1 /*
2 * Copyright (c) 2015, 2021, Red Hat, Inc. 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_GC_SHENANDOAH_C2_SHENANDOAHSUPPORT_HPP
26 #define SHARE_GC_SHENANDOAH_C2_SHENANDOAHSUPPORT_HPP
27
28 #include "gc/shenandoah/shenandoahBarrierSet.hpp"
29 #include "memory/allocation.hpp"
30 #include "opto/addnode.hpp"
31 #include "opto/graphKit.hpp"
32 #include "opto/machnode.hpp"
33 #include "opto/memnode.hpp"
34 #include "opto/multnode.hpp"
35 #include "opto/node.hpp"
36
37 class PhaseGVN;
38 class MemoryGraphFixer;
39
40 class ShenandoahBarrierC2Support : public AllStatic {
41 private:
42 #ifdef ASSERT
43 enum verify_type {
44 ShenandoahLoad,
45 ShenandoahStore,
46 ShenandoahValue,
47 ShenandoahOopStore,
48 ShenandoahNone
49 };
50
51 static bool verify_helper(Node* in, Node_Stack& phis, VectorSet& visited, verify_type t, bool trace, Unique_Node_List& barriers_used);
52 static void report_verify_failure(const char* msg, Node* n1 = nullptr, Node* n2 = nullptr);
53 #endif
54 static Node* dom_mem(Node* mem, Node* ctrl, int alias, Node*& mem_ctrl, PhaseIdealLoop* phase);
55 static Node* no_branches(Node* c, Node* dom, bool allow_one_proj, PhaseIdealLoop* phase);
56 static bool is_gc_state_test(Node* iff, int mask);
57 static bool has_safepoint_between(Node* start, Node* stop, PhaseIdealLoop *phase);
58 static Node* find_bottom_mem(Node* ctrl, PhaseIdealLoop* phase);
59 static void follow_barrier_uses(Node* n, Node* ctrl, Unique_Node_List& uses, PhaseIdealLoop* phase);
60 static void test_null(Node*& ctrl, Node* val, Node*& null_ctrl, PhaseIdealLoop* phase);
61 static void test_gc_state(Node*& ctrl, Node* raw_mem, Node*& heap_stable_ctrl,
62 PhaseIdealLoop* phase, int flags);
63 static void call_lrb_stub(Node*& ctrl, Node*& val, Node* load_addr,
64 DecoratorSet decorators, PhaseIdealLoop* phase);
65
66 static void collect_nodes_above_barrier(Unique_Node_List &nodes_above_barrier, PhaseIdealLoop* phase, Node* ctrl,
67 Node* init_raw_mem);
68
69 static void test_in_cset(Node*& ctrl, Node*& not_cset_ctrl, Node* val, Node* raw_mem, PhaseIdealLoop* phase);
70 static void fix_ctrl(Node* barrier, Node* region, const MemoryGraphFixer& fixer, Unique_Node_List& uses, Unique_Node_List& nodes_above_barrier, uint last, PhaseIdealLoop* phase);
71
72 static Node* get_load_addr(PhaseIdealLoop* phase, VectorSet& visited, Node* lrb);
73 public:
74 static bool is_dominator(Node* d_c, Node* n_c, Node* d, Node* n, PhaseIdealLoop* phase);
75 static bool is_dominator_same_ctrl(Node* c, Node* d, Node* n, PhaseIdealLoop* phase);
76
77 static bool is_gc_state_load(Node* n);
78 static bool is_heap_stable_test(Node* iff);
79
80 static bool expand(Compile* C, PhaseIterGVN& igvn);
81 static void pin_and_expand(PhaseIdealLoop* phase);
82
83 static void push_data_inputs_at_control(PhaseIdealLoop* phase, Node* n, Node* ctrl,
84 Unique_Node_List &wq);
85 static bool is_anti_dependent_load_at_control(PhaseIdealLoop* phase, Node* maybe_load, Node* store, Node* control);
86
87 static void maybe_push_anti_dependent_loads(PhaseIdealLoop* phase, Node* maybe_store, Node* control, Unique_Node_List &wq);
88 #ifdef ASSERT
89 static void verify(RootNode* root);
