1 /*
2 * Copyright (c) 1997, 2023, Oracle and/or its affiliates. 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.
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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
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23 */
24
25 #ifndef SHARE_OPTO_MEMNODE_HPP
26 #define SHARE_OPTO_MEMNODE_HPP
27
28 #include "opto/multnode.hpp"
29 #include "opto/node.hpp"
30 #include "opto/opcodes.hpp"
31 #include "opto/type.hpp"
32
33 // Portions of code courtesy of Clifford Click
34
35 class MultiNode;
36 class PhaseCCP;
37 class PhaseTransform;
38
39 //------------------------------MemNode----------------------------------------
40 // Load or Store, possibly throwing a null pointer exception
41 class MemNode : public Node {
42 private:
43 bool _unaligned_access; // Unaligned access from unsafe
44 bool _mismatched_access; // Mismatched access from unsafe: byte read in integer array for instance
45 bool _unsafe_access; // Access of unsafe origin.
46 uint8_t _barrier_data; // Bit field with barrier information
47
48 protected:
49 #ifdef ASSERT
50 const TypePtr* _adr_type; // What kind of memory is being addressed?
51 #endif
52 virtual uint size_of() const;
53 public:
54 enum { Control, // When is it safe to do this load?
55 Memory, // Chunk of memory is being loaded from
56 Address, // Actually address, derived from base
57 ValueIn, // Value to store
58 OopStore // Preceding oop store, only in StoreCM
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 // This one should probably be a phase-specific function:
109 static bool all_controls_dominate(Node* dom, Node* sub);
110
111 virtual const class TypePtr *adr_type() const; // returns bottom_type of address
112
113 // Shared code for Ideal methods:
114 Node *Ideal_common(PhaseGVN *phase, bool can_reshape); // Return -1 for short-circuit null.
115
116 // Helper function for adr_type() implementations.
117 static const TypePtr* calculate_adr_type(const Type* t, const TypePtr* cross_check = nullptr);
118
119 // Raw access function, to allow copying of adr_type efficiently in
120 // product builds and retain the debug info for debug builds.
121 const TypePtr *raw_adr_type() const {
122 #ifdef ASSERT
123 return _adr_type;
124 #else
125 return 0;
126 #endif
127 }
128
129 // Map a load or store opcode to its corresponding store opcode.
130 // (Return -1 if unknown.)
131 virtual int store_Opcode() const { return -1; }
132
133 // What is the type of the value in memory? (T_VOID mean "unspecified".)
134 virtual BasicType memory_type() const = 0;
135 virtual int memory_size() const {
136 #ifdef ASSERT
137 return type2aelembytes(memory_type(), true);
138 #else
139 return type2aelembytes(memory_type());
140 #endif
141 }
142
143 uint8_t barrier_data() { return _barrier_data; }
144 void set_barrier_data(uint8_t barrier_data) { _barrier_data = barrier_data; }
145
146 // Search through memory states which precede this node (load or store).
147 // Look for an exact match for the address, with no intervening
148 // aliased stores.
149 Node* find_previous_store(PhaseValues* phase);
150
151 // Can this node (load or store) accurately see a stored value in
152 // the given memory state? (The state may or may not be in(Memory).)
153 Node* can_see_stored_value(Node* st, PhaseValues* phase) const;
154
155 void set_unaligned_access() { _unaligned_access = true; }
156 bool is_unaligned_access() const { return _unaligned_access; }
157 void set_mismatched_access() { _mismatched_access = true; }
158 bool is_mismatched_access() const { return _mismatched_access; }
159 void set_unsafe_access() { _unsafe_access = true; }
160 bool is_unsafe_access() const { return _unsafe_access; }
161
162 #ifndef PRODUCT
163 static void dump_adr_type(const Node* mem, const TypePtr* adr_type, outputStream *st);
164 virtual void dump_spec(outputStream *st) const;
165 #endif
166 };
167
168 //------------------------------LoadNode---------------------------------------
169 // Load value; requires Memory and Address
170 class LoadNode : public MemNode {
171 public:
172 // Some loads (from unsafe) should be pinned: they don't depend only
173 // on the dominating test. The field _control_dependency below records
174 // whether that node depends only on the dominating test.
175 // Pinned and UnknownControl are similar, but differ in that Pinned
176 // loads are not allowed to float across safepoints, whereas UnknownControl
177 // loads are allowed to do that. Therefore, Pinned is stricter.
178 enum ControlDependency {
179 Pinned,
180 UnknownControl,
181 DependsOnlyOnTest
182 };
183
184 private:
185 // LoadNode::hash() doesn't take the _control_dependency field
186 // into account: If the graph already has a non-pinned LoadNode and
187 // we add a pinned LoadNode with the same inputs, it's safe for GVN
188 // to replace the pinned LoadNode with the non-pinned LoadNode,
189 // otherwise it wouldn't be safe to have a non pinned LoadNode with
190 // those inputs in the first place. If the graph already has a
191 // pinned LoadNode and we add a non pinned LoadNode with the same
192 // inputs, it's safe (but suboptimal) for GVN to replace the
193 // non-pinned LoadNode by the pinned LoadNode.
194 ControlDependency _control_dependency;
195
196 // On platforms with weak memory ordering (e.g., PPC, Ia64) we distinguish
197 // loads that can be reordered, and such requiring acquire semantics to
198 // adhere to the Java specification. The required behaviour is stored in
199 // this field.
200 const MemOrd _mo;
201
202 AllocateNode* is_new_object_mark_load() const;
203
204 protected:
205 virtual bool cmp(const Node &n) const;
206 virtual uint size_of() const; // Size is bigger
207 // Should LoadNode::Ideal() attempt to remove control edges?
208 virtual bool can_remove_control() const;
209 const Type* const _type; // What kind of value is loaded?
210
211 virtual Node* find_previous_arraycopy(PhaseValues* phase, Node* ld_alloc, Node*& mem, bool can_see_stored_value) const;
212 public:
213
214 LoadNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const Type *rt, MemOrd mo, ControlDependency control_dependency)
215 : MemNode(c,mem,adr,at), _control_dependency(control_dependency), _mo(mo), _type(rt) {
216 init_class_id(Class_Load);
217 }
218 inline bool is_unordered() const { return !is_acquire(); }
219 inline bool is_acquire() const {
220 assert(_mo == unordered || _mo == acquire, "unexpected");
221 return _mo == acquire;
222 }
223 inline bool is_unsigned() const {
224 int lop = Opcode();
225 return (lop == Op_LoadUB) || (lop == Op_LoadUS);
226 }
227
228 // Polymorphic factory method:
229 static Node* make(PhaseGVN& gvn, Node* c, Node* mem, Node* adr,
230 const TypePtr* at, const Type* rt, BasicType bt,
231 MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest,
232 bool require_atomic_access = false, bool unaligned = false, bool mismatched = false, bool unsafe = false,
233 uint8_t barrier_data = 0);
234
235 virtual uint hash() const; // Check the type
236
237 // Handle algebraic identities here. If we have an identity, return the Node
238 // we are equivalent to. We look for Load of a Store.
239 virtual Node* Identity(PhaseGVN* phase);
240
241 // If the load is from Field memory and the pointer is non-null, it might be possible to
242 // zero out the control input.
243 // If the offset is constant and the base is an object allocation,
244 // try to hook me up to the exact initializing store.
245 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
246
247 // Return true if it's possible to split the Load through a Phi merging the bases
248 bool can_split_through_phi_base(PhaseGVN *phase);
249
250 // Split instance field load through Phi.
251 Node* split_through_phi(PhaseGVN *phase, bool ignore_missing_instance_id = false);
252
253 // Recover original value from boxed values
254 Node *eliminate_autobox(PhaseIterGVN *igvn);
255
256 // Compute a new Type for this node. Basically we just do the pre-check,
257 // then call the virtual add() to set the type.
258 virtual const Type* Value(PhaseGVN* phase) const;
259
260 // Common methods for LoadKlass and LoadNKlass nodes.
261 const Type* klass_value_common(PhaseGVN* phase) const;
262 Node* klass_identity_common(PhaseGVN* phase);
263
264 virtual uint ideal_reg() const;
265 virtual const Type *bottom_type() const;
266 // Following method is copied from TypeNode:
267 void set_type(const Type* t) {
268 assert(t != nullptr, "sanity");
269 debug_only(uint check_hash = (VerifyHashTableKeys && _hash_lock) ? hash() : NO_HASH);
270 *(const Type**)&_type = t; // cast away const-ness
271 // If this node is in the hash table, make sure it doesn't need a rehash.
