1 /*
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 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
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 24 
 25 #ifndef SHARE_VM_OPTO_INLINETYPENODE_HPP
 26 #define SHARE_VM_OPTO_INLINETYPENODE_HPP
 27 
 28 #include "ci/ciInlineKlass.hpp"
 29 #include "oops/accessDecorators.hpp"
 30 #include "opto/callnode.hpp"
 31 #include "opto/compile.hpp"
 32 #include "opto/loopnode.hpp"
 33 #include "opto/node.hpp"
 34 
 35 class GraphKit;
 36 
 37 //------------------------------InlineTypeNode-------------------------------------
 38 // Node representing an inline type in C2 IR
 39 class InlineTypeNode : public TypeNode {
 40 private:
 41   InlineTypeNode(ciInlineKlass* vk, Node* oop, bool null_free)
 42       : TypeNode(TypeInstPtr::make(null_free ? TypePtr::NotNull : TypePtr::BotPTR, vk), Values + vk->nof_declared_nonstatic_fields()) {
 43     init_class_id(Class_InlineType);
 44     init_req(Oop, oop);
 45     Compile::current()->add_inline_type(this);
 46   }
 47 
 48   enum { Control,    // Control input.
 49          Oop,        // Oop to heap allocated buffer.
 50          IsBuffered, // True if inline type is heap allocated (or nullptr), false otherwise.
 51          NullMarker, // Needs to be checked before using the field values.
 52                      // 0 => InlineType is null
 53                      // 1 => InlineType is non-null
 54                      // Can be dynamic value, not necessarily statically known
 55          Values      // Nodes corresponding to values of the inline type's fields.
 56                      // Nodes are connected in increasing order of the index of the field they correspond to.
 57   };
 58 
 59   // Get the klass defining the field layout of the inline type
 60   ciInlineKlass* inline_klass() const { return type()->inline_klass(); }
 61 
 62   void make_scalar_in_safepoint(PhaseIterGVN* igvn, Unique_Node_List& worklist, SafePointNode* sfpt) const;
 63   uint add_fields_to_safepoint(Unique_Node_List& worklist, SafePointNode* sfpt) const;
 64 
 65   // Checks if the inline type is loaded from memory and if so returns the oop
 66   Node* is_loaded(PhaseGVN* phase, ciInlineKlass* vk = nullptr, Node* base = nullptr, int holder_offset = 0) const;
 67 
 68   // Initialize the inline type fields with the inputs or outputs of a MultiNode
 69   void initialize_fields(GraphKit* kit, MultiNode* multi, uint& base_input, bool in, bool no_null_marker, Node* null_check_region, GrowableArray<ciType*>& visited);
 70   // Initialize the inline type by loading its field values from memory
 71   void load(GraphKit* kit, Node* base, Node* ptr, bool immutable_memory, bool trust_null_free_oop, DecoratorSet decorators, GrowableArray<ciType*>& visited);
 72   // Store the field values to memory
 73   void store(GraphKit* kit, Node* base, Node* ptr, bool immutable_memory, DecoratorSet decorators) const;
 74 
 75   InlineTypeNode* adjust_scalarization_depth_impl(GraphKit* kit, GrowableArray<ciType*>& visited);
 76 
 77   static InlineTypeNode* make_all_zero_impl(PhaseGVN& gvn, ciInlineKlass* vk, GrowableArray<ciType*>& visited);
 78   static InlineTypeNode* make_from_oop_impl(GraphKit* kit, Node* oop, ciInlineKlass* vk, GrowableArray<ciType*>& visited);
 79   static InlineTypeNode* make_null_impl(PhaseGVN& gvn, ciInlineKlass* vk, GrowableArray<ciType*>& visited, bool transform = true);
 80   static InlineTypeNode* make_from_flat_impl(GraphKit* kit, ciInlineKlass* vk, Node* base, Node* ptr, bool atomic, bool immutable_memory,
 81                                              bool null_free, bool trust_null_free_oop, DecoratorSet decorators, GrowableArray<ciType*>& visited);
 82 
 83 public:
 84   // Create with all-zero field values
 85   static InlineTypeNode* make_all_zero(PhaseGVN& gvn, ciInlineKlass* vk);
 86   // Create uninitialized
 87   static InlineTypeNode* make_uninitialized(PhaseGVN& gvn, ciInlineKlass* vk, bool null_free = true);
 88   // Create and initialize by loading the field values from an oop
 89   static InlineTypeNode* make_from_oop(GraphKit* kit, Node* oop, ciInlineKlass* vk);
 90   // Create and initialize by loading the field values from a flat field or array
 91   static InlineTypeNode* make_from_flat(GraphKit* kit, ciInlineKlass* vk, Node* base, Node* ptr,
 92                                         bool atomic, bool immutable_memory, bool null_free, DecoratorSet decorators);
 93   static InlineTypeNode* make_from_flat_array(GraphKit* kit, ciInlineKlass* vk, Node* base, Node* idx);
 94   // Create and initialize with the inputs or outputs of a MultiNode (method entry or call)
