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24 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
Zoltan Somogyi
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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? |
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Julien Fischer
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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. |
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Julien Fischer
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aeeedd2c13 |
Standardize formatting of comments at the beginning of modules.
compiler/*.m: Standardize formatting of comments at the beginning of modules. |
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Zoltan Somogyi
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9d23d8e2e7 |
Implement the trace goal construct we discussed, for now for the LLDS backends
Estimated hours taken: 70
Branches: main
Implement the trace goal construct we discussed, for now for the LLDS backends
only.
Since the syntax of trace goals is non-trivial, useful feedback on syntax
errors inside trace goal attributes is essential. With the previous setup, this
wasn't possible, since the code that turned terms into parse tree goals turned
*all* terms into goals; it couldn't recognize any errors, sweeping them under
the rug as calls. This diff changes that. Now, if this code recognizes a
keyword that indicates a particular construct, it insists on the rest of the
code following the syntax required for that construct, and returns error
messages if it doesn't.
We handle the trace goal attributes that specify state variables to be threaded
through the trace goal (either the I/O state or a mutable variable) in
add_clause.m, at the point at which we transform the list of items to the HLDS.
We handle the compile-time condition on trace goals in the invocation of
simplify at the end of semantics analysis, by eliminating the goal if the
compile-time condition isn't met. We handle run-time conditions on trace goals
partially in the same invocation of simplify: we transform trace goals with
runtime conditions into an if-then-else with the trace goal as the then part
and `true' as the else part, the condition being a foreign_proc that is handled
specially by the code generator, that special handling being to replace
the actual code of the foreign_proc (which is a dummy) with the evaluation of
the runtime condition.
Since these changes require significant changes to some of our key data
structures, I took the liberty of doing some renaming of function symbols
at the same time to avoid using ambiguities with respect to language keywords.
library/ops.m:
Add "trace" as an operator.
compiler/prog_data.m:
Define data types to represent the various attributes of trace goals.
Rename some function symbols to avoid ambiguities.
compiler/prog_item.m:
Extend the parse tree representation of goals with a trace goal.
compiler/mercury_to_mercury.m:
Output the new kind of goal and its components.
compiler/hlds_goal.m:
Extend the HLDS representation of scopes with a scope_reason
representing trace goals.
Add a mechanism (an extra argument in foreign_procs) to allow
the representation of goals that evaluate runtime trace conditions.
Since this requires modifying all code that traverses the HLDS,
do some renames that were long overdue: rename not as negation,
rename call as plain_call, and rename foreign_proc as
call_foreign_proc. These renames all avoid using language keywords
as function symbols.
Change the way we record goals' purities. Instead of optional features
to indicate impure or semipure, which is error-prone, use a plain
field in the goal_info, accessed in the usual way.
Add a way to represent that a goal contains a trace goal, and should
therefore be treated as if it were impure when considering whether to
optimize it away.
Reformat some comments describing function symbols.
compiler/hlds_out.m:
Output the new construct in the HLDS.
compiler/prog_io_util.m:
Generalize the maybe[123] types to allow the representation of more
than one error message. Add functions to extract the error messages.
Add a maybe4 type. Rename the function symbols of these types to
avoid massive ambiguity.
Change the order of some predicates to bring related predicates
next to each other.
compiler/prog_io.m:
compiler/prog_io_dcg.m:
compiler/prog_io_goal.m:
compiler/prog_io_pragma.m:
Rework these modules almost completely to find and accumulate syntax
errors as terms are being parsed. In some cases, this allowed us to
replace "XXX this is a hack" markers with meaningful error-reporting
code.
In prog_io_goal.m, add code for parsing trace goals.
In a bunch of places, update obsolete coding practices, such as using
nested chains of closures instead of simple sequential code, and
using A0 and A to refer to values of different types (terms and goals
respectively). Use more meaningful variable names.
Break up some too-large predicates.
compiler/superhomogeneous.m:
Find and accumulate syntax errors as terms are being parsed.
compiler/add_clause.m:
Add code to transform trace goals from the parse tree to the HLDS.
This is where the IO state and mutable variable attributes of trace
goals are handled.
Eliminate the practice of using the naming scheme Body0 and Body
to refer to values of different types (prog_item.goal and hlds_goal
respectively).
Use error_util for some error messages.
library/private_builtin.m:
Add the predicates referred to by the transformation in add_clause.m.
compiler/goal_util.m:
Rename a predicate to avoid ambiguity.
compiler/typecheck.m:
Do not print error messages about missing clauses if some errors have
been detected previously.
compiler/purity.m:
Instead of just computing purity, compute (and record) also whether
a goal contains a trace goal. However, treat trace goals as pure.
compiler/mode_info.m:
Add trace goals as a reason for locking variables.
Rename some function symbols to avoid ambiguity.
compiler/modes.m:
When analyzing trace goal scopes, lock the scope's nonlocal variables
to prevent them from being further instantiated.
compiler/det_analysis.m:
Insist on the code in trace goal scopes being det or cc_multi.
compiler/det_report.m:
Generate the error message if the code in a trace goal scope isn't det
or cc_multi.
compiler/simplify.m:
At the end of the front end, eliminate trace goal scopes if their
compile-time condition is false. Transform trace goals with runtime
conditions as described at the top.
Treat goals that contain trace goals as if they were impure when
considering whether to optimize them away.
compiler/mercury_compile.m:
Tell simplify when it is being invoked at the end of the front end.
Rename a predicate to avoid ambiguity.
compiler/trace_params.m:
Provide the predicates simplify.m need to be able to evaluate the trace
goal conditions regarding trace levels.
compiler/trace.m:
compiler/trace_gen.m:
Rename the trace module as trace_gen, since "trace" is now an operator.
Rename some predicates exported by the module, now that it is no longer
possible to preface calls with "trace." as a module qualifier.
compiler/notes/compiler_design.html:
Document this name change.
compiler/options.m:
Rename the trace option as trace_level internally, since "trace"
is now an operator. The user-visible name remains the same.
Add the new --trace-flag option.
Delete an obsolete option.
compiler/handle_options.m:
Rename the function symbols of the grade_component type,
since "trace" is now an operator.
compiler/llds.m:
Extend the LLDS with a mechanism to refer to C global variables.
