1 /*
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4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5 *
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12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
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25
26 #ifndef SHARE_OPTO_MEMNODE_HPP
27 #define SHARE_OPTO_MEMNODE_HPP
28
29 #include "opto/multnode.hpp"
30 #include "opto/node.hpp"
31 #include "opto/opcodes.hpp"
32 #include "opto/type.hpp"
33
34 // Portions of code courtesy of Clifford Click
35
36 class MultiNode;
37 class PhaseCCP;
38 class PhaseTransform;
39
40 //------------------------------MemNode----------------------------------------
41 // Load or Store, possibly throwing a null pointer exception
42 class MemNode : public Node {
43 private:
44 bool _unaligned_access; // Unaligned access from unsafe
45 bool _mismatched_access; // Mismatched access from unsafe: byte read in integer array for instance
46 bool _unsafe_access; // Access of unsafe origin.
47 uint8_t _barrier_data; // Bit field with barrier information
48
49 protected:
50 #ifdef ASSERT
51 const TypePtr* _adr_type; // What kind of memory is being addressed?
52 #endif
53 virtual uint size_of() const;
54 public:
55 enum { Control, // When is it safe to do this load?
56 Memory, // Chunk of memory is being loaded from
57 Address, // Actually address, derived from base
58 ValueIn // Value to store
59 };
60 typedef enum { unordered = 0,
61 acquire, // Load has to acquire or be succeeded by MemBarAcquire.
62 release, // Store has to release or be preceded by MemBarRelease.
63 seqcst, // LoadStore has to have both acquire and release semantics.
64 unset // The memory ordering is not set (used for testing)
65 } MemOrd;
66 protected:
67 MemNode( Node *c0, Node *c1, Node *c2, const TypePtr* at ) :
68 Node(c0,c1,c2),
69 _unaligned_access(false),
70 _mismatched_access(false),
71 _unsafe_access(false),
72 _barrier_data(0) {
73 init_class_id(Class_Mem);
74 debug_only(_adr_type=at; adr_type();)
75 }
76 MemNode( Node *c0, Node *c1, Node *c2, const TypePtr* at, Node *c3 ) :
77 Node(c0,c1,c2,c3),
78 _unaligned_access(false),
79 _mismatched_access(false),
80 _unsafe_access(false),
81 _barrier_data(0) {
82 init_class_id(Class_Mem);
83 debug_only(_adr_type=at; adr_type();)
84 }
85 MemNode( Node *c0, Node *c1, Node *c2, const TypePtr* at, Node *c3, Node *c4) :
86 Node(c0,c1,c2,c3,c4),
87 _unaligned_access(false),
88 _mismatched_access(false),
89 _unsafe_access(false),
90 _barrier_data(0) {
91 init_class_id(Class_Mem);
92 debug_only(_adr_type=at; adr_type();)
93 }
94
95 virtual Node* find_previous_arraycopy(PhaseValues* phase, Node* ld_alloc, Node*& mem, bool can_see_stored_value) const { return nullptr; }
96 ArrayCopyNode* find_array_copy_clone(Node* ld_alloc, Node* mem) const;
97 static bool check_if_adr_maybe_raw(Node* adr);
98
99 public:
100 // Helpers for the optimizer. Documented in memnode.cpp.
101 static bool detect_ptr_independence(Node* p1, AllocateNode* a1,
102 Node* p2, AllocateNode* a2,
103 PhaseTransform* phase);
104 static bool adr_phi_is_loop_invariant(Node* adr_phi, Node* cast);
105
106 static Node *optimize_simple_memory_chain(Node *mchain, const TypeOopPtr *t_oop, Node *load, PhaseGVN *phase);
107 static Node *optimize_memory_chain(Node *mchain, const TypePtr *t_adr, Node *load, PhaseGVN *phase);
108 // The following two should probably be phase-specific functions:
109 static DomResult maybe_all_controls_dominate(Node* dom, Node* sub);
110 static bool all_controls_dominate(Node* dom, Node* sub) {
111 DomResult dom_result = maybe_all_controls_dominate(dom, sub);
112 return dom_result == DomResult::Dominate;
113 }
114
115 virtual const class TypePtr *adr_type() const; // returns bottom_type of address
116
117 // Shared code for Ideal methods:
118 Node *Ideal_common(PhaseGVN *phase, bool can_reshape); // Return -1 for short-circuit null.
119
120 // Helper function for adr_type() implementations.
121 static const TypePtr* calculate_adr_type(const Type* t, const TypePtr* cross_check = nullptr);
122
123 // Raw access function, to allow copying of adr_type efficiently in
124 // product builds and retain the debug info for debug builds.
125 const TypePtr *raw_adr_type() const {
126 return DEBUG_ONLY(_adr_type) NOT_DEBUG(nullptr);
127 }
128
129 // Return the barrier data of n, if available, or 0 otherwise.
130 static uint8_t barrier_data(const Node* n);
131
132 // Map a load or store opcode to its corresponding store opcode.
133 // (Return -1 if unknown.)
134 virtual int store_Opcode() const { return -1; }
135
136 // What is the type of the value in memory? (T_VOID mean "unspecified".)
137 virtual BasicType memory_type() const = 0;
138 virtual int memory_size() const {
139 #ifdef ASSERT
140 return type2aelembytes(memory_type(), true);
141 #else
142 return type2aelembytes(memory_type());
143 #endif
144 }
145
146 uint8_t barrier_data() { return _barrier_data; }
147 void set_barrier_data(uint8_t barrier_data) { _barrier_data = barrier_data; }
148
149 // Search through memory states which precede this node (load or store).
150 // Look for an exact match for the address, with no intervening
151 // aliased stores.
152 Node* find_previous_store(PhaseValues* phase);
153
154 // Can this node (load or store) accurately see a stored value in
155 // the given memory state? (The state may or may not be in(Memory).)
156 Node* can_see_stored_value(Node* st, PhaseValues* phase) const;
157
158 void set_unaligned_access() { _unaligned_access = true; }
159 bool is_unaligned_access() const { return _unaligned_access; }
160 void set_mismatched_access() { _mismatched_access = true; }
161 bool is_mismatched_access() const { return _mismatched_access; }
162 void set_unsafe_access() { _unsafe_access = true; }
163 bool is_unsafe_access() const { return _unsafe_access; }
164
165 #ifndef PRODUCT
166 static void dump_adr_type(const Node* mem, const TypePtr* adr_type, outputStream *st);
167 virtual void dump_spec(outputStream *st) const;
168 #endif
169 };
170
171 //------------------------------LoadNode---------------------------------------
172 // Load value; requires Memory and Address
173 class LoadNode : public MemNode {
174 public:
175 // Some loads (from unsafe) should be pinned: they don't depend only
176 // on the dominating test. The field _control_dependency below records
177 // whether that node depends only on the dominating test.
178 // Pinned and UnknownControl are similar, but differ in that Pinned
179 // loads are not allowed to float across safepoints, whereas UnknownControl
180 // loads are allowed to do that. Therefore, Pinned is stricter.
181 enum ControlDependency {
182 Pinned,
183 UnknownControl,
184 DependsOnlyOnTest
185 };
186
187 private:
188 // LoadNode::hash() doesn't take the _control_dependency field
189 // into account: If the graph already has a non-pinned LoadNode and
190 // we add a pinned LoadNode with the same inputs, it's safe for GVN
191 // to replace the pinned LoadNode with the non-pinned LoadNode,
192 // otherwise it wouldn't be safe to have a non pinned LoadNode with
193 // those inputs in the first place. If the graph already has a
194 // pinned LoadNode and we add a non pinned LoadNode with the same
195 // inputs, it's safe (but suboptimal) for GVN to replace the
196 // non-pinned LoadNode by the pinned LoadNode.
197 ControlDependency _control_dependency;
198
199 // On platforms with weak memory ordering (e.g., PPC) we distinguish
200 // loads that can be reordered, and such requiring acquire semantics to
201 // adhere to the Java specification. The required behaviour is stored in
202 // this field.
203 const MemOrd _mo;
204
205 AllocateNode* is_new_object_mark_load() const;
206
207 protected:
208 virtual bool cmp(const Node &n) const;
209 virtual uint size_of() const; // Size is bigger
210 // Should LoadNode::Ideal() attempt to remove control edges?
211 virtual bool can_remove_control() const;
212 const Type* const _type; // What kind of value is loaded?
