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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7 * published by the Free Software Foundation.
8 *
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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
13 * accompanied this code).
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23 */
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 virtual const class TypePtr *adr_type() const; // returns bottom_type of address
88
89 // Shared code for Ideal methods:
90 Node *Ideal_common(PhaseGVN *phase, bool can_reshape); // Return -1 for short-circuit NULL.
91
92 // Helper function for adr_type() implementations.
93 static const TypePtr* calculate_adr_type(const Type* t, const TypePtr* cross_check = NULL);
94
95 // Raw access function, to allow copying of adr_type efficiently in
96 // product builds and retain the debug info for debug builds.
97 const TypePtr *raw_adr_type() const {
98 #ifdef ASSERT
99 return _adr_type;
100 #else
101 return 0;
102 #endif
103 }
104
105 // Map a load or store opcode to its corresponding store opcode.
106 // (Return -1 if unknown.)
107 virtual int store_Opcode() const { return -1; }
108
109 // What is the type of the value in memory? (T_VOID mean "unspecified".)
110 virtual BasicType memory_type() const = 0;
111 virtual int memory_size() const {
112 #ifdef ASSERT
113 return type2aelembytes(memory_type(), true);
114 #else
115 return type2aelembytes(memory_type());
116 #endif
117 }
118
119 // Search through memory states which precede this node (load or store).
120 // Look for an exact match for the address, with no intervening
121 // aliased stores.
122 Node* find_previous_store(PhaseTransform* phase);
123
124 // Can this node (load or store) accurately see a stored value in
125 // the given memory state? (The state may or may not be in(Memory).)
126 Node* can_see_stored_value(Node* st, PhaseTransform* phase) const;
127
128 #ifndef PRODUCT
129 static void dump_adr_type(const Node* mem, const TypePtr* adr_type, outputStream *st);
130 virtual void dump_spec(outputStream *st) const;
131 #endif
132 };
133
134 //------------------------------LoadNode---------------------------------------
135 // Load value; requires Memory and Address
136 class LoadNode : public MemNode {
137 private:
138 // On platforms with weak memory ordering (e.g., PPC, Ia64) we distinguish
139 // loads that can be reordered, and such requiring acquire semantics to
140 // adhere to the Java specification. The required behaviour is stored in
141 // this field.
142 const MemOrd _mo;
143
144 protected:
145 virtual uint cmp(const Node &n) const;
146 virtual uint size_of() const; // Size is bigger
147 // Should LoadNode::Ideal() attempt to remove control edges?
148 virtual bool can_remove_control() const;
149 const Type* const _type; // What kind of value is loaded?
150 public:
151
152 LoadNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const Type *rt, MemOrd mo)
153 : MemNode(c,mem,adr,at), _type(rt), _mo(mo) {
154 init_class_id(Class_Load);
155 }
156 inline bool is_unordered() const { return !is_acquire(); }
157 inline bool is_acquire() const {
158 assert(_mo == unordered || _mo == acquire, "unexpected");
159 return _mo == acquire;
160 }
161
162 // Polymorphic factory method:
163 static Node* make(PhaseGVN& gvn, Node *c, Node *mem, Node *adr,
164 const TypePtr* at, const Type *rt, BasicType bt, MemOrd mo);
165
166 virtual uint hash() const; // Check the type
167
168 // Handle algebraic identities here. If we have an identity, return the Node
169 // we are equivalent to. We look for Load of a Store.
170 virtual Node *Identity( PhaseTransform *phase );
171
172 // If the load is from Field memory and the pointer is non-null, it might be possible to
173 // zero out the control input.
174 // If the offset is constant and the base is an object allocation,
175 // try to hook me up to the exact initializing store.
176 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
177
178 // Split instance field load through Phi.
179 Node* split_through_phi(PhaseGVN *phase);
180
181 // Recover original value from boxed values
182 Node *eliminate_autobox(PhaseGVN *phase);
183
184 // Compute a new Type for this node. Basically we just do the pre-check,
185 // then call the virtual add() to set the type.
186 virtual const Type *Value( PhaseTransform *phase ) const;
187
188 // Common methods for LoadKlass and LoadNKlass nodes.
189 const Type *klass_value_common( PhaseTransform *phase ) const;
190 Node *klass_identity_common( PhaseTransform *phase );
191
192 virtual uint ideal_reg() const;
193 virtual const Type *bottom_type() const;
194 // Following method is copied from TypeNode:
195 void set_type(const Type* t) {
196 assert(t != NULL, "sanity");
197 debug_only(uint check_hash = (VerifyHashTableKeys && _hash_lock) ? hash() : NO_HASH);
198 *(const Type**)&_type = t; // cast away const-ness
199 // If this node is in the hash table, make sure it doesn't need a rehash.
200 assert(check_hash == NO_HASH || check_hash == hash(), "type change must preserve hash code");
201 }
202 const Type* type() const { assert(_type != NULL, "sanity"); return _type; };
203
204 // Do not match memory edge
205 virtual uint match_edge(uint idx) const;
206
207 // Map a load opcode to its corresponding store opcode.
208 virtual int store_Opcode() const = 0;
209
210 // Check if the load's memory input is a Phi node with the same control.
211 bool is_instance_field_load_with_local_phi(Node* ctrl);
212
213 #ifndef PRODUCT
214 virtual void dump_spec(outputStream *st) const;
215 #endif
216 #ifdef ASSERT
217 // Helper function to allow a raw load without control edge for some cases
218 static bool is_immutable_value(Node* adr);
219 #endif
220 protected:
221 const Type* load_array_final_field(const TypeKlassPtr *tkls,
222 ciKlass* klass) const;
223 // depends_only_on_test is almost always true, and needs to be almost always
224 // true to enable key hoisting & commoning optimizations. However, for the
225 // special case of RawPtr loads from TLS top & end, and other loads performed by
226 // GC barriers, the control edge carries the dependence preventing hoisting past
227 // a Safepoint instead of the memory edge. (An unfortunate consequence of having
228 // Safepoints not set Raw Memory; itself an unfortunate consequence of having Nodes
229 // which produce results (new raw memory state) inside of loops preventing all
230 // manner of other optimizations). Basically, it's ugly but so is the alternative.
231 // See comment in macro.cpp, around line 125 expand_allocate_common().
