds_module.m:
compiler/hlds_out.m:
compiler/inlining.m:
compiler/ite_gen.m:
compiler/layout_out.m:
compiler/livemap.m:
compiler/liveness.m:
compiler/llds_out.m:
compiler/loop_inv.m:
compiler/magic.m:
compiler/make_hlds.m:
compiler/mark_static_terms.m:
compiler/middle_rec.m:
compiler/modes.m:
compiler/modules.m:
compiler/opt_debug.m:
compiler/pd_cost.m:
compiler/prog_rep.m:
compiler/purity.m:
compiler/quantification.m:
compiler/reassign.m:
compiler/rl_exprn.m:
compiler/saved_vars.m:
compiler/simplify.m:
compiler/size_prof.m:
compiler/store_alloc.m:
compiler/stratify.m:
compiler/switch_detection.m:
compiler/term_pass1.m:
compiler/term_traversal.m:
compiler/termination.m:
compiler/trace.m:
compiler/typecheck.m:
compiler/unify_proc.m:
compiler/unique_modes.m:
compiler/unneeed_code.m:
compiler/unused_args.m:
compiler/use_local_vars.m:
	Conform to the new definition of foreign_procs, pragma_cs and/or
	table trie steps, or to changed argument orders.

compiler/add_heap_ops.m:
compiler/add_trail_ops.m:
compiler/cse_detection.m:
compiler/dead_proc_elim.m:
compiler/equiv_type.m:
compiler/intermod.m:
compiler/lambda.m:
compiler/lco.m:
compiler/module_util.m:
compiler/opt_util.m:
compiler/stack_opt.m:
compiler/trans_opt.m:
	Conform to the new definition of foreign_procs.

	Bring these modules up to date with our current code style guidelines,
	using predmode declarations, state variable syntax and unification
	expressions as appropriate.

compiler/mercury_compile.m:
	Conform to the changed argument order of a predicate in trans_opt.m.

compiler/options.m:
	Add the --no-tabling-via-extra-args option, but leave the
	documentation commented out since the option is for developers only.

doc/user_guide.texi:
	Document --no-tabling-via-extra-args option, though leave the
	documentation commented out since the option is for developers only.

doc/user_guide.texi:
doc/mdb_categories:
	Document the new goal_paths mdb command.

trace/mercury_trace_internals.c:
	Implement the new goal_paths mdb command.

tests/debugger/completion.exp:
	Conform to the presence of the goal_paths mdb command.

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

tests/debugger/print_table.{inp,exp*}:
tests/debugger/retry.{inp,exp*}:
	Use the goal_paths command to avoid having the expected output
	depend on the presence or absence of --tabling-via-extra-args.

tests/tabling/table_foreign_output.{m,exp}:
	Add a new test case to test the save/restore of arguments of foreign
	types.

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

tests/tabling/test_tabling:
	Make this script more robust.

	Add an option for testing only the standard model forms of tabling.
2004-06-07 09:07:23 +00:00
Zoltan Somogyi
2f1d4d2dd7 Bring this module up to date with our current coding standards.
Estimated hours taken: 0.3
Branches: main

compiler/switch_detection.m:
	Bring this module up to date with our current coding standards.
	Use predmode declarations, state variable syntax and field accesses
	as relevant. Reorder arguments where this allows the use of state
	variable syntax. There are no changes in algorithms.

compiler/hlds_goal.m:
	Add field names to unify_rhs, to allow simplification of code in
	switch_detection.m.
2004-02-20 01:58:50 +00:00
Zoltan Somogyi
b39a3d855f This diff makes hlds_module.m and many callers of its predicates easier to read
Estimated hours taken: 6
Branches: main

This diff makes hlds_module.m and many callers of its predicates easier to read
and to maintain, but contains no changes in algorithms whatsoever.

compiler/hlds_module.m:
	Bring (most of) this module into line with our current coding
	standards. Use predmode declarations, functions, and state variable
	syntax when appropriate. (The 'most of' is because I left the part of
	the module dealing with predicate tables alone, not wishing to cause
	a conflict for Pete.)

	Reorder arguments of predicates where necessary for the use of state
	variable syntax, and where this improves readability.

	Replace old-style lambdas with new-style lambdas or with partially
	applied named procedures.

compiler/*.m:
	Conform to the changes in hlds_module.m. This mostly means using the
	new argument orders of predicates exported by hlds_module.m, and
	switching to state variable notation.

	Replace old-style lambdas with new-style lambdas or with partially
	applied named procedures in updated code.

	Replace unnecessary occurrences of four-space indentation with
	standard indentation in updated code.

library/list.m:
library/map.m:
library/tree234.m:
	Add list__foldl4 and map__foldl3, since in some compiler modules,
	state variable notation is more convenient (and the code more
	efficient) if we don't have to bundle up several data structures
	into a tuple just to iterate over them.

	Change the fold predicates to use state variable notation.

NEWS:
	Mention the new library functions.
2003-10-31 03:27:39 +00:00
Zoltan Somogyi
8693e293a2 This diff makes hlds_pred.m and many callers of its predicates easier to read
Estimated hours taken: 4
Branches: main

This diff makes hlds_pred.m and many callers of its predicates easier to read
and to maintain, but contains no changes in algorithms whatsoever.

compiler/hlds_pred.m:
	Bring this module into line with our current coding standards.
	Use predmode declarations, functions, and state variable syntax
	when appropriate.

	Reorder arguments of predicates where necessary for the use of state
	variable syntax, and where this improves readability.

	Replace old-style lambdas with new-style lambdas or with partially
	applied named procedures.

	Standardize indentation.

compiler/*.m:
	Conform to the changes in hlds_pred.m. This mostly means using the
	new argument orders of predicates exported by hlds_pred.m. Where this
	is now conveniently possible, change predicates to use state
	variable notation.

	In some modules, using state variable notation required changing the
	orders of arguments in the module's top predicate.

compiler/passes_aux.m:
	Change the order of arguments in the calls this module makes to
	allow the callees to use state variable notation.

	Convert this module to state variable notation too.
2003-10-24 06:17:51 +00:00
Zoltan Somogyi
9551640f55 Import only one compiler module per line. Sort the blocks of imports.
Estimated hours taken: 2
Branches: main

compiler/*.m:
	Import only one compiler module per line. Sort the blocks of imports.
	This makes it easier to merge in changes.

	In a couple of places, remove unnecessary imports.
2003-03-15 03:09:14 +00:00
Fergus Henderson
ef7ed9c2f5 Support impurity declarations for higher-order code.
Estimated hours taken: 24
Branches: main

Support impurity declarations for higher-order code.

In particular, allow `impure' and `semipure' annotations on
higher-order types, higher-order calls, and lambda expresions.

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

compiler/hlds_goal.m:
compiler/hlds_pred.m:
	Add `purity' field to
	- the `higher_order' alternative of the hlds_goal.generic_call type
	- the `higher_order' alternative of the hlds_pred.generic_call_id type
	- the `lambda_goal' alternative of the hlds_goal.unify_rhs type

compiler/type_util.m:
	Add a new `purity' argument to the procedures dealing with
	higher-order types.  Add code for parsing impure/semipure
	higher-order types.

compiler/lambda.m:
compiler/make_hlds.m:
compiler/typecheck.m:
compiler/post_typecheck.m:
compiler/purity.m:
compiler/polymorphism.m:
	Various minor changes to support impure/semipure higher-order lambda
	expressions.

compiler/polymorphism.m:
compiler/pseudo_type_info.m:
	XXX ought to change these to include purity in the RTTI for
	higher-order function types.

compiler/simplify.m:
	Don't try to optimize semipure/impure higher-order calls.

compiler/assertion.m:
compiler/bytecode_gen.m:
compiler/call_gen.m:
compiler/continuation_info.m:
compiler/cse_detection.m:
compiler/dead_proc_elim.m:
compiler/deep_profiling.m:
compiler/det_analysis.m:
compiler/det_util.m:
compiler/equiv_type.m:
compiler/goal_util.m:
compiler/higher_order.m:
compiler/hlds_out.m:
compiler/intermod.m:
compiler/magic.m:
compiler/magic_util.m:
compiler/ml_call_gen.m:
compiler/ml_closure_gen.m:
compiler/mode_util.m:
compiler/modecheck_call.m:
compiler/modecheck_unify.m:
compiler/modes.m:
compiler/module_qual.m:
compiler/pd_util.m:
compiler/prog_rep.m:
compiler/pseudo_type_info.m:
compiler/quantification.m:
compiler/recompilation.usage.m:
compiler/rl_gen.m:
compiler/stratify.m:
compiler/switch_detection.m:
compiler/term_traversal.m:
compiler/term_util.m:
compiler/unify_gen.m:
compiler/unique_modes.m:
	Trivial changes to handle the new purity fields and/or arguments.

