src/hotspot/share/opto/castnode.hpp - toolchain/jdk/jdk21 - Git at Google

 /*
  * Copyright (c) 2014, 2023, 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_OPTO_CASTNODE_HPP
 #define SHARE_OPTO_CASTNODE_HPP

 #include "opto/node.hpp"
 #include "opto/opcodes.hpp"


 //------------------------------ConstraintCastNode-----------------------------
 // cast to a different range
 class ConstraintCastNode: public TypeNode {
 public:
   enum DependencyType {
     RegularDependency, // if cast doesn't improve input type, cast can be removed
     StrongDependency,  // leave cast in even if _type doesn't improve input type, can be replaced by stricter dominating cast if one exist
     UnconditionalDependency // leave cast in unconditionally
   };

   protected:
   const DependencyType _dependency;
   virtual bool cmp( const Node &n ) const;
   virtual uint size_of() const;
   virtual uint hash() const;    // Check the type
   const Type* widen_type(const PhaseGVN* phase, const Type* res, BasicType bt) const;

   private:
   // PhiNode::Ideal() transforms a Phi that merges a single uncasted value into a single cast pinned at the region.
   // The types of cast nodes eliminated as a consequence of this transformation are collected and stored here so the
   // type dependencies carried by the cast are known. The cast can then be eliminated if the type of its input is
   // narrower (or equal) than all the types it carries.
   const TypeTuple* _extra_types;

   public:
   ConstraintCastNode(Node* n, const Type* t, ConstraintCastNode::DependencyType dependency,
                      const TypeTuple* extra_types)
           : TypeNode(t,2), _dependency(dependency), _extra_types(extra_types) {
     init_class_id(Class_ConstraintCast);
     init_req(1, n);
   }
   virtual Node* Identity(PhaseGVN* phase);
   virtual const Type* Value(PhaseGVN* phase) const;
   virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
   virtual int Opcode() const;
   virtual uint ideal_reg() const = 0;
   virtual bool depends_only_on_test() const { return _dependency == RegularDependency; }
   bool carry_dependency() const { return _dependency != RegularDependency; }
   TypeNode* dominating_cast(PhaseGVN* gvn, PhaseTransform* pt) const;
   static Node* make_cast(int opcode, Node* c, Node* n, const Type* t, DependencyType dependency, const TypeTuple* extra_types);
   static Node* make(Node* c, Node *n, const Type *t, DependencyType dependency, BasicType bt);

 #ifndef PRODUCT
   virtual void dump_spec(outputStream *st) const;
 #endif

   static Node* make_cast_for_type(Node* c, Node* in, const Type* type, DependencyType dependency,
                                   const TypeTuple* types);

   Node* optimize_integer_cast(PhaseGVN* phase, BasicType bt);

   // Visit all non-cast uses of the node, bypassing ConstraintCasts.
   // Pattern: this (-> ConstraintCast)* -> non_cast
   // In other words: find all non_cast nodes such that
   // non_cast->uncast() == this.
   template <typename Callback>
   static void visit_uncasted_uses(const Node* n, Callback callback) {
     ResourceMark rm;
     Unique_Node_List internals;
     internals.push((Node*)n); // start traversal
     for (uint j = 0; j < internals.size(); ++j) {
       Node* internal = internals.at(j); // for every internal
       for (DUIterator_Fast kmax, k = internal->fast_outs(kmax); k < kmax; k++) {
         Node* internal_use = internal->fast_out(k);
         if (internal_use->is_ConstraintCast()) {
           internals.push(internal_use); // traverse this cast also
         } else {
           callback(internal_use);
         }
       }
     }
   }

   bool higher_equal_types(PhaseGVN* phase, const Node* other) const;

   int extra_types_count() const {
     return _extra_types == nullptr ? 0 : _extra_types->cnt();
   }

   const Type* extra_type_at(int i) const {
     return _extra_types->field_at(i);
   }
 };

