compiler/ml_optimize.m:
After peephole optimization of a block, if the block consists only of
a single statement, then replace the block by the statement itself.
compiler/mlds_to_java_func.m:
Do not output curly brackets around an MLDS function body that is a block,
since that block will be output with its own curly brackets.
compiler/mlds.m:
Put the *type* of the pointer next to the *value* of the pointer.
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_optimize.m:
compiler/ml_rename_classes.m:
compiler/ml_string_switch.m:
compiler/ml_type_gen.m:
compiler/ml_unify_gen.m:
compiler/ml_unused_assign.m:
compiler/ml_util.m:
compiler/mlds_dump.m:
compiler/mlds_to_c_data.m:
compiler/mlds_to_cs.m:
compiler/mlds_to_java.m:
compiler/mlds_to_target_util.m:
compiler/rtti_to_mlds.m:
Conform to the change above.
compiler/mlds_dump.m:
New module to dump out MLDS code in a format suitable for debugging.
Unlike e.g. mlds_to_c_*.m, using the new module does not require
any setup, the generated output is not cluttered with rarely-relevant
details, and the format is clean, simple and direct.
compiler/ml_backend.m:
compiler/notes/compiler_design.html:
Add and document the new module.
compiler/ml_optimize.m:
Use the new module if the right compile-time flag is set.
(This is mostly needed so that we can import the new moule
without getting an unused import warning.)
compiler/mlds.m:
We used to have a function symbol ml_unop in the mlds_rval type
that applied one of four kinds of operations to an argument mlds_rval:
boxing, unboxing, casting or a standard unary operation, with a value
of type mlds_unary_op selecting between the four. Replace this system
with four separate function symbols in the mlds_rval type directly,
and delete the mlds_unary_op type.
The new arrangement requires fewer memory cells to be allocated,
and less indirection; it also leads to shorter and somewhat
more readable code.
compiler/ml_optimize.m:
Conform to the change above.
Recognize that a cast has negligible cost.
compiler/ml_code_util.m:
Conform to the change above.
Keep private a predicate that is not used by any other module,
after merging it with another previously-exported predicate
that only *it* uses.
Delete some other predicates that are not used anywhere.
compiler/ml_accurate_gc.m:
compiler/ml_call_gen.m:
compiler/ml_closure_gen.m:
compiler/ml_code_gen.m:
compiler/ml_disj_gen.m:
compiler/ml_elim_nested.m:
compiler/ml_foreign_proc_gen.m:
compiler/ml_global_data.m:
compiler/ml_lookup_switch.m:
compiler/ml_rename_classes.m:
compiler/ml_string_switch.m:
compiler/ml_tag_switch.m:
compiler/ml_unify_gen.m:
compiler/ml_unused_assign.m:
compiler/ml_util.m:
compiler/mlds_to_c.m:
compiler/mlds_to_cs.m:
compiler/mlds_to_java.m:
compiler/mlds_to_target_util.m:
compiler/rtti_to_mlds.m:
Conform to the change above.
At the moment, we tend not to generate such assignments, with the exception
of assignments to the MLDS versions of HLDS variables of dummy types.
The reason I am nevertheless adding this optimization is that I intend
to soon add code to ml_unify_gen.m that *will* generate assignments
to dead variables.
The idea is to optimize field updates involving packed arguments.
Given a type such as
:- type t
---> f(
f1 :: bool,
f2 :: bool,
f3 :: enum1,
f4 :: int
).
we currently implement a field update such as "T = T0 ^ f4 := 42",
whose HLDS representation is the two unifications
T0 = f(T0f1, T0f2, T0f3, _),
T = f(T0f1, T0f2, T0f3, 42)
using code that looks like this:
T0f1 = (T0[0] >> ...) & ...
T0f2 = (T0[0] >> ...) & ...
T0f3 = (T0[0] >> ...) & ...
T = allocate memory for new memory cell, put on primary tag
T[0] = (T0f1 << ...) | (T0f2 << ...) | (T0f3 << ...)
T[1] = 42
I want to implement it using code that looks like this:
T0w0 = T0[0]
T = allocate memory for new memory cell, put on primary tag
T[0] = T0w0
T[1] = 42
where T0w0 contains the entire first word of the memory cell of T0.
This code avoids a bunch of shifts, ORs and ANDs.
I propose to translate the T0 = f(T0f1, T0f2, T0f3, _) unification into
T0w0 = T0[0]
T0f1 = (T0[0] >> ...) & ...
T0f2 = (T0[0] >> ...) & ...
T0f3 = (T0[0] >> ...) & ...
while recording in the ml_gen_info/code_info that this *specific* packing of
T0f1, T0f2 and T0f3 is available in T0w0. When translating the following
unification, the code generator will see this, and this will allow it to
generate
T[0] = T0w0
instead of
T[0] = (T0f1 << ...) | (T0f2 << ...) | (T0f3 << ...)
However, by this time the assignments to T0f1, T0f2 and T0f3 have already
been generated. Whether or not they are dead assignments depends on whether
other code needs the values of those fields of T0. Deciding this
requires knowledge that the code generator can't have when translating
the deconstruction of T0. Hence the need for a new MLDS-to-MLDS optimization.
compiler/ml_unused_assign.m:
A new compiler module implementing the new optimization.
It is not part of ml_optimize.m because ml_optimize.m traverses
the MLDS forwards, while this optimization requires a backwards traversal:
you cannot know whether an assignment is dead unless you know that the
following code does not need the value of the variable it assigns to.
compiler/ml_backend.m:
compiler/notes/compiler_design.html:
Include the new module.
compiler/mlds.m:
The new optimization needs extra information about loops.
When it enters into the loop body, it knows which variables
are needed *after* the loop, but it does not know which variables
the loop body first reads and then writes. Without this knowledge,
it would optimize away assignments to loop control variables,
such as the increment of i in the loop
i = 0;
while (...) {
...; i = i+1; ...
}
Traditionally, compilers have solved this problem by doing fixpoint
iteration, adding to the live set at each program point until
no more additions are possible. We can do better, because we generate
loops in the MLDS in only two kinds of cases:
- loops implementing tail recursion, in which case the only extra
variables that we need to preserve assignments to in the loop body
are the input arguments of the procedure, and
- loops created by the compiler itself to loop over a set of alternatives,
for which the only extra variables that we need to preserve assignments
to in the loop body are the variables the compiler uses to control
the loop.
To make it possible for ml_unused_assign.m to do its job without
a fixpoint iteration, include in the MLDS representation of every
while loop a list of these variables.
Add a type to represent the identify of an MLDS local var,
for use by some of the modules below. They used to store this info
in the form of mlds_lvals, but that is not specific enough
to be used to fill in the new field in while loops.
compiler/ml_proc_gen.m:
Compute the information needed by the new pass, and invoke it
if the relevant option is set.
compiler/options.m:
Add this option. It is for developers only, so it is undocumented.
compiler/ml_util.m:
Add a utility function needed in several places.
compiler/ml_accurate_gc.m:
compiler/ml_disj_gen.m:
compiler/ml_elim_nested.m:
compiler/ml_lookup_switch.m:
compiler/ml_optimize.m:
compiler/ml_rename_classes.m:
compiler/ml_string_switch.m:
compiler/mlds_to_c.m:
compiler/mlds_to_cs.m:
compiler/mlds_to_java.m:
compiler/mlds_to_target_util.m:
Conform to the changes in mlds.m.
compiler/mlds.m:
Change the field of the new_object MLDS statement that deals with tags
from being a maybe(mlds_ptag) to being just an mlds_ptag.
This field is not actually used by any of mlds_to_{c,cs,java}.m.
It is used only by ml_accurate_gc.m, to decide whether to tag
a copied pointer. For that purpose, testing whether the ptag is zero
is just as easy as testing whether the maybe ptag is yes(...),
and ml_unify_gen.m used to set this field to yes(...) if and only if
the ptag was not zero anyway. The change allows the compiler to avoid
allocating a yes(...) cell for every new_object statement it generates.