tests/hard_coded/purity/Mmakefile:
tests/hard_coded/purity/impure_func_t5_fixed2.m:
tests/hard_coded/purity/impure_func_t5_fixed2.exp:
tests/hard_coded/purity/impure_func_t5_fixed2.exp2:
tests/hard_coded/purity/impure_pred_t1_fixed3.m:
tests/hard_coded/purity/impure_pred_t1_fixed3.exp:
tests/invalid/purity/Mmakefile:
tests/invalid/purity/impure_func_t5_fixed.m:
tests/invalid/purity/impure_func_t5_fixed.err_exp:
tests/invalid/purity/impure_pred_t1_fixed.m:
tests/invalid/purity/impure_pred_t1_fixed.err_exp:
	Add new test cases to test the new feature.

tests/invalid/purity/impure_func_t5.err_exp:
tests/invalid/purity/impure_pred_t1.err_exp:
tests/invalid/purity/impure_pred_t2.err_exp:
tests/invalid/purity/purity.err_exp:
tests/invalid/purity/purity_nonsense.err_exp:
	Update the expected error messages for existing test cases.

tests/invalid/purity/.cvsignore:
	New file, copied from tests/invalid/.cvsignore.
2003-01-27 09:21:03 +00:00
Zoltan Somogyi
189b9215ae This diff implements stack slot optimization for the LLDS back end based on
Estimated hours taken: 400
Branches: main

This diff implements stack slot optimization for the LLDS back end based on
the idea that after a unification such as A = f(B, C, D), saving the
variable A on the stack indirectly also saves the values of B, C and D.

Figuring out what subset of {B,C,D} to access via A and what subset to access
via their own stack slots is a tricky optimization problem. The algorithm we
use to solve it is described in the paper "Using the heap to eliminate stack
accesses" by Zoltan Somogyi and Peter Stuckey, available in ~zs/rep/stackslot.
That paper also describes (and has examples of) the source-to-source
transformation that implements the optimization.

The optimization needs to know what variables are flushed at call sites
and at program points that establish resume points (e.g. entries to
disjunctions and if-then-elses). We already had code to compute this
information in live_vars.m, but this code was being invoked too late.
This diff modifies live_vars.m to allow it to be invoked both by the stack
slot optimization transformation and by the code generator, and allows its
function to be tailored to the requirements of each invocation.

The information computed by live_vars.m is specific to the LLDS back end,
since the MLDS back ends do not (yet) have the same control over stack
frame layout. We therefore store this information in a new back end specific
field in goal_infos. For uniformity, we make all the other existing back end
specific fields in goal_infos, as well as the similarly back end specific
store map field of goal_exprs, subfields of this new field. This happens
to significantly reduce the sizes of goal_infos.

To allow a more meaningful comparison of the gains produced by the new
optimization, do not save any variables across erroneous calls even if
the new optimization is not enabled.

compiler/stack_opt.m:
	New module containing the code that performs the transformation
	to optimize stack slot usage.

compiler/matching.m:
	New module containing an algorithm for maximal matching in bipartite
	graphs, specialized for the graphs needed by stack_opt.m.

compiler/mercury_compile.m:
	Invoke the new optimization if the options ask for it.

compiler/stack_alloc.m:
	New module containing code that is shared between the old,
	non-optimizing stack slot allocation system and the new, optimizing
	stack slot allocation system, and the code for actually allocating
	stack slots in the absence of optimization.

	Live_vars.m used to have two tasks: find out what variables need to be
	saved on the stack, and allocating those variables to stack slots.
	Live_vars.m now does only the first task; stack_alloc.m now does
	the second, using code that used to be in live_vars.m.

compiler/trace_params:
	Add a new function to test the trace level, which returns yes if we
	want to preserve the values of the input headvars.

compiler/notes/compiler_design.html:
	Document the new modules (as well as trace_params.m, which wasn't
	documented earlier).

compiler/live_vars.m:
	Delete the code that is now in stack_alloc.m and graph_colour.m.

	Separate out the kinds of stack uses due to nondeterminism: the stack
	slots used by nondet calls, and the stack slots used by resumption
	points, in order to allow the reuse of stack slots used by resumption
	points after execution has left their scope. This should allow the
	same stack slots to be used by different variables in the resumption
	point at the start of an else branch and nondet calls in the then
	branch, since the resumption point of the else branch is not in effect
	when the then branch is executed.

	If the new option --opt-no-return-calls is set, then say that we do not
	need to save any values across erroneous calls.

	Use type classes to allow the information generated by this module
	to be recorded in the way required by its invoker.

	Package up the data structures being passed around readonly into a
	single tuple.

compiler/store_alloc.m:
	Allow this module to be invoked by stack_opt.m without invoking the
	follow_vars transformation, since applying follow_vars before the form
	of the HLDS code is otherwise final can be a pessimization.

	Make the module_info a part of the record containing the readonly data
	passed around during the traversal.

compiler/common.m:
	Do not delete or move around unifications created by stack_opt.m.

compiler/call_gen.m:
compiler/code_info.m:
compiler/continuation_info.m:
compiler/var_locn.m:
	Allow the code generator to delete its last record of the location
	of a value when generating code to make an erroneous call, if the new
	--opt-no-return-calls option is set.

compiler/code_gen.m:
	Use a more useful algorithm to create the messages/comments that
	we put into incr_sp instructions, e.g. by distinguishing between
	predicates and functions. This is to allow the new scripts in the
	tool directory to gather statistics about the effect of the
	optimization on stack frame sizes.

library/exception.m:
	Make a hand-written incr_sp follow the new pattern.

compiler/arg_info.m:
	Add predicates to figure out the set of input, output and unused
	arguments of a procedure in several different circumstances.
	Previously, variants of these predicates were repeated in several
	places.

compiler/goal_util.m:
	Export some previously private utility predicates.

compiler/handle_options.m:
	Turn off stack slot optimizations when debugging, unless
	--trace-optimized is set.

	Add a new dump format useful for debugging --optimize-saved-vars.

compiler/hlds_llds.m:
	New module for handling all the stuff specific to the LLDS back end
	in HLDS goal_infos.

compiler/hlds_goal.m:
	Move all the relevant stuff into the new back end specific field
	in goal_infos.

compiler/notes/allocation.html:
	Update the documentation of store maps to reflect their movement
	into a subfield of goal_infos.

compiler/*.m:
	Minor changes to accomodate the placement of all back end specific
	information about goals from goal_exprs and individual fields of
	goal_infos into a new field in goal_infos that gathers together
	all back end specific information.

compiler/use_local_vars.m:
	Look for sequences in which several instructions use a fake register
	or stack slot as a base register pointing to a cell, and make those
	instructions use a local variable instead.

	Without this, a key assumption of the stack slot optimization,
	that accessing a field in a cell costs only one load or store
	instruction, would be much less likely to be true. (With this
	optimization, the assumption will be false only if the C compiler's
	code generator runs out of registers in a basic block, which for
	the code we generate should be unlikely even on x86s.)

compiler/options.m:
	Make the old option --optimize-saved-vars ask for both the old stack
	slot optimization (implemented by saved_vars.m) that only eliminates
	the storing of constants in stack slots, and the new optimization.

	Add two new options --optimize-saved-vars-{const,cell} to turn on
	the two optimizations separately.

	Add a bunch of options to specify the parameters of the new
	optimizations, both in stack_opt.m and use_local_vars.m. These are
	for implementors only; they are deliberately not documented.

	Add a new option, --opt-no-return-cells, that governs whether we avoid
	saving variables on the stack at calls that cannot return, either by
	succeeding or by failing. This is for implementors only, and thus
	deliberately documented only in comments. It is enabled by default.

compiler/optimize.m:
	Transmit the value of a new option to use_local_vars.m.

doc/user_guide.texi:
	Update the documentation of --optimize-saved-vars.

library/tree234.m:
	Undo a previous change of mine that effectively applied this
	optimization by hand. That change complicated the code, and now
	the compiler can do the optimization automatically.

tools/extract_incr_sp:
	A new script for extracting stack frame sizes and messages from
	stack increment operations in the C code for LLDS grades.

tools/frame_sizes:
	A new script that uses extract_incr_sp to extract information about
	stack frame sizes from the C files saved from a stage 2 directory
	by makebatch and summarizes the resulting information.

tools/avg_frame_size:
	A new script that computes average stack frame sizes from the files
	created by frame_sizes.

tools/compare_frame_sizes:
	A new script that compares the stack frame size information
	extracted from two different stage 2 directories by frame_sizes,
	reporting on both average stack frame sizes and on specific procedures
	that have different stack frame sizes in the two versions.
2002-03-28 03:44:41 +00:00
Fergus Henderson
7597790760 Use sub-modules to structure the modules in the Mercury compiler directory.
The main aim of this change is to make the overall, high-level structure
of the compiler clearer, and to encourage better encapsulation of the
major components.

compiler/libs.m:
compiler/backend_libs.m:
compiler/parse_tree.m:
compiler/hlds.m:
compiler/check_hlds.m:
compiler/transform_hlds.m:
compiler/bytecode_backend.m:
compiler/aditi_backend.m:
compiler/ml_backend.m:
compiler/ll_backend.m:
compiler/top_level.m:
	New files.  One module for each of the major components of the
	Mercury compiler.  These modules contain (as separate sub-modules)
	all the other modules in the Mercury compiler, except gcc.m and
	mlds_to_gcc.m.

