/*

 * Copyright (c) 1997, 2015, 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 "gc/shared/collectedHeap.hpp"

#include "opto/machnode.hpp"

#include "opto/regalloc.hpp"

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

// Return the value requested

// result register lookup, corresponding to int_format

int MachOper::reg(PhaseRegAlloc *ra_, const Node *node) const {

  return (int)ra_->get_encode(node);

}

// input register lookup, corresponding to ext_format

int MachOper::reg(PhaseRegAlloc *ra_, const Node *node, int idx) const {

  return (int)(ra_->get_encode(node->in(idx)));

}

intptr_t  MachOper::constant() const { return 0x00; }

relocInfo::relocType MachOper::constant_reloc() const { return relocInfo::none; }

jdouble MachOper::constantD() const { ShouldNotReachHere(); return 0.0; }

jfloat  MachOper::constantF() const { ShouldNotReachHere(); return 0.0; }

jlong   MachOper::constantL() const { ShouldNotReachHere(); return CONST64(0) ; }

TypeOopPtr *MachOper::oop() const { return NULL; }

int MachOper::ccode() const { return 0x00; }

// A zero, default, indicates this value is not needed.

// May need to lookup the base register, as done in int_ and ext_format

int MachOper::base (PhaseRegAlloc *ra_, const Node *node, int idx)  const { return 0x00; }

int MachOper::index(PhaseRegAlloc *ra_, const Node *node, int idx)  const { return 0x00; }

int MachOper::scale()  const { return 0x00; }

int MachOper::disp (PhaseRegAlloc *ra_, const Node *node, int idx)  const { return 0x00; }

int MachOper::constant_disp()  const { return 0; }

int MachOper::base_position()  const { return -1; }  // no base input

int MachOper::index_position() const { return -1; }  // no index input

// Check for PC-Relative displacement

relocInfo::relocType MachOper::disp_reloc() const { return relocInfo::none; }

// Return the label

Label*   MachOper::label()  const { ShouldNotReachHere(); return 0; }

intptr_t MachOper::method() const { ShouldNotReachHere(); return 0; }

//------------------------------negate-----------------------------------------

// Negate conditional branches.  Error for non-branch operands

void MachOper::negate() {

  ShouldNotCallThis();

}

//-----------------------------type--------------------------------------------

const Type *MachOper::type() const {

  return Type::BOTTOM;

}

//------------------------------in_RegMask-------------------------------------

const RegMask *MachOper::in_RegMask(int index) const {

  ShouldNotReachHere();

  return NULL;

}

//------------------------------dump_spec--------------------------------------

// Print any per-operand special info

#ifndef PRODUCT

void MachOper::dump_spec(outputStream *st) const { }

#endif

//------------------------------hash-------------------------------------------

// Print any per-operand special info

uint MachOper::hash() const {

  ShouldNotCallThis();

  return 5;

}

//------------------------------cmp--------------------------------------------

// Print any per-operand special info

uint MachOper::cmp( const MachOper &oper ) const {

  ShouldNotCallThis();

  return opcode() == oper.opcode();

}

//------------------------------hash-------------------------------------------

// Print any per-operand special info

uint labelOper::hash() const {

  return _block_num;

}

//------------------------------cmp--------------------------------------------

// Print any per-operand special info

uint labelOper::cmp( const MachOper &oper ) const {

  return (opcode() == oper.opcode()) && (_label == oper.label());

}

//------------------------------hash-------------------------------------------

// Print any per-operand special info

uint methodOper::hash() const {

  return (uint)_method;

}

//------------------------------cmp--------------------------------------------

// Print any per-operand special info

uint methodOper::cmp( const MachOper &oper ) const {

  return (opcode() == oper.opcode()) && (_method == oper.method());

}

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

//------------------------------MachNode---------------------------------------

//------------------------------emit-------------------------------------------

void MachNode::emit(CodeBuffer &cbuf, PhaseRegAlloc *ra_) const {

  #ifdef ASSERT

  tty->print("missing MachNode emit function: ");

  dump();

  #endif

  ShouldNotCallThis();

}

//---------------------------postalloc_expand----------------------------------

// Expand node after register allocation.

void MachNode::postalloc_expand(GrowableArray <Node *> *nodes, PhaseRegAlloc *ra_) {}

