1 /*
2 * Copyright (c) 1997, 2015, 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
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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
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24
25 #ifndef SHARE_VM_OPTO_MEMNODE_HPP
26 #define SHARE_VM_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 protected:
43 #ifdef ASSERT
44 const TypePtr* _adr_type; // What kind of memory is being addressed?
45 #endif
46 virtual uint size_of() const; // Size is bigger (ASSERT only)
47 public:
48 enum { Control, // When is it safe to do this load?
49 Memory, // Chunk of memory is being loaded from
50 Address, // Actually address, derived from base
51 ValueIn, // Value to store
52 OopStore // Preceeding oop store, only in StoreCM
53 };
54 typedef enum { unordered = 0,
55 acquire, // Load has to acquire or be succeeded by MemBarAcquire.
56 release // Store has to release or be preceded by MemBarRelease.
57 } MemOrd;
58 protected:
59 MemNode( Node *c0, Node *c1, Node *c2, const TypePtr* at )
60 : Node(c0,c1,c2 ) {
61 init_class_id(Class_Mem);
62 debug_only(_adr_type=at; adr_type();)
63 }
64 MemNode( Node *c0, Node *c1, Node *c2, const TypePtr* at, Node *c3 )
65 : Node(c0,c1,c2,c3) {
66 init_class_id(Class_Mem);
67 debug_only(_adr_type=at; adr_type();)
68 }
69 MemNode( Node *c0, Node *c1, Node *c2, const TypePtr* at, Node *c3, Node *c4)
70 : Node(c0,c1,c2,c3,c4) {
71 init_class_id(Class_Mem);
72 debug_only(_adr_type=at; adr_type();)
73 }
74
75 public:
76 // Helpers for the optimizer. Documented in memnode.cpp.
77 static bool detect_ptr_independence(Node* p1, AllocateNode* a1,
78 Node* p2, AllocateNode* a2,
79 PhaseTransform* phase);
80 static bool adr_phi_is_loop_invariant(Node* adr_phi, Node* cast);
81
82 static Node *optimize_simple_memory_chain(Node *mchain, const TypeOopPtr *t_oop, Node *load, PhaseGVN *phase);
83 static Node *optimize_memory_chain(Node *mchain, const TypePtr *t_adr, Node *load, PhaseGVN *phase);
84 // This one should probably be a phase-specific function:
85 static bool all_controls_dominate(Node* dom, Node* sub);
86
87 // Find any cast-away of null-ness and keep its control.
88 static Node *Ideal_common_DU_postCCP( PhaseCCP *ccp, Node* n, Node* adr );
89 virtual Node *Ideal_DU_postCCP( PhaseCCP *ccp );
90
91 virtual const class TypePtr *adr_type() const; // returns bottom_type of address
92
93 // Shared code for Ideal methods:
94 Node *Ideal_common(PhaseGVN *phase, bool can_reshape); // Return -1 for short-circuit NULL.
95
96 // Helper function for adr_type() implementations.
97 static const TypePtr* calculate_adr_type(const Type* t, const TypePtr* cross_check = NULL);
98
99 // Raw access function, to allow copying of adr_type efficiently in
100 // product builds and retain the debug info for debug builds.
101 const TypePtr *raw_adr_type() const {
102 #ifdef ASSERT
103 return _adr_type;
104 #else
105 return 0;
106 #endif
107 }
108
109 // Map a load or store opcode to its corresponding store opcode.
110 // (Return -1 if unknown.)
111 virtual int store_Opcode() const { return -1; }
112
113 // What is the type of the value in memory? (T_VOID mean "unspecified".)
114 virtual BasicType memory_type() const = 0;
115 virtual int memory_size() const {
116 #ifdef ASSERT
117 return type2aelembytes(memory_type(), true);
118 #else
119 return type2aelembytes(memory_type());
120 #endif
121 }
122
123 // Search through memory states which precede this node (load or store).
124 // Look for an exact match for the address, with no intervening
125 // aliased stores.
126 Node* find_previous_store(PhaseTransform* phase);
127
128 // Can this node (load or store) accurately see a stored value in
129 // the given memory state? (The state may or may not be in(Memory).)
130 Node* can_see_stored_value(Node* st, PhaseTransform* phase) const;
131
132 #ifndef PRODUCT
133 static void dump_adr_type(const Node* mem, const TypePtr* adr_type, outputStream *st);
134 virtual void dump_spec(outputStream *st) const;
135 #endif
136 };
137
138 //------------------------------LoadNode---------------------------------------
139 // Load value; requires Memory and Address
140 class LoadNode : public MemNode {
141 private:
142 // On platforms with weak memory ordering (e.g., PPC, Ia64) we distinguish
143 // loads that can be reordered, and such requiring acquire semantics to
144 // adhere to the Java specification. The required behaviour is stored in
145 // this field.
146 const MemOrd _mo;
147
148 protected:
149 virtual uint cmp(const Node &n) const;
150 virtual uint size_of() const; // Size is bigger
151 // Should LoadNode::Ideal() attempt to remove control edges?
152 virtual bool can_remove_control() const;
153 const Type* const _type; // What kind of value is loaded?
154 public:
155
156 LoadNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const Type *rt, MemOrd mo)
157 : MemNode(c,mem,adr,at), _type(rt), _mo(mo) {
158 init_class_id(Class_Load);
159 }
160 inline bool is_unordered() const { return !is_acquire(); }
161 inline bool is_acquire() const {
162 assert(_mo == unordered || _mo == acquire, "unexpected");
163 return _mo == acquire;
164 }
165
166 // Polymorphic factory method:
167 static Node* make(PhaseGVN& gvn, Node *c, Node *mem, Node *adr,
168 const TypePtr* at, const Type *rt, BasicType bt, MemOrd mo);
169
170 virtual uint hash() const; // Check the type
171
172 // Handle algebraic identities here. If we have an identity, return the Node
173 // we are equivalent to. We look for Load of a Store.
174 virtual Node *Identity( PhaseTransform *phase );
175
176 // If the load is from Field memory and the pointer is non-null, it might be possible to
177 // zero out the control input.
178 // If the offset is constant and the base is an object allocation,
179 // try to hook me up to the exact initializing store.
180 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
181
182 // Split instance field load through Phi.
183 Node* split_through_phi(PhaseGVN *phase);
184
185 // Recover original value from boxed values
186 Node *eliminate_autobox(PhaseGVN *phase);
187
188 // Compute a new Type for this node. Basically we just do the pre-check,
189 // then call the virtual add() to set the type.
190 virtual const Type *Value( PhaseTransform *phase ) const;
191
192 // Common methods for LoadKlass and LoadNKlass nodes.
193 const Type *klass_value_common( PhaseTransform *phase ) const;
194 Node *klass_identity_common( PhaseTransform *phase );
195
196 virtual uint ideal_reg() const;
197 virtual const Type *bottom_type() const;
198 // Following method is copied from TypeNode:
199 void set_type(const Type* t) {
200 assert(t != NULL, "sanity");
201 debug_only(uint check_hash = (VerifyHashTableKeys && _hash_lock) ? hash() : NO_HASH);
202 *(const Type**)&_type = t; // cast away const-ness
203 // If this node is in the hash table, make sure it doesn't need a rehash.
204 assert(check_hash == NO_HASH || check_hash == hash(), "type change must preserve hash code");
205 }
206 const Type* type() const { assert(_type != NULL, "sanity"); return _type; };
207
208 // Do not match memory edge
209 virtual uint match_edge(uint idx) const;
210
211 // Map a load opcode to its corresponding store opcode.