272 assert(check_hash == NO_HASH || check_hash == hash(), "type change must preserve hash code");
273 }
274 const Type* type() const { assert(_type != nullptr, "sanity"); return _type; };
275
276 // Do not match memory edge
277 virtual uint match_edge(uint idx) const;
278
279 // Map a load opcode to its corresponding store opcode.
280 virtual int store_Opcode() const = 0;
281
282 // Check if the load's memory input is a Phi node with the same control.
283 bool is_instance_field_load_with_local_phi(Node* ctrl);
284
285 Node* convert_to_unsigned_load(PhaseGVN& gvn);
286 Node* convert_to_signed_load(PhaseGVN& gvn);
287
288 bool has_reinterpret_variant(const Type* rt);
289 Node* convert_to_reinterpret_load(PhaseGVN& gvn, const Type* rt);
290
291 ControlDependency control_dependency() const { return _control_dependency; }
292 bool has_unknown_control_dependency() const { return _control_dependency == UnknownControl; }
293 bool has_pinned_control_dependency() const { return _control_dependency == Pinned; }
294
295 #ifndef PRODUCT
296 virtual void dump_spec(outputStream *st) const;
297 #endif
298 #ifdef ASSERT
299 // Helper function to allow a raw load without control edge for some cases
300 static bool is_immutable_value(Node* adr);
301 #endif
302 protected:
303 const Type* load_array_final_field(const TypeKlassPtr *tkls,
304 ciKlass* klass) const;
305
306 Node* can_see_arraycopy_value(Node* st, PhaseGVN* phase) const;
307
308 // depends_only_on_test is almost always true, and needs to be almost always
309 // true to enable key hoisting & commoning optimizations. However, for the
310 // special case of RawPtr loads from TLS top & end, and other loads performed by
311 // GC barriers, the control edge carries the dependence preventing hoisting past
312 // a Safepoint instead of the memory edge. (An unfortunate consequence of having
313 // Safepoints not set Raw Memory; itself an unfortunate consequence of having Nodes
314 // which produce results (new raw memory state) inside of loops preventing all
315 // manner of other optimizations). Basically, it's ugly but so is the alternative.
316 // See comment in macro.cpp, around line 125 expand_allocate_common().
317 virtual bool depends_only_on_test() const {
318 return adr_type() != TypeRawPtr::BOTTOM && _control_dependency == DependsOnlyOnTest;
319 }
320 };
321
322 //------------------------------LoadBNode--------------------------------------
323 // Load a byte (8bits signed) from memory
324 class LoadBNode : public LoadNode {
325 public:
326 LoadBNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeInt *ti, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
327 : LoadNode(c, mem, adr, at, ti, mo, control_dependency) {}
328 virtual int Opcode() const;
329 virtual uint ideal_reg() const { return Op_RegI; }
330 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
331 virtual const Type* Value(PhaseGVN* phase) const;
332 virtual int store_Opcode() const { return Op_StoreB; }
333 virtual BasicType memory_type() const { return T_BYTE; }
334 };
335
336 //------------------------------LoadUBNode-------------------------------------
337 // Load a unsigned byte (8bits unsigned) from memory
338 class LoadUBNode : public LoadNode {
339 public:
340 LoadUBNode(Node* c, Node* mem, Node* adr, const TypePtr* at, const TypeInt* ti, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
341 : LoadNode(c, mem, adr, at, ti, mo, control_dependency) {}
342 virtual int Opcode() const;
343 virtual uint ideal_reg() const { return Op_RegI; }
344 virtual Node* Ideal(PhaseGVN *phase, bool can_reshape);
345 virtual const Type* Value(PhaseGVN* phase) const;
346 virtual int store_Opcode() const { return Op_StoreB; }
347 virtual BasicType memory_type() const { return T_BYTE; }
348 };
349
350 //------------------------------LoadUSNode-------------------------------------
351 // Load an unsigned short/char (16bits unsigned) from memory
352 class LoadUSNode : public LoadNode {
353 public:
354 LoadUSNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeInt *ti, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
355 : LoadNode(c, mem, adr, at, ti, mo, control_dependency) {}
356 virtual int Opcode() const;
357 virtual uint ideal_reg() const { return Op_RegI; }
358 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
359 virtual const Type* Value(PhaseGVN* phase) const;
360 virtual int store_Opcode() const { return Op_StoreC; }
361 virtual BasicType memory_type() const { return T_CHAR; }
362 };
363
364 //------------------------------LoadSNode--------------------------------------
365 // Load a short (16bits signed) from memory
366 class LoadSNode : public LoadNode {
367 public:
368 LoadSNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeInt *ti, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
369 : LoadNode(c, mem, adr, at, ti, mo, control_dependency) {}
370 virtual int Opcode() const;
371 virtual uint ideal_reg() const { return Op_RegI; }
372 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
373 virtual const Type* Value(PhaseGVN* phase) const;
374 virtual int store_Opcode() const { return Op_StoreC; }
375 virtual BasicType memory_type() const { return T_SHORT; }
376 };
377
378 //------------------------------LoadINode--------------------------------------
379 // Load an integer from memory
380 class LoadINode : public LoadNode {
381 public:
382 LoadINode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeInt *ti, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
383 : LoadNode(c, mem, adr, at, ti, mo, control_dependency) {}
384 virtual int Opcode() const;
385 virtual uint ideal_reg() const { return Op_RegI; }
386 virtual int store_Opcode() const { return Op_StoreI; }
387 virtual BasicType memory_type() const { return T_INT; }
388 };
389
390 //------------------------------LoadRangeNode----------------------------------
391 // Load an array length from the array
392 class LoadRangeNode : public LoadINode {
393 public:
394 LoadRangeNode(Node *c, Node *mem, Node *adr, const TypeInt *ti = TypeInt::POS)
395 : LoadINode(c, mem, adr, TypeAryPtr::RANGE, ti, MemNode::unordered) {}
396 virtual int Opcode() const;
397 virtual const Type* Value(PhaseGVN* phase) const;
398 virtual Node* Identity(PhaseGVN* phase);
399 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
400 };
401
402 //------------------------------LoadLNode--------------------------------------
403 // Load a long from memory
404 class LoadLNode : public LoadNode {
405 virtual uint hash() const { return LoadNode::hash() + _require_atomic_access; }
406 virtual bool cmp( const Node &n ) const {
407 return _require_atomic_access == ((LoadLNode&)n)._require_atomic_access
408 && LoadNode::cmp(n);
409 }
410 virtual uint size_of() const { return sizeof(*this); }
411 const bool _require_atomic_access; // is piecewise load forbidden?
412
413 public:
414 LoadLNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeLong *tl,
415 MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest, bool require_atomic_access = false)
416 : LoadNode(c, mem, adr, at, tl, mo, control_dependency), _require_atomic_access(require_atomic_access) {}
417 virtual int Opcode() const;
418 virtual uint ideal_reg() const { return Op_RegL; }
419 virtual int store_Opcode() const { return Op_StoreL; }
420 virtual BasicType memory_type() const { return T_LONG; }
421 bool require_atomic_access() const { return _require_atomic_access; }
422
423 #ifndef PRODUCT
424 virtual void dump_spec(outputStream *st) const {
425 LoadNode::dump_spec(st);
426 if (_require_atomic_access) st->print(" Atomic!");
427 }
428 #endif
429 };
430
431 //------------------------------LoadL_unalignedNode----------------------------
432 // Load a long from unaligned memory
433 class LoadL_unalignedNode : public LoadLNode {
434 public:
435 LoadL_unalignedNode(Node *c, Node *mem, Node *adr, const TypePtr* at, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
436 : LoadLNode(c, mem, adr, at, TypeLong::LONG, mo, control_dependency) {}
437 virtual int Opcode() const;
438 };
439
440 //------------------------------LoadFNode--------------------------------------
441 // Load a float (64 bits) from memory
442 class LoadFNode : public LoadNode {
443 public:
444 LoadFNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const Type *t, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
445 : LoadNode(c, mem, adr, at, t, mo, control_dependency) {}
446 virtual int Opcode() const;
447 virtual uint ideal_reg() const { return Op_RegF; }
448 virtual int store_Opcode() const { return Op_StoreF; }
449 virtual BasicType memory_type() const { return T_FLOAT; }
450 };
451
452 //------------------------------LoadDNode--------------------------------------
453 // Load a double (64 bits) from memory
454 class LoadDNode : public LoadNode {
455 virtual uint hash() const { return LoadNode::hash() + _require_atomic_access; }
456 virtual bool cmp( const Node &n ) const {
457 return _require_atomic_access == ((LoadDNode&)n)._require_atomic_access
458 && LoadNode::cmp(n);
459 }
460 virtual uint size_of() const { return sizeof(*this); }
461 const bool _require_atomic_access; // is piecewise load forbidden?
