library/fatter_sparse_bitset.m:
Add this version of fat_sparse_bitset.m, which stores *two* words
worth of bits in each cell, not one. This word would otherwise be unused,
because the Boehm-Demers-Weiser allocator rounds up requests for three
word cells to four.
library/MODULES_DOC:
library/library.m:
Add the new module to the list of library modules.
library/fat_sparse_bitset.m:
library/sparse_bitset.m:
library/tree_bitset.m:
Update the documentation of all these other bitset modules. Copy
the same basic introduction to all the relevant modules. Add documentation
of the differences to tree_bitset.m and fatter_sparse_bitset.m, with
a pointer in fat_sparse_bitset.m to fatter_sparse_bitset.m.
library/test_bitset.m:
Test the new module as well as the others.
tests/hard_coded/speedtest_bitset.m:
Extend the benchmarking of list_to_set operations to the new module.
To allow the benchmarking to be tough enough to be informative, comment
out the benchmarking of the old_list_to_set operations.
library/test_bitset.m:
Instead of comparing just one bitset module (tree_bitset by default)
against set_ordlist, compare all of them (tree_bitset, sparse_bitset,
and fat_sparse_bitset) against set_ordlist.
tests/hard_coded/test_bitsets.{m,exp}:
Rename this test case from test_tree_bitset to test_bitsets, since
(through library/test_bitset.m) we now test ALL bitset implementations,
not just tree_bitset.
tests/hard_coded/Mmakefile:
Refer to the test by its new name.
library/sparse_bitset.m:
library/fat_sparse_bitset.m:
Speed up the remove_leq and remove_gt operations by moving a
loop invariant computation, the conversion of the boundary item's index
into an <offset,bitposn> pair, out of the loop.
Eliminate some unnecessary differences between the two modules,
e.g. clear_bit being a predicate rather than a function.
library/test_bitset.m:
Add facilities to test the remove_leq and remove_gt operations
of sparse_bitset.m, fat_sparse_bitset.m, and tree_bitset.m
against the same operations on plain old set_ordlists.
Bring this module up to date by requiring set elements to be
members of the uenum typeclass, not the enum typeclass.
Make the test_bitset type a bespoke type.
library/tree_bitset.m:
Add predicate versions of the remove_leq and remove_gt operations
alongside the existing function versions, to allow the new code
in test_bitset.m to work the same way regardless of which bitset module
it is testing.
For uniformity with the other bitset modules, require set elements to be
members of the uenum typeclass, not the enum typeclass.
Change the other integers, such as level numbers, to be unsigned
as well, to avoid the need for casts.
NEWS:
Announce the new additions and changes.
tests/hard_coded/test_tree_bitset.{m,exp}:
Use those new facilities to test those operations, and add some
test sets designed for that purpose.
Add a comment about the limitations of this testing strategy.
tests/hard_coded/bitset_tester.m:
Delete this long-unused module. (It was the original basis of
the test_bitset.m module in the library directory, but it became unused
when test_tree_bitset.m switched to using that module a long time ago.)
library/diet.m:
library/fat_sparse_bitset.m:
library/sparse_bitset.m:
library/test_bitset.m:
library/tree_bitset.m:
As above. Also, mark as obsolete the same predicates as were marked obsolete
in the other set modules recently.
compiler/mode_robdd.equiv_vars.m:
compiler/mode_robdd.implications.m:
compiler/mode_robdd.tfeirn.m:
library/robdd.m:
library/digraph.m:
Avoid using predicates that are now marked obsolete.
Discussion of these changes can be found on the Mercury developers
mailing list archives from June 2018.
COPYING.LIB:
Add a special linking exception to the LGPL.
*:
Update references to COPYING.LIB.
Clean up some minor errors that have accumulated in copyright
messages.
If a module has two or more import_module or use_module declarations
for the same module, (typically, but not always, one being in its interface
and one in its implementation), generate an informational message about
each redundant declaration if --warn-unused-imports is enabled.
compiler/hlds_module.m:
We used to record the set of imported/used modules, and the set of
modules imported/used in the interface of the current module. However,
these sets
- did not record the distinction between imports and uses;
- did not allow distinction between single and multiple imports/uses;
- did not record the locations of the imports/uses.
The first distinction was needed only by module_qual.m, which *did*
pay attention to it; the other two were not needed at all.
To generate messages for imports/uses shadowing other imports/uses,
we need all three, so change the data structure storing such information
for *direct* imports to one that records all three of the above kinds
of information. (For imports made by read-in interface and optimization
files, the old set of modules approach is fine, and this diff leaves
the set of thus *indirectly* imported module names alone.)
compiler/unused_imports.m:
Use the extra information now available to generate a
severity_informational message about any import or use that is made
redundant by an earlier, more general import or use.
