jdk

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/*
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 * Copyright (c) 2014, 2023, Oracle and/or its affiliates. All rights reserved.
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 *
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 * This code is free software; you can redistribute it and/or modify it
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 * under the terms of the GNU General Public License version 2 only, as
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 * published by the Free Software Foundation.
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 *
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 * This code is distributed in the hope that it will be useful, but WITHOUT
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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
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 * version 2 for more details (a copy is included in the LICENSE file that
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 * accompanied this code).
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 *
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 * You should have received a copy of the GNU General Public License version
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 * 2 along with this work; if not, write to the Free Software Foundation,
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 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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 *
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 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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 * or visit www.oracle.com if you need additional information or have any
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 * questions.
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 *
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 */
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#include "precompiled.hpp"
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#include "opto/addnode.hpp"
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#include "opto/callnode.hpp"
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#include "opto/castnode.hpp"
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#include "opto/connode.hpp"
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#include "opto/matcher.hpp"
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#include "opto/phaseX.hpp"
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#include "opto/subnode.hpp"
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#include "opto/type.hpp"
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#include "castnode.hpp"
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#include "utilities/checkedCast.hpp"
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//=============================================================================
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// If input is already higher or equal to cast type, then this is an identity.
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Node* ConstraintCastNode::Identity(PhaseGVN* phase) {
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  if (_dependency == UnconditionalDependency) {
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    return this;
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  }
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  Node* dom = dominating_cast(phase, phase);
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  if (dom != nullptr) {
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    return dom;
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  }
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  return higher_equal_types(phase, in(1)) ? in(1) : this;
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}
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//------------------------------Value------------------------------------------
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// Take 'join' of input and cast-up type
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const Type* ConstraintCastNode::Value(PhaseGVN* phase) const {
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  if (in(0) && phase->type(in(0)) == Type::TOP) return Type::TOP;
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  const Type* in_type = phase->type(in(1));
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  const Type* ft = in_type->filter_speculative(_type);
57

