/*

 * Copyright (c) 1997, 2010, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 *

 */

#ifndef SHARE_VM_OPTO_LIVE_HPP

#define SHARE_VM_OPTO_LIVE_HPP

#include "libadt/port.hpp"

#include "libadt/vectset.hpp"

#include "opto/block.hpp"

#include "opto/indexSet.hpp"

#include "opto/phase.hpp"

#include "opto/regmask.hpp"

class Block;

class PhaseCFG;

class VectorSet;

class IndexSet;

//------------------------------LRG_List---------------------------------------

// Map Node indices to Live RanGe indices.

// Array lookup in the optimized case.

class LRG_List : public ResourceObj {

  friend class VMStructs;

  uint _cnt, _max;

  uint* _lidxs;

  ReallocMark _nesting;         // assertion check for reallocations

public:

  LRG_List( uint max );

  uint lookup( uint nidx ) const {

    return _lidxs[nidx];

  }

  uint operator[] (uint nidx) const { return lookup(nidx); }

  void map( uint nidx, uint lidx ) {

    assert( nidx < _cnt, "oob" );

    _lidxs[nidx] = lidx;

  }

  void extend( uint nidx, uint lidx );

  uint Size() const { return _cnt; }

};

//------------------------------PhaseLive--------------------------------------

// Compute live-in/live-out

class PhaseLive : public Phase {

  // Array of Sets of values live at the start of a block.

  // Indexed by block pre-order number.

  IndexSet *_live;

  // Array of Sets of values defined locally in the block

  // Indexed by block pre-order number.

  IndexSet *_defs;

  // Array of delta-set pointers, indexed by block pre-order number

  IndexSet **_deltas;

  IndexSet *_free_IndexSet;     // Free list of same

  Block_List *_worklist;        // Worklist for iterative solution

  const PhaseCFG &_cfg;         // Basic blocks

  const LRG_List &_names;       // Mapping from Nodes to live ranges

  uint _maxlrg;                 // Largest live-range number

  Arena *_arena;

  IndexSet *getset( Block *p );

  IndexSet *getfreeset( );

  void freeset( const Block *p );

  void add_liveout( Block *p, uint r, VectorSet &first_pass );

  void add_liveout( Block *p, IndexSet *lo, VectorSet &first_pass );

public:

  PhaseLive(const PhaseCFG &cfg, const LRG_List &names, Arena *arena);

  ~PhaseLive() {}

  // Compute liveness info

  void compute(uint maxlrg);

  // Reset arena storage

  void reset() { _live = NULL; }

  // Return the live-out set for this block

  IndexSet *live( const Block * b ) { return &_live[b->_pre_order-1]; }

#ifndef PRODUCT

  void dump( const Block *b ) const;

  void stats(uint iters) const;

#endif

};

#endif // SHARE_VM_OPTO_LIVE_HPP