Mmakefile:
compiler/Mmakefile:
	Handle the fact that the top-level module is now `top_level',
	not `mercury_compile' (since `mercury_compile' is a sub-module
	of `top_level').

compiler/Mmakefile:
	Update settings of *FLAGS-<modulename> to use the appropriate
	nested module names.

compiler/recompilation_check.m:
compiler/recompilation_version.m:
compiler/recompilation_usage.m:
compiler/recompilation.check.m:
compiler/recompilation.version.m:
compiler/recompilation.version.m:
	Convert the `recompilation_*' modules into sub-modules of the
	`recompilation' module.

compiler/*.m:
compiler/*.pp:
	Module-qualify the module names in `:- module', `:- import_module',
	and `:- use_module' declarations.

compiler/base_type_info.m:
compiler/base_type_layout.m:
	Deleted these unused empty modules.

compiler/prog_data.m:
compiler/globals.m:
	Move the `foreign_language' type from prog_data to globals.

compiler/mlds.m:
compiler/ml_util.m:
compiler/mlds_to_il.m:
	Import `globals', for `foreign_language'.

Mmake.common.in:
trace/Mmakefile:
runtime/Mmakefile:
	Rename the %.check.c targets as %.check_hdr.c,
	to avoid conflicts with compiler/recompilation.check.c.
2002-03-20 12:37:56 +00:00
Adrian Pellas-Rice
1c65d003f7 Add the shorthand_goal_expr wrapper type to ease hlds->hlds transformations.
Estimated hours taken: 4.5
Branches: main

Add the shorthand_goal_expr wrapper type to ease hlds->hlds transformations.

compiler/hlds_goal.m
        Create a new type, the `shorthand_goal_expr', for goals kinds that
        are implemented by a (ordinary_hlds + shorthand) -> (ordinary_hlds)
        transformation.  At present, bi_implication is the only kind of
        of goal that is implemented in this way.

        Moved bi_implication functor from the type goal_expr to the new
        shorthand_goal_expr type.

        Added the functor shorthand to the goal_expr type.

compiler/*.m
        Change switches on hlds_goal_expr that call error when they recognise
        `bi_implication' from calling error when they recognise
        `bi_implication' to calling error when they recognise `shorthand'.

        For all predicates K that
                a) switch on hlds_goal_expr and
                b) perform non-trivial processing when they recognise
                   `bi_implication'
        change K such that it now calls K_shorthand upon recognising the
        functor `shorthand'. Define K_shorthand to switch on
        shorthand_goal_expr, where the code for the `bi_implication' case
        formerly contained in K is now contained in K_shorthand.
2001-04-07 14:05:03 +00:00
Tyson Dowd
711da78188 Rename foreign_code as foreign_proc where appropriate in the compiler.
Estimated hours taken: 4.0
Branches: main

Rename foreign_code as foreign_proc where appropriate in the compiler.
The rationale for this change is that it makes maintaining the code much
simpler because it is clear whether `foreign' refers to a slab of code
(foreign_code) or a procedure (foreign_proc).

:- type pragma_foreign_code_attributes
:- type pragma_foreign_proc_attributes

The functors for pragma_type
	foreign(Lang, BodyCode)
	foreign(Attributes, Name, PredOrFunc, Vars, Varset, Impl)
become
	foreign_code(Lang, BodyCode)
	foreign_proc(Attributes, Name, PredOrFunc, Vars, Varset, Impl)

And the HLDS goal `pragma_foreign_code' becomes `foreign_proc'.

compiler/*.m:
	Update the compiler to use the new names.
2001-04-03 03:20:33 +00:00
Zoltan Somogyi
639dd4943c Put back the earlier clarification of cse_detection code, but without
Estimated hours taken: 16

compiler/cse_detection.m:
	Put back the earlier clarification of cse_detection code, but without
	the bug this time :-( The bug was that cse_detection did not insist
	on all branches of the branched control structure containing a copy
	of the "common" deconstruction unification. By hoisting that
	unification before the branched control structure, cse_detection
	was effectively adding a test into some computation paths.

	Fix common subexpression elimination so that it works when the
	deconstruction it hoists out of a branched control structure
	involves a functor with existentially typed arguments.

compiler/switch_detection.m:
	Modify the code called by cse_detection to look for deconstruction
	unifications to make it explicit whether the search was successful.

compiler/options.m:
	Put the default value of --compare-specialization back to 4, now
	that the bug that prevented it from working at levels above 1 (in the
	presence of existentially typed arguments) has been fixed.
2000-12-08 06:50:17 +00:00
Zoltan Somogyi
30a7319d32 Make the code for finding common subexpressions significantly clearer
Estimated hours taken: 4

compiler/cse_detection.m:
	Make the code for finding common subexpressions significantly clearer
	by using a single type for each possible state of the search, instead
	of dividing the state between a maybe and a bool.

	Instead of passing around several data structures separately,
	wrap them up in a cse_info data structure.

	Extend the cse_info data structure with fields that will be required
	to fix common subexpression elimination over existentially typed
	functors.

	Switch to using predmode declarations when appropriate.

compiler/switch_detection.m:
	Remove some redundancy from a comment.
2000-12-05 02:03:45 +00:00
Tyson Dowd
477ecb18f6 Implement pragma foreign_code for Managed C++.
Estimated hours taken: 60

Implement pragma foreign_code for Managed C++.

Currently you can only write MC++ code if your backend is capable of
generating use MC++ as its "native" foreign language.  The IL backend is
the only backend that does this at the moment (the other backends have C
as their "native" foreign language).

Most of the machinery is in place to call from C to (normal) C++
but there is little work done on actually spitting out the C++ code into
a separate file.  The IL backend does this step already with managed C++.
The intention is to turn foreign_code for C++ into a pragma import
(which imports the C++ function from a separate file) and
foreign_code for C (which calls the imported function).  The C++ code
will be inserted into a separate file that is compiled using C linkage.

The important improvement this change gives is that you can write a
module with a C and a MC++ implementations side-by-side.  The target
backend will select the most appropriate foreign language to use.
You can override its choice using --use-foreign-language.  Later on
we will probably want more flexibility than just a single language
selection option).

This change also implements :- pragma foreign_decl, which allows header
file style declarations to be written in languages other than C.

compiler/code_gen.m:
	Reject code that is not C when generating LLDS.

compiler/export.m:
	Start renaming C as foreign.
	Reject code that is not C when generating exports.

compiler/foreign.m:
	A new module to handle foreign language interfacing.
	The bulk of the code for pragma import has been moved here from
	make_hlds.

compiler/globals.m:
	Convert foreign language names to foreign_language.
	This code has been moved closer to the similar conversion we do
	for target language names.
	Add globals__io_lookup_foreign_language_option to make it easier
	to deterministically lookup the options relating to foreign
	languages.


compiler/hlds_module.m:
	Move module_add_foreign_decl and module_add_foreign_body_code
	from make_hlds.m (where they were called module_add_c_header and
	module_add_c_code).

compiler/hlds_out.m:
	Write the foreign language out in HLDS dumps.

compiler/llds.m:
	Change foreign_header_info to foreign_decl_info.
	Change definitions of foreign_decl_code and foreign_body_code to
	include the language.

compiler/llds_out.m:
	Reject code that is not C when writing out LLDS.

compiler/make_hlds.m:
	Add foreign language information to the bodys and decls when
	creating them.
	Update error messages to refer to foreign code instead of C
	code.
	Use foreign.m to generate interfaces from the backend language
	to the foreign language.
	Hardcode C as the language for fact tables.

compiler/mercury_compile.m:
	Collect the appropriate foreign language code together for
	output to the backend.

compiler/intermod.m:
compiler/mercury_to_mercury.m:
	Output the foreign language string.
	Change a few names to foreign_code instead of c_code.

compiler/ml_code_gen.m:
	Filter the foreign language bodys and decls so that we only get
	the ones we are in (given by the use-foreign-language option).