213
214 virtual Node* find_previous_arraycopy(PhaseValues* phase, Node* ld_alloc, Node*& mem, bool can_see_stored_value) const;
215 public:
216
217 LoadNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const Type *rt, MemOrd mo, ControlDependency control_dependency)
218 : MemNode(c,mem,adr,at), _control_dependency(control_dependency), _mo(mo), _type(rt) {
219 init_class_id(Class_Load);
220 }
221 inline bool is_unordered() const { return !is_acquire(); }
222 inline bool is_acquire() const {
223 assert(_mo == unordered || _mo == acquire, "unexpected");
224 return _mo == acquire;
225 }
226 inline bool is_unsigned() const {
227 int lop = Opcode();
228 return (lop == Op_LoadUB) || (lop == Op_LoadUS);
229 }
230
231 // Polymorphic factory method:
232 static Node* make(PhaseGVN& gvn, Node* c, Node* mem, Node* adr,
233 const TypePtr* at, const Type* rt, BasicType bt,
234 MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest,
235 bool require_atomic_access = false, bool unaligned = false, bool mismatched = false, bool unsafe = false,
236 uint8_t barrier_data = 0);
237
238 virtual uint hash() const; // Check the type
239
240 // Handle algebraic identities here. If we have an identity, return the Node
241 // we are equivalent to. We look for Load of a Store.
242 virtual Node* Identity(PhaseGVN* phase);
243
244 // If the load is from Field memory and the pointer is non-null, it might be possible to
245 // zero out the control input.
246 // If the offset is constant and the base is an object allocation,
247 // try to hook me up to the exact initializing store.
248 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
249
250 // Return true if it's possible to split the Load through a Phi merging the bases
251 bool can_split_through_phi_base(PhaseGVN *phase);
252
253 // Split instance field load through Phi.
254 Node* split_through_phi(PhaseGVN *phase, bool ignore_missing_instance_id = false);
255
256 // Recover original value from boxed values
257 Node *eliminate_autobox(PhaseIterGVN *igvn);
258
259 // Compute a new Type for this node. Basically we just do the pre-check,
260 // then call the virtual add() to set the type.
261 virtual const Type* Value(PhaseGVN* phase) const;
262
263 // Common methods for LoadKlass and LoadNKlass nodes.
264 const Type* klass_value_common(PhaseGVN* phase) const;
265 Node* klass_identity_common(PhaseGVN* phase);
266
267 virtual uint ideal_reg() const;
268 virtual const Type *bottom_type() const;
269 // Following method is copied from TypeNode:
270 void set_type(const Type* t) {
271 assert(t != nullptr, "sanity");
272 debug_only(uint check_hash = (VerifyHashTableKeys && _hash_lock) ? hash() : NO_HASH);
273 *(const Type**)&_type = t; // cast away const-ness
274 // If this node is in the hash table, make sure it doesn't need a rehash.
275 assert(check_hash == NO_HASH || check_hash == hash(), "type change must preserve hash code");
276 }
277 const Type* type() const { assert(_type != nullptr, "sanity"); return _type; };
278
279 // Do not match memory edge
280 virtual uint match_edge(uint idx) const;
281
282 // Map a load opcode to its corresponding store opcode.
283 virtual int store_Opcode() const = 0;
284
285 // Check if the load's memory input is a Phi node with the same control.
286 bool is_instance_field_load_with_local_phi(Node* ctrl);
287
288 Node* convert_to_unsigned_load(PhaseGVN& gvn);
289 Node* convert_to_signed_load(PhaseGVN& gvn);
290
291 bool has_reinterpret_variant(const Type* rt);
292 Node* convert_to_reinterpret_load(PhaseGVN& gvn, const Type* rt);
293
294 ControlDependency control_dependency() const { return _control_dependency; }
295 bool has_unknown_control_dependency() const { return _control_dependency == UnknownControl; }
296 bool has_pinned_control_dependency() const { return _control_dependency == Pinned; }
297
298 LoadNode* pin_array_access_node() const;
299
300 #ifndef PRODUCT
301 virtual void dump_spec(outputStream *st) const;
302 #endif
303 #ifdef ASSERT
304 // Helper function to allow a raw load without control edge for some cases
305 static bool is_immutable_value(Node* adr);
306 #endif
307 protected:
308 const Type* load_array_final_field(const TypeKlassPtr *tkls,
309 ciKlass* klass) const;
310
311 Node* can_see_arraycopy_value(Node* st, PhaseGVN* phase) const;
312
313 // depends_only_on_test is almost always true, and needs to be almost always
314 // true to enable key hoisting & commoning optimizations. However, for the
315 // special case of RawPtr loads from TLS top & end, and other loads performed by
316 // GC barriers, the control edge carries the dependence preventing hoisting past
317 // a Safepoint instead of the memory edge. (An unfortunate consequence of having
318 // Safepoints not set Raw Memory; itself an unfortunate consequence of having Nodes
319 // which produce results (new raw memory state) inside of loops preventing all
320 // manner of other optimizations). Basically, it's ugly but so is the alternative.
321 // See comment in macro.cpp, around line 125 expand_allocate_common().
322 virtual bool depends_only_on_test() const {
323 return adr_type() != TypeRawPtr::BOTTOM && _control_dependency == DependsOnlyOnTest;
324 }
325
326 LoadNode* clone_pinned() const;
327 };
328
329 //------------------------------LoadBNode--------------------------------------
330 // Load a byte (8bits signed) from memory
331 class LoadBNode : public LoadNode {
332 public:
333 LoadBNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeInt *ti, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
334 : LoadNode(c, mem, adr, at, ti, mo, control_dependency) {}
335 virtual int Opcode() const;
336 virtual uint ideal_reg() const { return Op_RegI; }
337 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
338 virtual const Type* Value(PhaseGVN* phase) const;
339 virtual int store_Opcode() const { return Op_StoreB; }
340 virtual BasicType memory_type() const { return T_BYTE; }
341 };
342
343 //------------------------------LoadUBNode-------------------------------------
344 // Load a unsigned byte (8bits unsigned) from memory
345 class LoadUBNode : public LoadNode {
346 public:
347 LoadUBNode(Node* c, Node* mem, Node* adr, const TypePtr* at, const TypeInt* ti, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
348 : LoadNode(c, mem, adr, at, ti, mo, control_dependency) {}
349 virtual int Opcode() const;
350 virtual uint ideal_reg() const { return Op_RegI; }
351 virtual Node* Ideal(PhaseGVN *phase, bool can_reshape);
352 virtual const Type* Value(PhaseGVN* phase) const;
353 virtual int store_Opcode() const { return Op_StoreB; }
354 virtual BasicType memory_type() const { return T_BYTE; }
355 };
356
357 //------------------------------LoadUSNode-------------------------------------
358 // Load an unsigned short/char (16bits unsigned) from memory
359 class LoadUSNode : public LoadNode {
360 public:
361 LoadUSNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeInt *ti, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
362 : LoadNode(c, mem, adr, at, ti, mo, control_dependency) {}
363 virtual int Opcode() const;
364 virtual uint ideal_reg() const { return Op_RegI; }
365 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
366 virtual const Type* Value(PhaseGVN* phase) const;
367 virtual int store_Opcode() const { return Op_StoreC; }
368 virtual BasicType memory_type() const { return T_CHAR; }
369 };
370
371 //------------------------------LoadSNode--------------------------------------
372 // Load a short (16bits signed) from memory
373 class LoadSNode : public LoadNode {
374 public:
375 LoadSNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeInt *ti, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
376 : LoadNode(c, mem, adr, at, ti, mo, control_dependency) {}
377 virtual int Opcode() const;
378 virtual uint ideal_reg() const { return Op_RegI; }
379 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
380 virtual const Type* Value(PhaseGVN* phase) const;
381 virtual int store_Opcode() const { return Op_StoreC; }
382 virtual BasicType memory_type() const { return T_SHORT; }
383 };
384
385 //------------------------------LoadINode--------------------------------------
386 // Load an integer from memory
387 class LoadINode : public LoadNode {
388 public:
389 LoadINode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeInt *ti, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
390 : LoadNode(c, mem, adr, at, ti, mo, control_dependency) {}
391 virtual int Opcode() const;
392 virtual uint ideal_reg() const { return Op_RegI; }
393 virtual int store_Opcode() const { return Op_StoreI; }
394 virtual BasicType memory_type() const { return T_INT; }
395 };
396
397 //------------------------------LoadRangeNode----------------------------------
398 // Load an array length from the array
399 class LoadRangeNode : public LoadINode {
400 public:
401 LoadRangeNode(Node *c, Node *mem, Node *adr, const TypeInt *ti = TypeInt::POS)
402 : LoadINode(c, mem, adr, TypeAryPtr::RANGE, ti, MemNode::unordered) {}
403 virtual int Opcode() const;
404 virtual const Type* Value(PhaseGVN* phase) const;
405 virtual Node* Identity(PhaseGVN* phase);
406 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
407 };
408
409 //------------------------------LoadLNode--------------------------------------
410 // Load a long from memory
411 class LoadLNode : public LoadNode {
412 virtual uint hash() const { return LoadNode::hash() + _require_atomic_access; }
413 virtual bool cmp( const Node &n ) const {
414 return _require_atomic_access == ((LoadLNode&)n)._require_atomic_access
415 && LoadNode::cmp(n);
416 }
417 virtual uint size_of() const { return sizeof(*this); }
418 const bool _require_atomic_access; // is piecewise load forbidden?
