Commit Graph

139 Commits

Author SHA1 Message Date
Zoltan Somogyi
181ada0dbf Avoid -O<n> resetting previously set options.
This implements Mantis feature request #495.

NEWS:
    Announce the change.

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

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

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

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

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

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

    Change the interface of special_handler to make the above possible.

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

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

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

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

    Add some XXXs.

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

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

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

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

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

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

    In an unrelated change, factor out a duplicate call.
2020-09-28 18:16:13 +10:00
Zoltan Somogyi
d49f6eab84 Add missing imports of parent modules.
These imports were missing from source files, but were included in imported
modules' .int3 files. An upcoming change will delete these from those .int3
files.
2019-03-20 03:57:10 +11:00
Zoltan Somogyi
b06b2621b3 Move towards packing args with secondary tags.
compiler/hlds_data.m:
    Add bespoke types to record information about local and remote secondary
    tags. The one for local secondary tags includes the value of the
    primary and secondary tag together, since construct unifications
    need to assign this value, and it is better to compute this once,
    instead leaving the target language compiler to do it, potentially
    many times.

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

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

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

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

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

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

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

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

library/uint8.m:
library/uint16.m:
library/uint32.m:
library/uint64.m:
    Add predicates to cast from each of these types to uint.
2018-06-06 03:35:20 +02:00
Zoltan Somogyi
24b98fdafe Pack sub-word-sized ints and dummies in terms.
Previously, the only situation in which we could pack two or more arguments
of a term into a single word was when all those arguments are enums. This diff
changes that, so that the arguments can also be sub-word-sized integers
(signed or unsigned), or values of dummy types (which occupy zero bits).

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

    Handle the new dummy_tag.

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

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

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

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

    Delete an unused predicate.

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

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

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

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

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

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

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

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

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

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

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

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

    Conform to the changes above.

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

    Add notes about possible optimizations.

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

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

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

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

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

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

    Generate slightly better formatted output.

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

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

    Conform to the changes above.

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

compiler/llds_out_util.m:
    Add a comment.

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

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

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

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

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

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

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

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

    Give a macro a more descriptive name.

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

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

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

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

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

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

tests/hard_coded/Mmakefile:
    Enable the new test case.
2018-05-05 13:22:19 +02:00
Zoltan Somogyi
15aa457e12 Delete $module arg from calls to unexpected. 2018-04-07 18:25:43 +10:00
Julien Fischer
f519e26173 Add builtin 64-bit integer types -- Part 1.
Add the new builtin types: int64 and uint64.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

    Update the Java list of TypeCtorRep constants here.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

     Add the mapping from the new types to their target language types.
     These are commented out for now.
2018-01-12 09:29:24 -05:00
Julien Fischer
8a240ba3f0 Add builtin 8, 16 and 32 bit integer types -- Part 1.
Add the new builtin types: int8, uint8, int16, uint16, int32 and uint32.
Support for these new types will need to be bootstrapped over several changes.
This is the first such change and does the following:

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

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

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

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

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

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

    Add builtin operations for all the new types.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

    Update the Java list of TypeCtorRep constants.

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

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

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

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

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

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

runtime/mercury_builtin_types.[ch]:
runtime/mercury_builtin_types_proc_layouts.h:
runtime/mercury_construct.c:
runtime/mercury_deconstruct.c:
runtime/mercury_deep_copy_body.h:
runtime/mercury_ml_expand_body.h
runtime/mercury_table_type_body.h:
runtime/mercury_tabling_macros.h:
runtime/mercury_tabling_preds.h:
runtime/mercury_term_size.c:
runtime/mercury_unify_compare_body.h:
    Add the new builtin types and handle them throughout the runtime.
2017-07-18 01:31:01 +10:00
Julien Fischer
092e175f45 Add a builtin unsigned word sized integer type -- Part 1.
Add a new builtin type: uint, which is an unsigned word sized integer type.
Support for this new type will need be bootstrapped over several changes.
This is the first such change and does the following:

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

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

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

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

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

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

    Bump the RTTI version number here.

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

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

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

    Map uints onto MR_Unsigned.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

    Add an alternative for uints to the tyepctor rep enum.

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

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

runtime/mercury_term_size.c:
runtime/mercury_ml_expand_body.h:
    Handle uint and fix probable bugs with the handling of ints on
    64-bit Windows.
2016-10-24 12:55:35 +11:00
Zoltan Somogyi
2649e3c5a0 Avoid using some Mercury keywords.
compiler/jumpopt.m:
compiler/table_gen.m:
    Avoid using "specified" as a function symbol.

compiler/unused_args.m:
    Avoid using "unused_args" as a function symbol.

compiler/termination.m:
    Fix a comment.
2016-05-13 13:35:13 +10:00
Zoltan Somogyi
4ebc3ffa04 Carve four modules out of prog_data.m.
The prog_data.m module is imported by most modules of the compiler; by
359 modules out of 488, to be exact. Yet it has many parts that most of
those 359 modules don't need. This diff puts those parts into four new
modules. The number of imports of these modules:

    348 modules import prog_data.m
     84 modules import prog_data_foreign.m
     62 modules import prog_data_pragma.m
     12 modules import prog_data_event.m
      5 modules import prog_data_used_modules.m

compiler/prog_data_event.m:
compiler/prog_data_foreign.m:
compiler/prog_data_pragma.m:
compiler/prog_data_used_modules.m:
    New modules. They contain the parts of the parse tree that deal
    respectively with the specification of events and event sets,
    interfacing to foreign languages, pragmas, and the sets of used
    (i.e. not unused) modules.

compiler/prog_data.m:
    Delete the stuff that is now in the new modules. Put the remaining parts
    of the module into a logical order.

compiler/parse_tree.m:
compiler/notes/compiler_design.html:
    Include and document the new modules.

compiler/globals.m:
    Move a type here from prog_data.m, since this is where it belongs.

compiler/add_foreign_proc.m:
compiler/add_mutable_aux_preds.m:
compiler/add_pragma.m:
compiler/add_solver.m:
compiler/add_trail_ops.m:
compiler/call_gen.m:
compiler/code_gen.m:
compiler/code_loc_dep.m:
compiler/comp_unit_interface.m:
compiler/compile_target_code.m:
compiler/complexity.m:
compiler/continuation_info.m:
compiler/coverage_profiling.m:
compiler/ctgc.datastruct.m:
compiler/ctgc.livedata.m:
compiler/ctgc.selector.m:
compiler/deep_profiling.m:
compiler/dep_par_conj.m:
compiler/deps_map.m:
compiler/det_analysis.m:
compiler/det_report.m:
compiler/elds_to_erlang.m:
compiler/equiv_type.m:
compiler/erl_call_gen.m:
compiler/exception_analysis.m:
compiler/export.m:
compiler/fact_table.m:
compiler/foreign.m:
compiler/frameopt.m:
compiler/get_dependencies.m:
compiler/goal_form.m:
compiler/goal_util.m:
compiler/granularity.m:
compiler/hlds_goal.m:
compiler/hlds_module.m:
compiler/hlds_out_goal.m:
compiler/hlds_out_module.m:
compiler/hlds_out_pred.m:
compiler/hlds_pred.m:
compiler/inlining.m:
compiler/intermod.m:
compiler/ite_gen.m:
compiler/item_util.m:
compiler/jumpopt.m:
compiler/layout.m:
compiler/layout_out.m:
compiler/live_vars.m:
compiler/livemap.m:
compiler/llds.m:
compiler/llds_out_file.m:
compiler/llds_out_global.m:
compiler/llds_out_instr.m:
compiler/make.dependencies.m:
compiler/make.module_dep_file.m:
compiler/make_hlds.m:
compiler/make_hlds_warn.m:
compiler/mark_tail_calls.m:
compiler/mercury_compile_llds_back_end.m:
compiler/mercury_compile_main.m:
compiler/ml_call_gen.m:
compiler/ml_code_gen.m:
compiler/ml_code_util.m:
compiler/ml_foreign_proc_gen.m:
compiler/ml_proc_gen.m:
compiler/ml_tailcall.m:
compiler/ml_unify_gen.m:
compiler/mlds.m:
compiler/mlds_to_c.m:
compiler/mlds_to_cs.m:
compiler/mlds_to_java.m:
compiler/modecheck_goal.m:
compiler/module_imports.m:
compiler/module_qual.m:
compiler/module_qual.qualify_items.m:
compiler/modules.m:
compiler/opt_debug.m:
compiler/par_conj_gen.m:
compiler/parse_pragma.m:
compiler/parse_tree_out_info.m:
compiler/parse_tree_out_pragma.m:
compiler/pd_cost.m:
compiler/polymorphism.m:
compiler/pragma_c_gen.m:
compiler/proc_gen.m:
compiler/prog_ctgc.m:
compiler/prog_event.m:
compiler/prog_foreign.m:
compiler/prog_item.m:
compiler/prog_out.m:
compiler/prog_util.m:
compiler/purity.m:
compiler/rbmm.points_to_analysis.m:
compiler/rbmm.points_to_graph.m:
compiler/simplify_goal_call.m:
compiler/simplify_goal_scope.m:
compiler/simplify_proc.m:
compiler/smm_common.m:
compiler/stack_layout.m:
compiler/structure_reuse.analysis.m:
compiler/structure_reuse.direct.choose_reuse.m:
compiler/structure_reuse.direct.detect_garbage.m:
compiler/structure_reuse.domain.m:
compiler/structure_reuse.indirect.m:
compiler/structure_sharing.analysis.m:
compiler/structure_sharing.domain.m:
compiler/table_gen.m:
compiler/tabling_analysis.m:
compiler/term_constr_build.m:
compiler/term_constr_initial.m:
compiler/term_constr_main.m:
compiler/term_constr_main_types.m:
compiler/term_constr_pass2.m:
compiler/term_constr_util.m:
compiler/term_errors.m:
compiler/term_pass1.m:
compiler/term_pass2.m:
compiler/term_traversal.m:
compiler/term_util.m:
compiler/termination.m:
compiler/trace_gen.m:
compiler/trailing_analysis.m:
compiler/type_constraints.m:
compiler/typecheck.m:
compiler/unique_modes.m:
compiler/unused_args.m:
compiler/unused_imports.m:
compiler/use_local_vars.m:
compiler/write_deps_file.m:
    Conform to the changes above.
2016-03-13 18:19:31 +11:00
Zoltan Somogyi
5890311825 Fix some unused predicate warnings.
browser/browse.m:
browser/declarative_edt.m:
compiler/continuation_info.m:
compiler/hlds_out_goal.m:
compiler/llds_out_file.m:
compiler/make.dependencies.m:
compiler/ml_closure_gen.m:
compiler/ml_elim_nested.m:
compiler/options_file.m:
compiler/prog_io_pragma.m:
deep_profiler/html_format.m:
    Delete some dead predicates that won't be needed anymore.

compiler/hlds_goal.m:
compiler/jumpopt.m:
    Comment out some dead predicates that may be needed later.

compiler/matching.m:
compiler/typecheck.m:
compiler/write_deps_file.m:
compiler/write_module_interface_files.m:
    Convert some dead predicates into live predicates by adding calls to them
    at their intended call sites. In some cases the missing call was a sort-of
    bug (the code worked, but not as well as it should have). In others, the
    call was intended only for debugging, and the new call is in a trace scope
    that is disabled by default.

compiler/ml_foreign_proc_gen.m:
    Add an XXX comment about a dead procedure.
2015-12-06 09:49:53 +11:00
Julien Fischer
94535ec121 Fix spelling and formatting throughout the system.
configure.ac:
browser/*.m:
compiler/*.m:
deep_profiler/*.m:
library/*.m:
ssdb/*.m:
runtime/mercury_conf.h.in:
runtime/*.[ch]:
scripts/Mmake.vars.in:
trace/*.[ch]:
util/*.c:
	Fix spelling and doubled-up words.

	Delete trailing whitespace.

	Convert tabs into spaces (where appropriate).
2015-12-02 18:46:14 +11:00
Zoltan Somogyi
a80afc7fb1 More style fixes for the LLDS backend.
compiler/continuation_info.m:
    Give predicates more meaningful names. Pass c_procedures as a whole,
    not in pieces. Put arguments in a more consistent order.

compiler/jumpopt.m:
    Replace a maybe(pair(...)) with a purpose-specific type.

compiler/llds.m:
    Put related arguments of c_proceduress next to each other.

compiler/optimize.m:
    Give names to the fields of the opt_debug_info type.

    Give meaningful names to some variables.

compiler/mercury_compile_llds_back_end.m:
compiler/proc_gen.m:
compiler/transform_llds.m:
    Conform to the above changes.
2015-09-21 11:31:35 +10:00
Zoltan Somogyi
0d31eaf4c3 Convert (C->T;E) to (if C then T else E). 2015-09-21 05:47:55 +10:00
Zoltan Somogyi
1ea38d9595 Clean up some more compiler modules.
compiler/equiv_type.m:
    Don't export a predicate that does not need to be exported.

compiler/hlds_data.m:
compiler/polymorphism.m:
mdbcomp/goal_path.m:
    Put knowledge of the goal_id to hand head constraints in only one place:
    mdbcomp/goal_path.m.

compiler/goal_path.m:
    Allocate goal_ids using counters.

compiler/foreign.m:
    Delete an unused predicate.

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

compiler/equiv_type_hlds.m:
compiler/error_util.m:
compiler/exception_analysis.m:
compiler/global_data.m:
compiler/globals.m:
compiler/goal_expr_to_goal.m:
compiler/goal_form.m:
compiler/granularity.m:
compiler/hlds_args.m:
compiler/hlds_out_util.m:
compiler/interval.m:
compiler/java_names.m:
compiler/jumpopt.m:
compiler/labelopt.m:
compiler/lambda.m:
compiler/lco.m:
compiler/live_vars.m:
compiler/livemap.m:
compiler/modecheck_conj.m:
compiler/type_constraints.m:
    Minor style cleanups.
2015-01-07 23:14:48 +11:00
Peter Wang
4d38590690 Construct partially instantiated direct arg functor values.
Construction unifications of partially instantiated values involving direct
argument functors (where the single argument is free) did not generate any code
in both low-level and high-level backends.  Incorrect behaviour could result if
the program tried to deconstruct the value at run-time.