Clarify a related comment.
compiler/ml_unify_gen.m:
Pass ptags instead of maybe ptags to the predicates that create new_object
statements. We can do this because we always know what ptag we are about to
put on the new object we are allocating. Setting MaybePtag to no
when Ptag was 0 was effectively forgetting this fact.
Not forgetting allows us to generate better code when generating code
for a unification involved in the LCMC optimization. If the functor
involved in the LCMC has primary tag 0, the address we compute
for the field to be filled in used to have a MaybePtag = no
in the first argument of the ml_field rval, which meant that
the primary tag had to be masked off at runtime. We now generate
an ml_field rval that has yes(0) as its first field, which tells the
runtime that the primary tags bits *don't* have to be masked off.
This is shown by this diff, from just before the call to qualify_inst
generated for the call to from qualify_mode in module_qual.qualify_items.m
- AddrInstB_40 = (MR_Word *) &(MR_hl_mask_field((MR_Word) *Mode_12,
(MR_Integer) 1));
+ AddrInstB_40 = (MR_Word *) &(MR_hl_field(MR_mktag(0), *Mode_12,
(MR_Integer) 1));
Reduce superficial differences between two pieces of code doing
very similar tasks, as a prelude to factoring them out.
compiler/ml_accurate_gc.m:
compiler/ml_elim_nested.m:
compiler/ml_optimize.m:
compiler/mlds_to_c.m:
compiler/mlds_to_cs.m:
compiler/mlds_to_java.m:
Conform to the change in mlds.m.
compiler/mlds.m:
Introduce the concept of typed rvals to the MLDS (it is already present
in the LLDS).
To start with, use typed rvals to represent the arguments of the new_object
operation.
compiler/ml_accurate_gc.m:
compiler/ml_closure_gen.m:
compiler/ml_elim_nested.m:
compiler/ml_optimize.m:
compiler/ml_rename_classes.m:
compiler/ml_unify_gen.m:
compiler/ml_util.m:
compiler/mlds_to_c.m:
compiler/mlds_to_cs.m:
compiler/mlds_to_java.m:
compiler/mlds_to_target_util.m:
Conform to the change in the new_object operation. In most places,
this means replacing two lists (one of rvals, and one of types)
that had to have the same length, with one list of typed rvals.
The use of typed rvals thus encodes a required invariant in the
type of the data, making its violation impossible. It also means
that many places that used to require iterating on two lists
simultaneously can be replaced by a simple iteration on one list only.
Now that we can optimize tail recursion for all MLDS targets better via
the MLDS code generator than via ml_tailcall.m, we don't need it anymore.
compiler/ml_tailcall.m:
Delete this module.
compiler/ml_backend.m:
compiler/notes/compiler_design.html:
Delete the inclusion and the documentation of the deleted module.
compiler/mark_tail_calls.m:
Update old references to the deleted module, as well as some comments.
compiler/mercury_compile_mlds_back_end.m:
Don't invoke the deleted module.
compiler/options.m:
Delete the (developer-only) options that used to control whether
we did tail call optimization (TCO) via ml_tailcall.m or not.
compiler/ml_optimize.m:
Delete the parts of this module that worked in concert with ml_tailcall.m
to implement TCO.
compiler/mlds.m:
Delete the field from ml_call_stmts that was needed only by ml_tailcall.m.
compiler/ml_call_gen.m:
Don't fill in the deleted field.
Shift here the only part of the old contents of ml_tailcall.m that is
still needed, the check for whether rvals would become dangling references
if we discarded the current call's stack frame.
compiler/ml_elim_nested.m:
Conform to the change to mlds.m, and eliminate an unused field
in elim_info.
compiler/ml_accurate_gc.m:
compiler/ml_code_util.m:
compiler/ml_commit_gen.m:
compiler/ml_proc_gen.m:
compiler/ml_rename_classes.m:
compiler/ml_util.m:
compiler/mlds_to_c.m:
compiler/mlds_to_cs.m:
compiler/mlds_to_java.m:
compiler/mlds_to_target_util.m:
Conform to the changes above.
compiler/mlds.m:
Delete the attribute field in MLDS function definitions, because
we have never used it.
compiler/mlds_to_c.m:
compiler/mlds_to_cs.m:
compiler/mlds_to_java.m:
Delete the code that ignored the attribute field in function definitions
*without* writing it out.
compiler/ml_proc_gen.m:
compiler/ml_type_gen.m:
Delete code that filled in this field.
compiler/ml_closure_gen.m:
compiler/ml_code_util.m:
compiler/ml_elim_nested.m:
compiler/ml_optimize.m:
compiler/ml_rename_classes.m:
compiler/ml_tailcall.m:
compiler/ml_util.m:
compiler/mlds_to_target_util.m:
Delete code that copied this field around.
Some global variables generated by the MLDS backend need to be visible
across module boundaries, and therefore mlds_data definitions, which
contained global as well as other variables, used to have their names
qualified; usually module-qualified, though sometimes type-qualified.
However, since the diff that partitioned mlds_data_defns into the
definitions of local variables, global variables and field variables,
the qualification of local variables has *not* been necessary, so this diff
removes such qualifications. This makes the MLDS code generating references
to local variables simpler, more readable, and slightly faster.
The generated code is also shorter and easier to read.
There are two exceptional cases in which local variables *did* need
qualification, both of which stretch the meaning of "local".
One such case is the "local" variable dummy_var, which (by definition)
is only ever assigned to, and never used. It is also never defined
in MLDS-generated code; instead, it is defined defined in private_builtin.m
(for the Java and C# backends) or the runtime (for C). All three backends
currently require references to this variable in the runtime to be module
qualified. There are three possible fixes to this problem, which is caused
by the fact that this "local" variable is in fact global.
- Fix 1a would be to make dummy_vars global, not local.
- Fix 1b is to special-case dummy_vars in mlds_to_{c,cs,java}.m, and put
the fixed "private_builtin" qualifier in front of it.
- Fix 1c would be to modify the compiler to never generate any references
to dummy vars at all.
This diff uses fix 1b, because it is simple. I (zs) will explore fix 1c
in the future, and see if it is viable.
The second such case occurs when generating code for unifications
involving function symbols represented by the addresses of reserved objects.
These addresses used to be represented as the addresses of mlds_data
definitions, then as addresses of field variables cast as qualified
local variables. Since diff this makes all local variables unqualified,
this can't continue. Two possible fixes are
- Fix 2a: introduce an mlds const rval representing the address of a field
variable, which solves the problem because unlike local variables,
field variables can still be either module- or type-qualified.
- Fix 2b: prohibit the use of the addresses of reserved objects as tags.
After a (short) discussion on m-dev, this diff uses fix 2b.
compiler/mlds.m:
Delete the qual_local_var_name type, and replace all its uses
with the mlds_local_var_name type. Delete the module qualifier field
in mlds_data_addr_local_var consts.
compiler/ml_code_util.m:
Simplify the predicates and functions whose task is to build references
to local variables. Delete the arguments that they don't need anymore.
Delete one function entirely, since calling it now takes both more
characters and more code than its shortened body does.
compiler/ml_accurate_gc.m:
compiler/ml_call_gen.m:
compiler/ml_closure_gen.m:
compiler/ml_code_gen.m:
compiler/ml_commit_gen.m:
compiler/ml_disj_gen.m:
compiler/ml_elim_nested.m:
compiler/ml_foreign_proc_gen.m:
compiler/ml_lookup_switch.m:
compiler/ml_optimize.m:
compiler/ml_rename_classes.m:
compiler/ml_string_switch.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:
compiler/rtti_to_mlds.m:
Conform to the changes above. Stop qualifying local variable names,
and stop passing the parameters that used to be used *only* for
qualifying local variable names.
compiler/mlds_to_c.m:
compiler/mlds_to_cs.m:
compiler/mlds_to_java.m:
Conform to the changes above, and implement fix 1b.