419
420 public:
421 LoadLNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeLong *tl,
422 MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest, bool require_atomic_access = false)
423 : LoadNode(c, mem, adr, at, tl, mo, control_dependency), _require_atomic_access(require_atomic_access) {}
424 virtual int Opcode() const;
425 virtual uint ideal_reg() const { return Op_RegL; }
426 virtual int store_Opcode() const { return Op_StoreL; }
427 virtual BasicType memory_type() const { return T_LONG; }
428 bool require_atomic_access() const { return _require_atomic_access; }
429
430 #ifndef PRODUCT
431 virtual void dump_spec(outputStream *st) const {
432 LoadNode::dump_spec(st);
433 if (_require_atomic_access) st->print(" Atomic!");
434 }
435 #endif
436 };
437
438 //------------------------------LoadL_unalignedNode----------------------------
439 // Load a long from unaligned memory
440 class LoadL_unalignedNode : public LoadLNode {
441 public:
442 LoadL_unalignedNode(Node *c, Node *mem, Node *adr, const TypePtr* at, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
443 : LoadLNode(c, mem, adr, at, TypeLong::LONG, mo, control_dependency) {}
444 virtual int Opcode() const;
445 };
446
447 //------------------------------LoadFNode--------------------------------------
448 // Load a float (64 bits) from memory
449 class LoadFNode : public LoadNode {
450 public:
451 LoadFNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const Type *t, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
452 : LoadNode(c, mem, adr, at, t, mo, control_dependency) {}
453 virtual int Opcode() const;
454 virtual uint ideal_reg() const { return Op_RegF; }
455 virtual int store_Opcode() const { return Op_StoreF; }
456 virtual BasicType memory_type() const { return T_FLOAT; }
457 };
458
459 //------------------------------LoadDNode--------------------------------------
460 // Load a double (64 bits) from memory
461 class LoadDNode : public LoadNode {
462 virtual uint hash() const { return LoadNode::hash() + _require_atomic_access; }
463 virtual bool cmp( const Node &n ) const {
464 return _require_atomic_access == ((LoadDNode&)n)._require_atomic_access
465 && LoadNode::cmp(n);
466 }
467 virtual uint size_of() const { return sizeof(*this); }
468 const bool _require_atomic_access; // is piecewise load forbidden?
469
470 public:
471 LoadDNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const Type *t,
472 MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest, bool require_atomic_access = false)
473 : LoadNode(c, mem, adr, at, t, mo, control_dependency), _require_atomic_access(require_atomic_access) {}
474 virtual int Opcode() const;
475 virtual uint ideal_reg() const { return Op_RegD; }
476 virtual int store_Opcode() const { return Op_StoreD; }
477 virtual BasicType memory_type() const { return T_DOUBLE; }
478 bool require_atomic_access() const { return _require_atomic_access; }
479
480 #ifndef PRODUCT
481 virtual void dump_spec(outputStream *st) const {
482 LoadNode::dump_spec(st);
483 if (_require_atomic_access) st->print(" Atomic!");
484 }
485 #endif
486 };
487
488 //------------------------------LoadD_unalignedNode----------------------------
489 // Load a double from unaligned memory
490 class LoadD_unalignedNode : public LoadDNode {
491 public:
492 LoadD_unalignedNode(Node *c, Node *mem, Node *adr, const TypePtr* at, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
493 : LoadDNode(c, mem, adr, at, Type::DOUBLE, mo, control_dependency) {}
494 virtual int Opcode() const;
495 };
496
497 //------------------------------LoadPNode--------------------------------------
498 // Load a pointer from memory (either object or array)
499 class LoadPNode : public LoadNode {
500 public:
501 LoadPNode(Node *c, Node *mem, Node *adr, const TypePtr *at, const TypePtr* t, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
502 : LoadNode(c, mem, adr, at, t, mo, control_dependency) {}
503 virtual int Opcode() const;
504 virtual uint ideal_reg() const { return Op_RegP; }
505 virtual int store_Opcode() const { return Op_StoreP; }
506 virtual BasicType memory_type() const { return T_ADDRESS; }
507 };
508
509
510 //------------------------------LoadNNode--------------------------------------
511 // Load a narrow oop from memory (either object or array)
512 class LoadNNode : public LoadNode {
513 public:
514 LoadNNode(Node *c, Node *mem, Node *adr, const TypePtr *at, const Type* t, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
515 : LoadNode(c, mem, adr, at, t, mo, control_dependency) {}
516 virtual int Opcode() const;
517 virtual uint ideal_reg() const { return Op_RegN; }
518 virtual int store_Opcode() const { return Op_StoreN; }
519 virtual BasicType memory_type() const { return T_NARROWOOP; }
520 };
521
522 //------------------------------LoadKlassNode----------------------------------
523 // Load a Klass from an object
524 class LoadKlassNode : public LoadPNode {
525 private:
526 LoadKlassNode(Node* mem, Node* adr, const TypePtr* at, const TypeKlassPtr* tk, MemOrd mo)
527 : LoadPNode(nullptr, mem, adr, at, tk, mo) {}
528
529 public:
530 virtual int Opcode() const;
531 virtual const Type* Value(PhaseGVN* phase) const;
532 virtual Node* Identity(PhaseGVN* phase);
533 virtual bool depends_only_on_test() const { return true; }
534
535 // Polymorphic factory method:
536 static Node* make(PhaseGVN& gvn, Node* mem, Node* adr, const TypePtr* at,
537 const TypeKlassPtr* tk = TypeInstKlassPtr::OBJECT);
538 };
539
540 //------------------------------LoadNKlassNode---------------------------------
541 // Load a narrow Klass from an object.
542 // With compact headers, the input address (adr) does not point at the exact
543 // header position where the (narrow) class pointer is located, but into the
544 // middle of the mark word (see oopDesc::klass_offset_in_bytes()). This node
545 // implicitly shifts the loaded value (markWord::klass_shift_at_offset bits) to
546 // extract the actual class pointer. C2's type system is agnostic on whether the
547 // input address directly points into the class pointer.
548 class LoadNKlassNode : public LoadNNode {
549 private:
550 friend Node* LoadKlassNode::make(PhaseGVN&, Node*, Node*, const TypePtr*, const TypeKlassPtr*);
551 LoadNKlassNode(Node* mem, Node* adr, const TypePtr* at, const TypeNarrowKlass* tk, MemOrd mo)
552 : LoadNNode(nullptr, mem, adr, at, tk, mo) {}
553
554 public:
555 virtual int Opcode() const;
556 virtual uint ideal_reg() const { return Op_RegN; }
557 virtual int store_Opcode() const { return Op_StoreNKlass; }
558 virtual BasicType memory_type() const { return T_NARROWKLASS; }
559
560 virtual const Type* Value(PhaseGVN* phase) const;
561 virtual Node* Identity(PhaseGVN* phase);
562 virtual bool depends_only_on_test() const { return true; }
563 };
564
565
566 //------------------------------StoreNode--------------------------------------
567 // Store value; requires Store, Address and Value
568 class StoreNode : public MemNode {
569 private:
570 // On platforms with weak memory ordering (e.g., PPC) we distinguish
571 // stores that can be reordered, and such requiring release semantics to
572 // adhere to the Java specification. The required behaviour is stored in
573 // this field.
574 const MemOrd _mo;
575 // Needed for proper cloning.
576 virtual uint size_of() const { return sizeof(*this); }
577 protected:
578 virtual bool cmp( const Node &n ) const;
579 virtual bool depends_only_on_test() const { return false; }
580
581 Node *Ideal_masked_input (PhaseGVN *phase, uint mask);
582 Node* Ideal_sign_extended_input(PhaseGVN* phase, int num_rejected_bits);
583
584 public:
585 // We must ensure that stores of object references will be visible
586 // only after the object's initialization. So the callers of this
587 // procedure must indicate that the store requires `release'
588 // semantics, if the stored value is an object reference that might
589 // point to a new object and may become externally visible.
590 StoreNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
591 : MemNode(c, mem, adr, at, val), _mo(mo) {
592 init_class_id(Class_Store);
593 }
594 StoreNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, Node *oop_store, MemOrd mo)
595 : MemNode(c, mem, adr, at, val, oop_store), _mo(mo) {
596 init_class_id(Class_Store);
597 }
598
599 inline bool is_unordered() const { return !is_release(); }
600 inline bool is_release() const {
601 assert((_mo == unordered || _mo == release), "unexpected");
602 return _mo == release;
603 }
604
605 // Conservatively release stores of object references in order to
606 // ensure visibility of object initialization.
607 static inline MemOrd release_if_reference(const BasicType t) {
608 #ifdef AARCH64
609 // AArch64 doesn't need a release store here because object
610 // initialization contains the necessary barriers.
611 return unordered;
612 #else
613 const MemOrd mo = (t == T_ARRAY ||
614 t == T_ADDRESS || // Might be the address of an object reference (`boxing').
615 t == T_OBJECT) ? release : unordered;
616 return mo;
617 #endif
618 }
619
620 // Polymorphic factory method
621 //
622 // We must ensure that stores of object references will be visible
623 // only after the object's initialization. So the callers of this
624 // procedure must indicate that the store requires `release'
625 // semantics, if the stored value is an object reference that might
626 // point to a new object and may become externally visible.
