2010-04-20 Richard Guenther <rguenther@suse.de>

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

diff --git a/gcc/tree-cfgcleanup.c b/gcc/tree-cfgcleanup.c
index 723bfc1..b8f5a54 100644 (file)
--- a/gcc/tree-cfgcleanup.c
+++ b/gcc/tree-cfgcleanup.c
@@ -23,9 +23,7 @@ along with GCC; see the file COPYING3.  If not see
 #include "coretypes.h"
 #include "tm.h"
 #include "tree.h"
-#include "rtl.h"
 #include "tm_p.h"
-#include "hard-reg-set.h"
 #include "basic-block.h"
 #include "output.h"
 #include "toplev.h"
@@ -267,6 +265,7 @@ static bool
 tree_forwarder_block_p (basic_block bb, bool phi_wanted)
 {
   gimple_stmt_iterator gsi;
+  location_t locus;
 
   /* BB must have a single outgoing edge.  */
   if (single_succ_p (bb) != 1
@@ -285,6 +284,8 @@ tree_forwarder_block_p (basic_block bb, bool phi_wanted)
   gcc_assert (bb != ENTRY_BLOCK_PTR);
 #endif
 
+  locus = single_succ_edge (bb)->goto_locus;
+
   /* There should not be an edge coming from entry, or an EH edge.  */
   {
     edge_iterator ei;
@@ -293,6 +294,10 @@ tree_forwarder_block_p (basic_block bb, bool phi_wanted)
     FOR_EACH_EDGE (e, ei, bb->preds)
       if (e->src == ENTRY_BLOCK_PTR || (e->flags & EDGE_EH))
        return false;
+      /* If goto_locus of any of the edges differs, prevent removing
+        the forwarder block for -O0.  */
+      else if (optimize == 0 && e->goto_locus != locus)
+       return false;
   }
 
   /* Now walk through the statements backward.  We can ignore labels,
@@ -306,6 +311,8 @@ tree_forwarder_block_p (basic_block bb, bool phi_wanted)
        case GIMPLE_LABEL:
          if (DECL_NONLOCAL (gimple_label_label (stmt)))
            return false;
+         if (optimize == 0 && gimple_location (stmt) != locus)
+           return false;
          break;
 
          /* ??? For now, hope there's a corresponding debug
@@ -608,11 +615,7 @@ cleanup_tree_cfg_bb (basic_block bb)
 
   retval = cleanup_control_flow_bb (bb);
 
-  /* Forwarder blocks can carry line number information which is
-     useful when debugging, so we only clean them up when
-     optimizing.  */
-  if (optimize > 0
-      && tree_forwarder_block_p (bb, false)
+  if (tree_forwarder_block_p (bb, false)
       && remove_forwarder_block (bb))
     return true;