212 virtual int store_Opcode() const = 0;
213
214 // Check if the load's memory input is a Phi node with the same control.
215 bool is_instance_field_load_with_local_phi(Node* ctrl);
216
217 #ifndef PRODUCT
218 virtual void dump_spec(outputStream *st) const;
219 #endif
220 #ifdef ASSERT
221 // Helper function to allow a raw load without control edge for some cases
222 static bool is_immutable_value(Node* adr);
223 #endif
224 protected:
225 const Type* load_array_final_field(const TypeKlassPtr *tkls,
226 ciKlass* klass) const;
227 // depends_only_on_test is almost always true, and needs to be almost always
228 // true to enable key hoisting & commoning optimizations. However, for the
229 // special case of RawPtr loads from TLS top & end, and other loads performed by
230 // GC barriers, the control edge carries the dependence preventing hoisting past
231 // a Safepoint instead of the memory edge. (An unfortunate consequence of having
232 // Safepoints not set Raw Memory; itself an unfortunate consequence of having Nodes
233 // which produce results (new raw memory state) inside of loops preventing all
234 // manner of other optimizations). Basically, it's ugly but so is the alternative.
235 // See comment in macro.cpp, around line 125 expand_allocate_common().
236 virtual bool depends_only_on_test() const { return adr_type() != TypeRawPtr::BOTTOM; }
237
238 };
239
240 //------------------------------LoadBNode--------------------------------------
241 // Load a byte (8bits signed) from memory
242 class LoadBNode : public LoadNode {
243 public:
244 LoadBNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeInt *ti, MemOrd mo)
245 : LoadNode(c, mem, adr, at, ti, mo) {}
246 virtual int Opcode() const;
247 virtual uint ideal_reg() const { return Op_RegI; }
248 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
249 virtual const Type *Value(PhaseTransform *phase) const;
250 virtual int store_Opcode() const { return Op_StoreB; }
251 virtual BasicType memory_type() const { return T_BYTE; }
252 };
253
254 //------------------------------LoadUBNode-------------------------------------
255 // Load a unsigned byte (8bits unsigned) from memory
256 class LoadUBNode : public LoadNode {
257 public:
258 LoadUBNode(Node* c, Node* mem, Node* adr, const TypePtr* at, const TypeInt* ti, MemOrd mo)
259 : LoadNode(c, mem, adr, at, ti, mo) {}
260 virtual int Opcode() const;
261 virtual uint ideal_reg() const { return Op_RegI; }
262 virtual Node* Ideal(PhaseGVN *phase, bool can_reshape);
263 virtual const Type *Value(PhaseTransform *phase) const;
264 virtual int store_Opcode() const { return Op_StoreB; }
265 virtual BasicType memory_type() const { return T_BYTE; }
266 };
267
268 //------------------------------LoadUSNode-------------------------------------
269 // Load an unsigned short/char (16bits unsigned) from memory
270 class LoadUSNode : public LoadNode {
271 public:
272 LoadUSNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeInt *ti, MemOrd mo)
273 : LoadNode(c, mem, adr, at, ti, mo) {}
274 virtual int Opcode() const;
275 virtual uint ideal_reg() const { return Op_RegI; }
276 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
277 virtual const Type *Value(PhaseTransform *phase) const;
278 virtual int store_Opcode() const { return Op_StoreC; }
279 virtual BasicType memory_type() const { return T_CHAR; }
280 };
281
282 //------------------------------LoadSNode--------------------------------------
283 // Load a short (16bits signed) from memory
284 class LoadSNode : public LoadNode {
285 public:
286 LoadSNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeInt *ti, MemOrd mo)
287 : LoadNode(c, mem, adr, at, ti, mo) {}
288 virtual int Opcode() const;
289 virtual uint ideal_reg() const { return Op_RegI; }
290 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
291 virtual const Type *Value(PhaseTransform *phase) const;
292 virtual int store_Opcode() const { return Op_StoreC; }
293 virtual BasicType memory_type() const { return T_SHORT; }
294 };
295
296 //------------------------------LoadINode--------------------------------------
297 // Load an integer from memory
298 class LoadINode : public LoadNode {
299 public:
300 LoadINode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeInt *ti, MemOrd mo)
301 : LoadNode(c, mem, adr, at, ti, mo) {}
302 virtual int Opcode() const;
303 virtual uint ideal_reg() const { return Op_RegI; }
304 virtual int store_Opcode() const { return Op_StoreI; }
305 virtual BasicType memory_type() const { return T_INT; }
306 };
307
308 //------------------------------LoadRangeNode----------------------------------
309 // Load an array length from the array
310 class LoadRangeNode : public LoadINode {
311 public:
312 LoadRangeNode(Node *c, Node *mem, Node *adr, const TypeInt *ti = TypeInt::POS)
313 : LoadINode(c, mem, adr, TypeAryPtr::RANGE, ti, MemNode::unordered) {}
314 virtual int Opcode() const;
315 virtual const Type *Value( PhaseTransform *phase ) const;
316 virtual Node *Identity( PhaseTransform *phase );
317 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
318 };
319
320 //------------------------------LoadLNode--------------------------------------
321 // Load a long from memory
322 class LoadLNode : public LoadNode {
323 virtual uint hash() const { return LoadNode::hash() + _require_atomic_access; }
324 virtual uint cmp( const Node &n ) const {
325 return _require_atomic_access == ((LoadLNode&)n)._require_atomic_access
326 && LoadNode::cmp(n);
327 }
328 virtual uint size_of() const { return sizeof(*this); }
329 const bool _require_atomic_access; // is piecewise load forbidden?
330
331 public:
332 LoadLNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeLong *tl,
333 MemOrd mo, bool require_atomic_access = false)
334 : LoadNode(c, mem, adr, at, tl, mo), _require_atomic_access(require_atomic_access) {}
335 virtual int Opcode() const;
336 virtual uint ideal_reg() const { return Op_RegL; }
337 virtual int store_Opcode() const { return Op_StoreL; }
338 virtual BasicType memory_type() const { return T_LONG; }
339 bool require_atomic_access() const { return _require_atomic_access; }
340 static LoadLNode* make_atomic(Node* ctl, Node* mem, Node* adr, const TypePtr* adr_type,
341 const Type* rt, MemOrd mo);
342 #ifndef PRODUCT
343 virtual void dump_spec(outputStream *st) const {
344 LoadNode::dump_spec(st);
345 if (_require_atomic_access) st->print(" Atomic!");
346 }
347 #endif
348 };
349
350 //------------------------------LoadL_unalignedNode----------------------------
351 // Load a long from unaligned memory
352 class LoadL_unalignedNode : public LoadLNode {
353 public:
354 LoadL_unalignedNode(Node *c, Node *mem, Node *adr, const TypePtr* at, MemOrd mo)
355 : LoadLNode(c, mem, adr, at, TypeLong::LONG, mo) {}
356 virtual int Opcode() const;
357 };
358
359 //------------------------------LoadFNode--------------------------------------
360 // Load a float (64 bits) from memory
361 class LoadFNode : public LoadNode {
362 public:
363 LoadFNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const Type *t, MemOrd mo)
364 : LoadNode(c, mem, adr, at, t, mo) {}
365 virtual int Opcode() const;
366 virtual uint ideal_reg() const { return Op_RegF; }
367 virtual int store_Opcode() const { return Op_StoreF; }
368 virtual BasicType memory_type() const { return T_FLOAT; }
369 };
370
371 //------------------------------LoadDNode--------------------------------------
372 // Load a double (64 bits) from memory
373 class LoadDNode : public LoadNode {
374 virtual uint hash() const { return LoadNode::hash() + _require_atomic_access; }
375 virtual uint cmp( const Node &n ) const {
376 return _require_atomic_access == ((LoadDNode&)n)._require_atomic_access
377 && LoadNode::cmp(n);
378 }
379 virtual uint size_of() const { return sizeof(*this); }
380 const bool _require_atomic_access; // is piecewise load forbidden?