627 static StoreNode* make(PhaseGVN& gvn, Node* c, Node* mem, Node* adr,
628 const TypePtr* at, Node* val, BasicType bt,
629 MemOrd mo, bool require_atomic_access = false);
630
631 virtual uint hash() const; // Check the type
632
633 // If the store is to Field memory and the pointer is non-null, we can
634 // zero out the control input.
635 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
636
637 // Compute a new Type for this node. Basically we just do the pre-check,
638 // then call the virtual add() to set the type.
639 virtual const Type* Value(PhaseGVN* phase) const;
640
641 // Check for identity function on memory (Load then Store at same address)
642 virtual Node* Identity(PhaseGVN* phase);
643
644 // Do not match memory edge
645 virtual uint match_edge(uint idx) const;
646
647 virtual const Type *bottom_type() const; // returns Type::MEMORY
648
649 // Map a store opcode to its corresponding own opcode, trivially.
650 virtual int store_Opcode() const { return Opcode(); }
651
652 // have all possible loads of the value stored been optimized away?
653 bool value_never_loaded(PhaseValues* phase) const;
654
655 bool has_reinterpret_variant(const Type* vt);
656 Node* convert_to_reinterpret_store(PhaseGVN& gvn, Node* val, const Type* vt);
657
658 MemBarNode* trailing_membar() const;
659 };
660
661 //------------------------------StoreBNode-------------------------------------
662 // Store byte to memory
663 class StoreBNode : public StoreNode {
664 public:
665 StoreBNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
666 : StoreNode(c, mem, adr, at, val, mo) {}
667 virtual int Opcode() const;
668 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
669 virtual BasicType memory_type() const { return T_BYTE; }
670 };
671
672 //------------------------------StoreCNode-------------------------------------
673 // Store char/short to memory
674 class StoreCNode : public StoreNode {
675 public:
676 StoreCNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
677 : StoreNode(c, mem, adr, at, val, mo) {}
678 virtual int Opcode() const;
679 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
680 virtual BasicType memory_type() const { return T_CHAR; }
681 };
682
683 //------------------------------StoreINode-------------------------------------
684 // Store int to memory
685 class StoreINode : public StoreNode {
686 public:
687 StoreINode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
688 : StoreNode(c, mem, adr, at, val, mo) {}
689 virtual int Opcode() const;
690 virtual BasicType memory_type() const { return T_INT; }
691 };
692
693 //------------------------------StoreLNode-------------------------------------
694 // Store long to memory
695 class StoreLNode : public StoreNode {
696 virtual uint hash() const { return StoreNode::hash() + _require_atomic_access; }
697 virtual bool cmp( const Node &n ) const {
698 return _require_atomic_access == ((StoreLNode&)n)._require_atomic_access
699 && StoreNode::cmp(n);
700 }
701 virtual uint size_of() const { return sizeof(*this); }
702 const bool _require_atomic_access; // is piecewise store forbidden?
703
704 public:
705 StoreLNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo, bool require_atomic_access = false)
706 : StoreNode(c, mem, adr, at, val, mo), _require_atomic_access(require_atomic_access) {}
707 virtual int Opcode() const;
708 virtual BasicType memory_type() const { return T_LONG; }
709 bool require_atomic_access() const { return _require_atomic_access; }
710
711 #ifndef PRODUCT
712 virtual void dump_spec(outputStream *st) const {
713 StoreNode::dump_spec(st);
714 if (_require_atomic_access) st->print(" Atomic!");
715 }
716 #endif
717 };
718
719 //------------------------------StoreFNode-------------------------------------
720 // Store float to memory
721 class StoreFNode : public StoreNode {
722 public:
723 StoreFNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
724 : StoreNode(c, mem, adr, at, val, mo) {}
725 virtual int Opcode() const;
726 virtual BasicType memory_type() const { return T_FLOAT; }
727 };
728
729 //------------------------------StoreDNode-------------------------------------
730 // Store double to memory
731 class StoreDNode : public StoreNode {
732 virtual uint hash() const { return StoreNode::hash() + _require_atomic_access; }
733 virtual bool cmp( const Node &n ) const {
734 return _require_atomic_access == ((StoreDNode&)n)._require_atomic_access
735 && StoreNode::cmp(n);
736 }
737 virtual uint size_of() const { return sizeof(*this); }
738 const bool _require_atomic_access; // is piecewise store forbidden?
739 public:
740 StoreDNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val,
741 MemOrd mo, bool require_atomic_access = false)
742 : StoreNode(c, mem, adr, at, val, mo), _require_atomic_access(require_atomic_access) {}
743 virtual int Opcode() const;
744 virtual BasicType memory_type() const { return T_DOUBLE; }
745 bool require_atomic_access() const { return _require_atomic_access; }
746
747 #ifndef PRODUCT
748 virtual void dump_spec(outputStream *st) const {
749 StoreNode::dump_spec(st);
750 if (_require_atomic_access) st->print(" Atomic!");
751 }
752 #endif
753
754 };
755
756 //------------------------------StorePNode-------------------------------------
757 // Store pointer to memory
758 class StorePNode : public StoreNode {
759 public:
760 StorePNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
761 : StoreNode(c, mem, adr, at, val, mo) {}
762 virtual int Opcode() const;
763 virtual BasicType memory_type() const { return T_ADDRESS; }
764 };
765
766 //------------------------------StoreNNode-------------------------------------
767 // Store narrow oop to memory
768 class StoreNNode : public StoreNode {
769 public:
770 StoreNNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
771 : StoreNode(c, mem, adr, at, val, mo) {}
772 virtual int Opcode() const;
773 virtual BasicType memory_type() const { return T_NARROWOOP; }
774 };
775
776 //------------------------------StoreNKlassNode--------------------------------------
777 // Store narrow klass to memory
778 class StoreNKlassNode : public StoreNNode {
779 public:
780 StoreNKlassNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
781 : StoreNNode(c, mem, adr, at, val, mo) {}
782 virtual int Opcode() const;
783 virtual BasicType memory_type() const { return T_NARROWKLASS; }
784 };
785
786 //------------------------------SCMemProjNode---------------------------------------
787 // This class defines a projection of the memory state of a store conditional node.
788 // These nodes return a value, but also update memory.
789 class SCMemProjNode : public ProjNode {
790 public:
791 enum {SCMEMPROJCON = (uint)-2};
792 SCMemProjNode( Node *src) : ProjNode( src, SCMEMPROJCON) { }
793 virtual int Opcode() const;
794 virtual bool is_CFG() const { return false; }
795 virtual const Type *bottom_type() const {return Type::MEMORY;}
796 virtual const TypePtr *adr_type() const {
797 Node* ctrl = in(0);
798 if (ctrl == nullptr) return nullptr; // node is dead
799 return ctrl->in(MemNode::Memory)->adr_type();
800 }
801 virtual uint ideal_reg() const { return 0;} // memory projections don't have a register
802 virtual const Type* Value(PhaseGVN* phase) const;
803 #ifndef PRODUCT
804 virtual void dump_spec(outputStream *st) const {};
805 #endif
806 };
807
808 //------------------------------LoadStoreNode---------------------------
809 // Note: is_Mem() method returns 'true' for this class.
810 class LoadStoreNode : public Node {
811 private:
812 const Type* const _type; // What kind of value is loaded?
813 const TypePtr* _adr_type; // What kind of memory is being addressed?