232 virtual bool depends_only_on_test() const { return adr_type() != TypeRawPtr::BOTTOM; }
233
234 };
235
236 //------------------------------LoadBNode--------------------------------------
237 // Load a byte (8bits signed) from memory
238 class LoadBNode : public LoadNode {
239 public:
240 LoadBNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeInt *ti, MemOrd mo)
241 : LoadNode(c, mem, adr, at, ti, mo) {}
242 virtual int Opcode() const;
243 virtual uint ideal_reg() const { return Op_RegI; }
244 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
245 virtual const Type *Value(PhaseTransform *phase) const;
246 virtual int store_Opcode() const { return Op_StoreB; }
247 virtual BasicType memory_type() const { return T_BYTE; }
248 };
249
250 //------------------------------LoadUBNode-------------------------------------
251 // Load a unsigned byte (8bits unsigned) from memory
252 class LoadUBNode : public LoadNode {
253 public:
254 LoadUBNode(Node* c, Node* mem, Node* adr, const TypePtr* at, const TypeInt* ti, MemOrd mo)
255 : LoadNode(c, mem, adr, at, ti, mo) {}
256 virtual int Opcode() const;
257 virtual uint ideal_reg() const { return Op_RegI; }
258 virtual Node* Ideal(PhaseGVN *phase, bool can_reshape);
259 virtual const Type *Value(PhaseTransform *phase) const;
260 virtual int store_Opcode() const { return Op_StoreB; }
261 virtual BasicType memory_type() const { return T_BYTE; }
262 };
263
264 //------------------------------LoadUSNode-------------------------------------
265 // Load an unsigned short/char (16bits unsigned) from memory
266 class LoadUSNode : public LoadNode {
267 public:
268 LoadUSNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeInt *ti, MemOrd mo)
269 : LoadNode(c, mem, adr, at, ti, mo) {}
270 virtual int Opcode() const;
271 virtual uint ideal_reg() const { return Op_RegI; }
272 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
273 virtual const Type *Value(PhaseTransform *phase) const;
274 virtual int store_Opcode() const { return Op_StoreC; }
275 virtual BasicType memory_type() const { return T_CHAR; }
276 };
277
278 //------------------------------LoadSNode--------------------------------------
279 // Load a short (16bits signed) from memory
280 class LoadSNode : public LoadNode {
281 public:
282 LoadSNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeInt *ti, MemOrd mo)
283 : LoadNode(c, mem, adr, at, ti, mo) {}
284 virtual int Opcode() const;
285 virtual uint ideal_reg() const { return Op_RegI; }
286 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
287 virtual const Type *Value(PhaseTransform *phase) const;
288 virtual int store_Opcode() const { return Op_StoreC; }
289 virtual BasicType memory_type() const { return T_SHORT; }
290 };
291
292 //------------------------------LoadINode--------------------------------------
293 // Load an integer from memory
294 class LoadINode : public LoadNode {
295 public:
296 LoadINode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeInt *ti, MemOrd mo)
297 : LoadNode(c, mem, adr, at, ti, mo) {}
298 virtual int Opcode() const;
299 virtual uint ideal_reg() const { return Op_RegI; }
300 virtual int store_Opcode() const { return Op_StoreI; }
301 virtual BasicType memory_type() const { return T_INT; }
302 };
303
304 //------------------------------LoadRangeNode----------------------------------
305 // Load an array length from the array
306 class LoadRangeNode : public LoadINode {
307 public:
308 LoadRangeNode(Node *c, Node *mem, Node *adr, const TypeInt *ti = TypeInt::POS)
309 : LoadINode(c, mem, adr, TypeAryPtr::RANGE, ti, MemNode::unordered) {}
310 virtual int Opcode() const;
311 virtual const Type *Value( PhaseTransform *phase ) const;
312 virtual Node *Identity( PhaseTransform *phase );
313 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
314 };
315
316 //------------------------------LoadLNode--------------------------------------
317 // Load a long from memory
318 class LoadLNode : public LoadNode {
319 virtual uint hash() const { return LoadNode::hash() + _require_atomic_access; }
320 virtual uint cmp( const Node &n ) const {
321 return _require_atomic_access == ((LoadLNode&)n)._require_atomic_access
322 && LoadNode::cmp(n);
323 }
324 virtual uint size_of() const { return sizeof(*this); }
325 const bool _require_atomic_access; // is piecewise load forbidden?
326
327 public:
328 LoadLNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeLong *tl,
329 MemOrd mo, bool require_atomic_access = false)
330 : LoadNode(c, mem, adr, at, tl, mo), _require_atomic_access(require_atomic_access) {}
331 virtual int Opcode() const;
332 virtual uint ideal_reg() const { return Op_RegL; }
333 virtual int store_Opcode() const { return Op_StoreL; }
334 virtual BasicType memory_type() const { return T_LONG; }
335 bool require_atomic_access() const { return _require_atomic_access; }
336 static LoadLNode* make_atomic(Node* ctl, Node* mem, Node* adr, const TypePtr* adr_type,
337 const Type* rt, MemOrd mo);
338 #ifndef PRODUCT
339 virtual void dump_spec(outputStream *st) const {
340 LoadNode::dump_spec(st);
341 if (_require_atomic_access) st->print(" Atomic!");
342 }
343 #endif
344 };
345
346 //------------------------------LoadL_unalignedNode----------------------------
347 // Load a long from unaligned memory
348 class LoadL_unalignedNode : public LoadLNode {
349 public:
350 LoadL_unalignedNode(Node *c, Node *mem, Node *adr, const TypePtr* at, MemOrd mo)
351 : LoadLNode(c, mem, adr, at, TypeLong::LONG, mo) {}
352 virtual int Opcode() const;
353 };
354
355 //------------------------------LoadFNode--------------------------------------
356 // Load a float (64 bits) from memory
357 class LoadFNode : public LoadNode {
358 public:
359 LoadFNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const Type *t, MemOrd mo)
360 : LoadNode(c, mem, adr, at, t, mo) {}
361 virtual int Opcode() const;
362 virtual uint ideal_reg() const { return Op_RegF; }
363 virtual int store_Opcode() const { return Op_StoreF; }
364 virtual BasicType memory_type() const { return T_FLOAT; }
365 };
366
367 //------------------------------LoadDNode--------------------------------------
368 // Load a double (64 bits) from memory
369 class LoadDNode : public LoadNode {
370 virtual uint hash() const { return LoadNode::hash() + _require_atomic_access; }
371 virtual uint cmp( const Node &n ) const {
372 return _require_atomic_access == ((LoadDNode&)n)._require_atomic_access
373 && LoadNode::cmp(n);
374 }
375 virtual uint size_of() const { return sizeof(*this); }
376 const bool _require_atomic_access; // is piecewise load forbidden?
