jdk/src/hotspot/share/opto/multnode.cpp

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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#include "opto/callnode.hpp"
#include "opto/cfgnode.hpp"
#include "opto/inlinetypenode.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"
#include "utilities/vmError.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 or null if not found
ProjNode* MultiNode::proj_out_or_null(uint which_proj) const {
  assert((Opcode() != Op_If && Opcode() != Op_RangeCheck) || which_proj == (uint)true || which_proj == (uint)false, "must be 1 or 0");
  assert(number_of_projs(which_proj) <= 1, "only when there's a single projection");
  ProjNode* proj = find_first(which_proj);
  assert(proj == nullptr || (Opcode() != Op_If && Opcode() != Op_RangeCheck) || proj->Opcode() == (which_proj ? Op_IfTrue : Op_IfFalse),
         "incorrect projection node at If/RangeCheck: IfTrue on false path or IfFalse on true path");
  return proj;
}

ProjNode* MultiNode::proj_out_or_null(uint which_proj, bool is_io_use) const {
  assert(number_of_projs(which_proj, is_io_use) <= 1, "only when there's a single projection");
  return find_first(which_proj, is_io_use);
}

template<class Callback> ProjNode* MultiNode::apply_to_projs(Callback callback, uint which_proj, bool is_io_use) const {
  auto filter = [&](ProjNode* proj) {
    if (proj->_is_io_use == is_io_use && callback(proj) == BREAK_AND_RETURN_CURRENT_PROJ) {
      return BREAK_AND_RETURN_CURRENT_PROJ;
    }
    return CONTINUE;
  };
  return apply_to_projs(filter, which_proj);
}

uint MultiNode::number_of_projs(uint which_proj) const {
  uint cnt = 0;
  auto count_projs = [&](ProjNode* proj) {
    cnt++;
  };
  for_each_proj(count_projs, which_proj);
  return cnt;
}

uint MultiNode::number_of_projs(uint which_proj, bool is_io_use) const {
  uint cnt = 0;
  auto count_projs = [&](ProjNode* proj) {
    cnt++;
  };
  for_each_proj(count_projs, which_proj, is_io_use);
  return cnt;
}

ProjNode* MultiNode::find_first(uint which_proj) const {
  auto find_proj = [&](ProjNode* proj) {
    return BREAK_AND_RETURN_CURRENT_PROJ;
  };
  return apply_to_projs(find_proj, which_proj);
}

ProjNode* MultiNode::find_first(uint which_proj, bool is_io_use) const {
  auto find_proj = [](ProjNode* proj) {
    return BREAK_AND_RETURN_CURRENT_PROJ;
  };
  return apply_to_projs(find_proj, which_proj, is_io_use);
}

// Get a named projection
ProjNode* MultiNode::proj_out(uint which_proj) const {
  assert((Opcode() != Op_If && Opcode() != Op_RangeCheck) || outcnt() == 2, "bad if #1");
  ProjNode* p = proj_out_or_null(which_proj);
  assert(p != nullptr, "named projection %u not found", which_proj);
  return p;
}

//=============================================================================
//------------------------------ProjNode---------------------------------------
uint ProjNode::hash() const {
  // only one input
  return (uintptr_t)in(TypeFunc::Control) + (_con << 1) + (_is_io_use ? 1 : 0);
}
bool 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);
  CallStaticJavaNode* call = in(0)->isa_CallStaticJava();
  if (call != nullptr && call->is_boxing_method()) {
    // The result of autoboxing is always non-null on normal path.
    if (call->tf()->returns_inline_type_as_fields()) {
      // Last returned value is the null marker
      if (_con == call->tf()->range_cc()->cnt() - 1) {
        t = TypeInt::ONE;
      }
    } else if (_con == TypeFunc::Parms) {
      t = t->join_speculative(TypePtr::NOTNULL);
    }
  }
  return t;
}

const Type *ProjNode::bottom_type() const {
  if (in(0) == nullptr) 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->Opcode() == Op_Tuple) {
      // Jumping over Tuples: the i-th projection of a Tuple is the i-th input of the Tuple.
      ctrl = ctrl->in(_con);
    }
    // node is dead or we are in the process of removing a dead subgraph
    if (ctrl == nullptr || ctrl->is_top()) {
      return nullptr;
    }
    const TypePtr* adr_type = ctrl->adr_type();
    #ifdef ASSERT
    if (!VMError::is_error_reported() && !Node::in_dump())
      assert(adr_type != nullptr, "source must have adr_type");
    #endif
    return adr_type;
  }
  assert(bottom_type()->base() != Type::Memory, "no other memories?");
  return nullptr;
}