NEWS:
compiler/options.m:
compiler/make_tags.m:
Implement fix 2b by disabling the --num-reserved-objects option.
This ensures that we don't use the addresses of reserved objects as tags.
library/private_builtin.m:
Move the C# definition of dummy_var next to the Java definition,
and fix the comments on them.
This is a step towards implementing not just self- but also mutual
tail recursion in the MLDS code generator.
compiler/options.m:
Add an option, --optimize-tailcalls-codegen, that asks for MLDS backend
to optimize self tail calls via the code generator, not ml_tailcall.m.
(We still use ml_tailcall.m if the new option is not set.) The new option
is set by default, but this can be changed if we find a problem
with the new approach.
compiler/mark_tail_calls.m:
Fix a bug. In a disjunction, the nonlast disjuncts cannot contain tail
calls, because (a) if a nonlast disjunct is semidet, then after any
such recursive call fails, we can still backtrack to later disjuncts,
and (b) if the nonlast disjunct involved is det, the later disjuncts
should have been optimized away, and the disjunct wouldn't be nonlast
anymore.
Export predicates that allow the MLDS backend to mark tail calls
as *it* wants them marked.
Reorganize the predicates that generate warnings to make them useable
from the MLDS code generator as well, and export the required predicates.
(The MLDS code generator needs this access because in some cases,
a call that mark_tail_calls.m thinks is a tail call cannot be implemented
as such. Since only the MLDS code generator knows this fact, only *it*
can know when this warning may need to be generated.)
Some of the reorganization of code that generates warnings factors out
common code between mark_tail_calls.m and ml_tailcall.m.
compiler/ml_tailcall.m:
Export some functionality for the code generator to use.
Replace the found_recursive_call type, which used to be defined here,
with the found_any_rec_calls type from mark_tail_calls.m, since they
were isomorphic and had the same job.
Delete the code that was factored out into mark_tail_calls.m.
compiler/mercury_compile_mlds_back_end.m:
If --optimize-tailcalls-codegen is set, run the mark_tail_calls pass
before MLDS codegen.
Prepare for the code generator to generate warnings about calls that should
be tail calls not actually being tail calls.
Delete an unused exported predicate, and the imports it used to need.
compiler/mercury_compile_llds_back_end.m:
Fix style.
compiler/ml_gen_info.m:
Extend the code generator state with information needed for tail call
optimization, and for generating warnings.
compiler/ml_proc_gen.m:
When starting to generate code for a procedure, set up the new part
of the code generator state with the information needed to handle tail
calls, if we both (a) can optimize tail calls in the predicate, and (b)
we have been asked to.
After the code for the procedure body has been generated, *and* if
we have actually turned some tail calls into jumps to the start of
the procedure, create the wrapper around the MLDS code implementing
the body goal that makes such jumps possible.
compiler/ml_call_gen.m:
When generating code for a plain call, test whether it is a tail call,
and if so, try to optimize it. If we fail, generate a warning about
that fact, and fall back to generating code for it as we would do
for any non-tail call.
Provide mechanisms for this new code to compute the actual parameter
lvals for the input arguments of a (tail) call, since only these
have to be assigned from when replacing a tail call.
compiler/ml_code_util.m:
Provide mechanisms for ml_proc_gen to compute the mlds_arguments
of the formal parameters of just the input arguments of a procedure,
since only these have be assigned to when replacing a tail call.
(The predicates that perform these mirror image tasks should be
next to each other, perhaps in a new ml_args_util.m module.)
compiler/ml_closure_gen.m:
compiler/ml_code_gen.m:
compiler/ml_optimize.m:
Export to ml_call_gen.m (a slightly modified form of) a predicate
that is used in the replacement of tail calls.
Peephole optimization a pattern that we now generate.
compiler/rtti_to_mlds.m:
Conform to the changes above.
tests/hard_coded/semi_tail_call_in_nonlast_disjunct.{m,exp}:
Add a test case for the bug fixed in mark_tail_calls.m. Without the fix,
the updated MLDS code generator's output fails this test.
tests/hard_coded/Mmakefile:
Enable the new test case.
The first problem is that the MLDS constructs that defined functions and
the MLDS constructs that take the addresses of functions used different
data types to *name* those functions. The translations of these constructs
to each target language had to generate the same target language code,
but they did so via two (or in some cases more) separate pieces of code.
The second problem is that the MLDS functions that implement HLDS procedures,
and the auxiliary functions that are sometimes needed to help implement
those procedures, were not delineated as clearly as is they should be.
compiler/mlds.m:
To (mostly) fix the first problem, define the mlds_func_label type,
and use it to identify MLDS functions in both function definitions
and in the mlds_code_addr type that represents a reference to a function.
A full fix will require function definitions to use *qualified*
mlds_func_labels, as the mlds_code_addrs already do. However,
the problem that MLDS definitions are not qualified applies not just
to functions but to other entities as well, and is therefore better fixed
separately.
To fix the second problem, introduce the mlds_maybe_aux_func_id type.
This also addresses an old XXX by providing explicit ways to represent
gc trace functions for both auxiliary and non-auxiliary MLDS functions.
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_gen_info.m:
compiler/ml_optimize.m:
compiler/ml_proc_gen.m:
compiler/ml_rename_classes.m:
compiler/ml_tailcall.m:
compiler/ml_unify_gen.m:
compiler/ml_util.m:
compiler/mlds_to_c.m:
compiler/mlds_to_cs.m:
compiler/mlds_to_java.m:
compiler/mlds_to_target_util.m:
compiler/rtti_to_mlds.m:
Conform to the above.
This field of type maybe(mlds_rval) was *always* set to "no".
compiler/mlds.m:
As above.
compiler/ml_accurate_gc.m:
compiler/ml_call_gen.m:
compiler/ml_code_util.m:
compiler/ml_commit_gen.m:
compiler/ml_elim_nested.m:
compiler/ml_optimize.m:
compiler/ml_rename_classes.m:
compiler/ml_tailcall.m:
compiler/ml_util.m:
compiler/mlds_to_c.m:
compiler/mlds_to_cs.m:
compiler/mlds_to_java.m:
compiler/mlds_to_target_util.m:
Conform to the above.
This makes the generated MLDS code less cluttered and easier to work on.
compiler/ml_gen_info.m:
Add a field for recording whether the succeeded variable has been used.
compiler/ml_code_util.m:
Change the predicates that return references to the succeeded variable
to record that it has been used.
compiler/ml_call_gen.m:
compiler/ml_closure_gen.m:
compiler/ml_code_gen.m:
compiler/ml_commit_gen.m:
compiler/ml_disj_gen.m:
compiler/ml_foreign_proc_gen.m:
compiler/ml_lookup_switch.m:
compiler/ml_string_switch.m:
compiler/ml_unify_gen.m:
Use the updated forms of the predicates in ml_code_util.m.
compiler/ml_proc_gen.m:
Define the succeeded variable only if the new slot says it has been used.
compiler/ml_optimize.m:
Fix a bug triggered by the above change: when a tail recursive call
was the *entire body* of a MLDS function, ml_optimize.m did not find it,
and thus did not do the setup needed to prepare for the tail recursion.
Previously, the always-present declaration of "succeeded" made it
impossible for the tail call to be the only thing in the body.
An ml_stmt_block contains some definitions and some statements.
The definitions were traditionally stored in a single list of mlds_defns,
but lots of code knew that some kinds of mlds_defns just couldn't occur
in blocks. This diff, by storing the definitions of (a) local variables
and (b) continuation functions in separate field in ml_stmt_blocks,
gets the type system to enforce the invariant that other kinds of definitions
can't occur in blocks.