//------------------------------size-------------------------------------------

// Size of instruction in bytes

uint MachNode::size(PhaseRegAlloc *ra_) const {

  // If a virtual was not defined for this specific instruction,

  // Call the helper which finds the size by emitting the bits.

  return MachNode::emit_size(ra_);

}

//------------------------------size-------------------------------------------

// Helper function that computes size by emitting code

uint MachNode::emit_size(PhaseRegAlloc *ra_) const {

  // Emit into a trash buffer and count bytes emitted.

  assert(ra_ == ra_->C->regalloc(), "sanity");

  return ra_->C->scratch_emit_size(this);

}

//------------------------------hash-------------------------------------------

uint MachNode::hash() const {

  uint no = num_opnds();

  uint sum = rule();

  for( uint i=0; i<no; i++ )

    sum += _opnds[i]->hash();

  return sum+Node::hash();

}

//-----------------------------cmp---------------------------------------------

uint MachNode::cmp( const Node &node ) const {

  MachNode& n = *((Node&)node).as_Mach();

  uint no = num_opnds();

  if( no != n.num_opnds() ) return 0;

  if( rule() != n.rule() ) return 0;

  for( uint i=0; i<no; i++ )    // All operands must match

    if( !_opnds[i]->cmp( *n._opnds[i] ) )

      return 0;                 // mis-matched operands

  return 1;                     // match

}

// Return an equivalent instruction using memory for cisc_operand position

MachNode *MachNode::cisc_version(int offset) {

  ShouldNotCallThis();

  return NULL;

}

void MachNode::use_cisc_RegMask() {

  ShouldNotReachHere();

}

//-----------------------------in_RegMask--------------------------------------

const RegMask &MachNode::in_RegMask( uint idx ) const {

  uint numopnds = num_opnds();        // Virtual call for number of operands

  uint skipped   = oper_input_base(); // Sum of leaves skipped so far

  if( idx < skipped ) {

    assert( ideal_Opcode() == Op_AddP, "expected base ptr here" );

    assert( idx == 1, "expected base ptr here" );

    // debug info can be anywhere

    return *Compile::current()->matcher()->idealreg2spillmask[Op_RegP];

  }

  uint opcnt     = 1;                 // First operand

  uint num_edges = _opnds[1]->num_edges(); // leaves for first operand

  while( idx >= skipped+num_edges ) {

    skipped += num_edges;

    opcnt++;                          // Bump operand count

    assert( opcnt < numopnds, "Accessing non-existent operand" );

    num_edges = _opnds[opcnt]->num_edges(); // leaves for next operand

  }

  const RegMask *rm = cisc_RegMask();

  if( rm == NULL || (int)opcnt != cisc_operand() ) {

    rm = _opnds[opcnt]->in_RegMask(idx-skipped);

  }

  return *rm;

}

//-----------------------------memory_inputs--------------------------------

const MachOper*  MachNode::memory_inputs(Node* &base, Node* &index) const {

  const MachOper* oper = memory_operand();

  if (oper == (MachOper*)-1) {

    base = NodeSentinel;

    index = NodeSentinel;

  } else {

    base = NULL;

    index = NULL;

    if (oper != NULL) {

      // It has a unique memory operand.  Find its index.

      int oper_idx = num_opnds();

      while (--oper_idx >= 0) {

        if (_opnds[oper_idx] == oper)  break;

      }

      int oper_pos = operand_index(oper_idx);

      int base_pos = oper->base_position();

      if (base_pos >= 0) {

        base = _in[oper_pos+base_pos];

      }

      int index_pos = oper->index_position();

      if (index_pos >= 0) {

        index = _in[oper_pos+index_pos];

      }

    }

  }

  return oper;

}

//-----------------------------get_base_and_disp----------------------------

const Node* MachNode::get_base_and_disp(intptr_t &offset, const TypePtr* &adr_type) const {

  // Find the memory inputs using our helper function

  Node* base;

  Node* index;

  const MachOper* oper = memory_inputs(base, index);

  if (oper == NULL) {

    // Base has been set to NULL

    offset = 0;

  } else if (oper == (MachOper*)-1) {

    // Base has been set to NodeSentinel

    // There is not a unique memory use here.  We will fall to AliasIdxBot.

    offset = Type::OffsetBot;

  } else {

    // Base may be NULL, even if offset turns out to be != 0

    intptr_t disp = oper->constant_disp();

    int scale = oper->scale();

    // Now we have collected every part of the ADLC MEMORY_INTER.