377
378 public:
379 LoadDNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const Type *t,
380 MemOrd mo, bool require_atomic_access = false)
381 : LoadNode(c, mem, adr, at, t, mo), _require_atomic_access(require_atomic_access) {}
382 virtual int Opcode() const;
383 virtual uint ideal_reg() const { return Op_RegD; }
384 virtual int store_Opcode() const { return Op_StoreD; }
385 virtual BasicType memory_type() const { return T_DOUBLE; }
386 bool require_atomic_access() const { return _require_atomic_access; }
387 static LoadDNode* make_atomic(Node* ctl, Node* mem, Node* adr, const TypePtr* adr_type,
388 const Type* rt, MemOrd mo);
389 #ifndef PRODUCT
390 virtual void dump_spec(outputStream *st) const {
391 LoadNode::dump_spec(st);
392 if (_require_atomic_access) st->print(" Atomic!");
393 }
394 #endif
395 };
396
397 //------------------------------LoadD_unalignedNode----------------------------
398 // Load a double from unaligned memory
399 class LoadD_unalignedNode : public LoadDNode {
400 public:
401 LoadD_unalignedNode(Node *c, Node *mem, Node *adr, const TypePtr* at, MemOrd mo)
402 : LoadDNode(c, mem, adr, at, Type::DOUBLE, mo) {}
403 virtual int Opcode() const;
404 };
405
406 //------------------------------LoadPNode--------------------------------------
407 // Load a pointer from memory (either object or array)
408 class LoadPNode : public LoadNode {
409 public:
410 LoadPNode(Node *c, Node *mem, Node *adr, const TypePtr *at, const TypePtr* t, MemOrd mo)
411 : LoadNode(c, mem, adr, at, t, mo) {}
412 virtual int Opcode() const;
413 virtual uint ideal_reg() const { return Op_RegP; }
414 virtual int store_Opcode() const { return Op_StoreP; }
415 virtual BasicType memory_type() const { return T_ADDRESS; }
416 };
417
418
419 //------------------------------LoadNNode--------------------------------------
420 // Load a narrow oop from memory (either object or array)
421 class LoadNNode : public LoadNode {
422 public:
423 LoadNNode(Node *c, Node *mem, Node *adr, const TypePtr *at, const Type* t, MemOrd mo)
424 : LoadNode(c, mem, adr, at, t, mo) {}
425 virtual int Opcode() const;
426 virtual uint ideal_reg() const { return Op_RegN; }
427 virtual int store_Opcode() const { return Op_StoreN; }
428 virtual BasicType memory_type() const { return T_NARROWOOP; }
429 };
430
431 //------------------------------LoadKlassNode----------------------------------
432 // Load a Klass from an object
433 class LoadKlassNode : public LoadPNode {
434 protected:
435 // In most cases, LoadKlassNode does not have the control input set. If the control
436 // input is set, it must not be removed (by LoadNode::Ideal()).
437 virtual bool can_remove_control() const;
438 public:
439 LoadKlassNode(Node *c, Node *mem, Node *adr, const TypePtr *at, const TypeKlassPtr *tk, MemOrd mo)
440 : LoadPNode(c, mem, adr, at, tk, mo) {}
441 virtual int Opcode() const;
442 virtual const Type *Value( PhaseTransform *phase ) const;
443 virtual Node *Identity( PhaseTransform *phase );
444 virtual bool depends_only_on_test() const { return true; }
445
446 // Polymorphic factory method:
447 static Node* make(PhaseGVN& gvn, Node* ctl, Node* mem, Node* adr, const TypePtr* at,
448 const TypeKlassPtr* tk = TypeKlassPtr::OBJECT);
449 };
450
451 //------------------------------LoadNKlassNode---------------------------------
452 // Load a narrow Klass from an object.
453 class LoadNKlassNode : public LoadNNode {
454 public:
455 LoadNKlassNode(Node *c, Node *mem, Node *adr, const TypePtr *at, const TypeNarrowKlass *tk, MemOrd mo)
456 : LoadNNode(c, mem, adr, at, tk, mo) {}
457 virtual int Opcode() const;
458 virtual uint ideal_reg() const { return Op_RegN; }
459 virtual int store_Opcode() const { return Op_StoreNKlass; }
460 virtual BasicType memory_type() const { return T_NARROWKLASS; }
461
462 virtual const Type *Value( PhaseTransform *phase ) const;
463 virtual Node *Identity( PhaseTransform *phase );
464 virtual bool depends_only_on_test() const { return true; }
465 };
466
467
468 //------------------------------StoreNode--------------------------------------
469 // Store value; requires Store, Address and Value
470 class StoreNode : public MemNode {
471 private:
472 // On platforms with weak memory ordering (e.g., PPC, Ia64) we distinguish
473 // stores that can be reordered, and such requiring release semantics to
474 // adhere to the Java specification. The required behaviour is stored in
475 // this field.
476 const MemOrd _mo;
477 // Needed for proper cloning.
478 virtual uint size_of() const { return sizeof(*this); }
479 protected:
480 virtual uint cmp( const Node &n ) const;
481 virtual bool depends_only_on_test() const { return false; }
482
483 Node *Ideal_masked_input (PhaseGVN *phase, uint mask);
484 Node *Ideal_sign_extended_input(PhaseGVN *phase, int num_bits);
485
486 public:
487 // We must ensure that stores of object references will be visible
488 // only after the object's initialization. So the callers of this
489 // procedure must indicate that the store requires `release'
490 // semantics, if the stored value is an object reference that might
491 // point to a new object and may become externally visible.
492 StoreNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
493 : MemNode(c, mem, adr, at, val), _mo(mo) {
494 init_class_id(Class_Store);
495 }
496 StoreNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, Node *oop_store, MemOrd mo)
497 : MemNode(c, mem, adr, at, val, oop_store), _mo(mo) {
498 init_class_id(Class_Store);
499 }
500
501 inline bool is_unordered() const { return !is_release(); }
502 inline bool is_release() const {
503 assert((_mo == unordered || _mo == release), "unexpected");
504 return _mo == release;
505 }
506
507 // Conservatively release stores of object references in order to
508 // ensure visibility of object initialization.
509 static inline MemOrd release_if_reference(const BasicType t) {
510 #ifdef AARCH64
511 // AArch64 doesn't need a release store here because object
512 // initialization contains the necessary barriers.
513 return unordered;
514 #else
515 const MemOrd mo = (t == T_ARRAY ||
516 t == T_ADDRESS || // Might be the address of an object reference (`boxing').
517 t == T_OBJECT) ? release : unordered;
518 return mo;
519 #endif
520 }
521
522 // Polymorphic factory method
523 //
524 // We must ensure that stores of object references will be visible
525 // only after the object's initialization. So the callers of this
526 // procedure must indicate that the store requires `release'
527 // semantics, if the stored value is an object reference that might
528 // point to a new object and may become externally visible.
529 static StoreNode* make(PhaseGVN& gvn, Node *c, Node *mem, Node *adr,
530 const TypePtr* at, Node *val, BasicType bt, MemOrd mo);
531
532 virtual uint hash() const; // Check the type
533
534 // If the store is to Field memory and the pointer is non-null, we can
535 // zero out the control input.
536 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
537
538 // Compute a new Type for this node. Basically we just do the pre-check,
539 // then call the virtual add() to set the type.
540 virtual const Type *Value( PhaseTransform *phase ) const;
541
542 // Check for identity function on memory (Load then Store at same address)
543 virtual Node *Identity( PhaseTransform *phase );
544
545 // Do not match memory edge
546 virtual uint match_edge(uint idx) const;
547
548 virtual const Type *bottom_type() const; // returns Type::MEMORY
549
550 // Map a store opcode to its corresponding own opcode, trivially.
551 virtual int store_Opcode() const { return Opcode(); }
552
553 // have all possible loads of the value stored been optimized away?