462
463 public:
464 LoadDNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const Type *t,
465 MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest, bool require_atomic_access = false)
466 : LoadNode(c, mem, adr, at, t, mo, control_dependency), _require_atomic_access(require_atomic_access) {}
467 virtual int Opcode() const;
468 virtual uint ideal_reg() const { return Op_RegD; }
469 virtual int store_Opcode() const { return Op_StoreD; }
470 virtual BasicType memory_type() const { return T_DOUBLE; }
471 bool require_atomic_access() const { return _require_atomic_access; }
472
473 #ifndef PRODUCT
474 virtual void dump_spec(outputStream *st) const {
475 LoadNode::dump_spec(st);
476 if (_require_atomic_access) st->print(" Atomic!");
477 }
478 #endif
479 };
480
481 //------------------------------LoadD_unalignedNode----------------------------
482 // Load a double from unaligned memory
483 class LoadD_unalignedNode : public LoadDNode {
484 public:
485 LoadD_unalignedNode(Node *c, Node *mem, Node *adr, const TypePtr* at, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
486 : LoadDNode(c, mem, adr, at, Type::DOUBLE, mo, control_dependency) {}
487 virtual int Opcode() const;
488 };
489
490 //------------------------------LoadPNode--------------------------------------
491 // Load a pointer from memory (either object or array)
492 class LoadPNode : public LoadNode {
493 public:
494 LoadPNode(Node *c, Node *mem, Node *adr, const TypePtr *at, const TypePtr* t, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
495 : LoadNode(c, mem, adr, at, t, mo, control_dependency) {}
496 virtual int Opcode() const;
497 virtual uint ideal_reg() const { return Op_RegP; }
498 virtual int store_Opcode() const { return Op_StoreP; }
499 virtual BasicType memory_type() const { return T_ADDRESS; }
500 };
501
502
503 //------------------------------LoadNNode--------------------------------------
504 // Load a narrow oop from memory (either object or array)
505 class LoadNNode : public LoadNode {
506 public:
507 LoadNNode(Node *c, Node *mem, Node *adr, const TypePtr *at, const Type* t, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
508 : LoadNode(c, mem, adr, at, t, mo, control_dependency) {}
509 virtual int Opcode() const;
510 virtual uint ideal_reg() const { return Op_RegN; }
511 virtual int store_Opcode() const { return Op_StoreN; }
512 virtual BasicType memory_type() const { return T_NARROWOOP; }
513 };
514
515 //------------------------------LoadKlassNode----------------------------------
516 // Load a Klass from an object
517 class LoadKlassNode : public LoadPNode {
518 protected:
519 // In most cases, LoadKlassNode does not have the control input set. If the control
520 // input is set, it must not be removed (by LoadNode::Ideal()).
521 virtual bool can_remove_control() const;
522 public:
523 LoadKlassNode(Node *c, Node *mem, Node *adr, const TypePtr *at, const TypeKlassPtr *tk, MemOrd mo)
524 : LoadPNode(c, mem, adr, at, tk, mo) {}
525 virtual int Opcode() const;
526 virtual const Type* Value(PhaseGVN* phase) const;
527 virtual Node* Identity(PhaseGVN* phase);
528 virtual bool depends_only_on_test() const { return true; }
529
530 // Polymorphic factory method:
531 static Node* make(PhaseGVN& gvn, Node* ctl, Node* mem, Node* adr, const TypePtr* at,
532 const TypeKlassPtr* tk = TypeInstKlassPtr::OBJECT);
533 };
534
535 //------------------------------LoadNKlassNode---------------------------------
536 // Load a narrow Klass from an object.
537 class LoadNKlassNode : public LoadNNode {
538 public:
539 LoadNKlassNode(Node *c, Node *mem, Node *adr, const TypePtr *at, const TypeNarrowKlass *tk, MemOrd mo)
540 : LoadNNode(c, mem, adr, at, tk, mo) {}
541 virtual int Opcode() const;
542 virtual uint ideal_reg() const { return Op_RegN; }
543 virtual int store_Opcode() const { return Op_StoreNKlass; }
544 virtual BasicType memory_type() const { return T_NARROWKLASS; }
545
546 virtual const Type* Value(PhaseGVN* phase) const;
547 virtual Node* Identity(PhaseGVN* phase);
548 virtual bool depends_only_on_test() const { return true; }
549 };
550
551
552 //------------------------------StoreNode--------------------------------------
553 // Store value; requires Store, Address and Value
554 class StoreNode : public MemNode {
555 private:
556 // On platforms with weak memory ordering (e.g., PPC, Ia64) we distinguish
557 // stores that can be reordered, and such requiring release semantics to
558 // adhere to the Java specification. The required behaviour is stored in
559 // this field.
560 const MemOrd _mo;
561 // Needed for proper cloning.
562 virtual uint size_of() const { return sizeof(*this); }
563 protected:
564 virtual bool cmp( const Node &n ) const;
565 virtual bool depends_only_on_test() const { return false; }
566
567 Node *Ideal_masked_input (PhaseGVN *phase, uint mask);
568 Node *Ideal_sign_extended_input(PhaseGVN *phase, int num_bits);
569
570 public:
571 // We must ensure that stores of object references will be visible
572 // only after the object's initialization. So the callers of this
573 // procedure must indicate that the store requires `release'
574 // semantics, if the stored value is an object reference that might
575 // point to a new object and may become externally visible.
576 StoreNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
577 : MemNode(c, mem, adr, at, val), _mo(mo) {
578 init_class_id(Class_Store);
579 }
580 StoreNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, Node *oop_store, MemOrd mo)
581 : MemNode(c, mem, adr, at, val, oop_store), _mo(mo) {
582 init_class_id(Class_Store);
583 }
584
585 inline bool is_unordered() const { return !is_release(); }
586 inline bool is_release() const {
587 assert((_mo == unordered || _mo == release), "unexpected");
588 return _mo == release;
589 }
590
591 // Conservatively release stores of object references in order to
592 // ensure visibility of object initialization.
593 static inline MemOrd release_if_reference(const BasicType t) {
594 #ifdef AARCH64
595 // AArch64 doesn't need a release store here because object
596 // initialization contains the necessary barriers.
597 return unordered;
598 #else
599 const MemOrd mo = (t == T_ARRAY ||
600 t == T_ADDRESS || // Might be the address of an object reference (`boxing').
601 t == T_OBJECT) ? release : unordered;
602 return mo;
603 #endif
604 }
605
606 // Polymorphic factory method
607 //
608 // We must ensure that stores of object references will be visible
609 // only after the object's initialization. So the callers of this
610 // procedure must indicate that the store requires `release'
611 // semantics, if the stored value is an object reference that might
612 // point to a new object and may become externally visible.
613 static StoreNode* make(PhaseGVN& gvn, Node* c, Node* mem, Node* adr,
614 const TypePtr* at, Node* val, BasicType bt,
615 MemOrd mo, bool require_atomic_access = false);
616
617 virtual uint hash() const; // Check the type
618
619 // If the store is to Field memory and the pointer is non-null, we can
620 // zero out the control input.
621 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
622
623 // Compute a new Type for this node. Basically we just do the pre-check,
624 // then call the virtual add() to set the type.
625 virtual const Type* Value(PhaseGVN* phase) const;
626
627 // Check for identity function on memory (Load then Store at same address)
628 virtual Node* Identity(PhaseGVN* phase);
629
630 // Do not match memory edge
631 virtual uint match_edge(uint idx) const;
632
633 virtual const Type *bottom_type() const; // returns Type::MEMORY
634
635 // Map a store opcode to its corresponding own opcode, trivially.
636 virtual int store_Opcode() const { return Opcode(); }
637
638 // have all possible loads of the value stored been optimized away?