Fix two bugs in the code that generated warnings for just plain unused
modules.
(1) It did not consider that a use of the builtin type char justified
an import of char.m, but without that import, the type is not visible.
(2) It scanned cons_ids in goals in procedure bodies, but did not scan
cons_ids that have been put into the const_struct_db. (I did not update
the code here when I added the const_struct_db.)
Also, add a (hopefully temporary) workaround for a bug in
make_hlds_passes.m, which is noted below.
However, there are at least three problems that prevent us from enabling
--warn-unused-imports by default.
(1) In some places, the import of a module is used only by clauses for
a predicate that also has foreign procs. When compiled in a grade that
selects one of those foreign_procs as the implementation of the predicate,
the clauses are discarded *without* being added to the HLDS at all.
This leads unused_imports.m to generate an uncalled-for warning in such
cases. To fix this, we would need to preserve the Mercury clauses for
*all* predicates, even those with foreign procs, and do all the semantic
checks on them before throwing them away. (I tried to do this once, and
failed, but the task should be easier after the item list change.)
(2) We have two pieces of code to generate import warnings. The one in
unused_imports.m operates on the HLDS after type and mode checking,
while module_qual.m operates on the parse tree before the creation of
the HLDS. The former is more powerful, since it knows e.g. what types and
modes are used in the bodies of predicates, and hence can generate warnings
about an import being unused *anywhere* in a module, as opposed to just
unused in its interface.
If --warn-unused-imports is enabled, we will get two separate set of
reports about an interface import being unused in the interface,
*unless* we get a type or mode error, in which case unused_imports.m
won't be invoked. But in case we do get such errors, we don't want to
throw away the warnings from module_qual.m. We could store them and
throw them away only after we know we won't need them, or just get
the two modules to generate identical error_specs for each warning,
so that the sort_and_remove_dups of the error specs will do the
throwing away for us for free, if we get that far.
(3) The valid/bug100.m test case was added as a regression test for a bug
that was fixed in module_qual.m. However the bug is still present in
unused_imports.m.
compiler/make_hlds_passes.m:
Give hlds_module.m the extra information it now needs for each item_avail.
Add an XXX for a bug that cannot be fixed right now: the setting of
the status of abstract instances to abstract_imported. (The "abstract"
part is correct; the "imported" part may not be.)
compiler/intermod.m:
compiler/try_expand.m:
compiler/xml_documentation.m:
Conform to the change in hlds_module.m.
compiler/module_qual.m:
Update the documentation of the relationship of this module
with unused_imports.m.
compiler/hlds_data.m:
Document a problem with the status of instance definitions.
compiler/hlds_out_module.m:
Update the code that prints out the module_info to conform to the change
to hlds_module.m.
Print status information about instances, which was needed to diagnose
one of the bugs in unused_imports.m. Format the output for instances
nicer.
compiler/prog_item.m:
Add a convenience predicate.
compiler/prog_data.m:
Remove a type synonym that makes things harder to understand, not easier.
compiler/modules.m:
Delete an XXX that asks for the feature this diff implements.
Add another XXX about how that feature could be improved.
compiler/Mercury.options.m:
Add some more modules to the list of modules on which the compiler
should be invoked with --no-warn-unused-imports.
compiler/*.m:
library/*.m:
mdbcomp/*.m:
browser/*.m:
deep_profiler/*.m:
mfilterjavac/*.m:
Delete unneeded imports. Many of these shadow other imports, and some
are just plain unneeded, as shown by --warn-unused-imports. In a few
modules, there were a *lot* of unneeded imports, but most had just
one or two.
In a few cases, removing an import from a module, because it *itself*
does not need it, required adding that same import to those of its
submodules which *do* need it.
In a few cases, conform to other changes above.
tests/invalid/Mercury.options:
Test the generation of messages about import shadowing on the existing
import_in_parent.m test case (although it was also tested very thoroughly
when giving me the information needed for the deletion of all the
unneeded imports above).
tests/*/*.{m,*exp}:
Delete unneeded imports, and update any expected error messages
to expect the now-smaller line numbers.
Estimated hours taken: 3
Branches: main
Avoid some redundant work during determinism analysis. This diff speeds up
tools/speedtest by just shy of 0.7%.
compiler/det_analysis.m:
Instead of (a) getting a list of procedures in the module and then
(b) classifying them into three categories, do both jobs at once.
This avoids some redundant traversals and map lookups, and avoids
the creation of an intermediate data structure.
compiler/instmap.m:
Instead of converting a set into a list and iterating over that list
to check that elements of the set have a given property, iterate over
the set elements directly.