 95   static InlineTypeNode* make_from_multi(GraphKit* kit, MultiNode* multi, ciInlineKlass* vk, uint& base_input, bool in, bool null_free = true);
 96   // Create with null field values
 97   static InlineTypeNode* make_null(PhaseGVN& gvn, ciInlineKlass* vk, bool transform = true);
 98 
 99   // Support for control flow merges
100   bool has_phi_inputs(Node* region) const;
101   InlineTypeNode* clone_with_phis(PhaseGVN* gvn, Node* region, SafePointNode* map = nullptr, bool is_non_null = false, bool init_with_top = false);
102   InlineTypeNode* merge_with(PhaseGVN* gvn, const InlineTypeNode* other, int phi_index, bool transform);
103   void add_new_path(Node* region) const;
104 
105   // Get oop for heap allocated inline type (may be TypePtr::NULL_PTR)
106   Node* get_oop() const    { return in(Oop); }
107   void  set_oop(PhaseGVN& gvn, Node* oop) { set_req_X(Oop, oop, &gvn); }
108   Node* get_null_marker() const { return in(NullMarker); }
109   void  set_null_marker(PhaseGVN& gvn, Node* init) { set_req_X(NullMarker, init, &gvn); }
110   void  set_null_marker(PhaseGVN& gvn) { set_null_marker(gvn, gvn.intcon(1)); }
111   Node* get_is_buffered() const { return in(IsBuffered); }
112   void  set_is_buffered(PhaseGVN& gvn, bool buffered = true) { set_req_X(IsBuffered, gvn.intcon(buffered ? 1 : 0), &gvn); }
113 
114   // Checks if the inline type fields are all set to zero
115   bool is_all_zero(PhaseGVN* gvn, bool flat = false) const;
116 
117   // Inline type fields
118   uint          field_count() const { return req() - Values; }
119   ciField*      field(uint index) const;
120   Node*         field_value(uint index) const;
121   Node*         field_value_by_offset(int offset, bool recursive) const;
122   void      set_field_value(uint index, Node* value);
123   void      set_field_value_by_offset(int offset, Node* value);
124   uint          field_index(int offset) const;
125 
126   // Replace InlineTypeNodes in debug info at safepoints with SafePointScalarObjectNodes
127   void make_scalar_in_safepoints(PhaseIterGVN* igvn, bool allow_oop = true);
128 
129   // Store the inline type as a flat (headerless) representation
130   void store_flat(GraphKit* kit, Node* base, Node* ptr, bool atomic, bool immutable_memory, bool null_free, DecoratorSet decorators);
131   // Store the inline type as a flat (headerless) representation into an array
132   void store_flat_array(GraphKit* kit, Node* base, Node* idx);
133   // Make sure that inline type is fully scalarized
134   InlineTypeNode* adjust_scalarization_depth(GraphKit* kit);
135 
136   // Implementation of the substitutability check for acmp
137   bool can_emit_substitutability_check(Node* other) const;
138   void check_substitutability(PhaseIterGVN* igvn, RegionNode* region, Node* phi, Node** ctrl, Node* mem, Node* base, Node* other, bool flat = false) const;
139 
140   // Allocates the inline type (if not yet allocated)
141   InlineTypeNode* buffer(GraphKit* kit, bool safe_for_replace = true);
142   bool is_allocated(PhaseGVN* phase) const;
143 
144   void replace_call_results(GraphKit* kit, CallNode* call, Compile* C) const;
145   void replace_field_projs(Compile* C, CallNode* call, uint& proj_idx) const;
146 
147   // Allocate all non-flat inline type fields
148   InlineTypeNode* allocate_fields(GraphKit* kit);
149 
150   Node* tagged_klass(PhaseGVN& gvn) const {
151     return tagged_klass(inline_klass(), gvn);
152   }
153 
154   static Node* tagged_klass(ciInlineKlass* vk, PhaseGVN& gvn);
155   // Pass inline type as fields at a call or return
156   void pass_fields(GraphKit* kit, Node* n, uint& base_input, bool in, bool null_free = true, bool root = false);
157 
158   // Allocation optimizations
159   void remove_redundant_allocations(PhaseIdealLoop* phase) const;
160 
161   InlineTypeNode* clone_if_required(PhaseGVN* gvn, SafePointNode* map, bool safe_for_replace = true);
162 
163   virtual const Type* Value(PhaseGVN* phase) const;
164   virtual Node* Ideal(PhaseGVN* phase, bool can_reshape);
165   virtual int Opcode() const;
166 };
167 
168 // Load from a flat element, the node produces 1 Proj output for each flattened field of the flat
169 // element. The order of the Proj node is the same as that of _vk->_nonstatic_fields, and the null
170 // marker if existing will be the last Proj output. This node acts as if the load happens
171 // atomically and will be expanded to loading the whole payload and extracting the flattened fields
172 // from the loaded payload. In special cases, such as when the object from which this load reads
173 // does not escape, this node can be expanded to multiple loads from each flattened field.
