1 files changed, 55 insertions, 0 deletions
diff --git a/gcc-4.6/gcc/cfgloop.c b/gcc-4.6/gcc/cfgloop.c
index 3f14551..28701d7 100644
--- a/gcc-4.6/gcc/cfgloop.c
+++ b/gcc-4.6/gcc/cfgloop.c
@@ -1640,3 +1640,58 @@ loop_exits_from_bb_p (struct loop *loop, basic_block bb)
 
   return false;
 }
+
+/* Return location corresponding to the loop control condition if possible. */
+
+location_t
+get_loop_location (struct loop *loop)
+{
+  rtx insn = NULL;
+  struct niter_desc *desc = NULL;
+  edge exit;
+
+  /* For a for or while loop, we would like to return the location
+   * of the for or while statement, if possible. To do this, look
+   * for the branch guarding the loop back-edge.
+   */
+
+  /* If this is a simple loop with an in_edge, then the loop control
+   * branch is typically at the end of its source.
+   */
+  desc = get_simple_loop_desc (loop);
+  if (desc->in_edge)
+    {
+      FOR_BB_INSNS_REVERSE (desc->in_edge->src, insn)
+        {
+          if (INSN_P (insn))
+            return RTL_LOCATION (insn);
+        }
+    }
+  /* If loop has a single exit, then the loop control branch
+   * must be at the end of its source.
+   */
+  if ((exit = single_exit(loop)))
+    {
+      FOR_BB_INSNS_REVERSE (exit->src, insn)
+        {
+          if (INSN_P (insn))
+            return RTL_LOCATION (insn);
+        }
+    }
+  /* Next check the latch, to see if it is non-empty. */
+  FOR_BB_INSNS_REVERSE (loop->latch, insn)
+    {
+      if (INSN_P (insn))
+        return RTL_LOCATION (insn);
+    }
+  /* Finally, if none of the above identifies the loop control branch,
+   * return the first location in the loop header.
+   */
+  FOR_BB_INSNS (loop->header, insn)
+    {
+      if (INSN_P (insn))
+        return RTL_LOCATION (insn);
+    }
+  /* If all else fails, simply return the current function location. */
+  return DECL_SOURCE_LOCATION (current_function_decl);
+}