814 uint8_t _barrier_data; // Bit field with barrier information
815 virtual uint size_of() const; // Size is bigger
816 public:
817 LoadStoreNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at, const Type* rt, uint required );
818 virtual bool depends_only_on_test() const { return false; }
819 virtual uint match_edge(uint idx) const { return idx == MemNode::Address || idx == MemNode::ValueIn; }
820
821 virtual const Type *bottom_type() const { return _type; }
822 virtual uint ideal_reg() const;
823 virtual const class TypePtr *adr_type() const { return _adr_type; } // returns bottom_type of address
824 virtual const Type* Value(PhaseGVN* phase) const;
825
826 bool result_not_used() const;
827 MemBarNode* trailing_membar() const;
828
829 uint8_t barrier_data() { return _barrier_data; }
830 void set_barrier_data(uint8_t barrier_data) { _barrier_data = barrier_data; }
831 };
832
833 class LoadStoreConditionalNode : public LoadStoreNode {
834 public:
835 enum {
836 ExpectedIn = MemNode::ValueIn+1 // One more input than MemNode
837 };
838 LoadStoreConditionalNode(Node *c, Node *mem, Node *adr, Node *val, Node *ex);
839 virtual const Type* Value(PhaseGVN* phase) const;
840 };
841
842 class CompareAndSwapNode : public LoadStoreConditionalNode {
843 private:
844 const MemNode::MemOrd _mem_ord;
845 public:
846 CompareAndSwapNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : LoadStoreConditionalNode(c, mem, adr, val, ex), _mem_ord(mem_ord) {}
847 MemNode::MemOrd order() const {
848 return _mem_ord;
849 }
850 virtual uint size_of() const { return sizeof(*this); }
851 };
852
853 class CompareAndExchangeNode : public LoadStoreNode {
854 private:
855 const MemNode::MemOrd _mem_ord;
856 public:
857 enum {
858 ExpectedIn = MemNode::ValueIn+1 // One more input than MemNode
859 };
860 CompareAndExchangeNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord, const TypePtr* at, const Type* t) :
861 LoadStoreNode(c, mem, adr, val, at, t, 5), _mem_ord(mem_ord) {
862 init_req(ExpectedIn, ex );
863 }
864
865 MemNode::MemOrd order() const {
866 return _mem_ord;
867 }
868 virtual uint size_of() const { return sizeof(*this); }
869 };
870
871 //------------------------------CompareAndSwapBNode---------------------------
872 class CompareAndSwapBNode : public CompareAndSwapNode {
873 public:
874 CompareAndSwapBNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
875 virtual int Opcode() const;
876 };
877
878 //------------------------------CompareAndSwapSNode---------------------------
879 class CompareAndSwapSNode : public CompareAndSwapNode {
880 public:
881 CompareAndSwapSNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
882 virtual int Opcode() const;
883 };
884
885 //------------------------------CompareAndSwapINode---------------------------
886 class CompareAndSwapINode : public CompareAndSwapNode {
887 public:
888 CompareAndSwapINode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
889 virtual int Opcode() const;
890 };
891
892 //------------------------------CompareAndSwapLNode---------------------------
893 class CompareAndSwapLNode : public CompareAndSwapNode {
894 public:
895 CompareAndSwapLNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
896 virtual int Opcode() const;
897 };
898
899 //------------------------------CompareAndSwapPNode---------------------------
900 class CompareAndSwapPNode : public CompareAndSwapNode {
901 public:
902 CompareAndSwapPNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
903 virtual int Opcode() const;
904 };
905
906 //------------------------------CompareAndSwapNNode---------------------------
907 class CompareAndSwapNNode : public CompareAndSwapNode {
908 public:
909 CompareAndSwapNNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
910 virtual int Opcode() const;
911 };
912
913 //------------------------------WeakCompareAndSwapBNode---------------------------
914 class WeakCompareAndSwapBNode : public CompareAndSwapNode {
915 public:
916 WeakCompareAndSwapBNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
917 virtual int Opcode() const;
918 };
919
920 //------------------------------WeakCompareAndSwapSNode---------------------------
921 class WeakCompareAndSwapSNode : public CompareAndSwapNode {
922 public:
923 WeakCompareAndSwapSNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
924 virtual int Opcode() const;
925 };
926
927 //------------------------------WeakCompareAndSwapINode---------------------------
928 class WeakCompareAndSwapINode : public CompareAndSwapNode {
929 public:
930 WeakCompareAndSwapINode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
931 virtual int Opcode() const;
932 };
933
934 //------------------------------WeakCompareAndSwapLNode---------------------------
935 class WeakCompareAndSwapLNode : public CompareAndSwapNode {
936 public:
937 WeakCompareAndSwapLNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
938 virtual int Opcode() const;
939 };
940
941 //------------------------------WeakCompareAndSwapPNode---------------------------
942 class WeakCompareAndSwapPNode : public CompareAndSwapNode {
943 public:
944 WeakCompareAndSwapPNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
945 virtual int Opcode() const;
946 };
947
948 //------------------------------WeakCompareAndSwapNNode---------------------------
949 class WeakCompareAndSwapNNode : public CompareAndSwapNode {
950 public:
951 WeakCompareAndSwapNNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
952 virtual int Opcode() const;
953 };
954
955 //------------------------------CompareAndExchangeBNode---------------------------
956 class CompareAndExchangeBNode : public CompareAndExchangeNode {
957 public:
958 CompareAndExchangeBNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, const TypePtr* at, MemNode::MemOrd mem_ord) : CompareAndExchangeNode(c, mem, adr, val, ex, mem_ord, at, TypeInt::BYTE) { }
959 virtual int Opcode() const;
960 };
961
962
963 //------------------------------CompareAndExchangeSNode---------------------------
964 class CompareAndExchangeSNode : public CompareAndExchangeNode {
965 public:
966 CompareAndExchangeSNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, const TypePtr* at, MemNode::MemOrd mem_ord) : CompareAndExchangeNode(c, mem, adr, val, ex, mem_ord, at, TypeInt::SHORT) { }
967 virtual int Opcode() const;
968 };
969
970 //------------------------------CompareAndExchangeLNode---------------------------
971 class CompareAndExchangeLNode : public CompareAndExchangeNode {
972 public:
973 CompareAndExchangeLNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, const TypePtr* at, MemNode::MemOrd mem_ord) : CompareAndExchangeNode(c, mem, adr, val, ex, mem_ord, at, TypeLong::LONG) { }
974 virtual int Opcode() const;
975 };
976
977
978 //------------------------------CompareAndExchangeINode---------------------------
979 class CompareAndExchangeINode : public CompareAndExchangeNode {
980 public:
981 CompareAndExchangeINode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, const TypePtr* at, MemNode::MemOrd mem_ord) : CompareAndExchangeNode(c, mem, adr, val, ex, mem_ord, at, TypeInt::INT) { }
982 virtual int Opcode() const;
983 };
984
985
986 //------------------------------CompareAndExchangePNode---------------------------
987 class CompareAndExchangePNode : public CompareAndExchangeNode {
988 public:
989 CompareAndExchangePNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, const TypePtr* at, const Type* t, MemNode::MemOrd mem_ord) : CompareAndExchangeNode(c, mem, adr, val, ex, mem_ord, at, t) { }
990 virtual int Opcode() const;
991 };
992
993 //------------------------------CompareAndExchangeNNode---------------------------
994 class CompareAndExchangeNNode : public CompareAndExchangeNode {
995 public:
996 CompareAndExchangeNNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, const TypePtr* at, const Type* t, MemNode::MemOrd mem_ord) : CompareAndExchangeNode(c, mem, adr, val, ex, mem_ord, at, t) { }
997 virtual int Opcode() const;
998 };
999
1000 //------------------------------GetAndAddBNode---------------------------
1001 class GetAndAddBNode : public LoadStoreNode {
1002 public:
1003 GetAndAddBNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeInt::BYTE, 4) { }
1004 virtual int Opcode() const;
1005 };
1006
1007 //------------------------------GetAndAddSNode---------------------------
1008 class GetAndAddSNode : public LoadStoreNode {
1009 public:
1010 GetAndAddSNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeInt::SHORT, 4) { }
1011 virtual int Opcode() const;
1012 };
1013
1014 //------------------------------GetAndAddINode---------------------------
1015 class GetAndAddINode : public LoadStoreNode {
1016 public:
1017 GetAndAddINode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeInt::INT, 4) { }
1018 virtual int Opcode() const;
1019 };
1020
1021 //------------------------------GetAndAddLNode---------------------------
1022 class GetAndAddLNode : public LoadStoreNode {
1023 public:
1024 GetAndAddLNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeLong::LONG, 4) { }
1025 virtual int Opcode() const;
1026 };
1027
1028 //------------------------------GetAndSetBNode---------------------------
1029 class GetAndSetBNode : public LoadStoreNode {
1030 public:
1031 GetAndSetBNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeInt::BYTE, 4) { }
1032 virtual int Opcode() const;
1033 };
1034
1035 //------------------------------GetAndSetSNode---------------------------
1036 class GetAndSetSNode : public LoadStoreNode {
1037 public:
1038 GetAndSetSNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeInt::SHORT, 4) { }
1039 virtual int Opcode() const;
1040 };
1041
1042 //------------------------------GetAndSetINode---------------------------
1043 class GetAndSetINode : public LoadStoreNode {
1044 public:
1045 GetAndSetINode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeInt::INT, 4) { }
1046 virtual int Opcode() const;
1047 };
1048
1049 //------------------------------GetAndSetLNode---------------------------
1050 class GetAndSetLNode : public LoadStoreNode {
1051 public:
1052 GetAndSetLNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeLong::LONG, 4) { }
1053 virtual int Opcode() const;
1054 };
1055
1056 //------------------------------GetAndSetPNode---------------------------
1057 class GetAndSetPNode : public LoadStoreNode {
1058 public:
1059 GetAndSetPNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at, const Type* t ) : LoadStoreNode(c, mem, adr, val, at, t, 4) { }
1060 virtual int Opcode() const;
1061 };
1062
1063 //------------------------------GetAndSetNNode---------------------------
1064 class GetAndSetNNode : public LoadStoreNode {
1065 public:
1066 GetAndSetNNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at, const Type* t ) : LoadStoreNode(c, mem, adr, val, at, t, 4) { }
1067 virtual int Opcode() const;
1068 };
1069
1070 //------------------------------ClearArray-------------------------------------
1071 class ClearArrayNode: public Node {
1072 private:
1073 bool _is_large;
1074 public:
1075 ClearArrayNode( Node *ctrl, Node *arymem, Node *word_cnt, Node *base, bool is_large)
1076 : Node(ctrl,arymem,word_cnt,base), _is_large(is_large) {
1077 init_class_id(Class_ClearArray);
1078 }
1079 virtual int Opcode() const;
1080 virtual const Type *bottom_type() const { return Type::MEMORY; }
1081 // ClearArray modifies array elements, and so affects only the
1082 // array memory addressed by the bottom_type of its base address.