639 bool value_never_loaded(PhaseValues* phase) const;
640
641 bool has_reinterpret_variant(const Type* vt);
642 Node* convert_to_reinterpret_store(PhaseGVN& gvn, Node* val, const Type* vt);
643
644 MemBarNode* trailing_membar() const;
645 };
646
647 //------------------------------StoreBNode-------------------------------------
648 // Store byte to memory
649 class StoreBNode : public StoreNode {
650 public:
651 StoreBNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
652 : StoreNode(c, mem, adr, at, val, mo) {}
653 virtual int Opcode() const;
654 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
655 virtual BasicType memory_type() const { return T_BYTE; }
656 };
657
658 //------------------------------StoreCNode-------------------------------------
659 // Store char/short to memory
660 class StoreCNode : public StoreNode {
661 public:
662 StoreCNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
663 : StoreNode(c, mem, adr, at, val, mo) {}
664 virtual int Opcode() const;
665 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
666 virtual BasicType memory_type() const { return T_CHAR; }
667 };
668
669 //------------------------------StoreINode-------------------------------------
670 // Store int to memory
671 class StoreINode : public StoreNode {
672 public:
673 StoreINode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
674 : StoreNode(c, mem, adr, at, val, mo) {}
675 virtual int Opcode() const;
676 virtual BasicType memory_type() const { return T_INT; }
677 };
678
679 //------------------------------StoreLNode-------------------------------------
680 // Store long to memory
681 class StoreLNode : public StoreNode {
682 virtual uint hash() const { return StoreNode::hash() + _require_atomic_access; }
683 virtual bool cmp( const Node &n ) const {
684 return _require_atomic_access == ((StoreLNode&)n)._require_atomic_access
685 && StoreNode::cmp(n);
686 }
687 virtual uint size_of() const { return sizeof(*this); }
688 const bool _require_atomic_access; // is piecewise store forbidden?
689
690 public:
691 StoreLNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo, bool require_atomic_access = false)
692 : StoreNode(c, mem, adr, at, val, mo), _require_atomic_access(require_atomic_access) {}
693 virtual int Opcode() const;
694 virtual BasicType memory_type() const { return T_LONG; }
695 bool require_atomic_access() const { return _require_atomic_access; }
696
697 #ifndef PRODUCT
698 virtual void dump_spec(outputStream *st) const {
699 StoreNode::dump_spec(st);
700 if (_require_atomic_access) st->print(" Atomic!");
701 }
702 #endif
703 };
704
705 //------------------------------StoreFNode-------------------------------------
706 // Store float to memory
707 class StoreFNode : public StoreNode {
708 public:
709 StoreFNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
710 : StoreNode(c, mem, adr, at, val, mo) {}
711 virtual int Opcode() const;
712 virtual BasicType memory_type() const { return T_FLOAT; }
713 };
714
715 //------------------------------StoreDNode-------------------------------------
716 // Store double to memory
717 class StoreDNode : public StoreNode {
718 virtual uint hash() const { return StoreNode::hash() + _require_atomic_access; }
719 virtual bool cmp( const Node &n ) const {
720 return _require_atomic_access == ((StoreDNode&)n)._require_atomic_access
721 && StoreNode::cmp(n);
722 }
723 virtual uint size_of() const { return sizeof(*this); }
724 const bool _require_atomic_access; // is piecewise store forbidden?
725 public:
726 StoreDNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val,
727 MemOrd mo, bool require_atomic_access = false)
728 : StoreNode(c, mem, adr, at, val, mo), _require_atomic_access(require_atomic_access) {}
729 virtual int Opcode() const;
730 virtual BasicType memory_type() const { return T_DOUBLE; }
731 bool require_atomic_access() const { return _require_atomic_access; }
732
733 #ifndef PRODUCT
734 virtual void dump_spec(outputStream *st) const {
735 StoreNode::dump_spec(st);
736 if (_require_atomic_access) st->print(" Atomic!");
737 }
738 #endif
739
740 };
741
742 //------------------------------StorePNode-------------------------------------
743 // Store pointer to memory
744 class StorePNode : public StoreNode {
745 public:
746 StorePNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
747 : StoreNode(c, mem, adr, at, val, mo) {}
748 virtual int Opcode() const;
749 virtual BasicType memory_type() const { return T_ADDRESS; }
750 };
751
752 //------------------------------StoreNNode-------------------------------------
753 // Store narrow oop to memory
754 class StoreNNode : public StoreNode {
755 public:
756 StoreNNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
757 : StoreNode(c, mem, adr, at, val, mo) {}
758 virtual int Opcode() const;
759 virtual BasicType memory_type() const { return T_NARROWOOP; }
760 };
761
762 //------------------------------StoreNKlassNode--------------------------------------
763 // Store narrow klass to memory
764 class StoreNKlassNode : public StoreNNode {
765 public:
766 StoreNKlassNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
767 : StoreNNode(c, mem, adr, at, val, mo) {}
768 virtual int Opcode() const;
769 virtual BasicType memory_type() const { return T_NARROWKLASS; }
770 };
771
772 //------------------------------StoreCMNode-----------------------------------
773 // Store card-mark byte to memory for CM
774 // The last StoreCM before a SafePoint must be preserved and occur after its "oop" store
775 // Preceding equivalent StoreCMs may be eliminated.
776 class StoreCMNode : public StoreNode {
777 private:
778 virtual uint hash() const { return StoreNode::hash() + _oop_alias_idx; }
779 virtual bool cmp( const Node &n ) const {
780 return _oop_alias_idx == ((StoreCMNode&)n)._oop_alias_idx
781 && StoreNode::cmp(n);
782 }
783 virtual uint size_of() const { return sizeof(*this); }
784 int _oop_alias_idx; // The alias_idx of OopStore
785
786 public:
787 StoreCMNode( Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, Node *oop_store, int oop_alias_idx ) :
788 StoreNode(c, mem, adr, at, val, oop_store, MemNode::release),
789 _oop_alias_idx(oop_alias_idx) {
790 assert(_oop_alias_idx >= Compile::AliasIdxRaw ||
791 _oop_alias_idx == Compile::AliasIdxBot && !Compile::current()->do_aliasing(),
792 "bad oop alias idx");
793 }
794 virtual int Opcode() const;
795 virtual Node* Identity(PhaseGVN* phase);
796 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
797 virtual const Type* Value(PhaseGVN* phase) const;
798 virtual BasicType memory_type() const { return T_VOID; } // unspecific
799 int oop_alias_idx() const { return _oop_alias_idx; }
800 };
801
802 //------------------------------SCMemProjNode---------------------------------------
803 // This class defines a projection of the memory state of a store conditional node.
804 // These nodes return a value, but also update memory.
805 class SCMemProjNode : public ProjNode {
806 public:
807 enum {SCMEMPROJCON = (uint)-2};
808 SCMemProjNode( Node *src) : ProjNode( src, SCMEMPROJCON) { }
809 virtual int Opcode() const;
810 virtual bool is_CFG() const { return false; }
811 virtual const Type *bottom_type() const {return Type::MEMORY;}
812 virtual const TypePtr *adr_type() const {
813 Node* ctrl = in(0);
814 if (ctrl == nullptr) return nullptr; // node is dead
815 return ctrl->in(MemNode::Memory)->adr_type();
816 }
817 virtual uint ideal_reg() const { return 0;} // memory projections don't have a register
818 virtual const Type* Value(PhaseGVN* phase) const;
819 #ifndef PRODUCT
820 virtual void dump_spec(outputStream *st) const {};
821 #endif
822 };
823
824 //------------------------------LoadStoreNode---------------------------
825 // Note: is_Mem() method returns 'true' for this class.
826 class LoadStoreNode : public Node {
827 private:
828 const Type* const _type; // What kind of value is loaded?
829 const TypePtr* _adr_type; // What kind of memory is being addressed?