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)");}

void ProjNode::dump_compact_spec(outputStream *st) const {
  for (DUIterator i = this->outs(); this->has_out(i); i++) {
    Node* o = this->out(i);
    if (not_a_node(o)) {
      st->print("[?]");
    } else if (o == nullptr) {
      st->print("[_]");
    } else {
      st->print("[%d]", o->_idx);
    }
  }
  st->print("#%d", _con);
}
#endif

//----------------------------check_con----------------------------------------
void ProjNode::check_con() const {
  Node* n = in(0);
  if (n == nullptr)    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");
}

//------------------------------Identity---------------------------------------
Node* ProjNode::Identity(PhaseGVN* phase) {
  if (in(0) != nullptr && in(0)->Opcode() == Op_Tuple) {
    // Jumping over Tuples: the i-th projection of a Tuple is the i-th input of the Tuple.
    return in(0)->in(_con);
  }

  CallStaticJavaNode* call = in(0)->isa_CallStaticJava();
  if (call != nullptr) {
    if (call->is_boxing_method() && call->method()->return_type()->is_inlinetype()) {
      // Boxing (for example, via Integer.valueOf(int))
      if (call->tf()->returns_inline_type_as_fields()) {
        if (_con == TypeFunc::Parms) {
          // Oop projection: Keep it to avoid re-buffering. If unused,
          // it will go away and enable removal of the boxing call.
          return this;
        } else if (_con == TypeFunc::Parms + 1) {
          // Field projection: Use unboxed input value
          return call->in(TypeFunc::Parms);
        }
        // The null marker projection is removed by ProjNode::proj_type.
      }
    } else if (call->is_unboxing_method() && _con == TypeFunc::Parms) {
      // Unboxing (for example, via Integer.intValue())
      // Use field value of boxed input value object
      if (call->method()->has_scalarized_args()) {
        return call->in(TypeFunc::Parms + 1);
      } else {
        Node* arg = call->in(TypeFunc::Parms);
        if (arg->is_InlineType()) {
          assert(!phase->type(arg)->maybe_null(), "missing receiver null check?");
          return arg->as_InlineType()->field_value(0);
        }
      }
    }
  }
  return this;
}

//------------------------------Value------------------------------------------
const Type* ProjNode::Value(PhaseGVN* phase) const {
  if (in(0) == nullptr) 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 uncommon trap call node if proj is for "proj->[region->..]call_uct"
// null otherwise
CallStaticJavaNode* ProjNode::is_uncommon_trap_proj(Deoptimization::DeoptReason reason) const {
  const int path_limit = 10;
  const Node* out = this;
  for (int ct = 0; ct < path_limit; ct++) {
    out = out->unique_ctrl_out_or_null();
    if (out == nullptr)
      return nullptr;
    if (out->is_CallStaticJava()) {
      CallStaticJavaNode* call = out->as_CallStaticJava();
      int req = call->uncommon_trap_request();
      if (req != 0) {
        Deoptimization::DeoptReason trap_reason = Deoptimization::trap_request_reason(req);
        if (trap_reason == reason || reason == Deoptimization::Reason_none) {
          return call;
        }
      }
      return nullptr; // don't do further after call
    }
    if (out->Opcode() != Op_Region)
      return nullptr;
  }
  return nullptr;
}

//-------------------------------is_uncommon_trap_if_pattern-------------------------
// Return uncommon trap call node for    "if(test)-> proj -> ...
//                                                 |
//                                                 V
//                                             other_proj->[region->..]call_uct"
// or null otherwise.
CallStaticJavaNode* ProjNode::is_uncommon_trap_if_pattern(Deoptimization::DeoptReason reason) const {
  Node* iff = in(0);
  if (!iff->is_If() || iff->outcnt() < 2) {
    // Not a projection of an If or variation of a dead If node.
    return nullptr;
  }
  return as_IfProj()->other_if_proj()->is_uncommon_trap_proj(reason);
}

NarrowMemProjNode::NarrowMemProjNode(InitializeNode* src, const TypePtr* adr_type)
  : ProjNode(src, TypeFunc::Memory), _adr_type(adr_type) {
  assert(Compile::current()->have_alias_type(adr_type), "alias index should have been allocated already");
  init_class_id(Class_NarrowMemProj);
}