1083 virtual const class TypePtr *adr_type() const;
1084 virtual Node* Identity(PhaseGVN* phase);
1085 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
1086 virtual uint match_edge(uint idx) const;
1087 bool is_large() const { return _is_large; }
1088
1089 // Clear the given area of an object or array.
1090 // The start offset must always be aligned mod BytesPerInt.
1091 // The end offset must always be aligned mod BytesPerLong.
1092 // Return the new memory.
1093 static Node* clear_memory(Node* control, Node* mem, Node* dest,
1094 intptr_t start_offset,
1095 intptr_t end_offset,
1096 PhaseGVN* phase);
1097 static Node* clear_memory(Node* control, Node* mem, Node* dest,
1098 intptr_t start_offset,
1099 Node* end_offset,
1100 PhaseGVN* phase);
1101 static Node* clear_memory(Node* control, Node* mem, Node* dest,
1102 Node* start_offset,
1103 Node* end_offset,
1104 PhaseGVN* phase);
1105 // Return allocation input memory edge if it is different instance
1106 // or itself if it is the one we are looking for.
1107 static bool step_through(Node** np, uint instance_id, PhaseValues* phase);
1108 };
1109
1110 //------------------------------MemBar-----------------------------------------
1111 // There are different flavors of Memory Barriers to match the Java Memory
1112 // Model. Monitor-enter and volatile-load act as Acquires: no following ref
1113 // can be moved to before them. We insert a MemBar-Acquire after a FastLock or
1114 // volatile-load. Monitor-exit and volatile-store act as Release: no
1115 // preceding ref can be moved to after them. We insert a MemBar-Release
1116 // before a FastUnlock or volatile-store. All volatiles need to be
1117 // serialized, so we follow all volatile-stores with a MemBar-Volatile to
1118 // separate it from any following volatile-load.
1119 class MemBarNode: public MultiNode {
1120 virtual uint hash() const ; // { return NO_HASH; }
1121 virtual bool cmp( const Node &n ) const ; // Always fail, except on self
1122
1123 virtual uint size_of() const { return sizeof(*this); }
1124 // Memory type this node is serializing. Usually either rawptr or bottom.
1125 const TypePtr* _adr_type;
1126
1127 // How is this membar related to a nearby memory access?
1128 enum {
1129 Standalone,
1130 TrailingLoad,
1131 TrailingStore,
1132 LeadingStore,
1133 TrailingLoadStore,
1134 LeadingLoadStore,
1135 TrailingPartialArrayCopy
1136 } _kind;
1137
1138 #ifdef ASSERT
1139 uint _pair_idx;
1140 #endif
1141
1142 public:
1143 enum {
1144 Precedent = TypeFunc::Parms // optional edge to force precedence
1145 };
1146 MemBarNode(Compile* C, int alias_idx, Node* precedent);
1147 virtual int Opcode() const = 0;
1148 virtual const class TypePtr *adr_type() const { return _adr_type; }
1149 virtual const Type* Value(PhaseGVN* phase) const;
1150 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
1151 virtual uint match_edge(uint idx) const { return 0; }
1152 virtual const Type *bottom_type() const { return TypeTuple::MEMBAR; }
1153 virtual Node *match( const ProjNode *proj, const Matcher *m );
1154 // Factory method. Builds a wide or narrow membar.
1155 // Optional 'precedent' becomes an extra edge if not null.
1156 static MemBarNode* make(Compile* C, int opcode,
1157 int alias_idx = Compile::AliasIdxBot,
1158 Node* precedent = nullptr);
1159
1160 MemBarNode* trailing_membar() const;
1161 MemBarNode* leading_membar() const;
1162
1163 void set_trailing_load() { _kind = TrailingLoad; }
1164 bool trailing_load() const { return _kind == TrailingLoad; }
1165 bool trailing_store() const { return _kind == TrailingStore; }
1166 bool leading_store() const { return _kind == LeadingStore; }
1167 bool trailing_load_store() const { return _kind == TrailingLoadStore; }
1168 bool leading_load_store() const { return _kind == LeadingLoadStore; }
1169 bool trailing() const { return _kind == TrailingLoad || _kind == TrailingStore || _kind == TrailingLoadStore; }
1170 bool leading() const { return _kind == LeadingStore || _kind == LeadingLoadStore; }
1171 bool standalone() const { return _kind == Standalone; }
1172 void set_trailing_partial_array_copy() { _kind = TrailingPartialArrayCopy; }
1173 bool trailing_partial_array_copy() const { return _kind == TrailingPartialArrayCopy; }
1174
1175 static void set_store_pair(MemBarNode* leading, MemBarNode* trailing);
1176 static void set_load_store_pair(MemBarNode* leading, MemBarNode* trailing);
1177
1178 void remove(PhaseIterGVN *igvn);
1179 };
1180
1181 // "Acquire" - no following ref can move before (but earlier refs can
1182 // follow, like an early Load stalled in cache). Requires multi-cpu
1183 // visibility. Inserted after a volatile load.
1184 class MemBarAcquireNode: public MemBarNode {
1185 public:
1186 MemBarAcquireNode(Compile* C, int alias_idx, Node* precedent)
1187 : MemBarNode(C, alias_idx, precedent) {}
1188 virtual int Opcode() const;
1189 };
1190
1191 // "Acquire" - no following ref can move before (but earlier refs can
1192 // follow, like an early Load stalled in cache). Requires multi-cpu
1193 // visibility. Inserted independent of any load, as required
1194 // for intrinsic Unsafe.loadFence().
1195 class LoadFenceNode: public MemBarNode {
1196 public:
1197 LoadFenceNode(Compile* C, int alias_idx, Node* precedent)
1198 : MemBarNode(C, alias_idx, precedent) {}
1199 virtual int Opcode() const;
1200 };
1201
1202 // "Release" - no earlier ref can move after (but later refs can move
1203 // up, like a speculative pipelined cache-hitting Load). Requires
1204 // multi-cpu visibility. Inserted before a volatile store.
1205 class MemBarReleaseNode: public MemBarNode {
1206 public:
1207 MemBarReleaseNode(Compile* C, int alias_idx, Node* precedent)
1208 : MemBarNode(C, alias_idx, precedent) {}
1209 virtual int Opcode() const;
1210 };
1211
1212 // "Release" - no earlier ref can move after (but later refs can move
1213 // up, like a speculative pipelined cache-hitting Load). Requires
1214 // multi-cpu visibility. Inserted independent of any store, as required
1215 // for intrinsic Unsafe.storeFence().
1216 class StoreFenceNode: public MemBarNode {
1217 public:
1218 StoreFenceNode(Compile* C, int alias_idx, Node* precedent)
1219 : MemBarNode(C, alias_idx, precedent) {}
1220 virtual int Opcode() const;
1221 };
1222
1223 // "Acquire" - no following ref can move before (but earlier refs can
1224 // follow, like an early Load stalled in cache). Requires multi-cpu
1225 // visibility. Inserted after a FastLock.
1226 class MemBarAcquireLockNode: public MemBarNode {
1227 public:
1228 MemBarAcquireLockNode(Compile* C, int alias_idx, Node* precedent)
1229 : MemBarNode(C, alias_idx, precedent) {}
1230 virtual int Opcode() const;
1231 };
1232
1233 // "Release" - no earlier ref can move after (but later refs can move
1234 // up, like a speculative pipelined cache-hitting Load). Requires
1235 // multi-cpu visibility. Inserted before a FastUnLock.
1236 class MemBarReleaseLockNode: public MemBarNode {
1237 public:
1238 MemBarReleaseLockNode(Compile* C, int alias_idx, Node* precedent)
1239 : MemBarNode(C, alias_idx, precedent) {}
1240 virtual int Opcode() const;
1241 };
1242
1243 class MemBarStoreStoreNode: public MemBarNode {
1244 public:
1245 MemBarStoreStoreNode(Compile* C, int alias_idx, Node* precedent)
1246 : MemBarNode(C, alias_idx, precedent) {
1247 init_class_id(Class_MemBarStoreStore);
1248 }
1249 virtual int Opcode() const;
1250 };
1251
1252 class StoreStoreFenceNode: public MemBarNode {
1253 public:
1254 StoreStoreFenceNode(Compile* C, int alias_idx, Node* precedent)
1255 : MemBarNode(C, alias_idx, precedent) {}
1256 virtual int Opcode() const;
1257 };
1258
1259 // Ordering between a volatile store and a following volatile load.
1260 // Requires multi-CPU visibility?