830 uint8_t _barrier_data; // Bit field with barrier information
831 virtual uint size_of() const; // Size is bigger
832 public:
833 LoadStoreNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at, const Type* rt, uint required );
834 virtual bool depends_only_on_test() const { return false; }
835 virtual uint match_edge(uint idx) const { return idx == MemNode::Address || idx == MemNode::ValueIn; }
836
837 virtual const Type *bottom_type() const { return _type; }
838 virtual uint ideal_reg() const;
839 virtual const class TypePtr *adr_type() const { return _adr_type; } // returns bottom_type of address
840 virtual const Type* Value(PhaseGVN* phase) const;
841
842 bool result_not_used() const;
843 MemBarNode* trailing_membar() const;
844
845 uint8_t barrier_data() { return _barrier_data; }
846 void set_barrier_data(uint8_t barrier_data) { _barrier_data = barrier_data; }
847 };
848
849 class LoadStoreConditionalNode : public LoadStoreNode {
850 public:
851 enum {
852 ExpectedIn = MemNode::ValueIn+1 // One more input than MemNode
853 };
854 LoadStoreConditionalNode(Node *c, Node *mem, Node *adr, Node *val, Node *ex);
855 virtual const Type* Value(PhaseGVN* phase) const;
856 };
857
858 class CompareAndSwapNode : public LoadStoreConditionalNode {
859 private:
860 const MemNode::MemOrd _mem_ord;
861 public:
862 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) {}
863 MemNode::MemOrd order() const {
864 return _mem_ord;
865 }
866 virtual uint size_of() const { return sizeof(*this); }
867 };
868
869 class CompareAndExchangeNode : public LoadStoreNode {
870 private:
871 const MemNode::MemOrd _mem_ord;
872 public:
873 enum {
874 ExpectedIn = MemNode::ValueIn+1 // One more input than MemNode
875 };
876 CompareAndExchangeNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord, const TypePtr* at, const Type* t) :
877 LoadStoreNode(c, mem, adr, val, at, t, 5), _mem_ord(mem_ord) {
878 init_req(ExpectedIn, ex );
879 }
880
881 MemNode::MemOrd order() const {
882 return _mem_ord;
883 }
884 virtual uint size_of() const { return sizeof(*this); }
885 };
886
887 //------------------------------CompareAndSwapBNode---------------------------
888 class CompareAndSwapBNode : public CompareAndSwapNode {
889 public:
890 CompareAndSwapBNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
891 virtual int Opcode() const;
892 };
893
894 //------------------------------CompareAndSwapSNode---------------------------
895 class CompareAndSwapSNode : public CompareAndSwapNode {
896 public:
897 CompareAndSwapSNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
898 virtual int Opcode() const;
899 };
900
901 //------------------------------CompareAndSwapINode---------------------------
902 class CompareAndSwapINode : public CompareAndSwapNode {
903 public:
904 CompareAndSwapINode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
905 virtual int Opcode() const;
906 };
907
908 //------------------------------CompareAndSwapLNode---------------------------
909 class CompareAndSwapLNode : public CompareAndSwapNode {
910 public:
911 CompareAndSwapLNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
912 virtual int Opcode() const;
913 };
914
915 //------------------------------CompareAndSwapPNode---------------------------
916 class CompareAndSwapPNode : public CompareAndSwapNode {
917 public:
918 CompareAndSwapPNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
919 virtual int Opcode() const;
920 };
921
922 //------------------------------CompareAndSwapNNode---------------------------
923 class CompareAndSwapNNode : public CompareAndSwapNode {
924 public:
925 CompareAndSwapNNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
926 virtual int Opcode() const;
927 };
928
929 //------------------------------WeakCompareAndSwapBNode---------------------------
930 class WeakCompareAndSwapBNode : public CompareAndSwapNode {
931 public:
932 WeakCompareAndSwapBNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
933 virtual int Opcode() const;
934 };
935
936 //------------------------------WeakCompareAndSwapSNode---------------------------
937 class WeakCompareAndSwapSNode : public CompareAndSwapNode {
938 public:
939 WeakCompareAndSwapSNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
940 virtual int Opcode() const;
941 };
942
943 //------------------------------WeakCompareAndSwapINode---------------------------
944 class WeakCompareAndSwapINode : public CompareAndSwapNode {
945 public:
946 WeakCompareAndSwapINode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
947 virtual int Opcode() const;
948 };
949
950 //------------------------------WeakCompareAndSwapLNode---------------------------
951 class WeakCompareAndSwapLNode : public CompareAndSwapNode {
952 public:
953 WeakCompareAndSwapLNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
954 virtual int Opcode() const;
955 };
956
957 //------------------------------WeakCompareAndSwapPNode---------------------------
958 class WeakCompareAndSwapPNode : public CompareAndSwapNode {
959 public:
960 WeakCompareAndSwapPNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
961 virtual int Opcode() const;
962 };
963
964 //------------------------------WeakCompareAndSwapNNode---------------------------
965 class WeakCompareAndSwapNNode : public CompareAndSwapNode {
966 public:
967 WeakCompareAndSwapNNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
968 virtual int Opcode() const;
969 };
970
971 //------------------------------CompareAndExchangeBNode---------------------------
972 class CompareAndExchangeBNode : public CompareAndExchangeNode {
973 public:
974 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) { }
975 virtual int Opcode() const;
976 };
977
978
979 //------------------------------CompareAndExchangeSNode---------------------------
980 class CompareAndExchangeSNode : public CompareAndExchangeNode {
981 public:
982 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) { }
983 virtual int Opcode() const;
984 };
985
986 //------------------------------CompareAndExchangeLNode---------------------------
987 class CompareAndExchangeLNode : public CompareAndExchangeNode {
988 public:
989 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) { }
990 virtual int Opcode() const;
991 };
992
993
994 //------------------------------CompareAndExchangeINode---------------------------
995 class CompareAndExchangeINode : public CompareAndExchangeNode {
996 public:
997 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) { }
998 virtual int Opcode() const;
999 };
1000
1001
1002 //------------------------------CompareAndExchangePNode---------------------------
1003 class CompareAndExchangePNode : public CompareAndExchangeNode {
1004 public:
1005 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) { }
1006 virtual int Opcode() const;
1007 };
1008
1009 //------------------------------CompareAndExchangeNNode---------------------------
1010 class CompareAndExchangeNNode : public CompareAndExchangeNode {
1011 public:
1012 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) { }
1013 virtual int Opcode() const;
1014 };
1015
1016 //------------------------------GetAndAddBNode---------------------------
1017 class GetAndAddBNode : public LoadStoreNode {
1018 public:
1019 GetAndAddBNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeInt::BYTE, 4) { }
1020 virtual int Opcode() const;
1021 };
1022
1023 //------------------------------GetAndAddSNode---------------------------
1024 class GetAndAddSNode : public LoadStoreNode {
1025 public:
1026 GetAndAddSNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeInt::SHORT, 4) { }
1027 virtual int Opcode() const;
1028 };
1029
1030 //------------------------------GetAndAddINode---------------------------
1031 class GetAndAddINode : public LoadStoreNode {
1032 public:
1033 GetAndAddINode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeInt::INT, 4) { }
1034 virtual int Opcode() const;
1035 };
1036
1037 //------------------------------GetAndAddLNode---------------------------
1038 class GetAndAddLNode : public LoadStoreNode {
1039 public:
1040 GetAndAddLNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeLong::LONG, 4) { }
1041 virtual int Opcode() const;
1042 };
1043
1044 //------------------------------GetAndSetBNode---------------------------
1045 class GetAndSetBNode : public LoadStoreNode {
1046 public:
1047 GetAndSetBNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeInt::BYTE, 4) { }
1048 virtual int Opcode() const;
1049 };
1050
1051 //------------------------------GetAndSetSNode---------------------------
1052 class GetAndSetSNode : public LoadStoreNode {
1053 public:
1054 GetAndSetSNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeInt::SHORT, 4) { }
1055 virtual int Opcode() const;
1056 };
1057
1058 //------------------------------GetAndSetINode---------------------------
1059 class GetAndSetINode : public LoadStoreNode {
1060 public:
1061 GetAndSetINode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeInt::INT, 4) { }
1062 virtual int Opcode() const;
1063 };
1064
1065 //------------------------------GetAndSetLNode---------------------------
1066 class GetAndSetLNode : public LoadStoreNode {
1067 public:
1068 GetAndSetLNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeLong::LONG, 4) { }
1069 virtual int Opcode() const;
1070 };
1071
1072 //------------------------------GetAndSetPNode---------------------------
1073 class GetAndSetPNode : public LoadStoreNode {
1074 public:
1075 GetAndSetPNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at, const Type* t ) : LoadStoreNode(c, mem, adr, val, at, t, 4) { }
1076 virtual int Opcode() const;
1077 };
1078
1079 //------------------------------GetAndSetNNode---------------------------
1080 class GetAndSetNNode : public LoadStoreNode {
1081 public:
1082 GetAndSetNNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at, const Type* t ) : LoadStoreNode(c, mem, adr, val, at, t, 4) { }
1083 virtual int Opcode() const;
1084 };
1085
1086 //------------------------------ClearArray-------------------------------------
1087 class ClearArrayNode: public Node {
1088 private:
1089 bool _is_large;
1090 public:
1091 ClearArrayNode( Node *ctrl, Node *arymem, Node *word_cnt, Node *base, bool is_large)
1092 : Node(ctrl,arymem,word_cnt,base), _is_large(is_large) {
1093 init_class_id(Class_ClearArray);
1094 }
1095 virtual int Opcode() const;
1096 virtual const Type *bottom_type() const { return Type::MEMORY; }
1097 // ClearArray modifies array elements, and so affects only the
1098 // array memory addressed by the bottom_type of its base address.
1099 virtual const class TypePtr *adr_type() const;
1100 virtual Node* Identity(PhaseGVN* phase);
1101 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
1102 virtual uint match_edge(uint idx) const;
1103 bool is_large() const { return _is_large; }
1104
1105 // Clear the given area of an object or array.
1106 // The start offset must always be aligned mod BytesPerInt.
1107 // The end offset must always be aligned mod BytesPerLong.
1108 // Return the new memory.
