/* CFG cleanup for trees.
- Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
+ Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
Free Software Foundation, Inc.
This file is part of GCC.
#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"
/* For conditions try harder and lookup single-argument
PHI nodes. Only do so from the same basic-block though
as other basic-blocks may be dead already. */
- if (TREE_CODE (lhs) == SSA_NAME)
+ if (TREE_CODE (lhs) == SSA_NAME
+ && !name_registered_for_update_p (lhs))
{
gimple def_stmt = SSA_NAME_DEF_STMT (lhs);
if (gimple_code (def_stmt) == GIMPLE_PHI
&& gimple_phi_num_args (def_stmt) == 1
- && gimple_bb (def_stmt) == gimple_bb (stmt))
+ && gimple_bb (def_stmt) == gimple_bb (stmt)
+ && (TREE_CODE (PHI_ARG_DEF (def_stmt, 0)) != SSA_NAME
+ || !name_registered_for_update_p (PHI_ARG_DEF (def_stmt,
+ 0))))
lhs = PHI_ARG_DEF (def_stmt, 0);
}
- if (TREE_CODE (rhs) == SSA_NAME)
+ if (TREE_CODE (rhs) == SSA_NAME
+ && !name_registered_for_update_p (rhs))
{
gimple def_stmt = SSA_NAME_DEF_STMT (rhs);
if (gimple_code (def_stmt) == GIMPLE_PHI
&& gimple_phi_num_args (def_stmt) == 1
- && gimple_bb (def_stmt) == gimple_bb (stmt))
+ && gimple_bb (def_stmt) == gimple_bb (stmt)
+ && (TREE_CODE (PHI_ARG_DEF (def_stmt, 0)) != SSA_NAME
+ || !name_registered_for_update_p (PHI_ARG_DEF (def_stmt,
+ 0))))
rhs = PHI_ARG_DEF (def_stmt, 0);
}
val = fold_binary_loc (loc, gimple_cond_code (stmt),
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
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;
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,
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
gimple label;
edge_iterator ei;
gimple_stmt_iterator gsi, gsi_to;
+ bool can_move_debug_stmts;
/* We check for infinite loops already in tree_forwarder_block_p.
However it may happen that the infinite loop is created
}
}
+ can_move_debug_stmts = single_pred_p (dest);
+
/* Redirect the edges. */
for (ei = ei_start (bb->preds); (e = ei_safe_edge (ei)); )
{
/* Move debug statements if the destination has just a single
predecessor. */
- if (single_pred_p (dest))
+ if (can_move_debug_stmts)
{
gsi_to = gsi_after_labels (dest);
for (gsi = gsi_after_labels (bb); !gsi_end_p (gsi); )
{
- if (!is_gimple_debug (gsi_stmt (gsi)))
+ gimple debug = gsi_stmt (gsi);
+ if (!is_gimple_debug (debug))
break;
gsi_remove (&gsi, false);
- gsi_insert_before (&gsi_to, label, GSI_SAME_STMT);
+ gsi_insert_before (&gsi_to, debug, GSI_SAME_STMT);
}
}
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;