re PR tree-optimization/44393 (ICE: verify_ssa failed: no immediate_use list…

re PR tree-optimization/44393 (ICE: verify_ssa failed: no immediate_use list with -Os -ftree-loop-distribution)

2010-06-26  Richard Guenther  <rguenther@suse.de>

	PR tree-optimization/44393
	* tree-loop-distribution.c (generate_loops_for_partition): Fix
	stmt removal and VOP renaming.
	(generate_memset_zero): Remove redundant stmt updating.
	* tree-flow.h (mark_virtual_ops_in_bb): Remove.
	* tree-cfg.c (mark_virtual_ops_in_bb): Likewise.

	* gcc.dg/pr44393.c: New testcase.

From-SVN: r161434

gcc/ChangeLog

+2010-06-26  Richard Guenther  <rguenther@suse.de>
+
+	PR tree-optimization/44393
+	* tree-loop-distribution.c (generate_loops_for_partition): Fix
+	stmt removal and VOP renaming.
+	(generate_memset_zero): Remove redundant stmt updating.
+	* tree-flow.h (mark_virtual_ops_in_bb): Remove.
+	* tree-cfg.c (mark_virtual_ops_in_bb): Likewise.
+
 2010-06-26  Jan Hubicka  <jh@suse.cz>
 
 	* ipa-split.c (consider_split): PHI in entry block is OK as long as all

gcc/testsuite/ChangeLog

+2010-06-26  Richard Guenther  <rguenther@suse.de>
+
+	PR tree-optimization/44393
+	* gcc.dg/pr44393.c: New testcase.
+
 2010-06-26  Jan Hubicka  <jh@suse.cz>
 
 	* gcc.dg/tree-ssa/ipa-split-2.c: New testcase.

gcc/testsuite/gcc.dg/pr44393.c

+/* { dg-do compile } */
+/* { dg-options "-Os -ftree-loop-distribution" } */
+
+int i;
+void foo ()
+{
+  int **pp = 0, *p = 0;
+  while (--i)
+    {
+      *p++ = 0;
+      *pp++ = p;
+    }
+  i = *p;
+}
+

gcc/tree-cfg.c

@@ -5792,21 +5792,6 @@ move_stmt_r (gimple_stmt_iterator *gsi_p, bool *handled_ops_p,
   return NULL_TREE;
 }
 
-/* Marks virtual operands of all statements in basic blocks BBS for
-   renaming.  */
-
-void
-mark_virtual_ops_in_bb (basic_block bb)
-{
-  gimple_stmt_iterator gsi;
-
-  for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
-    mark_virtual_ops_for_renaming (gsi_stmt (gsi));
-
-  for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
-    mark_virtual_ops_for_renaming (gsi_stmt (gsi));
-}
-
 /* Move basic block BB from function CFUN to function DEST_FN.  The
    block is moved out of the original linked list and placed after
    block AFTER in the new list.  Also, the block is removed from the

gcc/tree-flow.h

@@ -486,7 +486,6 @@ extern void end_recording_case_labels (void);
 extern basic_block move_sese_region_to_fn (struct function *, basic_block,
 				           basic_block, tree);
 void remove_edge_and_dominated_blocks (edge);
-void mark_virtual_ops_in_bb (basic_block);
 bool tree_node_can_be_shared (tree);
 
 /* In tree-cfgcleanup.c  */

gcc/tree-loop-distribution.c

@@ -195,18 +195,28 @@ generate_loops_for_partition (struct loop *loop, bitmap partition, bool copy_p)
 
       for (bsi = gsi_start_phis (bb); !gsi_end_p (bsi);)
 	if (!bitmap_bit_p (partition, x++))
-	  remove_phi_node (&bsi, true);
+	  {
+	    gimple phi = gsi_stmt (bsi);
+	    if (!is_gimple_reg (gimple_phi_result (phi)))
+	      mark_virtual_phi_result_for_renaming (phi);
+	    remove_phi_node (&bsi, true);
+	  }
 	else
 	  gsi_next (&bsi);
 
       for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi);)
-	if (gimple_code (gsi_stmt (bsi)) != GIMPLE_LABEL
-	    && !bitmap_bit_p (partition, x++))
-	  gsi_remove (&bsi, false);
-	else
-	  gsi_next (&bsi);
-
-	mark_virtual_ops_in_bb (bb);
+	{
+	  gimple stmt = gsi_stmt (bsi);
+	  if (gimple_code (gsi_stmt (bsi)) != GIMPLE_LABEL
+	      && !bitmap_bit_p (partition, x++))
+	    {
+	      unlink_stmt_vdef (stmt);
+	      gsi_remove (&bsi, true);
+	      release_defs (stmt);
+	    }
+	  else
+	    gsi_next (&bsi);
+	}
     }
 
   free (bbs);
@@ -240,7 +250,6 @@ generate_memset_zero (gimple stmt, tree op0, tree nb_iter,
   gimple_seq stmt_list = NULL, stmts;
   gimple fn_call;
   tree mem, fn;
-  gimple_stmt_iterator i;
   struct data_reference *dr = XCNEW (struct data_reference);
   location_t loc = gimple_location (stmt);
 
@@ -291,13 +300,6 @@ generate_memset_zero (gimple stmt, tree op0, tree nb_iter,
   fn = build_fold_addr_expr (implicit_built_in_decls [BUILT_IN_MEMSET]);
   fn_call = gimple_build_call (fn, 3, mem, integer_zero_node, nb_bytes);
   gimple_seq_add_stmt (&stmt_list, fn_call);
-
-  for (i = gsi_start (stmt_list); !gsi_end_p (i); gsi_next (&i))
-    {
-      gimple s = gsi_stmt (i);
-      update_stmt_if_modified (s);
-    }
-
   gsi_insert_seq_after (&bsi, stmt_list, GSI_CONTINUE_LINKING);
   res = true;