Also, in the LLDS backend, such a construction unification did not enter the
variable into the var_state_map, leading to a compiler abort when the variable
is looked up.

compiler/ml_unify_gen.m:
	Generate code for constructions of a direct arg functor with free
	argument.  This amounts to assigning a variable to a tagged null
	pointer.

compiler/llds.m:
	Add an rval option `mkword_hole', which is like `mkword' but the
	pointer to be tagged is unspecified.

compiler/unify_gen.m:
	Assign a variable to an `mkword_hole' rval, for a construction
	unification of a direct arg functor with a free argument.

	Reassign the variable to an `mkword' rval when the argument becomes
	bound in a later unification.

compiler/code_info.m:
compiler/var_locn.m:
	Add a predicate to reassign a variable from a `mkword_hole' expression
	to a `mkword' expression.

compiler/llds_out_data.m:
	Write out `mkword_hole' values as a tagged null pointer in C code.

compiler/call_gen.m:
compiler/code_util.m:
compiler/dupelim.m:
compiler/dupproc.m:
compiler/exprn_aux.m:
compiler/global_data.m:
compiler/jumpopt.m:
compiler/livemap.m:
compiler/llds_to_x86_64.m:
compiler/middle_rec.m:
compiler/opt_debug.m:
compiler/opt_util.m:
compiler/peephole.m:
compiler/stack_layout.m:
	Conform to addition of `mkword_hole'.

tests/hard_coded/Mmakefile:
tests/hard_coded/direct_arg_partial_inst.exp:
tests/hard_coded/direct_arg_partial_inst.m:
tests/hard_coded/direct_arg_partial_inst2.exp:
tests/hard_coded/direct_arg_partial_inst2.m:
	Add test cases.
2013-02-14 16:37:04 +11:00
Zoltan Somogyi
4bcfa09630 Speed up the compiler by 0.8% when generating low level C code
Estimated hours taken: 0.5
Branches: main

compiler/frameopt.m:
compiler/jumpopt.m:
compiler/labelopt.m:
compiler/optimize.m:
	Speed up the compiler by 0.8% when generating low level C code
	by using 234 trees instead of lists to store sets of labels.
2012-04-24 04:43:31 +00:00
Peter Wang
2ccac171dd Add float registers to the Mercury abstract machine, implemented as an
Branches: main

Add float registers to the Mercury abstract machine, implemented as an
array of MR_Float in the Mercury engine structure.

Float registers are only useful if a Mercury `float' is wider than a word
(i.e. when using double precision floats on 32-bit platforms) so we let them
exist only then.  In other cases floats may simply be passed via the regular
registers, as before.

Currently, higher order calls still require the use of the regular registers
for all arguments.  As all exported procedures are potentially the target of
higher order calls, exported procedures must use only the regular registers for
argument passing.  This can lead to more (un)boxing than if floats were simply
always boxed.  Until this is solved, float registers must be enabled explicitly
with the developer only option `--use-float-registers'.

The other aspect of this change is using two consecutive stack slots to hold a
single double variable.  Without that, the benefit of passing unboxed floats
via dedicated float registers would be largely eroded.


compiler/options.m:
	Add developer option `--use-float-registers'.

compiler/handle_options.m:
	Disable `--use-float-registers' if floats are not wider than words.

compiler/make_hlds_passes.m:
	If `--use-float-registers' is in effect, enable a previous change that
	allows float constructor arguments to be stored unboxed in structures.

compiler/hlds_llds.m:
	Move `reg_type' here from llds.m and `reg_f' option.

	Add stack slot width to `stack_slot' type.

	Add register type and stack slot width to `abs_locn' type.

	Remember next available float register in `abs_follow_vars'.

compiler/hlds_pred.m:
	Add register type to `arg_loc' type.

compiler/llds.m:
	Add a new kind of lval: double-width stack slots.
	These are used to hold double-precision floating point values only.

	Record setting of `--use-float-registers' in exprn_opts.

	Conform to addition of float registers and double stack slots.

compiler/code_info.m:
	Make predicates take the register type as an argument,
	where it can no longer be assumed.

	Remember whether float registers are being used.

	Remember max float register for calls to MR_trace.

	Count double width stack slots as two slots.

compiler/arg_info.m:
	Allocate float registers for procedure arguments when appropriate.

	Delete unused predicates.

compiler/var_locn.m:
	Make predicates working with registers either take the register type as
	an argument, or handle both register types at once.

	Select float registers for variables when appropriate.

compiler/call_gen.m:
	Explicitly use regular registers for all higher-order calls,
	which was implicit before.

compiler/pragma_c_gen.m:
	Use float registers, when available, at the interface between Mercury
	code and C foreign_procs.

compiler/export.m:
	Whether a float rval needs to be boxed/unboxed when assigned to/from a
	register depends on the register type.

compiler/fact_table.m:
	Use float registers for arguments to predicates defined by fact tables.

compiler/stack_alloc.m:
	Allocate two consecutive stack slots for float variables when
	appropriate.

compiler/stack_layout.m:
	Represent double-width stack slots in procedure layout structures.

	Conform to changes.

compiler/store_alloc.m:
	Allocate float registers (if they exist) for float variables.

compiler/use_local_vars.m:
	Substitute float abstract machine registers with MR_Float local
	variables.

compiler/llds_out_data.m:
compiler/llds_out_instr.m:
	Output float registers and double stack slots.

compiler/code_util.m:
compiler/follow_vars.m:
	Count float registers separately from regular registers.

compiler/layout.m:
compiler/layout_out.m:
compiler/trace_gen.m:
	Remember the max used float register for calls to MR_trace().

compiler/builtin_lib_types.m:
	Fix incorrect definition of float_type_ctor.

compiler/bytecode_gen.m:
compiler/continuation_info.m:
compiler/disj_gen.m:
compiler/dupelim.m:
compiler/exprn_aux.m:
compiler/global_data.m:
compiler/hlds_out_goal.m:
compiler/jumpopt.m:
compiler/llds_to_x86_64.m:
compiler/lookup_switch.m:
compiler/opt_debug.m:
compiler/opt_util.m:
compiler/par_conj_gen.m:
compiler/proc_gen.m:
compiler/string_switch.m:
compiler/tag_switch.m:
compiler/tupling.m:
compiler/x86_64_regs.m:
	Conform to changes.

runtime/mercury_engine.h:
	Add an array of fake float "registers" to the Mercury engine structure,
	when MR_Float is wider than MR_Word.

runtime/mercury_regs.h:
	Document float registers in the Mercury abstract machine.

	Add macros to access float registers in the Mercury engine.

runtime/mercury_stack_layout.h:
	Add new MR_LongLval cases to represent double-width stack slots.

	MR_LONG_LVAL_TAGBITS had to be increased to accomodate the new cases,
	which increases the number of integers in [0, 2^MR_LONG_LVAL_TAGBITS)
	equal to 0 modulo 4.  These are the new MR_LONG_LVAL_TYPE_CONS_n cases.

	Add max float register field to MR_ExecTrace.

runtime/mercury_layout_util.c:
runtime/mercury_layout_util.h:
	Extend MR_copy_regs_to_saved_regs and MR_copy_saved_regs_to_regs
	for float registers.

	Understand how to look up new kinds of MR_LongLval: MR_LONG_LVAL_TYPE_F
	(previously unused), MR_LONG_LVAL_TYPE_DOUBLE_STACKVAR,
	MR_LONG_LVAL_TYPE_DOUBLE_FRAMEVAR.

	Conform to the new MR_LONG_LVAL_TYPE_CONS_n cases.

runtime/mercury_float.h:
	Delete redundant #ifdef.

runtime/mercury_accurate_gc.c:
runtime/mercury_agc_debug.c:
	Conform to changes (untested).

trace/mercury_trace.c:
trace/mercury_trace.h:
trace/mercury_trace_declarative.c:
trace/mercury_trace_external.c:
trace/mercury_trace_internal.c:
trace/mercury_trace_spy.c:
trace/mercury_trace_vars.c:
trace/mercury_trace_vars.h:
	Handle float registers in the trace subsystem.  This is mostly a matter
	of saving/restoring them as with regular registers.
2011-10-17 04:31:33 +00:00
Zoltan Somogyi
517fbac88e Add four LLDS instructions Paul will soon need to implement the loop control
Estimated hours taken: 8
Branches: main

Add four LLDS instructions Paul will soon need to implement the loop control
transformation.

compiler/llds.m:
	Add the new instructions.

compiler/llds_out_instr.m:
	Output the new instructions. Paul may want to change the code
	we generate.

compiler/dupelim.m:
compiler/dupproc.m:
compiler/exprn_aux.m:
compiler/global_data.m:
compiler/jumpopt.m:
compiler/livemap.m:
compiler/llds_to_x86_64.m:
compiler/middle_rec.m:
compiler/opt_debug.m:
compiler/opt_util.m:
compiler/peephole.m:
compiler/reassign.m:
compiler/use_local_vars.m:
	Handle the new instructions.

	In opt_util.m, fix two old bugs. First, the restore_maxfr instruction
	behaved as if it updated hp, not maxfr. Second, the keep_assign
	instruction wasn't being handled as an assignment operation.

	In peephole.m, fix an old bug, in which assignments through mem_refs
	were not considered to invalidate the cached value of an lval.

	In use_local_vars, fix an old bug: the keep_assign instruction
	wasn't being handled as an assignment operation. Assignments
	themselves weren't being as optimized as they could be.
2011-09-30 05:53:51 +00:00
Paul Bone
58e305e4c0 Implement the source-to-source part of the loop control transformation. The
remaining part is the code generation for code that is to be spawned off.  It
must be handled in the code generator since it uses the parent stack pointer in
many cases.

I'm committing this now so that Zoltan can begin to review it while I work on
the code generator component.

compiler/par_loop_control.m:
    This new file contains the source-to-source part of the parallel loop
    control transformation..

compiler/transform_hlds.m.
    Include the par_loop_control module within the transform_hlds module.

compiler/mercury_compile_middle_passes.m:
    Call the loop control transformation at stage 206 - after the dependant
    parallel conjunction transformation.

    Move the last call optimisation pass from stage 175 to 206 since it will
    most-likely prevent loop control from working.  Where both transformations
    are applicable, the loop control transformation is preferred.

compiler/options.m:
    Add new options for loop control.

compiler/handle_options.m:
    Disable loop control if we're not in a grade that supports parallel
    conjunctions.

    Other tests that should have been testing for parallel conjunction support
    but only tested parallel support have been fixed.

compiler/hlds_goal.m:
    Add the feature_do_not_tailcall feature.

compiler/call_gen.m:
    Mark LLCS call goals that may not have last call optimisation applied to
    them if they have the feature_do_not_tailcall feature set in their HLDS
    info.

compiler/goal_util.m:
    Create a new predicate expand_plain_conj, this returns a list of the sub
    goals of a plain conjunction, or returns the goal in a singleton list.
    XXX: Could someone review the name of this predicate.

compiler/hlds_pred.m:
    Add a symbol for the new transformation in the pred_transformation type.

    Corrected a comment to match the arguments in the predicate it refers to.

compiler/prog_util.m:
    Add support to make_pred_name for creating names for loop control
    predicates.

compiler/dep_par_conj.m:
    Fix grammer in a comment.

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

compiler/layout_out.m:
    Conform to the change in hlds_pred.m

runtime/mercury_par_builtin.[ch]:
    Add support for lc_wait_free_slot/2, the blocking version of
    lc_get_free_slot/2.  This means that other loop control builtins have
    changed, for instance, lc_join_and_terminate/2 must wake up a context
    blocked in lc_wait_free_slot/2 after making the slot it was using free.

    Use a spin lock in the loop control structure rather than a POSIX mutex.

runtime/mercury_wrapper.[ch]:
    Add support for a runtime variable, the number of contexts per loop control.
    This can be controlled with a MERCURY_OPTIONS option.

mdbcomp/program_representation.m:
    Include lc_wait_free_slot/2 in the list of external predicates.

mdbcomp/mdbcomp.goal_path.m:
    Add two new predicates goal_path_remove_first/3 and goal_path_get_first/2.

library/par_builtin.m:
    Add new builtins to support the loop control transformation:

        lc_wait_free_slot/2 will block the context until a new slot is
        available.

        lc_default_num_contexts/1 will return the number of contexts to use, by
        default, for a loop-controlled loop.

    Add myself as an author of this module.

doc/user_guide.texi:
    Document the runtime --num-contexts-per-lc-per-thread option.  It is
    currently commented out since it is not intended for users, at least for
    now.

    Document the loop control options for the compiler.

---

The change below was written by Zoltan, I reviewed when I applied his diff to
my workspace.

Allow the compiler to mark calls in the LLDS as calls that cannot have last
call optimization applied to them. Paul will soon need this capability
in order to implement parallel conjunctions in which earlier conjuncts
are spawned off, and later conjuncts contain recursive calls, but the
earlier conjuncts need the stack frame.

compiler/llds.m:
        Add a flag to det and semi calls. (Model_non calls have had a similar
        flag for a long time, for a totally different reason.)

compiler/call_gen.m:
        By default, say that det and semi calls may have LCO applied to them.

compiler/jumpopt.m:
        Apply LCO to det and semi calls only if this flag allows it.

compiler/opt_debug.m:
        Include the flag in debugging dumps.
2011-09-27 00:49:27 +00:00
Zoltan Somogyi
295415090e Convert almost all remaining modules in the compiler to use
Estimated hours taken: 6
Branches: main

compiler/*.m:
	Convert almost all remaining modules in the compiler to use
	"$module, $pred" instead of "this_file" in error messages.

	In a few cases, the old error message was misleading, since it
	contained an incorrect, out-of-date or cut-and-pasted predicate name.

tests/invalid/unresolved_overloading.err_exp:
	Update an expected output containing an updated error message.
2011-05-23 05:08:24 +00:00
Peter Wang
7e26b55e74 Implement a new form of memory profiling, which tells the user what memory
Branches: main

Implement a new form of memory profiling, which tells the user what memory
is being retained during a program run.  This is done by allocating an extra
word before each cell, which is used to "attribute" the cell to an
allocation site.  The attribution, or "allocation id", is an address to an
MR_AllocSiteInfo structure generated by the Mercury compiler, giving the
procedure, filename and line number of the allocation, and the type
constructor and arity of the cell that it allocates.