This also allows the compiler to do less work, since definitions
don't have to wrapped and then later unwrapped, and code that wants to look
at only e.g. the function definitions in a block don't have to traverse
the definitions of local variables (of which there are many more).
compiler/mlds.m:
Make the change described above.
compiler/ml_accurate_gc.m:
compiler/ml_call_gen.m:
compiler/ml_closure_gen.m:
compiler/ml_code_gen.m:
compiler/ml_code_util.m:
compiler/ml_commit_gen.m:
compiler/ml_disj_gen.m:
compiler/ml_elim_nested.m:
compiler/ml_lookup_switch.m:
compiler/ml_optimize.m:
compiler/ml_proc_gen.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_c.m:
compiler/mlds_to_cs.m:
compiler/mlds_to_java.m:
compiler/mlds_to_target_util.m:
Conform to the change above. This allows us to avoid lots of wrapping
up definitions.
In some cases, after this change, we don't need to process mlds_defns
*in general*, which leaves the predicates that used to do that,
and some of the predicates that they used to call, unused. Delete these.
In code that generated MLDS code, consistently use names containing
the word "Defn", instead of "Decl", for variables that contain
mlds_local_var_defns or mlds_function_defns. Some such predicates
generate lists of both local var definition and function definitions,
but most generate only one, and some generate neither.
compiler/mlds.m:
Make the change above.
compiler/ml_elim_nested.m:
compiler/ml_optimize.m:
compiler/ml_tailcall.m:
compiler/ml_type_gen.m:
compiler/ml_util.m:
compiler/mlds_to_c.m:
compiler/mlds_to_cs.m:
compiler/mlds_to_java.m:
compiler/mlds_to_target_util.m:
Conform to the change above.
compiler/mlds.m:
The flags field of the mlds_local_var_defn type was always set
to the same value, so it contained no information. Delete it.
(The field contained information in its original home in the
mlds_data_defn type; it distinguished local variables from
global and field variables.)
compiler/ml_code_util.m:
Delete the function that returned the value we always used to put
into the now-deleted field.
compiler/ml_elim_nested.m:
compiler/ml_optimize.m:
compiler/ml_util.m:
compiler/mlds_to_c.m:
compiler/mlds_to_cs.m:
compiler/mlds_to_java.m:
Conform to the changes above.
The MLDS either module- or type-qualifies several kinds of entities.
It used to use the same qual/3 wrapper for all these entities. However,
many kinds of entities are never (and can never be) type-qualified,
because they are not defined inside a type.
This diff replaces the mlds_fully_qualified_name type, and its qual/3 wrapper,
with a separate type and a separate wrapper for each kind of entity.
For those entities that can be both module- and type-qualified, have this
wrapper continue to include a mlds_qual_kind (module_qual or type_qual) field;
for the entities that are only ever module qualified, omit this field.
compiler/mlds.m:
Make the change described above.
There are some related changes.
The first is that the argument of the ml_field_named rval specifying
the field used to be a string. Change this to be a field_var_name,
because if a field's name is given by a field_var_name in its definition,
it should be given by that same field_var_name in its uses as well.
Without this, it is unnecessarily hard to ensure that the code that
generates the target language versions of the field's name match
in definitions and uses; specification, it would be unnecessarily hard
to ensure that they do module- or type-qualification the same way.
The second is required by the first. We used to use "ptr_num"
as the name of only a compiler-generated local variable, but it is
actually the name of a field in a compiler-generated class, and the
local variable use actually refers to the field. Therefore this diff
moves the reference to this from the mlds_local_var_name type
to the mlds_field_var_name type.
The third is switching to a more consistent naming scheme:
having the unqualified name of entities of kind xxx be mlds_xxx_name
and the qualified version of those names being qual_xxx_name.
compiler/ml_accurate_gc.m:
compiler/ml_call_gen.m:
compiler/ml_code_util.m:
compiler/ml_elim_nested.m:
compiler/ml_foreign_proc_gen.m:
compiler/ml_global_data.m:
compiler/ml_optimize.m:
compiler/ml_proc_gen.m:
compiler/ml_tailcall.m:
compiler/ml_type_gen.m:
compiler/ml_unify_gen.m:
compiler/ml_util.m:
compiler/mlds_to_c.m:
compiler/mlds_to_cs.m:
compiler/mlds_to_java.m:
compiler/rtti_to_mlds.m:
Conform to the changes above.
compiler/java_names.m:
Clarify a variable name.
We used to use mlds_data_defns to represent three related but nevertheless
distinct kinds of entities: global variables, local variables, and fields
in classes. This diff replaces the mlds_data_defn type with three separate
types: mlds_global_var_defn, mlds_local_var_defn and mlds_field_var_defn
respectively, with corresponding changes to related types, such as
mlds_data_name.
The global variables are completely separate from the other two kinds.
Local and field variables are *mostly* separate from each other, but they
are related in one way. When we flatten out nested functions, the child
nested function can no longer access its parent function's local variables,
so we pass those variables to it as fields of an environment structure.
This requires turning local variables to fields of that structure,
and the code in the flattened previously-nested function that accesses
those fields naturally wants to treat them as if they were local variables
(as indeed they sort-of were before the flattening). There are therefore
ways to convert each of local and fields vars into the other.
This restructuring makes clear several invariants of the MLDS we generate
that were previously hidden. For example, variables with certain kinds of
names (in the before-this-diff, general version of the mlds_var_name type)
could appear only as function arguments or as locals in ml_stmt_blocks,
not in ml_global_data, while for some other names the opposite was the case.
And in several cases, functions used to take a general mlds_data_defn
as argument but aborted if given the "wrong kind" of mlds_data_defn.
This diff also makes possible further simplifications. For example,
local vars should not need some flags (since e.g. they are never per-instance),
and should never need either module or type qualification, while global
variables (which are also never per-instance) should never need type
qualification (since they are not fields of a type). The definitions
in blocks should consist of local variables and (before flattening) functions,
not global variables, field variables or classes, while the members in classes
should be only field variables and functions (and maybe classes), not
global or local variables. Those changes will be in future diffs;
this is already large enough.
compiler/mlds.m:
Make the changes described above.
Use tighter types where possible.
Use (a generalized version) of the mlconst_named_const functor
to represent values of enum types defined in the runtimes
of the target platforms.
compiler/ml_global_data.m:
Store *only* global variables in fields that previously stored general
mlds_datas (that by design were always global).
Store *only* closure wrapper functions in the previous non-flat-defns
field. Before this diff, the code generator only put closure wrapper
functions in this field, but then ml_elim_nested.m put everything
resulting from the expansion of those functions back into those fields
as well, some of which were not functions. It now puts those non-function
things into the MLDS data structure directly.
compiler/ml_code_util.m:
compiler/ml_util.m:
Conform to the changes above.
Use tighter types where possible. If appropriate, change the name
of the function or predicate accordingly.
Represent references to enum constants defined in the runtime of the
target language as named constants (since they is what they are),
instead of representing them as MLDS "variables", which required
the code of mlds_to_cs.m had to special-case the treatment
of those "variables".
compiler/ml_elim_nested.m:
Conform to the changes above.
Use tighter types where possible.
Don't put the environment types resulting from flattening nested scopes
back into the non-flat-defns slot of the ml_elim_info; instead, return
them separately to code that puts them directly in the MLDS.
compiler/rtti.m:
When returning the names of enum constants in the C runtime, return also
the prefixes that you need to place in front of these to obtain their names
in the Java and C# runtimes.
compiler/mercury_compile_mlds_back_end.m:
compiler/ml_accurate_gc.m:
compiler/ml_call_gen.m:
compiler/ml_closure_gen.m:
compiler/ml_code_gen.m:
compiler/ml_commit_gen.m:
compiler/ml_disj_gen.m:
compiler/ml_foreign_proc_gen.m:
compiler/ml_gen_info.m:
compiler/ml_lookup_switch.m:
compiler/ml_optimize.m:
compiler/ml_proc_gen.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/mlds_to_c.m:
compiler/mlds_to_cs.m:
compiler/mlds_to_java.m:
compiler/mlds_to_target_util.m:
compiler/rtti_out.m:
compiler/rtti_to_mlds.m:
Conform to the changes above.
