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
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
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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 private:
43 bool _unaligned_access; // Unaligned access from unsafe
44 bool _mismatched_access; // Mismatched access from unsafe: byte read in integer array for instance
45 protected:
46 #ifdef ASSERT
47 const TypePtr* _adr_type; // What kind of memory is being addressed?
48 #endif
49 virtual uint size_of() const;
50 public:
51 enum { Control, // When is it safe to do this load?
52 Memory, // Chunk of memory is being loaded from
53 Address, // Actually address, derived from base
54 ValueIn, // Value to store
55 OopStore // Preceeding oop store, only in StoreCM
56 };
57 typedef enum { unordered = 0,
58 acquire, // Load has to acquire or be succeeded by MemBarAcquire.
59 release, // Store has to release or be preceded by MemBarRelease.
60 seqcst, // LoadStore has to have both acquire and release semantics.
61 unset // The memory ordering is not set (used for testing)
62 } MemOrd;
63 protected:
64 MemNode( Node *c0, Node *c1, Node *c2, const TypePtr* at )
65 : Node(c0,c1,c2 ), _unaligned_access(false), _mismatched_access(false) {
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 )
70 : Node(c0,c1,c2,c3), _unaligned_access(false), _mismatched_access(false) {
71 init_class_id(Class_Mem);
72 debug_only(_adr_type=at; adr_type();)
73 }
74 MemNode( Node *c0, Node *c1, Node *c2, const TypePtr* at, Node *c3, Node *c4)
75 : Node(c0,c1,c2,c3,c4), _unaligned_access(false), _mismatched_access(false) {
76 init_class_id(Class_Mem);
77 debug_only(_adr_type=at; adr_type();)
78 }
79
80 virtual Node* find_previous_arraycopy(PhaseTransform* phase, Node* ld_alloc, Node*& mem, bool can_see_stored_value) const { return NULL; }
81 static bool check_if_adr_maybe_raw(Node* adr);
82
83 public:
84 // Helpers for the optimizer. Documented in memnode.cpp.
85 static bool detect_ptr_independence(Node* p1, AllocateNode* a1,
86 Node* p2, AllocateNode* a2,
87 PhaseTransform* phase);
88 static bool adr_phi_is_loop_invariant(Node* adr_phi, Node* cast);
89
90 static Node *optimize_simple_memory_chain(Node *mchain, const TypeOopPtr *t_oop, Node *load, PhaseGVN *phase);
91 static Node *optimize_memory_chain(Node *mchain, const TypePtr *t_adr, Node *load, PhaseGVN *phase);
92 // This one should probably be a phase-specific function:
93 static bool all_controls_dominate(Node* dom, Node* sub);
94
95 virtual const class TypePtr *adr_type() const; // returns bottom_type of address
96
97 // Shared code for Ideal methods:
98 Node *Ideal_common(PhaseGVN *phase, bool can_reshape); // Return -1 for short-circuit NULL.
99
100 // Helper function for adr_type() implementations.
101 static const TypePtr* calculate_adr_type(const Type* t, const TypePtr* cross_check = NULL);
102
103 // Raw access function, to allow copying of adr_type efficiently in
104 // product builds and retain the debug info for debug builds.
105 const TypePtr *raw_adr_type() const {
106 #ifdef ASSERT
107 return _adr_type;
108 #else
109 return 0;
110 #endif
111 }
112
113 // Map a load or store opcode to its corresponding store opcode.
114 // (Return -1 if unknown.)
115 virtual int store_Opcode() const { return -1; }
116
117 // What is the type of the value in memory? (T_VOID mean "unspecified".)
118 virtual BasicType memory_type() const = 0;
119 virtual int memory_size() const {
120 #ifdef ASSERT
121 return type2aelembytes(memory_type(), true);
122 #else
123 return type2aelembytes(memory_type());
124 #endif
125 }
126
127 // Search through memory states which precede this node (load or store).
128 // Look for an exact match for the address, with no intervening
129 // aliased stores.
130 Node* find_previous_store(PhaseTransform* phase);
131
132 // Can this node (load or store) accurately see a stored value in
133 // the given memory state? (The state may or may not be in(Memory).)
134 Node* can_see_stored_value(Node* st, PhaseTransform* phase) const;
135
136 void set_unaligned_access() { _unaligned_access = true; }
137 bool is_unaligned_access() const { return _unaligned_access; }
138 void set_mismatched_access() { _mismatched_access = true; }
139 bool is_mismatched_access() const { return _mismatched_access; }
140
141 #ifndef PRODUCT
142 static void dump_adr_type(const Node* mem, const TypePtr* adr_type, outputStream *st);
143 virtual void dump_spec(outputStream *st) const;
144 #endif
145 };
146
147 //------------------------------LoadNode---------------------------------------
148 // Load value; requires Memory and Address
149 class LoadNode : public MemNode {
150 public:
151 // Some loads (from unsafe) should be pinned: they don't depend only
152 // on the dominating test. The field _control_dependency below records
153 // whether that node depends only on the dominating test.
154 // Methods used to build LoadNodes pass an argument of type enum
155 // ControlDependency instead of a boolean because those methods
156 // typically have multiple boolean parameters with default values:
157 // passing the wrong boolean to one of these parameters by mistake
158 // goes easily unnoticed. Using an enum, the compiler can check that
159 // the type of a value and the type of the parameter match.
160 enum ControlDependency {
161 Pinned,
162 DependsOnlyOnTest
163 };
164 private:
165 // LoadNode::hash() doesn't take the _control_dependency field
166 // into account: If the graph already has a non-pinned LoadNode and
167 // we add a pinned LoadNode with the same inputs, it's safe for GVN
168 // to replace the pinned LoadNode with the non-pinned LoadNode,
169 // otherwise it wouldn't be safe to have a non pinned LoadNode with
170 // those inputs in the first place. If the graph already has a
171 // pinned LoadNode and we add a non pinned LoadNode with the same
172 // inputs, it's safe (but suboptimal) for GVN to replace the
173 // non-pinned LoadNode by the pinned LoadNode.
174 ControlDependency _control_dependency;
175
176 // On platforms with weak memory ordering (e.g., PPC, Ia64) we distinguish
177 // loads that can be reordered, and such requiring acquire semantics to
178 // adhere to the Java specification. The required behaviour is stored in
179 // this field.
180 const MemOrd _mo;
181
182 protected:
183 virtual uint cmp(const Node &n) const;
184 virtual uint size_of() const; // Size is bigger
185 // Should LoadNode::Ideal() attempt to remove control edges?
186 virtual bool can_remove_control() const;
187 const Type* const _type; // What kind of value is loaded?