compiler/mlds_to_c.m:
	Abort if we are given non C foreign language code to output
	(we might handle it here in future, or we might handle it
	elsewhere).

compiler/mlds_to_ilasm.m:
	Abort if we are given non MC++ foreign language code to output
	(we might handle it here in future, or we might handle it
	elsewhere).

compiler/options.m:
compiler/handle_options.m:
	Add --use-foreign-language as a user option to control the
	preferred foreign language to use as the implementation of this
	module.
	Add backend_foreign_language as an internal option which stores
	the foreign language that the compiler will use as a default
	(e.g. the natural foreign language for the backend to use).
	Set the preferred backend foreign language depending on the
	target.

compiler/prog_data.m:
	Add managedcplusplus as a new alternative for the
	foreign_language type.
	Make c_header_code into foreign_decl.
	Give the foreign language for foreign_code as an attribute of
	the code.
	Write code to turn attributes into a list of strings (suitable
	for writing out by mercury_to_mercury).  This fixes what appears
	to be a bug in tabled_for_io -- the tabled_for_io attribute was not
	being written out.  Structure the code so this bug is
	difficult to repeat in future.

compiler/prog_io_pragma.m:
	Parse foreign_decl.
	Turn c_header_code into a special case of foreign_decl.

compiler/*.m:
	Remove the language field from pragma_foreign_code, it is now an
	attribute of the code.
	Various type and variable renamings.

tests/invalid/pragma_c_code_and_clauses1.err_exp:
tests/invalid/pragma_c_code_dup_var.err_exp:
tests/warnings/singleton_test.exp:
	Update the tests to reflect the new error messages talking
	about :- pragma foreign_code rather than :- pragma c_code.
2000-11-17 17:48:52 +00:00
Peter Ross
35d1d914e7 Update the MLDS backend to handle structure reuse and compile time gc.
Estimated hours taken: 20

Update the MLDS backend to handle structure reuse and compile time gc.
Note that currently no pass on the main branch currently generates this
information yet.

mlds.m:
    Add a new instruction delete_object which is to be inserted
    whenever a lval can be compile time garbage collected.

ml_unify_gen.m:
    Handle the case where the HowToConstruct field of a construction
    is reuse_cell(_).
    Handle the case where a deconstruction can be compile time gc'd.

hlds_goal.m:
    Add a new field, can_cgc, to deconstruction unifications.  This
    field is `yes' if the deconstruction unification can be compile time
    garbage collected.

hlds_out.m:
    Output the can_cgc field.  Output unification information if we
    request the structure reuse information.

ml_elim_nested.m:
mlds_to_c.m:
    Handle the delete_object instruction.

builtin_ops.m:
    Fix a bug where body was an unary op instead of a binary op.

bytecode.m:
c_util.m:
llds.m:
opt_debug.m:
vn_cost.m:
    Changes to reflect that body is a binary op.

bytecode_gen.m:
code_aux.m:
common.m:
cse_detection.m:
dependency_graph.m:
det_analysis.m:
goal_util.m:
higher_order.m:
mark_static_terms.m:
mode_util.m:
modecheck_unify.m:
pd_cost.m:
pd_util.m:
prog_rep.m:
rl_exprn.m:
rl_key.m:
simplify.m:
switch_detection.m:
term_traversal.m:
unify_gen.m:
unused_args.m:
    Handle the can compile time gc field in deconstruction unifications.
2000-10-06 10:18:39 +00:00
Tyson Dowd
c192d50143 Add preliminary support for a new pragma:
Estimated hours taken: 15

Add preliminary support for a new pragma:

:- pragma foreign_code(LanguageString, .... <same args as c_code>).

This is intended to be the eventual replacement of pragma c_code.
Presently the only valid language is "C".
The existing pragma c_code is simply turned into pragma foreign_code.

pragma foreign_code is not a supported pragma at the moment.  There are
several other changes that are intended (for example, foreign_code will
be impure by default).

This change also changes the HLDS goal pragma_c_code/7 to
pragma_foreign_code/8 where the extra argument is the foreign language.

Any code currently generating output for pragma C code simply checks
that the foreign language is set to "c".  Since this is the only
alternative of the type foreign_language, it will always succeed.
However when new alternatives are added it should be fairly easy to find
where the changes need to be made.

Some type names and predicate names have also been updated, however
there are many more that haven't yet been touched.

compiler/prog_io_pragma.m:
	Accept the new syntax.	Turn the old syntax into the new item.

compiler/hlds_goal.m:
	Change pragma_c_code/7 to pragma_foreign_code/8.
	Define the foreign_language type.

compiler/llds.m:
	Change user_c_code/2 to user_foreign_code/3.

compiler/*.m:
	Update the rest of the compiler to handle these types.
	Make a few small changes to update variable names, predicate
	names and type names.
2000-08-09 07:48:04 +00:00
Zoltan Somogyi
9dcab9bee2 Add a new optimization, enabled by the option --unneeded-code.
Estimated hours taken: 40

Add a new optimization, enabled by the option --unneeded-code. This
optimization removes goals whose outputs are not used at all, and moves goals
whose outputs are only used on some computation branches to the starts of
those branches, so they do not need to be executed on other branches.

Such deletions/movements are done only when the semantic switches and the
properties of the relevant goal together permit it.

compiler/unneeded_code.m:
	A new module to perform the goal rearrangement.

compiler/hlds_goal.m:
	The new optimization needs to know how many functors the switched-on
	variable can be bound to, so it can check whether a given number of
	switch arms covers all alternatives or not. To make access to this
	information convenient, we add a field to the goal_path_step
	alternative for switch arm entry that records this number.

compiler/goal_path.m:
	Fill in this number.

	To make this possible, we thread the necessary information through the
	predicates in this module.

compiler/type_util.m:
	Add a utility predicate type_util__switch_type_num_functors, for use
	by the new code in goal_path.m.

compiler/switch_detection.m:
	Avoid duplicated code by using type_util__switch_type_num_functors
	where relevant.

compiler/code_aux.m:
	Add three new auxiliary predicate, code_aux__goal_cannot_loop_or_throw,
	code_aux__goal_can_loop_or_throw and code_aux__goal_can_loop, to the
	existing code_aux__goal_cannot_loop. code_aux__goal_cannot_loop
	now checks only what its name says.

compiler/trace.m:
	Ignore the new field when generating goal paths strings.

compiler/mercury_compile.m:
	Invoke unneeded_code.m if required.

compiler/hlds_pred.m:
	Add some utility predicates for use by unneeded_code.m.

compiler/unused_args.m:
	Use the new utility predicates instead of reimplementing them.

compiler/options.m:
	Define the --unneeded-code option, and its auxiliary,
	--unneeded-code-copy-limit.

doc/user_guide.texi:
	Document the new options.
2000-07-25 09:27:38 +00:00
Fergus Henderson
d551dd1dc9 Handle quantification analysis of bi-implication (`<=>') goals correctly.
Estimated hours taken: 10

Handle quantification analysis of bi-implication (`<=>') goals correctly.
Previously we used to expand bi-implications before doing quantification
analysis, which stuffed up the results of quantification analysis for
those goals.  We need to do quantification analysis first, and only
then can we expand bi-implications.  In addition, elimination of double
negation needs to come after expansion of bi-implication, so I moved
that from make_hlds.m to purity.m.

compiler/hlds_goal.m:
	Add a new alternative to the HLDS goal type for bi-implications.
        Also add a new predicate negate_goal, for use by purity.m.

compiler/make_hlds.m:
	Don't expand bi-implication here, instead just use the new
	bi_implication/2 HLDS goal type.
	Don't eliminated double negation here.

compiler/quantification.m:
	Handle quantification for bi-implications.
	Expand bi-implications.

compiler/purity.m:
	Eliminate double negation.

compiler/hlds_out.m:
	Add code to print out bi-implication goals.

compiler/*.m:
	Trivial changes to handle the new bi_implication/2
	alternative in the HLDS goal type.

compiler/notes/compiler_design.html:
	Document the above changes.

tests/hard_coded/Mmakefile:
tests/hard_coded/quantifier2.m:
tests/hard_coded/quantifier2.exp:
	A regression test for the above change.
1999-10-25 03:53:14 +00:00
Simon Taylor
8bb9f777ac Fix a bug - the code was looking for switch deconstructions
Estimated hours taken: 1

compiler/switch_detection.m:
	Fix a bug - the code was looking for switch deconstructions
	after the first call in each branch. Doing this can remove
	infinite loops, which the strict sequential semantics does
	not allow.

