Some fixes to the Java back-end, to make it work again after

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Some fixes to the Java back-end, to make it work again after
Zoltan's recent type class RTTI changes.

java/runtime/DuExistInfo.java:
	Add a new field "exist_constraints" to the DuExistInfo type
	and a corresponding argument to the constructor, to match
	Zoltan's recent changes.

java/runtime/TypeClassId.java:
java/runtime/TypeClassMethod.java:
java/runtime/TypeClassDeclStruct.java:
java/runtime/TypeClassConstraint.java:
	New files.  These correspond to the C types MR_TypeClassId,
	MR_TypeClassMethod, MR_TypeClassDeclStruct,
	and MR_TypeClassConstraint in the C runtime.

java/runtime/TypeCtorInfo_Struct.java:
	Add a comment.

compiler/rtti_to_mlds.m:
	Don't cast null pointers to mlds__generic_type; they should have
	the right type already.  Casting to mlds__generic_type here causes
	type errors for the Java back-end, because in Java there are no
	implicit conversions from Object (unlike C, which allows implicit
	conversions from `void *').

compiler/rtti.m:
	Change tc_rtti_name_java_type so that it maps the new typeclass-related
	RTTI types to the appropriate Java types.

library/private_builtin.m:
	Define MR_PREDICATE and MR_FUNCTION.

java/runtime/PredFunc.java:
	Fix a bug in my previous change:
		s/MR_PRED/MR_PREDICATE/
		s/MR_FUNC/MR_FUNCTION/

compiler/rtti.m

@@ -1703,11 +1703,27 @@ ctor_rtti_name_java_type(RttiName, JavaTypeName, IsArray) :-
 		JavaTypeName = string__append("mercury.runtime.", GenTypeName0)
 	).
 
-tc_rtti_name_java_type(_TCRttiName, JavaTypeName, IsArray) :-
-	JavaTypeName = "java.lang.Object",
-	IsArray = yes.
-	% tc_rtti_name_type(TCRttiName, _GenTypeName, IsArray),
-	% JavaTypeName = string__append("mercury.runtime.", GenTypeName).
+tc_rtti_name_java_type(TCRttiName, JavaTypeName, IsArray) :-
+	tc_rtti_name_type(TCRttiName, GenTypeName, IsArray),
+	(
+		% BaseTypeClassInfo in C is represented using a
+		% variable-length array as the last field,
+		% so we need to handle it specially in Java
+		GenTypeName = "BaseTypeclassInfo"
+	->
+		JavaTypeName = "java.lang.Object" /* & IsArray = yes */
+	;
+		% Java doesn't have typedefs (or "const"),
+		% so we need to use "String" rather than "ConstString"
+		GenTypeName = "ConstString"
+	->
+		JavaTypeName = "java.lang.String"
+	;
+		% The rest are all defined in Mercury's Java runtime
+		% (java/runtime/*.java).
+		JavaTypeName = string__append("mercury.runtime.",
+			GenTypeName)
+	).
 
 	% ctor_rtti_name_type(RttiName, Type, IsArray):
 :- pred ctor_rtti_name_type(ctor_rtti_name::in, string::out, bool::out) is det.

compiler/rtti_to_mlds.m

@@ -1507,8 +1507,7 @@ gen_init_maybe(Type, _Conv, no) = gen_init_null_pointer(Type).
 	
 :- func gen_init_null_pointer(mlds__type) = mlds__initializer.
 
-gen_init_null_pointer(Type) =
-	init_obj(mlds__unop(cast(mlds__generic_type), const(null(Type)))).
+gen_init_null_pointer(Type) = init_obj(const(null(Type))).
 