554 bool value_never_loaded(PhaseTransform *phase) const;
555 };
556
557 //------------------------------StoreBNode-------------------------------------
558 // Store byte to memory
559 class StoreBNode : public StoreNode {
560 public:
561 StoreBNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
562 : StoreNode(c, mem, adr, at, val, mo) {}
563 virtual int Opcode() const;
564 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
565 virtual BasicType memory_type() const { return T_BYTE; }
566 };
567
568 //------------------------------StoreCNode-------------------------------------
569 // Store char/short to memory
570 class StoreCNode : public StoreNode {
571 public:
572 StoreCNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
573 : StoreNode(c, mem, adr, at, val, mo) {}
574 virtual int Opcode() const;
575 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
576 virtual BasicType memory_type() const { return T_CHAR; }
577 };
578
579 //------------------------------StoreINode-------------------------------------
580 // Store int to memory
581 class StoreINode : public StoreNode {
582 public:
583 StoreINode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
584 : StoreNode(c, mem, adr, at, val, mo) {}
585 virtual int Opcode() const;
586 virtual BasicType memory_type() const { return T_INT; }
587 };
588
589 //------------------------------StoreLNode-------------------------------------
590 // Store long to memory
591 class StoreLNode : public StoreNode {
592 virtual uint hash() const { return StoreNode::hash() + _require_atomic_access; }
593 virtual uint cmp( const Node &n ) const {
594 return _require_atomic_access == ((StoreLNode&)n)._require_atomic_access
595 && StoreNode::cmp(n);
596 }
597 virtual uint size_of() const { return sizeof(*this); }
598 const bool _require_atomic_access; // is piecewise store forbidden?
599
600 public:
601 StoreLNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo, bool require_atomic_access = false)
602 : StoreNode(c, mem, adr, at, val, mo), _require_atomic_access(require_atomic_access) {}
603 virtual int Opcode() const;
604 virtual BasicType memory_type() const { return T_LONG; }
605 bool require_atomic_access() const { return _require_atomic_access; }
606 static StoreLNode* make_atomic(Node* ctl, Node* mem, Node* adr, const TypePtr* adr_type, Node* val, MemOrd mo);
607 #ifndef PRODUCT
608 virtual void dump_spec(outputStream *st) const {
609 StoreNode::dump_spec(st);
610 if (_require_atomic_access) st->print(" Atomic!");
611 }
612 #endif
613 };
614
615 //------------------------------StoreFNode-------------------------------------
616 // Store float to memory
617 class StoreFNode : public StoreNode {
618 public:
619 StoreFNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
620 : StoreNode(c, mem, adr, at, val, mo) {}
621 virtual int Opcode() const;
622 virtual BasicType memory_type() const { return T_FLOAT; }
623 };
624
625 //------------------------------StoreDNode-------------------------------------
626 // Store double to memory
627 class StoreDNode : public StoreNode {
628 virtual uint hash() const { return StoreNode::hash() + _require_atomic_access; }
629 virtual uint cmp( const Node &n ) const {
630 return _require_atomic_access == ((StoreDNode&)n)._require_atomic_access
631 && StoreNode::cmp(n);
632 }
633 virtual uint size_of() const { return sizeof(*this); }
634 const bool _require_atomic_access; // is piecewise store forbidden?
635 public:
636 StoreDNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val,
637 MemOrd mo, bool require_atomic_access = false)
638 : StoreNode(c, mem, adr, at, val, mo), _require_atomic_access(require_atomic_access) {}
639 virtual int Opcode() const;
640 virtual BasicType memory_type() const { return T_DOUBLE; }
641 bool require_atomic_access() const { return _require_atomic_access; }
642 static StoreDNode* make_atomic(Node* ctl, Node* mem, Node* adr, const TypePtr* adr_type, Node* val, MemOrd mo);
643 #ifndef PRODUCT
644 virtual void dump_spec(outputStream *st) const {
645 StoreNode::dump_spec(st);
646 if (_require_atomic_access) st->print(" Atomic!");
647 }
648 #endif
649
650 };
651
652 //------------------------------StorePNode-------------------------------------
653 // Store pointer to memory
654 class StorePNode : public StoreNode {
655 public:
656 StorePNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
657 : StoreNode(c, mem, adr, at, val, mo) {}
658 virtual int Opcode() const;
659 virtual BasicType memory_type() const { return T_ADDRESS; }
660 };
661
662 //------------------------------StoreNNode-------------------------------------
663 // Store narrow oop to memory
664 class StoreNNode : public StoreNode {
665 public:
666 StoreNNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
667 : StoreNode(c, mem, adr, at, val, mo) {}
668 virtual int Opcode() const;
669 virtual BasicType memory_type() const { return T_NARROWOOP; }
670 };
671
672 //------------------------------StoreNKlassNode--------------------------------------
673 // Store narrow klass to memory
674 class StoreNKlassNode : public StoreNNode {
675 public:
676 StoreNKlassNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
677 : StoreNNode(c, mem, adr, at, val, mo) {}
678 virtual int Opcode() const;
679 virtual BasicType memory_type() const { return T_NARROWKLASS; }
680 };
681
682 //------------------------------StoreCMNode-----------------------------------
683 // Store card-mark byte to memory for CM
684 // The last StoreCM before a SafePoint must be preserved and occur after its "oop" store
685 // Preceeding equivalent StoreCMs may be eliminated.
686 class StoreCMNode : public StoreNode {
687 private:
688 virtual uint hash() const { return StoreNode::hash() + _oop_alias_idx; }
689 virtual uint cmp( const Node &n ) const {
690 return _oop_alias_idx == ((StoreCMNode&)n)._oop_alias_idx
691 && StoreNode::cmp(n);
692 }
693 virtual uint size_of() const { return sizeof(*this); }
694 int _oop_alias_idx; // The alias_idx of OopStore
695
696 public:
697 StoreCMNode( Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, Node *oop_store, int oop_alias_idx ) :
698 StoreNode(c, mem, adr, at, val, oop_store, MemNode::release),
699 _oop_alias_idx(oop_alias_idx) {
700 assert(_oop_alias_idx >= Compile::AliasIdxRaw ||
701 _oop_alias_idx == Compile::AliasIdxBot && Compile::current()->AliasLevel() == 0,
702 "bad oop alias idx");
703 }
704 virtual int Opcode() const;
705 virtual Node *Identity( PhaseTransform *phase );
706 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
707 virtual const Type *Value( PhaseTransform *phase ) const;
708 virtual BasicType memory_type() const { return T_VOID; } // unspecific
709 int oop_alias_idx() const { return _oop_alias_idx; }
710 };
711
712 //------------------------------LoadPLockedNode---------------------------------
713 // Load-locked a pointer from memory (either object or array).
714 // On Sparc & Intel this is implemented as a normal pointer load.
715 // On PowerPC and friends it's a real load-locked.
716 class LoadPLockedNode : public LoadPNode {
717 public:
718 LoadPLockedNode(Node *c, Node *mem, Node *adr, MemOrd mo)
719 : LoadPNode(c, mem, adr, TypeRawPtr::BOTTOM, TypeRawPtr::BOTTOM, mo) {}
720 virtual int Opcode() const;
721 virtual int store_Opcode() const { return Op_StorePConditional; }
722 virtual bool depends_only_on_test() const { return true; }
723 };
724
725 //------------------------------SCMemProjNode---------------------------------------
726 // This class defines a projection of the memory state of a store conditional node.
727 // These nodes return a value, but also update memory.
728 class SCMemProjNode : public ProjNode {
729 public:
730 enum {SCMEMPROJCON = (uint)-2};
731 SCMemProjNode( Node *src) : ProjNode( src, SCMEMPROJCON) { }
732 virtual int Opcode() const;
733 virtual bool is_CFG() const { return false; }
734 virtual const Type *bottom_type() const {return Type::MEMORY;}
735 virtual const TypePtr *adr_type() const {
736 Node* ctrl = in(0);
737 if (ctrl == NULL) return NULL; // node is dead
738 return ctrl->in(MemNode::Memory)->adr_type();
739 }
740 virtual uint ideal_reg() const { return 0;} // memory projections don't have a register
741 virtual const Type *Value( PhaseTransform *phase ) const;
742 #ifndef PRODUCT
743 virtual void dump_spec(outputStream *st) const {};
744 #endif
745 };
746
747 //------------------------------LoadStoreNode---------------------------
748 // Note: is_Mem() method returns 'true' for this class.