NEWS:
	Discuss the backwards incompatibility effects of this change.

doc/reference_manual.texi:
	Add some more documentation about where the test unifications
	in switches can occur.

tests/invalid/Mmakefile:
tests/invalid/not_a_switch.m:
	Test case.
1999-08-31 04:16:33 +00:00
Simon Taylor
2725b1a331 Aditi update syntax, type and mode checking.
Estimated hours taken: 220

Aditi update syntax, type and mode checking.

Change the hlds_goal for constructions in preparation for
structure reuse to avoid making multiple conflicting changes.

compiler/hlds_goal.m:
	Merge `higher_order_call' and `class_method_call' into a single
	`generic_call' goal type. This also has alternatives for the
	various Aditi builtins for which type declarations can't
	be written.

	Remove the argument types field from higher-order/class method calls.
	It wasn't used often, and wasn't updated by optimizations
	such as inlining. The types can be obtained from the vartypes
	field of the proc_info.

	Add a `lambda_eval_method' field to lambda_goals.

	Add a field to constructions to identify which RL code fragment should
	be used for an top-down Aditi closure.

	Add fields to constructions to hold structure reuse information.
	This is currently ignored -- the changes to implement structure
	reuse will be committed to the alias branch.
	This is included here to avoid lots of CVS conflicts caused by
	changing the definition of `hlds_goal' twice.

	Add a field to `some' goals to specify whether the quantification
	can be removed. This is used to make it easier to ensure that
	indexes are used for updates.

	Add a field to lambda_goals to describe whether the modes were
	guessed by the compiler and may need fixing up after typechecking
	works out the argument types.

	Add predicate `hlds_goal__generic_call_id' to work out a call_id
	for a generic call for use in error messages.

compiler/purity.m:
compiler/post_typecheck.m:
	Fill in the modes of Aditi builtin calls and closure constructions.
	This needs to know which are the `aditi__state' arguments, so
	it must be done after typechecking.

compiler/prog_data.m:
	Added `:- type sym_name_and_arity ---> sym_name/arity'.

	Add a type `lambda_eval_method', which describes how a closure
	is to be executed. The alternatives are normal Mercury execution,
	bottom-up execution by Aditi and top-down execution by Aditi.

compiler/prog_out.m:
	Add predicate `prog_out__write_sym_name_and_arity', which
	replaces duplicated inline code in a few places.

compiler/hlds_data.m:
	Add a `lambda_eval_method' field to `pred_const' cons_ids and
	`pred_closure_tag' cons_tags.

compiler/hlds_pred.m:
	Remove type `pred_call_id', replace it with type `simple_call_id',
	which combines a `pred_or_func' and a `sym_name_and_arity'.

	Add a type `call_id' which describes all the different types of call,
	including normal calls, higher-order and class-method calls
	and Aditi builtins.

	Add `aditi_top_down' to the type `marker'.

	Remove `aditi_interface' from type `marker'. Interfacing to
	Aditi predicates is now handled by `generic_call' hlds_goals.

	Add a type `rl_exprn_id' which identifies a predicate to
	be executed top-down by Aditi.
	Add a `maybe(rl_exprn_id)'  field to type `proc_info'.

	Add predicate `adjust_func_arity' to convert between the arity
	of a function to its arity as a predicate.

	Add predicates `get_state_args' and `get_state_args_det' to
	extract the DCG state arguments from an argument list.

	Add predicate `pred_info_get_call_id' to get a `simple_call_id'
	for a predicate for use in error messages.

compiler/hlds_out.m:
	Write the new representation for call_ids.

	Add a predicate `hlds_out__write_call_arg_id' which
	replaces similar code in mode_errors.m and typecheck.m.

compiler/prog_io_goal.m:
	Add support for `aditi_bottom_up' and `aditi_top_down' annotations
	on pred expressions.

compiler/prog_io_util.m:
compiler/prog_io_pragma.m:
	Add predicates
	- `prog_io_util:parse_name_and_arity' to parse `SymName/Arity'
		(moved from prog_io_pragma.m).
	- `prog_io_util:parse_pred_or_func_name_and_arity to parse
		`pred SymName/Arity' or `func SymName/Arity'.
	- `prog_io_util:parse_pred_or_func_and_args' to parse terms resembling
		a clause head (moved from prog_io_pragma.m).

compiler/type_util.m:
	Add support for `aditi_bottom_up' and `aditi_top_down' annotations
	on higher-order types.

	Add predicates `construct_higher_order_type',
	`construct_higher_order_pred_type' and
	`construct_higher_order_func_type' to avoid some code duplication.

compiler/mode_util.m:
	Add predicate `unused_mode/1', which returns `builtin:unused'.
	Add functions `aditi_di_mode/0', `aditi_ui_mode/0' and
	`aditi_uo_mode/0' which return `in', `in', and `out', but will
	be changed to return `di', `ui' and `uo' when alias tracking
	is implemented.

compiler/goal_util.m:
	Add predicate `goal_util__generic_call_vars' which returns
	any arguments to a generic_call which are not in the argument list,
	for example the closure passed to a higher-order call or
	the typeclass_info for a class method call.

compiler/llds.m:
compiler/exprn_aux.m:
compiler/dupelim.m:
compiler/llds_out.m:
compiler/opt_debug.m:
	Add builtin labels for the Aditi update operations.

compiler/hlds_module.m:
	Add predicate predicate_table_search_pf_sym, used for finding
	possible matches for a call with the wrong number of arguments.

compiler/intermod.m:
	Don't write predicates which build `aditi_top_down' goals,
	because there is currently no way to tell importing modules
	which RL code fragment to use.

compiler/simplify.m:
	Obey the `cannot_remove' field of explicit quantification goals.

compiler/make_hlds.m:
	Parse Aditi updates.

	Don't typecheck clauses for which syntax errors in Aditi updates
	are found - this avoids spurious "undefined predicate `aditi_insert/3'"
	errors.

	Factor out some common code to handle terms of the form `Head :- Body'.
	Factor out common code in the handling of pred and func expressions.

compiler/typecheck.m:
	Typecheck Aditi builtins.

	Allow the argument types of matching predicates to be adjusted
	when typechecking the higher-order arguments of Aditi builtins.

	Change `typecheck__resolve_pred_overloading' to take a list of
	argument types rather than a `map(var, type)' and a list of
	arguments to allow a transformation to be performed on the
	argument types before passing them.

compiler/error_util.m:
	Move the part of `report_error_num_args' which writes
	"wrong number of arguments (<x>; expected <y>)" from
	typecheck.m for use by make_hlds.m when reporting errors
	for Aditi builtins.

compiler/modes.m:
compiler/unique_modes.m:
compiler/modecheck_call.m:
	Modecheck Aditi builtins.

compiler/lambda.m:
	Handle the markers for predicates introduced for
	`aditi_top_down' and `aditi_bottom_up' lambda expressions.

compiler/polymorphism.m:
	Add extra type_infos to `aditi_insert' calls
	describing the tuple to insert.

compiler/call_gen.m:
	Generate code for Aditi builtins.

compiler/unify_gen.m:
compiler/bytecode_gen.m:
	Abort on `aditi_top_down' and `aditi_bottom_up' lambda
	expressions - code generation for them is not yet implemented.

compiler/magic.m:
	Use the `aditi_call' generic_call rather than create
	a new procedure for each Aditi predicate called from C.

compiler/rl_out.pp:
compiler/rl_gen.m:
compiler/rl.m:
	Move some utility code used by magic.m and call_gen.m into rl.m.

	Remove an XXX comment about reference counting being not yet
	implemented - Evan has fixed that.

library/ops.m:
compiler/mercury_to_mercury.m:
doc/transition_guide.texi:
	Add unary prefix operators `aditi_bottom_up' and `aditi_top_down',
	used as qualifiers on lambda expressions.
	Add infix operator `==>' to separate the tuples in an
	`aditi_modify' call.

compiler/follow_vars.m:
	Thread a `map(prog_var, type)' through, needed because
	type information is no longer held in higher-order call goals.

compiler/table_gen.m:
	Use the `make_*_construction' predicates in hlds_goal.m
	to construct constants.

compiler/*.m:
	Trivial changes to add extra fields to hlds_goal structures.

doc/reference_manual.texi:
	Document Aditi updates.