188
189 virtual Node* find_previous_arraycopy(PhaseTransform* phase, Node* ld_alloc, Node*& mem, bool can_see_stored_value) const;
190 public:
191
192 LoadNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const Type *rt, MemOrd mo, ControlDependency control_dependency)
193 : MemNode(c,mem,adr,at), _control_dependency(control_dependency), _mo(mo), _type(rt) {
194 init_class_id(Class_Load);
195 }
196 inline bool is_unordered() const { return !is_acquire(); }
197 inline bool is_acquire() const {
198 assert(_mo == unordered || _mo == acquire, "unexpected");
199 return _mo == acquire;
200 }
201 inline bool is_unsigned() const {
202 int lop = Opcode();
203 return (lop == Op_LoadUB) || (lop == Op_LoadUS);
204 }
205
206 // Polymorphic factory method:
207 static Node* make(PhaseGVN& gvn, Node *c, Node *mem, Node *adr,
208 const TypePtr* at, const Type *rt, BasicType bt,
209 MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest,
210 bool unaligned = false, bool mismatched = false);
211
212 virtual uint hash() const; // Check the type
213
214 // Handle algebraic identities here. If we have an identity, return the Node
215 // we are equivalent to. We look for Load of a Store.
216 virtual Node* Identity(PhaseGVN* phase);
217
218 // If the load is from Field memory and the pointer is non-null, it might be possible to
219 // zero out the control input.
220 // If the offset is constant and the base is an object allocation,
221 // try to hook me up to the exact initializing store.
222 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
223
224 // Split instance field load through Phi.
225 Node* split_through_phi(PhaseGVN *phase);
226
227 // Recover original value from boxed values
228 Node *eliminate_autobox(PhaseGVN *phase);
229
230 // Compute a new Type for this node. Basically we just do the pre-check,
231 // then call the virtual add() to set the type.
232 virtual const Type* Value(PhaseGVN* phase) const;
233
234 // Common methods for LoadKlass and LoadNKlass nodes.
235 const Type* klass_value_common(PhaseGVN* phase) const;
236 Node* klass_identity_common(PhaseGVN* phase);
237
238 virtual uint ideal_reg() const;
239 virtual const Type *bottom_type() const;
240 // Following method is copied from TypeNode:
241 void set_type(const Type* t) {
242 assert(t != NULL, "sanity");
243 debug_only(uint check_hash = (VerifyHashTableKeys && _hash_lock) ? hash() : NO_HASH);
244 *(const Type**)&_type = t; // cast away const-ness
245 // If this node is in the hash table, make sure it doesn't need a rehash.
246 assert(check_hash == NO_HASH || check_hash == hash(), "type change must preserve hash code");
247 }
248 const Type* type() const { assert(_type != NULL, "sanity"); return _type; };
249
250 // Do not match memory edge
251 virtual uint match_edge(uint idx) const;
252
253 // Map a load opcode to its corresponding store opcode.
254 virtual int store_Opcode() const = 0;
255
256 // Check if the load's memory input is a Phi node with the same control.
257 bool is_instance_field_load_with_local_phi(Node* ctrl);
258
259 Node* convert_to_unsigned_load(PhaseGVN& gvn);
260 Node* convert_to_signed_load(PhaseGVN& gvn);
261
262 #ifndef PRODUCT
263 virtual void dump_spec(outputStream *st) const;
264 #endif
265 #ifdef ASSERT
266 // Helper function to allow a raw load without control edge for some cases
267 static bool is_immutable_value(Node* adr);
268 #endif
269 protected:
270 const Type* load_array_final_field(const TypeKlassPtr *tkls,
271 ciKlass* klass) const;
272
273 Node* can_see_arraycopy_value(Node* st, PhaseGVN* phase) const;
274
275 // depends_only_on_test is almost always true, and needs to be almost always
276 // true to enable key hoisting & commoning optimizations. However, for the
277 // special case of RawPtr loads from TLS top & end, and other loads performed by
278 // GC barriers, the control edge carries the dependence preventing hoisting past
279 // a Safepoint instead of the memory edge. (An unfortunate consequence of having
280 // Safepoints not set Raw Memory; itself an unfortunate consequence of having Nodes
281 // which produce results (new raw memory state) inside of loops preventing all
282 // manner of other optimizations). Basically, it's ugly but so is the alternative.
283 // See comment in macro.cpp, around line 125 expand_allocate_common().
284 virtual bool depends_only_on_test() const {
285 return adr_type() != TypeRawPtr::BOTTOM && _control_dependency == DependsOnlyOnTest;
286 }
287 };
288
289 //------------------------------LoadBNode--------------------------------------
290 // Load a byte (8bits signed) from memory
291 class LoadBNode : public LoadNode {
292 public:
293 LoadBNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeInt *ti, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
294 : LoadNode(c, mem, adr, at, ti, mo, control_dependency) {}
295 virtual int Opcode() const;
296 virtual uint ideal_reg() const { return Op_RegI; }
297 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
298 virtual const Type* Value(PhaseGVN* phase) const;
299 virtual int store_Opcode() const { return Op_StoreB; }
300 virtual BasicType memory_type() const { return T_BYTE; }
301 };
302
303 //------------------------------LoadUBNode-------------------------------------
304 // Load a unsigned byte (8bits unsigned) from memory
305 class LoadUBNode : public LoadNode {
306 public:
307 LoadUBNode(Node* c, Node* mem, Node* adr, const TypePtr* at, const TypeInt* ti, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
308 : LoadNode(c, mem, adr, at, ti, mo, control_dependency) {}
309 virtual int Opcode() const;
310 virtual uint ideal_reg() const { return Op_RegI; }
311 virtual Node* Ideal(PhaseGVN *phase, bool can_reshape);
312 virtual const Type* Value(PhaseGVN* phase) const;
313 virtual int store_Opcode() const { return Op_StoreB; }
314 virtual BasicType memory_type() const { return T_BYTE; }
315 };
316
317 //------------------------------LoadUSNode-------------------------------------
318 // Load an unsigned short/char (16bits unsigned) from memory
319 class LoadUSNode : public LoadNode {
320 public:
321 LoadUSNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeInt *ti, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
322 : LoadNode(c, mem, adr, at, ti, mo, control_dependency) {}
323 virtual int Opcode() const;
324 virtual uint ideal_reg() const { return Op_RegI; }
325 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
326 virtual const Type* Value(PhaseGVN* phase) const;
327 virtual int store_Opcode() const { return Op_StoreC; }
328 virtual BasicType memory_type() const { return T_CHAR; }
329 };
330
331 //------------------------------LoadSNode--------------------------------------
332 // Load a short (16bits signed) from memory
333 class LoadSNode : public LoadNode {
334 public:
335 LoadSNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeInt *ti, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
336 : LoadNode(c, mem, adr, at, ti, mo, control_dependency) {}
337 virtual int Opcode() const;
338 virtual uint ideal_reg() const { return Op_RegI; }
339 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
340 virtual const Type* Value(PhaseGVN* phase) const;
341 virtual int store_Opcode() const { return Op_StoreC; }
342 virtual BasicType memory_type() const { return T_SHORT; }
343 };
344
345 //------------------------------LoadINode--------------------------------------
346 // Load an integer from memory
347 class LoadINode : public LoadNode {
348 public:
349 LoadINode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeInt *ti, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
350 : LoadNode(c, mem, adr, at, ti, mo, control_dependency) {}
351 virtual int Opcode() const;
352 virtual uint ideal_reg() const { return Op_RegI; }
353 virtual int store_Opcode() const { return Op_StoreI; }
354 virtual BasicType memory_type() const { return T_INT; }
355 };
356
357 //------------------------------LoadRangeNode----------------------------------
358 // Load an array length from the array
359 class LoadRangeNode : public LoadINode {
360 public:
361 LoadRangeNode(Node *c, Node *mem, Node *adr, const TypeInt *ti = TypeInt::POS)
362 : LoadINode(c, mem, adr, TypeAryPtr::RANGE, ti, MemNode::unordered) {}
363 virtual int Opcode() const;
364 virtual const Type* Value(PhaseGVN* phase) const;
365 virtual Node* Identity(PhaseGVN* phase);
366 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
367 };
368
369 //------------------------------LoadLNode--------------------------------------
370 // Load a long from memory
371 class LoadLNode : public LoadNode {
372 virtual uint hash() const { return LoadNode::hash() + _require_atomic_access; }
373 virtual uint cmp( const Node &n ) const {
374 return _require_atomic_access == ((LoadLNode&)n)._require_atomic_access
375 && LoadNode::cmp(n);
376 }
377 virtual uint size_of() const { return sizeof(*this); }
378 const bool _require_atomic_access; // is piecewise load forbidden?
