[m-rev.] diff: fix intermodule opt bug

[Julien Fischer]

I don't have a separate test case for this one as the bug is fairly sensitive
to a number of inlining parameters and extracting one from the standard
library (which was where it showed up) would be quite time consuming.  I have
an upcoming change to the io module that won't compile without this diff, so
that will have to suffice.

Estimated hours taken: 3
Branches: main, release

Fix a bug with intermodule optimization and termination analysis.  The problem
was that not all of the termination_info pragmas for all of the opt_exported
procedures were being written to the .opt file.  In some cases where the
procedure was defined by a foreign clause, this lead to the termination
foreign code attributes conflicting with the analyser's default assumptions
about procedures without termination_info pragmas.

This diff fixes the bug in one direction: making sure that we always adjust
the import status of items written to .opt files.  This is sufficient to get
the termination analyser to write out the missing termination_info pragmas.
(Previously we used to only do this if intermodule unused argument analysis
was enabled for some reason.)

I'm working on a separate fix in the other direction, i.e. making the
termination analyser a bit more robust with respect to missing information -
I'll post that as a separate diff.  (In any case this change is useful in it's
own right - it should improve accuracy).

compiler/intermod.m:
 	Always adjust the import status of items written to .opt files.

Julien.

Index: compiler/intermod.m
===================================================================
RCS file: /home/mercury/mercury1/repository/mercury/compiler/intermod.m,v
retrieving revision 1.208
diff -u -r1.208 intermod.m
--- compiler/intermod.m	7 Sep 2006 05:50:55 -0000	1.208
+++ compiler/intermod.m	28 Sep 2006 08:20:08 -0000
@@ -164,7 +164,6 @@
          globals.io_lookup_bool_option(deforestation, Deforestation, !IO),
          globals.io_lookup_int_option(higher_order_size_limit,
              HigherOrderSizeLimit, !IO),
-        globals.io_lookup_bool_option(intermod_unused_args, UnusedArgs, !IO),
          some [!IntermodInfo] (
              init_intermod_info(!.ModuleInfo, !:IntermodInfo),
              gather_preds(PredIds, yes, Threshold, HigherOrderSizeLimit,
@@ -175,12 +174,7 @@
              intermod_info_get_module_info(!.IntermodInfo, !:ModuleInfo),
              io.set_output_stream(OutputStream, _, !IO),
              io.close_output(FileStream, !IO),
-            (
-                UnusedArgs = yes,
-                do_adjust_pred_import_status(!.IntermodInfo, !ModuleInfo)
-            ;
-                UnusedArgs = no
-            )
+            do_adjust_pred_import_status(!.IntermodInfo, !ModuleInfo)
          )
      ),
      %

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