Another step towards RTTI in Mercury.

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Another step towards RTTI in Mercury.

This step redefines the representation of type_ctor_infos inside the compiler
to be identical to the representation we will need for efficient interpretation
of RTTI data structures in Mercury, following on from an earlier step which
did the same for (pseudo)typeinfos.

Instead of the type_ctor_info being broken down into its components in
type_ctor_info.m, the breakdown process is now performed in rtti_out.m (for the
LLDS backend) and rtti_to_mlds.m (for the MLDS backend). Eventually, the IL and
Java backends will stop using rtti_to_mlds.m for this purpose, and will instead
write out the type_ctor_data structures as static data to be interpreted
directly.

We now predefine the C types representing type_info and pseudo_type_infos
for types of arity up to 20 for the LLDS C backend as well as for the
MLDS C backend. The LLDS backend can define them for higher arities
on demand; the MLDS backend (for now) still cannot.

runtime/mercury_type_info.h:
	To be able to represent all the kinds of types we now support

	- add a data structure for converting values of reserved_addr types
	  from their printable representation to their internal representation
	  (it was previously missing), and

	- add a type_ctor_rep to represent foreign types.

	Add missing MR_ prefixes on some field names.

	Add typedefs for all the types that the rtti_names can refer to.
	There were already such typedefs in runtime/mercury.h for the MLDS
	grades, we now have them for the LLDS grades too.

	Predefine the C types representing type_info and pseudo_type_infos
	for types of arity up to 20. There were already such typedefs in
	runtime/mercury.h for the MLDS grades, we now have them for the
	LLDS grades too.

runtime/mercury.h:
	Delete the typedefs that are now in mercury_type_info.h.

runtime/mercury.h:
	Delete the definitions of the C types representing type_info and
	pseudo_type_infos, since these are now in mercury_type_info.h.
	#include mercury_type_info.h.

compiler/rtti.m:
	Add new, purely Mercury data structures for representing
	type_ctor_infos and their components, designed both for efficient
	interpretation and as a source for the generation of static data
	structures in C.

	This entailed deleting most of the alternatives of the rtti_data type
	while preserving their rtti_name equivalents; the deleted alternatives
	represent tables are no longer created in type_ctor_info.m but which
	are created dynamically in rtti_out.m and rtti_to_mlds.m (which need
	a way for one table to refer to another).

	Centralize the correspondence between rtti_names and the C and Java
	types of the corresponding structures (the C and Java names differ in
	prefixes only). Among other things, this remove the double maintenance
	problem we have previously with the LLDS and MLDS backends maintaining
	their own maps of the correspondence.

	Add utility predicates on the new data structures for use by both
	rtti_out.m and rtti_to_mlds.m.

compiler/hlds_module.m:
	Always store the ids of unification and comparison procedures in
	type_ctor_gen_infos, to simplify their handling.

compiler/type_ctor_info.m:
	Generate the new data structures for representing type_ctor_infos.

	Conform to the changed data structures for type_ctor_gen_infos.

compiler/rtti_out.m:
compiler/rtti_to_mlds.m:
	Rewrite substantial parts of these modules to convert the new data
	structures for representing type_ctor_infos to sets of discrete
	structures dynamically.

	Most of the dynamically created structures are unique by construction,
	but this is not true for typeinfos and pseudo-typeinfos. Therefore
	add mechanisms to ensure that we don't generate redundant structures
	representing typeinfos and pseudo-typeinfos.

compiler/mlds_to_c.m:
compiler/mlds_to_java.m:
	Use the standard mechanisms for creating C and Java type names.

compiler/mlds_to_gcc.m:
	Conform to the changed data structures in rtti.m and
	mercury_type_info.h.

compiler/opt_debug.m:
	Conform to the changed data structures in rtti.m.

compiler/dead_proc_elim.m:
	Conform to the changed data structures for type_ctor_gen_infos.

compiler/pseudo_type_info.m:
	Add a predicate to construct a representation of a type that may or may
	not be ground.

compiler/mlds_to_gcc.m:
java/runtime/TypeCtorRep.java:
library/private_builtin.m:
library/rtti_implemenation.m:
runtime/mercury_mcpp.{cpp,h}:
	Add the type_ctor_rep for foreign types to the lists of type_ctor_reps.

library/construct.m:
library/deconstruct.m:
	Add missing MR_ prefixes on field names.

runtime/mercury_construct.c:
runtime/mercury_deconstruct.c:
runtime/mercury_deep_copy_body.h:
runtime/mercury_ml_expand_body.h:
runtime/mercury_tabling.c:
runtime/mercury_type_info.c:
runtime/mercury_unify_compare_body.h:
	Handle the type_ctor_rep for foreign types.

	Add missing MR_ prefixes on field names.

library/list.m:
	Add two utility predicates, is_empty and is_not_empty, for use with
	higher order code.

NEWS:
	Mention the new predicates in list.m. Delete a duplicate entry.

compiler/mlds_to_java.m

@@ -1668,8 +1668,9 @@ output_type(mlds__commit_type) -->
 % generated as such.
 %
 output_type(mlds__rtti_type(RttiName)) -->
-	io__write_string("static mercury.runtime."),
-	io__write_string(mlds_rtti_type_name(RttiName)).
+	{ rtti_name_java_type(RttiName, JavaTypeName, _IsArray) },
+	io__write_string("static "),
+	io__write_string(JavaTypeName).
 output_type(mlds__unknown_type) -->
 	{ unexpected(this_file, "output_type: unknown type") }.