379
380 public:
381 LoadLNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeLong *tl,
382 MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest, bool require_atomic_access = false)
383 : LoadNode(c, mem, adr, at, tl, mo, control_dependency), _require_atomic_access(require_atomic_access) {}
384 virtual int Opcode() const;
385 virtual uint ideal_reg() const { return Op_RegL; }
386 virtual int store_Opcode() const { return Op_StoreL; }
387 virtual BasicType memory_type() const { return T_LONG; }
388 bool require_atomic_access() const { return _require_atomic_access; }
389 static LoadLNode* make_atomic(Node* ctl, Node* mem, Node* adr, const TypePtr* adr_type,
390 const Type* rt, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest,
391 bool unaligned = false, bool mismatched = false);
392 #ifndef PRODUCT
393 virtual void dump_spec(outputStream *st) const {
394 LoadNode::dump_spec(st);
395 if (_require_atomic_access) st->print(" Atomic!");
396 }
397 #endif
398 };
399
400 //------------------------------LoadL_unalignedNode----------------------------
401 // Load a long from unaligned memory
402 class LoadL_unalignedNode : public LoadLNode {
403 public:
404 LoadL_unalignedNode(Node *c, Node *mem, Node *adr, const TypePtr* at, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
405 : LoadLNode(c, mem, adr, at, TypeLong::LONG, mo, control_dependency) {}
406 virtual int Opcode() const;
407 };
408
409 //------------------------------LoadFNode--------------------------------------
410 // Load a float (64 bits) from memory
411 class LoadFNode : public LoadNode {
412 public:
413 LoadFNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const Type *t, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
414 : LoadNode(c, mem, adr, at, t, mo, control_dependency) {}
415 virtual int Opcode() const;
416 virtual uint ideal_reg() const { return Op_RegF; }
417 virtual int store_Opcode() const { return Op_StoreF; }
418 virtual BasicType memory_type() const { return T_FLOAT; }
419 };
420
421 //------------------------------LoadDNode--------------------------------------
422 // Load a double (64 bits) from memory
423 class LoadDNode : public LoadNode {
424 virtual uint hash() const { return LoadNode::hash() + _require_atomic_access; }
425 virtual uint cmp( const Node &n ) const {
426 return _require_atomic_access == ((LoadDNode&)n)._require_atomic_access
427 && LoadNode::cmp(n);
428 }
429 virtual uint size_of() const { return sizeof(*this); }
430 const bool _require_atomic_access; // is piecewise load forbidden?
431
432 public:
433 LoadDNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const Type *t,
434 MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest, bool require_atomic_access = false)
435 : LoadNode(c, mem, adr, at, t, mo, control_dependency), _require_atomic_access(require_atomic_access) {}
436 virtual int Opcode() const;
437 virtual uint ideal_reg() const { return Op_RegD; }
438 virtual int store_Opcode() const { return Op_StoreD; }
439 virtual BasicType memory_type() const { return T_DOUBLE; }
440 bool require_atomic_access() const { return _require_atomic_access; }
441 static LoadDNode* make_atomic(Node* ctl, Node* mem, Node* adr, const TypePtr* adr_type,
442 const Type* rt, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest,
443 bool unaligned = false, bool mismatched = false);
444 #ifndef PRODUCT
445 virtual void dump_spec(outputStream *st) const {
446 LoadNode::dump_spec(st);
447 if (_require_atomic_access) st->print(" Atomic!");
448 }
449 #endif
450 };
451
452 //------------------------------LoadD_unalignedNode----------------------------
453 // Load a double from unaligned memory
454 class LoadD_unalignedNode : public LoadDNode {
455 public:
456 LoadD_unalignedNode(Node *c, Node *mem, Node *adr, const TypePtr* at, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
457 : LoadDNode(c, mem, adr, at, Type::DOUBLE, mo, control_dependency) {}
458 virtual int Opcode() const;
459 };
460
461 //------------------------------LoadPNode--------------------------------------
462 // Load a pointer from memory (either object or array)
463 class LoadPNode : public LoadNode {
464 public:
465 LoadPNode(Node *c, Node *mem, Node *adr, const TypePtr *at, const TypePtr* t, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
466 : LoadNode(c, mem, adr, at, t, mo, control_dependency) {}
467 virtual int Opcode() const;
468 virtual uint ideal_reg() const { return Op_RegP; }
469 virtual int store_Opcode() const { return Op_StoreP; }
470 virtual BasicType memory_type() const { return T_ADDRESS; }
471 };
472
473
474 //------------------------------LoadNNode--------------------------------------
475 // Load a narrow oop from memory (either object or array)
476 class LoadNNode : public LoadNode {
477 public:
478 LoadNNode(Node *c, Node *mem, Node *adr, const TypePtr *at, const Type* t, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
479 : LoadNode(c, mem, adr, at, t, mo, control_dependency) {}
480 virtual int Opcode() const;
481 virtual uint ideal_reg() const { return Op_RegN; }
482 virtual int store_Opcode() const { return Op_StoreN; }
483 virtual BasicType memory_type() const { return T_NARROWOOP; }
484 };
485
486 //------------------------------LoadKlassNode----------------------------------
487 // Load a Klass from an object
488 class LoadKlassNode : public LoadPNode {
489 protected:
490 // In most cases, LoadKlassNode does not have the control input set. If the control
491 // input is set, it must not be removed (by LoadNode::Ideal()).
492 virtual bool can_remove_control() const;
493 public:
494 LoadKlassNode(Node *c, Node *mem, Node *adr, const TypePtr *at, const TypeKlassPtr *tk, MemOrd mo)
495 : LoadPNode(c, mem, adr, at, tk, mo) {}
496 virtual int Opcode() const;
497 virtual const Type* Value(PhaseGVN* phase) const;
498 virtual Node* Identity(PhaseGVN* phase);
499 virtual bool depends_only_on_test() const { return true; }
500
501 // Polymorphic factory method:
502 static Node* make(PhaseGVN& gvn, Node* ctl, Node* mem, Node* adr, const TypePtr* at,
503 const TypeKlassPtr* tk = TypeKlassPtr::OBJECT);
504 };
505
506 //------------------------------LoadNKlassNode---------------------------------
507 // Load a narrow Klass from an object.
