/*

 * Copyright (c) 1997, 2014, 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.

 *

 */

#include "precompiled.hpp"

#include "opto/callnode.hpp"

#include "opto/cfgnode.hpp"

#include "opto/matcher.hpp"

#include "opto/mathexactnode.hpp"

#include "opto/multnode.hpp"

#include "opto/opcodes.hpp"

#include "opto/phaseX.hpp"

#include "opto/regmask.hpp"

#include "opto/type.hpp"

//=============================================================================

//------------------------------MultiNode--------------------------------------

const RegMask &MultiNode::out_RegMask() const {

  return RegMask::Empty;

}

Node *MultiNode::match( const ProjNode *proj, const Matcher *m ) { return proj->clone(); }

//------------------------------proj_out---------------------------------------

// Get a named projection

ProjNode* MultiNode::proj_out(uint which_proj) const {

  assert(Opcode() != Op_If || which_proj == (uint)true || which_proj == (uint)false, "must be 1 or 0");

  assert(Opcode() != Op_If || outcnt() == 2, "bad if #1");

  for( DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++ ) {

    Node *p = fast_out(i);

    if (p->is_Proj()) {

      ProjNode *proj = p->as_Proj();

      if (proj->_con == which_proj) {

        assert(Opcode() != Op_If || proj->Opcode() == (which_proj?Op_IfTrue:Op_IfFalse), "bad if #2");

        return proj;

      }

    } else {

      assert(p == this && this->is_Start(), "else must be proj");

      continue;

    }

  }

  return NULL;

}

//=============================================================================

//------------------------------ProjNode---------------------------------------

uint ProjNode::hash() const {

  // only one input

  return (uintptr_t)in(TypeFunc::Control) + (_con << 1) + (_is_io_use ? 1 : 0);

}

uint ProjNode::cmp( const Node &n ) const { return _con == ((ProjNode&)n)._con && ((ProjNode&)n)._is_io_use == _is_io_use; }

uint ProjNode::size_of() const { return sizeof(ProjNode); }

// Test if we propagate interesting control along this projection

bool ProjNode::is_CFG() const {

  Node *def = in(0);

  return (_con == TypeFunc::Control && def->is_CFG());

}

const Type* ProjNode::proj_type(const Type* t) const {

  if (t == Type::TOP) {

    return Type::TOP;

  }

  if (t == Type::BOTTOM) {

    return Type::BOTTOM;

  }

  t = t->is_tuple()->field_at(_con);

  Node* n = in(0);

  if ((_con == TypeFunc::Parms) &&

      n->is_CallStaticJava() && n->as_CallStaticJava()->is_boxing_method()) {

    // The result of autoboxing is always non-null on normal path.

    t = t->join_speculative(TypePtr::NOTNULL);

  }

  return t;

}

const Type *ProjNode::bottom_type() const {

  if (in(0) == NULL) return Type::TOP;

  return proj_type(in(0)->bottom_type());

}

const TypePtr *ProjNode::adr_type() const {

  if (bottom_type() == Type::MEMORY) {

    // in(0) might be a narrow MemBar; otherwise we will report TypePtr::BOTTOM

    Node* ctrl = in(0);

    if (ctrl == NULL)  return NULL; // node is dead

    const TypePtr* adr_type = ctrl->adr_type();

    #ifdef ASSERT

    if (!is_error_reported() && !Node::in_dump())

      assert(adr_type != NULL, "source must have adr_type");

    #endif

    return adr_type;

  }

  assert(bottom_type()->base() != Type::Memory, "no other memories?");

  return NULL;

}

bool ProjNode::pinned() const { return in(0)->pinned(); }

#ifndef PRODUCT

void ProjNode::dump_spec(outputStream *st) const { st->print("#%d",_con); if(_is_io_use) st->print(" (i_o_use)");}

#endif

//----------------------------check_con----------------------------------------

void ProjNode::check_con() const {

  Node* n = in(0);

  if (n == NULL)       return;  // should be assert, but NodeHash makes bogons

  if (n->is_Mach())    return;  // mach. projs. are not type-safe

  if (n->is_Start())   return;  // alas, starts can have mach. projs. also

  if (_con == SCMemProjNode::SCMEMPROJCON ) return;

  const Type* t = n->bottom_type();

  if (t == Type::TOP)  return;  // multi is dead

  assert(_con < t->is_tuple()->cnt(), "ProjNode::_con must be in range");

}

//------------------------------Value------------------------------------------

const Type *ProjNode::Value( PhaseTransform *phase ) const {

  if (in(0) == NULL) return Type::TOP;

  return proj_type(phase->type(in(0)));

}

//------------------------------out_RegMask------------------------------------

// Pass the buck uphill

const RegMask &ProjNode::out_RegMask() const {

  return RegMask::Empty;

}

//------------------------------ideal_reg--------------------------------------

uint ProjNode::ideal_reg() const {

  return bottom_type()->ideal_reg();

}

//-------------------------------is_uncommon_trap_proj----------------------------

// Return true if proj is the form of "proj->[region->..]call_uct"

bool ProjNode::is_uncommon_trap_proj(Deoptimization::DeoptReason reason) {

  int path_limit = 10;

  Node* out = this;

  for (int ct = 0; ct < path_limit; ct++) {

    out = out->unique_ctrl_out();

    if (out == NULL)

      return false;

    if (out->is_CallStaticJava()) {

      int req = out->as_CallStaticJava()->uncommon_trap_request();

      if (req != 0) {

        Deoptimization::DeoptReason trap_reason = Deoptimization::trap_request_reason(req);

        if (trap_reason == reason || reason == Deoptimization::Reason_none) {

           return true;

        }

      }

      return false; // don't do further after call

    }

    if (out->Opcode() != Op_Region)

      return false;

  }

  return false;

}

//-------------------------------is_uncommon_trap_if_pattern-------------------------

// Return true  for "if(test)-> proj -> ...

//                          |

//                          V

//                      other_proj->[region->..]call_uct"

//

// "must_reason_predicate" means the uct reason must be Reason_predicate

bool ProjNode::is_uncommon_trap_if_pattern(Deoptimization::DeoptReason reason) {

  Node *in0 = in(0);

  if (!in0->is_If()) return false;

  // Variation of a dead If node.

  if (in0->outcnt() < 2)  return false;

  IfNode* iff = in0->as_If();

  // we need "If(Conv2B(Opaque1(...)))" pattern for reason_predicate

  if (reason != Deoptimization::Reason_none) {

    if (iff->in(1)->Opcode() != Op_Conv2B ||

       iff->in(1)->in(1)->Opcode() != Op_Opaque1) {

      return false;

    }

  }

  ProjNode* other_proj = iff->proj_out(1-_con);

  if (other_proj == NULL) // Should never happen, but make Parfait happy.

      return false;

  if (other_proj->is_uncommon_trap_proj(reason)) {

    assert(reason == Deoptimization::Reason_none ||

           Compile::current()->is_predicate_opaq(iff->in(1)->in(1)), "should be on the list");

    return true;

  }

  return false;

}