For now, these are used to refer to C globals that will be created
by mkinit to represent the initial values of the environment variables
referred to by trace goals.
compiler/commit_gen.m:
Check that no trace goal with a runtime condition survives to code
generation; they should have been transformed by simplify.m.
compiler/code_gen.m:
Tell commit_gen.m what kind of scope it is generating code for.
compiler/pragma_c_gen.m:
Generate code for runtime conditions when handling the foreign_procs
created by simplify.m.
compiler/code_info.m:
Allow pragma_c_gen.m to record what environment variables it has
generated references to.
compiler/proc_gen.m:
Record the set of environment variables a procedure refers to
in the LLDS procedure header, for efficient access by llds_out.m.
compiler/llds_out.m:
Handle the new LLDS construct, and tell mkinit which environment
variables need C globals created for them.
compiler/pd_util.m:
Rename some predicates to avoid ambiguity.
compiler/*.m:
Conform to the changes above, mainly the renames of function symbols
and predicates, the changed signatures of some predicates, and the new
handling of purity.
util/mkinit.c:
Generate the definitions and the initializations of any C globals
representing the initial status (set or not set) of environment
variables needed by trace goals.
library/assoc_list.m:
Add some predicates that are useful in prog_io*.m.
library/term_io.m:
Minor cleanup.
tests/hard_coded/trace_goal_{1,2}.{m,exp}:
New test cases to test the new construct, identical except for whether
the trace goal is enabled at compile time.
tests/hard_coded/trace_goal_env_{1,2}.{m,exp}:
New test cases to test the new construct, identical except for whether
the trace goal is enabled at run time.
tests/hard_coded/Mercury.options:
tests/hard_coded/Mmakefile:
Enable the new test cases.
tests/invalid/*.err_exp:
Update the expected output for the new versions of the error messages
now being generated.
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Julien Fischer
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459847a064 |
Move the univ, maybe, pair and unit types from std_util into their own
Estimated hours taken: 18 Branches: main Move the univ, maybe, pair and unit types from std_util into their own modules. std_util still contains the general purpose higher-order programming constructs. library/std_util.m: Move univ, maybe, pair and unit (plus any other related types and procedures) into their own modules. library/maybe.m: New module. This contains the maybe and maybe_error types and the associated procedures. library/pair.m: New module. This contains the pair type and associated procedures. library/unit.m: New module. This contains the types unit/0 and unit/1. library/univ.m: New module. This contains the univ type and associated procedures. library/library.m: Add the new modules. library/private_builtin.m: Update the declaration of the type_ctor_info struct for univ. runtime/mercury.h: Update the declaration for the type_ctor_info struct for univ. runtime/mercury_mcpp.h: runtime/mercury_hlc_types.h: Update the definition of MR_Univ. runtime/mercury_init.h: Fix a comment: ML_type_name is now exported from type_desc.m. compiler/mlds_to_il.m: Update the the name of the module that defines univs (which are handled specially by the il code generator.) library/*.m: compiler/*.m: browser/*.m: mdbcomp/*.m: profiler/*.m: deep_profiler/*.m: Conform to the above changes. Import the new modules where they are needed; don't import std_util where it isn't needed. Fix formatting in lots of modules. Delete duplicate module imports. tests/*: Update the test suite to confrom to the above changes. |
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Zoltan Somogyi
|
12deb40264 |
Rename all the get access predicates in these modules that don't
Estimated hours taken: 0.1 Branches: main compiler/hlds_clauses.m: compiler/hlds_pred.m: Rename all the get access predicates in these modules that don't already have put "get" in their name. (The names of the set access predicates were OK already.) compiler/*.m: Conform to the above. All this was done by this sed script: s/clauses_info_varset/clauses_info_get_varset/ s/clauses_info_explicit_vartypes/clauses_info_get_explicit_vartypes/ s/clauses_info_vartypes/clauses_info_get_vartypes/ s/clauses_info_headvars/clauses_info_get_headvars/ s/clauses_info_clauses_rep/clauses_info_get_clauses_rep/ s/clauses_info_rtti_varmaps/clauses_info_get_rtti_varmaps/ s/pred_info_import_status/pred_info_get_import_status/ s/pred_info_arg_types/pred_info_get_arg_types/ s/pred_info_typevarset/pred_info_get_typevarset/ s/pred_info_tvar_kinds/pred_info_get_tvar_kinds/ s/pred_info_procedures/pred_info_get_procedures/ s/proc_info_context/proc_info_get_context/ s/proc_info_varset/proc_info_get_varset/ s/proc_info_vartypes/proc_info_get_vartypes/ s/proc_info_headvars/proc_info_get_headvars/ s/proc_info_inst_varset/proc_info_get_inst_varset/ s/proc_info_maybe_declared_argmodes/proc_info_get_maybe_declared_argmodes/ s/proc_info_argmodes/proc_info_get_argmodes/ s/proc_info_maybe_arglives/proc_info_get_maybe_arglives/ s/proc_info_declared_determinism/proc_info_get_declared_determinism/ s/proc_info_inferred_determinism/proc_info_get_inferred_determinism/ s/proc_info_goal/proc_info_get_goal/ s/proc_info_can_process/proc_info_get_can_process/ s/proc_info_rtti_varmaps/proc_info_get_rtti_varmaps/ s/proc_info_eval_method/proc_info_get_eval_method/ s/proc_info_is_address_taken/proc_info_get_is_address_taken/ s/proc_info_stack_slots/proc_info_get_stack_slots/ s/proc_info_liveness_info/proc_info_get_liveness_info/ s/proc_info_context/proc_info_get_context/ s/proc_info_context/proc_info_get_context/ s/proc_info_context/proc_info_get_context/ s/proc_info_context/proc_info_get_context/ s/proc_info_context/proc_info_get_context/ s/proc_info_context/proc_info_get_context/ s/proc_info_context/proc_info_get_context/ |
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Zoltan Somogyi
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3ebda6545f |
Move the stuff currently in hlds_pred.m that deals with clauses into a new
Estimated hours taken: 1.5 Branches: main Move the stuff currently in hlds_pred.m that deals with clauses into a new module, hlds_clauses.m. Move the stuff currently in hlds_pred.m that deals with RTTI into a new module, hlds_rtti.m. Move the stuff currently in hlds_module.m that deals with predicate tables into a new module, pred_table.m. These changes make hlds_pred.m and hlds_module.m much more cohesive, but there are no changes in algorithms. compiler/hlds_clauses.m: compiler/hlds_rtti.m: compiler/pred_table.m: New modules as described above. In some cases, fix mixleading or ambiguous predicate names in the process, and convert a few predicates to functions. compiler/hlds_pred.m: compiler/hlds_module.m: Delete the stuff moved to other modules. compiler/*.m: In modules that need the functionality moved a new module, import the new module. It is rare for all the new modules to be needed, and many modules don't need any of the new modules at all. (For example, of the 200+ modules that import hlds_module.m, only about 40 need pred_table.m.) Conform to the few minor changes to e.g. predicate names. compiler/notes/compiler_design.html: Document the new modules. |
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Zoltan Somogyi
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be5b71861b |
Convert almost all the compiler modules to use . instead of __ as
Estimated hours taken: 6 Branches: main compiler/*.m: Convert almost all the compiler modules to use . instead of __ as the module qualifier. In some cases, change the names of predicates and types to make them meaningful without the module qualifier. In particular, most of the types that used to be referred to with an "mlds__" prefix have been changed to have a "mlds_" prefix instead of changing the prefix to "mlds.". There are no algorithmic changes. |
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Zoltan Somogyi
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5b8f96f61d |
Prepare for an extension of promise_equivalent_solutions that will allow us
