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 move_gc_state_test_out_of_loop(IfNode* iff, PhaseIdealLoop* phase); 71 static void merge_back_to_back_tests(Node* n, PhaseIdealLoop* phase); 72 static bool merge_point_safe(Node* region); 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& nodes_above_barrier, uint last, PhaseIdealLoop* phase); 75 static IfNode* find_unswitching_candidate(const IdealLoopTree *loop, PhaseIdealLoop* phase); 76 77 static Node* get_load_addr(PhaseIdealLoop* phase, VectorSet& visited, Node* lrb); 78 public: 79 static bool is_dominator(Node* d_c, Node* n_c, Node* d, Node* n, PhaseIdealLoop* phase); 80 static bool is_dominator_same_ctrl(Node* c, Node* d, Node* n, PhaseIdealLoop* phase); 81 82 static bool is_gc_state_load(Node* n); 83 static bool is_heap_stable_test(Node* iff); 84 85 static bool expand(Compile* C, PhaseIterGVN& igvn); 86 static void pin_and_expand(PhaseIdealLoop* phase); 87 static void optimize_after_expansion(VectorSet& visited, Node_Stack& nstack, Node_List& old_new, PhaseIdealLoop* phase); 88 89 static void push_data_inputs_at_control(PhaseIdealLoop* phase, Node* n, Node* ctrl, 90 Unique_Node_List &wq); 91 static bool is_anti_dependent_load_at_control(PhaseIdealLoop* phase, Node* maybe_load, Node* store, Node* control); 92 93 static void maybe_push_anti_dependent_loads(PhaseIdealLoop* phase, Node* maybe_store, Node* control, Unique_Node_List &wq); 94 #ifdef ASSERT 95 static void verify(RootNode* root); 96 #endif 97 }; 98 99 class ShenandoahIUBarrierNode : public Node { 100 public: 101 ShenandoahIUBarrierNode(Node* val); 102 103 const Type *bottom_type() const; 104 const Type* Value(PhaseGVN* phase) const; 105 Node* Identity(PhaseGVN* phase); 106 107 int Opcode() const; 108 109 private: 110 enum { Needed, NotNeeded, MaybeNeeded }; 111 112 static int needed(Node* n); 113 static Node* next(Node* n); 114 }; 115 116 class MemoryGraphFixer : public ResourceObj { 117 private: 118 Node_List _memory_nodes; 119 int _alias; 120 PhaseIdealLoop* _phase; 121 bool _include_lsm; 122 123 void collect_memory_nodes(); 124 Node* get_ctrl(Node* n) const; 125 Node* ctrl_or_self(Node* n) const; 126 bool mem_is_valid(Node* m, Node* c) const; 127 MergeMemNode* allocate_merge_mem(Node* mem, Node* rep_proj, Node* rep_ctrl) const; 128 MergeMemNode* clone_merge_mem(Node* u, Node* mem, Node* rep_proj, Node* rep_ctrl, DUIterator& i) const; 129 void fix_memory_uses(Node* mem, Node* replacement, Node* rep_proj, Node* rep_ctrl) const; 130 bool should_process_phi(Node* phi) const; 131 bool has_mem_phi(Node* region) const; 132 133 public: 134 MemoryGraphFixer(int alias, bool include_lsm, PhaseIdealLoop* phase) : 135 _alias(alias), _phase(phase), _include_lsm(include_lsm) { 136 assert(_alias != Compile::AliasIdxBot, "unsupported"); 137 collect_memory_nodes(); 138 } 139 140 Node* find_mem(Node* ctrl, Node* n) const; 141 void fix_mem(Node* ctrl, Node* region, Node* mem, Node* mem_for_ctrl, Node* mem_phi, Unique_Node_List& uses); 142 int alias() const { return _alias; } 143 144 Node* collect_memory_for_infinite_loop(const Node* in); 145 146 void record_new_ctrl(Node* ctrl, Node* region, Node* mem, Node* mem_for_ctrl); 147 }; 148 149 class ShenandoahCompareAndSwapPNode : public CompareAndSwapPNode { 150 public: 151 ShenandoahCompareAndSwapPNode(Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) 152 : CompareAndSwapPNode(c, mem, adr, val, ex, mem_ord) { } 153 154 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape) { 155 if (in(ExpectedIn) != nullptr && phase->type(in(ExpectedIn)) == TypePtr::NULL_PTR) { 156 return new CompareAndSwapPNode(in(MemNode::Control), in(MemNode::Memory), in(MemNode::Address), in(MemNode::ValueIn), in(ExpectedIn), order()); 157 } 158 return nullptr; 159 } 160 161 virtual int Opcode() const; 162 }; 163 164 class ShenandoahCompareAndSwapNNode : public CompareAndSwapNNode { 165 public: 166 ShenandoahCompareAndSwapNNode(Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) 167 : CompareAndSwapNNode(c, mem, adr, val, ex, mem_ord) { } 168 169 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape) { 