The user must manually instrument the program with calls to
`benchmarking.report_memory_attribution', which forces a GC and summarises
the live objects on the heap using the attributions.  The mprof tool is
extended with a new mode to parse and present that data.

Objects which are unattributed (e.g. by hand-written C code which hasn't
been updated) are still accounted for, but show up in profiles as "unknown".

Currently this profiling mode only works in conjunction with the Boehm
garbage collector, though in principle it can work with any memory allocator
for which we can access a list of the live objects.  Since term size
profiling relies on the same technique of using an extra word per memory
cell, the two profiling modes are incompatible.

The output from `mprof -s' looks like this:

------ [1] some label ------
   cells            words         cumul  procedure / type (location)
   14150            38872                total

*   1949/ 13.8%      4872/ 12.5%  12.5%  <predicate `parser.parse_rest/7' mode 0>
     975/  6.9%      1950/  5.0%         list.list/1 (parser.m:502)
     487/  3.4%      1948/  5.0%         term.term/1 (parser.m:501)
     487/  3.4%       974/  2.5%         term.const/0 (parser.m:501)

*   1424/ 10.1%      4272/ 11.0%  23.5%  <predicate `parser.parse_simple_term_2/6' mode 0>
     708/  5.0%      2832/  7.3%         term.term/1 (parser.m:643)
     708/  5.0%      1416/  3.6%         term.const/0 (parser.m:643)
...


boehm_gc/alloc.c:
boehm_gc/include/gc.h:
boehm_gc/misc.c:
boehm_gc/reclaim.c:
	Add a callback function to be called for every live object after a GC.

	Add a function to write out the GC_size_map array.

compiler/layout.m:
	Define the alloc_site_info type which is equivalent to the
	MR_AllocSiteInfo C structure.

	Add alloc_site_array as a kind of "layout" array.

compiler/llds.m:
	Add allocation sites to `cfile' structure.

	Replace TypeMsg argument (which was also for profiling) on `incr_hp'
	instructions by an allocation site identifier.

	Add a new foreign_proc_component for allocation site ids.

compiler/code_info.m:
compiler/global_data.m:
compiler/proc_gen.m:
	Keep the set of allocation sites in the code_info and global_data
	structures.

compiler/unify_gen.m:
	Add allocation sites to LLDS allocation instructions.

compiler/layout_out.m:
compiler/llds_out_file.m:
compiler/llds_out_instr.m:
	Output MR_AllocSiteInfo arrays in generated C files.

	Output code to register the MR_AllocSiteInfo array with the Mercury
	runtime.

	Output allocation site ids for memory allocation instructions.

compiler/llds_out_util.m:
	Add allocation sites to llds_out_info.

compiler/pragma_c_gen.m:
compiler/ml_foreign_proc_gen.m:
	Generate a macro MR_ALLOC_ID which resolves to an allocation site
	structure, for every foreign_proc whose C code contains the string
	"MR_ALLOC_ID".  This is to be used by hand-written C code which
	allocates memory.

	MR_PROC_LABELs are retained for backwards compatibility.  Though
	they were introduced for profiling, they seem to have been co-opted
	for printf-debugging since then.

compiler/ml_global_data.m:
	Add allocation site structures to the MLDS global data.

compiler/mlds.m:
compiler/ml_unify_gen.m:
	Add allocation site id to `new_object' instruction.

compiler/mlds_to_c.m:
	Output allocation site arrays and allocation ids in high-level C code.

	Output a call to register the allocation site array with the Mercury
	runtime.

	Delete an unused predicate.

compiler/exprn_aux.m:
compiler/jumpopt.m:
compiler/livemap.m:
compiler/mercury_compile_llds_back_end.m:
compiler/middle_rec.m:
compiler/ml_accurate_gc.m:
compiler/ml_elim_nested.m:
compiler/ml_optimize.m:
compiler/ml_util.m:
compiler/mlds_to_cs.m:
compiler/mlds_to_gcc.m:
compiler/mlds_to_il.m:
compiler/mlds_to_java.m:
compiler/mlds_to_managed.m:
compiler/opt_debug.m:
compiler/opt_util.m:
compiler/use_local_vars.m:
compiler/var_locn.m:
	Conform to changes.

compiler/pickle.m:
compiler/prog_event.m:
compiler/timestamp.m:
	Conform to changes in memory allocation macros.

library/benchmarking.m:
	Add the `report_memory_attribution' instrumentation predicates.

	Conform to changes to MR_memprof_record.

library/array.m:
library/bit_buffer.m:
library/bitmap.m:
library/construct.m:
library/deconstruct.m:
library/dir.m:
library/io.m:
library/mutvar.m:
library/store.m:
library/string.m:
library/thread.semaphore.m:
library/version_array.m:
	Use attributed memory allocation throughout the standard library so
	that objects don't show up in the memory profile as "unknown".

	Replace MR_PROC_LABEL by MR_ALLOC_ID.

mdbcomp/program_representation.m:
mdbcomp/rtti_access.m:
	Replace MR_PROC_LABEL by MR_ALLOC_ID.

profiler/Mercury.options:
profiler/globals.m:
profiler/mercury_profile.m:
profiler/options.m:
profiler/output.m:
profiler/snapshots.m:
	Add a new mode to `mprof' to parse and present the data from
	`Prof.Snapshots' files.

	Add options for the new profiling mode.

profiler/process_file.m:
	Fix a typo.

runtime/mercury_conf_param.h:
	#define MR_MPROF_PROFILE_MEMORY_ATTRIBUTION if memory profiling
	is enabled and we are using Boehm GC.

runtime/mercury.h:
	Make MR_new_object take an allocation id argument.

	Conform to changes in memory allocation macros.

runtime/mercury_memory.c:
runtime/mercury_memory.h:
runtime/mercury_types.h:
	Define MR_AllocSiteInfo.

	Add memory allocation functions and macros which take into the
	account the additional word necessary for the new profiling mode.
	These should be used in preferences to the raw memory allocation
	functions wherever possible so that objects do not show up in the
	profile as "unknown".

	Add analogues of realloc/free which take into account the offset
	introduced by the attribution word.

	Add function versions of the MR_new_object macros, which can't be
	written in standard C.  They are only used when necessary.

	Add built-in allocation site ids, to be used in the runtime and
	other hand-written code when context-specific ids are unavailable.

runtime/mercury_heap.h:
	Make MR_tag_offset_incr_hp_msg and MR_tag_offset_incr_hp_atomic_msg
	allocate an extra word when memory attribution is desired, and store
	the allocation id there.

	Similarly for MR_create{1,2,3}_msg.

	Replace proclabel arguments in allocation macros by alloc_id
	arguments.

	Replace MR_hp_alloc_atomic by MR_hp_alloc_atomic_msg.  It was only
	used for boxing floats.

	Conform to change to MR_new_object macro.

runtime/mercury_bootstrap.h:
	Delete obsolete macro hp_alloc_atomic.

runtime/mercury_heap_profile.c:
runtime/mercury_heap_profile.h:
	Add the code to summarise the live objects on the Boehm GC heap and
	writes out the data to `Prof.Snapshots', for display by mprof.

	Don't store the procedure name in MR_memprof_record: the procedure
	address is enough and faster to compare.

runtime/mercury_prof.c:
	Finish and close the `Prof.Snapshots' file when the program
	terminates.

	Conform to changes in MR_memprof_record.

runtime/mercury_misc.h:
	Add a macro to expand to the name of the allocation sites array
	in LLDS grades.

runtime/mercury_bitmap.c:
runtime/mercury_bitmap.h:
	Pass allocation id through bitmap allocation functions.

	Delete unused function MR_string_to_bitmap.

runtime/mercury_string.h:
	Add MR_make_aligned_string_copy_msg.

	Make string allocation macros take allocation id arguments.

runtime/mercury.c:
runtime/mercury_array_macros.h:
runtime/mercury_context.c:
runtime/mercury_deconstruct.c:
runtime/mercury_deconstruct_macros.h:
runtime/mercury_dlist.c:
runtime/mercury_engine.c:
runtime/mercury_float.h:
runtime/mercury_hash_table.c:
runtime/mercury_ho_call.c:
runtime/mercury_label.c:
runtime/mercury_prof_mem.c:
runtime/mercury_stacks.c:
runtime/mercury_stm.c:
runtime/mercury_string.c:
runtime/mercury_thread.c:
runtime/mercury_trace_base.c:
runtime/mercury_trail.c:
runtime/mercury_type_desc.c:
runtime/mercury_type_info.c:
runtime/mercury_wsdeque.c:
	Use attributed memory allocation throughout the runtime so that
	objects don't show up in the profile as "unknown".

runtime/mercury_memory_zones.c:
	Attribute memory zones to the Mercury runtime.

runtime/mercury_tabling.c:
runtime/mercury_tabling.h:
	Use attributed memory allocation macros for tabling structures.

	Delete unused MR_table_realloc_* and MR_table_copy_bytes macros.

runtime/mercury_deep_copy_body.h:
	Try to retain the original attribution word when copying values.

runtime/mercury_ml_expand_body.h:
	Conform to changes in memory allocation macros.

runtime/mercury_tags.h:
	Replace proclabel arguments by alloc_id arguments in allocation macros.

runtime/mercury_wrapper.c:
	If memory attribution is enabled, tell Boehm GC that pointers may be
	displaced by an extra word.

trace/mercury_trace.c:
trace/mercury_trace_tables.c:
	Conform to changes in memory allocation macros.

extras/net/tcp.m:
extras/solver_types/library/any_array.m:
extras/trailed_update/tr_array.m:
	Conform to changes in memory allocation macros.

doc/user_guide.texi:
	Document the new profiling mode.

doc/reference_manual.texi:
	Update a commented out example.
2011-05-20 04:16:58 +00:00
Julien Fischer
9f68c330f0 Change the argument order of many of the predicates in the map, bimap, and
Branches: main

Change the argument order of many of the predicates in the map, bimap, and
multi_map modules so they are more conducive to the use of state variable
notation, i.e. make the order the same as in the sv* modules.

Prepare for the deprecation of the sv{bimap,map,multi_map} modules by
removing their use throughout the system.

library/bimap.m:
library/map.m:
library/multi_map.m:
	As above.
NEWS:
	Announce the change.

	Separate out the "highlights" from the "detailed listing" for
	the post-11.01 NEWS.

	Reorganise the announcement of the Unicode support.

benchmarks/*/*.m:
browser/*.m:
compiler/*.m:
deep_profiler/*.m:
extras/*/*.m:
mdbcomp/*.m:
profiler/*.m:
tests/*/*.m:
ssdb/*.m:
samples/*/*.m
slice/*.m:
	Conform to the above change.

	Remove any dependencies on the sv{bimap,map,multi_map} modules.
2011-05-03 04:35:04 +00:00
Paul Bone
322feaf217 Add more threadscope instrumentation.
This change introduces instrumentation that tracks sparks as well as parallel
conjunctions and their conjuncts.  This should hopefully give us more
information to diagnose runtime performance issues.

As of this date the ThreadScope program hasn't been updated to read or
understand these new events.

runtime/mercury_threadscope.[ch]:
    Added a function and types to register all the threadscope strings from an
    array.

    Add functions to post the new events (see below).

runtime/mercury_threadscope.c:
    Added support for 5 new threadscope events.
        Registering a string so that other messages may refer to a constant
        string.

        Marking the beginning and ends of parallel conjunctions.

        Creating a spark for a parallel conjunct.

        Finishing a parallel conjunct.

    Re-arranged event IDs, I've started allocating IDs from 38 onwards for
    general purposes and 100 onwards for mercury specific events after talking
    with Duncan Coutts.

    Trimmed excess whitespace from the end of lines.

runtime/mercury_context.h:
    Post a beginning parallel conjunction message when the sync term for the
    parallel conjunction is initialized.

    Post an event when creating a spark for a parallel conjunction.

    Add a MR_spark_id field to the MR_Spark structure, these identify sparks to
    threadscope.

runtime/mercury_context.c:
    Post threadscope messages when a spark is about to be executed.

    Post a threadscope event when a parallel conjunct is completed.

    Add a missing memory barrier.

runtime/mercury_wrapper.[ch]:
    Create a global function pointer for the code that registers strings in the
    threadscope string table, this is filled in by mkinit.

    Call this function pointer immediatly after setting up threadscope.

runtime/mercury_wsdeque.[ch]:
    Modify MR_wsdeque_pop_bottom to return the spark pointer (which points onto
    the queue) rather then returning a result through a pointer and bool if the
    operation was successful.  This pointer is safe to dereference until
    MR_wsdeque_push_bottom is used.

runtime/mercury_wsdeque.c:
    Corrected a code comment.

runtime/mercury_engine.h:
    Documented some of the fields of the engine structure that hadn't been
    documented.

    Add a next spark ID field to the engine structure.

    Change the type of the engine ID field to MR_uint_least16_t

compiler/llds.m:
    Add a third field to the init_sync_term instruction that stores the index
    into the threadscope string table of the static conjunction ID.

    Add a field to the c_file structure containing the threadscope string
    table.

compiler/layout.m:
    Added a new layout array name for the threadscope string table.

compiler/layout_out.m:
    Implement code to write out the threadscope string table.

compiler/llds_out_file.m:
    Write out the threadscope string table when writing out the c_file.

compiler/par_conj_gen.m:
    Create strings that statically identify parallel conjunctions for each
    init_sync_term LLDS instruction.  These strings are added to a table in the
    !CodeInfo and the index of the string is added to the init_sync_term
    instruction.

    Add an extra instruction after a parallel conjunction to post the message
    that the parallel conjunction has completed.

compiler/global_data.m:
    Add fields to the global data structure to represent the threadscope string
    table and its current size.

    Add predicates to update and retrieve the table.

    Handle merging of threadscope string tables in global data by allowing the
    references to the strings to be remapped.

    Refactored remapping code so that a caller such as proc_gen only needs to
    call one remapping predicate after merging global data..

compiler/code_info.m:
    Add a table of strings for use with threadscope to the code_info_persistent
    type.