Estimated hours taken: 5 Branches: main Prepare for an extension of promise_equivalent_solutions that will allow us to better handle values of user-defined types. The problem is that currently, the deconstruction of a value of such a type can be followed only by code that cannot fail, otherwise the cc_multi deconstruction is not in the required single-solution context. If the following code is naturally semidet, this can be worked around by turning it into det code returning a maybe and testing the maybe outside the promise_equivalent_solutions, but this is inefficient, and in any case it does not generalize to nondet code without even more horrendous inefficiency and inconvenience. (You have to create a nondet closure and call it outside the promise_equivalent_solutions.) The solution I came up with is something is to have a construct that contains - a list of deconstructions on types with user-defined equality, - a goal, and - the list of outputs of that goal. The idea is that this would be transformed into a conjunction of the first and second items, and wrapped inside a special kind of conj that provides a scope for the implicit promise, which is that the set of solutions of the goal in the second item doesn't depend on what concrete terms the deconstructions in the first item return out of the set of concrete terms they *could* return. The deconstructions in the first item would be marked to tell determinism analysis to effectively ignore the fact that they involve user-defined equality. The actual addition of that construct is left for a future change, after we agree on the syntax. compiler/hlds_goal.m: Generalize the existing promise_equivalent_solutions scope to a promise_solutions scope with a flag that says whether in the source code it was originally the existing "promise_equivalent_solutions" construct or the new construct (which doesn't exist yet, but is indicated by the symbol "same_solutions" for now). Replace the conj and par_conj hlds_goal_exprs with a single goal expression: conj with an additional argument which is either plain_conj or parallel_conj. This was part of an earlier design in which a third kind of disjunction took the role now assigned to the new kind of promise_solutions scope, but turned out to be a good idea anyway, since in many places the compiler does treat the two kinds of conjunctions the same. This part of the change is responsible for the fact that this change results in a net *reduction* of about 40 lines. Move the most frequently used kinds of goal expressions to the front of the type declaration to allow the compiler to make better decisions about tag allocation. Add the goal marker we will add to the deconstructions in the first item. Replace the true_goal and fail_goal predicates with functions to make them easier to use, and rename their variants that take a context argument to avoid unnecessary ambiguity. compiler/*.m: Conform to the change in hlds_goal.m. Misc changes to make code more robust, e.g. replacing semidet predicates on goal expressions with functions returning bool. Misc cleanups, e.g. removal of unnecessary module qualifications that made lines too long, renaming predicates whose names include "disj" if they are also used to process parallel conjunctions (since in both parallel conjunctions and in disjunctions the goals are independent), and turning semidet predicates that switch on goal expressions into bool functions (to make similar changes more rebust in the future). |
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Julien Fischer
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5f589e98fb |
Various cleanups for the modules in the compiler directory.
Estimated hours taken: 4 Branches: main Various cleanups for the modules in the compiler directory. The are no changes to algorithms except the replacement of some if-then-elses that would naturally be switches with switches and the replacement of most of the calls to error/1. compiler/*.m: Convert calls to error/1 to calls to unexpected/2 or sorry/2 as appropriate throughout most or the compiler. Fix inaccurate assertion failure messages, e.g. identifying the assertion failure as taking place in the wrong module. Add :- end_module declarations. Fix formatting problems and bring the positioning of comments into line with our current coding standards. Fix some overlong lines. Convert some more modules to 4-space indentation. Fix some spots where previous conversions to 4-space indentation have stuffed the formatting of the code up. Fix a bunch of typos in comments. Use state variables in more places; use library predicates from the sv* modules where appropriate. Delete unnecessary and duplicate module imports. Misc. other small cleanups. |
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Zoltan Somogyi
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f9fe8dcf61 |
Improve the error messages generated for determinism errors involving committed
Estimated hours taken: 8
Branches: main
Improve the error messages generated for determinism errors involving committed
choice contexts. Previously, we printed a message to the effect that e.g.
a cc pred is called in context that requires all solutions, but we didn't say
*why* the context requires all solutions. We now keep track of all the goals
to the right that could fail, since it is these goals that may reject the first
solution of a committed choice goal.
The motivation for this diff was the fact that I found that locating the
failing goal can be very difficult if the conjunction to the right is
a couple of hundred lines long. This would have been a nontrivial problem,
since (a) unifications involving values of user-defined types are committed
choice goals, and (b) we can expect uses of user-defined types to increase.
compiler/det_analysis.m:
Keep track of goals to the right of the current goal that could fail,
and include them in the error representation if required.
compiler/det_report.m:
Include the list of failing goals to the right in the representations
of determinism errors involving committed committed choice goals.
Convert the last part of this module that wasn't using error_util
to use error_util. Make most parts of this module just construct
error message specifications; print those specifications (using
error_util) in only a few places.
compiler/hlds_out.m:
Add a function for use by the new code in det_report.m.
compiler/error_util.m:
Add a function for use by the new code in det_report.m.
compiler/error_util.m:
compiler/compiler_util.m:
Error_util is still changing reasonably often, and yet it is
included in lots of modules, most of which need only a few simple
non-parse-tree-related predicates from it (e.g. unexpected).
Move those predicates to a new module, compiler_util.m. This also
eliminates some undesirable dependencies from libs to parse_tree.
compiler/libs.m:
Include compiler_util.m.
compiler/notes/compiler_design.html:
Document compiler_util.m, and fix the documentation of some other
modules.
compiler/*.m:
Import compiler_util instead of or in addition to error_util.
To make this easier, consistently use . instead of __ for module
qualifying module names.
tests/invalid/det_errors_cc.{m,err_exp}:
Add this new test case to test the error messages for cc contexts.
tests/invalid/det_errors_deet.{m,err_exp}:
Add this new test case to test the error messages for unifications
inside function symbols.
tests/invalid/Mmakefile:
Add the new test cases.
tests/invalid/det_errors.err_exp:
tests/invalid/magicbox.err_exp:
Change the expected output to conform to the change in det_report.m,
which is now more consistent.
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Zoltan Somogyi
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b2012c0c0e |
Rename the types 'type', 'inst' and 'mode' to 'mer_type', 'mer_inst'
Estimated hours taken: 8 Branches: main compiler/*.m: Rename the types 'type', 'inst' and 'mode' to 'mer_type', 'mer_inst' and 'mer_mode'. This is to avoid the need to parenthesize these type names in some contexts, and to prepare for the possibility of a parser that considers those words to be reserved words. Rename some other uses of those names (e.g. as item types in recompilation.m). Delete some redundant synonyms (prog_type, mercury_type) for mer_type. Change some type names (e.g. mlds__type) and predicate names (e.g. deforest__goal) to make them unique even without module qualification. Rename the function symbols (e.g. pure, &) that need to be renamed to avoid the need to parenthesize them. Make their replacement names more expressive. Convert some more modules to four space indentation. Avoid excessively long lines, such as those resulting from the automatic substitution of 'mer_type' for 'type'. |
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Zoltan Somogyi
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905e4a114f |
Convert a bunch of modules to four-space indentation.