	Use @samp{pragma base_relation} instead of
	@samp{:- pragma base_relation} throughout the Aditi documentation
	to be consistent with other parts of the reference manual.

tests/valid/Mmakefile:
tests/valid/aditi_update.m:
tests/valid/aditi.m:
	Test case.

tests/valid/Mmakefile:
	Remove some hard-coded --intermodule-optimization rules which are
	no longer needed because `mmake depend' is now run in this directory.

tests/invalid/*.err_exp:
	Fix expected output for changes in reporting of call_ids
	in typecheck.m.

tests/invalid/Mmakefile
tests/invalid/aditi_update_errors.{m,err_exp}:
tests/invalid/aditi_update_mode_errors.{m,err_exp}:
	Test error messages for Aditi updates.

tests/valid/aditi.m:
tests/invalid/aditi.m:
	Cut down version of extras/aditi/aditi.m to provide basic declarations
	for Aditi compilation such as `aditi__state' and the modes
	`aditi_di', `aditi_uo' and `aditi_ui'. Installing extras/aditi/aditi.m
	somewhere would remove the need for these.
1999-07-13 08:55:28 +00:00
Thomas Conway
5c955626f2 These changes make var' and term' polymorphic.
Estimated hours taken: 20

These changes make `var' and `term' polymorphic. This allows us to make
variables and terms representing types of a different type to those
representing program terms and those representing insts.

These changes do not *fix* any existing problems (for instance
there was a messy conflation of program variables and inst variables,
and where necessary I've just called varset__init(InstVarSet) with
an XXX comment).

NEWS:
	Mention the changes to the standard library.

library/term.m:
	Make term, var and var_supply polymorphic.
	Add new predicates:
		term__generic_term/1
		term__coerce/2
		term__coerce_var/2
		term__coerce_var_supply/2

library/varset.m:
	Make varset polymorphic.
	Add the new predicate:
		varset__coerce/2

compiler/prog_data.m:
	Introduce type equivalences for the different kinds of
	vars, terms, and varsets that we use (tvar and tvarset
	were already there but have been changed to use the
	polymorphic var and term).

	Also change the various kinds of items to use the appropriate
	kinds of var/varset.

compiler/*.m:
	Thousands of boring changes to make the compiler type correct
	with the different types for type, program and inst vars and
	varsets.
1998-11-20 04:10:36 +00:00
Simon Taylor
2727699e93 Fix a bug where cse_detection failed to hoist a common deconstruction for
Estimated hours taken: 5

Fix a bug where cse_detection failed to hoist a common deconstruction for
a one-armed switch out where switch_detection expected it to, due to a
call getting in the way. This resulted in switch_detection not finding
a switch necessary to prove determinism correctness.

compiler/switch_detection.m:
compiler/cse_detection.m:
	Make both modules use the same code to find deconstructions of
	non-local variables of disjunctions.

tests/valid/switch_detection_bug2.m:
	Test case, taken from samples/diff.
1998-09-10 06:18:48 +00:00
Thomas Conway
a70b59e83c Add a test to find the number of words needed to represent a
configure.in:
        Add a test to find the number of words needed to represent a
        synchronization term.

boehm_gc/gc.h:
        fix a declaration by replacing the args () with (void).
boehm_gc/solaris_pthreads.c:
        add a missing include
        check the return values of pthread calls.

compiler/*.m:
        Add handling for the new HLDS goal type par_conj.
        Add handling for the four new LLDS instructions:
                init_sync_term
                fork
                join_and_terminate
                join_and_continue

compiler/code_info.m:
        add a new alternative for slot_contents - sync_term.

compiler/handle_options.m:
        add .par as part of the grade

compiler/hlds_goal.m:
        add the new goal type par_conj.

compiler/instmap.m:
        add instmap__unify which takes a list of instmaps
                and abstractly unifies them.
        add unify_instmap_delta which tajes two instmap deltas
                and abstractly unifies them.

compiler/llds.m:
        add the new llds instructions.

compiler/mode_info.m:
        add par_conj as a lock reason.

library/Makefile:
        work around a bug in the solaris version pthread.h

library/benchmarking.m:
        reference the stack zones from the engine structure
        rather than from global variables.

library/{nc,sp}_builtin.nl:
        add an op declaration for &.

library/std_util.m:
        change references to global variables to references inside
        the engine structure.

runtime/Mmakefile:
        add mercury_thread.{c,h}
        add THREADLIBS to the libraries

runtime/*.{c,h}
        Remove some old junk from the previous processes/shrd-mem
        changes that found their way into the repository.
        Add MR_ prefixes to lots of names.

runtime/mercury_context.c:
        Add init_thread_stuff for creating and initializing a
        context structure for the current thread.

runtime/mercury_context.h:
        add a field to the mercury context which stores the thread id
        of the thread where this context originated.
        add various macros for implementing the new llds instructions.

runtime/mercury_engine.c:
        initialize the engine structure, rather than a bunch of globals.

runtime/mercury_engine.h:
        declare the mercury_engine structure.

runtime/mercury_regorder.h:
        if MR_THREAD_SAFE, and there is at least one global register
        then use mr0 as a pointer to the mercury engine structure.

scripts/init_grade_options.sh-subr
        add thread_safe

scripts/mgnuc.in
        add THREAD_OPTS

scripts/ml.in:
        add THREAD_LIBS
1998-06-09 02:16:31 +00:00
Oliver Hutchison
bcf7dbf9f8 Add support for tabling.
Estimated hours taken: 250

Add support for tabling.

This change allows for model_det, model_semidet and model_non memoing,
minimal model and loop detection tabling.

compiler/base_type_layout.m:
	Update comments to reflect new runtime naming standard.

compiler/det_analysis.m:
	Allow tabling to change the result of det analysis. This is
	necessary in the case of minimal model tabling which can
	turn a det procedure into a semidet one.

compiler/det_report.m:
compiler/hlds_data.m:
	Add code to report error messages for various non compatible
	tabling methods and determinism.

compiler/hlds_out.m:
compiler/modules.m:
	Remove reference to the old memo marker.

compiler/hlds_pred.m:
	Create new type (eval_method) to define which of the available
	evaluation methods should be used each procedure.
	Add new field to the proc_info structure.
	Add several new predicates relating to the new eval_method type.

compiler/inlining.m:
compiler/intermod.m:
	Make sure only procedures with normal evaluation are inlined.

compiler/make_hlds.m:
	Add code to process new tabling pragmas.

compiler/mercury_compile.m:
	Call the tabling transformation code.

compiler/modes.m:
	Make sure that all procedures with non normal evaluation have
	no unique/partially instantiated modes. Produce error messages
	if they do. Support for partially instantiated modes is currently
	missing as it represents a large amount of work for a case that
	is currently not used.

compiler/module_qual.m:
compile/prog_data.m:
compiler/prog_io_pragma.m:
	Add three new pragma types:
		`memo'
		`loop_check'
		`minimal_model'
	and code to support them.

compiler/simplify.m:
	Don't report infinite recursion warning if a procedure has
	minimal model evaluation.

compiler/stratify.m:
	Change the stratification analyser so that it reports cases of
	definite non-stratification. Rather than reporting warnings for
	any code that is not definitely stratified.
	Remove reference to the old memo marker.

compiler/switch_detection.m:
	Fix a small bug where goal were being placed in reverse order.
	Call list__reverse on the list of goals.

compiler/table_gen.m:
	New module to do the actual tabling transformation.

compiler/notes/compiler_design.html:
	Document addition of new tabling pass to the compiler.

doc/reference_manual.texi:
	Fix mistake in example.

library/mercury_builtin.m:
	Add many new predicates for support of tabling.

library/std_util.m:
library/store.m:
	Move the functions :
		ML_compare_type_info
		ML_collapse_equivalences
		ML_create_type_info
	to the runtime.

runtime/mercury_deep_copy.c:
runtime/mercury_type_info.h:
runtime/mercury_type_info.c:
	Move the make_type_info function into the mercury_type_info module
	and make it public.

runtime/Mmakefile:
runtime/mercury_imp.h:
	Add references to new files added for tabling support.

runtime/mercury_string.h:
	Change hash macro so it does not cause a name clash with any
	variable called "hash".

runtime/mercury_type_info.c:
runtime/mercury_type_info.h:
	Add three new functions taken from the library :
		MR_compare_type_info
		MR_collapse_equivalences
		MR_create_type_info.

runtime/mercury_table_any.c:
runtime/mercury_table_any.h:
runtime/mercury_table_enum.c:
runtime/mercury_table_enum.h:
runtime/mercury_table_int_float_string.c:
runtime/mercury_table_int_float_string.h:
runtime/mercury_table_type_info.c:
runtime/mercury_table_type_info.h:
runtime/mercury_tabling.h:
	New modules for the support of tabling.
1998-05-15 07:09:29 +00:00
Fergus Henderson
49c25842cf Fix a problem reported by Baudouin Le Charlier <ble@info.fundp.ac.be>
where switch detection was getting confused by explicit existential
quantifications.

compiler/switch_detection.m:
	When detecting switches, traverse through some/2 goals.
	Also simplify the code a bit.

