From: Zdenek Dvorak <rakdver@atrey.karlin.mff.cuni.cz>
Date: Sun, 12 Sep 2004 20:20:58 +0000 (+0200)
Subject: tree-ssa-loop-manip.c (split_loop_exit_edge): Handle non-ssaname arguments of the... 
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=7fac672272cce6ed7e6e8ca9a54116d40f303dd7;p=gcc.git

tree-ssa-loop-manip.c (split_loop_exit_edge): Handle non-ssaname arguments of the phi nodes correctly.

	* tree-ssa-loop-manip.c (split_loop_exit_edge): Handle non-ssaname
	arguments of the phi nodes correctly.

From-SVN: r87405
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index cea290af667..59d386e5318 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2004-09-12  Zdenek Dvorak  <rakdver@atrey.karlin.mff.cuni.cz>
+
+	* tree-ssa-loop-manip.c (split_loop_exit_edge): Handle non-ssaname
+	arguments of the phi nodes correctly.
+
 2004-09-12  Jan Hubicka  <jh@suse.cz>
 
 	* ggc-common.c (cmp_statistics): Fix sorting.
diff --git a/gcc/tree-ssa-loop-manip.c b/gcc/tree-ssa-loop-manip.c
index cde3ce8fb4d..e6ff8a80559 100644
--- a/gcc/tree-ssa-loop-manip.c
+++ b/gcc/tree-ssa-loop-manip.c
@@ -395,17 +395,26 @@ split_loop_exit_edge (edge exit)
 {
   basic_block dest = exit->dest;
   basic_block bb = loop_split_edge_with (exit, NULL);
-  tree phi, new_phi, new_name;
+  tree phi, new_phi, new_name, name;
   use_operand_p op_p;
 
   for (phi = phi_nodes (dest); phi; phi = TREE_CHAIN (phi))
     {
       op_p = PHI_ARG_DEF_PTR_FROM_EDGE (phi, bb->succ);
 
-      new_name = duplicate_ssa_name (USE_FROM_PTR (op_p), NULL);
+      name = USE_FROM_PTR (op_p);
+
+      /* If the argument of the phi node is a constant, we do not need
+	 to keep it inside loop.  */
+      if (TREE_CODE (name) != SSA_NAME)
+	continue;
+
+      /* Otherwise create an auxiliary phi node that will copy the value
+	 of the ssa name out of the loop.  */
+      new_name = duplicate_ssa_name (name, NULL);
       new_phi = create_phi_node (new_name, bb);
       SSA_NAME_DEF_STMT (new_name) = new_phi;
-      add_phi_arg (&new_phi, USE_FROM_PTR (op_p), exit);
+      add_phi_arg (&new_phi, name, exit);
       SET_USE (op_p, new_name);
     }
 }