381
382 public:
383 LoadDNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const Type *t,
384 MemOrd mo, bool require_atomic_access = false)
385 : LoadNode(c, mem, adr, at, t, mo), _require_atomic_access(require_atomic_access) {}
386 virtual int Opcode() const;
387 virtual uint ideal_reg() const { return Op_RegD; }
388 virtual int store_Opcode() const { return Op_StoreD; }
389 virtual BasicType memory_type() const { return T_DOUBLE; }
390 bool require_atomic_access() const { return _require_atomic_access; }
391 static LoadDNode* make_atomic(Node* ctl, Node* mem, Node* adr, const TypePtr* adr_type,
392 const Type* rt, MemOrd mo);
393 #ifndef PRODUCT
394 virtual void dump_spec(outputStream *st) const {
395 LoadNode::dump_spec(st);
396 if (_require_atomic_access) st->print(" Atomic!");
397 }
398 #endif
399 };
400
401 //------------------------------LoadD_unalignedNode----------------------------
402 // Load a double from unaligned memory
403 class LoadD_unalignedNode : public LoadDNode {
404 public:
405 LoadD_unalignedNode(Node *c, Node *mem, Node *adr, const TypePtr* at, MemOrd mo)
406 : LoadDNode(c, mem, adr, at, Type::DOUBLE, mo) {}
407 virtual int Opcode() const;
408 };
409
410 //------------------------------LoadPNode--------------------------------------
411 // Load a pointer from memory (either object or array)
412 class LoadPNode : public LoadNode {
413 public:
414 LoadPNode(Node *c, Node *mem, Node *adr, const TypePtr *at, const TypePtr* t, MemOrd mo)
415 : LoadNode(c, mem, adr, at, t, mo) {}
416 virtual int Opcode() const;
417 virtual uint ideal_reg() const { return Op_RegP; }
418 virtual int store_Opcode() const { return Op_StoreP; }
419 virtual BasicType memory_type() const { return T_ADDRESS; }
420 };
421
422
423 //------------------------------LoadNNode--------------------------------------
424 // Load a narrow oop from memory (either object or array)
425 class LoadNNode : public LoadNode {
426 public:
427 LoadNNode(Node *c, Node *mem, Node *adr, const TypePtr *at, const Type* t, MemOrd mo)
428 : LoadNode(c, mem, adr, at, t, mo) {}
429 virtual int Opcode() const;
430 virtual uint ideal_reg() const { return Op_RegN; }
431 virtual int store_Opcode() const { return Op_StoreN; }
432 virtual BasicType memory_type() const { return T_NARROWOOP; }
433 };
434
435 //------------------------------LoadKlassNode----------------------------------
436 // Load a Klass from an object
437 class LoadKlassNode : public LoadPNode {
438 protected:
439 // In most cases, LoadKlassNode does not have the control input set. If the control
440 // input is set, it must not be removed (by LoadNode::Ideal()).
441 virtual bool can_remove_control() const;
442 public:
443 LoadKlassNode(Node *c, Node *mem, Node *adr, const TypePtr *at, const TypeKlassPtr *tk, MemOrd mo)
444 : LoadPNode(c, mem, adr, at, tk, mo) {}
445 virtual int Opcode() const;
446 virtual const Type *Value( PhaseTransform *phase ) const;
447 virtual Node *Identity( PhaseTransform *phase );
448 virtual bool depends_only_on_test() const { return true; }
449
450 // Polymorphic factory method:
451 static Node* make(PhaseGVN& gvn, Node* ctl, Node* mem, Node* adr, const TypePtr* at,
452 const TypeKlassPtr* tk = TypeKlassPtr::OBJECT);
453 };
454
455 //------------------------------LoadNKlassNode---------------------------------
456 // Load a narrow Klass from an object.
457 class LoadNKlassNode : public LoadNNode {
458 public:
459 LoadNKlassNode(Node *c, Node *mem, Node *adr, const TypePtr *at, const TypeNarrowKlass *tk, MemOrd mo)
460 : LoadNNode(c, mem, adr, at, tk, mo) {}
461 virtual int Opcode() const;
462 virtual uint ideal_reg() const { return Op_RegN; }
463 virtual int store_Opcode() const { return Op_StoreNKlass; }
464 virtual BasicType memory_type() const { return T_NARROWKLASS; }
465
466 virtual const Type *Value( PhaseTransform *phase ) const;
467 virtual Node *Identity( PhaseTransform *phase );
468 virtual bool depends_only_on_test() const { return true; }
469 };
470
471
472 //------------------------------StoreNode--------------------------------------
473 // Store value; requires Store, Address and Value
474 class StoreNode : public MemNode {
475 private:
476 // On platforms with weak memory ordering (e.g., PPC, Ia64) we distinguish
477 // stores that can be reordered, and such requiring release semantics to
478 // adhere to the Java specification. The required behaviour is stored in
479 // this field.
480 const MemOrd _mo;
481 // Needed for proper cloning.
482 virtual uint size_of() const { return sizeof(*this); }
483 protected:
484 virtual uint cmp( const Node &n ) const;
485 virtual bool depends_only_on_test() const { return false; }
486
487 Node *Ideal_masked_input (PhaseGVN *phase, uint mask);
488 Node *Ideal_sign_extended_input(PhaseGVN *phase, int num_bits);
489
490 public:
491 // We must ensure that stores of object references will be visible
492 // only after the object's initialization. So the callers of this
493 // procedure must indicate that the store requires `release'
494 // semantics, if the stored value is an object reference that might
495 // point to a new object and may become externally visible.
496 StoreNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
497 : MemNode(c, mem, adr, at, val), _mo(mo) {
498 init_class_id(Class_Store);
499 }
500 StoreNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, Node *oop_store, MemOrd mo)
501 : MemNode(c, mem, adr, at, val, oop_store), _mo(mo) {
502 init_class_id(Class_Store);
503 }
504
505 inline bool is_unordered() const { return !is_release(); }
506 inline bool is_release() const {
507 assert((_mo == unordered || _mo == release), "unexpected");
508 return _mo == release;
509 }
510
511 // Conservatively release stores of object references in order to
512 // ensure visibility of object initialization.
513 static inline MemOrd release_if_reference(const BasicType t) {
514 #ifdef AARCH64
515 // AArch64 doesn't need a release store here because object
516 // initialization contains the necessary barriers.
517 return unordered;
518 #else
519 const MemOrd mo = (t == T_ARRAY ||
520 t == T_ADDRESS || // Might be the address of an object reference (`boxing').
521 t == T_OBJECT) ? release : unordered;
522 return mo;
523 #endif
524 }
525
526 // Polymorphic factory method
527 //
528 // We must ensure that stores of object references will be visible
529 // only after the object's initialization. So the callers of this
530 // procedure must indicate that the store requires `release'
531 // semantics, if the stored value is an object reference that might
532 // point to a new object and may become externally visible.
533 static StoreNode* make(PhaseGVN& gvn, Node *c, Node *mem, Node *adr,
534 const TypePtr* at, Node *val, BasicType bt, MemOrd mo);
535
536 virtual uint hash() const; // Check the type
537
538 // If the store is to Field memory and the pointer is non-null, we can
539 // zero out the control input.