Move a utility function from ml_util.m to mlds_to_target_util.m,
since it is used only in mlds_to_*.m.
compiler/mlds.m:
The MLDS used to have two different ways to refer to scalar common
data structures. It had an rval for the *name* of the scalar common,
and an mlds_name for its *address*. The name could then be wrapped up
inside a mlconst_data_adr function symbol to convert it to rval.
An mlds_name is intended to be used for the names of data definitions
in the MLDS, but scalar commons were never defined in this way.
And the name and address of a scalar common differ in C only by
the addition of an "&" operator in front, so the fact that they
had to be processed by different code (due to them having different types)
*required* double maintenance.
This diff fixes this anomaly by making both the name and the address
of a scalar common its own specific function symbol in the mlds_rval type.
They differ in the presence or absence of an "_addr" suffix.
Since all references to a vector common are to its address, give
the existing mlds_rval function symbol for vector commons the "_addr
suffix as well, for consistency.
Replace the general mlconst_data_addr function symbol in the
mlds_rval_const with its remaining instances. This allows the code
constructing them to be smaller and simpler, and enables them
to be treated differently in the future, if needed.
compiler/mlds_to_c.m:
compiler/mlds_to_cs.m:
compiler/mlds_to_java.m:
Conform to the changes in mlds.m.
Put the code translating the various common structures next to each other,
where they werent' before. Add XXXs about the differences between them
that are probably unnecessary and may possibly be latent problems.
compiler/ml_util.m:
Conform to the changes in mlds.m.
Change the interface to a set of predicates that looks for variables
inside various MLDS constructs to take a variable name, not a data name,
as the thing being looked for.
compiler/ml_closure_gen.m:
compiler/ml_code_util.m:
compiler/ml_elim_nested.m:
compiler/ml_global_data.m:
compiler/ml_optimize.m:
compiler/ml_proc_gen.m:
compiler/ml_string_switch.m:
compiler/ml_tailcall.m:
compiler/ml_unify_gen.m:
compiler/mlds_to_target_util.m:
compiler/rtti_to_mlds.m:
Conform to the changes in mlds.m, and maybe ml_util.m.
In ml_proc_gen.m, put related arguments of some predicates and functions
next to each other.
compiler/mlds.m:
This diff fixes two minor annoyances imposed by the old use of the
mlds_context type in the MLDS.
The first annoyance was that the mlds_context type used to be an
abstract type that was privately defined to be a trivial wrapper
around a prog_context. It had the exact same information content
as a prog_context, but you had to go through translation functions
to translate prog_contexts to mlds_contexts and vice versa.
I think Fergus's idea was that we may want to add other information
to the mlds_context type. However, since we haven't felt the need
to anything like that in the 18 years (almost to the day) that the
mlds_context type existed, I think this turned out to be a classic
case of YAGNI (you ain't gonna need it).
This diff deletes the mlds_context type, and replaces its uses
with prog_context.
The second annoyance was that actual MLDS code, i.e. values of the
mlds_stmt type, always had to wrapped up inside a term of the statement
type, a term which paired a context with the mlds_stmt.
This diff moves the context information (now prog_context, not
mlds_context) into each function symbol of the mlds_stmt type,
deletes the statement type, and replaces its uses with the now-expanded
mlds_stmt type. This simplifies most code that deals with MLDS code.
compiler/ml_util.m:
Add a function, get_mlds_stmt_context, for the (very rare) occasions
where we want to know the context of an mlds_stmt *before* testing
to see what function symbol it is bound to.
compiler/ml_accurate_gc.m:
compiler/ml_call_gen.m:
compiler/ml_closure_gen.m:
compiler/ml_code_gen.m:
compiler/ml_code_util.m:
compiler/ml_commit_gen.m:
compiler/ml_disj_gen.m:
compiler/ml_elim_nested.m:
compiler/ml_foreign_proc_gen.m:
compiler/ml_global_data.m:
compiler/ml_lookup_switch.m:
compiler/ml_optimize.m:
compiler/ml_proc_gen.m:
compiler/ml_simplify_switch.m:
compiler/ml_string_switch.m:
compiler/ml_switch_gen.m:
compiler/ml_tag_switch.m:
compiler/ml_tailcall.m:
compiler/ml_type_gen.m:
compiler/ml_unify_gen.m:
compiler/mlds_to_c.m:
compiler/mlds_to_cs.m:
compiler/mlds_to_java.m:
compiler/rtti_to_mlds.m:
Conform to the changes above.
In some cases, a function was given two separate contexts, sometimes from
two separate sources; a prog_context and an mlds_context. In such cases,
keep only one source.
Standardize on Stmt as the variable name for "statement".
Delete redundant $module references from unexpected and other abort
predicates.
In one case, delete a function that was a duplicate of another function.
Give some predicates and functions more meaningful names.
compiler/mlds.m:
Change the target_code_entity_name target code component to
target_code_function_name, since we only ever put function names into it.
(Two pieces of code used to process data names and class names inside
target_code_entity_names, but these never had anything to process.)
compiler/ml_util.m:
Delete the defn_entity_name utility predicate, to force the recoding
of its call sites to test the kind of a *definition*, not the kind of
a *definition's name*.
Delete the defn_context utility predicate, since it isn't needed anymore.
Change tests for different kinds of definitions to return the specialized
(data, function or class) form of the definition, if relevant, to allow
the caller to use that form instead.
compiler/ml_elim_nested.m:
compiler/ml_foreign_proc_gen.m:
compiler/ml_optimize.m:
compiler/ml_tailcall.m:
compiler/mlds_to_c.m:
compiler/mlds_to_cs.m:
compiler/mlds_to_java.m:
Conform to the above, and avoid using mlds_entity_names in other ways
as well.
compiler/mlds.m:
Make type of the name of an mlds_function_defn not an mlds_entity_name,
but a bespoke type, mlds_function_name. To make this possible, create
the mlds_function_name type. This step also documents the fact that
the old entity_export names always applied to function definitions.
Make type of the name of an mlds_class_defn not an mlds_entity_name,
but a bespoke type, mlds_function_name. To make this possible, create
the mlds_type_name type. (The MLDS backend refers to mlds_class_defns
sometimes as "classes" and sometimes as "types"; when it handles
their names, it mostly uses the "type" terminology.)
compiler/ml_code_util.m:
compiler/ml_elim_nested.m:
compiler/ml_foreign_proc_gen.m:
compiler/ml_global_data.m:
compiler/ml_optimize.m:
compiler/ml_proc_gen.m:
compiler/ml_tailcall.m:
compiler/ml_type_gen.m:
compiler/ml_unify_gen.m:
compiler/ml_util.m:
compiler/mlds_to_c.m:
compiler/mlds_to_cs.m:
compiler/mlds_to_java.m:
compiler/mlds_to_target_util.m:
Conform to the above: stop wrapping and unwrapping data names.
In a few places, do some other cleanups.
compiler/mlds.m:
Make type of the name of an mlds_data_defn not an mlds_entity_name,
but an mlds_data_name, one of the several possibilities that
mlds_entity_name chooses amongst. For data definitions, we always
use a data name.
compiler/ml_code_util.m:
compiler/ml_elim_nested.m:
compiler/ml_global_data.m:
compiler/ml_optimize.m:
compiler/ml_proc_gen.m:
compiler/ml_type_gen.m:
compiler/ml_util.m:
compiler/mlds_to_c.m:
compiler/mlds_to_cs.m:
compiler/mlds_to_java.m:
compiler/rtti_to_mlds.m:
Conform to the above: stop wrapping and unwrapping data names.
Until now, we used a single type, mlds_defn, to contain both
- generic information that we need for all MLDS definitions, such as
name and context, and
- information that is specific to each different kind of MLDS definition,
such as a variable's initializer or a function's list of parameter types.