58
  // Check if both _type and in_type had a speculative type, but for the just
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  // computed ft the speculative type was dropped.
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  if (ft->speculative() == nullptr &&
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      _type->speculative() != nullptr &&
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      in_type->speculative() != nullptr) {
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    // Speculative type may have disagreed between cast and input, and was
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    // dropped in filtering. Recompute so that ft can take speculative type
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    // of in_type. If we did not do it now, a subsequent ::Value call would
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    // do it, and violate idempotence of ::Value.
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    ft = in_type->filter_speculative(ft);
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  }
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#ifdef ASSERT
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  // Previous versions of this function had some special case logic,
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  // which is no longer necessary.  Make sure of the required effects.
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  switch (Opcode()) {
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    case Op_CastII:
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    {
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      if (in_type == Type::TOP) {
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        assert(ft == Type::TOP, "special case #1");
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      }
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      const Type* rt = in_type->join_speculative(_type);
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      if (rt->empty()) {
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        assert(ft == Type::TOP, "special case #2");
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      }
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      break;
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    }
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    case Op_CastPP:
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    if (in_type == TypePtr::NULL_PTR &&
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        _type->isa_ptr() && _type->is_ptr()->_ptr == TypePtr::NotNull) {
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      assert(ft == Type::TOP, "special case #3");
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      break;
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    }
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  }
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#endif //ASSERT
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  return ft;
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}
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//------------------------------Ideal------------------------------------------
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// Return a node which is more "ideal" than the current node.  Strip out
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// control copies
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Node *ConstraintCastNode::Ideal(PhaseGVN *phase, bool can_reshape) {
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  return (in(0) && remove_dead_region(phase, can_reshape)) ? this : nullptr;
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}
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uint ConstraintCastNode::hash() const {
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  return TypeNode::hash() + (int)_dependency + (_extra_types != nullptr ? _extra_types->hash() : 0);
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}
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bool ConstraintCastNode::cmp(const Node &n) const {
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  if (!TypeNode::cmp(n)) {
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    return false;
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  }
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  ConstraintCastNode& cast = (ConstraintCastNode&) n;
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  if (cast._dependency != _dependency) {
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    return false;
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  }
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  if (_extra_types == nullptr || cast._extra_types == nullptr) {
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    return _extra_types == cast._extra_types;
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  }
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  return _extra_types->eq(cast._extra_types);
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}
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uint ConstraintCastNode::size_of() const {
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  return sizeof(*this);
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}
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Node* ConstraintCastNode::make_cast_for_basic_type(Node* c, Node* n, const Type* t, DependencyType dependency, BasicType bt) {
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  switch(bt) {
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  case T_INT:
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    return new CastIINode(c, n, t, dependency);
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  case T_LONG:
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    return new CastLLNode(c, n, t, dependency);
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  default:
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    fatal("Bad basic type %s", type2name(bt));
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  }
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  return nullptr;
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}
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TypeNode* ConstraintCastNode::dominating_cast(PhaseGVN* gvn, PhaseTransform* pt) const {
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  if (_dependency == UnconditionalDependency) {
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    return nullptr;
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  }
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  Node* val = in(1);
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  Node* ctl = in(0);
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  int opc = Opcode();
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  if (ctl == nullptr) {
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    return nullptr;
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  }
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  // Range check CastIIs may all end up under a single range check and
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  // in that case only the narrower CastII would be kept by the code
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  // below which would be incorrect.
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  if (is_CastII() && as_CastII()->has_range_check()) {
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    return nullptr;
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  }
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  if (type()->isa_rawptr() && (gvn->type_or_null(val) == nullptr || gvn->type(val)->isa_oopptr())) {
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    return nullptr;
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  }
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  for (DUIterator_Fast imax, i = val->fast_outs(imax); i < imax; i++) {
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    Node* u = val->fast_out(i);
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    if (u != this &&
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        u->outcnt() > 0 &&
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        u->Opcode() == opc &&
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        u->in(0) != nullptr &&
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        higher_equal_types(gvn, u)) {
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      if (pt->is_dominator(u->in(0), ctl)) {
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        return u->as_Type();
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      }
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      if (is_CheckCastPP() && u->in(1)->is_Proj() && u->in(1)->in(0)->is_Allocate() &&
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          u->in(0)->is_Proj() && u->in(0)->in(0)->is_Initialize() &&
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          u->in(1)->in(0)->as_Allocate()->initialization() == u->in(0)->in(0)) {
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        // CheckCastPP following an allocation always dominates all
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        // use of the allocation result
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        return u->as_Type();
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      }
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    }
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  }
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  return nullptr;
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}
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bool ConstraintCastNode::higher_equal_types(PhaseGVN* phase, const Node* other) const {
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  const Type* t = phase->type(other);
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  if (!t->higher_equal_speculative(type())) {
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    return false;
183
  }
184
  if (_extra_types != nullptr) {
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    for (uint i = 0; i < _extra_types->cnt(); ++i) {
186
      if (!t->higher_equal_speculative(_extra_types->field_at(i))) {
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        return false;
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      }
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    }
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  }
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  return true;
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}
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#ifndef PRODUCT
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void ConstraintCastNode::dump_spec(outputStream *st) const {
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  TypeNode::dump_spec(st);
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  if (_extra_types != nullptr) {
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    st->print(" extra types: ");
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    _extra_types->dump_on(st);
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  }
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  if (_dependency != RegularDependency) {
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    st->print(" %s dependency", _dependency == StrongDependency ? "strong" : "unconditional");
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  }
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}
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#endif
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const Type* CastIINode::Value(PhaseGVN* phase) const {
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  const Type *res = ConstraintCastNode::Value(phase);
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  if (res == Type::TOP) {
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    return Type::TOP;
211
  }
212
  assert(res->isa_int(), "res must be int");
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  // Similar to ConvI2LNode::Value() for the same reasons
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  // see if we can remove type assertion after loop opts
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  // But here we have to pay extra attention:
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  // Do not narrow the type of range check dependent CastIINodes to
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  // avoid corruption of the graph if a CastII is replaced by TOP but
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  // the corresponding range check is not removed.
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  if (!_range_check_dependency) {
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    res = widen_type(phase, res, T_INT);
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  }
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  return res;
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}
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static Node* find_or_make_integer_cast(PhaseIterGVN* igvn, Node* parent, Node* control, const TypeInteger* type, ConstraintCastNode::DependencyType dependency, BasicType bt) {
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  Node* n = ConstraintCastNode::make_cast_for_basic_type(control, parent, type, dependency, bt);
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  Node* existing = igvn->hash_find_insert(n);
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  if (existing != nullptr) {
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    n->destruct(igvn);
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    return existing;
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  }
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  return igvn->register_new_node_with_optimizer(n);
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}
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Node *CastIINode::Ideal(PhaseGVN *phase, bool can_reshape) {
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  Node* progress = ConstraintCastNode::Ideal(phase, can_reshape);
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  if (progress != nullptr) {
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    return progress;
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  }
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  if (can_reshape && !_range_check_dependency && !phase->C->post_loop_opts_phase()) {
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    // makes sure we run ::Value to potentially remove type assertion after loop opts
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    phase->C->record_for_post_loop_opts_igvn(this);
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  }
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  if (!_range_check_dependency) {
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    return optimize_integer_cast(phase, T_INT);
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  }
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  return nullptr;
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}
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Node* CastIINode::Identity(PhaseGVN* phase) {
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  Node* progress = ConstraintCastNode::Identity(phase);
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  if (progress != this) {
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    return progress;
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  }
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  if (_range_check_dependency) {
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    if (phase->C->post_loop_opts_phase()) {
259
      return this->in(1);
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    } else {
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      phase->C->record_for_post_loop_opts_igvn(this);
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    }
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  }
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  return this;
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}
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bool CastIINode::cmp(const Node &n) const {
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  return ConstraintCastNode::cmp(n) && ((CastIINode&)n)._range_check_dependency == _range_check_dependency;
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}
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uint CastIINode::size_of() const {
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  return sizeof(*this);
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}
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#ifndef PRODUCT
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void CastIINode::dump_spec(outputStream* st) const {
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  ConstraintCastNode::dump_spec(st);
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  if (_range_check_dependency) {
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    st->print(" range check dependency");
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  }
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}
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#endif
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284
CastIINode* CastIINode::pin_array_access_node() const {
285
  assert(_dependency == RegularDependency, "already pinned");
286
  if (has_range_check()) {
287
    return new CastIINode(in(0), in(1), bottom_type(), StrongDependency, has_range_check());
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  }
289
  return nullptr;
290
}
291