 //------------------------------CastIINode-------------------------------------
 // cast integer to integer (different range)
 class CastIINode: public ConstraintCastNode {
   protected:
   // Is this node dependent on a range check?
   const bool _range_check_dependency;
   virtual bool cmp(const Node &n) const;
   virtual uint size_of() const;

   public:
   CastIINode(Node* n, const Type* t, DependencyType dependency = RegularDependency, bool range_check_dependency = false, const TypeTuple* types = nullptr)
     : ConstraintCastNode(n, t, dependency, types), _range_check_dependency(range_check_dependency) {
     init_class_id(Class_CastII);
   }
   CastIINode(Node* ctrl, Node* n, const Type* t, DependencyType dependency = RegularDependency, bool range_check_dependency = false)
     : ConstraintCastNode(n, t, dependency, nullptr), _range_check_dependency(range_check_dependency) {
     init_class_id(Class_CastII);
     init_req(0, ctrl);
   }
   virtual int Opcode() const;
   virtual uint ideal_reg() const { return Op_RegI; }
   virtual Node* Identity(PhaseGVN* phase);
   virtual const Type* Value(PhaseGVN* phase) const;
   virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
   const bool has_range_check() {
 #ifdef _LP64
     return _range_check_dependency;
 #else
     assert(!_range_check_dependency, "Should not have range check dependency");
     return false;
 #endif
   }

 #ifndef PRODUCT
   virtual void dump_spec(outputStream* st) const;
 #endif
 };

 class CastLLNode: public ConstraintCastNode {
 public:
   CastLLNode(Node* ctrl, Node* n, const Type* t, DependencyType dependency = RegularDependency)
     : ConstraintCastNode(n, t, dependency, nullptr) {
     init_class_id(Class_CastLL);
     init_req(0, ctrl);
   }
   CastLLNode(Node* n, const Type* t, DependencyType dependency = RegularDependency, const TypeTuple* types = nullptr)
           : ConstraintCastNode(n, t, dependency, types) {
     init_class_id(Class_CastLL);
   }

   virtual const Type* Value(PhaseGVN* phase) const;
   virtual Node* Ideal(PhaseGVN* phase, bool can_reshape);
   virtual int Opcode() const;
   virtual uint ideal_reg() const { return Op_RegL; }
 };

 class CastFFNode: public ConstraintCastNode {
 public:
   CastFFNode(Node* n, const Type* t, DependencyType dependency = RegularDependency, const TypeTuple* types = nullptr)
           : ConstraintCastNode(n, t, dependency, types) {
     init_class_id(Class_CastFF);
   }
   virtual int Opcode() const;
   virtual uint ideal_reg() const { return in(1)->ideal_reg(); }
 };

 class CastDDNode: public ConstraintCastNode {
 public:
   CastDDNode(Node* n, const Type* t, DependencyType dependency = RegularDependency, const TypeTuple* types = nullptr)
           : ConstraintCastNode(n, t, dependency, types) {
     init_class_id(Class_CastDD);
   }
   virtual int Opcode() const;
   virtual uint ideal_reg() const { return in(1)->ideal_reg(); }
 };

 class CastVVNode: public ConstraintCastNode {
 public:
   CastVVNode(Node* n, const Type* t, DependencyType dependency = RegularDependency, const TypeTuple* types = nullptr)
           : ConstraintCastNode(n, t, dependency, types) {
     init_class_id(Class_CastVV);
   }
   virtual int Opcode() const;
   virtual uint ideal_reg() const { return in(1)->ideal_reg(); }
 };


 //------------------------------CastPPNode-------------------------------------
 // cast pointer to pointer (different type)
 class CastPPNode: public ConstraintCastNode {
   public:
   CastPPNode (Node *n, const Type *t, DependencyType dependency = RegularDependency, const TypeTuple* types = nullptr)
     : ConstraintCastNode(n, t, dependency, types) {
   }
   virtual int Opcode() const;
   virtual uint ideal_reg() const { return Op_RegP; }
 };