Put the arguments of a predicate in a more logical order.
compiler/det_util.m:
Conform to the change in instmap.m.
compiler/set_of_var.m:
Provide the all_true predicate needed by det_util.
library/*set*.m:
In every module that implements sets, provide an all_true predicate.
NEWS:
Mention the new predicates in the library.
Estimated hours taken: 8
Branches: main
compiler/inst_match.m:
Instead of first testing whether an inst exists in a set
and then inserting it if does not, use a single predicate
that does both the membership test and the insertion (if
the membership test failed) in one pass.
This speeds up compilation of one version of the rcpsp_cpx
stress test by about 9%, with negligible effect on tools/speedtest.
Some cleanups that should have been committed before this diff follow.
Change the structure of many of the predicates in this module from
containing multiple clauses, to a single clause with an explicit
disjunction, which (where relevant) now gets a require_comple_switch
wrapper. In several cases, this change has shown that we were
missing code for handling some kinds of insts. For example, some
predicates handled free/0 but not free/1, even though there was
no reason for the difference. This diff fixes such oversights
in places where the right action seems obvious to me, and adds
XXXs in places where I see no obvious fix.
Rename several predicates and function symbols to avoid ambiguities.
Add some XXXs on potential problems.
library/*set*.m:
Implement this insert_new predicate for all the implementations
of sets we have. The code in each case is copied from the code
of insert, with code to return a set unchanged replaced with `fail'.
NEWS:
Mention the new predicates.
Estimated hours taken: 12
Branches: main
Fix a performance problem in liveness. Liveness makes many calls to
divide_by_set, but the existing implementation of that predicate in
tree_bitset.m did not exploit the structure of its operands.
After this diff, it now does so, though not yet to the fullest extent
possible. However, even this is enough to reduce the time needed
to compile a variant of the zm_rcpsp_cpx.m stress test from 66 seconds
to 15, with liveness analysis no longer being the bottleneck.
On tools/speedtest, we get about a 0.4% speedup, which is just
above the noise threshold.
library/tree_bitset.m:
Specialize the implementation of divide_by_set for many of
the possible cases. Leave XXXs where further specialization
is possible.
Put some predicate definitions in a more logical order.
compiler/test_bitset.m:
This module has long been used (initially by Simon Taylor, later
by me) to test the correctness of the implementation of first
sparse_bitset.m and later tree_bitset.m. However, since it
slows down all set operations a lot (by doing them twice, once using
a bitset module and once using set_ordlist, and then comparing
the results), it is never enabled in production compilers,
and since it is usually not imported by any ordinary compiler
modules, it is rarely even compiled. It has thus tended to
get bitrot; changes in the set modules it uses need corresponding
changes in this module, but it has not been getting them.
To fix this, move this module from the compiler directory to the
library directory. By including the moved version in the library,
it will always be compiled, and anyone who breaks it will have
to fix the breakage before checking in their change.
The cost is about 16 kilobytes in the Mercury library's .so file,
which is well worth it.
library/test_bitset.m:
The moved module. It had to be updated to compile and work
with the current versions of tree_bitset.m and set_ordlist.m.
library/library.m:
Include the moved module in the library.
doc/Mmakefile:
Since the moved module is only for the implementors of the bitset
modules, do not include it in the documentation.
Sort the names of the modules that are not included in the
documentation.
tests/hard_coded/test_tree_bitset.{m,exp}:
Make this module, which tests the operation of tree_bitset.m,
both more thorough and more controllable.
Make it more thorough by testing it not just with some toy sets
and some small random sets as inputs, but also with some inputs
specifically designed to be stress tests. These are taken from
the old tree_bitset_difference test case.
Make it more thorough in another way by also testing the divide_by_set
operation.
Make it more controllable by making it easy to test just one operation
(for me now, that was of course divide_by_set), without the distraction
of outputs from tests of other operations.
tests/hard_coded/tree_bitset_tester.m:
This module used to do the job of test_bitset.m for test_tree_bitset.m.
This was needed while test_bitset.m was in the compiler directory,
but it is not needed now, and keeping it presents a double maintenance
problem. This diff therefore deletes it, and makes test_tree_bitset.m
use test_bitset.m from the library.
tests/hard_coded/tree_bitset_difference.{m,exp}:
Delete this test case. The stress test inputs it used to test the
difference operation with are now in test_tree_bitset.m, which
uses them to test not just the difference operation, but other
operations as well.
tests/hard_coded/test_bitset.{m,exp}:
Delete this test case, since it seems to be a duplicate of an early
version of tree_bitset_tester.m. Despite its name, it was NOT a copy
of the identically named module that used to be in the compiler
directory.
tests/hard_coded/Mmakefile:
Remove the now unneeded tree_bitset_difference and test_bitset
test cases from the list of test cases.
