1 /*
2 * Copyright (c) 2016, 2026, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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5 * This code is free software; you can redistribute it and/or modify it
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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);
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);
72 // Store the field values to memory
73 void store(GraphKit* kit, Node* base, Node* ptr, bool immutable_memory, DecoratorSet decorators) const;
74
75 static InlineTypeNode* make_all_zero_impl(PhaseGVN& gvn, ciInlineKlass* vk);
76 static InlineTypeNode* make_from_oop_impl(GraphKit* kit, Node* oop, ciInlineKlass* vk);
77 static InlineTypeNode* make_null_impl(PhaseGVN& gvn, ciInlineKlass* vk, bool transform = true);
78 static InlineTypeNode* make_from_flat_impl(GraphKit* kit, ciInlineKlass* vk, Node* base, Node* ptr, bool atomic, bool immutable_memory,
79 bool null_free, bool trust_null_free_oop, DecoratorSet decorators);
80
81 public:
82 // Create with all-zero field values
83 static InlineTypeNode* make_all_zero(PhaseGVN& gvn, ciInlineKlass* vk);
84 // Create uninitialized
85 static InlineTypeNode* make_uninitialized(PhaseGVN& gvn, ciInlineKlass* vk, bool null_free = true);
86 // Create and initialize by loading the field values from an oop
87 static InlineTypeNode* make_from_oop(GraphKit* kit, Node* oop, ciInlineKlass* vk);
88 // Create and initialize by loading the field values from a flat field or array
89 static InlineTypeNode* make_from_flat(GraphKit* kit, ciInlineKlass* vk, Node* base, Node* ptr,
90 bool atomic, bool immutable_memory, bool null_free, DecoratorSet decorators);
91 static InlineTypeNode* make_from_flat_array(GraphKit* kit, ciInlineKlass* vk, Node* base, Node* idx);
92 // Create and initialize with the inputs or outputs of a MultiNode (method entry or call)
93 static InlineTypeNode* make_from_multi(GraphKit* kit, MultiNode* multi, ciInlineKlass* vk, uint& base_input, bool in, bool null_free = true);
94 // Create with null field values
95 static InlineTypeNode* make_null(PhaseGVN& gvn, ciInlineKlass* vk, bool transform = true);
96
97 // Support for control flow merges
98 bool has_phi_inputs(Node* region) const;
99 InlineTypeNode* clone_with_phis(PhaseGVN* gvn, Node* region, SafePointNode* map = nullptr, bool is_non_null = false, bool init_with_top = false);
100 InlineTypeNode* merge_with(PhaseGVN* gvn, const InlineTypeNode* other, int phi_index, bool transform);
101 void add_new_path(Node* region) const;
102
103 // Get oop for heap allocated inline type (may be TypePtr::NULL_PTR)
104 Node* get_oop() const { return in(Oop); }
105 void set_oop(PhaseGVN& gvn, Node* oop) { set_req_X(Oop, oop, &gvn); }
106 Node* get_null_marker() const { return in(NullMarker); }
107 void set_null_marker(PhaseGVN& gvn, Node* init) { set_req_X(NullMarker, init, &gvn); }
108 void set_null_marker(PhaseGVN& gvn) { set_null_marker(gvn, gvn.intcon(1)); }
109 Node* get_is_buffered() const { return in(IsBuffered); }
110 void set_is_buffered(PhaseGVN& gvn, bool buffered = true) { set_req_X(IsBuffered, gvn.intcon(buffered ? 1 : 0), &gvn); }
111
112 // Checks if the inline type fields are all set to zero
113 bool is_all_zero(PhaseGVN* gvn, bool flat = false) const;
114
115 // Inline type fields
116 uint field_count() const { return req() - Values; }
117 ciField* field(uint index) const;
118 Node* field_value(uint index) const;
119 Node* field_value_by_offset(int offset, bool recursive) const;
120 void set_field_value(uint index, Node* value);
121 void set_field_value_by_offset(int offset, Node* value);
122 uint field_index(int offset) const;
123
124 // Replace InlineTypeNodes in debug info at safepoints with SafePointScalarObjectNodes
125 void make_scalar_in_safepoints(PhaseIterGVN* igvn, bool allow_oop = true);
126 // Variant that allows to limit to a single safepoint. If nullptr is given, all safepoint uses will be considered.
127 void make_scalar_in_safepoints(PhaseIterGVN* igvn, bool allow_oop, SafePointNode* safepoint);
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
134 // Implementation of the substitutability check for acmp
135 static bool can_emit_substitutability_check(Node* lhs, Node* rhs);
136 static Node* emit_substitutability_check(GraphKit* kit, Node* lhs, Node* rhs);
137
138 // Allocates the inline type (if not yet allocated)
139 InlineTypeNode* buffer(GraphKit* kit, bool safe_for_replace = true);
140 bool is_allocated(PhaseGVN* phase) const;
141
142 void replace_call_results(GraphKit* kit, CallNode* call, Compile* C) const;
143 void replace_field_projs(Compile* C, CallNode* call, uint& proj_idx) const;
144
145 // Allocate all non-flat inline type fields
146 InlineTypeNode* allocate_fields(GraphKit* kit);
147
148 Node* tagged_klass(PhaseGVN& gvn) const {
149 return tagged_klass(inline_klass(), gvn);
150 }
151
152 static Node* tagged_klass(ciInlineKlass* vk, PhaseGVN& gvn);
153 // Pass inline type as fields at a call or return
154 void pass_fields(GraphKit* kit, Node* n, uint& base_input, bool in, bool null_free = true, bool root = false);
155
156 // Allocation optimizations
157 void remove_redundant_allocations(PhaseIdealLoop* phase) const;
158
159 InlineTypeNode* clone_if_required(PhaseGVN* gvn, SafePointNode* map, bool safe_for_replace = true);
160
161 virtual const Type* Value(PhaseGVN* phase) const;
162 virtual Node* Ideal(PhaseGVN* phase, bool can_reshape);
163 virtual int Opcode() const;
164 };
165
166 // Load from a flat element, the node produces 1 Proj output for each flattened field of the flat
167 // element. The order of the Proj node is the same as that of _vk->_nonstatic_fields, and the null
168 // marker if existing will be the last Proj output. This node acts as if the load happens
169 // atomically and will be expanded to loading the whole payload and extracting the flattened fields
170 // from the loaded payload. In special cases, such as when the object from which this load reads
171 // does not escape, this node can be expanded to multiple loads from each flattened field.