 //------------------------------CheckCastPPNode--------------------------------
 // for _checkcast, cast pointer to pointer (different type), without JOIN,
 class CheckCastPPNode: public ConstraintCastNode {
   public:
   CheckCastPPNode(Node *c, Node *n, const Type *t, DependencyType dependency = RegularDependency, const TypeTuple* types = nullptr)
     : ConstraintCastNode(n, t, dependency, types) {
     init_class_id(Class_CheckCastPP);
     init_req(0, c);
   }

   virtual const Type* Value(PhaseGVN* phase) const;
   virtual int   Opcode() const;
   virtual uint  ideal_reg() const { return Op_RegP; }
   bool depends_only_on_test() const { return !type()->isa_rawptr() && ConstraintCastNode::depends_only_on_test(); }
  };


 //------------------------------CastX2PNode-------------------------------------
 // convert a machine-pointer-sized integer to a raw pointer
 class CastX2PNode : public Node {
   public:
   CastX2PNode( Node *n ) : Node(nullptr, n) {}
   virtual int Opcode() const;
   virtual const Type* Value(PhaseGVN* phase) const;
   virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
   virtual Node* Identity(PhaseGVN* phase);
   virtual uint ideal_reg() const { return Op_RegP; }
   virtual const Type *bottom_type() const { return TypeRawPtr::BOTTOM; }
 };

 //------------------------------CastP2XNode-------------------------------------
 // Used in both 32-bit and 64-bit land.
 // Used for card-marks and unsafe pointer math.
 class CastP2XNode : public Node {
   public:
   CastP2XNode( Node *ctrl, Node *n ) : Node(ctrl, n) {}
   virtual int Opcode() const;
   virtual const Type* Value(PhaseGVN* phase) const;
   virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
   virtual Node* Identity(PhaseGVN* phase);
   virtual uint ideal_reg() const { return Op_RegX; }
   virtual const Type *bottom_type() const { return TypeX_X; }
   // Return false to keep node from moving away from an associated card mark.
   virtual bool depends_only_on_test() const { return false; }
 };


 #endif // SHARE_OPTO_CASTNODE_HPP
	/*
	* Copyright (c) 2014, 2023, 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_OPTO_CASTNODE_HPP
	#define SHARE_OPTO_CASTNODE_HPP

	#include "opto/node.hpp"
	#include "opto/opcodes.hpp"


	//------------------------------ConstraintCastNode-----------------------------
	// cast to a different range
	class ConstraintCastNode: public TypeNode {
	public:
	enum DependencyType {
	RegularDependency, // if cast doesn't improve input type, cast can be removed
	StrongDependency, // leave cast in even if _type doesn't improve input type, can be replaced by stricter dominating cast if one exist
	UnconditionalDependency // leave cast in unconditionally
	};

	protected:
	const DependencyType _dependency;
	virtual bool cmp( const Node &n ) const;
	virtual uint size_of() const;
	virtual uint hash() const; // Check the type
	const Type* widen_type(const PhaseGVN* phase, const Type* res, BasicType bt) const;

	private:
	// PhiNode::Ideal() transforms a Phi that merges a single uncasted value into a single cast pinned at the region.
	// The types of cast nodes eliminated as a consequence of this transformation are collected and stored here so the
	// type dependencies carried by the cast are known. The cast can then be eliminated if the type of its input is
	// narrower (or equal) than all the types it carries.
	const TypeTuple* _extra_types;

	public:
	ConstraintCastNode(Node* n, const Type* t, ConstraintCastNode::DependencyType dependency,
	const TypeTuple* extra_types)
	: TypeNode(t,2), _dependency(dependency), _extra_types(extra_types) {
	init_class_id(Class_ConstraintCast);
	init_req(1, n);
	}
	virtual Node* Identity(PhaseGVN* phase);
	virtual const Type* Value(PhaseGVN* phase) const;
	virtual Node Ideal(PhaseGVN phase, bool can_reshape);
	virtual int Opcode() const;
	virtual uint ideal_reg() const = 0;
	virtual bool depends_only_on_test() const { return _dependency == RegularDependency; }
	bool carry_dependency() const { return _dependency != RegularDependency; }
	TypeNode* dominating_cast(PhaseGVN* gvn, PhaseTransform* pt) const;
	static Node* make_cast(int opcode, Node* c, Node* n, const Type* t, DependencyType dependency, const TypeTuple* extra_types);
	static Node* make(Node* c, Node n, const Type t, DependencyType dependency, BasicType bt);