Estimated hours taken: 4 Branches: main compiler/*.m: Convert a bunch of modules to four-space indentation. In the process, fix departures from our coding standards. In some cases, do minor other cleanups such as changing argument orders to be friendly to state variables. There are no algorithmic changes. |
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Mark Brown
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38d9ef3479 |
Package the type_info_varmap and typeclass_info_varmap types into an ADT
Estimated hours taken: 25 Branches: main Package the type_info_varmap and typeclass_info_varmap types into an ADT called rtti_varmaps. There are two main purposes for this: - We wish to extend this set of maps with new maps. Doing this will be a lot easier and less error prone if all of the maps are packaged in a single data structure. - Any new maps that we add may contain redundant information that just makes searching the maps more efficient. Therefore they must be kept consistent with the existing maps. Having all the maps inside an ADT makes it easier to ensure this. This change also includes two extensions to the maps. First, the typeclass_info_map is made reversible so that it is possible to efficiently look up the constraint for a given typeclass_info variable. Second, a new map from prog_vars to types makes it possible to efficiently look up the type that a given type_info variable is for. These two changes mean that it is no longer necessary to consult the argument of type_info/1 or typeclass_info/1 to find this information. (We still do put that information there, though; changing the RTTI is left for a separate change.) compiler/hlds_pred.m: Move items relating to type_infos and typeclass_infos into a section of their own. Add a type `rtti_var_info' to hold information about the contents of a type_info or typeclass_info variable. Define the rtti_varmaps abstract data type. This data structure consists of the type_info_varmap and the typeclass_info_varmap. Add a new map, type_info_type_map, which is like the inverse to the type_info_varmap. The difference is that the latter can point to locations that are inside a typeclass_info variable, whereas the former only refers to type_info variables. Note that the combined maps do not form a bijection, or even an injection, since it is possible for two different type variables to point to the same location (that is, if they are aliased). Make the typeclass_info_varmap reversible, by using the new module injection.m. Unlike the type_info_varmap, this map is always injective since the same typeclass_info cannot be used for two different constraints. The predicates rtti_det_insert_type_info_locn and set_type_info_locn, which update the type_info_varmap, contain sanity checks to ensure that only type variables that have already been registered with the type_info_type_map are used, and that the information in both maps is consistent. Use the rtti_varmaps structure in proc_info and clauses_info, in place of type_info_varmap and typeclass_info_varmap. compiler/polymorphism.m: Remove polymorphism__type_info_or_ctor_type/2 and polymorphism__typeclass_info_class_constraint/2, to ensure that nobody tries to use the information in the type argument. Replace them with two similar predicates that test if a type is type_info or typeclass_info, but that don't return the argument. Ensure that the new type_info_type_map in the rtti_varmaps is kept up to date by threading the rtti_varmaps through a few more places. Some of these places are exported, so this part of the change affects other modules as well. Fix a comment that referred to a non-existent predicate. compiler/type_util.m: Remove the predicates apply_substitutions_to_var_map/5 and apply_substitutions_to_typeclass_var_map/5. The functionality is now provided by the new ADT. compiler/cse_detection.m: Rewrite update_existential_data_structures/4 to use the interface provided by rtti_varmaps. The algorithm for doing this has changed in the following ways: - The first pass, which builds a map from changed locations in the first branch to the tvars concerned, is modified slightly to traverse over the keys instead of over key-value pairs. - The second pass, which previously calculated the induced type substitution and reconstructed the type_info_varmap now only does the former. - Applying the prog_var transformation and the induced type substitution is done at the end, using the interface to rtti_varmaps. compiler/goal_util.m: Rewrite goal_util__extra_nonlocal_typeinfos/6 to avoid the need for using map__member/3 on the typeclass_info_varmap (about which the existing comments say "this is probably not very efficient..."), and to be more efficient in general. Previously, we nondeterministically generated non-local type vars and then tested each constraint to see if it had the type var in it. Now, we go through each constraint one at a time and check if any of the type variables in it are non-local. This is more efficient because we only need to find one non-local type in order to include the typeclass_info in the non-locals -- the remaining (duplicate) solutions are pruned away. compiler/higher_order.m: Use the new maps instead of looking at the arguments of type_info/1 and typeclass_info/1 types. We plan to remove this information from type_info and typeclass_info types in future. Previously, this module used the type argument in order to update the varmaps when the curried arguments of a higher order call are added as arguments to the procedure in which the call occurs. We now look up this information at the point where the curried arg variables are known, and store this information in higher_order_arg alongside the types where it used to be stored. This structure is threaded through to the place where the information is needed. Fix a cut and paste bug in higher_order_arg_depth/1. It was previously calling higher_order_args_size/1 in the recursive call, instead of calling higher_order_args_depth/1. compiler/inlining.m: In inlining__do_inline_call, apply the substitutions to the entire rtti_varmaps structure, not just to the type_info_varmap. (XXX Is there a good reason why the substitution should _not_ be applied to the typeclass_info varmap?) compiler/magic_util.m: Avoid using polymorphism__type_info_or_ctor_type/2 and polymorphism__typeclass_info_class_constraint/2, as these are no longer supported. compiler/*.m: Straightforward changes to use the new ADT. library/injection.m: New library module. This provides an `injection' type which is similar to the existing `bimap' type in that it implements back-to-back maps, but doesn't have such stringent invariants imposed. In particular, the reverse map is not required to be injective. This type is used to model the relationship between prog_constraints and program variables that hold typeclass_infos for them. Namely, the typeclass_info for a constraint can be held in two different variables, but one variable can never hold the typeclass_info for two distinct constraints. library/library.m: Add the new library module. library/list.m: Add list__foldl_corresponding and list__foldl2_corresponding, which traverse two lists in parallel, which one or two accumulators, and abort if there is a length mismatch. NEWS: Mention the changes to the standard library. |
||
|
Zoltan Somogyi
|
8b8b3b7d3f |
Replace the some() HLDS goal with a more general scope() goal, which can be
Estimated hours taken: 12
Branches: main
Replace the some() HLDS goal with a more general scope() goal, which can be
used not just for existential quantification but also for other purposes.
The main such purposes are new goal types that allow the programmer
to annotate arbitrary goals, and not just whole procedure bodies, with the
equivalents of promise_pure/promise_semipure and promise_only_solution:
promise_pure ( <impure/semipure goal> )
promise_semipure ( <impure goal> )
promise_equivalent_solutions [OutVar1, OutVar2] (
<cc_multi/cc_nondet goal that computed OutVar1 & OutVar2>
)
Both are intended to be helpful in writing constraint solvers, as well as in
other situations.
doc/reference_manual.texi:
Document the new constructs.
library/ops.m:
Add the keywords of the new constructs to the list of operators.
Since they work similarly to the "some" operator, they have the same
precedence.
compiler/hlds_goal.m:
Replace the some(Vars, SubGoal) HLDS construct, with its optional
keep_this_commit attribute, with the new scope(Reason, SubGoal)
construct. The Reason argument may say that this scope is an
existential quantification, but it can also say that it represents
a purity promise, the introduction of a single-solution context
with promise_equivalent_solutions, or a decision by a compiler pass.
It can also say that the scope represents a set of goals that all arise
from the unraveling of a unification between a variable and a ground
term. This was intended to speed up mode checking by significantly
reducing the number of delays and wakeups, but the cost of the scopes
themselves turned out to be bigger than the gain in modechecking speed.