508 class LoadNKlassNode : public LoadNNode {
509 public:
510 LoadNKlassNode(Node *c, Node *mem, Node *adr, const TypePtr *at, const TypeNarrowKlass *tk, MemOrd mo)
511 : LoadNNode(c, mem, adr, at, tk, mo) {}
512 virtual int Opcode() const;
513 virtual uint ideal_reg() const { return Op_RegN; }
514 virtual int store_Opcode() const { return Op_StoreNKlass; }
515 virtual BasicType memory_type() const { return T_NARROWKLASS; }
516
517 virtual const Type* Value(PhaseGVN* phase) const;
518 virtual Node* Identity(PhaseGVN* phase);
519 virtual bool depends_only_on_test() const { return true; }
520 };
521
522
523 //------------------------------StoreNode--------------------------------------
524 // Store value; requires Store, Address and Value
525 class StoreNode : public MemNode {
526 private:
527 // On platforms with weak memory ordering (e.g., PPC, Ia64) we distinguish
528 // stores that can be reordered, and such requiring release semantics to
529 // adhere to the Java specification. The required behaviour is stored in
530 // this field.
531 const MemOrd _mo;
532 // Needed for proper cloning.
533 virtual uint size_of() const { return sizeof(*this); }
534 protected:
535 virtual uint cmp( const Node &n ) const;
536 virtual bool depends_only_on_test() const { return false; }
537
538 Node *Ideal_masked_input (PhaseGVN *phase, uint mask);
539 Node *Ideal_sign_extended_input(PhaseGVN *phase, int num_bits);
540
541 public:
542 // We must ensure that stores of object references will be visible
543 // only after the object's initialization. So the callers of this
544 // procedure must indicate that the store requires `release'
545 // semantics, if the stored value is an object reference that might
546 // point to a new object and may become externally visible.
547 StoreNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
548 : MemNode(c, mem, adr, at, val), _mo(mo) {
549 init_class_id(Class_Store);
550 }
551 StoreNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, Node *oop_store, MemOrd mo)
552 : MemNode(c, mem, adr, at, val, oop_store), _mo(mo) {
553 init_class_id(Class_Store);
554 }
555
556 inline bool is_unordered() const { return !is_release(); }
557 inline bool is_release() const {
558 assert((_mo == unordered || _mo == release), "unexpected");
559 return _mo == release;
560 }
561
562 // Conservatively release stores of object references in order to
563 // ensure visibility of object initialization.
564 static inline MemOrd release_if_reference(const BasicType t) {
565 #ifdef AARCH64
566 // AArch64 doesn't need a release store here because object
567 // initialization contains the necessary barriers.
568 return unordered;
569 #else
570 const MemOrd mo = (t == T_ARRAY ||
571 t == T_ADDRESS || // Might be the address of an object reference (`boxing').
572 t == T_OBJECT) ? release : unordered;
573 return mo;
574 #endif
575 }
576
577 // Polymorphic factory method
578 //
579 // We must ensure that stores of object references will be visible
580 // only after the object's initialization. So the callers of this
581 // procedure must indicate that the store requires `release'
582 // semantics, if the stored value is an object reference that might
583 // point to a new object and may become externally visible.
584 static StoreNode* make(PhaseGVN& gvn, Node *c, Node *mem, Node *adr,
585 const TypePtr* at, Node *val, BasicType bt, MemOrd mo);
586
587 virtual uint hash() const; // Check the type
588
589 // If the store is to Field memory and the pointer is non-null, we can
590 // zero out the control input.
591 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
592
593 // Compute a new Type for this node. Basically we just do the pre-check,
594 // then call the virtual add() to set the type.
595 virtual const Type* Value(PhaseGVN* phase) const;
596
597 // Check for identity function on memory (Load then Store at same address)
598 virtual Node* Identity(PhaseGVN* phase);
599
600 // Do not match memory edge
601 virtual uint match_edge(uint idx) const;
602
603 virtual const Type *bottom_type() const; // returns Type::MEMORY
604
605 // Map a store opcode to its corresponding own opcode, trivially.
606 virtual int store_Opcode() const { return Opcode(); }
607
608 // have all possible loads of the value stored been optimized away?
609 bool value_never_loaded(PhaseTransform *phase) const;
610
611 MemBarNode* trailing_membar() const;
612 };
613
614 //------------------------------StoreBNode-------------------------------------
615 // Store byte to memory
616 class StoreBNode : public StoreNode {
617 public:
618 StoreBNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
619 : StoreNode(c, mem, adr, at, val, mo) {}
620 virtual int Opcode() const;
621 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
622 virtual BasicType memory_type() const { return T_BYTE; }
623 };
624
625 //------------------------------StoreCNode-------------------------------------
626 // Store char/short to memory
627 class StoreCNode : public StoreNode {
628 public:
629 StoreCNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
630 : StoreNode(c, mem, adr, at, val, mo) {}
631 virtual int Opcode() const;
632 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
633 virtual BasicType memory_type() const { return T_CHAR; }
634 };
635
636 //------------------------------StoreINode-------------------------------------
637 // Store int to memory
638 class StoreINode : public StoreNode {
639 public:
640 StoreINode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
641 : StoreNode(c, mem, adr, at, val, mo) {}
642 virtual int Opcode() const;
643 virtual BasicType memory_type() const { return T_INT; }
644 };
645
646 //------------------------------StoreLNode-------------------------------------
647 // Store long to memory
648 class StoreLNode : public StoreNode {
649 virtual uint hash() const { return StoreNode::hash() + _require_atomic_access; }
650 virtual uint cmp( const Node &n ) const {
651 return _require_atomic_access == ((StoreLNode&)n)._require_atomic_access
652 && StoreNode::cmp(n);
653 }
654 virtual uint size_of() const { return sizeof(*this); }
655 const bool _require_atomic_access; // is piecewise store forbidden?
656
657 public:
658 StoreLNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo, bool require_atomic_access = false)
659 : StoreNode(c, mem, adr, at, val, mo), _require_atomic_access(require_atomic_access) {}
660 virtual int Opcode() const;
661 virtual BasicType memory_type() const { return T_LONG; }
662 bool require_atomic_access() const { return _require_atomic_access; }
663 static StoreLNode* make_atomic(Node* ctl, Node* mem, Node* adr, const TypePtr* adr_type, Node* val, MemOrd mo);
664 #ifndef PRODUCT
665 virtual void dump_spec(outputStream *st) const {
666 StoreNode::dump_spec(st);
667 if (_require_atomic_access) st->print(" Atomic!");
668 }
669 #endif
670 };
671
672 //------------------------------StoreFNode-------------------------------------
673 // Store float to memory
674 class StoreFNode : public StoreNode {
675 public:
676 StoreFNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
677 : StoreNode(c, mem, adr, at, val, mo) {}
678 virtual int Opcode() const;
679 virtual BasicType memory_type() const { return T_FLOAT; }
680 };
681
682 //------------------------------StoreDNode-------------------------------------
683 // Store double to memory
684 class StoreDNode : public StoreNode {
685 virtual uint hash() const { return StoreNode::hash() + _require_atomic_access; }
686 virtual uint cmp( const Node &n ) const {
687 return _require_atomic_access == ((StoreDNode&)n)._require_atomic_access
688 && StoreNode::cmp(n);
689 }
690 virtual uint size_of() const { return sizeof(*this); }
691 const bool _require_atomic_access; // is piecewise store forbidden?
