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_VM_GC_SHENANDOAH_C2_SHENANDOAH_SUPPORT_HPP 25 #define SHARE_VM_GC_SHENANDOAH_C2_SHENANDOAH_SUPPORT_HPP 26 27 #include "gc/shenandoah/shenandoahBrooksPointer.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 PhaseGVN; 37 class MemoryGraphFixer; 38 39 class ShenandoahBarrierNode : public TypeNode { 40 private: 41 bool _allow_fromspace; 42 43 #ifdef ASSERT 44 enum verify_type { 45 ShenandoahLoad, 46 ShenandoahStore, 47 ShenandoahValue, 48 ShenandoahOopStore, 49 ShenandoahNone, 50 }; 51 52 static bool verify_helper(Node* in, Node_Stack& phis, VectorSet& visited, verify_type t, bool trace, Unique_Node_List& barriers_used); 53 #endif 54 55 public: 56 enum { Control, 57 Memory, 58 ValueIn 59 }; 60 61 ShenandoahBarrierNode(Node* ctrl, Node* mem, Node* obj, bool allow_fromspace) 62 : TypeNode(obj->bottom_type()->isa_oopptr() ? obj->bottom_type()->is_oopptr()->cast_to_nonconst() : obj->bottom_type(), 3), 63 _allow_fromspace(allow_fromspace) { 64 65 init_req(Control, ctrl); 66 init_req(Memory, mem); 67 init_req(ValueIn, obj); 68 69 init_class_id(Class_ShenandoahBarrier); 70 } 71 72 static Node* skip_through_barrier(Node* n); 73 74 static const TypeOopPtr* brooks_pointer_type(const Type* t) { 75 return t->is_oopptr()->cast_to_nonconst()->add_offset(ShenandoahBrooksPointer::byte_offset())->is_oopptr(); 76 } 77 78 virtual const TypePtr* adr_type() const { 79 if (bottom_type() == Type::TOP) { 80 return NULL; 81 } 82 //const TypePtr* adr_type = in(MemNode::Address)->bottom_type()->is_ptr(); 83 const TypePtr* adr_type = brooks_pointer_type(bottom_type()); 84 assert(adr_type->offset() == ShenandoahBrooksPointer::byte_offset(), "sane offset"); 85 assert(Compile::current()->alias_type(adr_type)->is_rewritable(), "brooks ptr must be rewritable"); 86 return adr_type; 87 } 88 89 virtual uint ideal_reg() const { return Op_RegP; } 90 virtual uint match_edge(uint idx) const { 91 return idx >= ValueIn; 92 } 93 94 Node* Identity_impl(PhaseGVN* phase); 95 96 virtual const Type* Value(PhaseGVN* phase) const; 97 virtual bool depends_only_on_test() const { 98 return true; 99 }; 100 101 static bool needs_barrier(PhaseGVN* phase, ShenandoahBarrierNode* orig, Node* n, Node* rb_mem, bool allow_fromspace); 102 103 #ifdef ASSERT 104 static void report_verify_failure(const char* msg, Node* n1 = NULL, Node* n2 = NULL); 105 static void verify(RootNode* root); 106 static void verify_raw_mem(RootNode* root); 107 #endif 108 #ifndef PRODUCT 109 virtual void dump_spec(outputStream *st) const; 110 #endif 111 112 // protected: 113 static Node* dom_mem(Node* mem, Node*& mem_ctrl, Node* n, Node* rep_ctrl, int alias, PhaseIdealLoop* phase); 114 static Node* dom_mem(Node* mem, Node* ctrl, int alias, Node*& mem_ctrl, PhaseIdealLoop* phase); 115 static bool is_dominator(Node *d_c, Node *n_c, Node* d, Node* n, PhaseIdealLoop* phase); 116 static bool is_dominator_same_ctrl(Node* c, Node* d, Node* n, PhaseIdealLoop* phase); 117 static Node* no_branches(Node* c, Node* dom, bool allow_one_proj, PhaseIdealLoop* phase); 118 static bool build_loop_late_post(PhaseIdealLoop* phase, Node* n); 119 bool sink_node(PhaseIdealLoop* phase, Node* ctrl, Node* n_ctrl); 120 121 protected: 122 uint hash() const; 123 uint cmp(const Node& n) const; 124 uint size_of() const; 125 126 private: 127 static bool needs_barrier_impl(PhaseGVN* phase, ShenandoahBarrierNode* orig, Node* n, Node* rb_mem, bool allow_fromspace, Unique_Node_List &visited); 128 129 static bool dominates_memory(PhaseGVN* phase, Node* b1, Node* b2, bool linear); 130 static bool dominates_memory_impl(PhaseGVN* phase, Node* b1, Node* b2, Node* current, bool linear); 131 }; 132 133 class ShenandoahReadBarrierNode : public ShenandoahBarrierNode { 134 public: 135 ShenandoahReadBarrierNode(Node* ctrl, Node* mem, Node* obj) 