diff: modes.m: new option --mode-inference-iteration-limit

[Fergus Henderson]

Estimated hours taken: 1

compiler/options.m:
	Add a new option `--mode-inference-iteration-limit'.

compiler/modes.m:
	Use the new option rather than a hard-coded limit.

doc/user_guide.texi:
	Document the new option.

cvs diff compiler/modes.m compiler/options.m doc/user_guide.texi
Index: compiler/modes.m
===================================================================
RCS file: /home/staff/zs/imp/mercury/compiler/modes.m,v
retrieving revision 1.205
diff -u -r1.205 modes.m
--- modes.m	1997/09/15 21:12:24	1.205
+++ modes.m	1997/11/02 17:17:52
@@ -303,7 +303,8 @@
 
 check_pred_modes(ModuleInfo0, ModuleInfo, UnsafeToContinue) -->
 	{ module_info_predids(ModuleInfo0, PredIds) },
-	{ MaxIterations = 30 }, % XXX FIXME should be command-line option
+	globals__io_lookup_int_option(mode_inference_iteration_limit,
+		MaxIterations),
 	modecheck_to_fixpoint(PredIds, MaxIterations, ModuleInfo0,
 					ModuleInfo1, UnsafeToContinue),
 	write_mode_inference_messages(PredIds, ModuleInfo1),
@@ -349,8 +350,15 @@
 
 report_max_iterations_exceeded -->
 	io__set_exit_status(1),
-	io__write_string("Mode analysis iteration limit exceeded.\n").
-	% XXX FIXME add verbose_errors message
+	io__write_strings([
+	   "Mode analysis iteration limit exceeded.\n",
+	   "You may need to declare the modes explicitly, or use the\n",
+	   "`--mode-inference-iteration-limit' option to increase the limit.\n"
+	]),
+	globals__io_lookup_int_option(mode_inference_iteration_limit,
+		MaxIterations),
+	io__format("(The current limit is %d iterations.)\n",
+		[i(MaxIterations)]).
 
 :- pred modecheck_pred_modes_2(list(pred_id), module_info, module_info,
 			bool, bool, int, int, io__state, io__state).
Index: compiler/options.m
===================================================================
RCS file: /home/staff/zs/imp/mercury/compiler/options.m,v
retrieving revision 1.208
diff -u -r1.208 options.m
--- options.m	1997/10/14 09:07:42	1.208
+++ options.m	1997/11/02 14:33:21
@@ -100,6 +100,7 @@
 		;	infer_modes
 		;	infer_det
 		;	infer_all
+		;	mode_inference_iteration_limit
 	% Compilation Model options
 		;	grade
 		;	gcc_non_local_gotos
@@ -333,7 +334,8 @@
 	infer_types		-	bool(no),
 	infer_modes		-	bool(no),
 	infer_det		-	bool(yes),
-	infer_all		-	bool_special
+	infer_all		-	bool_special,
+	mode_inference_iteration_limit	-	int(30)
 ]).
 option_defaults_2(compilation_model_option, [
 		% Compilation model options (ones that affect binary
@@ -626,6 +628,8 @@
 long_option("infer-modes",		infer_modes).
 long_option("infer-determinism",	infer_det).
 long_option("infer-det",		infer_det).
+long_option("mode-inference-iteration-limit",
+					mode_inference_iteration_limit).
 
 % compilation model options
 long_option("grade",			grade).
@@ -1238,7 +1242,10 @@
 
 	io__write_string("\t--no-infer-det, --no-infer-determinism\n"),
 	io__write_string("\t\tIf there is no determinism declaration for a procedure,\n"),
-	io__write_string("\t\tdon't try to infer the determinism, just report an error.\n").
+	io__write_string("\t\tdon't try to infer the determinism, just report an error.\n"),
+	io__write_string("\t--mode-inference-iteration-limit <n>\n"),
+	io__write_string("\t\tPerform at most <n> passes of mode inference (default: 30).\n").
+
 
 :- pred options_help_compilation_model(io__state::di, io__state::uo) is det.
 
Index: doc/user_guide.texi
===================================================================
RCS file: /home/staff/zs/imp/mercury/doc/user_guide.texi,v
retrieving revision 1.101
diff -u -r1.101 user_guide.texi
--- user_guide.texi	1997/10/14 09:34:56	1.101
+++ user_guide.texi	1997/11/02 14:44:29
@@ -1485,6 +1485,9 @@
 If there is no determinism declaration for a procedure,
 don't try to infer the determinism, just report an error.
 
+ at sp 1
+ at item --mode-inference-iteration-limit @var{n}
+Perform at most @var{n} passes of mode inference (default: 30).
 @end table
 
 @node Compilation model options

-- 
Fergus Henderson <fjh at cs.mu.oz.au>   |  "I have always known that the pursuit
WWW: <http://www.cs.mu.oz.au/~fjh>   |  of excellence is a lethal habit"
PGP: finger fjh at 128.250.37.3         |     -- the last words of T. S. Garp.