692 public:
693 StoreDNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val,
694 MemOrd mo, bool require_atomic_access = false)
695 : StoreNode(c, mem, adr, at, val, mo), _require_atomic_access(require_atomic_access) {}
696 virtual int Opcode() const;
697 virtual BasicType memory_type() const { return T_DOUBLE; }
698 bool require_atomic_access() const { return _require_atomic_access; }
699 static StoreDNode* make_atomic(Node* ctl, Node* mem, Node* adr, const TypePtr* adr_type, Node* val, MemOrd mo);
700 #ifndef PRODUCT
701 virtual void dump_spec(outputStream *st) const {
702 StoreNode::dump_spec(st);
703 if (_require_atomic_access) st->print(" Atomic!");
704 }
705 #endif
706
707 };
708
709 //------------------------------StorePNode-------------------------------------
710 // Store pointer to memory
711 class StorePNode : public StoreNode {
712 public:
713 StorePNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
714 : StoreNode(c, mem, adr, at, val, mo) {}
715 virtual int Opcode() const;
716 virtual BasicType memory_type() const { return T_ADDRESS; }
717 };
718
719 //------------------------------StoreNNode-------------------------------------
720 // Store narrow oop to memory
721 class StoreNNode : public StoreNode {
722 public:
723 StoreNNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
724 : StoreNode(c, mem, adr, at, val, mo) {}
725 virtual int Opcode() const;
726 virtual BasicType memory_type() const { return T_NARROWOOP; }
727 };
728
729 //------------------------------StoreNKlassNode--------------------------------------
730 // Store narrow klass to memory
731 class StoreNKlassNode : public StoreNNode {
732 public:
733 StoreNKlassNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
734 : StoreNNode(c, mem, adr, at, val, mo) {}
735 virtual int Opcode() const;
736 virtual BasicType memory_type() const { return T_NARROWKLASS; }
737 };
738
739 //------------------------------StoreCMNode-----------------------------------
740 // Store card-mark byte to memory for CM
741 // The last StoreCM before a SafePoint must be preserved and occur after its "oop" store
742 // Preceeding equivalent StoreCMs may be eliminated.
743 class StoreCMNode : public StoreNode {
744 private:
745 virtual uint hash() const { return StoreNode::hash() + _oop_alias_idx; }
746 virtual uint cmp( const Node &n ) const {
747 return _oop_alias_idx == ((StoreCMNode&)n)._oop_alias_idx
748 && StoreNode::cmp(n);
749 }
750 virtual uint size_of() const { return sizeof(*this); }
751 int _oop_alias_idx; // The alias_idx of OopStore
752
753 public:
754 StoreCMNode( Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, Node *oop_store, int oop_alias_idx ) :
755 StoreNode(c, mem, adr, at, val, oop_store, MemNode::release),
756 _oop_alias_idx(oop_alias_idx) {
757 assert(_oop_alias_idx >= Compile::AliasIdxRaw ||
758 _oop_alias_idx == Compile::AliasIdxBot && Compile::current()->AliasLevel() == 0,
759 "bad oop alias idx");
760 }
761 virtual int Opcode() const;
762 virtual Node* Identity(PhaseGVN* phase);
763 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
764 virtual const Type* Value(PhaseGVN* phase) const;
765 virtual BasicType memory_type() const { return T_VOID; } // unspecific
766 int oop_alias_idx() const { return _oop_alias_idx; }
767 };
768
769 //------------------------------LoadPLockedNode---------------------------------
770 // Load-locked a pointer from memory (either object or array).
771 // On Sparc & Intel this is implemented as a normal pointer load.
772 // On PowerPC and friends it's a real load-locked.
773 class LoadPLockedNode : public LoadPNode {
774 public:
775 LoadPLockedNode(Node *c, Node *mem, Node *adr, MemOrd mo)
776 : LoadPNode(c, mem, adr, TypeRawPtr::BOTTOM, TypeRawPtr::BOTTOM, mo) {}
777 virtual int Opcode() const;
778 virtual int store_Opcode() const { return Op_StorePConditional; }
779 virtual bool depends_only_on_test() const { return true; }
780 };
781
782 //------------------------------SCMemProjNode---------------------------------------
783 // This class defines a projection of the memory state of a store conditional node.
784 // These nodes return a value, but also update memory.
785 class SCMemProjNode : public ProjNode {
786 public:
787 enum {SCMEMPROJCON = (uint)-2};
788 SCMemProjNode( Node *src) : ProjNode( src, SCMEMPROJCON) { }
789 virtual int Opcode() const;
790 virtual bool is_CFG() const { return false; }
791 virtual const Type *bottom_type() const {return Type::MEMORY;}
792 virtual const TypePtr *adr_type() const {
793 Node* ctrl = in(0);
794 if (ctrl == NULL) return NULL; // node is dead
795 return ctrl->in(MemNode::Memory)->adr_type();
796 }
797 virtual uint ideal_reg() const { return 0;} // memory projections don't have a register
798 virtual const Type* Value(PhaseGVN* phase) const;
799 #ifndef PRODUCT
800 virtual void dump_spec(outputStream *st) const {};
801 #endif
802 };
803
804 //------------------------------LoadStoreNode---------------------------
805 // Note: is_Mem() method returns 'true' for this class.
806 class LoadStoreNode : public Node {
807 private:
808 const Type* const _type; // What kind of value is loaded?
809 const TypePtr* _adr_type; // What kind of memory is being addressed?
810 virtual uint size_of() const; // Size is bigger
811 public:
812 LoadStoreNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at, const Type* rt, uint required );
813 virtual bool depends_only_on_test() const { return false; }
814 virtual uint match_edge(uint idx) const { return idx == MemNode::Address || idx == MemNode::ValueIn; }
815
816 virtual const Type *bottom_type() const { return _type; }
817 virtual uint ideal_reg() const;
818 virtual const class TypePtr *adr_type() const { return _adr_type; } // returns bottom_type of address
819
820 bool result_not_used() const;
821 MemBarNode* trailing_membar() const;
822 };
823
824 class LoadStoreConditionalNode : public LoadStoreNode {
825 public:
826 enum {
827 ExpectedIn = MemNode::ValueIn+1 // One more input than MemNode
828 };
829 LoadStoreConditionalNode(Node *c, Node *mem, Node *adr, Node *val, Node *ex);
830 };
831
832 //------------------------------StorePConditionalNode---------------------------
833 // Conditionally store pointer to memory, if no change since prior
834 // load-locked. Sets flags for success or failure of the store.
