1 /*
   2  * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #ifndef SHARE_VM_OPTO_VALUETYPENODE_HPP
  26 #define SHARE_VM_OPTO_VALUETYPENODE_HPP
  27 
  28 #include "opto/node.hpp"
  29 #include "opto/connode.hpp"
  30 
  31 class GraphKit;
  32 
  33 class ValueTypeBaseNode : public TypeNode {
  34 protected:
  35   ValueTypeBaseNode(const Type* t, int nb_fields)
  36     : TypeNode(t, nb_fields) {
  37     init_class_id(Class_ValueTypeBase);
  38   }
  39 
  40   enum { Control,   // Control input
  41          Oop,       // Oop of TypeValueTypePtr
  42          Values     // Nodes corresponding to values of the value type's fields.
  43                     // Nodes are connected in increasing order of the index of the field
  44                     // they correspond to. Field indeces are defined in ciValueKlass::_field_index_map.
  45   };
  46 
  47   virtual const TypeValueTypePtr* value_type_ptr() const = 0;
  48   // Get the klass defining the field layout of the value type
  49   virtual ciValueKlass* value_klass() const = 0;
  50   int make_scalar_in_safepoint(SafePointNode* sfpt, Node* root, PhaseGVN* gvn);
  51 
  52   static void make(PhaseGVN* gvn, Node* n, ValueTypeBaseNode* vt, ciValueKlass* base_vk, int base_offset, int base_input, bool in);
  53 
  54 public:
  55   // Support for control flow merges
  56   bool  has_phi_inputs(Node* region);
  57   ValueTypeBaseNode* clone_with_phis(PhaseGVN* gvn, Node* region);
  58   ValueTypeBaseNode* merge_with(PhaseGVN* gvn, const ValueTypeBaseNode* other, int pnum, bool transform);
  59 
  60   // Get oop for heap allocated value type (may be TypePtr::NULL_PTR)
  61   Node* get_oop() const    { return in(Oop); }
  62   void  set_oop(Node* oop) { set_req(Oop, oop); }
  63 
  64   // Value type fields
  65   uint          field_count() const { return req() - Values; }
  66   Node*         field_value(uint index) const;
  67   Node*         field_value_by_offset(int offset, bool recursive = false) const;
  68   void      set_field_value(uint index, Node* value);
  69   int           field_offset(uint index) const;
  70   ciType*       field_type(uint index) const;
  71 
  72   // Replace ValueTypeNodes in debug info at safepoints with SafePointScalarObjectNodes
  73   void make_scalar_in_safepoints(Node* root, PhaseGVN* gvn);
  74 
  75   void store_flattened(PhaseGVN* gvn, Node* ctl, MergeMemNode* mem, Node* base, ciValueKlass* holder, int holder_offset) const;
  76   void store(PhaseGVN* gvn, Node* ctl, MergeMemNode* mem, Node* base, ciValueKlass* holder = NULL, int holder_offset = 0) const;
  77 
  78   // Initialize the value type by loading its field values from memory
  79   void load(PhaseGVN& gvn, Node* mem, Node* base, Node* ptr, ciInstanceKlass* holder, int holder_offset = 0);
  80 
  81   void replace_call_results(Node* call, Compile* C);
  82 
  83   static Node* allocate(const Type* type,
  84                         Node*& ctl, Node*& mem, Node*& io,
  85                         Node* frameptr,
  86                         Node*& ex_ctl, Node*& ex_mem, Node*& ex_io,
  87                         JVMState* jvms, PhaseIterGVN *igvn);
  88 };
  89 
  90 //------------------------------ValueTypeNode-------------------------------------
  91 // Node representing a value type in C2 IR
  92 class ValueTypeNode : public ValueTypeBaseNode {
  93   friend class ValueTypeBaseNode;
  94 private:
  95   ValueTypeNode(const TypeValueType* t, Node* oop)
  96     : ValueTypeBaseNode(t, Values + t->value_klass()->nof_declared_nonstatic_fields()) {
  97     init_class_id(Class_ValueType);
  98     init_req(Oop, oop);
  99   }
 100 
 101   ValueTypeNode(const TypeValueType* t, Node* oop, int field_count)
 102     : ValueTypeBaseNode(t, Values + field_count) {
 103     init_class_id(Class_ValueType);