292

293
const Type* CastLLNode::Value(PhaseGVN* phase) const {
294
  const Type* res = ConstraintCastNode::Value(phase);
295
  if (res == Type::TOP) {
296
    return Type::TOP;
297
  }
298
  assert(res->isa_long(), "res must be long");
299

300
  return widen_type(phase, res, T_LONG);
301
}
302

303
Node* CastLLNode::Ideal(PhaseGVN* phase, bool can_reshape) {
304
  Node* progress = ConstraintCastNode::Ideal(phase, can_reshape);
305
  if (progress != nullptr) {
306
    return progress;
307
  }
308
  if (!phase->C->post_loop_opts_phase()) {
309
    // makes sure we run ::Value to potentially remove type assertion after loop opts
310
    phase->C->record_for_post_loop_opts_igvn(this);
311
  }
312
  // transform (CastLL (ConvI2L ..)) into (ConvI2L (CastII ..)) if the type of the CastLL is narrower than the type of
313
  // the ConvI2L.
314
  Node* in1 = in(1);
315
  if (in1 != nullptr && in1->Opcode() == Op_ConvI2L) {
316
    const Type* t = Value(phase);
317
    const Type* t_in = phase->type(in1);
318
    if (t != Type::TOP && t_in != Type::TOP) {
319
      const TypeLong* tl = t->is_long();
320
      const TypeLong* t_in_l = t_in->is_long();
321
      assert(tl->_lo >= t_in_l->_lo && tl->_hi <= t_in_l->_hi, "CastLL type should be narrower than or equal to the type of its input");
322
      assert((tl != t_in_l) == (tl->_lo > t_in_l->_lo || tl->_hi < t_in_l->_hi), "if type differs then this nodes's type must be narrower");
323
      if (tl != t_in_l) {
324
        const TypeInt* ti = TypeInt::make(checked_cast<jint>(tl->_lo), checked_cast<jint>(tl->_hi), tl->_widen);
325
        Node* castii = phase->transform(new CastIINode(in(0), in1->in(1), ti));
326
        Node* convi2l = in1->clone();
327
        convi2l->set_req(1, castii);
328
        return convi2l;
329
      }
330
    }
331
  }
332
  return optimize_integer_cast(phase, T_LONG);
333
}
334

335
//------------------------------Value------------------------------------------
336
// Take 'join' of input and cast-up type, unless working with an Interface
337
const Type* CheckCastPPNode::Value(PhaseGVN* phase) const {
338
  if( in(0) && phase->type(in(0)) == Type::TOP ) return Type::TOP;
339