540 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
541
542 // Compute a new Type for this node. Basically we just do the pre-check,
543 // then call the virtual add() to set the type.
544 virtual const Type *Value( PhaseTransform *phase ) const;
545
546 // Check for identity function on memory (Load then Store at same address)
547 virtual Node *Identity( PhaseTransform *phase );
548
549 // Do not match memory edge
550 virtual uint match_edge(uint idx) const;
551
552 virtual const Type *bottom_type() const; // returns Type::MEMORY
553
554 // Map a store opcode to its corresponding own opcode, trivially.
555 virtual int store_Opcode() const { return Opcode(); }
556
557 // have all possible loads of the value stored been optimized away?
558 bool value_never_loaded(PhaseTransform *phase) const;
559 };
560
561 //------------------------------StoreBNode-------------------------------------
562 // Store byte to memory
563 class StoreBNode : public StoreNode {
564 public:
565 StoreBNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
566 : StoreNode(c, mem, adr, at, val, mo) {}
567 virtual int Opcode() const;
568 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
569 virtual BasicType memory_type() const { return T_BYTE; }
570 };
571
572 //------------------------------StoreCNode-------------------------------------
573 // Store char/short to memory
574 class StoreCNode : public StoreNode {
575 public:
576 StoreCNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
577 : StoreNode(c, mem, adr, at, val, mo) {}
578 virtual int Opcode() const;
579 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
580 virtual BasicType memory_type() const { return T_CHAR; }
581 };
582
583 //------------------------------StoreINode-------------------------------------
584 // Store int to memory
585 class StoreINode : public StoreNode {
586 public:
587 StoreINode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
588 : StoreNode(c, mem, adr, at, val, mo) {}
589 virtual int Opcode() const;
590 virtual BasicType memory_type() const { return T_INT; }
591 };
592
593 //------------------------------StoreLNode-------------------------------------
594 // Store long to memory
595 class StoreLNode : public StoreNode {
596 virtual uint hash() const { return StoreNode::hash() + _require_atomic_access; }
597 virtual uint cmp( const Node &n ) const {
598 return _require_atomic_access == ((StoreLNode&)n)._require_atomic_access
599 && StoreNode::cmp(n);
600 }
601 virtual uint size_of() const { return sizeof(*this); }
602 const bool _require_atomic_access; // is piecewise store forbidden?
603
604 public:
605 StoreLNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo, bool require_atomic_access = false)
606 : StoreNode(c, mem, adr, at, val, mo), _require_atomic_access(require_atomic_access) {}
607 virtual int Opcode() const;
608 virtual BasicType memory_type() const { return T_LONG; }
609 bool require_atomic_access() const { return _require_atomic_access; }
610 static StoreLNode* make_atomic(Node* ctl, Node* mem, Node* adr, const TypePtr* adr_type, Node* val, MemOrd mo);
611 #ifndef PRODUCT
612 virtual void dump_spec(outputStream *st) const {
613 StoreNode::dump_spec(st);
614 if (_require_atomic_access) st->print(" Atomic!");
615 }
616 #endif
617 };
618
619 //------------------------------StoreFNode-------------------------------------
620 // Store float to memory
621 class StoreFNode : public StoreNode {
622 public:
623 StoreFNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
624 : StoreNode(c, mem, adr, at, val, mo) {}
625 virtual int Opcode() const;
626 virtual BasicType memory_type() const { return T_FLOAT; }
627 };
628
629 //------------------------------StoreDNode-------------------------------------
630 // Store double to memory
631 class StoreDNode : public StoreNode {
632 virtual uint hash() const { return StoreNode::hash() + _require_atomic_access; }
633 virtual uint cmp( const Node &n ) const {
634 return _require_atomic_access == ((StoreDNode&)n)._require_atomic_access
635 && StoreNode::cmp(n);
636 }
637 virtual uint size_of() const { return sizeof(*this); }
638 const bool _require_atomic_access; // is piecewise store forbidden?
639 public:
640 StoreDNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val,
641 MemOrd mo, bool require_atomic_access = false)
642 : StoreNode(c, mem, adr, at, val, mo), _require_atomic_access(require_atomic_access) {}
643 virtual int Opcode() const;
644 virtual BasicType memory_type() const { return T_DOUBLE; }
645 bool require_atomic_access() const { return _require_atomic_access; }
646 static StoreDNode* make_atomic(Node* ctl, Node* mem, Node* adr, const TypePtr* adr_type, Node* val, MemOrd mo);
647 #ifndef PRODUCT
648 virtual void dump_spec(outputStream *st) const {
649 StoreNode::dump_spec(st);
650 if (_require_atomic_access) st->print(" Atomic!");
651 }
652 #endif
653
654 };
655
656 //------------------------------StorePNode-------------------------------------
657 // Store pointer to memory
658 class StorePNode : public StoreNode {
659 public:
660 StorePNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
661 : StoreNode(c, mem, adr, at, val, mo) {}
662 virtual int Opcode() const;
663 virtual BasicType memory_type() const { return T_ADDRESS; }
664 };
665
666 //------------------------------StoreNNode-------------------------------------
667 // Store narrow oop to memory
668 class StoreNNode : public StoreNode {
669 public:
670 StoreNNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
671 : StoreNode(c, mem, adr, at, val, mo) {}
672 virtual int Opcode() const;
673 virtual BasicType memory_type() const { return T_NARROWOOP; }
674 };
675
676 //------------------------------StoreNKlassNode--------------------------------------
677 // Store narrow klass to memory
678 class StoreNKlassNode : public StoreNNode {
679 public:
680 StoreNKlassNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
681 : StoreNNode(c, mem, adr, at, val, mo) {}
682 virtual int Opcode() const;
683 virtual BasicType memory_type() const { return T_NARROWKLASS; }
684 };
685
686 //------------------------------StoreCMNode-----------------------------------
687 // Store card-mark byte to memory for CM
688 // The last StoreCM before a SafePoint must be preserved and occur after its "oop" store
689 // Preceeding equivalent StoreCMs may be eliminated.
690 class StoreCMNode : public StoreNode {
691 private:
692 virtual uint hash() const { return StoreNode::hash() + _oop_alias_idx; }
693 virtual uint cmp( const Node &n ) const {
694 return _oop_alias_idx == ((StoreCMNode&)n)._oop_alias_idx
695 && StoreNode::cmp(n);
696 }
697 virtual uint size_of() const { return sizeof(*this); }
698 int _oop_alias_idx; // The alias_idx of OopStore
699
700 public:
701 StoreCMNode( Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, Node *oop_store, int oop_alias_idx ) :
702 StoreNode(c, mem, adr, at, val, oop_store, MemNode::release),
703 _oop_alias_idx(oop_alias_idx) {
704 assert(_oop_alias_idx >= Compile::AliasIdxRaw ||
705 _oop_alias_idx == Compile::AliasIdxBot && Compile::current()->AliasLevel() == 0,
706 "bad oop alias idx");
707 }
708 virtual int Opcode() const;
709 virtual Node *Identity( PhaseTransform *phase );
710 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
711 virtual const Type *Value( PhaseTransform *phase ) const;
712 virtual BasicType memory_type() const { return T_VOID; } // unspecific
713 int oop_alias_idx() const { return _oop_alias_idx; }
714 };
715
716 //------------------------------LoadPLockedNode---------------------------------
717 // Load-locked a pointer from memory (either object or array).