749 class LoadStoreNode : public Node {
750 private:
751 const Type* const _type; // What kind of value is loaded?
752 const TypePtr* _adr_type; // What kind of memory is being addressed?
753 virtual uint size_of() const; // Size is bigger
754 public:
755 LoadStoreNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at, const Type* rt, uint required );
756 virtual bool depends_only_on_test() const { return false; }
757 virtual uint match_edge(uint idx) const { return idx == MemNode::Address || idx == MemNode::ValueIn; }
758
759 virtual const Type *bottom_type() const { return _type; }
760 virtual uint ideal_reg() const;
761 virtual const class TypePtr *adr_type() const { return _adr_type; } // returns bottom_type of address
762
763 bool result_not_used() const;
764 };
765
766 class LoadStoreConditionalNode : public LoadStoreNode {
767 public:
768 enum {
769 ExpectedIn = MemNode::ValueIn+1 // One more input than MemNode
770 };
771 LoadStoreConditionalNode(Node *c, Node *mem, Node *adr, Node *val, Node *ex);
772 };
773
774 //------------------------------StorePConditionalNode---------------------------
775 // Conditionally store pointer to memory, if no change since prior
776 // load-locked. Sets flags for success or failure of the store.
777 class StorePConditionalNode : public LoadStoreConditionalNode {
778 public:
779 StorePConditionalNode( Node *c, Node *mem, Node *adr, Node *val, Node *ll ) : LoadStoreConditionalNode(c, mem, adr, val, ll) { }
780 virtual int Opcode() const;
781 // Produces flags
782 virtual uint ideal_reg() const { return Op_RegFlags; }
783 };
784
785 //------------------------------StoreIConditionalNode---------------------------
786 // Conditionally store int to memory, if no change since prior
787 // load-locked. Sets flags for success or failure of the store.
788 class StoreIConditionalNode : public LoadStoreConditionalNode {
789 public:
790 StoreIConditionalNode( Node *c, Node *mem, Node *adr, Node *val, Node *ii ) : LoadStoreConditionalNode(c, mem, adr, val, ii) { }
791 virtual int Opcode() const;
792 // Produces flags
793 virtual uint ideal_reg() const { return Op_RegFlags; }
794 };
795
796 //------------------------------StoreLConditionalNode---------------------------
797 // Conditionally store long to memory, if no change since prior
798 // load-locked. Sets flags for success or failure of the store.
799 class StoreLConditionalNode : public LoadStoreConditionalNode {
800 public:
801 StoreLConditionalNode( Node *c, Node *mem, Node *adr, Node *val, Node *ll ) : LoadStoreConditionalNode(c, mem, adr, val, ll) { }
802 virtual int Opcode() const;
803 // Produces flags
804 virtual uint ideal_reg() const { return Op_RegFlags; }
805 };
806
807
808 //------------------------------CompareAndSwapLNode---------------------------
809 class CompareAndSwapLNode : public LoadStoreConditionalNode {
810 public:
811 CompareAndSwapLNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex) : LoadStoreConditionalNode(c, mem, adr, val, ex) { }
812 virtual int Opcode() const;
813 };
814
815
816 //------------------------------CompareAndSwapINode---------------------------
817 class CompareAndSwapINode : public LoadStoreConditionalNode {
818 public:
819 CompareAndSwapINode( Node *c, Node *mem, Node *adr, Node *val, Node *ex) : LoadStoreConditionalNode(c, mem, adr, val, ex) { }
820 virtual int Opcode() const;
821 };
822
823
824 //------------------------------CompareAndSwapPNode---------------------------
825 class CompareAndSwapPNode : public LoadStoreConditionalNode {
826 public:
827 CompareAndSwapPNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex) : LoadStoreConditionalNode(c, mem, adr, val, ex) { }
828 virtual int Opcode() const;
829 };
830
831 //------------------------------CompareAndSwapNNode---------------------------
832 class CompareAndSwapNNode : public LoadStoreConditionalNode {
833 public:
834 CompareAndSwapNNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex) : LoadStoreConditionalNode(c, mem, adr, val, ex) { }
835 virtual int Opcode() const;
836 };
837
838 //------------------------------GetAndAddINode---------------------------
839 class GetAndAddINode : public LoadStoreNode {
840 public:
841 GetAndAddINode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeInt::INT, 4) { }
842 virtual int Opcode() const;
843 };
844
845 //------------------------------GetAndAddLNode---------------------------
846 class GetAndAddLNode : public LoadStoreNode {
847 public:
848 GetAndAddLNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeLong::LONG, 4) { }
849 virtual int Opcode() const;
850 };
851
852
853 //------------------------------GetAndSetINode---------------------------
854 class GetAndSetINode : public LoadStoreNode {
855 public:
856 GetAndSetINode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeInt::INT, 4) { }
857 virtual int Opcode() const;
858 };
859
860 //------------------------------GetAndSetINode---------------------------
861 class GetAndSetLNode : public LoadStoreNode {
862 public:
863 GetAndSetLNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeLong::LONG, 4) { }
864 virtual int Opcode() const;
865 };
866
867 //------------------------------GetAndSetPNode---------------------------
868 class GetAndSetPNode : public LoadStoreNode {
869 public:
870 GetAndSetPNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at, const Type* t ) : LoadStoreNode(c, mem, adr, val, at, t, 4) { }
871 virtual int Opcode() const;
872 };
873
874 //------------------------------GetAndSetNNode---------------------------
875 class GetAndSetNNode : public LoadStoreNode {
876 public:
877 GetAndSetNNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at, const Type* t ) : LoadStoreNode(c, mem, adr, val, at, t, 4) { }
878 virtual int Opcode() const;
879 };
880
881 //------------------------------ClearArray-------------------------------------
882 class ClearArrayNode: public Node {
883 public:
884 ClearArrayNode( Node *ctrl, Node *arymem, Node *word_cnt, Node *base )
885 : Node(ctrl,arymem,word_cnt,base) {
886 init_class_id(Class_ClearArray);
887 }
888 virtual int Opcode() const;
889 virtual const Type *bottom_type() const { return Type::MEMORY; }
890 // ClearArray modifies array elements, and so affects only the
891 // array memory addressed by the bottom_type of its base address.
892 virtual const class TypePtr *adr_type() const;
893 virtual Node *Identity( PhaseTransform *phase );
894 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
895 virtual uint match_edge(uint idx) const;
896
897 // Clear the given area of an object or array.
898 // The start offset must always be aligned mod BytesPerInt.
899 // The end offset must always be aligned mod BytesPerLong.
900 // Return the new memory.
