Remove never looping loop in label_rtx_for_bb

This refactors the IL "walk" in a way to avoid the loop which will
never iterate.

2021-11-25  Richard Biener  <rguenther@suse.de>

	* cfgexpand.c (label_rtx_for_bb): Remove dead loop construct.

diff --git a/gcc/cfgexpand.c b/gcc/cfgexpand.c
index eb6466f4be6f72f589abb1055f69d0d323af5c80..fb84d469f1e771b70e075330c901ab5a7ebb2cf1 100644 (file)
--- a/gcc/cfgexpand.c
+++ b/gcc/cfgexpand.c
@@ -2461,9 +2461,6 @@ static hash_map<basic_block, rtx_code_label *> *lab_rtx_for_bb;
 static rtx_code_label *
 label_rtx_for_bb (basic_block bb ATTRIBUTE_UNUSED)
 {
-  gimple_stmt_iterator gsi;
-  tree lab;
-
   if (bb->flags & BB_RTL)
     return block_label (bb);
 
@@ -2472,21 +2469,12 @@ label_rtx_for_bb (basic_block bb ATTRIBUTE_UNUSED)
     return *elt;
 
   /* Find the tree label if it is present.  */
-
-  for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
-    {
-      glabel *lab_stmt;
-
-      lab_stmt = dyn_cast <glabel *> (gsi_stmt (gsi));
-      if (!lab_stmt)
-       break;
-
-      lab = gimple_label_label (lab_stmt);
-      if (DECL_NONLOCAL (lab))
-       break;
-
-      return jump_target_rtx (lab);
-    }
+  gimple_stmt_iterator gsi = gsi_start_bb (bb);
+  glabel *lab_stmt;
+  if (!gsi_end_p (gsi)
+      && (lab_stmt = dyn_cast <glabel *> (gsi_stmt (gsi)))
+      && !DECL_NONLOCAL (gimple_label_label (lab_stmt)))
+    return jump_target_rtx (gimple_label_label (lab_stmt));
 
   rtx_code_label *l = gen_label_rtx ();
   lab_rtx_for_bb->put (bb, l);