718 // On Sparc & Intel this is implemented as a normal pointer load.
719 // On PowerPC and friends it's a real load-locked.
720 class LoadPLockedNode : public LoadPNode {
721 public:
722 LoadPLockedNode(Node *c, Node *mem, Node *adr, MemOrd mo)
723 : LoadPNode(c, mem, adr, TypeRawPtr::BOTTOM, TypeRawPtr::BOTTOM, mo) {}
724 virtual int Opcode() const;
725 virtual int store_Opcode() const { return Op_StorePConditional; }
726 virtual bool depends_only_on_test() const { return true; }
727 };
728
729 //------------------------------SCMemProjNode---------------------------------------
730 // This class defines a projection of the memory state of a store conditional node.
731 // These nodes return a value, but also update memory.
732 class SCMemProjNode : public ProjNode {
733 public:
734 enum {SCMEMPROJCON = (uint)-2};
735 SCMemProjNode( Node *src) : ProjNode( src, SCMEMPROJCON) { }
736 virtual int Opcode() const;
737 virtual bool is_CFG() const { return false; }
738 virtual const Type *bottom_type() const {return Type::MEMORY;}
739 virtual const TypePtr *adr_type() const {
740 Node* ctrl = in(0);
741 if (ctrl == NULL) return NULL; // node is dead
742 return ctrl->in(MemNode::Memory)->adr_type();
743 }
744 virtual uint ideal_reg() const { return 0;} // memory projections don't have a register
745 virtual const Type *Value( PhaseTransform *phase ) const;
746 #ifndef PRODUCT
747 virtual void dump_spec(outputStream *st) const {};
748 #endif
749 };
750
751 //------------------------------LoadStoreNode---------------------------
752 // Note: is_Mem() method returns 'true' for this class.
753 class LoadStoreNode : public Node {
754 private:
755 const Type* const _type; // What kind of value is loaded?
756 const TypePtr* _adr_type; // What kind of memory is being addressed?
757 virtual uint size_of() const; // Size is bigger
758 public:
759 LoadStoreNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at, const Type* rt, uint required );
760 virtual bool depends_only_on_test() const { return false; }
761 virtual uint match_edge(uint idx) const { return idx == MemNode::Address || idx == MemNode::ValueIn; }
762
763 virtual const Type *bottom_type() const { return _type; }
764 virtual uint ideal_reg() const;
765 virtual const class TypePtr *adr_type() const { return _adr_type; } // returns bottom_type of address
766
767 bool result_not_used() const;
768 };
769
770 class LoadStoreConditionalNode : public LoadStoreNode {
771 public:
772 enum {
773 ExpectedIn = MemNode::ValueIn+1 // One more input than MemNode
774 };
775 LoadStoreConditionalNode(Node *c, Node *mem, Node *adr, Node *val, Node *ex);
776 };
777
778 //------------------------------StorePConditionalNode---------------------------
779 // Conditionally store pointer to memory, if no change since prior
780 // load-locked. Sets flags for success or failure of the store.
781 class StorePConditionalNode : public LoadStoreConditionalNode {
782 public:
783 StorePConditionalNode( Node *c, Node *mem, Node *adr, Node *val, Node *ll ) : LoadStoreConditionalNode(c, mem, adr, val, ll) { }
784 virtual int Opcode() const;
785 // Produces flags
786 virtual uint ideal_reg() const { return Op_RegFlags; }
787 };
788
789 //------------------------------StoreIConditionalNode---------------------------
790 // Conditionally store int to memory, if no change since prior
791 // load-locked. Sets flags for success or failure of the store.
792 class StoreIConditionalNode : public LoadStoreConditionalNode {
793 public:
794 StoreIConditionalNode( Node *c, Node *mem, Node *adr, Node *val, Node *ii ) : LoadStoreConditionalNode(c, mem, adr, val, ii) { }
795 virtual int Opcode() const;
796 // Produces flags
797 virtual uint ideal_reg() const { return Op_RegFlags; }
798 };
799
800 //------------------------------StoreLConditionalNode---------------------------
801 // Conditionally store long to memory, if no change since prior
802 // load-locked. Sets flags for success or failure of the store.
803 class StoreLConditionalNode : public LoadStoreConditionalNode {
804 public:
805 StoreLConditionalNode( Node *c, Node *mem, Node *adr, Node *val, Node *ll ) : LoadStoreConditionalNode(c, mem, adr, val, ll) { }
806 virtual int Opcode() const;
807 // Produces flags
808 virtual uint ideal_reg() const { return Op_RegFlags; }
809 };
810
811
812 //------------------------------CompareAndSwapLNode---------------------------
813 class CompareAndSwapLNode : public LoadStoreConditionalNode {
814 public:
815 CompareAndSwapLNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex) : LoadStoreConditionalNode(c, mem, adr, val, ex) { }
816 virtual int Opcode() const;
817 };
818
819
820 //------------------------------CompareAndSwapINode---------------------------
821 class CompareAndSwapINode : public LoadStoreConditionalNode {
822 public:
823 CompareAndSwapINode( Node *c, Node *mem, Node *adr, Node *val, Node *ex) : LoadStoreConditionalNode(c, mem, adr, val, ex) { }
824 virtual int Opcode() const;
825 };
826
827
828 //------------------------------CompareAndSwapPNode---------------------------
829 class CompareAndSwapPNode : public LoadStoreConditionalNode {
830 public:
831 CompareAndSwapPNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex) : LoadStoreConditionalNode(c, mem, adr, val, ex) { }
832 virtual int Opcode() const;
833 };
834
835 //------------------------------CompareAndSwapNNode---------------------------
836 class CompareAndSwapNNode : public LoadStoreConditionalNode {
837 public:
838 CompareAndSwapNNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex) : LoadStoreConditionalNode(c, mem, adr, val, ex) { }
839 virtual int Opcode() const;
840 };
841
842 //------------------------------GetAndAddINode---------------------------
843 class GetAndAddINode : public LoadStoreNode {
844 public:
845 GetAndAddINode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeInt::INT, 4) { }
846 virtual int Opcode() const;
847 };
848
849 //------------------------------GetAndAddLNode---------------------------
850 class GetAndAddLNode : public LoadStoreNode {
851 public:
852 GetAndAddLNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeLong::LONG, 4) { }
853 virtual int Opcode() const;
854 };
855
856
857 //------------------------------GetAndSetINode---------------------------
858 class GetAndSetINode : public LoadStoreNode {
859 public:
860 GetAndSetINode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeInt::INT, 4) { }
861 virtual int Opcode() const;
862 };
863
864 //------------------------------GetAndSetINode---------------------------
865 class GetAndSetLNode : public LoadStoreNode {
866 public:
867 GetAndSetLNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeLong::LONG, 4) { }
868 virtual int Opcode() const;
869 };
870
871 //------------------------------GetAndSetPNode---------------------------
872 class GetAndSetPNode : public LoadStoreNode {
873 public:
874 GetAndSetPNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at, const Type* t ) : LoadStoreNode(c, mem, adr, val, at, t, 4) { }
875 virtual int Opcode() const;
876 };
877
878 //------------------------------GetAndSetNNode---------------------------
879 class GetAndSetNNode : public LoadStoreNode {
880 public:
881 GetAndSetNNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at, const Type* t ) : LoadStoreNode(c, mem, adr, val, at, t, 4) { }
882 virtual int Opcode() const;
883 };
884
885 //------------------------------ClearArray-------------------------------------
886 class ClearArrayNode: public Node {
887 public:
888 ClearArrayNode( Node *ctrl, Node *arymem, Node *word_cnt, Node *base )
889 : Node(ctrl,arymem,word_cnt,base) {
890 init_class_id(Class_ClearArray);
891 }
892 virtual int Opcode() const;
893 virtual const Type *bottom_type() const { return Type::MEMORY; }
894 // ClearArray modifies array elements, and so affects only the
895 // array memory addressed by the bottom_type of its base address.