340
  const Type *inn = phase->type(in(1));
341
  if( inn == Type::TOP ) return Type::TOP;  // No information yet
342

343
  if (inn->isa_oopptr() && _type->isa_oopptr()) {
344
    return ConstraintCastNode::Value(phase);
345
  }
346

347
  const TypePtr *in_type = inn->isa_ptr();
348
  const TypePtr *my_type = _type->isa_ptr();
349
  const Type *result = _type;
350
  if (in_type != nullptr && my_type != nullptr) {
351
    TypePtr::PTR in_ptr = in_type->ptr();
352
    if (in_ptr == TypePtr::Null) {
353
      result = in_type;
354
    } else if (in_ptr != TypePtr::Constant) {
355
      result =  my_type->cast_to_ptr_type(my_type->join_ptr(in_ptr));
356
    }
357
  }
358

359
  return result;
360
}
361

362
//=============================================================================
363
//------------------------------Value------------------------------------------
364
const Type* CastX2PNode::Value(PhaseGVN* phase) const {
365
  const Type* t = phase->type(in(1));
366
  if (t == Type::TOP) return Type::TOP;
367
  if (t->base() == Type_X && t->singleton()) {
368
    uintptr_t bits = (uintptr_t) t->is_intptr_t()->get_con();
369
    if (bits == 0)   return TypePtr::NULL_PTR;
370
    return TypeRawPtr::make((address) bits);
371
  }
372
  return CastX2PNode::bottom_type();
373
}
374

375
//------------------------------Idealize---------------------------------------
376
static inline bool fits_in_int(const Type* t, bool but_not_min_int = false) {
377
  if (t == Type::TOP)  return false;
378
  const TypeX* tl = t->is_intptr_t();
379
  jint lo = min_jint;
380
  jint hi = max_jint;
381
  if (but_not_min_int)  ++lo;  // caller wants to negate the value w/o overflow
382
  return (tl->_lo >= lo) && (tl->_hi <= hi);
383
}
384

385
static inline Node* addP_of_X2P(PhaseGVN *phase,
386
                                Node* base,
387
                                Node* dispX,
388
                                bool negate = false) {
389
  if (negate) {
390
    dispX = phase->transform(new SubXNode(phase->MakeConX(0), dispX));
391
  }
392
  return new AddPNode(phase->C->top(),
393
                      phase->transform(new CastX2PNode(base)),
394
                      dispX);
395
}
396

397
Node *CastX2PNode::Ideal(PhaseGVN *phase, bool can_reshape) {
398
  // convert CastX2P(AddX(x, y)) to AddP(CastX2P(x), y) if y fits in an int
399
  int op = in(1)->Opcode();
400
  Node* x;
401
  Node* y;
402
  switch (op) {
403
    case Op_SubX:
404
    x = in(1)->in(1);
405
    // Avoid ideal transformations ping-pong between this and AddP for raw pointers.
406
    if (phase->find_intptr_t_con(x, -1) == 0)
407
    break;
408
    y = in(1)->in(2);
409
    if (fits_in_int(phase->type(y), true)) {
410
      return addP_of_X2P(phase, x, y, true);
411
    }
412
    break;
413
    case Op_AddX:
414
    x = in(1)->in(1);
415
    y = in(1)->in(2);
416
    if (fits_in_int(phase->type(y))) {
417
      return addP_of_X2P(phase, x, y);
418
    }
419
    if (fits_in_int(phase->type(x))) {
420
      return addP_of_X2P(phase, y, x);
421
    }
422
    break;
423
  }
424
  return nullptr;
425
}
426

427
//------------------------------Identity---------------------------------------
428
Node* CastX2PNode::Identity(PhaseGVN* phase) {
429
  if (in(1)->Opcode() == Op_CastP2X)  return in(1)->in(1);
430
  return this;
431
}
432

433
//=============================================================================
434
//------------------------------Value------------------------------------------
435
const Type* CastP2XNode::Value(PhaseGVN* phase) const {
436
  const Type* t = phase->type(in(1));
437
  if (t == Type::TOP) return Type::TOP;
438
  if (t->base() == Type::RawPtr && t->singleton()) {
439
    uintptr_t bits = (uintptr_t) t->is_rawptr()->get_con();
440
    return TypeX::make(bits);
441
  }
442
  return CastP2XNode::bottom_type();
443
}
444