90 #endif
91 };
92
93 class MemoryGraphFixer : public ResourceObj {
94 private:
95 Node_List _memory_nodes;
96 int _alias;
97 PhaseIdealLoop* _phase;
98 bool _include_lsm;
99
100 void collect_memory_nodes();
101 Node* get_ctrl(Node* n) const;
102 Node* ctrl_or_self(Node* n) const;
103 bool mem_is_valid(Node* m, Node* c) const;
104 MergeMemNode* allocate_merge_mem(Node* mem, Node* rep_proj, Node* rep_ctrl) const;
105 MergeMemNode* clone_merge_mem(Node* u, Node* mem, Node* rep_proj, Node* rep_ctrl, DUIterator& i) const;
106 void fix_memory_uses(Node* mem, Node* replacement, Node* rep_proj, Node* rep_ctrl) const;
107 bool should_process_phi(Node* phi) const;
108 bool has_mem_phi(Node* region) const;
109
110 public:
111 MemoryGraphFixer(int alias, bool include_lsm, PhaseIdealLoop* phase) :
112 _alias(alias), _phase(phase), _include_lsm(include_lsm) {
113 assert(_alias != Compile::AliasIdxBot, "unsupported");
114 collect_memory_nodes();
115 }
116
117 Node* find_mem(Node* ctrl, Node* n) const;
118 void fix_mem(Node* ctrl, Node* region, Node* mem, Node* mem_for_ctrl, Node* mem_phi, Unique_Node_List& uses);
119 int alias() const { return _alias; }
120
121 Node* collect_memory_for_infinite_loop(const Node* in);
122
123 void record_new_ctrl(Node* ctrl, Node* region, Node* mem, Node* mem_for_ctrl);
124 };
125
126 class ShenandoahCompareAndSwapPNode : public CompareAndSwapPNode {
127 public:
128 ShenandoahCompareAndSwapPNode(Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord)
129 : CompareAndSwapPNode(c, mem, adr, val, ex, mem_ord) { }
130
131 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape) {
132 if (in(ExpectedIn) != nullptr && phase->type(in(ExpectedIn)) == TypePtr::NULL_PTR) {
133 return new CompareAndSwapPNode(in(MemNode::Control), in(MemNode::Memory), in(MemNode::Address), in(MemNode::ValueIn), in(ExpectedIn), order());
134 }
135 return nullptr;
136 }
137
138 virtual int Opcode() const;
139 };
140
141 class ShenandoahCompareAndSwapNNode : public CompareAndSwapNNode {
142 public:
143 ShenandoahCompareAndSwapNNode(Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord)
144 : CompareAndSwapNNode(c, mem, adr, val, ex, mem_ord) { }
145
146 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape) {
147 if (in(ExpectedIn) != nullptr && phase->type(in(ExpectedIn)) == TypeNarrowOop::NULL_PTR) {
148 return new CompareAndSwapNNode(in(MemNode::Control), in(MemNode::Memory), in(MemNode::Address), in(MemNode::ValueIn), in(ExpectedIn), order());
149 }
150 return nullptr;
151 }
152
153 virtual int Opcode() const;
154 };
155
156 class ShenandoahWeakCompareAndSwapPNode : public WeakCompareAndSwapPNode {
157 public:
158 ShenandoahWeakCompareAndSwapPNode(Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord)
159 : WeakCompareAndSwapPNode(c, mem, adr, val, ex, mem_ord) { }
160
161 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape) {
162 if (in(ExpectedIn) != nullptr && phase->type(in(ExpectedIn)) == TypePtr::NULL_PTR) {
163 return new WeakCompareAndSwapPNode(in(MemNode::Control), in(MemNode::Memory), in(MemNode::Address), in(MemNode::ValueIn), in(ExpectedIn), order());
164 }
165 return nullptr;
166 }
167