896 virtual const class TypePtr *adr_type() const;
897 virtual Node *Identity( PhaseTransform *phase );
898 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
899 virtual uint match_edge(uint idx) const;
900
901 // Clear the given area of an object or array.
902 // The start offset must always be aligned mod BytesPerInt.
903 // The end offset must always be aligned mod BytesPerLong.
904 // Return the new memory.
905 static Node* clear_memory(Node* control, Node* mem, Node* dest,
906 intptr_t start_offset,
907 intptr_t end_offset,
908 PhaseGVN* phase);
909 static Node* clear_memory(Node* control, Node* mem, Node* dest,
910 intptr_t start_offset,
911 Node* end_offset,
912 PhaseGVN* phase);
913 static Node* clear_memory(Node* control, Node* mem, Node* dest,
914 Node* start_offset,
915 Node* end_offset,
916 PhaseGVN* phase);
917 // Return allocation input memory edge if it is different instance
918 // or itself if it is the one we are looking for.
919 static bool step_through(Node** np, uint instance_id, PhaseTransform* phase);
920 };
921
922 //------------------------------MemBar-----------------------------------------
923 // There are different flavors of Memory Barriers to match the Java Memory
924 // Model. Monitor-enter and volatile-load act as Aquires: no following ref
925 // can be moved to before them. We insert a MemBar-Acquire after a FastLock or
926 // volatile-load. Monitor-exit and volatile-store act as Release: no
927 // preceding ref can be moved to after them. We insert a MemBar-Release
928 // before a FastUnlock or volatile-store. All volatiles need to be
929 // serialized, so we follow all volatile-stores with a MemBar-Volatile to
930 // separate it from any following volatile-load.
931 class MemBarNode: public MultiNode {
932 virtual uint hash() const ; // { return NO_HASH; }
933 virtual uint cmp( const Node &n ) const ; // Always fail, except on self
934
935 virtual uint size_of() const { return sizeof(*this); }
936 // Memory type this node is serializing. Usually either rawptr or bottom.
937 const TypePtr* _adr_type;
938
939 public:
940 enum {
941 Precedent = TypeFunc::Parms // optional edge to force precedence
942 };
943 MemBarNode(Compile* C, int alias_idx, Node* precedent);
944 virtual int Opcode() const = 0;
945 virtual const class TypePtr *adr_type() const { return _adr_type; }
946 virtual const Type *Value( PhaseTransform *phase ) const;
947 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
948 virtual uint match_edge(uint idx) const { return 0; }
949 virtual const Type *bottom_type() const { return TypeTuple::MEMBAR; }
950 virtual Node *match( const ProjNode *proj, const Matcher *m );
951 // Factory method. Builds a wide or narrow membar.
952 // Optional 'precedent' becomes an extra edge if not null.
953 static MemBarNode* make(Compile* C, int opcode,
954 int alias_idx = Compile::AliasIdxBot,
955 Node* precedent = NULL);
956 };
957
958 // "Acquire" - no following ref can move before (but earlier refs can
959 // follow, like an early Load stalled in cache). Requires multi-cpu
960 // visibility. Inserted after a volatile load.
961 class MemBarAcquireNode: public MemBarNode {
962 public:
963 MemBarAcquireNode(Compile* C, int alias_idx, Node* precedent)
964 : MemBarNode(C, alias_idx, precedent) {}
965 virtual int Opcode() const;
966 };
967
968 // "Acquire" - no following ref can move before (but earlier refs can
969 // follow, like an early Load stalled in cache). Requires multi-cpu
970 // visibility. Inserted independ of any load, as required
971 // for intrinsic sun.misc.Unsafe.loadFence().
972 class LoadFenceNode: public MemBarNode {
973 public:
974 LoadFenceNode(Compile* C, int alias_idx, Node* precedent)
975 : MemBarNode(C, alias_idx, precedent) {}
976 virtual int Opcode() const;
977 };
978
979 // "Release" - no earlier ref can move after (but later refs can move
980 // up, like a speculative pipelined cache-hitting Load). Requires
981 // multi-cpu visibility. Inserted before a volatile store.
982 class MemBarReleaseNode: public MemBarNode {
983 public:
984 MemBarReleaseNode(Compile* C, int alias_idx, Node* precedent)
985 : MemBarNode(C, alias_idx, precedent) {}
986 virtual int Opcode() const;
987 };
988
989 // "Release" - no earlier ref can move after (but later refs can move
990 // up, like a speculative pipelined cache-hitting Load). Requires
991 // multi-cpu visibility. Inserted independent of any store, as required
992 // for intrinsic sun.misc.Unsafe.storeFence().
993 class StoreFenceNode: public MemBarNode {
994 public:
995 StoreFenceNode(Compile* C, int alias_idx, Node* precedent)
996 : MemBarNode(C, alias_idx, precedent) {}
997 virtual int Opcode() const;
998 };
999
1000 // "Acquire" - no following ref can move before (but earlier refs can
1001 // follow, like an early Load stalled in cache). Requires multi-cpu
1002 // visibility. Inserted after a FastLock.
1003 class MemBarAcquireLockNode: public MemBarNode {
1004 public:
1005 MemBarAcquireLockNode(Compile* C, int alias_idx, Node* precedent)
1006 : MemBarNode(C, alias_idx, precedent) {}
1007 virtual int Opcode() const;
1008 };
1009
1010 // "Release" - no earlier ref can move after (but later refs can move
1011 // up, like a speculative pipelined cache-hitting Load). Requires
1012 // multi-cpu visibility. Inserted before a FastUnLock.
1013 class MemBarReleaseLockNode: public MemBarNode {
1014 public:
1015 MemBarReleaseLockNode(Compile* C, int alias_idx, Node* precedent)
1016 : MemBarNode(C, alias_idx, precedent) {}
1017 virtual int Opcode() const;
1018 };
1019
1020 class MemBarStoreStoreNode: public MemBarNode {
1021 public:
1022 MemBarStoreStoreNode(Compile* C, int alias_idx, Node* precedent)
1023 : MemBarNode(C, alias_idx, precedent) {
1024 init_class_id(Class_MemBarStoreStore);
1025 }
1026 virtual int Opcode() const;
1027 };
1028
1029 // Ordering between a volatile store and a following volatile load.
1030 // Requires multi-CPU visibility?
1031 class MemBarVolatileNode: public MemBarNode {
1032 public:
1033 MemBarVolatileNode(Compile* C, int alias_idx, Node* precedent)
1034 : MemBarNode(C, alias_idx, precedent) {}
1035 virtual int Opcode() const;
1036 };
1037
1038 // Ordering within the same CPU. Used to order unsafe memory references
1039 // inside the compiler when we lack alias info. Not needed "outside" the
1040 // compiler because the CPU does all the ordering for us.
1041 class MemBarCPUOrderNode: public MemBarNode {
1042 public:
1043 MemBarCPUOrderNode(Compile* C, int alias_idx, Node* precedent)
1044 : MemBarNode(C, alias_idx, precedent) {}
1045 virtual int Opcode() const;
1046 virtual uint ideal_reg() const { return 0; } // not matched in the AD file
1047 };
1048
1049 // Isolation of object setup after an AllocateNode and before next safepoint.
