1 /*
2 * Copyright (c) 2015, 2018, Red Hat, Inc. All rights reserved.
3 *
4 * This code is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License version 2 only, as
6 * published by the Free Software Foundation.
7 *
8 * This code is distributed in the hope that it will be useful, but WITHOUT
9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
11 * version 2 for more details (a copy is included in the LICENSE file that
12 * accompanied this code).
13 *
14 * You should have received a copy of the GNU General Public License version
15 * 2 along with this work; if not, write to the Free Software Foundation,
16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
17 *
18 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
19 * or visit www.oracle.com if you need additional information or have any
20 * questions.
21 *
22 */
23
24 #ifndef SHARE_GC_SHENANDOAH_C2_SHENANDOAHSUPPORT_HPP
25 #define SHARE_GC_SHENANDOAH_C2_SHENANDOAHSUPPORT_HPP
26
27 #include "gc_implementation/shenandoah/shenandoahForwarding.hpp"
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 IdealLoopTree;
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 = NULL, Node* n2 = NULL);
53 public:
54 static void verify_raw_mem(RootNode* root);
55 private:
56 #endif
57 static Node* dom_mem(Node* mem, Node* ctrl, int alias, Node*& mem_ctrl, PhaseIdealLoop* phase);
58 static Node* no_branches(Node* c, Node* dom, bool allow_one_proj, PhaseIdealLoop* phase);
59 static bool is_heap_state_test(Node* iff, int mask);
60 static bool has_safepoint_between(Node* start, Node* stop, PhaseIdealLoop *phase);
61 static Node* find_bottom_mem(Node* ctrl, PhaseIdealLoop* phase);
62 static void follow_barrier_uses(Node* n, Node* ctrl, Unique_Node_List& uses, PhaseIdealLoop* phase);
63 static void test_null(Node*& ctrl, Node* val, Node*& null_ctrl, PhaseIdealLoop* phase);
64 static void test_heap_state(Node*& ctrl, Node* raw_mem, Node*& heap_stable_ctrl,
65 PhaseIdealLoop* phase, int flags);
66 static void call_lrb_stub(Node*& ctrl, Node*& val, Node*& result_mem, Node* raw_mem, PhaseIdealLoop* phase);
67 static Node* clone_null_check(Node*& c, Node* val, Node* unc_ctrl, PhaseIdealLoop* phase);
68 static void fix_null_check(Node* unc, Node* unc_ctrl, Node* new_unc_ctrl, Unique_Node_List& uses,
69 PhaseIdealLoop* phase);
70 static void in_cset_fast_test(Node*& ctrl, Node*& not_cset_ctrl, Node* val, Node* raw_mem, PhaseIdealLoop* phase);
71 static void move_heap_stable_test_out_of_loop(IfNode* iff, PhaseIdealLoop* phase);
72 static void merge_back_to_back_tests(Node* n, PhaseIdealLoop* phase);
73 static bool identical_backtoback_ifs(Node *n, PhaseIdealLoop* phase);
74 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);
75 static IfNode* find_unswitching_candidate(const IdealLoopTree *loop, PhaseIdealLoop* phase);
76
77 public:
78 static bool is_dominator(Node* d_c, Node* n_c, Node* d, Node* n, PhaseIdealLoop* phase);
79 static bool is_dominator_same_ctrl(Node* c, Node* d, Node* n, PhaseIdealLoop* phase);
80
81 static bool is_gc_state_load(Node* n);
82 static bool is_heap_stable_test(Node* iff);
83
84 static bool expand(Compile* C, PhaseIterGVN& igvn);
85 static void pin_and_expand(PhaseIdealLoop* phase);
86 static void optimize_after_expansion(VectorSet& visited, Node_Stack& nstack, Node_List& old_new, PhaseIdealLoop* phase);
87
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
122 class ShenandoahCompareAndSwapPNode : public CompareAndSwapPNode {
123 public:
124 ShenandoahCompareAndSwapPNode(Node *c, Node *mem, Node *adr, Node *val, Node *ex)
125 : CompareAndSwapPNode(c, mem, adr, val, ex) { }
126
127 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape) {
128 if (in(ExpectedIn) != NULL && phase->type(in(ExpectedIn)) == TypePtr::NULL_PTR) {
129 return new (phase->C) CompareAndSwapPNode(in(MemNode::Control), in(MemNode::Memory), in(MemNode::Address), in(MemNode::ValueIn), in(ExpectedIn));
130 }
131 return NULL;
132 }
133
134 virtual int Opcode() const;
135 };
136
137 class ShenandoahCompareAndSwapNNode : public CompareAndSwapNNode {
138 public:
139 ShenandoahCompareAndSwapNNode(Node *c, Node *mem, Node *adr, Node *val, Node *ex)
140 : CompareAndSwapNNode(c, mem, adr, val, ex) { }
141
142 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape) {
143 if (in(ExpectedIn) != NULL && phase->type(in(ExpectedIn)) == TypeNarrowOop::NULL_PTR) {
144 return new (phase->C) CompareAndSwapNNode(in(MemNode::Control), in(MemNode::Memory), in(MemNode::Address), in(MemNode::ValueIn), in(ExpectedIn));
145 }
146 return NULL;
147 }
148
149 virtual int Opcode() const;
150 };
151
152 class ShenandoahLoadReferenceBarrierNode : public Node {
153 public:
154 enum {
155 Control,
156 ValueIn
157 };
158
159 enum Strength {
160 NONE, STRONG
161 };
162
163 ShenandoahLoadReferenceBarrierNode(Node* ctrl, Node* val);
164
165 virtual int Opcode() const;
166 virtual const Type* bottom_type() const;
167 virtual const Type* Value(PhaseTransform *phase) const;
168 virtual const class TypePtr *adr_type() const { return TypeOopPtr::BOTTOM; }
169 virtual uint match_edge(uint idx) const {
170 return idx >= ValueIn;
171 }
172 virtual uint ideal_reg() const { return Op_RegP; }
173
174 virtual Node* Identity(PhaseTransform *phase);
175
176 uint size_of() const {
177 return sizeof(*this);
178 }
179
180 Strength get_barrier_strength();
181 CallStaticJavaNode* pin_and_expand_null_check(PhaseIterGVN& igvn);
182
183 private:
184 bool needs_barrier(PhaseTransform* phase, Node* n);
185 bool needs_barrier_impl(PhaseTransform* phase, Node* n, Unique_Node_List &visited);
186 };
187
188
189 #endif // SHARE_GC_SHENANDOAH_C2_SHENANDOAHSUPPORT_HPP