tests/valid/Mmakefile:
tests/valid/some_switch.m:
	Regression test for the above change.
1998-05-12 17:05:04 +00:00
Simon Taylor
d0085d8119 Assorted changes to make the HLDS type and mode correct
Estimated hours taken: 45

Assorted changes to make the HLDS type and mode correct
after lambda expansion. The HLDS is still not unique mode
correct after common structure elimination.

compiler/det_analysis.m
	Make sure the inferred_determinism field of the proc_info is filled
	in correctly for imported procedures and class methods.

compiler/mode_util.m
	Fix a bug in recompute_instmap_delta_call to do with unreachable
	instmaps. This caused an abort a couple of months ago when
	compiling with --deforestation (not yet committed), but
	can't currently be reproduced.

compiler/hlds_pred.m
compiler/lambda.m
	Add a field to the proc_info to record which args_method
	should be used for this procedure. Procedures directly
	called by do_call_*_closure must be compiled with
	the `compact' argument convention to avoid the need to permute
	the arguments so inputs come before outputs.

compiler/lambda.m
compiler/higher_order.m
	Remove permutation of argument variables of lambda expressions
	so the HLDS is type and mode correct and mode analysis can
	be rerun. Otherwise, rerunning mode analysis will fail on
	tests/hard_coded/ho_order.m.

compiler/arg_info.m
	Added arg_info__ho_call_args_method which returns
	an args_method which can always be directly called by
	do_call_*_closure (`compact').
	Added arg_info__args_method_is_ho_callable to check that
	a given args_method can be directly called.

compiler/unify_gen.m
	Abort if a closure is created for a procedure compiled
	with the simple argument convention.

compiler/hlds_goal.m
compiler/lambda.m
	Mode analysis was not storing the non-locals list on which the
	uni_modes field of the construction of a lambda goal was computed.
	If the nonlocals were renamed, the sort order could change, and
	the non-locals could be incorrectly matched with the arguments
	of the introduced lambda expression, causing a mode error. The
	argument list is now stored.
	This caused rerunning mode-checking on tests/valid/lazy_list.m
	after polymorphism to fail.

compiler/*.m
	Fill in the args_method field of proc_infos with the value
	from the globals.
	Handle the extra argument to the lambda_goal unify_rhs.

compiler/follow_vars.m
	Remove code to handle complicated unifications, since
	they should be removed by polymorphism.m.

compiler/special_pred.m
library/mercury_builtin.m
	Make the uniqueness of the comparison_result argument
	of builtin_compare_* and the automatically generated
	comparison procedures match that of compare/3. Unique mode
	errors will still be introduced if polymorphism.m specializes
	calls to any of the unique modes of compare/3 and then mode analysis
	is rerun, since the compiler-generated comparison procedures
	only implement the (uo, in, in) mode. (This is not yet a problem
	because currently we don't rerun mode analysis.)

runtime/mercury_ho_call.c
	Remove code in do_call_*_closure to deal with the
	`simple' args_method. Since the output arguments no longer
	need to be moved, the closure call is now a tailcall.
	Remove some magic numbers.

compiler/modecheck_unify.m
	Avoid some aborts and mode errors when rerunning mode analysis,
	especially those resulting from not_reached insts being treated
	as bound.
	Avoid aborting on higher-order predicate constants with multiple
	modes if lambda expansion has already been run.

tests/valid/higher_order.m
        Add a test case for an abort in mode analysis when
	compiling with --deforestation (not yet committed),
	due to a predicate constant for a procedure with multiple
	modes.

tests/valid/unreachable_code.m
	Add a test case for bogus higher-order unification
	mode errors in unreachable code.
1998-02-12 01:17:56 +00:00
Zoltan Somogyi
5013dd9c76 Implement nondet pragma C codes.
Estimated hours taken: 40

Implement nondet pragma C codes.

runtime/mercury_stacks.h:
	Define a new macro, mkpragmaframe, for use in the implementation
	of nondet pragma C codes. This new macro includes space for a
	struct with a given sruct tag in the nondet stack frame being created.

compiler/{prog_data.m,hlds_goal.m}:
	Revise the representation of pragma C codes, both as the item and
	in the HLDS.

compiler/prog_io_pragma.m:
	Parse nondet pragma C declarations.

	Fix the indentation in some places.

compiler/llds.m:
	Include an extra argument in mkframe instructions. This extra argument
	gives the details of the C structure (if any) to be included in the
	nondet stack frame to be created.

	Generalize the LLDS representation of pragma C codes. Instead of a
	fixed sequence of <assign from inputs, user c code, assign to outputs>,
	let the sequence contain these elements, as well as arbitrary
	compiler-generated C code, in any order and possibly with repetitions.
	This flexibility is needed for nondet pragma C codes.

	Add a field to pragma C codes to say whether they can call Mercury.
	Some optimizations can do a better job if they know that a pragma C
	code cannot call Mercury.

	Add another field to pragma C codes to give the name of the label
	they refer to (if any). This is needed to prevent labelopt from
	incorrectly optimizing away the label definition.

	Add a new alternative to the type pragma_c_decl, to describe the
	declaration of the local variable that points to the save struct.

compiler/llds_out.m:
	Output mkframe instructions that specify a struct as invoking the new
	mkpragmaframe macro, and make sure that the struct is declared just
	before the procedure that uses it.

	Other minor changes to keep up with the changes to the representation
	of pragma C code in the LLDS, and to make the output look a bit nicer.

compiler/pragma_c_gen.m:
	Add code to generate code for nondet pragma C codes. Revise the utility
	predicates and their data structures a bit to make this possible.

compiler/code_gen.m:
	Add code for the necessary special handling of prologs and epilogs
	of procedures defined by nondet pragma C codes. The prologs need
	to be modified to include a programmer-defined C structure in the
	nondet stack frame and to communicate the location of this structure
	to the pragma C code, whereas the functionality of the epilog is
	taken care of by the pragma C code itself.

compiler/make_hlds.m:
	When creating a proc_info for a procedure defined by a pragma C code,
	we used to insert unifications between the headvars and the vars of
	the pragma C code into the body goal. We now perform substitutions
	instead. This removes a factor that would complicate the generation
	of code for nondet pragma C codes.

	Pass a moduleinfo down the procedures that warn about singletons
	(and other basic scope errors). When checking whether to warn about
	an argument of a pragma C code not being mentioned in the C code
	fragment, we need to know whether the argument is input or output,
	since input variables should appear in some code fragments in a
	nondet pragma C code and must not appear in others. The
	mode_is_{in,out}put checks need the moduleinfo.

	(We do not need to check for any variables being mentioned where
	they shouldn't be. The C compiler will fail in the presence of any
	errors of that type, and since those variables could be referred
	to via macros whose definitions we do not see, we couldn't implement
	a reliable test anyway.)

compiler/opt_util.m:
	Recognize that some sorts of pragma_c codes cannot affect the data
	structures that control backtracking. This allows peepholing to
	do a better job on code sequences produced for nondet pragma C codes.

	Recognize that the C code strings inside some pragma_c codes refer to
	other labels in the procedure. This prevents labelopt from incorrectly
	optimizing away these labels.

compiler/dupelim.m:
	If a label is referred to from within a C code string, then do not
	attempt to optimize it away.

compiler/det_analysis.m:
	Remove a now incorrect part of an error message.

compiler/*.m:
	Minor changes to conform to changes to the HLDS and LLDS data
	structures.
1998-01-13 10:14:23 +00:00
Zoltan Somogyi
bb4442ddc1 Update copyright dates for 1998.
Estimated hours taken: 0.5

compiler/*.m:
	Update copyright dates for 1998.
1998-01-13 10:06:08 +00:00
David Jeffery
7406335105 This change implements typeclasses. Included are the necessary changes to
Estimated hours taken: 500 or so

This change implements typeclasses. Included are the necessary changes to
the compiler, runtime and library.

compiler/typecheck.m:
	Typecheck the constraints on a pred by adding constraints for each
	call to a pred/func with constraints, and eliminating constraints
	by applying context reduction.

	While reducing the constraints, keep track of the proofs so that
	polymorphism can produce the tyepclass_infos for eliminated
	constraints.

compiler/polymorphism.m:
	Perform the source-to-source transformation which turns code with
	typeclass constraints into code without constraints, but with extra
	"typeclass_info", or "dictionary" parameters.