835 class StorePConditionalNode : public LoadStoreConditionalNode {
836 public:
837 StorePConditionalNode( Node *c, Node *mem, Node *adr, Node *val, Node *ll ) : LoadStoreConditionalNode(c, mem, adr, val, ll) { }
838 virtual int Opcode() const;
839 // Produces flags
840 virtual uint ideal_reg() const { return Op_RegFlags; }
841 };
842
843 //------------------------------StoreIConditionalNode---------------------------
844 // Conditionally store int to memory, if no change since prior
845 // load-locked. Sets flags for success or failure of the store.
846 class StoreIConditionalNode : public LoadStoreConditionalNode {
847 public:
848 StoreIConditionalNode( Node *c, Node *mem, Node *adr, Node *val, Node *ii ) : LoadStoreConditionalNode(c, mem, adr, val, ii) { }
849 virtual int Opcode() const;
850 // Produces flags
851 virtual uint ideal_reg() const { return Op_RegFlags; }
852 };
853
854 //------------------------------StoreLConditionalNode---------------------------
855 // Conditionally store long to memory, if no change since prior
856 // load-locked. Sets flags for success or failure of the store.
857 class StoreLConditionalNode : public LoadStoreConditionalNode {
858 public:
859 StoreLConditionalNode( Node *c, Node *mem, Node *adr, Node *val, Node *ll ) : LoadStoreConditionalNode(c, mem, adr, val, ll) { }
860 virtual int Opcode() const;
861 // Produces flags
862 virtual uint ideal_reg() const { return Op_RegFlags; }
863 };
864
865 class CompareAndSwapNode : public LoadStoreConditionalNode {
866 private:
867 const MemNode::MemOrd _mem_ord;
868 public:
869 CompareAndSwapNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : LoadStoreConditionalNode(c, mem, adr, val, ex), _mem_ord(mem_ord) {}
870 MemNode::MemOrd order() const {
871 return _mem_ord;
872 }
873 };
874
875 class CompareAndExchangeNode : public LoadStoreNode {
876 private:
877 const MemNode::MemOrd _mem_ord;
878 public:
879 enum {
880 ExpectedIn = MemNode::ValueIn+1 // One more input than MemNode
881 };
882 CompareAndExchangeNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord, const TypePtr* at, const Type* t) :
883 LoadStoreNode(c, mem, adr, val, at, t, 5), _mem_ord(mem_ord) {
884 init_req(ExpectedIn, ex );
885 }
886
887 MemNode::MemOrd order() const {
888 return _mem_ord;
889 }
890 };
891
892 //------------------------------CompareAndSwapBNode---------------------------
893 class CompareAndSwapBNode : public CompareAndSwapNode {
894 public:
895 CompareAndSwapBNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
896 virtual int Opcode() const;
897 };
898
899 //------------------------------CompareAndSwapSNode---------------------------
900 class CompareAndSwapSNode : public CompareAndSwapNode {
901 public:
902 CompareAndSwapSNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
903 virtual int Opcode() const;
904 };
905
906 //------------------------------CompareAndSwapINode---------------------------
907 class CompareAndSwapINode : public CompareAndSwapNode {
908 public:
909 CompareAndSwapINode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
910 virtual int Opcode() const;
911 };
912
913 //------------------------------CompareAndSwapLNode---------------------------
914 class CompareAndSwapLNode : public CompareAndSwapNode {
915 public:
916 CompareAndSwapLNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
917 virtual int Opcode() const;
918 };
919
920 //------------------------------CompareAndSwapPNode---------------------------
921 class CompareAndSwapPNode : public CompareAndSwapNode {
922 public:
923 CompareAndSwapPNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
924 virtual int Opcode() const;
925 };
926
927 //------------------------------CompareAndSwapNNode---------------------------
928 class CompareAndSwapNNode : public CompareAndSwapNode {
929 public:
930 CompareAndSwapNNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
931 virtual int Opcode() const;
932 };
933
934 //------------------------------WeakCompareAndSwapBNode---------------------------
935 class WeakCompareAndSwapBNode : public CompareAndSwapNode {
936 public:
937 WeakCompareAndSwapBNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
938 virtual int Opcode() const;
939 };
940
941 //------------------------------WeakCompareAndSwapSNode---------------------------
942 class WeakCompareAndSwapSNode : public CompareAndSwapNode {
943 public:
944 WeakCompareAndSwapSNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
945 virtual int Opcode() const;
946 };
947
948 //------------------------------WeakCompareAndSwapINode---------------------------
949 class WeakCompareAndSwapINode : public CompareAndSwapNode {
950 public:
951 WeakCompareAndSwapINode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
952 virtual int Opcode() const;
953 };
954
955 //------------------------------WeakCompareAndSwapLNode---------------------------
956 class WeakCompareAndSwapLNode : public CompareAndSwapNode {
957 public:
958 WeakCompareAndSwapLNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
959 virtual int Opcode() const;
960 };
961
962 //------------------------------WeakCompareAndSwapPNode---------------------------
963 class WeakCompareAndSwapPNode : public CompareAndSwapNode {
964 public:
965 WeakCompareAndSwapPNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
966 virtual int Opcode() const;
967 };
968
969 //------------------------------WeakCompareAndSwapNNode---------------------------
970 class WeakCompareAndSwapNNode : public CompareAndSwapNode {
971 public:
972 WeakCompareAndSwapNNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
973 virtual int Opcode() const;
974 };
975
976 //------------------------------CompareAndExchangeBNode---------------------------
977 class CompareAndExchangeBNode : public CompareAndExchangeNode {
978 public:
979 CompareAndExchangeBNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, const TypePtr* at, MemNode::MemOrd mem_ord) : CompareAndExchangeNode(c, mem, adr, val, ex, mem_ord, at, TypeInt::BYTE) { }
980 virtual int Opcode() const;
981 };
982
983
984 //------------------------------CompareAndExchangeSNode---------------------------
985 class CompareAndExchangeSNode : public CompareAndExchangeNode {
986 public:
987 CompareAndExchangeSNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, const TypePtr* at, MemNode::MemOrd mem_ord) : CompareAndExchangeNode(c, mem, adr, val, ex, mem_ord, at, TypeInt::SHORT) { }
988 virtual int Opcode() const;
989 };
990
991 //------------------------------CompareAndExchangeLNode---------------------------
992 class CompareAndExchangeLNode : public CompareAndExchangeNode {
993 public:
994 CompareAndExchangeLNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, const TypePtr* at, MemNode::MemOrd mem_ord) : CompareAndExchangeNode(c, mem, adr, val, ex, mem_ord, at, TypeLong::LONG) { }
995 virtual int Opcode() const;
996 };
997
998
999 //------------------------------CompareAndExchangeINode---------------------------
1000 class CompareAndExchangeINode : public CompareAndExchangeNode {
1001 public:
1002 CompareAndExchangeINode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, const TypePtr* at, MemNode::MemOrd mem_ord) : CompareAndExchangeNode(c, mem, adr, val, ex, mem_ord, at, TypeInt::INT) { }
1003 virtual int Opcode() const;
1004 };
1005
1006
1007 //------------------------------CompareAndExchangePNode---------------------------