The former were contained in three fields in the mlds_defns directly,
while the latter were contained in a fourth field that was a discriminated
union of mlds_data_defn, mlds_function_defn and mlds_class_defn.
While seemingly parsimonious, this design meant that if we had e.g. a list
of variable definitions, we would have to wrap the mlds_defn/4 wrapper around
them to give them their names, and thereafter, any code that processed
that list would have to be prepared to process not just variables but also
functions and classes.
This diff moves the three generic fields into each of the mlds_data_defn,
mlds_function_defn and mlds_class_defn types, making each those types
self-contained, and leaving mlds_defn as nothing more than a discriminated
union of those types.
In the few places that want to look at the generic fields *without*
caring about what kind of entity is being defined, this design requires
a bit of extra work compared to the old design, but in many other places,
the new design allows us to return mlds_data_defns, mlds_function_defns
or mlds_class_defns instead of just mlds_defns.
compiler/mlds.m:
Make the change described above.
Store type definions (for high level data) and table structures definitions
separately from other definitions in the MLDS type, since we can now
give them tighter types.
compiler/ml_global_data.m:
Change the fields that store flat cells from storing mlds_defns to
storing mlds_data_defns, since we can now do so.
Add an XXX about an obsolete comment.
compiler/mercury_compile_mlds_back_end.m:
compiler/ml_accurate_gc.m:
compiler/ml_call_gen.m:
compiler/ml_closure_gen.m:
compiler/ml_code_gen.m:
compiler/ml_code_util.m:
compiler/ml_commit_gen.m:
compiler/ml_disj_gen.m:
compiler/ml_elim_nested.m:
compiler/ml_foreign_proc_gen.m:
compiler/ml_gen_info.m:
compiler/ml_lookup_switch.m:
compiler/ml_optimize.m:
compiler/ml_proc_gen.m:
compiler/ml_string_switch.m:
compiler/ml_switch_gen.m:
compiler/ml_tailcall.m:
compiler/ml_type_gen.m:
compiler/ml_util.m:
compiler/mlds_to_c.m:
compiler/mlds_to_cs.m:
compiler/mlds_to_java.m:
compiler/rtti_to_mlds.m:
Conform to the changes above. Where possible with only local changes,
return mlds_data_defns mlds_function_defns or mlds_class_defns instead
of just mlds_defns. Put the mlds_data(_), mlds_function(_) or mlds_class(_)
wrapper around those definitions as late as possible (typically, when
our current code wants to put it into the same list as some other kind
of definition), in the hope that in the future, that wrapping can be
delayed even later, or even avoided altogether. Make the places where
such improvements may be possible with "XXX MLDS_DEFN".
In some places, the tighter data representation allows us to *delete*
"XXX MLDS_DEFN" markers.
Move some common code from mlds_to_{cs,java}.m to ml_util.m.
In mlds_to_{cs,java}.m, add prefixes to the function symbols in a type
to reduce ambiguity.
compiler/mlds.m:
The mlds_defn type can store the definition of a piece of data,
a function, or a class. The information contained in the definition
of a class was stored in a separate type, but the information stored
in the other two kinds of definitions weren't, which made it impossible
to store e.g. a list of just *data* definitions. Fix this by providing
two types that store the information contains in data and function
definitions respectively.
compiler/ml_code_util.m:
compiler/ml_elim_nested.m:
compiler/ml_global_data.m:
compiler/ml_optimize.m:
compiler/ml_proc_gen.m:
compiler/ml_tailcall.m:
compiler/ml_type_gen.m:
compiler/ml_util.m:
compiler/mlds_to_c.m:
compiler/mlds_to_cs.m:
compiler/mlds_to_java.m:
compiler/rtti_to_mlds.m:
Conform to the change above.
compiler/mlds.m:
Replace the old definition of mlds_var_name, which was a string
with an optional integer. The integer was intended to be the number
of a HLDS variable, while auxiliary variables created by the compiler,
which do not correspond to a HLDS variable, would not have the optional
integer.
This design has a couple of minor problems. The first is that there is
no place in the compiler where all the variable names are visible at once,
and without such a place, we cannot be sure that two names constructed
for different purposes don't accidentally end up with the same name.
The probability of such a clash used to be astronomically small
(which is why this hasn't been a problem), but it was not zero.
The second problem is that several kinds of compiler-created MLDS variables
want to have numerical suffixes too, usually with the suffix being a
unique sequence number used as a means of disambiguation. Most of the
places where these were created put the numerical suffix into the name
string itself, while some put the sequence number as the optional integer.
As it happens, neither of those actions is good when one wants to take
the independently generated MLDS code of several procedures in an SCC
and merge them into a single piece of MLDS code. For this, we want to
rename apart both the HLDS variable numbers and the sequence numbers.
Having the sequence number baked into the strings themselves obviously
makes such renumbering unnecessarily hard, while having sequence numbers
in the slots intended for HLDS variable numbers makes the job impossible
to do safely.
This diff switches to a new representation of mlds_var_names that
has a separate function symbol for each different "origin story"
that is possible for MLDS variables. This addresses both problems.
The single predicate that converts this structured representation
to a string is the place where we can ensure that two semantically
different MLDS variables never get translated to the same string.
The current version of this predicate does *not* offer this guarantee,
but later versions could.
And having all the integers used in mlds_var_names for different purposes
stored as arguments of different function symbols (that clearly indicate
their meaning) makes it possible to rename apart different sets
of MLDS variables easily and reliably.
Move the code for converting mlds_var_names from ml_code_util.m to here,
to make it easier to maintain it together with the mlds_var_name type.
compiler/ml_code_util.m:
Conform to the above change by generating structured MLDS var names.
Delete a predicate that is not needed with structured var names.
Delete the code moved to mlds.m.
Delete a predicate that has been unused since we deleted the IL backend.
Add ml_make_boxed_type as a version of ml_make_boxed_types that returns
exactly one type. This simplifies some code elsewhere.
Add "hld" to some predicate names to make clear that they are intended
for use only with --high-level-data.
compiler/ml_type_gen.m:
Conform to the above change by generating structured MLDS var names.
Add "hld" to the names of the (many) predicates here that are used
only with --high-level-data to make clear that fact.
compiler/mlds_to_cs.m:
compiler/mlds_to_java.m:
Conform to the above change by generating structured MLDS var names.
Add a "for_csharp" or "for_java" suffix to some predicate names
to avoid ambiguities.
compiler/ml_accurate_gc.m:
compiler/ml_call_gen.m:
compiler/ml_closure_gen.m:
compiler/ml_commit_gen.m:
compiler/ml_disj_gen.m:
compiler/ml_elim_nested.m:
compiler/ml_foreign_proc_gen.m:
compiler/ml_gen_info.m:
compiler/ml_global_data.m:
compiler/ml_lookup_switch.m:
compiler/ml_optimize.m:
compiler/ml_string_switch.m:
compiler/ml_unify_gen.m:
compiler/ml_util.m:
compiler/mlds_to_c.m:
Conform to the above change by generating structured MLDS var names.
compiler/prog_type.m:
Add var_to_type, as a version of var_list_to_type_list that returns
exactly one type. This simplifies some code elsewhere.
compiler/java_names.m:
Give some predicates and functions better names.
compiler/ml_code_gen.m:
Fix typo.
The mlds_argument type describes an argument of an MLDS function: its name,
its type and information about how to trace it for accurate gc. However,
it represented the argument name as an entity name, so the representation
in theory allowed the argument name *itself* to be a type, a function,
the name of a global variable holding rtti information etc. However, the
only kind of entity name that ever made sense is a variable name, and there
were some places in the compiler that threw an exception if they found
the argument name to be any kind of entity name other than a variable name.
compiler/mlds.m:
Change the representation of the name in each mlds_argument
from an entity name to a variable name.
compiler/ml_call_gen.m:
compiler/ml_closure_gen.m:
compiler/ml_code_util.m:
compiler/ml_elim_nested.m:
compiler/ml_optimize.m:
compiler/ml_tailcall.m:
compiler/ml_type_gen.m:
compiler/mlds_to_c.m:
Conform to the change above. Mostly this is by using VarNames directly,
not wrapping them up as entity_data(mlds_data_var(VarName)).
