diff: fixes for --use-opt-files

[Simon Taylor]

Estimated hours taken: 0.5

Fix some problems with --use-opt-files.

compiler/mercury_compile.m:
	Do dead predicate elimination after make_hlds if
	--use-opt-files is set.
	If there is a `.opt' file for the current module
	and --use-opt-files is set, make sure the necessary
	predicates are exported.


Index: mercury_compile.m
===================================================================
RCS file: /home/staff/zs/imp/mercury/compiler/mercury_compile.m,v
retrieving revision 1.100
diff -u -t -u -r1.100 mercury_compile.m
--- mercury_compile.m	1998/06/18 06:06:37	1.100
+++ mercury_compile.m	1998/06/29 07:13:20
@@ -467,13 +467,14 @@
 
 mercury_compile__maybe_grab_optfiles(Imports0, Verbose, MaybeTransOptDeps, 
                 Imports, Error) -->
-        globals__io_lookup_bool_option(intermodule_optimization, UseOptInt),
+        globals__io_lookup_bool_option(intermodule_optimization, IntermodOpt),
+        globals__io_lookup_bool_option(use_opt_files, UseOptInt),
         globals__io_lookup_bool_option(make_optimization_interface,
                                                 MakeOptInt),
         globals__io_lookup_bool_option(transitive_optimization, TransOpt),
         globals__io_lookup_bool_option(make_transitive_opt_interface,
                 MakeTransOptInt),
-        ( { UseOptInt = yes, MakeOptInt = no } ->
+        ( { (UseOptInt = yes ; IntermodOpt = yes), MakeOptInt = no } ->
                 maybe_write_string(Verbose, "% Reading .opt files...\n"),
                 maybe_flush_output(Verbose),
                 intermod__grab_optfiles(Imports0, Imports1, Error1),
@@ -603,9 +604,10 @@
             mercury_compile__maybe_dump_hlds(HLDS2, "02", "typeclass"), !,
 
             globals__io_lookup_bool_option(intermodule_optimization, Intermod),
+            globals__io_lookup_bool_option(use_opt_files, UseOptFiles),
             globals__io_lookup_bool_option(make_optimization_interface,
                 MakeOptInt),
-            ( { Intermod = yes, MakeOptInt = no } ->
+            ( { (Intermod = yes; UseOptFiles = yes), MakeOptInt = no } ->
                 % Eliminate unnecessary clauses from `.opt' files,
                 % to speed up compilation. This must be done after
                 % typeclass instances have been checked, since that
@@ -694,6 +696,9 @@
 mercury_compile__maybe_write_optfile(MakeOptInt, HLDS0, HLDS) -->
         globals__io_lookup_bool_option(intermodule_optimization, Intermod),
         globals__io_lookup_bool_option(intermod_unused_args, IntermodArgs),
+        globals__io_lookup_accumulating_option(intermod_directories,
+                IntermodDirs),
+        globals__io_lookup_bool_option(use_opt_files, UseOptFiles),
         globals__io_lookup_bool_option(verbose, Verbose),
         globals__io_lookup_bool_option(statistics, Stats),
         globals__io_lookup_bool_option(termination, Termination),
@@ -735,11 +740,35 @@
                 module_name_to_file_name(ModuleName, ".opt", yes, OptName),
                 update_interface(OptName),
                 touch_interface_datestamp(ModuleName, ".optdate")
-        ; { Intermod = yes } ->
-                intermod__adjust_pred_import_status(HLDS0, HLDS)
         ;
-                { HLDS = HLDS0 }
+                % If there is a `.opt' file for this module the import
+                % status of items in the `.opt' file needs to be updated.
+                ( { Intermod = yes } ->
+                        { UpdateStatus = yes }
+                ; { UseOptFiles = yes } ->
+                        { module_info_name(HLDS0, ModuleName) },
+                        module_name_to_file_name(ModuleName,
+                                ".opt", no, OptName),
+                        search_for_file(IntermodDirs, OptName, Found),
+                        ( { Found = yes } ->
+                                { UpdateStatus = yes },
+                                io__seen
+                        ;
+                                { UpdateStatus = no }
+                        )
+                ;
+                        { UpdateStatus = no }
+                ),      
+                { is_bool(UpdateStatus) },
+                ( { UpdateStatus = yes } ->
+                        intermod__adjust_pred_import_status(HLDS0, HLDS)
+                ;
+                        { HLDS = HLDS0 }
+                )
         ).
+
+:- pred is_bool(bool::in) is det.
+is_bool(_).
 
 :- pred mercury_compile__output_trans_opt_file(module_info, 
         io__state, io__state).