1261 class MemBarVolatileNode: public MemBarNode {
1262 public:
1263 MemBarVolatileNode(Compile* C, int alias_idx, Node* precedent)
1264 : MemBarNode(C, alias_idx, precedent) {}
1265 virtual int Opcode() const;
1266 };
1267
1268 // Ordering within the same CPU. Used to order unsafe memory references
1269 // inside the compiler when we lack alias info. Not needed "outside" the
1270 // compiler because the CPU does all the ordering for us.
1271 class MemBarCPUOrderNode: public MemBarNode {
1272 public:
1273 MemBarCPUOrderNode(Compile* C, int alias_idx, Node* precedent)
1274 : MemBarNode(C, alias_idx, precedent) {}
1275 virtual int Opcode() const;
1276 virtual uint ideal_reg() const { return 0; } // not matched in the AD file
1277 };
1278
1279 class OnSpinWaitNode: public MemBarNode {
1280 public:
1281 OnSpinWaitNode(Compile* C, int alias_idx, Node* precedent)
1282 : MemBarNode(C, alias_idx, precedent) {}
1283 virtual int Opcode() const;
1284 };
1285
1286 // Isolation of object setup after an AllocateNode and before next safepoint.
1287 // (See comment in memnode.cpp near InitializeNode::InitializeNode for semantics.)
1288 class InitializeNode: public MemBarNode {
1289 friend class AllocateNode;
1290
1291 enum {
1292 Incomplete = 0,
1293 Complete = 1,
1294 WithArraycopy = 2
1295 };
1296 int _is_complete;
1297
1298 bool _does_not_escape;
1299
1300 public:
1301 enum {
1302 Control = TypeFunc::Control,
1303 Memory = TypeFunc::Memory, // MergeMem for states affected by this op
1304 RawAddress = TypeFunc::Parms+0, // the newly-allocated raw address
1305 RawStores = TypeFunc::Parms+1 // zero or more stores (or TOP)
1306 };
1307
1308 InitializeNode(Compile* C, int adr_type, Node* rawoop);
1309 virtual int Opcode() const;
1310 virtual uint size_of() const { return sizeof(*this); }
1311 virtual uint ideal_reg() const { return 0; } // not matched in the AD file
1312 virtual const RegMask &in_RegMask(uint) const; // mask for RawAddress
1313
1314 // Manage incoming memory edges via a MergeMem on in(Memory):
1315 Node* memory(uint alias_idx);
1316
1317 // The raw memory edge coming directly from the Allocation.
1318 // The contents of this memory are *always* all-zero-bits.
1319 Node* zero_memory() { return memory(Compile::AliasIdxRaw); }
1320
1321 // Return the corresponding allocation for this initialization (or null if none).
1322 // (Note: Both InitializeNode::allocation and AllocateNode::initialization
1323 // are defined in graphKit.cpp, which sets up the bidirectional relation.)
1324 AllocateNode* allocation();
1325
1326 // Anything other than zeroing in this init?
1327 bool is_non_zero();
1328
1329 // An InitializeNode must completed before macro expansion is done.
1330 // Completion requires that the AllocateNode must be followed by
1331 // initialization of the new memory to zero, then to any initializers.
1332 bool is_complete() { return _is_complete != Incomplete; }
1333 bool is_complete_with_arraycopy() { return (_is_complete & WithArraycopy) != 0; }
1334
1335 // Mark complete. (Must not yet be complete.)
1336 void set_complete(PhaseGVN* phase);
1337 void set_complete_with_arraycopy() { _is_complete = Complete | WithArraycopy; }
1338
1339 bool does_not_escape() { return _does_not_escape; }
1340 void set_does_not_escape() { _does_not_escape = true; }
1341
1342 #ifdef ASSERT
1343 // ensure all non-degenerate stores are ordered and non-overlapping
1344 bool stores_are_sane(PhaseValues* phase);
1345 #endif //ASSERT
1346
1347 // See if this store can be captured; return offset where it initializes.
1348 // Return 0 if the store cannot be moved (any sort of problem).
1349 intptr_t can_capture_store(StoreNode* st, PhaseGVN* phase, bool can_reshape);
1350
1351 // Capture another store; reformat it to write my internal raw memory.
1352 // Return the captured copy, else null if there is some sort of problem.
1353 Node* capture_store(StoreNode* st, intptr_t start, PhaseGVN* phase, bool can_reshape);
1354
1355 // Find captured store which corresponds to the range [start..start+size).
1356 // Return my own memory projection (meaning the initial zero bits)
1357 // if there is no such store. Return null if there is a problem.
1358 Node* find_captured_store(intptr_t start, int size_in_bytes, PhaseValues* phase);
1359
1360 // Called when the associated AllocateNode is expanded into CFG.
1361 Node* complete_stores(Node* rawctl, Node* rawmem, Node* rawptr,
1362 intptr_t header_size, Node* size_in_bytes,
1363 PhaseIterGVN* phase);
1364
1365 private:
1366 void remove_extra_zeroes();
1367
1368 // Find out where a captured store should be placed (or already is placed).
1369 int captured_store_insertion_point(intptr_t start, int size_in_bytes,
1370 PhaseValues* phase);
1371
1372 static intptr_t get_store_offset(Node* st, PhaseValues* phase);
1373
1374 Node* make_raw_address(intptr_t offset, PhaseGVN* phase);
1375
1376 bool detect_init_independence(Node* value, PhaseGVN* phase);
1377
1378 void coalesce_subword_stores(intptr_t header_size, Node* size_in_bytes,
1379 PhaseGVN* phase);
1380
1381 intptr_t find_next_fullword_store(uint i, PhaseGVN* phase);
1382 };
1383
1384 //------------------------------MergeMem---------------------------------------
1385 // (See comment in memnode.cpp near MergeMemNode::MergeMemNode for semantics.)
1386 class MergeMemNode: public Node {
1387 virtual uint hash() const ; // { return NO_HASH; }
1388 virtual bool cmp( const Node &n ) const ; // Always fail, except on self
1389 friend class MergeMemStream;
1390 MergeMemNode(Node* def); // clients use MergeMemNode::make
1391
1392 public:
1393 // If the input is a whole memory state, clone it with all its slices intact.
1394 // Otherwise, make a new memory state with just that base memory input.
1395 // In either case, the result is a newly created MergeMem.
1396 static MergeMemNode* make(Node* base_memory);
1397
1398 virtual int Opcode() const;
1399 virtual Node* Identity(PhaseGVN* phase);
1400 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
1401 virtual uint ideal_reg() const { return NotAMachineReg; }
1402 virtual uint match_edge(uint idx) const { return 0; }
1403 virtual const RegMask &out_RegMask() const;
1404 virtual const Type *bottom_type() const { return Type::MEMORY; }
1405 virtual const TypePtr *adr_type() const { return TypePtr::BOTTOM; }
1406 // sparse accessors
1407 // Fetch the previously stored "set_memory_at", or else the base memory.
1408 // (Caller should clone it if it is a phi-nest.)
1409 Node* memory_at(uint alias_idx) const;
1410 // set the memory, regardless of its previous value
1411 void set_memory_at(uint alias_idx, Node* n);
1412 // the "base" is the memory that provides the non-finite support
1413 Node* base_memory() const { return in(Compile::AliasIdxBot); }
1414 // warning: setting the base can implicitly set any of the other slices too
1415 void set_base_memory(Node* def);
1416 // sentinel value which denotes a copy of the base memory:
1417 Node* empty_memory() const { return in(Compile::AliasIdxTop); }
1418 static Node* make_empty_memory(); // where the sentinel comes from
1419 bool is_empty_memory(Node* n) const { assert((n == empty_memory()) == n->is_top(), "sanity"); return n->is_top(); }
1420 // hook for the iterator, to perform any necessary setup
1421 void iteration_setup(const MergeMemNode* other = nullptr);
1422 // push sentinels until I am at least as long as the other (semantic no-op)
1423 void grow_to_match(const MergeMemNode* other);
1424 bool verify_sparse() const PRODUCT_RETURN0;
1425 #ifndef PRODUCT
1426 virtual void dump_spec(outputStream *st) const;
1427 #endif
1428 };
1429
1430 class MergeMemStream : public StackObj {
1431 private:
1432 MergeMemNode* _mm;
1433 const MergeMemNode* _mm2; // optional second guy, contributes non-empty iterations
1434 Node* _mm_base; // loop-invariant base memory of _mm
1435 int _idx;
1436 int _cnt;
1437 Node* _mem;
1438 Node* _mem2;
1439 int _cnt2;
1440
1441 void init(MergeMemNode* mm, const MergeMemNode* mm2 = nullptr) {
1442 // subsume_node will break sparseness at times, whenever a memory slice
1443 // folds down to a copy of the base ("fat") memory. In such a case,
1444 // the raw edge will update to base, although it should be top.
1445 // This iterator will recognize either top or base_memory as an
1446 // "empty" slice. See is_empty, is_empty2, and next below.
1447 //
1448 // The sparseness property is repaired in MergeMemNode::Ideal.