1008 class CompareAndExchangePNode : public CompareAndExchangeNode {
1009 public:
1010 CompareAndExchangePNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, const TypePtr* at, const Type* t, MemNode::MemOrd mem_ord) : CompareAndExchangeNode(c, mem, adr, val, ex, mem_ord, at, t) { }
1011 virtual int Opcode() const;
1012 };
1013
1014 //------------------------------CompareAndExchangeNNode---------------------------
1015 class CompareAndExchangeNNode : public CompareAndExchangeNode {
1016 public:
1017 CompareAndExchangeNNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, const TypePtr* at, const Type* t, MemNode::MemOrd mem_ord) : CompareAndExchangeNode(c, mem, adr, val, ex, mem_ord, at, t) { }
1018 virtual int Opcode() const;
1019 };
1020
1021 //------------------------------GetAndAddBNode---------------------------
1022 class GetAndAddBNode : public LoadStoreNode {
1023 public:
1024 GetAndAddBNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeInt::BYTE, 4) { }
1025 virtual int Opcode() const;
1026 };
1027
1028 //------------------------------GetAndAddSNode---------------------------
1029 class GetAndAddSNode : public LoadStoreNode {
1030 public:
1031 GetAndAddSNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeInt::SHORT, 4) { }
1032 virtual int Opcode() const;
1033 };
1034
1035 //------------------------------GetAndAddINode---------------------------
1036 class GetAndAddINode : public LoadStoreNode {
1037 public:
1038 GetAndAddINode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeInt::INT, 4) { }
1039 virtual int Opcode() const;
1040 };
1041
1042 //------------------------------GetAndAddLNode---------------------------
1043 class GetAndAddLNode : public LoadStoreNode {
1044 public:
1045 GetAndAddLNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeLong::LONG, 4) { }
1046 virtual int Opcode() const;
1047 };
1048
1049 //------------------------------GetAndSetBNode---------------------------
1050 class GetAndSetBNode : public LoadStoreNode {
1051 public:
1052 GetAndSetBNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeInt::BYTE, 4) { }
1053 virtual int Opcode() const;
1054 };
1055
1056 //------------------------------GetAndSetSNode---------------------------
1057 class GetAndSetSNode : public LoadStoreNode {
1058 public:
1059 GetAndSetSNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeInt::SHORT, 4) { }
1060 virtual int Opcode() const;
1061 };
1062
1063 //------------------------------GetAndSetINode---------------------------
1064 class GetAndSetINode : public LoadStoreNode {
1065 public:
1066 GetAndSetINode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeInt::INT, 4) { }
1067 virtual int Opcode() const;
1068 };
1069
1070 //------------------------------GetAndSetLNode---------------------------
1071 class GetAndSetLNode : public LoadStoreNode {
1072 public:
1073 GetAndSetLNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeLong::LONG, 4) { }
1074 virtual int Opcode() const;
1075 };
1076
1077 //------------------------------GetAndSetPNode---------------------------
1078 class GetAndSetPNode : public LoadStoreNode {
1079 public:
1080 GetAndSetPNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at, const Type* t ) : LoadStoreNode(c, mem, adr, val, at, t, 4) { }
1081 virtual int Opcode() const;
1082 };
1083
1084 //------------------------------GetAndSetNNode---------------------------
1085 class GetAndSetNNode : public LoadStoreNode {
1086 public:
1087 GetAndSetNNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at, const Type* t ) : LoadStoreNode(c, mem, adr, val, at, t, 4) { }
1088 virtual int Opcode() const;
1089 };
1090
1091 //------------------------------ClearArray-------------------------------------
1092 class ClearArrayNode: public Node {
1093 private:
1094 bool _is_large;
1095 public:
1096 ClearArrayNode( Node *ctrl, Node *arymem, Node *word_cnt, Node *base, bool is_large)
1097 : Node(ctrl,arymem,word_cnt,base), _is_large(is_large) {
1098 init_class_id(Class_ClearArray);
1099 }
1100 virtual int Opcode() const;
1101 virtual const Type *bottom_type() const { return Type::MEMORY; }
1102 // ClearArray modifies array elements, and so affects only the
1103 // array memory addressed by the bottom_type of its base address.
1104 virtual const class TypePtr *adr_type() const;
1105 virtual Node* Identity(PhaseGVN* phase);
1106 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
1107 virtual uint match_edge(uint idx) const;
1108 bool is_large() const { return _is_large; }
1109
1110 // Clear the given area of an object or array.
1111 // The start offset must always be aligned mod BytesPerInt.
1112 // The end offset must always be aligned mod BytesPerLong.
1113 // Return the new memory.
1114 static Node* clear_memory(Node* control, Node* mem, Node* dest,
1115 intptr_t start_offset,
1116 intptr_t end_offset,
1117 PhaseGVN* phase);
1118 static Node* clear_memory(Node* control, Node* mem, Node* dest,
1119 intptr_t start_offset,
1120 Node* end_offset,
1121 PhaseGVN* phase);
1122 static Node* clear_memory(Node* control, Node* mem, Node* dest,
1123 Node* start_offset,
1124 Node* end_offset,
1125 PhaseGVN* phase);
1126 // Return allocation input memory edge if it is different instance
1127 // or itself if it is the one we are looking for.
1128 static bool step_through(Node** np, uint instance_id, PhaseTransform* phase);
1129 };
1130
1131 //------------------------------MemBar-----------------------------------------
1132 // There are different flavors of Memory Barriers to match the Java Memory
1133 // Model. Monitor-enter and volatile-load act as Aquires: no following ref
1134 // can be moved to before them. We insert a MemBar-Acquire after a FastLock or
1135 // volatile-load. Monitor-exit and volatile-store act as Release: no
1136 // preceding ref can be moved to after them. We insert a MemBar-Release
1137 // before a FastUnlock or volatile-store. All volatiles need to be
1138 // serialized, so we follow all volatile-stores with a MemBar-Volatile to
1139 // separate it from any following volatile-load.
1140 class MemBarNode: public MultiNode {
1141 virtual uint hash() const ; // { return NO_HASH; }
1142 virtual uint cmp( const Node &n ) const ; // Always fail, except on self
1143
1144 virtual uint size_of() const { return sizeof(*this); }
1145 // Memory type this node is serializing. Usually either rawptr or bottom.
1146 const TypePtr* _adr_type;
1147
1148 // How is this membar related to a nearby memory access?
1149 enum {
1150 Standalone,
1151 TrailingLoad,
1152 TrailingStore,
1153 LeadingStore,
1154 TrailingLoadStore,
1155 LeadingLoadStore
1156 } _kind;
1157
1158 #ifdef ASSERT
1159 uint _pair_idx;
1160 #endif
1161
1162 public:
1163 enum {
1164 Precedent = TypeFunc::Parms // optional edge to force precedence
1165 };
1166 MemBarNode(Compile* C, int alias_idx, Node* precedent);
1167 virtual int Opcode() const = 0;
1168 virtual const class TypePtr *adr_type() const { return _adr_type; }
1169 virtual const Type* Value(PhaseGVN* phase) const;
1170 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
1171 virtual uint match_edge(uint idx) const { return 0; }
1172 virtual const Type *bottom_type() const { return TypeTuple::MEMBAR; }
1173 virtual Node *match( const ProjNode *proj, const Matcher *m );
1174 // Factory method. Builds a wide or narrow membar.