1050 // (See comment in memnode.cpp near InitializeNode::InitializeNode for semantics.)
1051 class InitializeNode: public MemBarNode {
1052 friend class AllocateNode;
1053
1054 enum {
1055 Incomplete = 0,
1056 Complete = 1,
1057 WithArraycopy = 2
1058 };
1059 int _is_complete;
1060
1061 bool _does_not_escape;
1062
1063 public:
1064 enum {
1065 Control = TypeFunc::Control,
1066 Memory = TypeFunc::Memory, // MergeMem for states affected by this op
1067 RawAddress = TypeFunc::Parms+0, // the newly-allocated raw address
1068 RawStores = TypeFunc::Parms+1 // zero or more stores (or TOP)
1069 };
1070
1071 InitializeNode(Compile* C, int adr_type, Node* rawoop);
1072 virtual int Opcode() const;
1073 virtual uint size_of() const { return sizeof(*this); }
1074 virtual uint ideal_reg() const { return 0; } // not matched in the AD file
1075 virtual const RegMask &in_RegMask(uint) const; // mask for RawAddress
1076
1077 // Manage incoming memory edges via a MergeMem on in(Memory):
1078 Node* memory(uint alias_idx);
1079
1080 // The raw memory edge coming directly from the Allocation.
1081 // The contents of this memory are *always* all-zero-bits.
1082 Node* zero_memory() { return memory(Compile::AliasIdxRaw); }
1083
1084 // Return the corresponding allocation for this initialization (or null if none).
1085 // (Note: Both InitializeNode::allocation and AllocateNode::initialization
1086 // are defined in graphKit.cpp, which sets up the bidirectional relation.)
1087 AllocateNode* allocation();
1088
1089 // Anything other than zeroing in this init?
1090 bool is_non_zero();
1091
1092 // An InitializeNode must completed before macro expansion is done.
1093 // Completion requires that the AllocateNode must be followed by
1094 // initialization of the new memory to zero, then to any initializers.
1095 bool is_complete() { return _is_complete != Incomplete; }
1096 bool is_complete_with_arraycopy() { return (_is_complete & WithArraycopy) != 0; }
1097
1098 // Mark complete. (Must not yet be complete.)
1099 void set_complete(PhaseGVN* phase);
1100 void set_complete_with_arraycopy() { _is_complete = Complete | WithArraycopy; }
1101
1102 bool does_not_escape() { return _does_not_escape; }
1103 void set_does_not_escape() { _does_not_escape = true; }
1104
1105 #ifdef ASSERT
1106 // ensure all non-degenerate stores are ordered and non-overlapping
1107 bool stores_are_sane(PhaseTransform* phase);
1108 #endif //ASSERT
1109
1110 // See if this store can be captured; return offset where it initializes.
1111 // Return 0 if the store cannot be moved (any sort of problem).
1112 intptr_t can_capture_store(StoreNode* st, PhaseTransform* phase, bool can_reshape);
1113
1114 // Capture another store; reformat it to write my internal raw memory.
1115 // Return the captured copy, else NULL if there is some sort of problem.
1116 Node* capture_store(StoreNode* st, intptr_t start, PhaseTransform* phase, bool can_reshape);
1117
1118 // Find captured store which corresponds to the range [start..start+size).
1119 // Return my own memory projection (meaning the initial zero bits)
1120 // if there is no such store. Return NULL if there is a problem.
1121 Node* find_captured_store(intptr_t start, int size_in_bytes, PhaseTransform* phase);
1122
1123 // Called when the associated AllocateNode is expanded into CFG.
1124 Node* complete_stores(Node* rawctl, Node* rawmem, Node* rawptr,
1125 intptr_t header_size, Node* size_in_bytes,
1126 PhaseGVN* phase);
1127
1128 private:
1129 void remove_extra_zeroes();
1130
1131 // Find out where a captured store should be placed (or already is placed).
1132 int captured_store_insertion_point(intptr_t start, int size_in_bytes,
1133 PhaseTransform* phase);
1134
1135 static intptr_t get_store_offset(Node* st, PhaseTransform* phase);
1136
1137 Node* make_raw_address(intptr_t offset, PhaseTransform* phase);
1138
1139 bool detect_init_independence(Node* n, int& count);
1140
1141 void coalesce_subword_stores(intptr_t header_size, Node* size_in_bytes,
1142 PhaseGVN* phase);
1143
1144 intptr_t find_next_fullword_store(uint i, PhaseGVN* phase);
1145 };
1146
1147 //------------------------------MergeMem---------------------------------------
1148 // (See comment in memnode.cpp near MergeMemNode::MergeMemNode for semantics.)
1149 class MergeMemNode: public Node {
1150 virtual uint hash() const ; // { return NO_HASH; }
1151 virtual uint cmp( const Node &n ) const ; // Always fail, except on self
1152 friend class MergeMemStream;
1153 MergeMemNode(Node* def); // clients use MergeMemNode::make
1154
1155 public:
1156 // If the input is a whole memory state, clone it with all its slices intact.
1157 // Otherwise, make a new memory state with just that base memory input.
1158 // In either case, the result is a newly created MergeMem.
1159 static MergeMemNode* make(Node* base_memory);
1160
1161 virtual int Opcode() const;
1162 virtual Node *Identity( PhaseTransform *phase );
1163 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
1164 virtual uint ideal_reg() const { return NotAMachineReg; }
1165 virtual uint match_edge(uint idx) const { return 0; }
1166 virtual const RegMask &out_RegMask() const;
1167 virtual const Type *bottom_type() const { return Type::MEMORY; }
1168 virtual const TypePtr *adr_type() const { return TypePtr::BOTTOM; }
1169 // sparse accessors
1170 // Fetch the previously stored "set_memory_at", or else the base memory.
1171 // (Caller should clone it if it is a phi-nest.)
1172 Node* memory_at(uint alias_idx) const;
1173 // set the memory, regardless of its previous value
1174 void set_memory_at(uint alias_idx, Node* n);
1175 // the "base" is the memory that provides the non-finite support
1176 Node* base_memory() const { return in(Compile::AliasIdxBot); }
1177 // warning: setting the base can implicitly set any of the other slices too
1178 void set_base_memory(Node* def);
1179 // sentinel value which denotes a copy of the base memory:
1180 Node* empty_memory() const { return in(Compile::AliasIdxTop); }
1181 static Node* make_empty_memory(); // where the sentinel comes from
1182 bool is_empty_memory(Node* n) const { assert((n == empty_memory()) == n->is_top(), "sanity"); return n->is_top(); }
1183 // hook for the iterator, to perform any necessary setup
1184 void iteration_setup(const MergeMemNode* other = NULL);
1185 // push sentinels until I am at least as long as the other (semantic no-op)
1186 void grow_to_match(const MergeMemNode* other);
1187 bool verify_sparse() const PRODUCT_RETURN0;
1188 #ifndef PRODUCT
1189 virtual void dump_spec(outputStream *st) const;
1190 #endif
1191 };
1192
1193 class MergeMemStream : public StackObj {
1194 private:
1195 MergeMemNode* _mm;
1196 const MergeMemNode* _mm2; // optional second guy, contributes non-empty iterations
1197 Node* _mm_base; // loop-invariant base memory of _mm
1198 int _idx;
1199 int _cnt;
1200 Node* _mem;
1201 Node* _mem2;
1202 int _cnt2;
1203
1204 void init(MergeMemNode* mm, const MergeMemNode* mm2 = NULL) {
1205 // subsume_node will break sparseness at times, whenever a memory slice
1206 // folds down to a copy of the base ("fat") memory. In such a case,
1207 // the raw edge will update to base, although it should be top.
