re PR rtl-optimization/47028 (gcc.dg/tree-ssa/tailrecursion-[57].c FAIL with…

re PR rtl-optimization/47028 (gcc.dg/tree-ssa/tailrecursion-[57].c FAIL with -foptimize-sibling-calls -fno-forward-propagate -fno-tree-copy-prop -fno-tree-dominator-opts)

	PR rtl-optimization/47028
	* cfgexpand.c (gimple_expand_cfg): Insert entry edge
	insertions after parm_birth_insn instead of at the beginning
	of first bb.

	* gcc.dg/pr47028.c: New test.

From-SVN: r168401

gcc/ChangeLog

+2011-01-02  Jakub Jelinek  <jakub@redhat.com>
+
+	PR rtl-optimization/47028
+	* cfgexpand.c (gimple_expand_cfg): Insert entry edge
+	insertions after parm_birth_insn instead of at the beginning
+	of first bb.
+
 2011-01-02  Mingjie Xing  <mingjie.xing@gmail.com>
 
 	* doc/generic.texi: Remove duplicated "@subsubsection Statements".

gcc/cfgexpand.c

@@ -4085,7 +4085,19 @@ gimple_expand_cfg (void)
       for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
 	{
 	  if (e->insns.r)
-	    commit_one_edge_insertion (e);
+	    {
+	      /* Avoid putting insns before parm_birth_insn.  */
+	      if (e->src == ENTRY_BLOCK_PTR
+		  && single_succ_p (ENTRY_BLOCK_PTR)
+		  && parm_birth_insn)
+		{
+		  rtx insns = e->insns.r;
+		  e->insns.r = NULL_RTX;
+		  emit_insn_after_noloc (insns, parm_birth_insn, e->dest);
+		}
+	      else
+		commit_one_edge_insertion (e);
+	    }
 	  else
 	    ei_next (&ei);
 	}

gcc/testsuite/ChangeLog

+2011-01-02  Jakub Jelinek  <jakub@redhat.com>
+
+	PR rtl-optimization/47028
+	* gcc.dg/pr47028.c: New test.
+
 2011-01-02  Nicola Pero  <nicola.pero@meta-innovation.com>
 
 	* objc.dg/protocol-forward-1.m: Removed TODO.

gcc/testsuite/gcc.dg/pr47028.c

+/* PR rtl-optimization/47028 */
+/* { dg-do run } */
+/* { dg-options "-O -foptimize-sibling-calls -fno-forward-propagate -fno-tree-copy-prop -fno-tree-dominator-opts" } */
+
+int
+fib (int n)
+{
+  if (n <= 1)
+    return 1;
+  return fib (n - 2) + fib (n - 1);
+}
+
+int
+main (void)
+{
+  if (fib (5) != 8)
+    __builtin_abort ();
+  return 0;
+}