Update the goal_path_step type to refer to scope goals instead of just
existential quantification.
compiler/prog_data.m:
Add new function symbols to the type we use to represent goals in items
to stand for the new Mercury constructs.
compiler/prog_io_goal.m:
Add code to read in the new language constructs.
compiler/prog_io_util.m:
Add a utility predicate for use by the new code in prog_io_goal.m.
compiler/make_hlds.m:
Convert the item representation of the new constructs to the HLDS
representation.
Document how the from_ground_term scope reason would work, but do not
enable the code.
compiler/purity.m:
When checking the purity of goals, respect the new promise_pure and
promise_semipure scopes. Generate warnings if such scopes are
redundant.
compiler/det_analysis.m:
Make the insides of promise_equivalent_solutions goals single solution
contexts.
compiler/det_report.m:
Provide mechanisms for reporting inappropriate usage of
promise_equivalent_solutions goals.
compiler/instmap.m:
Add a utility predicate for use by one of the modules above.
compiler/deep_profiling.m:
Use one of the new scope reasons to prevent simplify from optimizing
away commits of goals that have been made impure, instead of the old
keep_this_commit goal feature.
compiler/modes.m:
Handle from_ground_term scopes when present; for now, they won't be
present, since make_hlds isn't creating them.
compiler/options.m:
Add two new compiler options, for use by implementors only, to allow
finer control over the amount of output one gets with --debug-modes.
(I used them when debugging the performance of the from_ground_term
scope reason.) The options are --debug-modes-minimal and
--debug-modes-verbose.
compiler/handle_options.m:
Make the options that are meaningful only in the presence of
--debug-modes imply --debug-modes, since this allows more convenient
(shorter) invocations.
compiler/mode_debug.m:
Respect the new options when deciding how much data to print
when debugging of the mode checking process is enabled.
compiler/switch_detect.m:
Rename a predicate to make it differ from another predicate by more
than just its arity.
compiler/passes_aux.m:
Bring this module up to date with our current style guidelines,
by using state variable syntax where appropriate.
compiler/*.m:
Minor changes to conform to the change in the HLDS and/or parse tree
goal type.
mdbcomp/program_representation.m:
Rename the some goal to the scope goal, and the same for path steps,
to keep them in sync with the HLDS.
browser/declarative_tree.m:
Conform to the change in goal representations.
tests/hard_coded/promise_equivalent_solutions_test.{m,exp}:
A new test case to test the handling of the
promise_equivalent_solutions construct.
tests/hard_coded/Mmakefile:
Enable the new test.
tests/hard_coded/purity/promise_pure_test.{m,exp}:
A new test case to test the handling of the promise_pure and
promise_semipure constructs.
tests/hard_coded/purity/Mmakefile:
Enable the new test.
tests/invalid/promise_equivalent_solutions.{m,err_exp}:
A new test case to test the error messages for improper use of the
promise_pure and promise_semipure constructs.
tests/invalid/Mmakefile:
Enable the new test.
|
||
|
Zoltan Somogyi
|
c08ca7fbc8 |
Import only one module per line in the modules of the compiler
Estimated hours taken: 3 Branches: main compiler/*.m: Import only one module per line in the modules of the compiler where my previous diff did not already do so. Misc other cleanups. Where relevant, use the new mechanism in tree.m. compiler/tree.m: Fix a performance problem I noticed while update :- import_module items. Instead of supplying a function to convert lists of trees to a tree, make the tree data structure able to hold a list of subtrees directly. This reduces the number of times where we have to convert list of trees to trees that are sticks just to stay within the old definition of what a tree is. |
||
|
Zoltan Somogyi
|
885fd4a387 |
Remove almost all dependencies by the modules of parse_tree.m on the modules
Estimated hours taken: 12 Branches: main Remove almost all dependencies by the modules of parse_tree.m on the modules of hlds.m. The only such dependencies remaining now are on type_util.m. compiler/hlds_data.m: compiler/prog_data.m: Move the cons_id type from hlds_data to prog_data, since several parts of the parse tree data structure depend on it (particularly insts). Remove the need to import HLDS modules in prog_data.m by making the cons_ids that refer to procedure ids refer to them via a new type that contains shrouded pred_ids and proc_ids. Since pred_ids and proc_ids are abstract types in hlds_data, add predicates to hlds_data to shroud and unshroud them. Also move some other types, e.g. mode_id and class_id, from hlds_data to prog_data. compiler/hlds_data.m: compiler/prog_util.m: Move predicates for manipulating cons_ids from hlds_data to prog_util. compiler/inst.m: compiler/prog_data.m: Move the contents of inst.m to prog_data.m, since that is where it belongs, and since doing so eliminates a circular dependency. The separation doesn't serve any purpose any more, since we don't need to import hlds_data.m anymore to get access to the cons_id type. compiler/mode_util.m: compiler/prog_mode.m: compiler/parse_tree.m: Move the predicates in mode_util that don't depend on the HLDS to a new module prog_mode, which is part of parse_tree.m. compiler/notes/compiler_design.m: Mention prog_mode.m, and delete the mention of inst.m. compiler/mercury_to_mercury.m: compiler/hlds_out.m: Move the predicates that depend on HLDS out of mercury_to_mercury.m to hlds_out.m. Export from mercury_to_mercury.m the predicates needed by the moved predicates. compiler/hlds_out.m: compiler/prog_out.m: Move predicates for printing parts of the parse tree out of hlds_out.m to prog_out.m, since mercury_to_mercury.m needs to use them. compiler/purity.m: compiler/prog_out.m: Move predicates for printing purities from purity.m, which is part of check_hlds.m, to prog_out.m, since mercury_to_mercury.m needs to use them. compiler/passes_aux.m: compiler/prog_out.m: Move some utility predicates (e.g. for printing progress messages) from passes_aux.m to prog_out.m, since some predicates in submodules of parse_tree.m need to use them. compiler/foreign.m: compiler/prog_data.m: Move some types from foreign.m to prog_data.m to allow the elimination of some dependencies on foreign.m from submodules of parse_tree.m. compiler/*.m: Conform to the changes above, mostly by updating lists of imported modules and module qualifications. In some cases, also do some local cleanups such as converting predicate declarations to predmode syntax and fixing white space. |
||
|
Zoltan Somogyi
|
7bf0cd03af |
Reduce the overhead of all forms of tabling by eliminating in many cases
Estimated hours taken: 32
Branches: main
Reduce the overhead of all forms of tabling by eliminating in many cases
the overhead of transferring data across the C/Mercury boundary. These
involve lots of control transfers as well as assignments to and from
Mercury abstract machine registers, which are not real machine registers
on x86 machines. Benchmarking in Uppsala revealed this overhead to be
a real problem.
The way we do that is by changing the tabling transformation so that instead
of generating sequences of calls to predicates from library/table_builtin.m,
we generate sequences of calls to C macros from runtime/mercury_tabling_pred.h,
and emit the resulting code string as the body of a foreign_proc goal.
(The old transformation is still available via a new option,
--no-tabling-via-extra-args.)