    Modify the code_info_init to initialise the threadscope string table fields.

    Add a predicate to get the string table and another to update it.

compiler/proc_gen.m:
    Build the containing goal map before code generation for procedures with
    parallel conjunctions in a parallel grade.  par_conj_gen.m depends on this.

    Conform to changes in code_info.m and global_data.m

compiler/llds_out_instr.m:
    Write out the extra parameter in the init_sync_term instruction.

compiler/dupelim.m:
compiler/dupproc.m:
compiler/exprn_aux.m:
compiler/global_data.m:
compiler/jumpopt.m:
compiler/livemap.m:
compiler/llds_to_x86_64.m:
compiler/mercury_compile_llds_back_end.m:
compiler/middle_rec.m:
compiler/opt_debug.m:
compiler/opt_util.m:
compiler/peephole.m:
compiler/reassign.m:
compiler/use_local_vars.m:
    Conform to changes in llds.m

compiler/opt_debug.m:
    Conform to changes in layout.m

compiler/mercury_compile_llds_back_end.m:
    Fix some trailing whitespace.

util/mkinit.c:
    Build an initialisation function that registers all the strings in
    threadscope string tables.

    Correct the layout of a comment.
2011-03-25 03:13:42 +00:00
Zoltan Somogyi
8a28e40c9b Add the predicates sorry, unexpected and expect to library/error.m.
Estimated hours taken: 2
Branches: main

Add the predicates sorry, unexpected and expect to library/error.m.

compiler/compiler_util.m:
library/error.m:
	Move the predicates sorry, unexpected and expect from compiler_util
	to error.

	Put the predicates in error.m into the same order as their
	declarations.

compiler/*.m:
	Change imports as needed.

compiler/lp.m:
compiler/lp_rational.m:
	Change imports as needed, and some minor cleanups.

deep_profiler/*.m:
	Switch to using the new library predicates, instead of calling error
	directly. Some other minor cleanups.

NEWS:
	Mention the new predicates in the standard library.
2010-12-15 06:30:36 +00:00
Zoltan Somogyi
4db9b2adbf Until now, the only indexing we did for switches on strings was using a hash
Estimated hours taken: 40
Branches: main

Until now, the only indexing we did for switches on strings was using a hash
table containing jump targets (represented as indices into a list of labels).
This diff supplements this with

- binary searches of tables containing jump targets,
- binary searches of tables containing values (lookup tables), and
- hash searches of tables containing values (lookup tables).

For now, the new methods exist in the LLDS backend only.

NEWS:
	Mention the new capability.

compiler/string_switch.m:
	Add predicates that implement the new indexing methods on strings.
	Factor out code from existing predicates as required for this.

compiler/switch_gen.m:
	Invoke the new predicates in string_switch.m when relevant.

	Avoid passing the constant "no" as the initial value of !MaybeEnd
	to predicates where we know this will ALWAYS happen.

compiler/options.m:
doc/user_guide.texi:
	Add an option to control when we use binary searches for switches
	on strings.

compiler/lookup_switch.m:
	This module previously handled lookup switches on integers.
	Generalize it so that pieces of it are now also usable to help
	implement lookup switches on strings. Rename the predicates specific
	to switches on integers to make clear this specificity, and separate
	them from the predicates that help implement lookup switches on
	variables of all the supported types.

	Export some types, predicates and functions for use in string_switch.m.

	Fix the code so that it correctly handles det switches, which
	can happen e.g. if we know the possible set of values of the
	switched-on variable.

	Use tail-recursive code to handle the list of switch arms, to allow us
	to handle very large switches.

	Remove an obsolete comment from the top about a previously implemented
	optimization.

compiler/lookup_util.m:
	Make set_liveness_and_end_branch update MaybeEnd, to account for the
	reservation of stack slots for holding the current and last rows in
	later solutions tables for model_non lookup switches.

compiler/switch_util.m:
	Make the exported predicates of this module more general, making them
	usable for switches on strings as well as ints. Also make them easier
	to use. In one case this meant bundling two predicates that were always
	used together into one predicate. In another, it meant splitting one
	predicate into two, since some of its callers needed an intermediate
	result. In the case of a type, it means reordering its fields
	to make the order match the order of their use in the implementation.

	Add some predicates specifically for switches on strings.

compiler/ml_lookup_switch.m:
compiler/ml_string_switch.m:
compiler/ml_switch_gen.m:
	Conform to the changes to switch_util.m.

compiler/jumpopt.m:
	If the comment associated with a label ends with "nofulljump", then
	inhibit fulljump optimization of jumps to that label. That
	optimization would replace the jumps with the code starting at that
	label. This is avoids the overhead of jump instructions, and it is a
	good idea in the usual case of forward jumps. However, for the few
	backward jumps we generate, the block that replaces the jump
	instruction can actually END with the same jump instruction (which may
	be conditionally executed), which means that our usual repeated
	invocation of jumpopt can replace the original jump instruction
	with MANY copies of the block it jumps to. In some cases, such as those
	in hash switches, you get more copies than can ever be executed in any
	actual execution. Lookup switches therefore now mark the labels that
	are targets of backward jumps with this marker.

compiler/llds.m:
	Document the new behavior of jumpopt.

compiler/code_info.m:
	Export a predicate for use in improving the code we generate for lookup
	switches.

	Make some other predicates simpler and/or more efficient.

compiler/builtin_ops.m:
	Add a builtin op for doing string comparisons by calling strcmp.
	This is to prevent the need for two traversals of the strings being
	compared in each iteration of binary search.

compiler/bytecode.m:
compiler/c_util.m:
compiler/mlds_to_gcc.m:
compiler/mlds_to_il.m:
compiler/llds.m:
compiler/llds_to_x86_64.m:
	Conform to the change in builtin_ops.m.

compiler/disj_gen.m:
	Conform to the change in lookup_util.m

compiler/frameopt.m:
compiler/proc_gen.m:
compiler/unify_gen.m:
	Take advantage of the change in fulljump optimization.

compiler/opt_debug.m:
	Improve the string representation of rvals by recording the types of
	the operands of binary operations, and making the output a bit more
	consistent looking.

compiler/dupproc.m:
compiler/var_locn.m:
	Minor style fixes.

runtime/mercury_string.h:
	Add a version of strcmp for use by our code generator. This version
	casts the arguments before calling the real strcmp. We need it since we
	usually specify the arguments as r1, r2 etc, which are declared as
	MR_Word, not char *.

tests/hard_coded/lookup_disj.{m,exp}:
tests/hard_coded/string_switch.{m,exp}:
	Make these existing tests significantly tougher by making them exercise
	a wider range of use scenarios.

tests/hard_coded/string_switch{2,3}.{m,exp}:
tests/hard_coded/Mercury.options
	While the string_switch test case tests the handling of jump switches,
	these two new test cases test the handling of binary search tables and
	hash tables respectively. Their code is identical to the code of
	the string_switch test case, but Mercury.options causes them to be
	compiled with different options.

tests/hard_coded/int_switch.{m,exp}:
	A new test case, equivalent in structure to the string switch test
	cases, to test the handling of lookup switches on atomic values.
2010-11-01 04:03:06 +00:00
Zoltan Somogyi
92e8ab951a Split up some of the compiler's biggest predicates.
Estimated hours taken: 6
Branches: main

compiler/jumpopt.m:
compiler/type_constraints.m:
compiler/write_dep_file.m:
	Split up some of the compiler's biggest predicates.

	There are no algorithmic changes, but in jumpopt, this diff
	bundles up a bunch of parameters into a single structure.
	This is probably why this diff improves the speed of the compiler
	by 1.8%.

compiler/llds.m:
	Add some insts needed by jumpopt.m.
2010-02-03 23:23:37 +00:00
Zoltan Somogyi
9bdc5db590 Try to work around the Snow Leopard linker's performance problem with
Estimated hours taken: 20
Branches: main

Try to work around the Snow Leopard linker's performance problem with
debug grade object files by greatly reducing the number of symbols needed
to represent the debugger's data structures.

Specifically, this diff groups all label layouts in a module, each of which
previously had its own named global variable, into only a few (one to four)
global variables, each of which is an array. References to the old global
variables are replaced by references to slots in these arrays.

This same treatment could also be applied to other layout structures. However,
most layouts are label layouts, so doing just label layouts gets most of the
available benefit.

When the library and compiler are compiled in grade asm_fast.gc.debug,
this diff leads to about a 1.5% increase in the size of their generated C
source files (from 338 to 343 Mb), but a more significant reduction (about 17%)
in the size of the corresponding object files (from 155 to 128 Mb). This leads
to an overall reduction in disk requirements from 493 to 471 Mb (about 4.5%).
Since we generate the same code and data as before, with the data just being
arranged differently, the decrease in object file sizes is coming from the
reduction in relocation information, the information processed by the linker.
This should speed up the linker.

compiler/layout.m:
	Make the change described above. We now define up to four arrays:
	one each for label layouts with and without information about
	variables, one for the layout structures of user events,
	and one for the variable number lists of user events.

compiler/layout_out.m:
	Generate the new arrays that the module being compiled needs.

	Use purpose-specific types instead of booleans.

compiler/trace_gen.m:
	Use a new field in foreign_proc_code instructions to record the
	identity of any labels whose layout structures we want to refer to,
	even though layout structures have not been generated yet. The labels
	will be looked up in a map (generated together with the layout
	structures) by llds_out.m.

compiler/llds.m:
	Add this extra field to foreign_proc_code instructions.

	Add the map (which is actually in two parts) to the c_file type,
	which is the data structure representing the entire LLDS.

	Also add to the c_file type some other data structures that previously
	we used to hand around alongside it. Some of these data structures
	used to conmingle layout structures that we now separate.

compiler/stack_layout.m:
	Generate array slots instead of separate structures for label layouts.
	Return the different arrays separately.

compiler/llds_out.m:
	Order the output of layout structures to require fewer forward
	declarations. The forward declarations of the few arrays holding the
	label layout structures replace a lot of the declarations previously
	needed.

	Include the information needed by layout_out.m in the llds_out_info,
	and conform to the changes above.

	As a side-effect of all these changes, we now generate proc layout
	structures in the same order as the procedures' appearence in the HLDS,
	which is the same as their order in the source code, modulo any
	procedures added by the compiler itself (for lambdas, unification
	predicates, etc).

compiler/code_info.m:
compiler/dupelim.m:
compiler/dup_proc.m:
compiler/exprn_aux.m:
compiler/frameopt.m:
compiler/global_data.m:
compiler/ite_gen.m:
compiler/jumpopt.m:
compiler/livemap.m:
compiler/llds_to_x86_64.m:
compiler/mercury_compile_llds_back_end.m:
compiler/middle_rec.m:
compiler/opt_debug.m:
compiler/opt_util.m:
compiler/pragma_c_gen.m:
compiler/proc_gen.m:
compiler/reassign.m:
compiler/use_local_vars.m:
	Conform to the changes above.

runtime/mercury_goto.h:
	Add the macros used by the new code in layout_out.m and llds_out.m.
	We need new macros because the old ones assumed that the
	C preprocessor can construct the address of a label's layout structure
	from the name of the label, which is obviously no longer possible.

	Make even existing families of macros handle in bulk up to 10 labels,
	up from the previous 8.

runtime/mercury_stack_layout.h:
	Add macros for use by the new code in layout.m.

tests/debugger/*.{inp,exp}:
tests/debugger/declarative/*.{inp,exp}:
	Update these test cases to account for the new (and better) order
	of proc layout structures. Where inputs changed, this was to ensure
	that we still select the same procedures from lists of procedures,
	e.g. to put a breakpoint on.
2009-10-21 06:36:37 +00:00
Zoltan Somogyi
00ea415659 Implement scalar and vector global data for the MLDS backend, modelled on
Estimated hours taken: 32
Branches: main

Implement scalar and vector global data for the MLDS backend, modelled on
the implementation of global data for the LLDS backend. Use scalar global
data to eliminate redundant copies of static memory cells. Use vector global
data to implement lookup switches, and to implement string switches more
efficiently.

The diff reduces the compiler executable's size by 3.3% by eliminating
duplicate copies of static cells. The diff can reduce the sizes of object files
not only through this reduction in the size of read-only data, but also through
reductions in the size of the needed relocation info: even in the absence of
duplicated cells, using one global variable that holds an array of all the
cells of the same type requires less relocation info than a whole bunch of
separate global variables each holding one cell. If C debugging is enabled,
we can also expect a significant reduction in the size of the debug information
stored in object files AND in executables, for the same reason. (This was the
original motivation for scalar static data on the LLDS backend; the large
amount of relocation information in object files, especially if Mercury
debugging was enabled, led to long link times.)

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

compiler/ml_lookup_switch.m:
	This new module implements lookup switches for the MLDS backend.
	For now, it implements only model_det and model_semi switches.

compiler/ml_switch_gen.m:
	Call the new module when appropriate.

	Do not require the switch generation methods that never generate
	definitions to return an empty list of definitions.

compiler/ml_backend.m:
	Add the new module.

compiler/notes/compiler_design.html:
	Mention the new module, and fix some documentation rot.

compiler/mlds.m:
	Extend the relevant types to allow the generated MLDS code to refer
	to both scalar and vector global data.

	Move a predicate that belongs here from ml_code_util.m.

	Rename a predicate to avoid ambiguity with its own return type.

	Give the functors of some types distinguishing prefixes.

compiler/ml_util.m:
	Replace some semidet predicates with functions returning bool,
	since the semidet predicates silently did the wrong thing on the new
	additions to the MLDS.

compiler/ml_code_gen.m:
	Ensure that we do not generate references to scalar and vector common
	cells on platforms which do not (yet) support them. At the moment,
	they are supported only when generating C.

	Put some code into a predicate of its own.

compiler/builtin_ops.m:
	Extend the type that represents array elements to allow them to be
	structures, which they are for vector globals.

compiler/ml_code_util.m:
	Add some new utility predicates and functions.

	Move some predicates that are now needed in more than one module here.

	Remove the predicates moved to mlds.m.