 104     init_req(Oop, oop);
 105   }
 106 
 107   // Checks if the value type is loaded from memory and if so returns the oop
 108   Node* is_loaded(PhaseGVN* phase, const TypeValueType* t, Node* base = NULL, int holder_offset = 0);
 109 
 110   const TypeValueTypePtr* value_type_ptr() const { return TypeValueTypePtr::make(bottom_type()->isa_valuetype()); }
 111   // Get the klass defining the field layout of the value type
 112   ciValueKlass* value_klass() const { return type()->is_valuetype()->value_klass(); }
 113 
 114 public:
 115   // Create a new ValueTypeNode with uninitialized values
 116   static ValueTypeNode* make(PhaseGVN& gvn, ciValueKlass* klass);
 117   // Create a new ValueTypeNode with default values
 118   static Node* make_default(PhaseGVN& gvn, ciValueKlass* vk);
 119   // Create a new ValueTypeNode and load its values from an oop
 120   static Node* make(PhaseGVN& gvn, Node* mem, Node* oop);
 121   // Create a new ValueTypeNode and load its values from a flattened value type field or array
 122   static Node* make(PhaseGVN& gvn, ciValueKlass* vk, Node* mem, Node* obj, Node* ptr, ciInstanceKlass* holder = NULL, int holder_offset = 0);
 123   // Create value type node from arguments at method entry and calls
 124   static Node* make(PhaseGVN& gvn, Node* n, ciValueKlass* vk, int base_input, bool in);
 125 
 126   // Store the value type as a flattened (headerless) representation
 127   void store_flattened(GraphKit* kit, Node* base, Node* ptr, ciInstanceKlass* holder = NULL, int holder_offset = 0) const;
 128   // Store the field values to memory
 129   void store(GraphKit* kit, Node* base, Node* ptr, ciInstanceKlass* holder, int holder_offset = 0) const;
 130 
 131   // Allocates the value type (if not yet allocated) and returns the oop
 132   Node* allocate(GraphKit* kit);
 133   bool  is_allocated(PhaseGVN* phase) const;
 134 
 135   Node* tagged_klass(PhaseGVN& gvn);
 136   void pass_klass(Node* n, uint pos, const GraphKit& kit);
 137   uint pass_fields(Node* call, int base_input, const GraphKit& kit, ciValueKlass* base_vk = NULL, int base_offset = 0);
 138 
 139   // Allocation optimizations
 140   void remove_redundant_allocations(PhaseIterGVN* igvn, PhaseIdealLoop* phase);
 141 
 142   virtual Node* Ideal(PhaseGVN* phase, bool can_reshape);
 143   virtual int Opcode() const;
 144 
 145 #ifndef PRODUCT
 146   virtual void dump_spec(outputStream* st) const;
 147 #endif
 148 };
 149 
 150 //------------------------------ValueTypePtrNode-------------------------------------
 151 // Node representing a value type as a pointer in C2 IR
 152 class ValueTypePtrNode : public ValueTypeBaseNode {
 153 private:
 154   ciValueKlass* value_klass() const { return type()->is_valuetypeptr()->value_type()->value_klass(); }
 155   const TypeValueTypePtr* value_type_ptr() const { return bottom_type()->isa_valuetypeptr(); }
 156 
 157   ValueTypePtrNode(ciValueKlass* vk, Compile* C)
 158     : ValueTypeBaseNode(TypeValueTypePtr::make(TypePtr::NotNull, vk), Values + vk->nof_declared_nonstatic_fields()) {
 159     init_class_id(Class_ValueTypePtr);
 160     C->add_value_type_ptr(this);
 161   }
 162 public:
 163 
 164   ValueTypePtrNode(ValueTypeNode* vt, Node* oop, Compile* C)
 165     : ValueTypeBaseNode(TypeValueTypePtr::make(vt->type()->is_valuetype())->cast_to_ptr_type(TypePtr::NotNull), vt->req()) {
 166     init_class_id(Class_ValueTypePtr);
 167     for (uint i = Oop+1; i < vt->req(); i++) {
 168       init_req(i, vt->in(i));
 169     }
 170     init_req(Oop, oop);
 171     C->add_value_type_ptr(this);
 172   }
 173 
 174   static ValueTypePtrNode* make(PhaseGVN* gvn, CheckCastPPNode* cast);
 175   static ValueTypePtrNode* make(PhaseGVN& gvn, Node* mem, Node* oop);
 176   virtual int Opcode() const;
 177 };
 178 
 179 #endif // SHARE_VM_OPTO_VALUETYPENODE_HPP