 :- func gen_init_string(string) = mlds__initializer.
 

java/runtime/DuExistInfo.java

@@ -1,5 +1,5 @@
 //
-// Copyright (C) 2001-2003 The University of Melbourne.
+// Copyright (C) 2001-2004 The University of Melbourne.
 // This file may only be copied under the terms of the GNU Library General
 // Public License - see the file COPYING.LIB in the Mercury distribution.
 //
@@ -12,13 +12,17 @@ public class DuExistInfo {
 	public int exist_typeinfos_in_tci;
 	public int exist_tcis;
 	public /* final */ mercury.runtime.DuExistLocn[] exist_typeinfo_locns;
+	public /* final */ mercury.runtime.TypeClassConstraint[]
+		exist_constraints;
 
 	public DuExistInfo(int typeinfos_plain, int typeinfos_in_tci, int tcis,
-		mercury.runtime.DuExistLocn[] typeinfo_locns)
+		mercury.runtime.DuExistLocn[] typeinfo_locns,
+		mercury.runtime.TypeClassConstraint constraints[])
 	{
 		exist_typeinfos_plain = typeinfos_plain;
 		exist_typeinfos_in_tci = typeinfos_in_tci;
 		exist_tcis = tcis;
 		exist_typeinfo_locns = typeinfo_locns;
+		exist_constraints = constraints;
 	}
 }

java/runtime/PredFunc.java

@@ -8,8 +8,8 @@ package mercury.runtime;
 
 public class PredFunc {
 	
-	public static final int MR_PRED = 0;
-	public static final int MR_FUNC = 1;
+	public static final int MR_PREDICATE = 0;
+	public static final int MR_FUNCTION = 1;
 
 	public int value;
 

java/runtime/TypeClassConstraint.java

@@ -0,0 +1,64 @@
+//
+// Copyright (C) 2004 The University of Melbourne.
+// This file may only be copied under the terms of the GNU Library General
+// Public License - see the file COPYING.LIB in the Mercury distribution.
+//
+
+package mercury.runtime;
+
+// This corresponds to the C type MR_TypeClassConstraint
+// in runtime/mercury_type_info.h.
+
+public class TypeClassConstraint {
+	public TypeClassDeclStruct	tc_constr_type_class;
+	public PseudoTypeInfo		tc_constr_arg_ptis[];
+
+	public TypeClassConstraint(TypeClassDeclStruct type_class)
+	{
+		tc_constr_type_class = type_class;
+		tc_constr_arg_ptis = new PseudoTypeInfo[] {};
+	}
+
+	public TypeClassConstraint(TypeClassDeclStruct type_class,
+		PseudoTypeInfo pti1)
+	{
+		tc_constr_type_class = type_class;
+		tc_constr_arg_ptis = new PseudoTypeInfo[] { pti1 };
+	}
+
+	public TypeClassConstraint(TypeClassDeclStruct type_class,
+		PseudoTypeInfo pti1, PseudoTypeInfo pti2)
+	{
+		tc_constr_type_class = type_class;
+		tc_constr_arg_ptis = new PseudoTypeInfo[] { pti1, pti2 };
+	}
+
+	public TypeClassConstraint(TypeClassDeclStruct type_class,
+		PseudoTypeInfo pti1, PseudoTypeInfo pti2,
+		PseudoTypeInfo pti3)
+	{
+		tc_constr_type_class = type_class;
+		tc_constr_arg_ptis = new PseudoTypeInfo[] { pti1, pti2, pti3 };
+	}
+
+	public TypeClassConstraint(TypeClassDeclStruct type_class,
+		PseudoTypeInfo pti1, PseudoTypeInfo pti2,
+		PseudoTypeInfo pti3, PseudoTypeInfo pti4)
+	{
+		tc_constr_type_class = type_class;
+		tc_constr_arg_ptis = new PseudoTypeInfo[]
+			{ pti1, pti2, pti3, pti4 };
+	}
+
+	public TypeClassConstraint(TypeClassDeclStruct type_class,
+		PseudoTypeInfo pti1, PseudoTypeInfo pti2,
+		PseudoTypeInfo pti3, PseudoTypeInfo pti4,
+		PseudoTypeInfo pti5)
+	{
+		tc_constr_type_class = type_class;
+		tc_constr_arg_ptis = new PseudoTypeInfo[] {
+			pti1, pti2, pti3, pti4, pti5 };
+	}
+
+	// XXX type classes with arity > 5 not supported
+}