	Conform to the changes above.

compiler/ml_string_switch.m:
compiler/string_switch.m:
	Instead of two separate arrays, use one array of structures (a static
	vector), since they way, the string and the next slot indicator,
	which are accesses together, are next to each other and thus
	in the same cache block.

compiler/lookup_switch.m:
compiler/switch_util.m:
	Move several predicates from lookup_switch.m to switch_util.m,
	since now ml_lookup_switch.m needs them too. Parameterize the moved
	predicates as needed.

	Conform to the changes above.

compiler/llds.m:
	Add prefixes to some functor names to avoid ambiguities.

compiler/llds_out.m:
compiler/lookup_util.m:
compiler/mercury_compile.m:
	Minor style improvements.

compiler/global_data.m:
	Minor cleanups. Give names to some data types, and add prefixes to some
	field names.

	Conform to the changes above.

compiler/jumpopt.m:
	Minor style improvements.

	Conform to the changes above.

compiler/opt_debug.m:
	Fix some misleading variable names.

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

compiler/ll_pseudo_type_info.m:
compiler/ml_closure_gen.m:
compiler/ml_elim_nested.m:
compiler/ml_optimize.m:
compiler/ml_tag_switch.m:
compiler/ml_tailcall.m:
compiler/ml_unify_gen.m:
compiler/mlds_to_c.m:
compiler/mlds_to_gcc.m:
compiler/mlds_to_il.m:
compiler/mlds_to_java.m:
compiler/mlds_to_managed.m:
compiler/rtti_to_mlds.m:
compiler/stack_layout.m:
compiler/unify_gen.m:
	Conform to the changes above.

tests/hard_coded/lookup_switch_simple.{m,exp}:
tests/hard_coded/lookup_switch_simple_bitvec.{m,exp}:
tests/hard_coded/lookup_switch_simple_non.{m,exp}:
tests/hard_coded/lookup_switch_simple_opt.{m,exp}:
	New test cases to exercise the new functionality.

tests/hard_coded/Mmakefile:
tests/hard_coded/Mercury.options:
	Enable the new tests.
2009-09-21 04:09:06 +00:00
Peter Wang
e0ff2b1903 Implement conditional structure reuse for LLDS backends using Boehm GC.
Estimated hours taken: 15
Branches: main

Implement conditional structure reuse for LLDS backends using Boehm GC.
Verify at run time, just before reusing a dead cell, that the base address of
the cell was dynamically allocated.  If not, fall back to allocating a new
object on the heap.  This makes structure reuse safe without having to disable
static data.

In the simple case, the generated C code looks like this:

    MR_tag_reuse_or_alloc_heap(dest, tag, addr_of_reuse_cell,
	MR_tag_alloc_heap(dest, tag, count));
    ...assign fields...

If some of the fields are known to already have the correct values then we can
avoid assigning them.  We need to handle both reuse and non-reuse cases:

    MR_tag_reuse_or_alloc_heap_flag(dest, flag_reg, tag, addr_of_reuse_cell,
	MR_tag_alloc_heap(dest, tag, count));
    /* flag_reg is non-zero iff reuse is possible */
    if (flag_reg) {
	goto skip;
    }
    ...assign fields which don't need to be assigned in reuse case...
  skip:
    ...assign fields which must be assigned in both cases...

It may be that it is not worth the branch to avoid assigning known fields.
I haven't yet checked.


compiler/llds.m:
	Extend the `incr_hp' instruction to hold information for structure
	reuse.

compiler/code_info.m:
	Generate a label and pass it to `var_locn_assign_cell_to_var'.  The
	label is only needed for the type of code shown above.

compiler/var_locn.m:
	Change the code generated for cell reuse.  Rather than assigning the
	dead cell's address to the target lval unconditionally, generate an
	`incr_hp' instruction with the reuse field filled in.

	Generate code that avoids filling in known fields if possible.

	Abort if we see `construct_statically(_)' in
	`var_locn_assign_dynamic_cell_to_var'.

runtime/mercury_heap.h:
runtime/mercury_conf_param.h:
	Add a macro to check if an address is between
	`GC_least_plausible_heap_addr' and `GC_greatest_plausible_heap_addr',
	which are therefore in the heap.

	Add macros to conditionally reuse a cell or otherwise fall back to
	allocating a new object.

	Make it possible to revert to unconditional structure reuse by
	defining the C macro `MR_UNCONDITIONAL_STRUCTURE_REUSE'.

compiler/llds_out.m:
	Call the new macros in `mercury_heap.h' for `incr_hp' instructions
	with reuse information filled in.

compiler/dupelim.m:
compiler/dupproc.m:
compiler/exprn_aux.m:
compiler/global_data.m:
compiler/jumpopt.m:
compiler/livemap.m:
compiler/llds_to_x86_64.m:
compiler/middle_rec.m:
compiler/opt_debug.m:
compiler/opt_util.m:
compiler/reassign.m:
compiler/unify_gen.m:
compiler/use_local_vars.m:
	Conform to the changed `incr_hp' instruction.
2008-02-11 03:56:13 +00:00
Zoltan Somogyi
cc88711d63 Implement true multi-cons_id arm switches, i.e. switches in which we associate
Estimated hours taken: 40
Branches: main

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

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

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

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

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

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

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

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

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

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

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

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

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

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

	Replace some booleans with purpose-specific types.

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

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

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

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

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

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

	Give some predicates better names.

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

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

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

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

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

	Fix some misleading variable names.

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

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

	Rationalize the argument order of some access predicates.

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

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

	Give better names to some predicates.

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

compiler/ll_backend.m:
	Include the new module.

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

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

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

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

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

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

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

	Give some variables better names.

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

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

	Move some utility predicates to switch_util.

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

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

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

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

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

	Factor out some code to make all this possible.

	Give better names to some predicates.

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

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

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

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

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

	Give some predicates better names.

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

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

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

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

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

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

compiler/Mercury.options:
	Work around bug #32 in Mantis.
2007-12-30 08:24:23 +00:00
Zoltan Somogyi
22cead47a7 Fix bug #28 in Mantis. The only substantive change is to code_info.m; the
Estimated hours taken: 4
Branches: main

Fix bug #28 in Mantis. The only substantive change is to code_info.m; the
changes to the other compiler modules are cosmetic only.

compiler/code_info.m:
	Fix bug #28 in Mantis. The problem was with the code that generated the
	annotation giving the set of live lvalues at calls: it didn't delete
	from the set the registers used for passing dummy arguments, such as
	I/O states. A recursive call for an I/O predicate would thus compute
	the correct set of live lvalues at the start of the predicate body
	(in the case of the test case, {r1}), but the wrong set at the
	recursive call ((in the case of the test case, {r1,r2}, with r2
	being the register assigned to hold the I/O state argument). The bug
	was an abort caused by a sanity check looking for this kind of
	mismatch.

compiler/c_util.m:
	Make two predicates into functions to make them easier to use.

compiler/opt_debug.m:
	Use those functions.

compiler/ml_code_gen.m:
compiler/pragma_c_gen.m:
	Conform to the change to c_util.

compiler/jumpopt.m:
	Delete unnecessary module qualifications.

tests/valid/testxmlreader.m:
tests/valid/xmlreader.m:
	A regression test for this bug. It is in valid rather than hard_coded
	because it cannot be made executable without libraries that not all
	machines have, and which it would be inappropriate to add to the test
	suite itself.

tests/valid/Mmakefile:
	Enable the new test case.
2007-11-19 06:36:31 +00:00
Peter Wang
fa80b9a01a Make the parallel conjunction execution mechanism more efficient.
Branches: main

Make the parallel conjunction execution mechanism more efficient.

1. Don't allocate sync terms on the heap.  Sync terms are now allocated in
the stack frame of the procedure call which originates a parallel
conjunction.

2. Don't allocate individual sparks on the heap.  Sparks are now stored in
preallocated, growing arrays using an algorithm that doesn't use locks.

3. Don't have one mutex per sync term.  Just use one mutex to protect
concurrent accesses to all sync terms (it's is rarely needed anyway).  This
makes sync terms smaller and saves initialising a mutex for each parallel
conjunction encountered.

4. We don't bother to acquire the global sync term lock if we know a parallel
conjunction couldn't be executing in parallel.  In a highly parallel program,
the majority of parallel conjunctions will be executed sequentially so
protecting the sync terms from concurrent accesses is unnecessary.


par_fib(39) is ~8.4 times faster (user time) on my laptop (Linux 2.6, x86_64),
which is ~3.5 as slow as sequential execution.


configure.in:
	Update the configuration for a changed MR_SyncTerm structure.

compiler/llds.m:
	Make the fork instruction take a second argument, which is the base
	stack slot of the sync term.

	Rename it to fork_new_child to match the macro name in the runtime.

compiler/par_conj_gen.m:
	Change the generated code for parallel conjunctions to allocate sync
	terms on the stack and to pass the sync term to fork_new_child.

compiler/dupelim.m:
compiler/dupproc.m:
compiler/exprn_aux.m:
compiler/global_data.m:
compiler/jumpopt.m:
compiler/livemap.m:
compiler/llds_out.m:
compiler/llds_to_x86_64.m:
compiler/middle_rec.m:
compiler/opt_debug.m:
compiler/opt_util.m:
compiler/reassign.m:
compiler/use_local_vars.m:
	Conform to the change in the fork instruction.

compiler/liveness.m:
compiler/proc_gen.m:
	Disable use of the parallel conjunction operator in the compiler as
	older versions of the compiler will generate code incompatible with
	the new runtime.

runtime/mercury_context.c:
runtime/mercury_context.h:
	Remove the next pointer field from MR_Spark as it's no longer needed.

	Remove the mutex from MR_SyncTerm.  Add a field to record if a spark
	belonging to the sync term was scheduled globally, i.e. if the
	parallel conjunction might be executed in parallel.

	Define MR_SparkDeque and MR_SparkArray.

	Use MR_SparkDeques to hold per-context sparks and global sparks.

	Change the abstract machine instructions MR_init_sync_term,
	MR_fork_new_child, MR_join_and_continue as per the main change log.

	Use a preprocessor macro MR_LL_PARALLEL_CONJ as a shorthand for
	!MR_HIGHLEVEL_CODE && MR_THREAD_SAFE.

	Take the opportunity to clean things up a bit.

runtime/mercury_wsdeque.c:
runtime/mercury_wsdeque.h:
	New files containing an implementation of work-stealing deques.  We
	don't do work stealing yet but we use the underlying data structure.

runtime/mercury_atomic.c:
runtime/mercury_atomic.h:
	New files to contain atomic operations.  Currently it just contains
	compare-and-swap for gcc/x86_64, gcc/x86 and gcc-4.1.

runtime/Mmakefile:
	Add the new files.

runtime/mercury_engine.h:
runtime/mercury_mm_own_stacks.c:
runtime/mercury_wrapper.c:
	Conform to runtime changes.

runtime/mercury_conf_param.h:
	Update an outdated comment.
2007-10-11 11:45:22 +00:00
Julien Fischer
1fac629e6d Add support for foreign enumerations to Mercury.
Estimated hours taken: 50
Branches: main

Add support for foreign enumerations to Mercury.  These allow the
programmer to assign foreign language values as the representation of
enumeration constructors.

e.g.
	:- type status
		--->	optimal
		;	infeasible
		;	unbounded
		;	unknown.

	:- pragma foreign_enum("C", status/0, [
		optimal    - "STATUS_OPTIMAL",
		infeasible - "STATUS_INFEASIBLE",
		unbounded  - "STATUS_UNBOUNDED",
		unknown    - "STATUS_UNKNOWN"
	]).

The advantage of this is that when values of type status/0 are passed to
foreign code (C in this case) no translation is necessary.  This should
simplify the task of writing bindings to foreign language libraries.

Unification and comparison for foreign enumerations are the usual
unification and comparison for enumeration types, except that the default
ordering on them is determined by the foreign representation of the
constructors.  User-defined equality and comparison also work for foreign
enumeration types.

In order to implement foreign enumerations we have to introduce two
new type_ctor representations.  The existing ones for enum type do not
work since they use the value of an enumeration constructor to perform
table lookups in the RTTI data structures.  For foreign enumerations
we need to perform a linear search at the corresponding points.  This
means that some RTTI operations related to deconstruction are more
expensive.

The dummy type optimisation is not applied to foreign enumerations as
the code generators currently initialise the arguments of non-builtin
dummy type foreign_proc arguments to zero.  For unit foreign enumerations
they should be initialised to the correct foreign value.  (This is could be
implemented but in practice it's probably not going to be worth it.)

Currently, foreign enumerations are only supported by the C backends.

compiler/prog_io_pragma.m:
	Parse foreign_enum pragmas.

	Generalise the code used to parse association lists of sym_names
	and strings since this is now used by the code to parse foreign_enum
	pragmas as well as that for foreign_export_enum pragmas.

	Fix a typo: s/foreign_expor_enum/foreign_export_enum/

compiler/prog_item.m:
	Represent foreign_enum pragmas in the parse tree.

compiler/prog_type.m:
	Add a new type category for foreign enumerations.

compiler/modules.m:
	Add any foreign_enum pragmas for enumeration types defined in the
	interface of a module to the interface files.

	Output foreign_import_module pragmas in the interface file
	if any foreign_enum pragmas are included in it.  This ensures that
	the contents that any foreign declarations that are needed by the
	foreign_enum pragmas are visible.

compiler/make_hlds_passes.m:
compiler/add_pragma.m:
	Add pragma foreign_enum items to the HLDS after all the types
	have been added.  As they are added, error check them.

	Change the constructor tag values of foreign enum types to their
	foreign values.

compiler/module_qual.m:
	Module qualify pragma foreign_enum items.

compiler/mercury_to_mercury.m:
	Output foreign_enum pragmas.

	Generalise some of the existing code for writing out association
	lists in foreign_export_enum pragmas for use with foreign_enum
	pragmas as well.

compiler/hlds_data.m:
	Add the alternative `is_foreign_type' to the type enum_or_dummy/0.