	#ifndef PRODUCT
	virtual void dump_spec(outputStream *st) const;
	#endif

	static Node* make_cast_for_type(Node* c, Node* in, const Type* type, DependencyType dependency,
	const TypeTuple* types);

	Node* optimize_integer_cast(PhaseGVN* phase, BasicType bt);

	// Visit all non-cast uses of the node, bypassing ConstraintCasts.
	// Pattern: this (-> ConstraintCast)* -> non_cast
	// In other words: find all non_cast nodes such that
	// non_cast->uncast() == this.
	template <typename Callback>
	static void visit_uncasted_uses(const Node* n, Callback callback) {
	ResourceMark rm;
	Unique_Node_List internals;
	internals.push((Node*)n); // start traversal
	for (uint j = 0; j < internals.size(); ++j) {
	Node* internal = internals.at(j); // for every internal
	for (DUIterator_Fast kmax, k = internal->fast_outs(kmax); k < kmax; k++) {
	Node* internal_use = internal->fast_out(k);
	if (internal_use->is_ConstraintCast()) {
	internals.push(internal_use); // traverse this cast also
	} else {
	callback(internal_use);
	}
	}
	}
	}

	bool higher_equal_types(PhaseGVN* phase, const Node* other) const;

	int extra_types_count() const {
	return _extra_types == nullptr ? 0 : _extra_types->cnt();
	}

	const Type* extra_type_at(int i) const {
	return _extra_types->field_at(i);
	}
	};

	//------------------------------CastIINode-------------------------------------
	// cast integer to integer (different range)
	class CastIINode: public ConstraintCastNode {
	protected:
	// Is this node dependent on a range check?
	const bool _range_check_dependency;
	virtual bool cmp(const Node &n) const;
	virtual uint size_of() const;

	public:
	CastIINode(Node* n, const Type* t, DependencyType dependency = RegularDependency, bool range_check_dependency = false, const TypeTuple* types = nullptr)
	: ConstraintCastNode(n, t, dependency, types), _range_check_dependency(range_check_dependency) {
	init_class_id(Class_CastII);
	}
	CastIINode(Node* ctrl, Node* n, const Type* t, DependencyType dependency = RegularDependency, bool range_check_dependency = false)
	: ConstraintCastNode(n, t, dependency, nullptr), _range_check_dependency(range_check_dependency) {
	init_class_id(Class_CastII);
	init_req(0, ctrl);
	}
	virtual int Opcode() const;
	virtual uint ideal_reg() const { return Op_RegI; }
	virtual Node* Identity(PhaseGVN* phase);
	virtual const Type* Value(PhaseGVN* phase) const;
	virtual Node Ideal(PhaseGVN phase, bool can_reshape);
	const bool has_range_check() {
	#ifdef _LP64
	return _range_check_dependency;
	#else
	assert(!_range_check_dependency, "Should not have range check dependency");
	return false;
	#endif
	}

	#ifndef PRODUCT
	virtual void dump_spec(outputStream* st) const;
	#endif
	};

	class CastLLNode: public ConstraintCastNode {
	public:
	CastLLNode(Node* ctrl, Node* n, const Type* t, DependencyType dependency = RegularDependency)
	: ConstraintCastNode(n, t, dependency, nullptr) {
	init_class_id(Class_CastLL);
	init_req(0, ctrl);
	}
	CastLLNode(Node* n, const Type* t, DependencyType dependency = RegularDependency, const TypeTuple* types = nullptr)
	: ConstraintCastNode(n, t, dependency, types) {
	init_class_id(Class_CastLL);
	}

	virtual const Type* Value(PhaseGVN* phase) const;
	virtual Node* Ideal(PhaseGVN* phase, bool can_reshape);
	virtual int Opcode() const;
	virtual uint ideal_reg() const { return Op_RegL; }
	};