901 static Node* clear_memory(Node* control, Node* mem, Node* dest,
902 intptr_t start_offset,
903 intptr_t end_offset,
904 PhaseGVN* phase);
905 static Node* clear_memory(Node* control, Node* mem, Node* dest,
906 intptr_t start_offset,
907 Node* end_offset,
908 PhaseGVN* phase);
909 static Node* clear_memory(Node* control, Node* mem, Node* dest,
910 Node* start_offset,
911 Node* end_offset,
912 PhaseGVN* phase);
913 // Return allocation input memory edge if it is different instance
914 // or itself if it is the one we are looking for.
915 static bool step_through(Node** np, uint instance_id, PhaseTransform* phase);
916 };
917
918 //------------------------------MemBar-----------------------------------------
919 // There are different flavors of Memory Barriers to match the Java Memory
920 // Model. Monitor-enter and volatile-load act as Aquires: no following ref
921 // can be moved to before them. We insert a MemBar-Acquire after a FastLock or
922 // volatile-load. Monitor-exit and volatile-store act as Release: no
923 // preceding ref can be moved to after them. We insert a MemBar-Release
924 // before a FastUnlock or volatile-store. All volatiles need to be
925 // serialized, so we follow all volatile-stores with a MemBar-Volatile to
926 // separate it from any following volatile-load.
927 class MemBarNode: public MultiNode {
928 virtual uint hash() const ; // { return NO_HASH; }
929 virtual uint cmp( const Node &n ) const ; // Always fail, except on self
930
931 virtual uint size_of() const { return sizeof(*this); }
932 // Memory type this node is serializing. Usually either rawptr or bottom.
933 const TypePtr* _adr_type;
934
935 public:
936 enum {
937 Precedent = TypeFunc::Parms // optional edge to force precedence
938 };
939 MemBarNode(Compile* C, int alias_idx, Node* precedent);
940 virtual int Opcode() const = 0;
941 virtual const class TypePtr *adr_type() const { return _adr_type; }
942 virtual const Type *Value( PhaseTransform *phase ) const;
943 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
944 virtual uint match_edge(uint idx) const { return 0; }
945 virtual const Type *bottom_type() const { return TypeTuple::MEMBAR; }
946 virtual Node *match( const ProjNode *proj, const Matcher *m );
947 // Factory method. Builds a wide or narrow membar.
948 // Optional 'precedent' becomes an extra edge if not null.
949 static MemBarNode* make(Compile* C, int opcode,
950 int alias_idx = Compile::AliasIdxBot,
951 Node* precedent = NULL);
952 };
953
954 // "Acquire" - no following ref can move before (but earlier refs can
955 // follow, like an early Load stalled in cache). Requires multi-cpu
956 // visibility. Inserted after a volatile load.
957 class MemBarAcquireNode: public MemBarNode {
958 public:
959 MemBarAcquireNode(Compile* C, int alias_idx, Node* precedent)
960 : MemBarNode(C, alias_idx, precedent) {}
961 virtual int Opcode() const;
962 };
963
964 // "Acquire" - no following ref can move before (but earlier refs can
965 // follow, like an early Load stalled in cache). Requires multi-cpu
966 // visibility. Inserted independ of any load, as required
967 // for intrinsic sun.misc.Unsafe.loadFence().
968 class LoadFenceNode: public MemBarNode {
969 public:
970 LoadFenceNode(Compile* C, int alias_idx, Node* precedent)
971 : MemBarNode(C, alias_idx, precedent) {}
972 virtual int Opcode() const;
973 };
974
975 // "Release" - no earlier ref can move after (but later refs can move
976 // up, like a speculative pipelined cache-hitting Load). Requires
977 // multi-cpu visibility. Inserted before a volatile store.
978 class MemBarReleaseNode: public MemBarNode {
979 public:
980 MemBarReleaseNode(Compile* C, int alias_idx, Node* precedent)
981 : MemBarNode(C, alias_idx, precedent) {}
982 virtual int Opcode() const;
983 };
984
985 // "Release" - no earlier ref can move after (but later refs can move
986 // up, like a speculative pipelined cache-hitting Load). Requires
987 // multi-cpu visibility. Inserted independent of any store, as required
988 // for intrinsic sun.misc.Unsafe.storeFence().
989 class StoreFenceNode: public MemBarNode {
990 public:
991 StoreFenceNode(Compile* C, int alias_idx, Node* precedent)
992 : MemBarNode(C, alias_idx, precedent) {}
993 virtual int Opcode() const;
994 };
995
996 // "Acquire" - no following ref can move before (but earlier refs can
997 // follow, like an early Load stalled in cache). Requires multi-cpu
998 // visibility. Inserted after a FastLock.
999 class MemBarAcquireLockNode: public MemBarNode {
1000 public:
1001 MemBarAcquireLockNode(Compile* C, int alias_idx, Node* precedent)
1002 : MemBarNode(C, alias_idx, precedent) {}
1003 virtual int Opcode() const;
1004 };
1005
1006 // "Release" - no earlier ref can move after (but later refs can move
1007 // up, like a speculative pipelined cache-hitting Load). Requires
1008 // multi-cpu visibility. Inserted before a FastUnLock.
1009 class MemBarReleaseLockNode: public MemBarNode {
1010 public:
1011 MemBarReleaseLockNode(Compile* C, int alias_idx, Node* precedent)
1012 : MemBarNode(C, alias_idx, precedent) {}
1013 virtual int Opcode() const;
1014 };
1015
1016 class MemBarStoreStoreNode: public MemBarNode {
1017 public:
1018 MemBarStoreStoreNode(Compile* C, int alias_idx, Node* precedent)
1019 : MemBarNode(C, alias_idx, precedent) {
1020 init_class_id(Class_MemBarStoreStore);
1021 }
1022 virtual int Opcode() const;
1023 };
1024
1025 // Ordering between a volatile store and a following volatile load.
1026 // Requires multi-CPU visibility?
1027 class MemBarVolatileNode: public MemBarNode {
1028 public:
1029 MemBarVolatileNode(Compile* C, int alias_idx, Node* precedent)
1030 : MemBarNode(C, alias_idx, precedent) {}
1031 virtual int Opcode() const;
1032 };
1033
1034 // Ordering within the same CPU. Used to order unsafe memory references
1035 // inside the compiler when we lack alias info. Not needed "outside" the
1036 // compiler because the CPU does all the ordering for us.
1037 class MemBarCPUOrderNode: public MemBarNode {
1038 public:
1039 MemBarCPUOrderNode(Compile* C, int alias_idx, Node* precedent)
1040 : MemBarNode(C, alias_idx, precedent) {}
1041 virtual int Opcode() const;
1042 virtual uint ideal_reg() const { return 0; } // not matched in the AD file
1043 };
1044
1045 // Isolation of object setup after an AllocateNode and before next safepoint.
1046 // (See comment in memnode.cpp near InitializeNode::InitializeNode for semantics.)