1208 // This iterator will recognize either top or base_memory as an
1209 // "empty" slice. See is_empty, is_empty2, and next below.
1210 //
1211 // The sparseness property is repaired in MergeMemNode::Ideal.
1212 // As long as access to a MergeMem goes through this iterator
1213 // or the memory_at accessor, flaws in the sparseness will
1214 // never be observed.
1215 //
1216 // Also, iteration_setup repairs sparseness.
1217 assert(mm->verify_sparse(), "please, no dups of base");
1218 assert(mm2==NULL || mm2->verify_sparse(), "please, no dups of base");
1219
1220 _mm = mm;
1221 _mm_base = mm->base_memory();
1222 _mm2 = mm2;
1223 _cnt = mm->req();
1224 _idx = Compile::AliasIdxBot-1; // start at the base memory
1225 _mem = NULL;
1226 _mem2 = NULL;
1227 }
1228
1229 #ifdef ASSERT
1230 Node* check_memory() const {
1231 if (at_base_memory())
1232 return _mm->base_memory();
1233 else if ((uint)_idx < _mm->req() && !_mm->in(_idx)->is_top())
1234 return _mm->memory_at(_idx);
1235 else
1236 return _mm_base;
1237 }
1238 Node* check_memory2() const {
1239 return at_base_memory()? _mm2->base_memory(): _mm2->memory_at(_idx);
1240 }
1241 #endif
1242
1243 static bool match_memory(Node* mem, const MergeMemNode* mm, int idx) PRODUCT_RETURN0;
1244 void assert_synch() const {
1245 assert(!_mem || _idx >= _cnt || match_memory(_mem, _mm, _idx),
1246 "no side-effects except through the stream");
1247 }
1248
1249 public:
1250
1251 // expected usages:
1252 // for (MergeMemStream mms(mem->is_MergeMem()); next_non_empty(); ) { ... }
1253 // for (MergeMemStream mms(mem1, mem2); next_non_empty2(); ) { ... }
1254
1255 // iterate over one merge
1256 MergeMemStream(MergeMemNode* mm) {
1257 mm->iteration_setup();
1258 init(mm);
1259 debug_only(_cnt2 = 999);
1260 }
1261 // iterate in parallel over two merges
1262 // only iterates through non-empty elements of mm2
1263 MergeMemStream(MergeMemNode* mm, const MergeMemNode* mm2) {
1264 assert(mm2, "second argument must be a MergeMem also");
1265 ((MergeMemNode*)mm2)->iteration_setup(); // update hidden state
1266 mm->iteration_setup(mm2);
1267 init(mm, mm2);
1268 _cnt2 = mm2->req();
1269 }
1270 #ifdef ASSERT
1271 ~MergeMemStream() {
1272 assert_synch();
1273 }
1274 #endif
1275
1276 MergeMemNode* all_memory() const {
1277 return _mm;
1278 }
1279 Node* base_memory() const {
1280 assert(_mm_base == _mm->base_memory(), "no update to base memory, please");
1281 return _mm_base;
1282 }
1283 const MergeMemNode* all_memory2() const {
1284 assert(_mm2 != NULL, "");
1285 return _mm2;
1286 }
1287 bool at_base_memory() const {
1288 return _idx == Compile::AliasIdxBot;
1289 }
1290 int alias_idx() const {
1291 assert(_mem, "must call next 1st");
1292 return _idx;
1293 }
1294
1295 const TypePtr* adr_type() const {
1296 return Compile::current()->get_adr_type(alias_idx());
1297 }
1298
1299 const TypePtr* adr_type(Compile* C) const {
1300 return C->get_adr_type(alias_idx());
1301 }
1302 bool is_empty() const {
1303 assert(_mem, "must call next 1st");
1304 assert(_mem->is_top() == (_mem==_mm->empty_memory()), "correct sentinel");
1305 return _mem->is_top();
1306 }
1307 bool is_empty2() const {
1308 assert(_mem2, "must call next 1st");
1309 assert(_mem2->is_top() == (_mem2==_mm2->empty_memory()), "correct sentinel");
1310 return _mem2->is_top();
1311 }
1312 Node* memory() const {
1313 assert(!is_empty(), "must not be empty");
1314 assert_synch();
1315 return _mem;
1316 }
1317 // get the current memory, regardless of empty or non-empty status
1318 Node* force_memory() const {
1319 assert(!is_empty() || !at_base_memory(), "");
1320 // Use _mm_base to defend against updates to _mem->base_memory().
1321 Node *mem = _mem->is_top() ? _mm_base : _mem;
1322 assert(mem == check_memory(), "");
1323 return mem;
1324 }
1325 Node* memory2() const {
1326 assert(_mem2 == check_memory2(), "");
1327 return _mem2;
1328 }
1329 void set_memory(Node* mem) {
1330 if (at_base_memory()) {
1331 // Note that this does not change the invariant _mm_base.
1332 _mm->set_base_memory(mem);
1333 } else {
1334 _mm->set_memory_at(_idx, mem);
1335 }
1336 _mem = mem;
1337 assert_synch();
1338 }
1339
1340 // Recover from a side effect to the MergeMemNode.
1341 void set_memory() {
1342 _mem = _mm->in(_idx);
1343 }
1344
1345 bool next() { return next(false); }
1346 bool next2() { return next(true); }
1347
1348 bool next_non_empty() { return next_non_empty(false); }
1349 bool next_non_empty2() { return next_non_empty(true); }
1350 // next_non_empty2 can yield states where is_empty() is true
1351
1352 private:
1353 // find the next item, which might be empty
1354 bool next(bool have_mm2) {
1355 assert((_mm2 != NULL) == have_mm2, "use other next");
1356 assert_synch();
1357 if (++_idx < _cnt) {
1358 // Note: This iterator allows _mm to be non-sparse.
1359 // It behaves the same whether _mem is top or base_memory.
1360 _mem = _mm->in(_idx);
1361 if (have_mm2)
1362 _mem2 = _mm2->in((_idx < _cnt2) ? _idx : Compile::AliasIdxTop);
1363 return true;
1364 }
1365 return false;
1366 }
1367
1368 // find the next non-empty item
1369 bool next_non_empty(bool have_mm2) {
1370 while (next(have_mm2)) {
1371 if (!is_empty()) {
1372 // make sure _mem2 is filled in sensibly
1373 if (have_mm2 && _mem2->is_top()) _mem2 = _mm2->base_memory();
1374 return true;
1375 } else if (have_mm2 && !is_empty2()) {
1376 return true; // is_empty() == true
1377 }
1378 }
1379 return false;
1380 }
1381 };
1382
1383 //------------------------------Prefetch---------------------------------------
1384
1385 // Allocation prefetch which may fault, TLAB size have to be adjusted.
1386 class PrefetchAllocationNode : public Node {
1387 public:
1388 PrefetchAllocationNode(Node *mem, Node *adr) : Node(0,mem,adr) {}
1389 virtual int Opcode() const;
1390 virtual uint ideal_reg() const { return NotAMachineReg; }
1391 virtual uint match_edge(uint idx) const { return idx==2; }
1392 virtual const Type *bottom_type() const { return ( AllocatePrefetchStyle == 3 ) ? Type::MEMORY : Type::ABIO; }
1393 };
1394
1395 #endif // SHARE_VM_OPTO_MEMNODE_HPP