PR c++/37877

[pf3gnuchains/gcc-fork.git] / gcc / cfgcleanup.c

diff --git a/gcc/cfgcleanup.c b/gcc/cfgcleanup.c
index a778e28..190bde6 100644 (file)
--- a/gcc/cfgcleanup.c
+++ b/gcc/cfgcleanup.c
@@ -429,7 +429,7 @@ try_forward_edges (int mode, basic_block b)
   for (ei = ei_start (b->succs); (e = ei_safe_edge (ei)); )
     {
       basic_block target, first;
-      int counter;
+      int counter, goto_locus;
       bool threaded = false;
       int nthreaded_edges = 0;
       bool may_thread = first_pass | df_get_bb_dirty (b);
@@ -447,6 +447,7 @@ try_forward_edges (int mode, basic_block b)
 
       target = first = e->dest;
       counter = NUM_FIXED_BLOCKS;
+      goto_locus = e->goto_locus;
 
       /* If we are partitioning hot/cold basic_blocks, we don't want to mess
         up jumps that cross between hot/cold sections.
@@ -476,6 +477,28 @@ try_forward_edges (int mode, basic_block b)
              new_target = single_succ (target);
              if (target == new_target)
                counter = n_basic_blocks;
+             else if (!optimize)
+               {
+                 /* When not optimizing, ensure that edges or forwarder
+                    blocks with different locus are not optimized out.  */
+                 int locus = single_succ_edge (target)->goto_locus;
+
+                 if (locus && goto_locus && !locator_eq (locus, goto_locus))
+                   counter = n_basic_blocks;
+                 else if (locus)
+                   goto_locus = locus;
+
+                 if (INSN_P (BB_END (target)))
+                   {
+                     locus = INSN_LOCATOR (BB_END (target));
+
+                     if (locus && goto_locus
+                         && !locator_eq (locus, goto_locus))
+                       counter = n_basic_blocks;
+                     else if (locus)
+                       goto_locus = locus;
+                   }
+               }
            }
 
          /* Allow to thread only over one edge at time to simplify updating
@@ -539,6 +562,8 @@ try_forward_edges (int mode, basic_block b)
          int edge_frequency;
          int n = 0;
 
+         e->goto_locus = goto_locus;
+
          /* Don't force if target is exit block.  */
          if (threaded && target != EXIT_BLOCK_PTR)
            {