re PR tree-optimization/24226 (ICE: Segmentation fault in operand_equal_p…

re PR tree-optimization/24226 (ICE: Segmentation fault in operand_equal_p (complete loop unrolling))

	PR tree-optimization/24226
	* tree-cfg.c (remove_bb): Clean up unreachable loops.
	* tree-flow.h (free_numbers_of_iterations_estimates_loop): Declare.
	* tree-ssa-loop-niter.c (free_numbers_of_iterations_estimates_loop):
	Export.

From-SVN: r105151

gcc/ChangeLog

+2005-10-09  Zdenek Dvorak  <dvorakz@suse.cz>
+
+	PR tree-optimization/24226
+	* tree-cfg.c (remove_bb): Clean up unreachable loops.
+	* tree-flow.h (free_numbers_of_iterations_estimates_loop): Declare.
+	* tree-ssa-loop-niter.c (free_numbers_of_iterations_estimates_loop):
+	Export.
+
 2005-10-09  Eric Botcazou  <ebotcazou@libertysurf.fr>
 
 	* config/sparc/gmon-sol2.c (internal_mcount): Mark as used.

gcc/tree-cfg.c

@@ -2020,6 +2020,12 @@ remove_bb (basic_block bb)
 	{
 	  loop->latch = NULL;
 	  loop->header = NULL;
+
+	  /* Also clean up the information associated with the loop.  Updating
+	     it would waste time. More importantly, it may refer to ssa
+	     names that were defined in other removed basic block -- these
+	     ssa names are now removed and invalid.  */
+	  free_numbers_of_iterations_estimates_loop (loop);
 	}
     }
 

gcc/tree-flow.h

@@ -735,6 +735,7 @@ bool scev_probably_wraps_p (tree, tree, tree, tree, struct loop *, bool *,
 			    bool *);
 tree convert_step (struct loop *, tree, tree, tree, tree);
 void free_numbers_of_iterations_estimates (struct loops *);
+void free_numbers_of_iterations_estimates_loop (struct loop *);
 void rewrite_into_loop_closed_ssa (bitmap, unsigned);
 void verify_loop_closed_ssa (void);
 void loop_commit_inserts (void);

gcc/tree-ssa-loop-niter.c

@@ -2007,11 +2007,13 @@ convert_step (struct loop *loop, tree new_type, tree base, tree step,
 
 /* Frees the information on upper bounds on numbers of iterations of LOOP.  */
 
-static void
+void
 free_numbers_of_iterations_estimates_loop (struct loop *loop)
 {
   struct nb_iter_bound *bound, *next;
 
+  loop->nb_iterations = NULL;
+  loop->estimated_nb_iterations = NULL;
   for (bound = loop->bounds; bound; bound = next)
     {
       next = bound->next;