Do not record dependences from debug stmts in tail merging

The following avoids recording BB dependences for debug stmt uses.

	* tree-ssa-tail-merge.cc (same_succ_hash): Skip debug
	stmts.

diff --git a/gcc/tree-ssa-tail-merge.cc b/gcc/tree-ssa-tail-merge.cc
index f4e6ae6e8a2a187ab484db421cc3d267a5699de9..c8b4a79294d7aee6c3ca4328991c43360a8c8f7a 100644 (file)
--- a/gcc/tree-ssa-tail-merge.cc
+++ b/gcc/tree-ssa-tail-merge.cc
@@ -474,6 +474,9 @@ same_succ_hash (const same_succ *e)
        !gsi_end_p (gsi); gsi_next_nondebug (&gsi))
     {
       stmt = gsi_stmt (gsi);
+      if (is_gimple_debug (stmt))
+       continue;
+
       stmt_update_dep_bb (stmt);
       if (stmt_local_def (stmt))
        continue;