174 // This node allows us to replace its results with the value from a matching store because the
175 // payload value cannot be directly propagated if it contains oops. This effect, in turn, allows
176 // objects with atomic flat fields to be scalar replaced.
177 class LoadFlatNode final : public SafePointNode {
178 private:
179   ciInlineKlass* _vk;
180   const TypeTuple* _type;
181   bool _null_free;
182   DecoratorSet _decorators;
183 
184   uint size_of() const override { return sizeof(*this); }
185 
186 public:
187   static InlineTypeNode* load(GraphKit* kit, ciInlineKlass* vk, Node* base, Node* ptr, bool null_free, bool trust_null_free_oop, DecoratorSet decorators);
188   Node* base() const { return in(TypeFunc::Parms); }
189   Node* ptr() const { return in(TypeFunc::Parms + 1); }
190   bool expand_constant(PhaseIterGVN& igvn, ciInstance* inst) const;
191   bool expand_non_atomic(PhaseIterGVN& igvn) const;
192   void expand_atomic(PhaseIterGVN& igvn) const;
193 
194   int Opcode() const override;
195   const Type* bottom_type() const override { return _type; }
196   Node* Ideal(PhaseGVN* phase, bool can_reshape) override { return nullptr; }
197   Node* Identity(PhaseGVN* phase) override { return this; }
198   const Type* Value(PhaseGVN* phase) const override;
199 
200 private:
201   LoadFlatNode(ciInlineKlass* vk, const TypeTuple* type, bool null_free, DecoratorSet decorators)
202     : SafePointNode(TypeFunc::Parms + 2, nullptr, TypePtr::BOTTOM), _vk(vk), _type(type), _null_free(null_free), _decorators(decorators) {
203     init_class_id(Class_LoadFlat);
204     Compile::current()->add_flat_access(this);
205   }
206 
207   static void collect_field_types(ciInlineKlass* vk, const Type** field_types, int idx, int limit, bool null_free, bool trust_null_free_oop);
208   InlineTypeNode* collect_projs(GraphKit* kit, ciInlineKlass* vk, int proj_con, bool null_free);
209   void expand_projs_atomic(PhaseIterGVN& gvn, Node* ctrl, Node* payload) const;
210   static Node* get_payload_value(PhaseIterGVN& igvn, Node* ctrl, BasicType payload_bt, Node* payload, const Type* value_type, BasicType value_bt, int offset);
211 };
212 
213 // Store an InlineTypeNode to a flat element, the store acts as if it is atomic. Similar to
214 // LoadFlatNode, this node is expanded to storing a payload created from the field values of the
215 // InlineTypeNode, and under special circumstances, when there is no racing access to the field,
216 // this node can be expanded to multiple stores to each flattened field.
217 // The purposes of this node complement those of LoadFlatNode.
218 class StoreFlatNode final : public SafePointNode {
219 private:
220   bool _null_free;
221   DecoratorSet _decorators;
222 
223   uint size_of() const override { return sizeof(*this); }
224 
225 public:
226   static void store(GraphKit* kit, Node* base, Node* ptr, InlineTypeNode* value, bool null_free, DecoratorSet decorators);
227   Node* base() const { return in(TypeFunc::Parms); }
228   Node* ptr() const { return in(TypeFunc::Parms + 1); }
229   InlineTypeNode* value() const { return in(TypeFunc::Parms + 2)->as_InlineType(); }
230   bool expand_non_atomic(PhaseIterGVN& igvn) const;
231   void expand_atomic(PhaseIterGVN& igvn) const;
232 
233   int Opcode() const override;
234   const Type* bottom_type() const override { return TypeTuple::MEMBAR; }
235   Node* Ideal(PhaseGVN* phase, bool can_reshape) override { return nullptr; }
236   Node* Identity(PhaseGVN* phase) override { return this; }
237   const Type* Value(PhaseGVN* phase) const override;
238 
239 private:
240   StoreFlatNode(bool null_free, DecoratorSet decorators)
241     : SafePointNode(TypeFunc::Parms + 3, nullptr, TypePtr::BOTTOM), _null_free(null_free), _decorators(decorators) {
242     init_class_id(Class_StoreFlat);
243     Compile::current()->add_flat_access(this);
244   }
245 
246   static Node* convert_to_payload(PhaseIterGVN& igvn, Node* ctrl, InlineTypeNode* value, bool null_free, int& oop_off_1, int& oop_off_2);
247   static Node* set_payload_value(PhaseIterGVN& igvn, BasicType payload_bt, Node* payload, BasicType val_bt, Node* value, int offset);
248 };
249 
250 #endif // SHARE_VM_OPTO_INLINETYPENODE_HPP