	class CastFFNode: public ConstraintCastNode {
	public:
	CastFFNode(Node* n, const Type* t, DependencyType dependency = RegularDependency, const TypeTuple* types = nullptr)
	: ConstraintCastNode(n, t, dependency, types) {
	init_class_id(Class_CastFF);
	}
	virtual int Opcode() const;
	virtual uint ideal_reg() const { return in(1)->ideal_reg(); }
	};

	class CastDDNode: public ConstraintCastNode {
	public:
	CastDDNode(Node* n, const Type* t, DependencyType dependency = RegularDependency, const TypeTuple* types = nullptr)
	: ConstraintCastNode(n, t, dependency, types) {
	init_class_id(Class_CastDD);
	}
	virtual int Opcode() const;
	virtual uint ideal_reg() const { return in(1)->ideal_reg(); }
	};

	class CastVVNode: public ConstraintCastNode {
	public:
	CastVVNode(Node* n, const Type* t, DependencyType dependency = RegularDependency, const TypeTuple* types = nullptr)
	: ConstraintCastNode(n, t, dependency, types) {
	init_class_id(Class_CastVV);
	}
	virtual int Opcode() const;
	virtual uint ideal_reg() const { return in(1)->ideal_reg(); }
	};


	//------------------------------CastPPNode-------------------------------------
	// cast pointer to pointer (different type)
	class CastPPNode: public ConstraintCastNode {
	public:
	CastPPNode (Node n, const Type t, DependencyType dependency = RegularDependency, const TypeTuple* types = nullptr)
	: ConstraintCastNode(n, t, dependency, types) {
	}
	virtual int Opcode() const;
	virtual uint ideal_reg() const { return Op_RegP; }
	};

	//------------------------------CheckCastPPNode--------------------------------
	// for _checkcast, cast pointer to pointer (different type), without JOIN,
	class CheckCastPPNode: public ConstraintCastNode {
	public:
	CheckCastPPNode(Node c, Node n, const Type t, DependencyType dependency = RegularDependency, const TypeTuple types = nullptr)
	: ConstraintCastNode(n, t, dependency, types) {
	init_class_id(Class_CheckCastPP);
	init_req(0, c);
	}

	virtual const Type* Value(PhaseGVN* phase) const;
	virtual int Opcode() const;
	virtual uint ideal_reg() const { return Op_RegP; }
	bool depends_only_on_test() const { return !type()->isa_rawptr() && ConstraintCastNode::depends_only_on_test(); }
	};


	//------------------------------CastX2PNode-------------------------------------
	// convert a machine-pointer-sized integer to a raw pointer
	class CastX2PNode : public Node {
	public:
	CastX2PNode( Node *n ) : Node(nullptr, n) {}
	virtual int Opcode() const;
	virtual const Type* Value(PhaseGVN* phase) const;
	virtual Node Ideal(PhaseGVN phase, bool can_reshape);
	virtual Node* Identity(PhaseGVN* phase);
	virtual uint ideal_reg() const { return Op_RegP; }
	virtual const Type *bottom_type() const { return TypeRawPtr::BOTTOM; }
	};

	//------------------------------CastP2XNode-------------------------------------
	// Used in both 32-bit and 64-bit land.
	// Used for card-marks and unsafe pointer math.
	class CastP2XNode : public Node {
	public:
	CastP2XNode( Node ctrl, Node n ) : Node(ctrl, n) {}
	virtual int Opcode() const;
	virtual const Type* Value(PhaseGVN* phase) const;
	virtual Node Ideal(PhaseGVN phase, bool can_reshape);
	virtual Node* Identity(PhaseGVN* phase);
	virtual uint ideal_reg() const { return Op_RegX; }
	virtual const Type *bottom_type() const { return TypeX_X; }
	// Return false to keep node from moving away from an associated card mark.
	virtual bool depends_only_on_test() const { return false; }
	};



	#endif // SHARE_OPTO_CASTNODE_HPP