	Also, rather than always having a type_info directly for each type
	variable, sometimes the type_info is hidden inside a typeclass_info.

compiler/bytecode*.m:
	Insert some code to abort if bytecode generation is used when
	typeclasses are used.
compiler/call_gen.m:
	Generate code for a class_method_call, which forms the body of a class
	method (by selecting the appropriate proc from the typeclass_info).
compiler/dead_proc_elim.m:
	Don't eliminate class methods if they are potentially used outside
	the module
compiler/hlds_data.m:
	Define data types to store:
		- the typeclass definitions
		- the instances of a class
		- "constraint_proof". ie. the proofs of redundancy of a
		  constraint. This info is used by polymorphism to construct the
		  typeclass_infos for a constraint.
		- the "base_tyepclass_info_constant", which is analagous the
		  the base_type_info_constant
compiler/hlds_data.m:
	Define the class_method_call goal. This goal is inserted into the
	body of class method procs, and is responsible for selecting the
	appropriate part of the typeclass_info to call.
compiler/hlds_data.m:
	Add the class table and instance table to the module_info.
compiler/hlds_out.m:
	Output info about base_typeclass_infos and class_method_calls
compiler/hlds_pred.m:
	Change the representation of the locations of type_infos from "var"
	to type_info_locn, which is either a var, or part of a typeclass_info,
	since now the typeclass_infos contain the type_infos for the type that
	they constrain.

	Add constraints to the pred_info.

	Add constraint_proofs to the pred_info (so that typeclass.m can
	annotate the pred_info with the reasons that constraints were
	eliminated, so that polymorphism.m can in turn generate the
	typeclass_infos for the constraints).

	Add the "class_method" marker.

compiler/lambda.m:
	A feable attempt at adding class ontexts to lambda expressions,
	untested and almost certainly not working.
compiler/llds_out.m:
	Output the code addresses for do_*det_class_method, and output
	appropriately mangled symbol names for base_typeclass_infos.
compiler/make_hlds.m:
	Add constraints to the types on pred and func decls, and add
	class and instance declarations to the class_table and instance_table
	respectively.
compiler/mercury_compile.m:
	Add the check_typeclass pass.
compiler/mercury_to_mercury.m:
	Output constraints of pred and funcs, and output typeclass and instance
	declarations.
compiler/module_qual.m:
	Module qualify typeclass names in pred class contexts, and qualify the
	typeclass and instance decls themselves.
compiler/modules.m:
	Output typeclass declarations in the short interface too.
compiler/prog_data.m:
	Add the "typeclass" and "instance" items. Define the types to store
	information about the declarations, including class contexts on pred
	and func decls.
compiler/prog_io.m:
	Parse constraints on pred and func declarations.
compiler/prod_out.m:
	Output class contexts on pred and func decls.
compiler/type_util.m:
	Add preds to apply a substitution to a class_constraint, and to
	a list of class constraints. Add type_list_matches_exactly/2. Also
	add typeclass_info and base_typeclass_info as types which should not
	be optimised as no_tag types (seeing that we cheat a bit about their
	representation).
compiler/notes/compiler_design.html:
	Add notes on module qualification of class contexts. Needs expansion
	to include more stuff on typeclasses.
compiler/*.m:
	Various minor changes.

New Files:
compiler/base_typeclass_info.m:
	Produce one base_typeclass_info for each instance declaration.
compiler/prog_io_typeclass.m:
	Parse typeclass and instance declarations.
compiler/check_typeclass.m:
	Check the conformance of an instance declaration to the typeclass
	declaration, including building up a proof of how superclass
	constraints are satisfied so that polymorphism.m is able to construct
	the typeclass_info, including the superclass typeclass_infos.

library/mercury_builtin.m:
	Implement that base_typeclass_info and typeclass_info types, as
	well as the predicates type_info_from_typeclass_info/3 to extract
	a type_info from a typeclass_info, and superclass_from_typeclass_info/3
	for extracting superclasses.
library/ops.m:
	Add "typeclass" and "instance" as operators.
library/string.m:
	Add a (in, uo) mode for string__length/3.

runtime/mercury_ho_call.c:
	Implement do_call_*det_class_method, which are the pieces of code
	responsible for extracting the correct code address from the
	typeclass_info, setting up the arguments correctly, then executing
	the code.
runtime/mercury_type_info.h:
	Macros for accessing the typeclass_info structure.
1997-12-19 03:10:47 +00:00
Fergus Henderson
5976f769f7 Fix a bug for the case of a higher-order function call in code
Estimated hours taken: 1

Fix a bug for the case of a higher-order function call in code
with common sub-expression; mercury 0.7 failed this test, reporting
"Software Error: modecheck fails when repeated", due to confusion
between h.o. _function_ call and h.o. _predicate_ call.

compiler/hlds_goal.m:
	Add `pred_or_func' field to HLDS higher_order_calls.

compiler/modes.m:
compiler/modecheck_call.m:
compiler/hlds_out.m:
compiler/*.m:
	Add code to handle new field for higher_order_call goals.

tests/valid/Mmake:
tests/valid/ho_func_call.m:
	Regression test for the above-mentioned bug.
1997-09-01 14:05:44 +00:00
Fergus Henderson
99184d3578 Implement support for types with user-defined equality predicates.
Estimated hours taken: 30

Implement support for types with user-defined equality predicates.

Types with user-defined equality predicates are called "non-canonical types";
they may have more than one representation for the same abstract value.
That means that any attempt to deconstruct a value of a non-canonical
type, i.e. any attempt to peek at the representation, must be cc_multi.

This also implies that conceptually speaking, non-canonical types are not
members of the type classes `comparable' (compare/3) or `deconstructible'
(index/2, argument/3, functor/3, deconstruct/5).  Since we don't support
type classes yet, that just means that the type-class checking is done
at runtime, i.e. any call to one of those functions for a non-canonical
type will call error/1 or fatal_error().

To make non-canonical types useful, we really need type classes,
so that the user can provide instance definitions for `comparable'
and `deconstructible' for such types.  It might also be a good idea
to have a type-class `canonicalizable' which provides a function
to convert its argument to some canonical type (that would
require existential types to do nicely, but alternatively we could
just use `univ').

Note that currently the only mechanism for promising that things are
unique is via the C interface.

compiler/det_analysis.m:
	Add code to check unifications that examine the
	representation of a type with a user-defined equality predicate.
	Any such unification must occur in a single-solution context and
	must not be able to fail.  Such unifications determinism have
	determinism cc_multi.

compiler/det_report.m:
	Add code to report errors for misuse of types with user-defined
	equality predicates.  (Also some other stylistic improvements:
	split up a complicated predicate into subroutines, and
	avoid some unnecessary code duplication.)

compiler/prog_data.m:
compiler/hlds_data.m:
	Add a new `maybe(sym_name)' field to the du_type/3 constructor
	to hold the name of the user-defined equality pred for the
	type, if any.

compiler/prog_io.m:
	Add code to parse the new `... where equality is <name>.' syntax.
	Delete the old support for `... where <condition>'.

compiler/hlds_out.m:
compiler/mercury_to_mercury.m:
compiler/mercury_to_goedel.m:
	Print out the new field.

compiler/base_type_layout.m:
compiler/code_util.m:
compiler/dense_switch.m:
compiler/equiv_type.m:
compiler/intermod.m:
compiler/make_hlds.m:
compiler/mode_util.m:
compiler/module_qual.m:
compiler/modules.m:
compiler/switch_detection.m:
compiler/tag_switch.m:
compiler/type_util.m:
compiler/typecheck.m:
compiler/unify_gen.m:
	Trivial changes to ignore (or leave unchanged)
	the new field in `du_type'.

compiler/modecheck_unify.m:
	Pass the term__context to unify_proc__request_unify.

compiler/typecheck.m:
	Typecheck the compiler-generated unify predicates for types
	with user-defined equality preds.

compiler/unify_proc.m:
	For d.u. types, if the type has a user-defined equality predicate
	then generate code for the compiler-generated unify predicate
	that just calls the specified predicate, and generate
	code for the compiler-generated compare and index predicates
	that just calls some procedures in mercury_builtin.m that
	report appropriate error messages.
	Ensure that the automatically-generated predicates
	have appropriate term__contexts everywhere, so that if
	the user-defined equality predicate name is ambiguous,
	non-existent, or has the wrong type, mode, or determinism,
	then the error messages from type checking, mode checking,
	or determinism checking refer to the type declaration.

library/mercury_builtin.m:
	Add predicates builtin_index_non_canonical_type/2
	and builtin_compare_non_canonical_type/2, used by
	the code generated by compiler/unify_proc.m.

doc/reference_manual.texi:
	Document the support for user-defined equality predicates.

library/std_util.m:
	Change ML_expand() to return an indication of whether or not
	the type is a non-canonical type (one with a user-defined
	equality predicate).  Change argument/2, functor/2, and
	deconstruct/4 to abort if called for a non-canonical type.
1997-08-22 13:57:43 +00:00
Fergus Henderson
04b720630b Update the copyright messages so that (a) they contain the correct years
and (b) they say "Copyright (C) ... _The_ University of Melbourne".
1997-07-27 15:09:59 +00:00