	Add new type of cons_tag, foreign_tag, whose values are directly
	embedded in the target language.

compiler/intermod.m:
	Write out any foreign_enum pragmas for opt_exported types.
	(The XXX concerning attaching language information to foreign tags
	will be addressed in a subsequent change.)

compiler/llds.m:
compiler/mlds.m:
	Support new kinds of rval constants: llconst_foreign and
	mlconst_foreign respectively.  Both of these represent tag values
	as strings that are intended to be directly embedded in the target
	language.

compiler/llds_out.m:
	Add code to write out the new kind of rval_const.

	s/Integer/MR_Integer/ in a spot.
	s/Float/MR_Float/ in a spot.

compiler/rtti.m:
compiler/rtti_out.m:
compiler/rtti_to_mlds.m:
compiler/type_ctor_info.m:
	Add support the RTTI required by foreign enums.

compiler/switch_util.m:
	Handle switches on foreign_enums as-per normal enumerations.

compiler/table_gen.m:
	Tabling of foreign_enums is also like normal enumerations.

compiler/type_util.m:
	Add a predicate that tests whether a type is a foreign enumeration.

compiler/unify_gen.m:
compiler/unify_proc.m:
compiler/ml_unify_gen.m:
	Handle unification and comparison of foreign enumeration values.
	They are treated like normal enumerations for the purposes of
	implementing these operations.

compiler/ml_type_gen.m:
	Handle foreign enumerations when generating the MLDS representation
	of enumerations.

compiler/ml_util.m:
	Add a function to create an initializer for an object with a
	foreign tag.

compiler/mlds_to_c.m:
	Handle mlconst_foreign/1 rval constants.

compiler/bytecode_gen.m:
compiler/dupproc.m:
compiler/erl_rtti.m:
compiler/exception_analysis.m:
compiler/export.m:
compiler/exprn_aux.m:
compiler/global_data.m:
compiler/hlds_out.m:
compiler/higher_order.m:
compiler/inst_match.m:
compiler/jumpopt.m:
compiler/llds_to_x86_64.m:
compiler/ml_code_util.m:
compiler/mlds_to_gcc.m:
compiler/mlds_to_il.m:
compiler/mlds_to_java.m:
compiler/mlds_to_managed.m:
compiler/opt_debug.m:
compiler/opt_util.m:
compiler/polymorphism.m:
compiler/recompilation.version.m:
compiler/term_norm.m:
compiler/trailing_analysis.m:
	Conform to the above changes.

doc/reference_manual.texi:
	Document the new pragma.

	Fix some typos: s/pramga/pragma/, s/behavior/behaviour/

library/construct.m:
	Handle the two new type_ctor reps.

	Break an over-long line.

library/rtti_implementation.m:
	Support the two new type_ctor reps.
	(XXX The Java versions of some of this cannot be implemented until
	support for foreign enumerations is added to mlds_to_java.m.)

	Reformat the inst usereq/0 and extend it to include foreign enums.

runtime/mercury_type_info.h:
	Add two new type_ctor reps.  One for foreign enumerations and
	another for foreign enumerations with user equality.

	Define new types (and extend existing ones) in order to support
	RTTI for foreign enumerations.

runtime/mercury_unify_compare_body.h:
	Implement generic unify and compare for foreign enumerations.
	(It is the same as that for regular enumerations.)

runtime/mercury_construct.[ch]:
runtime/mercury_deconstruct.h:
	Handle (de)construction of foreign enumeration values.

runtime/mercury_deep_copy_body.h:
	Implement deep copy for foreign enumerations.

runtime/mercury_table_type_body.h:
runtime/mercury_term_size.c:
	Handle the new type_ctor representations.

java/runtime/ForeignEnumFunctorDesc.java:
	Add a Java version of the MR_ForeignEnumFuntorDesc structure.
	(Note: this is untested, as the java grade runtime doesn't work
	anyway.)

java/runtime/TypeFunctors.java:
	Add a constructor method for foreign enumerations.
	(Likewise, untested.)

NEWS:
	Announce pragma foreign_enum.

vim/syntax/mercury.vim:
	Highlight the new pragma appropriately.

tests/hard_coded/.cvsignore:
	Ignore executables generated by the new tests.

	Ignore a bunch of other files create by the Mercury compiler.

tests/hard_coded/Mmakefile:
tests/hard_coded/foreign_enum_rtti.{m,exp}:
	Test RTTI for foreign enumerations.

tests/hard_coded/foreign_enum_dummy.{m,exp}:
	Check that dummy type optimisation is disabled for foreign
	enumerations.

tests/hard_coded/Mercury.options:
tests/hard_coded/foreign_enum_mod1.{m,exp}:
tests/hard_coded/foreign_enum_mod2.m:
	Test that foreign_enum pragmas are hoisted into interface files
	and that they are handled correctly in optimization interfaces.

tests/invalid/Mercury.options:
tests/invalid/Mmakefile:
tests/invalid/foreign_enum_import.{m,err_exp}:
tests/invalid/foreign_enum_invalid.{m,err_exp}:
	Test that errors in foreign_enum pragmas are reported.

tests/tabling/Mmakefile:
tests/hard_coded/table_foreign_enum.{m,exp}:
	Test case for tabling of foreign enumerations.
2007-08-20 03:39:31 +00:00
Zoltan Somogyi
b48eaf8073 Add a first draft of the code generator support for region based memory
Estimated hours taken: 30
Branches: main

Add a first draft of the code generator support for region based memory
management. It is known to be incomplete; the missing parts are marked by XXXs.
It may also be buggy; it will be tested after Quan adds the runtime support,
i.e. the C macros invoked by the new LLDS instructions. However, the changes
in this diff shouldn't affect non-RBMM operations.

compiler/llds.m:
	Add five new LLDS instructions. Four are specific to RBMM operations.
	RBMM embeds three new stacks in compiler-reserved temp slots in
	procedure's usual Mercury stack frames, and the new LLDS instructions
	respectively

	(i)   push those stack frames onto their respective stacks,
	(ii)  fill some variable parts of those stack frames,
	(iii) fill fixed slots of those stack frames, and
	(iv)  use the contents of and/or pop those stack frames.

	(The pushing and popping affect only the new embedded stacks, not the
	usual Mercury stacks.)

	The last instruction is a new variant of the old assign instruction.
	It has identical semantics, but restricts optimization. An assign

	(a) can be deleted if its target lval is not used, and
	(b) its target lval can be changed (e.g. to a temp register) as long as
	    all the later instructions referring to that lval are changed to
	    use the new lval instead.

	Neither is permitted for the new keep_assign instruction. This is
	required because in an earlier draft we used it to assign to stack
	variables (parts of the embedded stack frames) that aren't explicitly
	referred to in later LLDS code, but are nevertheless implicitly
	referred to by some instructions (specifically iv above). We now
	use a specialized instruction (iii above) for this (since the macro
	it invokes can refer to C structure names, this makes it easier to
	keep the compiler in sync with the runtime system), but given that
	keep_assign is already implemented, may be useful later and shouldn't
	cause appreciable slowdown of the compiler, this diff keeps it.

	Extend the type that describe the contents of lvals to allow it
	to describe the new kinds of things we can now store in them.

	Add types to manage and describe the new embedded stack frames,
	and some utility functions. Change some existing utility functions
	to make all this more conceptually consistent.

compiler/ite_gen.m:
	Surround the code we generate for the condition of if-then-elses
	with the code required to ensure that regions that are logically
	removed in the condition aren't physically destroyed until we know
	that the condition succeeds (since the region may still be needed
	in the else branch), and to make sure that if the condition fails,
	all the memory allocated since the entry into the condition is
	reclaimed instantly.

compiler/disj_gen.m:
	Surround the code we generate for disjunctions with the code required
	to ensure that regions that are logically removed in a disjunct
	aren't physically destroyed if a later disjunct needs them, and to
	make sure that at entry into a non-first disjunct, all the memory
	allocated since the entry into the disjunction is reclaimed instantly.

compiler/commit_gen.m:
compiler/code_info.m:
	The protection against destruction offered by a disjunction disappears
	when a commit cuts away all later alternatives in that disjunct, so we
	must undo that protection. We therefore surround the scope of a commit
	goal with goal that achieves that objective.

	Add some new utility predicates to code_info. Remove some old utility
	functions that are now in llds.m.

compiler/continuation_info.m:
	Extend the type that describe the contents of stack slots to allow it
	to describe the new kinds of things we can now store in them.

	Rename the function symbols of that type to eliminate some ambiguities.

compiler/code_gen.m:
	Remember the set of variables live at the start of the goal
	(before the pre_goal_update updates it), since the region operations
	need to know this.

	Leave the lookup of AddTrailOps (and now AddRegionOps) to the specific
	kinds of goals that need it (the most frequent goals, unify and call,
	do not). Make both AddTrailOps and AddRegionOps use a self-explanatory
	type instead of a boolean.

compiler/lookup_switch.m:
	Conform to the change to AddTrailOps.

	Fix some misleading variable names.

compiler/options.m:
	Add some options to control the number of stack slots needed for
	various purposes. These have to correspond to the sizes of some C
	structures in the runtime system. Eventually these will be constants,
	but it is handy to keep them easily changeable while the C data
	structures are still being worked on.

	Add an option for optimizing away region ops whereever possible.
	The intention is that these should be on all the time, but we
	will want to turn them off for benchmarking.

compiler/dupelim.m:
compiler/dupproc.m:
compiler/exprn_aux.m:
compiler/frameopt.m:
compiler/global_data.m:
compiler/jumpopt.m:
compiler/livemap.m:
compiler/llds_out.m:
compiler/llds_to_x86_64.m:
compiler/middle_rec.m:
compiler/opt_debug.m:
compiler/opt_util.m:
compiler/par_conj_gen.m:
compiler/reassign.m:
compiler/stack_layout.m:
compiler/stdlabel.m:
compiler/trace_gen.m:
compiler/use_local_vars.m:
	Conform to the changes above, which mostly means handling the new
	LLDS instructions.

	In some cases, factor out existing common code, turn if-then-elses
	into switches, group common cases in switches, rationalize argument
	orders or variable names, and/or put code in execution order.

	In reassign.m, fix some old oversights that could (in some unlikely
	cases) cause bugs in the generated code.

compiler/pragma_c_gen.m:
	Exploit the capabilities of code_info.m.

compiler/prog_type.m:
	Add a utility predicate.
2007-07-31 01:56:41 +00:00
Quan Phan
d4818a3ca4 Modify the code generator so that it recognizes construct_in_region and
Estimated hours taken: 35.
Branch: main.

Modify the code generator so that it recognizes construct_in_region and
generates suitable code when RBMM is used. The main
changes are in unify_gen.m. incr_hp is also changed to receive one more
(maybe) argument for region.

compiler/unify_gen.m:
	Make it aware of HowToConstruct. This is the starting point of the
	changes in the code generator so that it can generate code which
	constructs terms in regions.

compiler/code_info.m:
compiler/var_locn.m:
        Change in accordance with the introduction of how_to_construct in
	unify_gen.m.

compiler/llds.m:
	Add one extra argument to incr_hp for the region to construct terms
	in.

compiler/dupelim.m:
compiler/dupproc.m:
compiler/exprn_aux.m:
compiler/global_data.m:
compiler/jumpopt.m:
compiler/livemap.m:
compiler/llds_to_x86_64.m:
compiler/middle_rec.m:
compiler/opt_debug.m:
compiler/opt_util.m:
compiler/par_conj_gen.m:
compiler/reassign.m:
compiler/use_local_vars.m:
	Change to deal with the extra maybe region argument in incr_hp.

compiler/llds_out.m:
	Modify so that when RBMM is used it generates suitable call to
	the region runtime for allocating terms in regions. The region
	runtime (in C code) will be posted in anothe email.

compiler/hlds_data.m:
	Fix a typo.

compiler/rbmm.interproc_region_lifetime.m:
	Change to comply with coding standard.
2007-07-09 13:28:36 +00:00
Simon Taylor
5647714667 Make all functions which create strings from characters throw an exception
Estimated hours taken: 15
Branches: main

Make all functions which create strings from characters throw an exception
or fail if the list of characters contains a null character.

This removes a potential source of security vulnerabilities where one
part of the program performs checks against the whole of a string passed
in by an attacker (processing the string as a list of characters or using
`unsafe_index' to look past the null character), but then passes the string
to another part of the program or an operating system call that only sees
up to the first null character.  Even if Mercury stored the length with
the string, allowing the creation of strings containing nulls would be a
bad idea because it would be too easy to pass a string to foreign code
without checking.

For examples see:
<http://insecure.org/news/P55-07.txt>
<http://www.securiteam.com/securitynews/5WP0B1FKKQ.html>
<http://www.securityfocus.com/archive/1/445788>
<http://www.securityfocus.com/archive/82/368750>
<http://secunia.com/advisories/16420/>

NEWS:
	Document the change.

library/string.m:
	Throw an exception if null characters are found in
	string.from_char_list and string.from_rev_char_list.

	Add string.from_char_list_semidet and string.from_rev_char_list_semidet
	which fail rather throwing an exception.  This doesn't match the
	normal naming convention, but string.from_{,rev_}char_list are widely
	used, so changing their determinism would be a bit too disruptive.

	Don't allocate an unnecessary extra word for each string created by
	from_char_list and from_rev_char_list.

	Explain that to_upper and to_lower only work on un-accented
	Latin letters.

library/lexer.m:
	Check for invalid characters when reading Mercury strings and
	quoted names.

	Improve error messages by skipping to the end of any string
	or quoted name containing an error.  Previously we just stopped
	processing at the error leaving an unmatched quote.

library/io.m:
	Make io.read_line_as_string and io.read_file_as_string return
	an error code if the input file contains a null character.

	Fix an XXX: '\0\' is not recognised as a character constant,
	but char.det_from_int can be used to make a null character.

library/char.m:
	Explain the workaround for '\0\' not being accepted as a char
	constant.