    // See if it adds up to a base + offset.

    if (index != NULL) {

      const Type* t_index = index->bottom_type();

      if (t_index->isa_narrowoop() || t_index->isa_narrowklass()) { // EncodeN, LoadN, LoadConN, LoadNKlass,

                                                                    // EncodeNKlass, LoadConNklass.

        // Memory references through narrow oops have a

        // funny base so grab the type from the index:

        // [R12 + narrow_oop_reg<<3 + offset]

        assert(base == NULL, "Memory references through narrow oops have no base");

        offset = disp;

        adr_type = t_index->make_ptr()->add_offset(offset);

        return NULL;

      } else if (!index->is_Con()) {

        disp = Type::OffsetBot;

      } else if (disp != Type::OffsetBot) {

        const TypeX* ti = t_index->isa_intptr_t();

        if (ti == NULL) {

          disp = Type::OffsetBot;  // a random constant??

        } else {

          disp += ti->get_con() << scale;

        }

      }

    }

    offset = disp;

    // In i486.ad, indOffset32X uses base==RegI and disp==RegP,

    // this will prevent alias analysis without the following support:

    // Lookup the TypePtr used by indOffset32X, a compile-time constant oop,

    // Add the offset determined by the "base", or use Type::OffsetBot.

    if( adr_type == TYPE_PTR_SENTINAL ) {

      const TypePtr *t_disp = oper->disp_as_type();  // only !NULL for indOffset32X

      if (t_disp != NULL) {

        offset = Type::OffsetBot;

        const Type* t_base = base->bottom_type();

        if (t_base->isa_intptr_t()) {

          const TypeX *t_offset = t_base->is_intptr_t();

          if( t_offset->is_con() ) {

            offset = t_offset->get_con();

          }

        }

        adr_type = t_disp->add_offset(offset);

      } else if( base == NULL && offset != 0 && offset != Type::OffsetBot ) {

        // Use ideal type if it is oop ptr.

        const TypePtr *tp = oper->type()->isa_ptr();

        if( tp != NULL) {

          adr_type = tp;

        }

      }

    }

  }

  return base;

}

//---------------------------------adr_type---------------------------------

const class TypePtr *MachNode::adr_type() const {

  intptr_t offset = 0;

  const TypePtr *adr_type = TYPE_PTR_SENTINAL;  // attempt computing adr_type

  const Node *base = get_base_and_disp(offset, adr_type);

  if( adr_type != TYPE_PTR_SENTINAL ) {

    return adr_type;      // get_base_and_disp has the answer

  }

  // Direct addressing modes have no base node, simply an indirect

  // offset, which is always to raw memory.

  // %%%%% Someday we'd like to allow constant oop offsets which

  // would let Intel load from static globals in 1 instruction.

  // Currently Intel requires 2 instructions and a register temp.

  if (base == NULL) {

    // NULL base, zero offset means no memory at all (a null pointer!)

    if (offset == 0) {

      return NULL;

    }

    // NULL base, any offset means any pointer whatever

    if (offset == Type::OffsetBot) {

      return TypePtr::BOTTOM;

    }

    // %%% make offset be intptr_t

    assert(!Universe::heap()->is_in_reserved(cast_to_oop(offset)), "must be a raw ptr");

    return TypeRawPtr::BOTTOM;

  }

  // base of -1 with no particular offset means all of memory

  if (base == NodeSentinel)  return TypePtr::BOTTOM;

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

  if (t->isa_narrowoop() && Universe::narrow_oop_shift() == 0) {

    // 32-bit unscaled narrow oop can be the base of any address expression

    t = t->make_ptr();

  }

  if (t->isa_narrowklass() && Universe::narrow_klass_shift() == 0) {

    // 32-bit unscaled narrow oop can be the base of any address expression

    t = t->make_ptr();

  }

  if (t->isa_intptr_t() && offset != 0 && offset != Type::OffsetBot) {

    // We cannot assert that the offset does not look oop-ish here.

    // Depending on the heap layout the cardmark base could land

    // inside some oopish region.  It definitely does for Win2K.