445
Node *CastP2XNode::Ideal(PhaseGVN *phase, bool can_reshape) {
446
  return (in(0) && remove_dead_region(phase, can_reshape)) ? this : nullptr;
447
}
448

449
//------------------------------Identity---------------------------------------
450
Node* CastP2XNode::Identity(PhaseGVN* phase) {
451
  if (in(1)->Opcode() == Op_CastX2P)  return in(1)->in(1);
452
  return this;
453
}
454

455
Node* ConstraintCastNode::make_cast_for_type(Node* c, Node* in, const Type* type, DependencyType dependency,
456
                                             const TypeTuple* types) {
457
  if (type->isa_int()) {
458
    return new CastIINode(c, in, type, dependency, false, types);
459
  } else if (type->isa_long()) {
460
    return new CastLLNode(c, in, type, dependency, types);
461
  } else if (type->isa_float()) {
462
    return new CastFFNode(c, in, type, dependency, types);
463
  } else if (type->isa_double()) {
464
    return new CastDDNode(c, in, type, dependency, types);
465
  } else if (type->isa_vect()) {
466
    return new CastVVNode(c, in, type, dependency, types);
467
  } else if (type->isa_ptr()) {
468
    return new CastPPNode(c, in, type, dependency, types);
469
  }
470
  fatal("unreachable. Invalid cast type.");
471
  return nullptr;
472
}
473

474
Node* ConstraintCastNode::optimize_integer_cast(PhaseGVN* phase, BasicType bt) {
475
  PhaseIterGVN *igvn = phase->is_IterGVN();
476
  const TypeInteger* this_type = this->type()->is_integer(bt);
477
  Node* z = in(1);
478
  const TypeInteger* rx = nullptr;
479
  const TypeInteger* ry = nullptr;
480
  // Similar to ConvI2LNode::Ideal() for the same reasons
481
  if (Compile::push_thru_add(phase, z, this_type, rx, ry, bt, bt)) {
482
    if (igvn == nullptr) {
483
      // Postpone this optimization to iterative GVN, where we can handle deep
484
      // AddI chains without an exponential number of recursive Ideal() calls.
485
      phase->record_for_igvn(this);
486
      return nullptr;
487
    }
488
    int op = z->Opcode();
489
    Node* x = z->in(1);
490
    Node* y = z->in(2);
491

492
    Node* cx = find_or_make_integer_cast(igvn, x, in(0), rx, _dependency, bt);
493
    Node* cy = find_or_make_integer_cast(igvn, y, in(0), ry, _dependency, bt);
494
    if (op == Op_Add(bt)) {
495
      return AddNode::make(cx, cy, bt);
496
    } else {
497
      assert(op == Op_Sub(bt), "");
498
      return SubNode::make(cx, cy, bt);
499
    }
500
    return nullptr;
501
  }
502
  return nullptr;
503
}
504

505
const Type* ConstraintCastNode::widen_type(const PhaseGVN* phase, const Type* res, BasicType bt) const {
506
  if (!phase->C->post_loop_opts_phase()) {
507
    return res;
508
  }
509
  const TypeInteger* this_type = res->is_integer(bt);
510
  const TypeInteger* in_type = phase->type(in(1))->isa_integer(bt);
511
  if (in_type != nullptr &&
512
      (in_type->lo_as_long() != this_type->lo_as_long() ||
513
       in_type->hi_as_long() != this_type->hi_as_long())) {
514
    jlong lo1 = this_type->lo_as_long();
515
    jlong hi1 = this_type->hi_as_long();
516
    int w1 = this_type->_widen;
517
    if (lo1 >= 0) {
518
      // Keep a range assertion of >=0.
519
      lo1 = 0;        hi1 = max_signed_integer(bt);
520
    } else if (hi1 < 0) {
521
      // Keep a range assertion of <0.
522
      lo1 = min_signed_integer(bt); hi1 = -1;
523
    } else {
524
      lo1 = min_signed_integer(bt); hi1 = max_signed_integer(bt);
525
    }
526
    return TypeInteger::make(MAX2(in_type->lo_as_long(), lo1),
527
                             MIN2(in_type->hi_as_long(), hi1),
528
                             MAX2((int)in_type->_widen, w1), bt);
529
  }
530
  return res;
531
}
532