1109 static Node* clear_memory(Node* control, Node* mem, Node* dest,
1110 intptr_t start_offset,
1111 intptr_t end_offset,
1112 PhaseGVN* phase);
1113 static Node* clear_memory(Node* control, Node* mem, Node* dest,
1114 intptr_t start_offset,
1115 Node* end_offset,
1116 PhaseGVN* phase);
1117 static Node* clear_memory(Node* control, Node* mem, Node* dest,
1118 Node* start_offset,
1119 Node* end_offset,
1120 PhaseGVN* phase);
1121 // Return allocation input memory edge if it is different instance
1122 // or itself if it is the one we are looking for.
1123 static bool step_through(Node** np, uint instance_id, PhaseValues* phase);
1124 };
1125
1126 //------------------------------MemBar-----------------------------------------
1127 // There are different flavors of Memory Barriers to match the Java Memory
1128 // Model. Monitor-enter and volatile-load act as Acquires: no following ref
1129 // can be moved to before them. We insert a MemBar-Acquire after a FastLock or
1130 // volatile-load. Monitor-exit and volatile-store act as Release: no
1131 // preceding ref can be moved to after them. We insert a MemBar-Release
1132 // before a FastUnlock or volatile-store. All volatiles need to be
1133 // serialized, so we follow all volatile-stores with a MemBar-Volatile to
1134 // separate it from any following volatile-load.
1135 class MemBarNode: public MultiNode {
1136 virtual uint hash() const ; // { return NO_HASH; }
1137 virtual bool cmp( const Node &n ) const ; // Always fail, except on self
1138
1139 virtual uint size_of() const { return sizeof(*this); }
1140 // Memory type this node is serializing. Usually either rawptr or bottom.
1141 const TypePtr* _adr_type;
1142
1143 // How is this membar related to a nearby memory access?
1144 enum {
1145 Standalone,
1146 TrailingLoad,
1147 TrailingStore,
1148 LeadingStore,
1149 TrailingLoadStore,
1150 LeadingLoadStore,
1151 TrailingPartialArrayCopy
1152 } _kind;
1153
1154 #ifdef ASSERT
1155 uint _pair_idx;
1156 #endif
1157
1158 public:
1159 enum {
1160 Precedent = TypeFunc::Parms // optional edge to force precedence
1161 };
1162 MemBarNode(Compile* C, int alias_idx, Node* precedent);
1163 virtual int Opcode() const = 0;
1164 virtual const class TypePtr *adr_type() const { return _adr_type; }
1165 virtual const Type* Value(PhaseGVN* phase) const;
1166 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
1167 virtual uint match_edge(uint idx) const { return 0; }
1168 virtual const Type *bottom_type() const { return TypeTuple::MEMBAR; }
1169 virtual Node *match( const ProjNode *proj, const Matcher *m );
1170 // Factory method. Builds a wide or narrow membar.
1171 // Optional 'precedent' becomes an extra edge if not null.
1172 static MemBarNode* make(Compile* C, int opcode,
1173 int alias_idx = Compile::AliasIdxBot,
1174 Node* precedent = nullptr);
1175
1176 MemBarNode* trailing_membar() const;
1177 MemBarNode* leading_membar() const;
1178
1179 void set_trailing_load() { _kind = TrailingLoad; }
1180 bool trailing_load() const { return _kind == TrailingLoad; }
1181 bool trailing_store() const { return _kind == TrailingStore; }
1182 bool leading_store() const { return _kind == LeadingStore; }
1183 bool trailing_load_store() const { return _kind == TrailingLoadStore; }
1184 bool leading_load_store() const { return _kind == LeadingLoadStore; }
1185 bool trailing() const { return _kind == TrailingLoad || _kind == TrailingStore || _kind == TrailingLoadStore; }
1186 bool leading() const { return _kind == LeadingStore || _kind == LeadingLoadStore; }
1187 bool standalone() const { return _kind == Standalone; }
1188 void set_trailing_partial_array_copy() { _kind = TrailingPartialArrayCopy; }
1189 bool trailing_partial_array_copy() const { return _kind == TrailingPartialArrayCopy; }
1190
1191 static void set_store_pair(MemBarNode* leading, MemBarNode* trailing);
1192 static void set_load_store_pair(MemBarNode* leading, MemBarNode* trailing);
1193
1194 void remove(PhaseIterGVN *igvn);
1195 };
1196
1197 // "Acquire" - no following ref can move before (but earlier refs can
1198 // follow, like an early Load stalled in cache). Requires multi-cpu
1199 // visibility. Inserted after a volatile load.
1200 class MemBarAcquireNode: public MemBarNode {
1201 public:
1202 MemBarAcquireNode(Compile* C, int alias_idx, Node* precedent)
1203 : MemBarNode(C, alias_idx, precedent) {}
1204 virtual int Opcode() const;
1205 };
1206
1207 // "Acquire" - no following ref can move before (but earlier refs can
1208 // follow, like an early Load stalled in cache). Requires multi-cpu
1209 // visibility. Inserted independent of any load, as required
1210 // for intrinsic Unsafe.loadFence().
1211 class LoadFenceNode: public MemBarNode {
1212 public:
1213 LoadFenceNode(Compile* C, int alias_idx, Node* precedent)
1214 : MemBarNode(C, alias_idx, precedent) {}
1215 virtual int Opcode() const;
1216 };
1217
1218 // "Release" - no earlier ref can move after (but later refs can move
1219 // up, like a speculative pipelined cache-hitting Load). Requires
1220 // multi-cpu visibility. Inserted before a volatile store.
1221 class MemBarReleaseNode: public MemBarNode {
1222 public:
1223 MemBarReleaseNode(Compile* C, int alias_idx, Node* precedent)
1224 : MemBarNode(C, alias_idx, precedent) {}
1225 virtual int Opcode() const;
1226 };
1227
1228 // "Release" - no earlier ref can move after (but later refs can move
1229 // up, like a speculative pipelined cache-hitting Load). Requires
1230 // multi-cpu visibility. Inserted independent of any store, as required
1231 // for intrinsic Unsafe.storeFence().
1232 class StoreFenceNode: public MemBarNode {
1233 public:
1234 StoreFenceNode(Compile* C, int alias_idx, Node* precedent)
1235 : MemBarNode(C, alias_idx, precedent) {}
1236 virtual int Opcode() const;
1237 };
1238
1239 // "Acquire" - no following ref can move before (but earlier refs can
1240 // follow, like an early Load stalled in cache). Requires multi-cpu
1241 // visibility. Inserted after a FastLock.
1242 class MemBarAcquireLockNode: public MemBarNode {
1243 public:
1244 MemBarAcquireLockNode(Compile* C, int alias_idx, Node* precedent)
1245 : MemBarNode(C, alias_idx, precedent) {}
1246 virtual int Opcode() const;
1247 };
1248
1249 // "Release" - no earlier ref can move after (but later refs can move
1250 // up, like a speculative pipelined cache-hitting Load). Requires
1251 // multi-cpu visibility. Inserted before a FastUnLock.
1252 class MemBarReleaseLockNode: public MemBarNode {
1253 public:
1254 MemBarReleaseLockNode(Compile* C, int alias_idx, Node* precedent)
1255 : MemBarNode(C, alias_idx, precedent) {}
1256 virtual int Opcode() const;
1257 };
1258
1259 class MemBarStoreStoreNode: public MemBarNode {
1260 public:
1261 MemBarStoreStoreNode(Compile* C, int alias_idx, Node* precedent)
1262 : MemBarNode(C, alias_idx, precedent) {
1263 init_class_id(Class_MemBarStoreStore);
1264 }
1265 virtual int Opcode() const;
1266 };
1267
1268 class StoreStoreFenceNode: public MemBarNode {
1269 public:
1270 StoreStoreFenceNode(Compile* C, int alias_idx, Node* precedent)
1271 : MemBarNode(C, alias_idx, precedent) {}
1272 virtual int Opcode() const;
1273 };
1274
1275 // Ordering between a volatile store and a following volatile load.
1276 // Requires multi-CPU visibility?
1277 class MemBarVolatileNode: public MemBarNode {
1278 public:
1279 MemBarVolatileNode(Compile* C, int alias_idx, Node* precedent)
1280 : MemBarNode(C, alias_idx, precedent) {}
1281 virtual int Opcode() const;
1282 };
1283
1284 // Ordering within the same CPU. Used to order unsafe memory references
1285 // inside the compiler when we lack alias info. Not needed "outside" the
1286 // compiler because the CPU does all the ordering for us.