172 // This node allows us to replace its results with the value from a matching store because the
173 // payload value cannot be directly propagated if it contains oops. This effect, in turn, allows
174 // objects with atomic flat fields to be scalar replaced.
175 class LoadFlatNode final : public SafePointNode {
176 private:
177 ciInlineKlass* _vk;
178 const TypeTuple* _type;
179 bool _null_free;
180 DecoratorSet _decorators;
181
182 uint size_of() const override { return sizeof(*this); }
183
184 public:
185 static InlineTypeNode* load(GraphKit* kit, ciInlineKlass* vk, Node* base, Node* ptr, bool null_free, bool trust_null_free_oop, DecoratorSet decorators);
186 Node* base() const { return in(TypeFunc::Parms); }
187 Node* ptr() const { return in(TypeFunc::Parms + 1); }
188 bool expand_constant(PhaseIterGVN& igvn, ciInstance* inst) const;
189 bool expand_non_atomic(PhaseIterGVN& igvn) const;
190 void expand_atomic(PhaseIterGVN& igvn) const;
191
192 int Opcode() const override;
193 const Type* bottom_type() const override { return _type; }
194 Node* Ideal(PhaseGVN* phase, bool can_reshape) override { return nullptr; }
195 Node* Identity(PhaseGVN* phase) override { return this; }
196 const Type* Value(PhaseGVN* phase) const override;
197
198 private:
199 LoadFlatNode(ciInlineKlass* vk, const TypeTuple* type, bool null_free, DecoratorSet decorators)
200 : SafePointNode(TypeFunc::Parms + 2, nullptr, TypePtr::BOTTOM), _vk(vk), _type(type), _null_free(null_free), _decorators(decorators) {
201 init_class_id(Class_LoadFlat);
202 Compile::current()->add_flat_access(this);
203 }
204
205 static void collect_field_types(ciInlineKlass* vk, const Type** field_types, int idx, int limit, bool null_free, bool trust_null_free_oop);
206 InlineTypeNode* collect_projs(GraphKit* kit, ciInlineKlass* vk, int proj_con, bool null_free);
207 void expand_projs_atomic(PhaseIterGVN& gvn, Node* ctrl, Node* payload) const;
208 static Node* get_payload_value(PhaseIterGVN& igvn, Node* ctrl, BasicType payload_bt, Node* payload, const Type* value_type, BasicType value_bt, int offset);
209 };
210
211 // Store an InlineTypeNode to a flat element, the store acts as if it is atomic. Similar to
212 // LoadFlatNode, this node is expanded to storing a payload created from the field values of the
213 // InlineTypeNode, and under special circumstances, when there is no racing access to the field,
214 // this node can be expanded to multiple stores to each flattened field.
215 // The purposes of this node complement those of LoadFlatNode.
216 class StoreFlatNode final : public SafePointNode {
217 private:
218 bool _null_free;
219 DecoratorSet _decorators;
220
221 uint size_of() const override { return sizeof(*this); }
222
223 public:
224 static void store(GraphKit* kit, Node* base, Node* ptr, InlineTypeNode* value, bool null_free, DecoratorSet decorators);
225 Node* base() const { return in(TypeFunc::Parms); }
226 Node* ptr() const { return in(TypeFunc::Parms + 1); }
227 InlineTypeNode* value() const { return in(TypeFunc::Parms + 2)->as_InlineType(); }
228 bool expand_non_atomic(PhaseIterGVN& igvn) const;
229 void expand_atomic(PhaseIterGVN& igvn) const;
230
231 int Opcode() const override;
232 const Type* bottom_type() const override { return TypeTuple::MEMBAR; }
233 Node* Ideal(PhaseGVN* phase, bool can_reshape) override { return nullptr; }
234 Node* Identity(PhaseGVN* phase) override { return this; }
235 const Type* Value(PhaseGVN* phase) const override;
236
237 private:
238 StoreFlatNode(bool null_free, DecoratorSet decorators)
239 : SafePointNode(TypeFunc::Parms + 3, nullptr, TypePtr::BOTTOM), _null_free(null_free), _decorators(decorators) {
240 init_class_id(Class_StoreFlat);
241 Compile::current()->add_flat_access(this);
242 }
243
244 static Node* convert_to_payload(PhaseIterGVN& igvn, Node* ctrl, InlineTypeNode* value, bool null_free, int& oop_off_1, int& oop_off_2);
245 static Node* set_payload_value(PhaseIterGVN& igvn, BasicType payload_bt, Node* payload, BasicType val_bt, Node* value, int offset);
246 };
247
248 #endif // SHARE_VM_OPTO_INLINETYPENODE_HPP