136 : ShenandoahBarrierNode(ctrl, mem, obj, true) { 137 assert(UseShenandoahGC && (ShenandoahReadBarrier || ShenandoahStoreValReadBarrier || 138 ShenandoahWriteBarrier || ShenandoahAcmpBarrier), 139 "should be enabled"); 140 } 141 ShenandoahReadBarrierNode(Node* ctrl, Node* mem, Node* obj, bool allow_fromspace) 142 : ShenandoahBarrierNode(ctrl, mem, obj, allow_fromspace) { 143 assert(UseShenandoahGC && (ShenandoahReadBarrier || ShenandoahStoreValReadBarrier || 144 ShenandoahWriteBarrier || ShenandoahAcmpBarrier), 145 "should be enabled"); 146 } 147 148 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape); 149 virtual Node* Identity(PhaseGVN* phase); 150 virtual int Opcode() const; 151 152 bool is_independent(Node* mem); 153 154 void try_move(PhaseIdealLoop* phase); 155 156 private: 157 static bool is_independent(const Type* in_type, const Type* this_type); 158 static bool dominates_memory_rb(PhaseGVN* phase, Node* b1, Node* b2, bool linear); 159 static bool dominates_memory_rb_impl(PhaseGVN* phase, Node* b1, Node* b2, Node* current, bool linear); 160 }; 161 162 class ShenandoahWriteBarrierNode : public ShenandoahBarrierNode { 163 public: 164 ShenandoahWriteBarrierNode(Compile* C, Node* ctrl, Node* mem, Node* obj); 165 166 virtual int Opcode() const; 167 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape); 168 virtual Node* Identity(PhaseGVN* phase); 169 virtual bool depends_only_on_test() const { return false; } 170 171 static bool expand(Compile* C, PhaseIterGVN& igvn); 172 static bool is_gc_state_load(Node *n); 173 static bool is_heap_state_test(Node* iff, int mask); 174 static bool is_heap_stable_test(Node* iff); 175 static bool try_common_gc_state_load(Node *n, PhaseIdealLoop *phase); 176 static bool has_safepoint_between(Node* start, Node* stop, PhaseIdealLoop *phase); 177 178 static LoopNode* try_move_before_pre_loop(Node* c, Node* val_ctrl, PhaseIdealLoop* phase); 179 static Node* move_above_predicates(LoopNode* cl, Node* val_ctrl, PhaseIdealLoop* phase); 180 #ifdef ASSERT 181 static bool memory_dominates_all_paths(Node* mem, Node* rep_ctrl, int alias, PhaseIdealLoop* phase); 182 static void memory_dominates_all_paths_helper(Node* c, Node* rep_ctrl, Unique_Node_List& controls, PhaseIdealLoop* phase); 183 #endif 184 void try_move_before_loop(GrowableArray<MemoryGraphFixer*>& memory_graph_fixers, PhaseIdealLoop* phase, bool include_lsm, Unique_Node_List& uses); 185 void try_move_before_loop_helper(LoopNode* cl, Node* val_ctrl, GrowableArray<MemoryGraphFixer*>& memory_graph_fixers, PhaseIdealLoop* phase, bool include_lsm, Unique_Node_List& uses); 186 static void pin_and_expand(PhaseIdealLoop* phase); 187 CallStaticJavaNode* pin_and_expand_null_check(PhaseIterGVN& igvn); 188 void pin_and_expand_move_barrier(PhaseIdealLoop* phase, GrowableArray<MemoryGraphFixer*>& memory_graph_fixers, Unique_Node_List& uses); 189 void pin_and_expand_helper(PhaseIdealLoop* phase); 190 static Node* find_bottom_mem(Node* ctrl, PhaseIdealLoop* phase); 191 static void follow_barrier_uses(Node* n, Node* ctrl, Unique_Node_List& uses, PhaseIdealLoop* phase); 192 static void test_null(Node*& ctrl, Node* val, Node*& null_ctrl, PhaseIdealLoop* phase); 193 194 static void test_heap_stable(Node*& ctrl, Node* raw_mem, Node*& heap_stable_ctrl, 195 PhaseIdealLoop* phase); 196 static void call_wb_stub(Node*& ctrl, Node*& val, Node*& result_mem, 197 Node* raw_mem, Node* wb_mem, int alias, 198 PhaseIdealLoop* phase); 199 static Node* clone_null_check(Node*& c, Node* val, Node* unc_ctrl, PhaseIdealLoop* phase); 200 static void fix_null_check(Node* unc, Node* unc_ctrl, Node* new_unc_ctrl, Unique_Node_List& uses, 201 PhaseIdealLoop* phase); 202 static void in_cset_fast_test(Node*& ctrl, Node*& not_cset_ctrl, Node* val, Node* raw_mem, PhaseIdealLoop* phase); 