1287 class MemBarCPUOrderNode: public MemBarNode {
1288 public:
1289 MemBarCPUOrderNode(Compile* C, int alias_idx, Node* precedent)
1290 : MemBarNode(C, alias_idx, precedent) {}
1291 virtual int Opcode() const;
1292 virtual uint ideal_reg() const { return 0; } // not matched in the AD file
1293 };
1294
1295 class OnSpinWaitNode: public MemBarNode {
1296 public:
1297 OnSpinWaitNode(Compile* C, int alias_idx, Node* precedent)
1298 : MemBarNode(C, alias_idx, precedent) {}
1299 virtual int Opcode() const;
1300 };
1301
1302 // Isolation of object setup after an AllocateNode and before next safepoint.
1303 // (See comment in memnode.cpp near InitializeNode::InitializeNode for semantics.)
1304 class InitializeNode: public MemBarNode {
1305 friend class AllocateNode;
1306
1307 enum {
1308 Incomplete = 0,
1309 Complete = 1,
1310 WithArraycopy = 2
1311 };
1312 int _is_complete;
1313
1314 bool _does_not_escape;
1315
1316 public:
1317 enum {
1318 Control = TypeFunc::Control,
1319 Memory = TypeFunc::Memory, // MergeMem for states affected by this op
1320 RawAddress = TypeFunc::Parms+0, // the newly-allocated raw address
1321 RawStores = TypeFunc::Parms+1 // zero or more stores (or TOP)
1322 };
1323
1324 InitializeNode(Compile* C, int adr_type, Node* rawoop);
1325 virtual int Opcode() const;
1326 virtual uint size_of() const { return sizeof(*this); }
1327 virtual uint ideal_reg() const { return 0; } // not matched in the AD file
1328 virtual const RegMask &in_RegMask(uint) const; // mask for RawAddress
1329
1330 // Manage incoming memory edges via a MergeMem on in(Memory):
1331 Node* memory(uint alias_idx);
1332
1333 // The raw memory edge coming directly from the Allocation.
1334 // The contents of this memory are *always* all-zero-bits.
1335 Node* zero_memory() { return memory(Compile::AliasIdxRaw); }
1336
1337 // Return the corresponding allocation for this initialization (or null if none).
1338 // (Note: Both InitializeNode::allocation and AllocateNode::initialization
1339 // are defined in graphKit.cpp, which sets up the bidirectional relation.)
1340 AllocateNode* allocation();
1341
1342 // Anything other than zeroing in this init?
1343 bool is_non_zero();
1344
1345 // An InitializeNode must completed before macro expansion is done.
1346 // Completion requires that the AllocateNode must be followed by
1347 // initialization of the new memory to zero, then to any initializers.
1348 bool is_complete() { return _is_complete != Incomplete; }
1349 bool is_complete_with_arraycopy() { return (_is_complete & WithArraycopy) != 0; }
1350
1351 // Mark complete. (Must not yet be complete.)
1352 void set_complete(PhaseGVN* phase);
1353 void set_complete_with_arraycopy() { _is_complete = Complete | WithArraycopy; }
1354
1355 bool does_not_escape() { return _does_not_escape; }
1356 void set_does_not_escape() { _does_not_escape = true; }
1357
1358 #ifdef ASSERT
1359 // ensure all non-degenerate stores are ordered and non-overlapping
1360 bool stores_are_sane(PhaseValues* phase);
1361 #endif //ASSERT
1362
1363 // See if this store can be captured; return offset where it initializes.
1364 // Return 0 if the store cannot be moved (any sort of problem).
1365 intptr_t can_capture_store(StoreNode* st, PhaseGVN* phase, bool can_reshape);
1366
1367 // Capture another store; reformat it to write my internal raw memory.
1368 // Return the captured copy, else null if there is some sort of problem.
1369 Node* capture_store(StoreNode* st, intptr_t start, PhaseGVN* phase, bool can_reshape);
1370
1371 // Find captured store which corresponds to the range [start..start+size).
1372 // Return my own memory projection (meaning the initial zero bits)
1373 // if there is no such store. Return null if there is a problem.
1374 Node* find_captured_store(intptr_t start, int size_in_bytes, PhaseValues* phase);
1375
1376 // Called when the associated AllocateNode is expanded into CFG.
1377 Node* complete_stores(Node* rawctl, Node* rawmem, Node* rawptr,
1378 intptr_t header_size, Node* size_in_bytes,
1379 PhaseIterGVN* phase);
1380
1381 private:
1382 void remove_extra_zeroes();
1383
1384 // Find out where a captured store should be placed (or already is placed).
1385 int captured_store_insertion_point(intptr_t start, int size_in_bytes,
1386 PhaseValues* phase);
1387
1388 static intptr_t get_store_offset(Node* st, PhaseValues* phase);
1389
1390 Node* make_raw_address(intptr_t offset, PhaseGVN* phase);
1391
1392 bool detect_init_independence(Node* value, PhaseGVN* phase);
1393
1394 void coalesce_subword_stores(intptr_t header_size, Node* size_in_bytes,
1395 PhaseGVN* phase);
1396
1397 intptr_t find_next_fullword_store(uint i, PhaseGVN* phase);
1398 };
1399
1400 //------------------------------MergeMem---------------------------------------
1401 // (See comment in memnode.cpp near MergeMemNode::MergeMemNode for semantics.)
1402 class MergeMemNode: public Node {
1403 virtual uint hash() const ; // { return NO_HASH; }
1404 virtual bool cmp( const Node &n ) const ; // Always fail, except on self
1405 friend class MergeMemStream;
1406 MergeMemNode(Node* def); // clients use MergeMemNode::make
1407
1408 public:
1409 // If the input is a whole memory state, clone it with all its slices intact.
1410 // Otherwise, make a new memory state with just that base memory input.
1411 // In either case, the result is a newly created MergeMem.
1412 static MergeMemNode* make(Node* base_memory);
1413
1414 virtual int Opcode() const;
1415 virtual Node* Identity(PhaseGVN* phase);
1416 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
1417 virtual uint ideal_reg() const { return NotAMachineReg; }
1418 virtual uint match_edge(uint idx) const { return 0; }
1419 virtual const RegMask &out_RegMask() const;
1420 virtual const Type *bottom_type() const { return Type::MEMORY; }
1421 virtual const TypePtr *adr_type() const { return TypePtr::BOTTOM; }
1422 // sparse accessors
1423 // Fetch the previously stored "set_memory_at", or else the base memory.
1424 // (Caller should clone it if it is a phi-nest.)
1425 Node* memory_at(uint alias_idx) const;
1426 // set the memory, regardless of its previous value
1427 void set_memory_at(uint alias_idx, Node* n);
1428 // the "base" is the memory that provides the non-finite support
1429 Node* base_memory() const { return in(Compile::AliasIdxBot); }
1430 // warning: setting the base can implicitly set any of the other slices too
1431 void set_base_memory(Node* def);
1432 // sentinel value which denotes a copy of the base memory:
1433 Node* empty_memory() const { return in(Compile::AliasIdxTop); }
1434 static Node* make_empty_memory(); // where the sentinel comes from
1435 bool is_empty_memory(Node* n) const { assert((n == empty_memory()) == n->is_top(), "sanity"); return n->is_top(); }
1436 // hook for the iterator, to perform any necessary setup
1437 void iteration_setup(const MergeMemNode* other = nullptr);
1438 // push sentinels until I am at least as long as the other (semantic no-op)
1439 void grow_to_match(const MergeMemNode* other);
1440 bool verify_sparse() const PRODUCT_RETURN0;
1441 #ifndef PRODUCT
1442 virtual void dump_spec(outputStream *st) const;
1443 #endif
1444 };
1445
1446 class MergeMemStream : public StackObj {
1447 private:
1448 MergeMemNode* _mm;
1449 const MergeMemNode* _mm2; // optional second guy, contributes non-empty iterations
1450 Node* _mm_base; // loop-invariant base memory of _mm
1451 int _idx;
1452 int _cnt;
1453 Node* _mem;
1454 Node* _mem2;
1455 int _cnt2;
1456
1457 void init(MergeMemNode* mm, const MergeMemNode* mm2 = nullptr) {
1458 // subsume_node will break sparseness at times, whenever a memory slice
1459 // folds down to a copy of the base ("fat") memory. In such a case,
1460 // the raw edge will update to base, although it should be top.
1461 // This iterator will recognize either top or base_memory as an
1462 // "empty" slice. See is_empty, is_empty2, and next below.
1463 //
1464 // The sparseness property is repaired in MergeMemNode::Ideal.
1465 // As long as access to a MergeMem goes through this iterator
1466 // or the memory_at accessor, flaws in the sparseness will
1467 // never be observed.
1468 //
1469 // Also, iteration_setup repairs sparseness.