Since the number of inputs and outputs of the resulting C code sequences
are not always fixed (they can depend on the number of input or output
arguments of predicate being transformed), implementing this required
adding to foreign_procs a new field that allows the specification of extra
arguments to be passed to and from the given foreign code fragment. For now,
this mechanism is implemented only by the C backends, since it is needed
only by the C backends. (We don't support yet tabling on other backends.)
To simplify the new implementation of the field on foreign_procs, consolidate
three existing fields into one. Each of these fields was a list with one
element per argument, so turning them into a single list with a combined record
per argument should also improve reliability, since it reduces the likelyhood
of updates leaving the data structure inconsistent.
The goal paths of components of a tabled predicate depend on whether
-no-tabling-via-extra-args was specified. To enable the expected outputs
of the debugger test cases testing tabling, we add a new mdb command,
goal_paths, that controls whether goal paths are printed by the debugger
at events, and turn off the printing of events in the relevant test cases.
Also, prepare for a future change to optimize the trie structure for
user-defined types by handling type_infos (and once we support them,
typeclass_infos) specially.
compiler/table_gen.m:
Change the tabling transformation along the lines described above.
To allow us to factor out as much of the new code as possible,
we change the meaning of the call_table_tip variable for minimal
model subgoals: instead of the trie node at the end of the answer
table, it is not now the subgoal reachable from it. This change
has no effect as yet, because we use call_table_tip variables
only to perform resets across retries in the debugger, and we
don't do retries across calls to minimal model tabled predicates.
Put predicates into logical groups.
library/table_builtin.m:
runtime/mercury_tabling_preds.h:
When the new transformations in table_gen.m generate foreign_procs
with variable numbers of arguments, the interfaces of those
foreign_procs often do not match the interfaces of the existing
library predicates at their core: they frequently have one more
or one fewer argument. To prevent any possible confusion, in such
cases we add a new variant of the predicate. These predicates
have the suffix _shortcut in their name. Their implementations
are dummy macros that do nothing; they serve merely as placeholders
before or after which the macros that actually do the work are
inserted.
Move the definitions of the lookup, save and restore predicates
into mercury_tabling_preds.h. Make the naming scheme of their
arguments more regular.
runtime/mercury_minimal_model.c:
runtime/mercury_tabling_preds.h:
Move the definition of a predicate from mercury_minimal_model.c
to mercury_tabling_preds.h, since the compiler now needs to be
able to generate an inlined version of it.
compiler/hlds_goal.m:
Replace the three existing fields describing the arguments of
foreign_procs with one, and add a new field describing the extra
arguments that may be inserted by table_gen.m.
Add utility predicates for processing the arguments of foreign_procs.
Change the order of some existing groups of declarations make it
more logical.
compiler/hlds_pred.m:
runtime/mercury_stack_layout.h:
Extend the data structures recording the structure of tabling tries
to allow the representation of trie steps for type_infos and
typeclass_infos.
runtime/mercury_tabling_macros.c:
Fix a bug regarding the tabling of typeclass_infos, which is now
required for a clean compile.
compiler/pragma_c_gen.m:
compiler/ml_code_gen.m:
Modify the generation of code for foreign_procs to handle extra
arguments, and to conform to the new data structures for foreign_proc
arguments.
compiler/llds.m:
The tabling transformations can now generate significantly sized
foreign_procs bodies, which the LLDS code generator translates to
pragma_c instructions. Duplicating these by jump optimization
may lose more by worsening locality than it gains in avoiding jumps,
so we add an extra field to pragma_c instructions that tells jumpopt
not to duplicate code sequences containing such pragma_cs.
compiler/jumpopt.m:
Respect the new flag on pragma_cs.
compiler/goal_util.m:
Add a predicate to create foreign_procs with specified contents,
modelled on the existing predicate to create calls.
Change the order of the arguments of that existing predicate
to make it more logical.
compiler/polymorphism.m:
Conform to the new definition of foreign_procs. Try to simplify
the mechanism for generating the type_info and typeclass_info
arguments of foreign_proc goals, but it is not clear that this
code is even ever executed.
compiler/aditi_builtin_ops.m:
compiler/assertion.m:
compiler/bytecode_gen.m:
compiler/clause_to_proc.m:
compiler/code_gen.m:
compiler/code_info.m:
compiler/code_util.m:
compiler/constraint.m:
compiler/deep_profiling.m:
compiler/deforest.m:
compiler/delay_construct.m:
compiler/dependency_graph.m:
compiler/det_analysis.m:
compiler/det_report.m:
compiler/dnf.m:
compiler/dupelim.m:
compiler/equiv_type_hlds.m:
compiler/exprn_aux.m:
compiler/follow_code.m:
compiler/follow_vars.m:
compiler/frameopt.m:
compiler/goal_form.m:
compiler/goal_path.m:
compiler/higher_order.m:
compiler/higher_order.m:
compiler/hlds_module.m:
compiler/hlds_out.m:
compiler/inlining.m:
compiler/ite_gen.m:
compiler/layout_out.m:
compiler/livemap.m:
compiler/liveness.m:
compiler/llds_out.m:
compiler/loop_inv.m:
compiler/magic.m:
compiler/make_hlds.m:
compiler/mark_static_terms.m:
compiler/middle_rec.m:
compiler/modes.m:
compiler/modules.m:
compiler/opt_debug.m:
compiler/pd_cost.m:
compiler/prog_rep.m:
compiler/purity.m:
compiler/quantification.m:
compiler/reassign.m:
compiler/rl_exprn.m:
compiler/saved_vars.m:
compiler/simplify.m:
compiler/size_prof.m:
compiler/store_alloc.m:
compiler/stratify.m:
compiler/switch_detection.m:
compiler/term_pass1.m:
compiler/term_traversal.m:
compiler/termination.m:
compiler/trace.m:
compiler/typecheck.m:
compiler/unify_proc.m:
compiler/unique_modes.m:
compiler/unneeed_code.m:
compiler/unused_args.m:
compiler/use_local_vars.m:
Conform to the new definition of foreign_procs, pragma_cs and/or
table trie steps, or to changed argument orders.
compiler/add_heap_ops.m:
compiler/add_trail_ops.m:
compiler/cse_detection.m:
compiler/dead_proc_elim.m:
compiler/equiv_type.m:
compiler/intermod.m:
compiler/lambda.m:
compiler/lco.m:
compiler/module_util.m:
compiler/opt_util.m:
compiler/stack_opt.m:
compiler/trans_opt.m:
Conform to the new definition of foreign_procs.
Bring these modules up to date with our current code style guidelines,
using predmode declarations, state variable syntax and unification
expressions as appropriate.
compiler/mercury_compile.m:
Conform to the changed argument order of a predicate in trans_opt.m.
compiler/options.m:
Add the --no-tabling-via-extra-args option, but leave the
documentation commented out since the option is for developers only.
doc/user_guide.texi:
Document --no-tabling-via-extra-args option, though leave the
documentation commented out since the option is for developers only.
doc/user_guide.texi:
doc/mdb_categories:
Document the new goal_paths mdb command.
trace/mercury_trace_internals.c:
Implement the new goal_paths mdb command.
tests/debugger/completion.exp:
Conform to the presence of the goal_paths mdb command.
tests/debugger/mdb_command_test.inp:
Test the existence of documentation for the goal_paths mdb command.
tests/debugger/print_table.{inp,exp*}:
tests/debugger/retry.{inp,exp*}:
Use the goal_paths command to avoid having the expected output
depend on the presence or absence of --tabling-via-extra-args.
tests/tabling/table_foreign_output.{m,exp}:
Add a new test case to test the save/restore of arguments of foreign
types.
tests/tabling/Mmakefile:
Enable the new test case.
tests/tabling/test_tabling:
Make this script more robust.