In several places, it is by not having to remove this wrapping.
And in a few places, it is by adding the wrapping back, to allow
interfacing to code that has good reason to expect entity names.
compiler/mlds_to_cs.m:
compiler/mlds_to_java.m:
As above, but additionally, rename some predicates involved in handling
entity and variable names.
For predicates that used to have different definitions but identical names
in these two files, give them a "for_csharp" or "for_java" suffix
to avoid the ambiguity, and thus make tags files work better.
Convert some related predicates from clauses to explicit disjunctions.
compiler/mlds.m:
Add a field to call statements in MLDS that contains a (probably empty)
set of markers. At the moment, the only marker possible is one that says
"don't generate a non-tail recursive call warning for this call".
compiler/ml_gen_info.m:
Add a field to the ml_gen_info type, which contains the state of the
MLDS code generator, that records the set of warnings that are disabled
for the HLDS goal currently being translated.
compiler/ml_code_gen.m:
When processing the subgoal inside a disable_warnings scope,
add the warnings disabled by the scope to the new field
in the ml_gen_info.
compiler/ml_call_gen.m:
When creating MLDS call statements, put the new marker in the call's new
field if goal_warning_non_tail_recursive_calls is among the currently
disabled warnings.
compiler/ml_tailcall.m:
Don't generate warnings about a recursive call not being *tail* recursive
if the call has the new marker.
compiler/ml_accurate_gc.m:
compiler/ml_code_util.m:
compiler/ml_commit_gen.m:
compiler/ml_elim_nested.m:
compiler/ml_optimize.m:
compiler/ml_util.m:
compiler/mlds_to_c.m:
compiler/mlds_to_cs.m:
compiler/mlds_to_java.m:
Conform to the changes above.
compiler/ml_optimize.m:
Move the call_optimize_tailcall predicate here, since it is called
only from this module. Give it a name that better describes its job,
and improve its documentation.
compiler/ml_util.m:
Give the call_is_recursive predicate a more precise (and non-leading)
name. Change its interface to avoid redundant tests in both this predicate
and its callers (of whether the MLDS statement is a call, and of whether
its callee is a constant code address), and also to avoid requiring
its callers to construct a module qualified name.
compiler/ml_tailcall.m:
Conform to the above changes.
compiler/ml_optimize.m:
Replace semidet disjunctions with require_complete_switch scopes,
with some switch arms being `fail'. This should allow us to optimize
some MLDS code we previously didn't, because the disjunctions weren't
updated when static common data structures were added to the MLDS.
Replace some multi-clause definitions with explicit disjunctions
for better readability.
Delete some obsolete comments. Fix the grammar in some other comments.
Add new predicates and functions take_while and drop_while to the list
module.
Deprecate takewhile/4, replacing it with take_while/4.
library/list.m:
As above.
NEWS:
Announce this change.
browser/parse.m:
compiler/compute_grade.m:
compiler/deforest.m:
compiler/mercury_compile_main.m:
compiler/ml_optimize.m:
compiler/mode_robdd.equiv_vars.m:
compiler/options_file.m:
compiler/structure_reuse.direct.choose_reuse.m:
compiler/structure_reuse.domain.m:
compiler/structure_sharing.domain.m:
compiler/term_constr_data.m:
compiler/write_deps_file.m:
compiler/xml_documentation.m:
deep_profiler/read_profile.m:
deep_profiler/top_procs.m:
library/list.m:
Conform to above changes.
This patch allows the pragma to be parsed, and records the information from
the pragma in the proc_info structure for the relevant procedures.
The patch uses the pragma for the MLDS backend. However because mutual
recursion is not yet supported on the MLDS backend, mutually recursive calls
are ignored by the pragma.
The patch also documents the pragma in the reference manual, this
documentation is commented out until it is implemented for both LLDS and
MLDS backends.
The patch does not implement the SCC feature discussed on the mailing list.
That can be added later.
compiler/prog_data.m:
compiler/prog_item.m:
Add new require_tail_recursion pragma.
compiler/prog_io_pragma.m:
Parse the new pragma.
Remove the arity_and_modes type and use pred_name_arity_mpf_mmode
type from prog_item.m
compiler/parse_tree_out_pragma.m:
Support pretty printing the new pragma.
compiler/hlds_pred.m:
Add require_tailrec_info to the proc_info structure.
compiler/add_pragma.m:
Add information from the pragma to the proc_info structure after
parsing.
compiler/compiler_util.m:
Add a general warning_or_error type.
compiler/mlds.m:
Add require_tailrec_info to MLDS functions.
compiler/ml_proc_gen.m:
Copy the require_tailrec_info information from the HLDS to the MLDS.
compiler/ml_tailcall.m:
Generate errors and warnings with respect to the require_tail_recursion
pragma.
compiler/mercury_compile.m:
compiler/mercury_compile_mlds_back_end.m:
Return errors from the MLDS tailcall optimisation pass.
compiler/add_pragma.m:
compiler/comp_unit_interface.m:
compiler/equiv_type.m:
compiler/get_dependencies.m:
compiler/item_util.m:
compiler/make_hlds_separate_items.m:
compiler/module_qual.qual_errors.m:
compiler/module_qual.qualify_items.m:
compiler/prog_item_stats.m:
compiler/recompilation.version.m:
compiler/write_module_interface_files.m:
Conform to changes in prog_item.m.
compiler/ml_code_util.m:
compiler/ml_elim_nested.m:
compiler/ml_optimize.m:
compiler/ml_type_gen.m:
compiler/ml_util.m:
compiler/mlds_to_c.m:
compiler/mlds_to_cs.m:
compiler/mlds_to_java.m:
Conform to changes in mlds.m.
doc/reference_manual.texi
Document the require_tail_recursion pragma
tests/invalid/Mercury.options:
tests/invalid/Mmakefile:
tests/invalid/require_tail_recursion.err_exp:
tests/invalid/require_tail_recursion.m:
Add require_tail_recursion test case
Packages are modules whose only job is to serve as a container for submodules.
Modules like top_level.m, hlds.m, parse_tree.m and ll_backend.m are packages
in this (informal) sense.
Besides the include_module declarations for their submodules, most of the
packages in the compiler used to import some modules, mostly other packages
whose component modules their submodules may need. For example, ll_backend.m
used to import parse_tree.m. This meant that modules in the ll_backend package
did not have to import parse_tree.m before importing modules in the parse_tree
package.
However, this had a price. When we add a new module to the parse_tree package,
parse_tree.int would change, and this would require the recompilation of ALL
the modules in the ll_backend package, even the ones that did NOT import ANY
of the modules in the parse_tree package.
This happened even at one remove. Pretty much all modules in every one
of the backend have to import one or more modules in the hlds package,
and they therefore have import hlds.m. Since hlds.m imported transform_hlds.m,
any addition of a new middle pass to the transform_hlds package required
the recompilation of all backend modules, even in the usual case of the two
having nothing to do with each other.
This diff removes all import_module declarations from the packages,
and replaces them with import_module declarations in the modules that need
them. This includes only a SUBSET of their child modules and of the non-child
modules that import them.
compiler/mlds_to_il.m:
compiler/mlds_to_ilasm.m:
compiler/mlds_to_managed.m:
compiler/il_peephole.m:
compiler/ilasm.m:
compiler/ilds.m:
Delete the modules making up the MLDS->IL code generator.
compiler/globals.m:
compiler/prog_data.m:
Delete IL as a target and foreign language.
compiler/prog_io_pragma.m:
Delete the max_stack_size/1 foreign proc attribute. This was only
ever required by the IL backend.
compiler/options.m
Delete options used for the IL backend.
compiler/write_deps_file.m:
Don't generate mmake targets for .il files etc.
compiler/*.m:
Conform to the above changes.
compiler/notes/compiler_design.html
compiler/notes/work_in_progress.html
Conform to the above changes.
library/*.m:
Delete IL foreign_proc and foreign_export pragmas.