203 static void move_heap_stable_test_out_of_loop(IfNode* iff, PhaseIdealLoop* phase); 204 205 static void optimize_after_expansion(VectorSet &visited, Node_Stack &nstack, Node_List &old_new, PhaseIdealLoop* phase); 206 static void merge_back_to_back_tests(Node* n, PhaseIdealLoop* phase); 207 static bool identical_backtoback_ifs(Node *n, PhaseIdealLoop* phase); 208 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); 209 210 static void optimize_before_expansion(PhaseIdealLoop* phase, GrowableArray<MemoryGraphFixer*> memory_graph_fixers, bool include_lsm); 211 Node* would_subsume(ShenandoahBarrierNode* other, PhaseIdealLoop* phase); 212 static IfNode* find_unswitching_candidate(const IdealLoopTree *loop, PhaseIdealLoop* phase); 213 214 Node* try_split_thru_phi(PhaseIdealLoop* phase); 215 }; 216 217 class ShenandoahWBMemProjNode : public Node { 218 public: 219 enum { Control, 220 WriteBarrier }; 221 222 ShenandoahWBMemProjNode(Node *src) : Node(NULL, src) { 223 assert(UseShenandoahGC && ShenandoahWriteBarrier, "should be enabled"); 224 assert(src->Opcode() == Op_ShenandoahWriteBarrier || src->is_Mach(), "epxect wb"); 225 } 226 virtual Node* Identity(PhaseGVN* phase); 227 228 virtual int Opcode() const; 229 virtual bool is_CFG() const { return false; } 230 virtual const Type *bottom_type() const {return Type::MEMORY;} 231 virtual const TypePtr *adr_type() const { 232 Node* wb = in(WriteBarrier); 233 if (wb == NULL || wb->is_top()) return NULL; // node is dead 234 assert(wb->Opcode() == Op_ShenandoahWriteBarrier || (wb->is_Mach() && wb->as_Mach()->ideal_Opcode() == Op_ShenandoahWriteBarrier) || wb->is_Phi(), "expect wb"); 235 return ShenandoahBarrierNode::brooks_pointer_type(wb->bottom_type()); 236 } 237 238 virtual uint ideal_reg() const { return 0;} // memory projections don't have a register 239 virtual const Type *Value(PhaseGVN* phase ) const { 240 return bottom_type(); 241 } 242 #ifndef PRODUCT 243 virtual void dump_spec(outputStream *st) const {}; 244 #endif 245 }; 246 247 class ShenandoahEnqueueBarrierNode : public Node { 248 public: 249 ShenandoahEnqueueBarrierNode(Node* val) : Node(NULL, val) { 250 } 251 252 const Type *bottom_type() const; 253 const Type* Value(PhaseGVN* phase) const; 254 Node* Identity(PhaseGVN* phase); 255 256 int Opcode() const; 257 258 private: 259 enum { Needed, NotNeeded, MaybeNeeded }; 260 261 static int needed(Node* n); 262 static Node* next(Node* n); 263 }; 264 265 class MemoryGraphFixer : public ResourceObj { 266 private: 267 Node_List _memory_nodes; 268 int _alias; 269 PhaseIdealLoop* _phase; 270 bool _include_lsm; 271 272 void collect_memory_nodes(); 273 Node* get_ctrl(Node* n) const; 274 Node* ctrl_or_self(Node* n) const; 275 bool mem_is_valid(Node* m, Node* c) const; 276 MergeMemNode* allocate_merge_mem(Node* mem, Node* rep_proj, Node* rep_ctrl) const; 277 MergeMemNode* clone_merge_mem(Node* u, Node* mem, Node* rep_proj, Node* rep_ctrl, DUIterator& i) const; 278 void fix_memory_uses(Node* mem, Node* replacement, Node* rep_proj, Node* rep_ctrl) const; 279 bool should_process_phi(Node* phi) const; 280 bool has_mem_phi(Node* region) const; 281 282 public: 283 MemoryGraphFixer(int alias, bool include_lsm, PhaseIdealLoop* phase) : 284 _alias(alias), _phase(phase), _include_lsm(include_lsm) { 285 assert(_alias != Compile::AliasIdxBot, "unsupported"); 286 collect_memory_nodes(); 287 } 288 289 Node* find_mem(Node* ctrl, Node* n) const; 290 void fix_mem(Node* ctrl, Node* region, Node* mem, Node* mem_for_ctrl, Node* mem_phi, Unique_Node_List& uses); 291 int alias() const { return _alias; } 292 void remove(Node* n); 293 }; 294 295 class ShenandoahCompareAndSwapPNode : public CompareAndSwapPNode { 296 public: 297 ShenandoahCompareAndSwapPNode(Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) 298 : CompareAndSwapPNode(c, mem, adr, val, ex, mem_ord) { } 299 300 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape) { 301 if (in(ExpectedIn) != NULL && phase->type(in(ExpectedIn)) == TypePtr::NULL_PTR) { 302 return new CompareAndSwapPNode(in(MemNode::Control), in(MemNode::Memory), in(MemNode::Address), in(MemNode::ValueIn), in(ExpectedIn), order()); 303 } 304 return NULL; 305 } 306 307 virtual int Opcode() const; 308 }; 309 310 class ShenandoahCompareAndSwapNNode : public CompareAndSwapNNode { 311 public: 312 ShenandoahCompareAndSwapNNode(Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) 313 : CompareAndSwapNNode(c, mem, adr, val, ex, mem_ord) { } 314 315 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape) { 316 if (in(ExpectedIn) != NULL && phase->type(in(ExpectedIn)) == TypeNarrowOop::NULL_PTR) { 317 return new CompareAndSwapNNode(in(MemNode::Control), in(MemNode::Memory), in(MemNode::Address), in(MemNode::ValueIn), in(ExpectedIn), order()); 318 } 319 return NULL; 320 } 321 322 virtual int Opcode() const; 323 }; 324 325 class ShenandoahWeakCompareAndSwapPNode : public WeakCompareAndSwapPNode { 326 public: 327 ShenandoahWeakCompareAndSwapPNode(Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) 328 : WeakCompareAndSwapPNode(c, mem, adr, val, ex, mem_ord) { } 329 330 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape) { 331 if (in(ExpectedIn) != NULL && phase->type(in(ExpectedIn)) == TypePtr::NULL_PTR) { 332 return new WeakCompareAndSwapPNode(in(MemNode::Control), in(MemNode::Memory), in(MemNode::Address), in(MemNode::ValueIn), in(ExpectedIn), order()); 333 } 334 return NULL; 335 } 336 337 virtual int Opcode() const; 338 }; 339 340 class ShenandoahWeakCompareAndSwapNNode : public WeakCompareAndSwapNNode { 341 public: 342 ShenandoahWeakCompareAndSwapNNode(Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) 343 : WeakCompareAndSwapNNode(c, mem, adr, val, ex, mem_ord) { } 344 345 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape) { 346 if (in(ExpectedIn) != NULL && phase->type(in(ExpectedIn)) == TypeNarrowOop::NULL_PTR) { 347 return new WeakCompareAndSwapNNode(in(MemNode::Control), in(MemNode::Memory), in(MemNode::Address), in(MemNode::ValueIn), in(ExpectedIn), order()); 348 } 349 return NULL; 350 } 351 352 virtual int Opcode() const; 353 }; 354 355 class ShenandoahCompareAndExchangePNode : public CompareAndExchangePNode { 356 public: 357 ShenandoahCompareAndExchangePNode(Node *c, Node *mem, Node *adr, Node *val, Node *ex, const TypePtr* at, const Type* t, MemNode::MemOrd mem_ord) 358 : CompareAndExchangePNode(c, mem, adr, val, ex, at, t, mem_ord) { } 359 360 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape) { 361 if (in(ExpectedIn) != NULL && phase->type(in(ExpectedIn)) == TypePtr::NULL_PTR) { 362 return new CompareAndExchangePNode(in(MemNode::Control), in(MemNode::Memory), in(MemNode::Address), in(MemNode::ValueIn), in(ExpectedIn), adr_type(), bottom_type(), order()); 363 } 364 return NULL; 365 } 366 367 virtual int Opcode() const; 368 }; 369 370 class ShenandoahCompareAndExchangeNNode : public CompareAndExchangeNNode { 371 public: 372 ShenandoahCompareAndExchangeNNode(Node *c, Node *mem, Node *adr, Node *val, Node *ex, const TypePtr* at, const Type* t, MemNode::MemOrd mem_ord) 373 : CompareAndExchangeNNode(c, mem, adr, val, ex, at, t, mem_ord) { } 374 375 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape) { 376 if (in(ExpectedIn) != NULL && phase->type(in(ExpectedIn)) == TypeNarrowOop::NULL_PTR) { 377 return new CompareAndExchangeNNode(in(MemNode::Control), in(MemNode::Memory), in(MemNode::Address), in(MemNode::ValueIn), in(ExpectedIn), adr_type(), bottom_type(), order()); 378 } 379 return NULL; 380 } 381 382 virtual int Opcode() const; 383 }; 384 385 #endif // SHARE_VM_GC_SHENANDOAH_C2_SHENANDOAH_SUPPORT_HPP