re PR middle-end/21840 (ICE while building Linux kernel (seg fault), missing cast)

2005-07-12  Andrew Pinski  <pinskia@physics.uc.edu>

        PR tree-opt/21840
        * tree-ssa-pre.c (eliminate): Convert the sprime to the correct type
        if *rhs_p is not a SSA_NAME.

2005-07-12  Andrew Pinski  <pinskia@physics.uc.edu>

        PR tree-opt/21840
        * gcc.c-torture/compile/pr21840.c: New test.

From-SVN: r101960

gcc/ChangeLog

+2005-07-12  Andrew Pinski  <pinskia@physics.uc.edu>
+
+	PR tree-opt/21840
+	* tree-ssa-pre.c (eliminate): Convert the sprime to the correct type
+	if *rhs_p is not a SSA_NAME.
+
 2005-07-12  Daniel Berlin  <dberlin@dberlin.org>
 	
 	Fix PR tree-optimization/22422 

gcc/testsuite/ChangeLog

+2005-07-12  Andrew Pinski  <pinskia@physics.uc.edu>
+
+	PR tree-opt/21840
+	* gcc.c-torture/compile/pr21840.c: New test.
+
 2005-07-12  Jan Hubicka  <jh@suse.cz>
 
 	* gcc.c-torture/compile/pr22379.c: New test.

gcc/testsuite/gcc.c-torture/compile/pr21840.c

+void fn_show_state(void);
+typedef void (*fn_handler_fn)(void);
+static fn_handler_fn fn_handler[1];
+
+void k_spec(unsigned char value)
+{
+  void *func = fn_handler[value];
+  if (func == fn_show_state )
+    return;
+  fn_handler[value]();
+}

gcc/tree-ssa-pre.c

@@ -2334,8 +2334,17 @@ eliminate (void)
 		      fprintf (dump_file, " in ");
 		      print_generic_stmt (dump_file, stmt, 0);
 		    }
+		  
 		  if (TREE_CODE (sprime) == SSA_NAME) 
 		    NECESSARY (SSA_NAME_DEF_STMT (sprime)) = 1;
+		  /* We need to make sure the new and old types actually match,
+		     which may require adding a simple cast, which fold_convert
+		     will do for us.  */
+		  if (TREE_CODE (*rhs_p) != SSA_NAME
+		      && !tree_ssa_useless_type_conversion_1 (TREE_TYPE (*rhs_p),
+							      TREE_TYPE (sprime)))
+		    sprime = fold_convert (TREE_TYPE (*rhs_p), sprime);
+		  
 		  pre_stats.eliminations++;
 		  propagate_tree_value (rhs_p, sprime);
 		  update_stmt (stmt);