	Explain that to_upper and to_lower only work on un-accented
	Latin letters.

compiler/layout.m:
compiler/layout_out.m:
compiler/c_util.m:
compiler/stack_layout.m:
compiler/llds.m:
compiler/mlds.m:
compiler/ll_backend.*.m:
compiler/ml_backend.*.m:
	Don't pass around strings containing null characters (the string
	tables for the debugger).  This doesn't cause any problems now,
	but won't work with the accurate garbage collector.  Use lists
	of strings instead, and add the null characters when writing the
	strings out.

tests/hard_coded/null_char.{m,exp}:
	Change an existing test case to test that creation of a string
	containing a null throws an exception.

tests/hard_coded/null_char.exp2:
	Deleted because alternative output is no longer needed.

tests/invalid/Mmakefile:
tests/invalid/null_char.m:
tests/invalid/null_char.err_exp:
	Test error messages for construction of strings containing null
	characters by the lexer.

tests/invalid/unicode{1,2}.err_exp:
	Update the expected output after the change to the handling of
	invalid quoted names and strings.
2007-03-18 23:35:04 +00:00
Zoltan Somogyi
2bc37d7396 Fix a very old bug with --checked-nondet-tailcall that caused a call
Estimated hours taken: 1
Branches: main

compiler/jumpopt.m:
	Fix a very old bug with --checked-nondet-tailcall that caused a call
	instruction to not be preceded by a livevals instruction. This violated
	an invariant of the LLDS and caused livemap.m to throw an exception.

tests/hard_coded/checked_nondet_tailcall_noinline.{m,exp}:
	Add this copy of the checked_nondet_tailcall test case.

tests/hard_coded/Mercury.options:
	Compile checked_nondet_tailcall_noinline with --no-inlining, which
	used to expose the bug.

tests/hard_coded/Mmakefile:
	Enable the new test case.
2007-01-15 02:50:58 +00:00
Zoltan Somogyi
7b7dabb89a Extend this optimization to handle temporaries being both defined in
Estimated hours taken: 12
Branches: main

compiler/use_local_vars.m:
	Extend this optimization to handle temporaries being both defined in
	and used by foreign_proc_code instructions. This should eliminate
	unnecessary accesses to the MR_fake_reg array, and thus speed up
	programs that use foreign code a lot, including typeclass- and
	tabling-intensive programs, since those features are implemented using
	inline foreign code. I/O intensive should also benefit, but not much,
	since the cost of the I/O itself overwhelms the cost of the
	MR_fake_reg accesses.

	Group together the LLDS instructions that are handled similarly.
	Factor out some common code.

compiler/opt_util.m:
	Allow for the fact that foreign_proc_codes can now refer to
	temporaries.

compiler/opt_debug.m:
	Print more useful information about foreign_proc_code components.

compiler/prog_data.m:
	Rename the types and function symbols of the recently added
	foreign_proc attributes to avoid clashing with the keywords
	representing them in source code.

	Add a new foreign_proc attribute, proc_may_duplicate that governs
	whether the body of foreign code is allowed to be duplicated.

compiler/table_gen.m:
	Include does_not_affect_liveness among the annotations for the
	foreign_proc calls generated by this module. Some of these procedures
	affect memory beyond their arguments, but that memory is in tables,
	not in unlisted registers.

	Allow some of the smaller code fragments generated by this module
	to be duplicated.

compiler/inlining.m:
	Respect the may_not_duplicate foreign_proc attribute.

compiler/pragma_c_gen.m:
	Transmit any annotations about liveness from the HLDS to the LLDS,
	since without does_not_affect_liveness annotations use_local_vars.m
	cannot optimize foreign_proc_codes.

	Transmit any annotations about may_duplicate from the HLDS to the LLDS,
	since with them jumpopt can do a better job.

compiler/llds.m:
	Use the new foreign_proc attribute instead of a boolean to represent
	whether a foreign code fragment may be duplicated.

compiler/simplify.m:
	Generate an error message if a may_duplicate or may_not_duplicate
	attribute on a foreign_proc conflicts with a no_inline or inline pragma
	(respectively) on the predicate it belongs to.

compiler/hlds_pred.m:
	Fix some comment rot.

compiler/jumpopt.m:
compiler/livemap.m:
compiler/proc_gen.m:
compiler/trace_gen.m:
	Conform to the changes above.

doc/reference_manual.texi:
	Document the new foreign_proc attribute.

library/array.m:
library/builtin.m:
library/char.m:
library/dir.m:
library/float.m:
library/int.m:
library/io.m:
library/lexer.m:
library/math.m:
library/private_builtin.m:
library/string.m:
library/version_array.m:
	Add does_not_affect_liveness annotations to the C foreign_procs that
	deserve them.

configure.in:
	Require the installed compiler to support does_not_affect_liveness.

tests/invalid/test_may_duplicate.{m,err_exp}:
	Add a new test case to test the error checking code in simplify.m.

tests/invalid/Mmakefile:
	Enable the new test case.
2007-01-15 02:24:04 +00:00
Zoltan Somogyi
ba93a52fe7 This diff changes a few types from being defined as equivalent to a pair
Estimated hours taken: 10
Branches: main

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

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

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

I renamed some function symbols and predicates to avoid ambiguities.

I only made one algorithmic change (at least intentionally).
In assertion.m, comparing two goals for equality now ignores goal_infos
for all kinds of goals, whereas previously it ignored them for most kinds
of goals, but for shorthand goals it was insisting on them being equal.
This seemed to me to be a bug. Pete, can you confirm this?
2007-01-06 09:23:59 +00:00
Zoltan Somogyi
d66ed699a1 Add fields to structures representing the C code itself that says whether
Estimated hours taken: 4
Branches: main

Add fields to structures representing the C code itself that says whether
or not the C code affects the liveness of lvals. This is intended as the basis
for future improvements in the optimization of such code.

Implement a new foreign_proc attribute that allows programmers to set
the value of this field.

Eliminate names referring to `pragma c_code' in the LLDS backend in favor
of names referring to foreign_procs.

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

	Consistently put the field containing C code last in the function
	symbols that contain them.

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

	Rename some other function symbols to avoid ambiguity.

compiler/prog_io_pragma.m:
	Parse the new foreign_proc attribute.

doc/reference_manual.texi:
	Document the new attribute.

compiler/pragma_c_gen.m:
	Rename the main predicates.

compiler/opt_util.m:
	Change some predicates into functions, for more convenient invocation.

compiler/livemap.m:
	Rename the predicates in this module to avoid ambiguity and the need
	for module qualification.

compiler/*.m:
	Conform to the changes above.
2007-01-03 07:20:47 +00:00
Zoltan Somogyi
281cb97c3f Fix indentation.
Estimated hours taken: 0.1
Branches: main

compiler/jumpopt.m:
	Fix indentation.
2006-12-07 06:23:02 +00:00
Zoltan Somogyi
45fd0daf5a Implement some of Mark's wish list for making user events more useful.
Estimated hours taken: 20
Branches: main

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

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

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

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

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

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

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

	Add the new trace levels to the MR_TraceLevel type.

	Update the current layout structure version number.

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

	Give a bunch of variables better names.

	Rename a type to get rid of unnecessary underscores.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

doc/mdb_categories:
	Mention the new mdb command.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

	Fix some minor departures from our coding standards.

analysis/Mercury.options:
browser/Mercury.options:
deep_profiler/Mercury.options:
compiler/Mercury.options:
library/Mercury.options:
mdbcomp/Mercury.options:
profiler/Mercury.options:
slice/Mercury.options:
	Set --no-warn-unused-imports for those modules that are used as
	packages or otherwise break --warn-unused-imports, e.g. because they
	contain predicates with both foreign and Mercury clauses and some of
	the imports only depend on the latter.
2006-12-01 15:04:40 +00:00
Zoltan Somogyi
ecf1ee3117 Add a mechanism for growing the stacks on demand by adding new segments
Estimated hours taken: 20
Branches: main

Add a mechanism for growing the stacks on demand by adding new segments
to them. You can ask for the new mechanism via a new grade component, stseg
(short for "stack segments").

The mechanism works by adding a test to each increment of a stack pointer (sp
or maxfr). If the test indicates that we are about to run out of stack, we
allocate a new stack segment, allocate a placeholder frame on the new segment,
and then allocate the frame we wanted in the first place on top of the
placeholder. We also override succip to make it point code that will (1)
release the new segment when the newly created stack frame returns, and then
(2) go to the place indicated by the original, overridden succip.

For leaf procedures on the det stack, we optimize away the check of the stack
pointer. We can do this because we reserve some space on each stack for the
use of such stack frames.

My intention is that doc/user_guide.texi and NEWS will be updated once we have
used the feature ourselves for a while and it seems to be stable.

runtime/mercury_grade.h:
	Add the new grade component.

runtime/mercury_conf_param.h:
	Document the new grade component, and the option used to debug stack
	segments.

runtime/mercury_context.[ch]:
	Add new fields to contexts to hold the list of previous segments of the
	det and nondet stacks.

runtime/mercury_memory_zones.[ch]:
	Include a threshold in all zones, for use in stack segments.
	Set it when a zone is allocated.

	Restore the previous #ifdef'd out function MR_unget_zone, for use
	when freeing stack segments execution has fallen out of.

runtime/mercury_debug.[ch]:
	When printing the offsets of pointers into the det and nondet stacks,
	print the number of the segment the pointer points into (unless it is
	the first, in which case we suppress this in the interest of brevity
	and simplicity).

	Make all the functions in this module take a FILE * as an input
	argument; don't print to stdout by default.

runtime/mercury_stacks.[ch]:
	Modify the macros that allocate stack frames to invoke the code for
	adding new stack segments when we are about to run out of stack.

	Standardize on "nondet" over "nond" as the abbreviation referring to
	the nondet stack.

	Conform to the changes in mercury_debug.c.

runtime/mercury_stack_trace.c:
	When traversing the stack, step over the placeholder stack frames
	at the bottoms of stack segments.

	Conform to the changes in mercury_debug.c.

runtime/mercury_wrapper.[ch]:
	Make the default stack size small in grades that support stack
	segments.

	Standardize on "nondet" over "nond" as the abbreviation referring to
	the nondet stack.

	Conform to the changes in mercury_debug.c.

runtime/mercury_memory.c:
	Standardize on "nondet" over "nond" as the abbreviation referring to
	the nondet stack.

runtime/mercury_engine.[ch]:
runtime/mercury_overflow.h:
	Standardize on "nondet" over "nond" as the abbreviation referring to
	the nondet stack.

	Convert these files to four-space indentation.

runtime/mercury_minimal_model.c:
trace/mercury_trace.c:
trace/mercury_trace_util.c:
	Conform to the changes in mercury_debug.c.

compiler/options.m:
	Add the new grade option for stack segments.

compiler/compile_target_code.m:
compiler/handle_options.m:
	Add the new grade component, and handle its exclusions with other grade
	components and optimizations.

compiler/llds.m:
	Extend the incr_sp instruction to record whether the stack frame
	is for a leaf procedure.

compiler/llds_out.m:
	Output the extended incr_sp instruction.

compiler/proc_gen.m:
	Fill in the extra slot in incr_sp instructions.

compiler/goal_util.m:
	Provide a predicate for testing whether a procedure body is a leaf.

compiler/delay_slot.m:
compiler/dupelim.m:
compiler/dupproc.m:
compiler/exprn_aux.m:
compiler/frameopt.m:
compiler/global_data.m:
compiler/jumpopt.m:
compiler/middle_rec.m:
compiler/opt_debug.m:
compiler/opt_util.m:
compiler/peephole.m:
compiler/reassign.m:
compiler/use_local_vars.m:
	Conform to the change in llds.m.

scripts/canonicate_grade.sh-subr:
scripts/init_grade_options.sh-subr:
scripts/parse_grade_options.sh-subr:
scripts/final_grade_options.sh-subr:
scripts/mgnuc.in:
	Handle the new grade component.

	Convert parse_grade_options.sh-subr to four-space indentation.

Mmake.workspace:
	Fix an old bug that prevented bootcheck from working in the new grade:
	when computing the gc grade, use the workspace's version of ml (which
	in this case understands the new grade components), rather than the
	installed ml (which does not).

	(This was a devil to track down, because neither make --debug nor
	strace on make revealed how the installed ml was being invoked,
	and there was no explicit invocation in the Makefile either; the error
	message appeared to come out of thin air just before the completion
	of the stage 2 library. It turned out the invocation happened
	implicitly, as a result of expanding a make variable.)
2006-11-01 02:31:19 +00:00
Zoltan Somogyi
e21193c283 Rename a bunch of predicates and function symbols to eliminate
Estimated hours taken: 6
Branches: main

browser/*.m:
compiler/*.m:
	Rename a bunch of predicates and function symbols to eliminate
	ambiguities.

	The only real change is factoring out some common code in the mlds
	and llds code generators, replacing them with single definitions
	in switch_util.m.
2006-10-15 23:26:56 +00:00
Peter Wang
712027f307 This patch changes the parallel execution mechanism in the low level backend.
Estimated hours taken: 100
Branches: main

This patch changes the parallel execution mechanism in the low level backend.
The main idea is that, even in programs with only moderate parallelism, we
won't have enough processors to exploit it all.  We should try to reduce the
cost in the common case, i.e. when a parallel conjunction gets executed
sequentially.  This patch does two things along those lines:

(1) Instead of unconditionally executing all parallel conjuncts (but the last)
in separate Mercury contexts, we allow a context to continue execution of the
next conjunct of a parallel conjunction if it has just finished executing the
previous conjunct.  This saves on allocating unnecessary contexts, which can
be a big reduction in memory usage.

We also try to execute conjuncts left-to-right so as to minimise the
need to suspend contexts when there are dependencies between conjuncts.

(2) Conjuncts that *are* executed in parallel still need separate contexts.
We used to pass variable bindings to those conjuncts by flushing input
variable values to stack slots and copying the procedure's stack frame to the
new context.  When the conjunct finished, we would copy new variable bindings
back to stack slots in the original context.

What happens now is that we don't do any copying back and forth.  We introduce
a new abstract machine register `parent_sp' which points to the location of
the stack pointer at the time that a parallel conjunction began.  In parallel
conjuncts we refer to all stack slots via the `parent_sp' pointer, since we
could be running on a different context altogether and `sp' would be pointing
into a new detstack.  Since parallel conjuncts now share the procedure's stack
frame, we have to allocate stack slots such that all parallel conjuncts in a
procedure that could be executing simultaneously have distinct sets of stack
slots.  We currently use the simplest possible strategy, i.e. don't allow
variables in parallel conjuncts to reuse stack slots.

