1 /*
2 * Copyright (c) 2015, 2019, 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 "memory/allocation.hpp"
29 #include "opto/addnode.hpp"
30 #include "opto/graphKit.hpp"
31 #include "opto/machnode.hpp"
32 #include "opto/memnode.hpp"
33 #include "opto/multnode.hpp"
34 #include "opto/node.hpp"
35
36 class PhaseGVN;
37 class MemoryGraphFixer;
38
39 class ShenandoahBarrierC2Support : public AllStatic {
40 private:
41 #ifdef ASSERT
42 enum verify_type {
43 ShenandoahLoad,
44 ShenandoahStore,
45 ShenandoahValue,
46 ShenandoahOopStore,
47 ShenandoahNone
48 };
49
50 static bool verify_helper(Node* in, Node_Stack& phis, VectorSet& visited, verify_type t, bool trace, Unique_Node_List& barriers_used);
51 static void report_verify_failure(const char* msg, Node* n1 = NULL, Node* n2 = NULL);
52 static void verify_raw_mem(RootNode* root);
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_heap_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_heap_stable(Node*& ctrl, Node* raw_mem, Node*& heap_stable_ctrl,
62 PhaseIdealLoop* phase);
63 static void call_lrb_stub(Node*& ctrl, Node*& val, Node* load_addr, Node*& result_mem, Node* raw_mem, bool is_native, PhaseIdealLoop* phase);
64 static Node* clone_null_check(Node*& c, Node* val, Node* unc_ctrl, PhaseIdealLoop* phase);
65 static void fix_null_check(Node* unc, Node* unc_ctrl, Node* new_unc_ctrl, Unique_Node_List& uses,
66 PhaseIdealLoop* phase);
67 static void in_cset_fast_test(Node*& ctrl, Node*& not_cset_ctrl, Node* val, Node* raw_mem, PhaseIdealLoop* phase);
68 static void move_heap_stable_test_out_of_loop(IfNode* iff, PhaseIdealLoop* phase);
69 static void merge_back_to_back_tests(Node* n, PhaseIdealLoop* phase);
70 static bool identical_backtoback_ifs(Node *n, PhaseIdealLoop* phase);
71 static void fix_ctrl(Node* barrier, Node* region, const MemoryGraphFixer& fixer, Unique_Node_List& uses, Unique_Node_List& uses_to_ignore, uint last, PhaseIdealLoop* phase);
72 static IfNode* find_unswitching_candidate(const IdealLoopTree *loop, PhaseIdealLoop* phase);
73
74 static Node* get_load_addr(PhaseIdealLoop* phase, VectorSet& visited, Node* lrb);
75 public:
76 static bool is_dominator(Node* d_c, Node* n_c, Node* d, Node* n, PhaseIdealLoop* phase);
77 static bool is_dominator_same_ctrl(Node* c, Node* d, Node* n, PhaseIdealLoop* phase);
78
79 static bool is_gc_state_load(Node* n);
80 static bool is_heap_stable_test(Node* iff);
81
82 static bool expand(Compile* C, PhaseIterGVN& igvn);
83 static void pin_and_expand(PhaseIdealLoop* phase);
84 static void optimize_after_expansion(VectorSet& visited, Node_Stack& nstack, Node_List& old_new, PhaseIdealLoop* phase);
85
86 #ifdef ASSERT
87 static void verify(RootNode* root);
88 #endif
89 };
90
91 class ShenandoahEnqueueBarrierNode : public Node {
92 public:
93 ShenandoahEnqueueBarrierNode(Node* val);
94
95 const Type *bottom_type() const;
96 const Type* Value(PhaseGVN* phase) const;
97 Node* Identity(PhaseGVN* phase);
98
99 int Opcode() const;
100
101 private:
102 enum { Needed, NotNeeded, MaybeNeeded };
103
104 static int needed(Node* n);
105 static Node* next(Node* n);
106 };
107
108 class MemoryGraphFixer : public ResourceObj {
109 private:
110 Node_List _memory_nodes;
111 int _alias;
112 PhaseIdealLoop* _phase;
113 bool _include_lsm;
114
115 void collect_memory_nodes();
116 Node* get_ctrl(Node* n) const;
117 Node* ctrl_or_self(Node* n) const;
118 bool mem_is_valid(Node* m, Node* c) const;
119 MergeMemNode* allocate_merge_mem(Node* mem, Node* rep_proj, Node* rep_ctrl) const;
120 MergeMemNode* clone_merge_mem(Node* u, Node* mem, Node* rep_proj, Node* rep_ctrl, DUIterator& i) const;
121 void fix_memory_uses(Node* mem, Node* replacement, Node* rep_proj, Node* rep_ctrl) const;
122 bool should_process_phi(Node* phi) const;
123 bool has_mem_phi(Node* region) const;
124
125 public:
126 MemoryGraphFixer(int alias, bool include_lsm, PhaseIdealLoop* phase) :
127 _alias(alias), _phase(phase), _include_lsm(include_lsm) {
128 assert(_alias != Compile::AliasIdxBot, "unsupported");
129 collect_memory_nodes();
130 }
131
132 Node* find_mem(Node* ctrl, Node* n) const;
133 void fix_mem(Node* ctrl, Node* region, Node* mem, Node* mem_for_ctrl, Node* mem_phi, Unique_Node_List& uses);
134 int alias() const { return _alias; }
135 };
136
137 class ShenandoahCompareAndSwapPNode : public CompareAndSwapPNode {
138 public:
139 ShenandoahCompareAndSwapPNode(Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord)
140 : CompareAndSwapPNode(c, mem, adr, val, ex, mem_ord) { }
141
142 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape) {
143 if (in(ExpectedIn) != NULL && phase->type(in(ExpectedIn)) == TypePtr::NULL_PTR) {