    // The sum of cardmark-base plus shift-by-9-oop lands outside

    // the oop-ish area but we can't assert for that statically.

    return TypeRawPtr::BOTTOM;

  }

  const TypePtr *tp = t->isa_ptr();

  // be conservative if we do not recognize the type

  if (tp == NULL) {

    assert(false, "this path may produce not optimal code");

    return TypePtr::BOTTOM;

  }

  assert(tp->base() != Type::AnyPtr, "not a bare pointer");

  return tp->add_offset(offset);

}

//-----------------------------operand_index---------------------------------

int MachNode::operand_index( uint operand ) const {

  if( operand < 1 )  return -1;

  assert(operand < num_opnds(), "oob");

  if( _opnds[operand]->num_edges() == 0 )  return -1;

  uint skipped   = oper_input_base(); // Sum of leaves skipped so far

  for (uint opcnt = 1; opcnt < operand; opcnt++) {

    uint num_edges = _opnds[opcnt]->num_edges(); // leaves for operand

    skipped += num_edges;

  }

  return skipped;

}

int MachNode::operand_index(const MachOper *oper) const {

  uint skipped = oper_input_base(); // Sum of leaves skipped so far

  uint opcnt;

  for (opcnt = 1; opcnt < num_opnds(); opcnt++) {

    if (_opnds[opcnt] == oper) break;

    uint num_edges = _opnds[opcnt]->num_edges(); // leaves for operand

    skipped += num_edges;

  }

  if (_opnds[opcnt] != oper) return -1;

  return skipped;

}

//------------------------------peephole---------------------------------------

// Apply peephole rule(s) to this instruction

MachNode *MachNode::peephole(Block *block, int block_index, PhaseRegAlloc *ra_, int &deleted) {

  return NULL;

}

//------------------------------add_case_label---------------------------------

// Adds the label for the case

void MachNode::add_case_label( int index_num, Label* blockLabel) {

  ShouldNotCallThis();

}

//------------------------------method_set-------------------------------------

// Set the absolute address of a method

void MachNode::method_set( intptr_t addr ) {

  ShouldNotCallThis();

}

//------------------------------rematerialize----------------------------------

bool MachNode::rematerialize() const {

  // Temps are always rematerializable

  if (is_MachTemp()) return true;

  uint r = rule();              // Match rule

  if( r <  Matcher::_begin_rematerialize ||

      r >= Matcher::_end_rematerialize )

    return false;

  // For 2-address instructions, the input live range is also the output

  // live range.  Remateralizing does not make progress on the that live range.

  if( two_adr() )  return false;

  // Check for rematerializing float constants, or not

  if( !Matcher::rematerialize_float_constants ) {

    int op = ideal_Opcode();

    if( op == Op_ConF || op == Op_ConD )

      return false;

  }

  // Defining flags - can't spill these!  Must remateralize.

  if( ideal_reg() == Op_RegFlags )

    return true;

  // Stretching lots of inputs - don't do it.

  if( req() > 2 )

    return false;

  // Don't remateralize somebody with bound inputs - it stretches a

  // fixed register lifetime.

  uint idx = oper_input_base();

  if (req() > idx) {

    const RegMask &rm = in_RegMask(idx);

    if (rm.is_bound(ideal_reg()))

      return false;

  }

  return true;

}

#ifndef PRODUCT

//------------------------------dump_spec--------------------------------------

// Print any per-operand special info

void MachNode::dump_spec(outputStream *st) const {

  uint cnt = num_opnds();

  for( uint i=0; i<cnt; i++ ) {

    if (_opnds[i] != NULL) {

      _opnds[i]->dump_spec(st);

    } else {

      st->print(" _");

    }

  }

  const TypePtr *t = adr_type();

  if( t ) {

    Compile* C = Compile::current();

    if( C->alias_type(t)->is_volatile() )

      st->print(" Volatile!");

  }

}

//------------------------------dump_format------------------------------------

// access to virtual

void MachNode::dump_format(PhaseRegAlloc *ra, outputStream *st) const {

  format(ra, st); // access to virtual

}

#endif

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

#ifndef PRODUCT

void MachTypeNode::dump_spec(outputStream *st) const {

  if (_bottom_type != NULL) {

    _bottom_type->dump_on(st);

  } else {

    st->print(" NULL");

  }

}

#endif

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

int MachConstantNode::constant_offset() {

  // Bind the offset lazily.

  if (_constant.offset() == -1) {

    Compile::ConstantTable& constant_table = Compile::current()->constant_table();

    int offset = constant_table.find_offset(_constant);

    // If called from Compile::scratch_emit_size return the

    // pre-calculated offset.

    // NOTE: If the AD file does some table base offset optimizations

    // later the AD file needs to take care of this fact.