Note: in effect parent_sp is a frame pointer which is only set for and used by
the code of parallel conjuncts.  We don't call it a frame pointer as it can be
confused with "frame variables" which have to do with the nondet stack.


compiler/code_info.m:
	Add functionality to keep track of how deep inside of nested parallel
	conjunctions the code generator is.

	Add functionality to acquire and release "persistent" temporary stack
	slots.  Unlike normal temporary stack slots, these don't get implicitly
	released when the code generator's location-dependent state is reset.

	Conform to additions of `parent_sp' and parent stack variables.

compiler/exprn_aux.m:
	Generalise the `substitute_lval_in_*' predicates by
	`transform_lval_in_*' predicates.  Instead of performing a fixed
	substitution, these take a higher order predicate which performs some
	operation on each lval.  Redefine the substitution predicates in terms
	of the transformation predicates.

	Conform to changes in `fork', `join_and_terminate' and
	`join_and_continue' instructions.

	Conform to additions of `parent_sp' and parent stack variables.

	Remove `substitute_rval_in_args' and `substitute_rval_in_arg' which
	were unused.

compiler/live_vars.m:
	Introduce a new type `parallel_stackvars' which is threaded through
	`build_live_sets_in_goal'.  We accumulate the sets of variables which
	are assigned stack slots in each parallel conjunct.  At the end of
	processing a parallel conjunction, use this information to force
	variables which are assigned stack slots to have distinct slots.

compiler/llds.m:
	Change the semantics of the `fork' instruction.  It now takes a single
	argument: the label of the next conjunct after the current one.  The
	instruction now "sparks" the next conjunct to be run, either in a
	different context (possibly in parallel, on another Mercury engine) or
	is queued to be executed in the current context after the current
	conjunct is finished.

	Change the semantics of the `join_and_continue' instruction.  This
	instruction now serves to end all parallel conjuncts, not just the
	last one in a parallel conjunction.

	Remove the `join_and_terminate' instruction (no longer used).

	Add the new abstract machine register `parent_sp'.

	Introduce "parent stack slots", which are similar to normal stack
	slots but relative to the `parent_sp' register.

compiler/par_conj_gen.m:
	Change the code generated for parallel conjunctions.  That is:

	- use the new `fork' instruction at the beginning of a parallel
	  conjunct;

	- use the `join_and_continue' instruction at the end of all parallel
	  conjuncts;

	- keep track of how deep the code generator currently is in parallel
	  conjunctions;

	- set and restore the `parent_sp' register when entering a non-nested
	  parallel conjunction;

	- after generating the code of a parallel conjunct, replace all
	  references to stack slots by parent stack slots;

	- remove code to copy back output variables when a parallel conjunct
	  finishes.

	Update some comments.

runtime/mercury_context.c:
runtime/mercury_context.h:
	Add the type `MR_Spark'.  Sparks are allocated on the heap and contain
	enough information to begin execution of a single parallel conjunct.

	Add globals `MR_spark_queue_head' and `MR_spark_queue_tail'.  These
	are pointers to the start and end of a global queue of sparks.  Idle
	engines can pick up work from this queue in the same way that they can
	pick up work from the global context queue (the "run queue").

	Add new fields to the MR_Context structure.  `MR_ctxt_parent_sp' is a
	saved copy of the `parent_sp' register for when the context is
	suspended.  `MR_ctxt_spark_stack' is a stack of sparks that we decided
	not to put on the global spark queue.

	Update `MR_load_context' and `MR_save_context' to save and restore
	`MR_ctxt_parent_sp'.

	Add the counters `MR_num_idle_engines' and
	`MR_num_outstanding_contexts_and_sparks'.  These are used to decide,
	when a `fork' instruction is reached, whether a spark should be put on
	the global spark queue (with potential for parallelism but also more
	overhead) or on the calling context's spark stack (no parallelism and
	less overhead).

	Rename `MR_init_context' to `MR_init_context_maybe_generator'.  When
	initialising contexts, don't reset redzones of already allocated
	stacks.  It seems to be unnecessary (and the reset implementation is
	buggy anyway, though it's fine on Linux).

	Rename `MR_schedule' to `MR_schedule_context'.  Add new functions
	`MR_schedule_spark_globally' and `MR_schedule_spark_locally'.

	In `MR_do_runnext', add code for idle engines to get work from the
	global spark queue.  Resuming contexts are prioritised over sparks.

	Rename `MR_fork_new_context' to `MR_fork_new_child'.  Change the
	definitions of `MR_fork_new_child' and `MR_join_and_continue' as per
	the new behaviour of the `fork' and `join_and_continue' instructions.
	Delete `MR_join_and_terminate'.

	Add a new field `MR_st_orig_context' to the MR_SyncTerm structure to
	record which context originated the parallel conjunction instance
	represented by a MR_SyncTerm instance, and update `MR_init_sync_term'.
	This is needed by the new behaviour of `MR_join_and_continue'.

	Update some comments.

runtime/mercury_engine.h:
runtime/mercury_regs.c:
runtime/mercury_regs.h:
runtime/mercury_stacks.h:
	Add the abstract machine register `parent_sp' and code to copy it to
	and from the fake_reg array.

	Add a macro `MR_parent_sv' to access stack slots via `parent_sp'.

	Add `MR_eng_parent_sp' to the MercuryEngine structure.

runtime/mercury_wrapper.c:
runtime/mercury_wrapper.h:
	Add Mercury runtime option `--max-contexts-per-thread' which is saved
	in the global variable `MR_max_contexts_per_thread'.  The number
	`MR_max_outstanding_contexts' is derived from this.  It sets a soft
	limit on the number of sparks we put in the global spark queue,
	relative to the number of threads we are running.  We don't want to
	put too many sparks on the global queue if there are plenty of ready
	contexts or sparks already on the global queues, as they are likely to
	result in new contexts being allocated.

	When initially creating worker engines, wait until all the worker
	engines have acknowledged that they are idle before continuing.  This
	is mainly so programs (especially benchmarks and test cases) with only
	a few fork instructions near the beginning of the program don't
	execute the forks before any worker engines are ready, resulting in no
	parallelism.

runtime/mercury_engine.c:
runtime/mercury_thread.c:
	Don't allocate a context at the time a Mercury engine is created.  An
	engine only needs a new context when it is about to pick up a spark.

configure.in:
compiler/options.m:
scripts/Mercury.config.in:
	Update to reflect the extra field in MR_SyncTerm.

	Add the option `--sync-term-size' and actually make use the result of
	the sync term size calculated during configuration.

compiler/code_util.m:
compiler/continuation_info.m:
compiler/dupelim.m:
compiler/dupproc.m:
compiler/global_data.m:
compiler/hlds_llds.m:
compiler/jumpopt.m:
compiler/livemap.m:
compiler/llds_out.m:
compiler/middle_rec.m:
compiler/opt_debug.m:
compiler/opt_util.m:
compiler/reassign.m:
compiler/stack_layout.m:
compiler/use_local_vars.m:
compiler/var_locn.m:
	Conform to changes in `fork', `join_and_terminate' and
	`join_and_continue' instructions.

	Conform to additions of `parent_sp' and parent stack variables.

	XXX not sure about the changes in stack_layout.m

library/par_builtin.m:
	Conform to changes in the runtime system.
2006-09-26 03:53:23 +00:00
Zoltan Somogyi
00741b0162 This diff contains no algorithmic changes.
Estimated hours taken: 6
Branches: main

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

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

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

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

tests/debugger/declarative/dependency.exp:
tests/debugger/declarative/dependency2.exp:
	Update the expected out where some internal function symbol names
	appear in the output of the debugger. (This output is meant for
	implementors only.)
2006-08-22 05:04:29 +00:00
Zoltan Somogyi
4924dfb1c9 One of Hans Boehm's papers says that heap cells allocated by GC_MALLOC_ATOMIC
Estimated hours taken: 5
Branches: main

One of Hans Boehm's papers says that heap cells allocated by GC_MALLOC_ATOMIC
are grouped together into pages, and these pages aren't scanned during the
sweep phase of the garbage collector. I therefore modified the compiler
to use GC_MALLOC_ATOMIC instead of GC_MALLOC whereever possible, i.e
when the cell being allocated is guaranteed not to have any pointer to
GCable memory inside it.

My first benchmarking run showed a speedup of 4.5% in asm_fast.gc:

EXTRA_MCFLAGS = --use-atomic-cells
mercury_compile.01 average of 6 with ignore=1     18.30
EXTRA_MCFLAGS = --no-use-atomic-cells
mercury_compile.02 average of 6 with ignore=1     19.17

However, later benchmarks, after the upgrade to version 7.0 of boehm_gc,
show a less favourable and more mixed picture, with e.g. a 4% speedup
in hlc.gc at -O3, a 3% slowdown in asm_fast.gc at -O4, and little effect
otherwise:

EXTRA_MCFLAGS = -O1 --use-atomic-cells
GRADE = asm_fast.gc
mercury_compile.01 average of 6 with ignore=1     23.30
EXTRA_MCFLAGS = -O1 --no-use-atomic-cells
GRADE = asm_fast.gc
mercury_compile.02 average of 6 with ignore=1     23.28

EXTRA_MCFLAGS = -O2 --use-atomic-cells
GRADE = asm_fast.gc
mercury_compile.03 average of 6 with ignore=1     18.51
EXTRA_MCFLAGS = -O2 --no-use-atomic-cells
GRADE = asm_fast.gc
mercury_compile.04 average of 6 with ignore=1     18.66

EXTRA_MCFLAGS = -O3 --use-atomic-cells
GRADE = asm_fast.gc
mercury_compile.05 average of 6 with ignore=1     18.44
EXTRA_MCFLAGS = -O3 --no-use-atomic-cells
GRADE = asm_fast.gc
mercury_compile.06 average of 6 with ignore=1     18.48

EXTRA_MCFLAGS = -O4 --use-atomic-cells
GRADE = asm_fast.gc
mercury_compile.07 average of 6 with ignore=1     18.28
EXTRA_MCFLAGS = -O4 --no-use-atomic-cells
GRADE = asm_fast.gc
mercury_compile.08 average of 6 with ignore=1     17.70

EXTRA_MCFLAGS = -O1 --use-atomic-cells
GRADE = hlc.gc
mercury_compile.09 average of 6 with ignore=1     24.78
EXTRA_MCFLAGS = -O1 --no-use-atomic-cells
GRADE = hlc.gc
mercury_compile.10 average of 6 with ignore=1     24.69

EXTRA_MCFLAGS = -O2 --use-atomic-cells
GRADE = hlc.gc
mercury_compile.11 average of 6 with ignore=1     19.36
EXTRA_MCFLAGS = -O2 --no-use-atomic-cells
GRADE = hlc.gc
mercury_compile.12 average of 6 with ignore=1     19.26

EXTRA_MCFLAGS = -O3 --use-atomic-cells
GRADE = hlc.gc
mercury_compile.13 average of 6 with ignore=1     18.64
EXTRA_MCFLAGS = -O3 --no-use-atomic-cells
GRADE = hlc.gc
mercury_compile.14 average of 6 with ignore=1     19.38

EXTRA_MCFLAGS = -O4 --use-atomic-cells
GRADE = hlc.gc
mercury_compile.15 average of 6 with ignore=1     19.39
EXTRA_MCFLAGS = -O4 --no-use-atomic-cells
GRADE = hlc.gc
mercury_compile.16 average of 6 with ignore=1     19.41

runtime/mercury_heap.h:
	Define atomic equivalents of the few heap allocation macros
	that didn't already have one. These macros are used by the LLDS
	backend.

runtime/mercury.h:
	Define an atomic equivalent of the MR_new_object macro.
	These macros are used by the MLDS backend.

	Use MR_new_object_atomic instead of MR_new_object to box floats.

compiler/hlds_data.m:
compiler/llds.m:
compiler/mlds.m:
	Modify the representations of the heap allocations constructs
	to include a flag that says whether we should use the atomic variants
	of the heap allocation macros.

compiler/llds_out.m:
compiler/mlds_to_c.m:
	Respect this extract flag when emitting C code.

	In mlds_to_c.m, also add some white space that makes the code easier
	for humans to read.

compiler/type_util.m:
	Add a mechanism for finding out whether we can put a value of a given
	type into an atomic cell.

	Put the definitions of functions and predicates in this module
	in the same order as their declarations.

	Turn some predicates into functions. Change the argument order of
	some predicates to conform to our usual conventions.

compiler/unify_gen.m:
compiler/ml_unify_gen.m:
	Use the new mechanism in type_util.m to generate code that creates
	atomic heap cells if this is possible and is requested.

compiler/code_info.m:
compiler/var_locn.m:
	Act on the information provided by unify_gen.m.

compiler/options.m:
doc/user_guide.texi:
	Add an option to control whether the compiler should try to use
	atomic cells.

compiler/dupelim.m:
compiler/dupproc.m:
compiler/exprn_aux.m:
compiler/higher_order.m:
compiler/jumpopt.m:
compiler/livemap.m:
compiler/middle_rec.m:
compiler/ml_code_util.m:
compiler/ml_elim_nested.m:
compiler/ml_optimize.m:
compiler/ml_util.m:
compiler/mlds_to_gcc.m:
compiler/mlds_to_il.m:
compiler/mlds_to_java.m:
compiler/modecheck_unify.m:
compiler/opt_debug.m:
compiler/opt_util.m:
compiler/par_conj_gen.m:
compiler/polymorphism.m:
compiler/reassign.m:
compiler/size_prof.m:
compiler/structure_sharing.domain.m:
compiler/use_local_vars.m:
	Minor diffs to conform to the changes above.

compiler/structure_reuse.direct.choose_reuse.m:
	Add an XXX comment about the interaction of the new capability
	with structure reuse.
2006-08-20 05:01:48 +00:00
Zoltan Somogyi
469f1dc09b This diff contains no algorithmic changes.
Estimated hours taken: 1.5
Branches: main

This diff contains no algorithmic changes.

compiler/llds.m:
compiler/mlds.m:
	Rename some function symbols and field names to avoid ambiguities
	with respect to language keywords.

compiler/*.m:
	Conform to the changes in llds.m and mlds.m.
2006-07-28 05:08:15 +00:00