Add an option for testing only the standard model forms of tabling.
|
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|
Zoltan Somogyi
|
ff60134ee9 |
Bring these modules up to our current coding standards.
Estimated hours taken: 8 Branches: main analysis/analysis.m: browser/browse.m: compiler/accumulator.m: compiler/assertion.m: compiler/atsort.m: compiler/c_util.m: compiler/check_typeclass.m: compiler/clause_to_proc.m: compiler/code_gen.m: compiler/code_model.m: compiler/const_prop.m: compiler/constraint.m: compiler/dead_proc_elim.m: compiler/delay_construct.m: compiler/dependency_graph.m: compiler/det_analysis.m: compiler/det_report.m: compiler/export.m: compiler/fact_table.m: compiler/follow_code.m: compiler/graph_colour.m: compiler/hlds_module.m: compiler/inlining.m: compiler/llds.m: compiler/make_hlds.m: compiler/mercury_to_mercury.m: compiler/ml_tailcall.m: compiler/ml_unify_gen.m: compiler/mmc_analysis.m: compiler/mode_errors.m: compiler/passes_aux.m: compiler/post_typecheck.m: compiler/size_prof.m: compiler/switch_util.m: compiler/table_gen.m: compiler/term_errors.m: compiler/transform_llds.m: compiler/type_util.m: compiler/unify_gen.m: compiler/unneeded_code.m: compiler/unused_args.m: Bring these modules up to our current coding standards. Use predmode declarations and state variable syntax where relevant. Reorder arguments where this is needed for the use state variables. Make the orders of predicate definitions correspond to the order of their declarations. Replace some overly large lambda expressions with named predicates. Convert some predicates to functions where this makes their use more convenient. Use field access notation where convenient. Fix any inconsistent indentation. Remove module prefixes on predicate names where this is necessary to allow sane indentation. In several places, use predicates from error_util.m to print error messages. Apart from this, there are no changes in algorithms. In some places, conform to the changes below. compiler/error_util.m: compiler/hlds_error_util.m: Add new variants of existing predicates for use in some of the changed modules above. compiler/hlds_out.m: Add some functions to convert values of some HLDS types as strings, for use in preparing the arguments of the new calls to predicates in error_util.m. Change the implementations of the predicates that print values of those types to call those functions instead of allowing code duplication. compiler/llds.m: Add some field names to allow use of field updates where relevant. tests/invalid/assert_in_interface.err_exp: tests/invalid/multisoln_func.err_exp: tests/invalid/tricky_assert1.err_exp: Update the expected outputs of these test cases to allow for them being generated by error_util.m, and hence being better formatted than before. |
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|
Zoltan Somogyi
|
8693e293a2 |
This diff makes hlds_pred.m and many callers of its predicates easier to read
Estimated hours taken: 4 Branches: main This diff makes hlds_pred.m and many callers of its predicates easier to read and to maintain, but contains no changes in algorithms whatsoever. compiler/hlds_pred.m: Bring this module into line with our current coding standards. Use predmode declarations, functions, and state variable syntax when appropriate. Reorder arguments of predicates where necessary for the use of state variable syntax, and where this improves readability. Replace old-style lambdas with new-style lambdas or with partially applied named procedures. Standardize indentation. compiler/*.m: Conform to the changes in hlds_pred.m. This mostly means using the new argument orders of predicates exported by hlds_pred.m. Where this is now conveniently possible, change predicates to use state variable notation. In some modules, using state variable notation required changing the orders of arguments in the module's top predicate. compiler/passes_aux.m: Change the order of arguments in the calls this module makes to allow the callees to use state variable notation. Convert this module to state variable notation too. |
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Zoltan Somogyi
|
9551640f55 |
Import only one compiler module per line. Sort the blocks of imports.
Estimated hours taken: 2 Branches: main compiler/*.m: Import only one compiler module per line. Sort the blocks of imports. This makes it easier to merge in changes. In a couple of places, remove unnecessary imports. |
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|
Zoltan Somogyi
|
189b9215ae |
This diff implements stack slot optimization for the LLDS back end based on
Estimated hours taken: 400
Branches: main
This diff implements stack slot optimization for the LLDS back end based on
the idea that after a unification such as A = f(B, C, D), saving the
variable A on the stack indirectly also saves the values of B, C and D.
Figuring out what subset of {B,C,D} to access via A and what subset to access
via their own stack slots is a tricky optimization problem. The algorithm we
use to solve it is described in the paper "Using the heap to eliminate stack
accesses" by Zoltan Somogyi and Peter Stuckey, available in ~zs/rep/stackslot.
That paper also describes (and has examples of) the source-to-source
transformation that implements the optimization.
The optimization needs to know what variables are flushed at call sites
and at program points that establish resume points (e.g. entries to
disjunctions and if-then-elses). We already had code to compute this
information in live_vars.m, but this code was being invoked too late.
This diff modifies live_vars.m to allow it to be invoked both by the stack
slot optimization transformation and by the code generator, and allows its
function to be tailored to the requirements of each invocation.
The information computed by live_vars.m is specific to the LLDS back end,
since the MLDS back ends do not (yet) have the same control over stack
frame layout. We therefore store this information in a new back end specific
field in goal_infos. For uniformity, we make all the other existing back end
specific fields in goal_infos, as well as the similarly back end specific
store map field of goal_exprs, subfields of this new field. This happens
to significantly reduce the sizes of goal_infos.
To allow a more meaningful comparison of the gains produced by the new
optimization, do not save any variables across erroneous calls even if
the new optimization is not enabled.
compiler/stack_opt.m:
New module containing the code that performs the transformation
to optimize stack slot usage.
compiler/matching.m:
New module containing an algorithm for maximal matching in bipartite
graphs, specialized for the graphs needed by stack_opt.m.
compiler/mercury_compile.m:
Invoke the new optimization if the options ask for it.
compiler/stack_alloc.m:
New module containing code that is shared between the old,
non-optimizing stack slot allocation system and the new, optimizing
stack slot allocation system, and the code for actually allocating
stack slots in the absence of optimization.
Live_vars.m used to have two tasks: find out what variables need to be
saved on the stack, and allocating those variables to stack slots.
Live_vars.m now does only the first task; stack_alloc.m now does
the second, using code that used to be in live_vars.m.
compiler/trace_params:
Add a new function to test the trace level, which returns yes if we
want to preserve the values of the input headvars.
compiler/notes/compiler_design.html:
Document the new modules (as well as trace_params.m, which wasn't
documented earlier).
compiler/live_vars.m:
Delete the code that is now in stack_alloc.m and graph_colour.m.
