2010-11-13 Paolo Bonzini <bonzini@gnu.org>

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

diff --git a/gcc/cfghooks.c b/gcc/cfghooks.c
index 00d7151..c6e4bc0 100644 (file)
--- a/gcc/cfghooks.c
+++ b/gcc/cfghooks.c
@@ -28,7 +28,7 @@ along with GCC; see the file COPYING3.  If not see
 #include "basic-block.h"
 #include "tree-flow.h"
 #include "timevar.h"
-#include "toplev.h"
+#include "diagnostic-core.h"
 #include "cfgloop.h"
 
 /* A pointer to one of the hooks containers.  */
@@ -56,6 +56,18 @@ gimple_register_cfg_hooks (void)
   cfg_hooks = &gimple_cfg_hooks;
 }
 
+struct cfg_hooks
+get_cfg_hooks (void)
+{
+  return *cfg_hooks;
+}
+
+void
+set_cfg_hooks (struct cfg_hooks new_cfg_hooks)
+{
+  *cfg_hooks = new_cfg_hooks;
+}
+
 /* Returns current ir type.  */
 
 enum ir_type
@@ -76,7 +88,7 @@ current_ir_type (void)
    Currently it does following: checks edge and basic block list correctness
    and calls into IL dependent checking then.  */
 
-void
+DEBUG_FUNCTION void
 verify_flow_info (void)
 {
   size_t *edge_checksum;
@@ -413,6 +425,7 @@ edge
 split_block (basic_block bb, void *i)
 {
   basic_block new_bb;
+  edge res;
 
   if (!cfg_hooks->split_block)
     internal_error ("%s does not support split_block", cfg_hooks->name);
@@ -424,6 +437,7 @@ split_block (basic_block bb, void *i)
   new_bb->count = bb->count;
   new_bb->frequency = bb->frequency;
   new_bb->loop_depth = bb->loop_depth;
+  new_bb->discriminator = bb->discriminator;
 
   if (dom_info_available_p (CDI_DOMINATORS))
     {
@@ -438,7 +452,15 @@ split_block (basic_block bb, void *i)
        bb->loop_father->latch = new_bb;
     }
 
-  return make_single_succ_edge (bb, new_bb, EDGE_FALLTHRU);
+  res = make_single_succ_edge (bb, new_bb, EDGE_FALLTHRU);
+
+  if (bb->flags & BB_IRREDUCIBLE_LOOP)
+    {
+      new_bb->flags |= BB_IRREDUCIBLE_LOOP;
+      res->flags |= EDGE_IRREDUCIBLE_LOOP;
+    }
+
+  return res;
 }
 
 /* Splits block BB just after labels.  The newly created edge is returned.  */
@@ -719,6 +741,8 @@ make_forwarder_block (basic_block bb, bool (*redirect_edge_p) (edge),
   /* Redirect back edges we want to keep.  */
   for (ei = ei_start (dummy->preds); (e = ei_safe_edge (ei)); )
     {
+      basic_block e_src;
+
       if (redirect_edge_p (e))
        {
          ei_next (&ei);
@@ -735,10 +759,21 @@ make_forwarder_block (basic_block bb, bool (*redirect_edge_p) (edge),
       if (fallthru->count < 0)
        fallthru->count = 0;
 
+      e_src = e->src;
       jump = redirect_edge_and_branch_force (e, bb);
-      if (jump != NULL
-         && new_bb_cbk != NULL)
-       new_bb_cbk (jump);
+      if (jump != NULL)
+        {
+          /* If we redirected the loop latch edge, the JUMP block now acts like
+             the new latch of the loop.  */
+          if (current_loops != NULL
+              && dummy->loop_father != NULL
+              && dummy->loop_father->header == dummy
+              && dummy->loop_father->latch == e_src)
+            dummy->loop_father->latch = jump;
+
+          if (new_bb_cbk != NULL)
+            new_bb_cbk (jump);
+        }
     }
 
   if (dom_info_available_p (CDI_DOMINATORS))
@@ -795,7 +830,7 @@ tidy_fallthru_edge (edge e)
 /* Fix up edges that now fall through, or rather should now fall through
    but previously required a jump around now deleted blocks.  Simplify
    the search by only examining blocks numerically adjacent, since this
-   is how find_basic_blocks created them.  */
+   is how they were created.  */
 
 void
 tidy_fallthru_edges (void)
@@ -818,9 +853,9 @@ tidy_fallthru_edges (void)
         a single successor.
 
         If we had a conditional branch to the next instruction when
-        find_basic_blocks was called, then there will only be one
-        out edge for the block which ended with the conditional
-        branch (since we do not create duplicate edges).
+        CFG was built, then there will only be one out edge for the
+        block which ended with the conditional branch (since we do
+        not create duplicate edges).
 
         Furthermore, the edge will be marked as a fallthru because we
         merge the flags for the duplicate edges.  So we do not want to
@@ -871,9 +906,7 @@ duplicate_block (basic_block bb, edge e, basic_block after)
   if (bb->count < new_count)
     new_count = bb->count;
 
-#ifdef ENABLE_CHECKING
-  gcc_assert (can_duplicate_block_p (bb));
-#endif
+  gcc_checking_assert (can_duplicate_block_p (bb));
 
   new_bb = cfg_hooks->duplicate_block (bb);
   if (after)