1047 class InitializeNode: public MemBarNode {
1048 friend class AllocateNode;
1049
1050 enum {
1051 Incomplete = 0,
1052 Complete = 1,
1053 WithArraycopy = 2
1054 };
1055 int _is_complete;
1056
1057 bool _does_not_escape;
1058
1059 public:
1060 enum {
1061 Control = TypeFunc::Control,
1062 Memory = TypeFunc::Memory, // MergeMem for states affected by this op
1063 RawAddress = TypeFunc::Parms+0, // the newly-allocated raw address
1064 RawStores = TypeFunc::Parms+1 // zero or more stores (or TOP)
1065 };
1066
1067 InitializeNode(Compile* C, int adr_type, Node* rawoop);
1068 virtual int Opcode() const;
1069 virtual uint size_of() const { return sizeof(*this); }
1070 virtual uint ideal_reg() const { return 0; } // not matched in the AD file
1071 virtual const RegMask &in_RegMask(uint) const; // mask for RawAddress
1072
1073 // Manage incoming memory edges via a MergeMem on in(Memory):
1074 Node* memory(uint alias_idx);
1075
1076 // The raw memory edge coming directly from the Allocation.
1077 // The contents of this memory are *always* all-zero-bits.
1078 Node* zero_memory() { return memory(Compile::AliasIdxRaw); }
1079
1080 // Return the corresponding allocation for this initialization (or null if none).
1081 // (Note: Both InitializeNode::allocation and AllocateNode::initialization
1082 // are defined in graphKit.cpp, which sets up the bidirectional relation.)
1083 AllocateNode* allocation();
1084
1085 // Anything other than zeroing in this init?
1086 bool is_non_zero();
1087
1088 // An InitializeNode must completed before macro expansion is done.
1089 // Completion requires that the AllocateNode must be followed by
1090 // initialization of the new memory to zero, then to any initializers.
1091 bool is_complete() { return _is_complete != Incomplete; }
1092 bool is_complete_with_arraycopy() { return (_is_complete & WithArraycopy) != 0; }
1093
1094 // Mark complete. (Must not yet be complete.)
1095 void set_complete(PhaseGVN* phase);
1096 void set_complete_with_arraycopy() { _is_complete = Complete | WithArraycopy; }
1097
1098 bool does_not_escape() { return _does_not_escape; }
1099 void set_does_not_escape() { _does_not_escape = true; }
1100
1101 #ifdef ASSERT
1102 // ensure all non-degenerate stores are ordered and non-overlapping
1103 bool stores_are_sane(PhaseTransform* phase);
1104 #endif //ASSERT
1105
1106 // See if this store can be captured; return offset where it initializes.
1107 // Return 0 if the store cannot be moved (any sort of problem).
1108 intptr_t can_capture_store(StoreNode* st, PhaseTransform* phase, bool can_reshape);
1109
1110 // Capture another store; reformat it to write my internal raw memory.
1111 // Return the captured copy, else NULL if there is some sort of problem.
1112 Node* capture_store(StoreNode* st, intptr_t start, PhaseTransform* phase, bool can_reshape);
1113
1114 // Find captured store which corresponds to the range [start..start+size).
1115 // Return my own memory projection (meaning the initial zero bits)
1116 // if there is no such store. Return NULL if there is a problem.
1117 Node* find_captured_store(intptr_t start, int size_in_bytes, PhaseTransform* phase);
1118
1119 // Called when the associated AllocateNode is expanded into CFG.
1120 Node* complete_stores(Node* rawctl, Node* rawmem, Node* rawptr,
1121 intptr_t header_size, Node* size_in_bytes,
1122 PhaseGVN* phase);
1123
1124 private:
1125 void remove_extra_zeroes();
1126
1127 // Find out where a captured store should be placed (or already is placed).
1128 int captured_store_insertion_point(intptr_t start, int size_in_bytes,
1129 PhaseTransform* phase);
1130
1131 static intptr_t get_store_offset(Node* st, PhaseTransform* phase);
1132
1133 Node* make_raw_address(intptr_t offset, PhaseTransform* phase);
1134
1135 bool detect_init_independence(Node* n, int& count);
1136
1137 void coalesce_subword_stores(intptr_t header_size, Node* size_in_bytes,
1138 PhaseGVN* phase);
1139
1140 intptr_t find_next_fullword_store(uint i, PhaseGVN* phase);
1141 };
1142
1143 //------------------------------MergeMem---------------------------------------
1144 // (See comment in memnode.cpp near MergeMemNode::MergeMemNode for semantics.)
1145 class MergeMemNode: public Node {
1146 virtual uint hash() const ; // { return NO_HASH; }
1147 virtual uint cmp( const Node &n ) const ; // Always fail, except on self
1148 friend class MergeMemStream;
1149 MergeMemNode(Node* def); // clients use MergeMemNode::make
1150
1151 public:
1152 // If the input is a whole memory state, clone it with all its slices intact.
1153 // Otherwise, make a new memory state with just that base memory input.
1154 // In either case, the result is a newly created MergeMem.
1155 static MergeMemNode* make(Node* base_memory);
1156
1157 virtual int Opcode() const;
1158 virtual Node *Identity( PhaseTransform *phase );
1159 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
1160 virtual uint ideal_reg() const { return NotAMachineReg; }
1161 virtual uint match_edge(uint idx) const { return 0; }
1162 virtual const RegMask &out_RegMask() const;
1163 virtual const Type *bottom_type() const { return Type::MEMORY; }
1164 virtual const TypePtr *adr_type() const { return TypePtr::BOTTOM; }
1165 // sparse accessors
1166 // Fetch the previously stored "set_memory_at", or else the base memory.
1167 // (Caller should clone it if it is a phi-nest.)
1168 Node* memory_at(uint alias_idx) const;
1169 // set the memory, regardless of its previous value
1170 void set_memory_at(uint alias_idx, Node* n);
1171 // the "base" is the memory that provides the non-finite support
1172 Node* base_memory() const { return in(Compile::AliasIdxBot); }
1173 // warning: setting the base can implicitly set any of the other slices too
1174 void set_base_memory(Node* def);
1175 // sentinel value which denotes a copy of the base memory:
1176 Node* empty_memory() const { return in(Compile::AliasIdxTop); }
1177 static Node* make_empty_memory(); // where the sentinel comes from
1178 bool is_empty_memory(Node* n) const { assert((n == empty_memory()) == n->is_top(), "sanity"); return n->is_top(); }
1179 // hook for the iterator, to perform any necessary setup
1180 void iteration_setup(const MergeMemNode* other = NULL);
1181 // push sentinels until I am at least as long as the other (semantic no-op)
1182 void grow_to_match(const MergeMemNode* other);
1183 bool verify_sparse() const PRODUCT_RETURN0;
1184 #ifndef PRODUCT
1185 virtual void dump_spec(outputStream *st) const;
1186 #endif
1187 };
1188
1189 class MergeMemStream : public StackObj {
1190 private:
1191 MergeMemNode* _mm;
1192 const MergeMemNode* _mm2; // optional second guy, contributes non-empty iterations
1193 Node* _mm_base; // loop-invariant base memory of _mm
1194 int _idx;
1195 int _cnt;
1196 Node* _mem;
1197 Node* _mem2;
1198 int _cnt2;
1199
1200 void init(MergeMemNode* mm, const MergeMemNode* mm2 = NULL) {
1201 // subsume_node will break sparseness at times, whenever a memory slice
1202 // folds down to a copy of the base ("fat") memory. In such a case,
1203 // the raw edge will update to base, although it should be top.
1204 // This iterator will recognize either top or base_memory as an
1205 // "empty" slice. See is_empty, is_empty2, and next below.