144 return new CompareAndSwapPNode(in(MemNode::Control), in(MemNode::Memory), in(MemNode::Address), in(MemNode::ValueIn), in(ExpectedIn), order());
145 }
146 return NULL;
147 }
148
149 virtual int Opcode() const;
150 };
151
152 class ShenandoahCompareAndSwapNNode : public CompareAndSwapNNode {
153 public:
154 ShenandoahCompareAndSwapNNode(Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord)
155 : CompareAndSwapNNode(c, mem, adr, val, ex, mem_ord) { }
156
157 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape) {
158 if (in(ExpectedIn) != NULL && phase->type(in(ExpectedIn)) == TypeNarrowOop::NULL_PTR) {
159 return new CompareAndSwapNNode(in(MemNode::Control), in(MemNode::Memory), in(MemNode::Address), in(MemNode::ValueIn), in(ExpectedIn), order());
160 }
161 return NULL;
162 }
163
164 virtual int Opcode() const;
165 };
166
167 class ShenandoahWeakCompareAndSwapPNode : public WeakCompareAndSwapPNode {
168 public:
169 ShenandoahWeakCompareAndSwapPNode(Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord)
170 : WeakCompareAndSwapPNode(c, mem, adr, val, ex, mem_ord) { }
171
172 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape) {
173 if (in(ExpectedIn) != NULL && phase->type(in(ExpectedIn)) == TypePtr::NULL_PTR) {
174 return new WeakCompareAndSwapPNode(in(MemNode::Control), in(MemNode::Memory), in(MemNode::Address), in(MemNode::ValueIn), in(ExpectedIn), order());
175 }
176 return NULL;
177 }
178
179 virtual int Opcode() const;
180 };
181
182 class ShenandoahWeakCompareAndSwapNNode : public WeakCompareAndSwapNNode {
183 public:
184 ShenandoahWeakCompareAndSwapNNode(Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord)
185 : WeakCompareAndSwapNNode(c, mem, adr, val, ex, mem_ord) { }
186
187 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape) {
188 if (in(ExpectedIn) != NULL && phase->type(in(ExpectedIn)) == TypeNarrowOop::NULL_PTR) {
189 return new WeakCompareAndSwapNNode(in(MemNode::Control), in(MemNode::Memory), in(MemNode::Address), in(MemNode::ValueIn), in(ExpectedIn), order());
190 }
191 return NULL;
192 }
193
194 virtual int Opcode() const;
195 };
196
197 class ShenandoahCompareAndExchangePNode : public CompareAndExchangePNode {
198 public:
199 ShenandoahCompareAndExchangePNode(Node *c, Node *mem, Node *adr, Node *val, Node *ex, const TypePtr* at, const Type* t, MemNode::MemOrd mem_ord)
200 : CompareAndExchangePNode(c, mem, adr, val, ex, at, t, mem_ord) { }
201
202 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape) {
203 if (in(ExpectedIn) != NULL && phase->type(in(ExpectedIn)) == TypePtr::NULL_PTR) {
204 return new CompareAndExchangePNode(in(MemNode::Control), in(MemNode::Memory), in(MemNode::Address), in(MemNode::ValueIn), in(ExpectedIn), adr_type(), bottom_type(), order());
205 }
206 return NULL;
207 }
208
209 virtual int Opcode() const;
210 };
211
212 class ShenandoahCompareAndExchangeNNode : public CompareAndExchangeNNode {
213 public:
214 ShenandoahCompareAndExchangeNNode(Node *c, Node *mem, Node *adr, Node *val, Node *ex, const TypePtr* at, const Type* t, MemNode::MemOrd mem_ord)
215 : CompareAndExchangeNNode(c, mem, adr, val, ex, at, t, mem_ord) { }
216
217 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape) {
218 if (in(ExpectedIn) != NULL && phase->type(in(ExpectedIn)) == TypeNarrowOop::NULL_PTR) {
219 return new CompareAndExchangeNNode(in(MemNode::Control), in(MemNode::Memory), in(MemNode::Address), in(MemNode::ValueIn), in(ExpectedIn), adr_type(), bottom_type(), order());
220 }
221 return NULL;
222 }
223
224 virtual int Opcode() const;
225 };
226
227 class ShenandoahLoadReferenceBarrierNode : public Node {
228 public:
229 enum {
230 Control,
231 ValueIn
232 };
233
234 private:
235 bool _native;
236
237 public:
238 ShenandoahLoadReferenceBarrierNode(Node* ctrl, Node* val, bool native);
239
240 bool is_native() const;
241 virtual int Opcode() const;
242 virtual const Type* bottom_type() const;
243 virtual const Type* Value(PhaseGVN* phase) const;
244 virtual const class TypePtr *adr_type() const { return TypeOopPtr::BOTTOM; }
245 virtual uint match_edge(uint idx) const {
246 return idx >= ValueIn;
247 }
248 virtual uint ideal_reg() const { return Op_RegP; }
249
250 virtual Node* Identity(PhaseGVN* phase);
251
252 virtual uint size_of() const;
253 virtual uint hash() const;
254 virtual bool cmp( const Node &n ) const;
255
256 bool is_redundant();
257 CallStaticJavaNode* pin_and_expand_null_check(PhaseIterGVN& igvn);
258
259 private:
260 bool needs_barrier(PhaseGVN* phase, Node* n);
261 bool needs_barrier_impl(PhaseGVN* phase, Node* n, Unique_Node_List &visited);
262 };
263
264
265 #endif // SHARE_GC_SHENANDOAH_C2_SHENANDOAHSUPPORT_HPP