1449 // As long as access to a MergeMem goes through this iterator
1450 // or the memory_at accessor, flaws in the sparseness will
1451 // never be observed.
1452 //
1453 // Also, iteration_setup repairs sparseness.
1454 assert(mm->verify_sparse(), "please, no dups of base");
1455 assert(mm2==nullptr || mm2->verify_sparse(), "please, no dups of base");
1456
1457 _mm = mm;
1458 _mm_base = mm->base_memory();
1459 _mm2 = mm2;
1460 _cnt = mm->req();
1461 _idx = Compile::AliasIdxBot-1; // start at the base memory
1462 _mem = nullptr;
1463 _mem2 = nullptr;
1464 }
1465
1466 #ifdef ASSERT
1467 Node* check_memory() const {
1468 if (at_base_memory())
1469 return _mm->base_memory();
1470 else if ((uint)_idx < _mm->req() && !_mm->in(_idx)->is_top())
1471 return _mm->memory_at(_idx);
1472 else
1473 return _mm_base;
1474 }
1475 Node* check_memory2() const {
1476 return at_base_memory()? _mm2->base_memory(): _mm2->memory_at(_idx);
1477 }
1478 #endif
1479
1480 static bool match_memory(Node* mem, const MergeMemNode* mm, int idx) PRODUCT_RETURN0;
1481 void assert_synch() const {
1482 assert(!_mem || _idx >= _cnt || match_memory(_mem, _mm, _idx),
1483 "no side-effects except through the stream");
1484 }
1485
1486 public:
1487
1488 // expected usages:
1489 // for (MergeMemStream mms(mem->is_MergeMem()); next_non_empty(); ) { ... }
1490 // for (MergeMemStream mms(mem1, mem2); next_non_empty2(); ) { ... }
1491
1492 // iterate over one merge
1493 MergeMemStream(MergeMemNode* mm) {
1494 mm->iteration_setup();
1495 init(mm);
1496 debug_only(_cnt2 = 999);
1497 }
1498 // iterate in parallel over two merges
1499 // only iterates through non-empty elements of mm2
1500 MergeMemStream(MergeMemNode* mm, const MergeMemNode* mm2) {
1501 assert(mm2, "second argument must be a MergeMem also");
1502 ((MergeMemNode*)mm2)->iteration_setup(); // update hidden state
1503 mm->iteration_setup(mm2);
1504 init(mm, mm2);
1505 _cnt2 = mm2->req();
1506 }
1507 #ifdef ASSERT
1508 ~MergeMemStream() {
1509 assert_synch();
1510 }
1511 #endif
1512
1513 MergeMemNode* all_memory() const {
1514 return _mm;
1515 }
1516 Node* base_memory() const {
1517 assert(_mm_base == _mm->base_memory(), "no update to base memory, please");
1518 return _mm_base;
1519 }
1520 const MergeMemNode* all_memory2() const {
1521 assert(_mm2 != nullptr, "");
1522 return _mm2;
1523 }
1524 bool at_base_memory() const {
1525 return _idx == Compile::AliasIdxBot;
1526 }
1527 int alias_idx() const {
1528 assert(_mem, "must call next 1st");
1529 return _idx;
1530 }
1531
1532 const TypePtr* adr_type() const {
1533 return Compile::current()->get_adr_type(alias_idx());
1534 }
1535
1536 const TypePtr* adr_type(Compile* C) const {
1537 return C->get_adr_type(alias_idx());
1538 }
1539 bool is_empty() const {
1540 assert(_mem, "must call next 1st");
1541 assert(_mem->is_top() == (_mem==_mm->empty_memory()), "correct sentinel");
1542 return _mem->is_top();
1543 }
1544 bool is_empty2() const {
1545 assert(_mem2, "must call next 1st");
1546 assert(_mem2->is_top() == (_mem2==_mm2->empty_memory()), "correct sentinel");
1547 return _mem2->is_top();
1548 }
1549 Node* memory() const {
1550 assert(!is_empty(), "must not be empty");
1551 assert_synch();
1552 return _mem;
1553 }
1554 // get the current memory, regardless of empty or non-empty status
1555 Node* force_memory() const {
1556 assert(!is_empty() || !at_base_memory(), "");
1557 // Use _mm_base to defend against updates to _mem->base_memory().
1558 Node *mem = _mem->is_top() ? _mm_base : _mem;
1559 assert(mem == check_memory(), "");
1560 return mem;
1561 }
1562 Node* memory2() const {
1563 assert(_mem2 == check_memory2(), "");
1564 return _mem2;
1565 }
1566 void set_memory(Node* mem) {
1567 if (at_base_memory()) {
1568 // Note that this does not change the invariant _mm_base.
1569 _mm->set_base_memory(mem);
1570 } else {
1571 _mm->set_memory_at(_idx, mem);
1572 }
1573 _mem = mem;
1574 assert_synch();
1575 }
1576
1577 // Recover from a side effect to the MergeMemNode.
1578 void set_memory() {
1579 _mem = _mm->in(_idx);
1580 }
1581
1582 bool next() { return next(false); }
1583 bool next2() { return next(true); }
1584
1585 bool next_non_empty() { return next_non_empty(false); }
1586 bool next_non_empty2() { return next_non_empty(true); }
1587 // next_non_empty2 can yield states where is_empty() is true
1588
1589 private:
1590 // find the next item, which might be empty
1591 bool next(bool have_mm2) {
1592 assert((_mm2 != nullptr) == have_mm2, "use other next");
1593 assert_synch();
1594 if (++_idx < _cnt) {
1595 // Note: This iterator allows _mm to be non-sparse.
1596 // It behaves the same whether _mem is top or base_memory.
1597 _mem = _mm->in(_idx);
1598 if (have_mm2)
1599 _mem2 = _mm2->in((_idx < _cnt2) ? _idx : Compile::AliasIdxTop);
1600 return true;
1601 }
1602 return false;
1603 }
1604
1605 // find the next non-empty item
1606 bool next_non_empty(bool have_mm2) {
1607 while (next(have_mm2)) {
1608 if (!is_empty()) {
1609 // make sure _mem2 is filled in sensibly
1610 if (have_mm2 && _mem2->is_top()) _mem2 = _mm2->base_memory();
1611 return true;
1612 } else if (have_mm2 && !is_empty2()) {
1613 return true; // is_empty() == true
1614 }
1615 }
1616 return false;
1617 }
1618 };
1619
1620 // cachewb node for guaranteeing writeback of the cache line at a
1621 // given address to (non-volatile) RAM
1622 class CacheWBNode : public Node {
1623 public:
1624 CacheWBNode(Node *ctrl, Node *mem, Node *addr) : Node(ctrl, mem, addr) {}
1625 virtual int Opcode() const;
1626 virtual uint ideal_reg() const { return NotAMachineReg; }
1627 virtual uint match_edge(uint idx) const { return (idx == 2); }
1628 virtual const TypePtr *adr_type() const { return TypePtr::BOTTOM; }
1629 virtual const Type *bottom_type() const { return Type::MEMORY; }
1630 };
1631
1632 // cachewb pre sync node for ensuring that writebacks are serialised
1633 // relative to preceding or following stores
1634 class CacheWBPreSyncNode : public Node {
1635 public:
1636 CacheWBPreSyncNode(Node *ctrl, Node *mem) : Node(ctrl, mem) {}
1637 virtual int Opcode() const;
1638 virtual uint ideal_reg() const { return NotAMachineReg; }
1639 virtual uint match_edge(uint idx) const { return false; }
1640 virtual const TypePtr *adr_type() const { return TypePtr::BOTTOM; }
1641 virtual const Type *bottom_type() const { return Type::MEMORY; }
1642 };
1643
1644 // cachewb pre sync node for ensuring that writebacks are serialised
1645 // relative to preceding or following stores
1646 class CacheWBPostSyncNode : public Node {
1647 public:
1648 CacheWBPostSyncNode(Node *ctrl, Node *mem) : Node(ctrl, mem) {}
1649 virtual int Opcode() const;
1650 virtual uint ideal_reg() const { return NotAMachineReg; }
1651 virtual uint match_edge(uint idx) const { return false; }
1652 virtual const TypePtr *adr_type() const { return TypePtr::BOTTOM; }
1653 virtual const Type *bottom_type() const { return Type::MEMORY; }
1654 };
1655
1656 //------------------------------Prefetch---------------------------------------
1657
1658 // Allocation prefetch which may fault, TLAB size have to be adjusted.
1659 class PrefetchAllocationNode : public Node {
1660 public:
1661 PrefetchAllocationNode(Node *mem, Node *adr) : Node(nullptr,mem,adr) {}
1662 virtual int Opcode() const;
1663 virtual uint ideal_reg() const { return NotAMachineReg; }
1664 virtual uint match_edge(uint idx) const { return idx==2; }
1665 virtual const Type *bottom_type() const { return ( AllocatePrefetchStyle == 3 ) ? Type::MEMORY : Type::ABIO; }
1666 };
1667
1668 #endif // SHARE_OPTO_MEMNODE_HPP