170 if (in(ExpectedIn) != nullptr && phase->type(in(ExpectedIn)) == TypeNarrowOop::NULL_PTR) { 171 return new CompareAndSwapNNode(in(MemNode::Control), in(MemNode::Memory), in(MemNode::Address), in(MemNode::ValueIn), in(ExpectedIn), order()); 172 } 173 return nullptr; 174 } 175 176 virtual int Opcode() const; 177 }; 178 179 class ShenandoahWeakCompareAndSwapPNode : public WeakCompareAndSwapPNode { 180 public: 181 ShenandoahWeakCompareAndSwapPNode(Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) 182 : WeakCompareAndSwapPNode(c, mem, adr, val, ex, mem_ord) { } 183 184 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape) { 185 if (in(ExpectedIn) != nullptr && phase->type(in(ExpectedIn)) == TypePtr::NULL_PTR) { 186 return new WeakCompareAndSwapPNode(in(MemNode::Control), in(MemNode::Memory), in(MemNode::Address), in(MemNode::ValueIn), in(ExpectedIn), order()); 187 } 188 return nullptr; 189 } 190 191 virtual int Opcode() const; 192 }; 193 194 class ShenandoahWeakCompareAndSwapNNode : public WeakCompareAndSwapNNode { 195 public: 196 ShenandoahWeakCompareAndSwapNNode(Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) 197 : WeakCompareAndSwapNNode(c, mem, adr, val, ex, mem_ord) { } 198 199 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape) { 200 if (in(ExpectedIn) != nullptr && phase->type(in(ExpectedIn)) == TypeNarrowOop::NULL_PTR) { 201 return new WeakCompareAndSwapNNode(in(MemNode::Control), in(MemNode::Memory), in(MemNode::Address), in(MemNode::ValueIn), in(ExpectedIn), order()); 202 } 203 return nullptr; 204 } 205 206 virtual int Opcode() const; 207 }; 208 209 class ShenandoahCompareAndExchangePNode : public CompareAndExchangePNode { 210 public: 211 ShenandoahCompareAndExchangePNode(Node *c, Node *mem, Node *adr, Node *val, Node *ex, const TypePtr* at, const Type* t, MemNode::MemOrd mem_ord) 212 : CompareAndExchangePNode(c, mem, adr, val, ex, at, t, mem_ord) { } 213 214 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape) { 215 if (in(ExpectedIn) != nullptr && phase->type(in(ExpectedIn)) == TypePtr::NULL_PTR) { 216 return new CompareAndExchangePNode(in(MemNode::Control), in(MemNode::Memory), in(MemNode::Address), in(MemNode::ValueIn), in(ExpectedIn), adr_type(), bottom_type(), order()); 217 } 218 return nullptr; 219 } 220 221 virtual int Opcode() const; 222 }; 223 224 class ShenandoahCompareAndExchangeNNode : public CompareAndExchangeNNode { 225 public: 226 ShenandoahCompareAndExchangeNNode(Node *c, Node *mem, Node *adr, Node *val, Node *ex, const TypePtr* at, const Type* t, MemNode::MemOrd mem_ord) 227 : CompareAndExchangeNNode(c, mem, adr, val, ex, at, t, mem_ord) { } 228 229 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape) { 230 if (in(ExpectedIn) != nullptr && phase->type(in(ExpectedIn)) == TypeNarrowOop::NULL_PTR) { 231 return new CompareAndExchangeNNode(in(MemNode::Control), in(MemNode::Memory), in(MemNode::Address), in(MemNode::ValueIn), in(ExpectedIn), adr_type(), bottom_type(), order()); 232 } 233 return nullptr; 234 } 235 236 virtual int Opcode() const; 237 }; 238 239 class ShenandoahLoadReferenceBarrierNode : public Node { 240 public: 241 enum { 242 Control, 243 ValueIn 244 }; 245 246 private: 247 DecoratorSet _decorators; 248 249 public: 250 ShenandoahLoadReferenceBarrierNode(Node* ctrl, Node* val, DecoratorSet decorators); 251 252 DecoratorSet decorators() const; 253 virtual int Opcode() const; 254 virtual const Type* bottom_type() const; 255 virtual const Type* Value(PhaseGVN* phase) const; 256 virtual const class TypePtr *adr_type() const { return TypeOopPtr::BOTTOM; } 257 virtual uint match_edge(uint idx) const { 258 return idx >= ValueIn; 259 } 260 virtual uint ideal_reg() const { return Op_RegP; } 261 262 virtual Node* Identity(PhaseGVN* phase); 263 264 virtual uint size_of() const; 265 virtual uint hash() const; 266 virtual bool cmp( const Node &n ) const; 267 268 private: 269 bool needs_barrier(PhaseGVN* phase, Node* n); 270 bool needs_barrier_impl(PhaseGVN* phase, Node* n, Unique_Node_List &visited); 271 }; 272 273 274 #endif // SHARE_GC_SHENANDOAH_C2_SHENANDOAHSUPPORT_HPP