README.DotNet:
Delete this file.
browser/Mmakefile:
compiler/Mmakefile:
deep_profiler/Mmakefile:
mdbcomp/Mmakefile:
mfilterjavac/Mmakefile:
profiler/Mmakefile:
runtime/Mmakefile:
slice/Mmakefile:
Conform the above changes.
configure.ac:
Don't check that IL is a supported foreign language when performing the
up-to-date check.
Delete the '--enable-dotnet-grades' option.
scripts/Mmake.vars.in:
Delete variables used for the IL backend (and in on case by the Aditi
backend).
scripts/Mercury.config.bootstrap.in:
scripts/Mercury.config.in:
scripts/Mmake.rules:
scripts/canonical_grade.sh-subr:
tools/bootcheck:
Delete stuff related to the 'il' and 'ilc' grades.
doc/reference_manual.texi:
Delete the documentation of the 'max_stack_size' option.
doc/user_guide.texi:
Delete stuff related to the IL backend.
tests/hard_coded/csharp_test.{m,exp}:
tests/invalid/foreign_type_missing.{m,err_exp}:
tests/valid/csharp_hello.m:
Delete these tests: they are no longer relevant.
tests/hard_coded/equality_pred_which_requires_boxing.m:
tests/hard_coded/foreign_import_module.m:
tests/hard_coded/foreign_import_module_2.m:
tests/hard_coded/foreign_type.m:
tests/hard_coded/foreign_type2.m:
tests/hard_coded/foreign_type3.m:
tests/hard_coded/intermod_foreign_type2.m:
tests/hard_coded/lp.m:
tests/hard_coded/user_compare.m:
tests/invalid/foreign_type_2.m:
tests/invalid/foreign_type_missing.{m,err_exp}:
tests/invalid/foreign_type_visibility.m:
tests/invalid/illtyped_compare.{m,err_exp}:
tests/submodules/external_unification_pred.m
tests/valid/big_foreign_type.m
tests/valid/solver_type_bug.m
tests/valid_seq/foreign_type_spec.m
tests/valid_seq/intermod_impure2.m
Delete IL foreign_procs where necessary.
tests/hard_coded/Mmakefile
tests/invalid/Mercury.options
tests/invalid/Mmakefile
tests/submodules/Mmakefile
tests/valid/Mercury.options
tests/valid/Mmake.valid.common
tests/valid/Mmakefile
tests/valid_seq/Mmakefile
tests/valid_seq/Mercury.options
Conform to the above changes.
The code we emit to decide which arm of the switch is selected looks like this:
case_num = -1;
switch (MR_nth_code_unit(switchvar, 0)) {
case '98':
switch (MR_nth_code_unit(switchvar, 1)) {
case '99':
if (MR_offset_streq(2, switchvar, "abc"))
case_num = 0;
break;
case '100':
if (MR_offset_streq(2, switchvar, "aceg"))
case_num = 1;
break;
}
break;
case '99':
if (MR_offset_streq(2, switchvar, "bbb"))
case_num = 2;
break;
}
The part that acts on this will look like this for lookup switches:
if (case_num < 0)
succeeded = MR_FALSE;
else {
outvar1 = vector_common[case_num].f1;
...
outvarn = vector_common[case_num].fn;
succeeded = MR_TRUE;
}
and like this for non-lookup switches:
switch (case_num) {
case 0:
<code for case 0>
break;
...
case n:
<code for case n>
break;
default: /* if the switch is can_fail */
<code for failure>
break;
}
compiler/ml_string_switch.m:
Implement both non-lookup and lookup string switches via tries,
along the lines shown above.
compiler/ml_switch_gen.m:
Invoke the predicates that implement string switches via tries
in the circumstances in which option values call for them.
For now, we generate tries only for the C backend. Once the
problems identified for mlds_to_{cs,java,managed} below are fixed,
we can enable them on those backends as well.
compiler/options.m:
doc/user_guide.texi:
Add an option that governs the minimum size of trie switches.
compiler/ml_lookup_switch.m:
Factor out the code common to the implementation of all model-non
lookup switches, both in ml_lookup_switch.m and ml_string_switch.m,
and put it all into a new exported predicate.
The previously existing MLDS implementation methods for lookup switches
all build their lookup tables from maps that maps each cons_id
in the switch cases to the values of the output arguments of those cases.
For switch cases that apply to more than one cons_id, this map had
one entry for each of those cons_ids. For tries, we need a map
from *case ids*, not *cons ids* to the outputs. Since it is
easier to convert the one-to-one case_id->outputs map to the
many-to-one cons_id->outputs map than vice versa, change the
main data structure from which lookup tables are built to store data
in a case_id->outputs format, and provide predicates for its conversion
to the other (previously the only) format.
Rename ml_gen_lookup_switch to ml_gen_atomic_lookup_swith to distinguish
it from other predicates that also generate (other kinds of) lookup
switches.
compiler/switch_util.m:
Have the types representating lookup tables represent their contents
as a map, not as the assoc list derived from the map. Previously,
we didn't do anything with the map other than flatten it to the assoc list,
but for the MLDS backend, we may now also need to convert it to another
form of map (see immediately above).
compiler/builtin_ops.m:
Add two new builtin ops. The first, string_unsafe_index_code_unit,
returns the nth code unit in a string; the second, offset_str_eq,
does a string equality test on the nth and later code units of
two strings. They are used in the implementation of tries.
compiler/c_util.m:
Add a new binop category for each new binop, since they are not like
existing binops.
Put some existing binops into their own categories as well, since
bundling them with the other ops they were bundled with seems like
a bad idea.
compiler/hlds_goal.m:
Make the identifier of switch arms in tagged_cases a separate type
from int.
compiler/mlds_to_c.m:
compiler/llds_out_data.m:
Handle the new kinds of binops.
When writing out binop expressions, we used to do a switch on the binop
to get its category, and then another switch on the category. We now
switch on the binop directory, since this much harder to write out
code using new binops badly, and should be faster to boot.
In mlds_to_c.m, also make some cosmetic changes to the output to make it
easier to read, and thus to debug.
compiler/mlds_to_il.m:
Handle the new kinds of binops.
compiler/mlds_to_cs.m:
compiler/mlds_to_java.m:
compiler/mlds_to_managed.m:
Do not handle the new kinds of binops, since doing so would require
changing the whole approach of how these modules handle binops.
Clean up some predicates.
compiler/bytecode.m:
compiler/erl_call_gen.m:
compiler/lookup_switch.m:
compiler/ml_global_data.m:
compiler/ml_optimize.m:
compiler/ml_tag_switch.m:
compiler/opt_debug.m:
compiler/string_switch.m:
Conform to the changes above.
compiler/ml_code_gen.m:
Put the predicates of this module into a consistent order.
library/string.m:
Fix white space.
runtime/mercury_string.h:
Add a macro for each of the two new builtin operations.
mdbcomp/sym_name.m:
New module, containing the part of the old prim_data.m that
dealt with sym_names.
mdbcomp/builtin_modules.m:
New module, containing the part of the old prim_data.m that
dealt with builtin modules.
mdbcomp/prim_data.m:
Remove the things that are now in the two new modules.
mdbcomp/mdbcomp.m:
deep_proiler/Mmakefile:
slice/Mmakefile:
Add the two new modules.
browser/*.m:
compiler/*.m:
deep_proiler/*.m:
mdbcomp/*.m:
slice/*.m:
Conform to the above changes.