Separate out the kinds of stack uses due to nondeterminism: the stack
slots used by nondet calls, and the stack slots used by resumption
points, in order to allow the reuse of stack slots used by resumption
points after execution has left their scope. This should allow the
same stack slots to be used by different variables in the resumption
point at the start of an else branch and nondet calls in the then
branch, since the resumption point of the else branch is not in effect
when the then branch is executed.
If the new option --opt-no-return-calls is set, then say that we do not
need to save any values across erroneous calls.
Use type classes to allow the information generated by this module
to be recorded in the way required by its invoker.
Package up the data structures being passed around readonly into a
single tuple.
compiler/store_alloc.m:
Allow this module to be invoked by stack_opt.m without invoking the
follow_vars transformation, since applying follow_vars before the form
of the HLDS code is otherwise final can be a pessimization.
Make the module_info a part of the record containing the readonly data
passed around during the traversal.
compiler/common.m:
Do not delete or move around unifications created by stack_opt.m.
compiler/call_gen.m:
compiler/code_info.m:
compiler/continuation_info.m:
compiler/var_locn.m:
Allow the code generator to delete its last record of the location
of a value when generating code to make an erroneous call, if the new
--opt-no-return-calls option is set.
compiler/code_gen.m:
Use a more useful algorithm to create the messages/comments that
we put into incr_sp instructions, e.g. by distinguishing between
predicates and functions. This is to allow the new scripts in the
tool directory to gather statistics about the effect of the
optimization on stack frame sizes.
library/exception.m:
Make a hand-written incr_sp follow the new pattern.
compiler/arg_info.m:
Add predicates to figure out the set of input, output and unused
arguments of a procedure in several different circumstances.
Previously, variants of these predicates were repeated in several
places.
compiler/goal_util.m:
Export some previously private utility predicates.
compiler/handle_options.m:
Turn off stack slot optimizations when debugging, unless
--trace-optimized is set.
Add a new dump format useful for debugging --optimize-saved-vars.
compiler/hlds_llds.m:
New module for handling all the stuff specific to the LLDS back end
in HLDS goal_infos.
compiler/hlds_goal.m:
Move all the relevant stuff into the new back end specific field
in goal_infos.
compiler/notes/allocation.html:
Update the documentation of store maps to reflect their movement
into a subfield of goal_infos.
compiler/*.m:
Minor changes to accomodate the placement of all back end specific
information about goals from goal_exprs and individual fields of
goal_infos into a new field in goal_infos that gathers together
all back end specific information.
compiler/use_local_vars.m:
Look for sequences in which several instructions use a fake register
or stack slot as a base register pointing to a cell, and make those
instructions use a local variable instead.
Without this, a key assumption of the stack slot optimization,
that accessing a field in a cell costs only one load or store
instruction, would be much less likely to be true. (With this
optimization, the assumption will be false only if the C compiler's
code generator runs out of registers in a basic block, which for
the code we generate should be unlikely even on x86s.)
compiler/options.m:
Make the old option --optimize-saved-vars ask for both the old stack
slot optimization (implemented by saved_vars.m) that only eliminates
the storing of constants in stack slots, and the new optimization.
Add two new options --optimize-saved-vars-{const,cell} to turn on
the two optimizations separately.
Add a bunch of options to specify the parameters of the new
optimizations, both in stack_opt.m and use_local_vars.m. These are
for implementors only; they are deliberately not documented.
Add a new option, --opt-no-return-cells, that governs whether we avoid
saving variables on the stack at calls that cannot return, either by
succeeding or by failing. This is for implementors only, and thus
deliberately documented only in comments. It is enabled by default.
compiler/optimize.m:
Transmit the value of a new option to use_local_vars.m.
doc/user_guide.texi:
Update the documentation of --optimize-saved-vars.
library/tree234.m:
Undo a previous change of mine that effectively applied this
optimization by hand. That change complicated the code, and now
the compiler can do the optimization automatically.
tools/extract_incr_sp:
A new script for extracting stack frame sizes and messages from
stack increment operations in the C code for LLDS grades.
tools/frame_sizes:
A new script that uses extract_incr_sp to extract information about
stack frame sizes from the C files saved from a stage 2 directory
by makebatch and summarizes the resulting information.
tools/avg_frame_size:
A new script that computes average stack frame sizes from the files
created by frame_sizes.
tools/compare_frame_sizes:
A new script that compares the stack frame size information
extracted from two different stage 2 directories by frame_sizes,
reporting on both average stack frame sizes and on specific procedures
that have different stack frame sizes in the two versions.
|
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|
Fergus Henderson
|
7597790760 |
Use sub-modules to structure the modules in the Mercury compiler directory.
The main aim of this change is to make the overall, high-level structure of the compiler clearer, and to encourage better encapsulation of the major components. compiler/libs.m: compiler/backend_libs.m: compiler/parse_tree.m: compiler/hlds.m: compiler/check_hlds.m: compiler/transform_hlds.m: compiler/bytecode_backend.m: compiler/aditi_backend.m: compiler/ml_backend.m: compiler/ll_backend.m: compiler/top_level.m: New files. One module for each of the major components of the Mercury compiler. These modules contain (as separate sub-modules) all the other modules in the Mercury compiler, except gcc.m and mlds_to_gcc.m. Mmakefile: compiler/Mmakefile: Handle the fact that the top-level module is now `top_level', not `mercury_compile' (since `mercury_compile' is a sub-module of `top_level'). compiler/Mmakefile: Update settings of *FLAGS-<modulename> to use the appropriate nested module names. compiler/recompilation_check.m: compiler/recompilation_version.m: compiler/recompilation_usage.m: compiler/recompilation.check.m: compiler/recompilation.version.m: compiler/recompilation.version.m: Convert the `recompilation_*' modules into sub-modules of the `recompilation' module. compiler/*.m: compiler/*.pp: Module-qualify the module names in `:- module', `:- import_module', and `:- use_module' declarations. compiler/base_type_info.m: compiler/base_type_layout.m: Deleted these unused empty modules. compiler/prog_data.m: compiler/globals.m: Move the `foreign_language' type from prog_data to globals. compiler/mlds.m: compiler/ml_util.m: compiler/mlds_to_il.m: Import `globals', for `foreign_language'. Mmake.common.in: trace/Mmakefile: runtime/Mmakefile: Rename the %.check.c targets as %.check_hdr.c, to avoid conflicts with compiler/recompilation.check.c. |
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|
Zoltan Somogyi
|
afd6568f4e |
A new module for delaying construction unifications past builtins in
Estimated hours taken: 8 Branches: main compiler/delay_construct.m: A new module for delaying construction unifications past builtins in conjunctions that can fail. The idea is to incur the cost of memory allocation only if those tests succeed. This can speed up code (e.g. tests/benchmarks/query) by integer factors. compiler/notes/compiler_design.m: Mention the new module. compiler/options.m: doc/user_guide.texi: Add a new option, --delay-construct, that switches on the new optimization. compiler/mercury_compile.m: Invoke the new optimization if the option calls for it. |