2011-10-30 Steven G. Kargl <kargl@gcc.gnu.org>

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

diff --git a/gcc/tree-cfgcleanup.c b/gcc/tree-cfgcleanup.c
index fc2141f..0c8c085 100644 (file)
--- a/gcc/tree-cfgcleanup.c
+++ b/gcc/tree-cfgcleanup.c
@@ -26,7 +26,7 @@ along with GCC; see the file COPYING3.  If not see
 #include "tm_p.h"
 #include "basic-block.h"
 #include "output.h"
-#include "toplev.h"
+#include "diagnostic-core.h"
 #include "flags.h"
 #include "function.h"
 #include "ggc.h"
@@ -35,7 +35,6 @@ along with GCC; see the file COPYING3.  If not see
 #include "timevar.h"
 #include "tree-dump.h"
 #include "tree-pass.h"
-#include "toplev.h"
 #include "except.h"
 #include "cfgloop.h"
 #include "cfglayout.h"
@@ -278,9 +277,7 @@ tree_forwarder_block_p (basic_block bb, bool phi_wanted)
       || (single_succ_edge (bb)->flags & EDGE_ABNORMAL))
     return false;
 
-#if ENABLE_CHECKING
-  gcc_assert (bb != ENTRY_BLOCK_PTR);
-#endif
+  gcc_checking_assert (bb != ENTRY_BLOCK_PTR);
 
   locus = single_succ_edge (bb)->goto_locus;
 
@@ -337,21 +334,6 @@ tree_forwarder_block_p (basic_block bb, bool phi_wanted)
   return true;
 }
 
-/* Return true if BB has at least one abnormal incoming edge.  */
-
-static inline bool
-has_abnormal_incoming_edge_p (basic_block bb)
-{
-  edge e;
-  edge_iterator ei;
-
-  FOR_EACH_EDGE (e, ei, bb->preds)
-    if (e->flags & EDGE_ABNORMAL)
-      return true;
-
-  return false;
-}
-
 /* If all the PHI nodes in DEST have alternatives for E1 and E2 and
    those alternatives are equal in each of the PHI nodes, then return
    true, else return false.  */
@@ -417,8 +399,8 @@ remove_forwarder_block (basic_block bb)
 
      So if there is an abnormal edge to BB, proceed only if there is
      no abnormal edge to DEST and there are no phi nodes in DEST.  */
-  if (has_abnormal_incoming_edge_p (bb)
-      && (has_abnormal_incoming_edge_p (dest)
+  if (bb_has_abnormal_pred (bb)
+      && (bb_has_abnormal_pred (dest)
          || !gimple_seq_empty_p (phi_nodes (dest))))
     return false;
 
@@ -438,7 +420,7 @@ remove_forwarder_block (basic_block bb)
        }
     }
 
-  can_move_debug_stmts = single_pred_p (dest);
+  can_move_debug_stmts = MAY_HAVE_DEBUG_STMTS && single_pred_p (dest);
 
   /* Redirect the edges.  */
   for (ei = ei_start (bb->preds); (e = ei_safe_edge (ei)); )
@@ -494,8 +476,7 @@ remove_forwarder_block (basic_block bb)
        gsi_next (&gsi);
     }
 
-  /* Move debug statements if the destination has just a single
-     predecessor.  */
+  /* Move debug statements if the destination has a single predecessor.  */
   if (can_move_debug_stmts)
     {
       gsi_to = gsi_after_labels (dest);
@@ -559,22 +540,41 @@ fixup_noreturn_call (gimple stmt)
     {
       tree op = gimple_call_lhs (stmt);
       gimple_call_set_lhs (stmt, NULL_TREE);
-      /* We need to remove SSA name to avoid checking.
+
+      /* We need to remove SSA name to avoid checking errors.
         All uses are dominated by the noreturn and thus will
-        be removed afterwards.  */
+        be removed afterwards.
+        We proactively remove affected non-PHI statements to avoid
+        fixup_cfg from trying to update them and crashing.  */
       if (TREE_CODE (op) == SSA_NAME)
        {
          use_operand_p use_p;
           imm_use_iterator iter;
          gimple use_stmt;
+         bitmap_iterator bi;
+         unsigned int bb_index;
+
+         bitmap blocks = BITMAP_ALLOC (NULL);
 
           FOR_EACH_IMM_USE_STMT (use_stmt, iter, op)
-           FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
-             SET_USE (use_p, error_mark_node);
+           {
+             if (gimple_code (use_stmt) != GIMPLE_PHI)
+               bitmap_set_bit (blocks, gimple_bb (use_stmt)->index);
+             else
+               FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
+                 SET_USE (use_p, error_mark_node);
+           }
+         EXECUTE_IF_SET_IN_BITMAP (blocks, 0, bb_index, bi)
+           delete_basic_block (BASIC_BLOCK (bb_index));
+         BITMAP_FREE (blocks);
+         release_ssa_name (op);
        }
       update_stmt (stmt);
       changed = true;
     }
+  /* Similarly remove VDEF if there is any.  */
+  else if (gimple_vdef (stmt))
+    update_stmt (stmt);
   return changed;
 }
 
@@ -599,7 +599,7 @@ split_bbs_on_noreturn_calls (void)
           BB is present in the cfg.  */
        if (bb == NULL
            || bb->index < NUM_FIXED_BLOCKS
-           || bb->index >= n_basic_blocks
+           || bb->index >= last_basic_block
            || BASIC_BLOCK (bb->index) != bb
            || !gimple_call_noreturn_p (stmt))
          continue;
@@ -774,7 +774,10 @@ cleanup_tree_cfg_noloop (void)
 static void
 repair_loop_structures (void)
 {
-  bitmap changed_bbs = BITMAP_ALLOC (NULL);
+  bitmap changed_bbs;
+
+  timevar_push (TV_REPAIR_LOOPS);
+  changed_bbs = BITMAP_ALLOC (NULL);
   fix_loop_structure (changed_bbs);
 
   /* This usually does nothing.  But sometimes parts of cfg that originally
@@ -791,6 +794,7 @@ repair_loop_structures (void)
   scev_reset ();
 
   loops_state_clear (LOOPS_NEED_FIXUP);
+  timevar_pop (TV_REPAIR_LOOPS);
 }
 
 /* Cleanup cfg and repair loop structures.  */
@@ -881,7 +885,7 @@ remove_forwarder_block_with_phi (basic_block bb)
                 redirection, replace it with the PHI argument that used
                 to be on E.  */
              head = redirect_edge_var_map_vector (e);
-             for (i = 0; VEC_iterate (edge_var_map, head, i, vm); ++i)
+             FOR_EACH_VEC_ELT (edge_var_map, head, i, vm)
                {
                  tree old_arg = redirect_edge_var_map_result (vm);
                  tree new_arg = redirect_edge_var_map_def (vm);
@@ -970,7 +974,7 @@ merge_phi_nodes (void)
       if (gimple_seq_empty_p (phi_nodes (dest))
          /* We don't want to deal with a basic block with
             abnormal edges.  */
-         || has_abnormal_incoming_edge_p (bb))
+         || bb_has_abnormal_pred (bb))
        continue;
 
       if (!dominated_by_p (CDI_DOMINATORS, dest, bb))
@@ -1050,7 +1054,7 @@ struct gimple_opt_pass pass_merge_phi =
   0,                           /* properties_provided */
   0,                           /* properties_destroyed */
   0,                           /* todo_flags_start */
-  TODO_dump_func | TODO_ggc_collect    /* todo_flags_finish */
+  TODO_ggc_collect             /* todo_flags_finish */
   | TODO_verify_ssa
  }
 };