168 virtual int Opcode() const;
169 };
170
171 class ShenandoahWeakCompareAndSwapNNode : public WeakCompareAndSwapNNode {
172 public:
173 ShenandoahWeakCompareAndSwapNNode(Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord)
174 : WeakCompareAndSwapNNode(c, mem, adr, val, ex, mem_ord) { }
175
176 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape) {
177 if (in(ExpectedIn) != nullptr && phase->type(in(ExpectedIn)) == TypeNarrowOop::NULL_PTR) {
178 return new WeakCompareAndSwapNNode(in(MemNode::Control), in(MemNode::Memory), in(MemNode::Address), in(MemNode::ValueIn), in(ExpectedIn), order());
179 }
180 return nullptr;
181 }
182
183 virtual int Opcode() const;
184 };
185
186 class ShenandoahCompareAndExchangePNode : public CompareAndExchangePNode {
187 public:
188 ShenandoahCompareAndExchangePNode(Node *c, Node *mem, Node *adr, Node *val, Node *ex, const TypePtr* at, const Type* t, MemNode::MemOrd mem_ord)
189 : CompareAndExchangePNode(c, mem, adr, val, ex, at, t, mem_ord) { }
190
191 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape) {
192 if (in(ExpectedIn) != nullptr && phase->type(in(ExpectedIn)) == TypePtr::NULL_PTR) {
193 return new CompareAndExchangePNode(in(MemNode::Control), in(MemNode::Memory), in(MemNode::Address), in(MemNode::ValueIn), in(ExpectedIn), adr_type(), bottom_type(), order());
194 }
195 return nullptr;
196 }
197
198 virtual int Opcode() const;
199 };
200
201 class ShenandoahCompareAndExchangeNNode : public CompareAndExchangeNNode {
202 public:
203 ShenandoahCompareAndExchangeNNode(Node *c, Node *mem, Node *adr, Node *val, Node *ex, const TypePtr* at, const Type* t, MemNode::MemOrd mem_ord)
204 : CompareAndExchangeNNode(c, mem, adr, val, ex, at, t, mem_ord) { }
205
206 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape) {
207 if (in(ExpectedIn) != nullptr && phase->type(in(ExpectedIn)) == TypeNarrowOop::NULL_PTR) {
208 return new CompareAndExchangeNNode(in(MemNode::Control), in(MemNode::Memory), in(MemNode::Address), in(MemNode::ValueIn), in(ExpectedIn), adr_type(), bottom_type(), order());
209 }
210 return nullptr;
211 }
212
213 virtual int Opcode() const;
214 };
215
216 class ShenandoahLoadReferenceBarrierNode : public Node {
217 public:
218 enum {
219 Control,
220 ValueIn
221 };
222
223 private:
224 DecoratorSet _decorators;
225
226 public:
227 ShenandoahLoadReferenceBarrierNode(Node* ctrl, Node* val, DecoratorSet decorators);
228
229 DecoratorSet decorators() const;
230 virtual int Opcode() const;
231 virtual const Type* bottom_type() const;
232 virtual const Type* Value(PhaseGVN* phase) const;
233 virtual const class TypePtr *adr_type() const { return TypeOopPtr::BOTTOM; }
234 virtual uint match_edge(uint idx) const {
235 return idx >= ValueIn;
236 }
237 virtual uint ideal_reg() const { return Op_RegP; }
238
239 virtual Node* Identity(PhaseGVN* phase);
240
241 virtual uint size_of() const;
242 virtual uint hash() const;
243 virtual bool cmp( const Node &n ) const;
244
245 private:
246 bool needs_barrier(PhaseGVN* phase, Node* n);
247 bool needs_barrier_impl(PhaseGVN* phase, Node* n, Unique_Node_List &visited);
248 };
249
250
251 #endif // SHARE_GC_SHENANDOAH_C2_SHENANDOAHSUPPORT_HPP