1470 assert(mm->verify_sparse(), "please, no dups of base");
1471 assert(mm2==nullptr || mm2->verify_sparse(), "please, no dups of base");
1472
1473 _mm = mm;
1474 _mm_base = mm->base_memory();
1475 _mm2 = mm2;
1476 _cnt = mm->req();
1477 _idx = Compile::AliasIdxBot-1; // start at the base memory
1478 _mem = nullptr;
1479 _mem2 = nullptr;
1480 }
1481
1482 #ifdef ASSERT
1483 Node* check_memory() const {
1484 if (at_base_memory())
1485 return _mm->base_memory();
1486 else if ((uint)_idx < _mm->req() && !_mm->in(_idx)->is_top())
1487 return _mm->memory_at(_idx);
1488 else
1489 return _mm_base;
1490 }
1491 Node* check_memory2() const {
1492 return at_base_memory()? _mm2->base_memory(): _mm2->memory_at(_idx);
1493 }
1494 #endif
1495
1496 static bool match_memory(Node* mem, const MergeMemNode* mm, int idx) PRODUCT_RETURN0;
1497 void assert_synch() const {
1498 assert(!_mem || _idx >= _cnt || match_memory(_mem, _mm, _idx),
1499 "no side-effects except through the stream");
1500 }
1501
1502 public:
1503
1504 // expected usages:
1505 // for (MergeMemStream mms(mem->is_MergeMem()); next_non_empty(); ) { ... }
1506 // for (MergeMemStream mms(mem1, mem2); next_non_empty2(); ) { ... }
1507
1508 // iterate over one merge
1509 MergeMemStream(MergeMemNode* mm) {
1510 mm->iteration_setup();
1511 init(mm);
1512 debug_only(_cnt2 = 999);
1513 }
1514 // iterate in parallel over two merges
1515 // only iterates through non-empty elements of mm2
1516 MergeMemStream(MergeMemNode* mm, const MergeMemNode* mm2) {
1517 assert(mm2, "second argument must be a MergeMem also");
1518 ((MergeMemNode*)mm2)->iteration_setup(); // update hidden state
1519 mm->iteration_setup(mm2);
1520 init(mm, mm2);
1521 _cnt2 = mm2->req();
1522 }
1523 #ifdef ASSERT
1524 ~MergeMemStream() {
1525 assert_synch();
1526 }
1527 #endif
1528
1529 MergeMemNode* all_memory() const {
1530 return _mm;
1531 }
1532 Node* base_memory() const {
1533 assert(_mm_base == _mm->base_memory(), "no update to base memory, please");
1534 return _mm_base;
1535 }
1536 const MergeMemNode* all_memory2() const {
1537 assert(_mm2 != nullptr, "");
1538 return _mm2;
1539 }
1540 bool at_base_memory() const {
1541 return _idx == Compile::AliasIdxBot;
1542 }
1543 int alias_idx() const {
1544 assert(_mem, "must call next 1st");
1545 return _idx;
1546 }
1547
1548 const TypePtr* adr_type() const {
1549 return Compile::current()->get_adr_type(alias_idx());
1550 }
1551
1552 const TypePtr* adr_type(Compile* C) const {
1553 return C->get_adr_type(alias_idx());
1554 }
1555 bool is_empty() const {
1556 assert(_mem, "must call next 1st");
1557 assert(_mem->is_top() == (_mem==_mm->empty_memory()), "correct sentinel");
1558 return _mem->is_top();
1559 }
1560 bool is_empty2() const {
1561 assert(_mem2, "must call next 1st");
1562 assert(_mem2->is_top() == (_mem2==_mm2->empty_memory()), "correct sentinel");
1563 return _mem2->is_top();
1564 }
1565 Node* memory() const {
1566 assert(!is_empty(), "must not be empty");
1567 assert_synch();
1568 return _mem;
1569 }
1570 // get the current memory, regardless of empty or non-empty status
1571 Node* force_memory() const {
1572 assert(!is_empty() || !at_base_memory(), "");
1573 // Use _mm_base to defend against updates to _mem->base_memory().
1574 Node *mem = _mem->is_top() ? _mm_base : _mem;
1575 assert(mem == check_memory(), "");
1576 return mem;
1577 }
1578 Node* memory2() const {
1579 assert(_mem2 == check_memory2(), "");
1580 return _mem2;
1581 }
1582 void set_memory(Node* mem) {
1583 if (at_base_memory()) {
1584 // Note that this does not change the invariant _mm_base.
1585 _mm->set_base_memory(mem);
1586 } else {
1587 _mm->set_memory_at(_idx, mem);
1588 }
1589 _mem = mem;
1590 assert_synch();
1591 }
1592
1593 // Recover from a side effect to the MergeMemNode.
1594 void set_memory() {
1595 _mem = _mm->in(_idx);
1596 }
1597
1598 bool next() { return next(false); }
1599 bool next2() { return next(true); }
1600
1601 bool next_non_empty() { return next_non_empty(false); }
1602 bool next_non_empty2() { return next_non_empty(true); }
1603 // next_non_empty2 can yield states where is_empty() is true
1604
1605 private:
1606 // find the next item, which might be empty
1607 bool next(bool have_mm2) {
1608 assert((_mm2 != nullptr) == have_mm2, "use other next");
1609 assert_synch();
1610 if (++_idx < _cnt) {
1611 // Note: This iterator allows _mm to be non-sparse.
1612 // It behaves the same whether _mem is top or base_memory.
1613 _mem = _mm->in(_idx);
1614 if (have_mm2)
1615 _mem2 = _mm2->in((_idx < _cnt2) ? _idx : Compile::AliasIdxTop);
1616 return true;
1617 }
1618 return false;
1619 }
1620
1621 // find the next non-empty item
1622 bool next_non_empty(bool have_mm2) {
1623 while (next(have_mm2)) {
1624 if (!is_empty()) {
1625 // make sure _mem2 is filled in sensibly
1626 if (have_mm2 && _mem2->is_top()) _mem2 = _mm2->base_memory();
1627 return true;
1628 } else if (have_mm2 && !is_empty2()) {
1629 return true; // is_empty() == true
1630 }
1631 }
1632 return false;
1633 }
1634 };
1635
1636 // cachewb node for guaranteeing writeback of the cache line at a
1637 // given address to (non-volatile) RAM
1638 class CacheWBNode : public Node {
1639 public:
1640 CacheWBNode(Node *ctrl, Node *mem, Node *addr) : Node(ctrl, mem, addr) {}
1641 virtual int Opcode() const;
1642 virtual uint ideal_reg() const { return NotAMachineReg; }
1643 virtual uint match_edge(uint idx) const { return (idx == 2); }
1644 virtual const TypePtr *adr_type() const { return TypePtr::BOTTOM; }
1645 virtual const Type *bottom_type() const { return Type::MEMORY; }
1646 };
1647
1648 // cachewb pre sync node for ensuring that writebacks are serialised
1649 // relative to preceding or following stores
1650 class CacheWBPreSyncNode : public Node {
1651 public:
1652 CacheWBPreSyncNode(Node *ctrl, Node *mem) : Node(ctrl, mem) {}
1653 virtual int Opcode() const;
1654 virtual uint ideal_reg() const { return NotAMachineReg; }
1655 virtual uint match_edge(uint idx) const { return false; }
1656 virtual const TypePtr *adr_type() const { return TypePtr::BOTTOM; }
1657 virtual const Type *bottom_type() const { return Type::MEMORY; }
1658 };
1659
1660 // cachewb pre sync node for ensuring that writebacks are serialised
1661 // relative to preceding or following stores
1662 class CacheWBPostSyncNode : public Node {
1663 public:
1664 CacheWBPostSyncNode(Node *ctrl, Node *mem) : Node(ctrl, mem) {}
1665 virtual int Opcode() const;
1666 virtual uint ideal_reg() const { return NotAMachineReg; }
1667 virtual uint match_edge(uint idx) const { return false; }
1668 virtual const TypePtr *adr_type() const { return TypePtr::BOTTOM; }
1669 virtual const Type *bottom_type() const { return Type::MEMORY; }
1670 };
1671
1672 //------------------------------Prefetch---------------------------------------
1673
1674 // Allocation prefetch which may fault, TLAB size have to be adjusted.
1675 class PrefetchAllocationNode : public Node {
1676 public:
1677 PrefetchAllocationNode(Node *mem, Node *adr) : Node(0,mem,adr) {}
1678 virtual int Opcode() const;
1679 virtual uint ideal_reg() const { return NotAMachineReg; }
1680 virtual uint match_edge(uint idx) const { return idx==2; }
1681 virtual const Type *bottom_type() const { return ( AllocatePrefetchStyle == 3 ) ? Type::MEMORY : Type::ABIO; }
1682 };
1683
1684 #endif // SHARE_OPTO_MEMNODE_HPP