1206 //
1207 // The sparseness property is repaired in MergeMemNode::Ideal.
1208 // As long as access to a MergeMem goes through this iterator
1209 // or the memory_at accessor, flaws in the sparseness will
1210 // never be observed.
1211 //
1212 // Also, iteration_setup repairs sparseness.
1213 assert(mm->verify_sparse(), "please, no dups of base");
1214 assert(mm2==NULL || mm2->verify_sparse(), "please, no dups of base");
1215
1216 _mm = mm;
1217 _mm_base = mm->base_memory();
1218 _mm2 = mm2;
1219 _cnt = mm->req();
1220 _idx = Compile::AliasIdxBot-1; // start at the base memory
1221 _mem = NULL;
1222 _mem2 = NULL;
1223 }
1224
1225 #ifdef ASSERT
1226 Node* check_memory() const {
1227 if (at_base_memory())
1228 return _mm->base_memory();
1229 else if ((uint)_idx < _mm->req() && !_mm->in(_idx)->is_top())
1230 return _mm->memory_at(_idx);
1231 else
1232 return _mm_base;
1233 }
1234 Node* check_memory2() const {
1235 return at_base_memory()? _mm2->base_memory(): _mm2->memory_at(_idx);
1236 }
1237 #endif
1238
1239 static bool match_memory(Node* mem, const MergeMemNode* mm, int idx) PRODUCT_RETURN0;
1240 void assert_synch() const {
1241 assert(!_mem || _idx >= _cnt || match_memory(_mem, _mm, _idx),
1242 "no side-effects except through the stream");
1243 }
1244
1245 public:
1246
1247 // expected usages:
1248 // for (MergeMemStream mms(mem->is_MergeMem()); next_non_empty(); ) { ... }
1249 // for (MergeMemStream mms(mem1, mem2); next_non_empty2(); ) { ... }
1250
1251 // iterate over one merge
1252 MergeMemStream(MergeMemNode* mm) {
1253 mm->iteration_setup();
1254 init(mm);
1255 debug_only(_cnt2 = 999);
1256 }
1257 // iterate in parallel over two merges
1258 // only iterates through non-empty elements of mm2
1259 MergeMemStream(MergeMemNode* mm, const MergeMemNode* mm2) {
1260 assert(mm2, "second argument must be a MergeMem also");
1261 ((MergeMemNode*)mm2)->iteration_setup(); // update hidden state
1262 mm->iteration_setup(mm2);
1263 init(mm, mm2);
1264 _cnt2 = mm2->req();
1265 }
1266 #ifdef ASSERT
1267 ~MergeMemStream() {
1268 assert_synch();
1269 }
1270 #endif
1271
1272 MergeMemNode* all_memory() const {
1273 return _mm;
1274 }
1275 Node* base_memory() const {
1276 assert(_mm_base == _mm->base_memory(), "no update to base memory, please");
1277 return _mm_base;
1278 }
1279 const MergeMemNode* all_memory2() const {
1280 assert(_mm2 != NULL, "");
1281 return _mm2;
1282 }
1283 bool at_base_memory() const {
1284 return _idx == Compile::AliasIdxBot;
1285 }
1286 int alias_idx() const {
1287 assert(_mem, "must call next 1st");
1288 return _idx;
1289 }
1290
1291 const TypePtr* adr_type() const {
1292 return Compile::current()->get_adr_type(alias_idx());
1293 }
1294
1295 const TypePtr* adr_type(Compile* C) const {
1296 return C->get_adr_type(alias_idx());
1297 }
1298 bool is_empty() const {
1299 assert(_mem, "must call next 1st");
1300 assert(_mem->is_top() == (_mem==_mm->empty_memory()), "correct sentinel");
1301 return _mem->is_top();
1302 }
1303 bool is_empty2() const {
1304 assert(_mem2, "must call next 1st");
1305 assert(_mem2->is_top() == (_mem2==_mm2->empty_memory()), "correct sentinel");
1306 return _mem2->is_top();
1307 }
1308 Node* memory() const {
1309 assert(!is_empty(), "must not be empty");
1310 assert_synch();
1311 return _mem;
1312 }
1313 // get the current memory, regardless of empty or non-empty status
1314 Node* force_memory() const {
1315 assert(!is_empty() || !at_base_memory(), "");
1316 // Use _mm_base to defend against updates to _mem->base_memory().
1317 Node *mem = _mem->is_top() ? _mm_base : _mem;
1318 assert(mem == check_memory(), "");
1319 return mem;
1320 }
1321 Node* memory2() const {
1322 assert(_mem2 == check_memory2(), "");
1323 return _mem2;
1324 }
1325 void set_memory(Node* mem) {
1326 if (at_base_memory()) {
1327 // Note that this does not change the invariant _mm_base.
1328 _mm->set_base_memory(mem);
1329 } else {
1330 _mm->set_memory_at(_idx, mem);
1331 }
1332 _mem = mem;
1333 assert_synch();
1334 }
1335
1336 // Recover from a side effect to the MergeMemNode.
1337 void set_memory() {
1338 _mem = _mm->in(_idx);
1339 }
1340
1341 bool next() { return next(false); }
1342 bool next2() { return next(true); }
1343
1344 bool next_non_empty() { return next_non_empty(false); }
1345 bool next_non_empty2() { return next_non_empty(true); }
1346 // next_non_empty2 can yield states where is_empty() is true
1347
1348 private:
1349 // find the next item, which might be empty
1350 bool next(bool have_mm2) {
1351 assert((_mm2 != NULL) == have_mm2, "use other next");
1352 assert_synch();
1353 if (++_idx < _cnt) {
1354 // Note: This iterator allows _mm to be non-sparse.
1355 // It behaves the same whether _mem is top or base_memory.
1356 _mem = _mm->in(_idx);
1357 if (have_mm2)
1358 _mem2 = _mm2->in((_idx < _cnt2) ? _idx : Compile::AliasIdxTop);
1359 return true;
1360 }
1361 return false;
1362 }
1363
1364 // find the next non-empty item
1365 bool next_non_empty(bool have_mm2) {
1366 while (next(have_mm2)) {
1367 if (!is_empty()) {
1368 // make sure _mem2 is filled in sensibly
1369 if (have_mm2 && _mem2->is_top()) _mem2 = _mm2->base_memory();
1370 return true;
1371 } else if (have_mm2 && !is_empty2()) {
1372 return true; // is_empty() == true
1373 }
1374 }
1375 return false;
1376 }
1377 };
1378
1379 //------------------------------Prefetch---------------------------------------
1380
1381 // Allocation prefetch which may fault, TLAB size have to be adjusted.
1382 class PrefetchAllocationNode : public Node {
1383 public:
1384 PrefetchAllocationNode(Node *mem, Node *adr) : Node(0,mem,adr) {}
1385 virtual int Opcode() const;
1386 virtual uint ideal_reg() const { return NotAMachineReg; }
1387 virtual uint match_edge(uint idx) const { return idx==2; }
1388 virtual const Type *bottom_type() const { return ( AllocatePrefetchStyle == 3 ) ? Type::MEMORY : Type::ABIO; }
1389 };
1390
1391 #endif // SHARE_VM_OPTO_MEMNODE_HPP