re PR tree-optimization/27381 (ice on valid code with -O)

2006-05-02  Andrew MacLeod  <amacleod@redhat.com>

        PR tree-optimization/27381
	* tree-phinodes.c (remove_phi_arg_num): When moving a phi argument, 
	maintain the same immediate_use links.
	* tree-ssa-operands.c (dump_immediate_uses_for): Show iteration marker 
	node rather than segfaulting.

From-SVN: r113499

gcc/ChangeLog

+2006-05-02  Andrew MacLeod  <amacleod@redhat.com>
+
+	PR tree-optimization/27381
+	* tree-phinodes.c (remove_phi_arg_num): When moving a phi argument, 
+	maintain the same immediate_use links.
+	* tree-ssa-operands.c (dump_immediate_uses_for): Show iteration marker 
+	node rather than segfaulting.
+
 2006-05-03  Jakub Jelinek  <jakub@redhat.com>
 
 	PR fortran/27395

gcc/tree-phinodes.c

@@ -406,14 +406,20 @@ remove_phi_arg_num (tree phi, int i)
 
   gcc_assert (i < num_elem);
 
-  /* Delink the last item, which is being removed.  */
-  delink_imm_use (&(PHI_ARG_IMM_USE_NODE (phi, num_elem - 1)));
 
-  /* If we are not at the last element, switch the last element
-     with the element we want to delete.  */
+  /* Delink the item which is being removed.  */
+  delink_imm_use (&(PHI_ARG_IMM_USE_NODE (phi, i)));
+
+  /* If it is not the last element, move the last element
+     to the element we want to delete, resetting all the links. */
   if (i != num_elem - 1)
     {
-      SET_PHI_ARG_DEF (phi, i, PHI_ARG_DEF (phi, num_elem - 1));
+      use_operand_p old_p, new_p;
+      old_p = &PHI_ARG_IMM_USE_NODE (phi, num_elem - 1);
+      new_p = &PHI_ARG_IMM_USE_NODE (phi, i);
+      /* Set use on new node, and link into last elements's place.  */
+      *(new_p->use) = *(old_p->use);
+      relink_imm_use (new_p, old_p);
     }
 
   /* Shrink the vector and return.  Note that we do not have to clear

gcc/tree-ssa-operands.c

@@ -2513,10 +2513,13 @@ dump_immediate_uses_for (FILE *file, tree var)
 
   FOR_EACH_IMM_USE_FAST (use_p, iter, var)
     {
-      if (!is_gimple_reg (USE_FROM_PTR (use_p)))
-	print_generic_stmt (file, USE_STMT (use_p), TDF_VOPS);
+      if (use_p->stmt == NULL && use_p->use == NULL)
+        fprintf (file, "***end of stmt iterator marker***\n");
       else
-	print_generic_stmt (file, USE_STMT (use_p), TDF_SLIM);
+	if (!is_gimple_reg (USE_FROM_PTR (use_p)))
+	  print_generic_stmt (file, USE_STMT (use_p), TDF_VOPS);
+	else
+	  print_generic_stmt (file, USE_STMT (use_p), TDF_SLIM);
     }
   fprintf(file, "\n");
 }