java/runtime/TypeClassDeclStruct.java

@@ -0,0 +1,27 @@
+//
+// Copyright (C) 2004 The University of Melbourne.
+// This file may only be copied under the terms of the GNU Library General
+// Public License - see the file COPYING.LIB in the Mercury distribution.
+//
+
+package mercury.runtime;
+
+// This corresponds to the C typedef "MR_TypeClassDeclStruct"
+// in runtime/mercury_types.h, i.e. the C struct
+// "struct MR_TypeClassDecl_Struct" in runtime/mercury_typeclass_info.h.
+
+public class TypeClassDeclStruct {
+	public TypeClassId		tc_decl_id;
+	public int			tc_decl_version_number;
+	public int			tc_decl_num_supers; // redundant
+	public TypeClassConstraint	tc_decl_supers;
+
+	public TypeClassDeclStruct(TypeClassId id, int version_number,
+		int num_supers, TypeClassConstraint supers)
+	{
+		tc_decl_id = id;
+		tc_decl_version_number = version_number;
+		tc_decl_num_supers = num_supers;
+		tc_decl_supers = supers;
+	}
+}

java/runtime/TypeClassId.java

@@ -0,0 +1,33 @@
+//
+// Copyright (C) 2004 The University of Melbourne.
+// This file may only be copied under the terms of the GNU Library General
+// Public License - see the file COPYING.LIB in the Mercury distribution.
+//
+
+package mercury.runtime;
+
+// This corresponds to the C type MR_TypeClassId
+// in runtime/mercury_typeclass_info.h.
+
+public class TypeClassId {
+	public String			tc_id_module_name;
+	public String			tc_id_name;
+	public int			tc_id_arity;
+	public int			tc_id_num_type_vars; // XXX redundant
+	public int			tc_id_num_methods;   // XXX redundant
+	public String[]			tc_id_var_names;
+	public TypeClassMethod[]	tc_id_methods;
+
+	public TypeClassId(String module_name, String name, int arity,
+		int num_type_vars, int num_methods,
+		String[] var_names, TypeClassMethod[] methods)
+	{
+		tc_id_module_name = module_name;
+		tc_id_name = name;
+		tc_id_arity = arity;
+		tc_id_num_type_vars = num_type_vars;
+		tc_id_num_methods = num_methods;
+		tc_id_var_names = var_names;
+		tc_id_methods = methods;
+	}
+}

java/runtime/TypeClassMethod.java

@@ -0,0 +1,24 @@
+//
+// Copyright (C) 2004 The University of Melbourne.
+// This file may only be copied under the terms of the GNU Library General
+// Public License - see the file COPYING.LIB in the Mercury distribution.
+//
+
+package mercury.runtime;
+
+// This corresponds to the C type MR_TypeClassMethod
+// in runtime/mercury_typeclass_info.h.
+
+public class TypeClassMethod {
+	public /* final */ java.lang.String		tc_method_name;
+	public /* final */ int				tc_method_arity;
+	public /* final */ int /* PredFunc */		tc_method_pred_func;
+
+	public TypeClassMethod(java.lang.String name, int arity,
+		int pred_func)
+	{
+		tc_method_name = name;
+		tc_method_arity = arity;
+		tc_method_pred_func = pred_func;
+	}
+}

java/runtime/TypeCtorInfo_Struct.java

@@ -1,11 +1,14 @@
 //
-// Copyright (C) 2001-2003 The University of Melbourne.
+// Copyright (C) 2001-2004 The University of Melbourne.
 // This file may only be copied under the terms of the GNU Library General
 // Public License - see the file COPYING.LIB in the Mercury distribution.
 //
 
 package mercury.runtime;
 
+// This corresponds to the C type "struct MR_TypeCtorInfo_Struct"
+// in runtime/mercury_type_info.h.
+
 public class TypeCtorInfo_Struct extends PseudoTypeInfo {
     
 	public int                              arity;

library/private_builtin.m

@@ -1288,6 +1288,9 @@ no_clauses(PredName) :-
     public static final int MR_SECTAG_REMOTE	= 2;
     public static final int MR_SECTAG_VARIABLE	= 3;
 
+    public static final int MR_PREDICATE	= 0;
+    public static final int MR_FUNCTION		= 1;
+
     // The dummy_var is used to represent io__states and other Mercury
     // parameters that are not really passed around.  Occasionally a dummy
     // variable will be used by the code generator as an lval, so we use