1175 // Optional 'precedent' becomes an extra edge if not null.
1176 static MemBarNode* make(Compile* C, int opcode,
1177 int alias_idx = Compile::AliasIdxBot,
1178 Node* precedent = NULL);
1179
1180 MemBarNode* trailing_membar() const;
1181 MemBarNode* leading_membar() const;
1182
1183 void set_trailing_load() { _kind = TrailingLoad; }
1184 bool trailing_load() const { return _kind == TrailingLoad; }
1185 bool trailing_store() const { return _kind == TrailingStore; }
1186 bool leading_store() const { return _kind == LeadingStore; }
1187 bool trailing_load_store() const { return _kind == TrailingLoadStore; }
1188 bool leading_load_store() const { return _kind == LeadingLoadStore; }
1189 bool trailing() const { return _kind == TrailingLoad || _kind == TrailingStore || _kind == TrailingLoadStore; }
1190 bool leading() const { return _kind == LeadingStore || _kind == LeadingLoadStore; }
1191 bool standalone() const { return _kind == Standalone; }
1192
1193 static void set_store_pair(MemBarNode* leading, MemBarNode* trailing);
1194 static void set_load_store_pair(MemBarNode* leading, MemBarNode* trailing);
1195
1196 void remove(PhaseIterGVN *igvn);
1197 };
1198
1199 // "Acquire" - no following ref can move before (but earlier refs can
1200 // follow, like an early Load stalled in cache). Requires multi-cpu
1201 // visibility. Inserted after a volatile load.
1202 class MemBarAcquireNode: public MemBarNode {
1203 public:
1204 MemBarAcquireNode(Compile* C, int alias_idx, Node* precedent)
1205 : MemBarNode(C, alias_idx, precedent) {}
1206 virtual int Opcode() const;
1207 };
1208
1209 // "Acquire" - no following ref can move before (but earlier refs can
1210 // follow, like an early Load stalled in cache). Requires multi-cpu
1211 // visibility. Inserted independ of any load, as required
1212 // for intrinsic Unsafe.loadFence().
1213 class LoadFenceNode: public MemBarNode {
1214 public:
1215 LoadFenceNode(Compile* C, int alias_idx, Node* precedent)
1216 : MemBarNode(C, alias_idx, precedent) {}
1217 virtual int Opcode() const;
1218 };
1219
1220 // "Release" - no earlier ref can move after (but later refs can move
1221 // up, like a speculative pipelined cache-hitting Load). Requires
1222 // multi-cpu visibility. Inserted before a volatile store.
1223 class MemBarReleaseNode: public MemBarNode {
1224 public:
1225 MemBarReleaseNode(Compile* C, int alias_idx, Node* precedent)
1226 : MemBarNode(C, alias_idx, precedent) {}
1227 virtual int Opcode() const;
1228 };
1229
1230 // "Release" - no earlier ref can move after (but later refs can move
1231 // up, like a speculative pipelined cache-hitting Load). Requires
1232 // multi-cpu visibility. Inserted independent of any store, as required
1233 // for intrinsic Unsafe.storeFence().
1234 class StoreFenceNode: public MemBarNode {
1235 public:
1236 StoreFenceNode(Compile* C, int alias_idx, Node* precedent)
1237 : MemBarNode(C, alias_idx, precedent) {}
1238 virtual int Opcode() const;
1239 };
1240
1241 // "Acquire" - no following ref can move before (but earlier refs can
1242 // follow, like an early Load stalled in cache). Requires multi-cpu
1243 // visibility. Inserted after a FastLock.
1244 class MemBarAcquireLockNode: public MemBarNode {
1245 public:
1246 MemBarAcquireLockNode(Compile* C, int alias_idx, Node* precedent)
1247 : MemBarNode(C, alias_idx, precedent) {}
1248 virtual int Opcode() const;
1249 };
1250
1251 // "Release" - no earlier ref can move after (but later refs can move
1252 // up, like a speculative pipelined cache-hitting Load). Requires
1253 // multi-cpu visibility. Inserted before a FastUnLock.
1254 class MemBarReleaseLockNode: public MemBarNode {
1255 public:
1256 MemBarReleaseLockNode(Compile* C, int alias_idx, Node* precedent)
1257 : MemBarNode(C, alias_idx, precedent) {}
1258 virtual int Opcode() const;
1259 };
1260
1261 class MemBarStoreStoreNode: public MemBarNode {
1262 public:
1263 MemBarStoreStoreNode(Compile* C, int alias_idx, Node* precedent)
1264 : MemBarNode(C, alias_idx, precedent) {
1265 init_class_id(Class_MemBarStoreStore);
1266 }
1267 virtual int Opcode() const;
1268 };
1269
1270 // Ordering between a volatile store and a following volatile load.
1271 // Requires multi-CPU visibility?
1272 class MemBarVolatileNode: public MemBarNode {
1273 public:
1274 MemBarVolatileNode(Compile* C, int alias_idx, Node* precedent)
1275 : MemBarNode(C, alias_idx, precedent) {}
1276 virtual int Opcode() const;
1277 };
1278
1279 // Ordering within the same CPU. Used to order unsafe memory references
1280 // inside the compiler when we lack alias info. Not needed "outside" the
1281 // compiler because the CPU does all the ordering for us.
1282 class MemBarCPUOrderNode: public MemBarNode {
1283 public:
1284 MemBarCPUOrderNode(Compile* C, int alias_idx, Node* precedent)
1285 : MemBarNode(C, alias_idx, precedent) {}
1286 virtual int Opcode() const;
1287 virtual uint ideal_reg() const { return 0; } // not matched in the AD file
1288 };
1289
1290 class OnSpinWaitNode: public MemBarNode {
1291 public:
1292 OnSpinWaitNode(Compile* C, int alias_idx, Node* precedent)
1293 : MemBarNode(C, alias_idx, precedent) {}
1294 virtual int Opcode() const;
1295 };
1296
1297 // Isolation of object setup after an AllocateNode and before next safepoint.
1298 // (See comment in memnode.cpp near InitializeNode::InitializeNode for semantics.)
1299 class InitializeNode: public MemBarNode {
1300 friend class AllocateNode;
1301
1302 enum {
1303 Incomplete = 0,
1304 Complete = 1,
1305 WithArraycopy = 2
1306 };
1307 int _is_complete;
1308
1309 bool _does_not_escape;
1310
1311 public:
1312 enum {
1313 Control = TypeFunc::Control,
1314 Memory = TypeFunc::Memory, // MergeMem for states affected by this op
1315 RawAddress = TypeFunc::Parms+0, // the newly-allocated raw address
1316 RawStores = TypeFunc::Parms+1 // zero or more stores (or TOP)
1317 };
1318
1319 InitializeNode(Compile* C, int adr_type, Node* rawoop);
1320 virtual int Opcode() const;
1321 virtual uint size_of() const { return sizeof(*this); }
1322 virtual uint ideal_reg() const { return 0; } // not matched in the AD file
1323 virtual const RegMask &in_RegMask(uint) const; // mask for RawAddress
1324
1325 // Manage incoming memory edges via a MergeMem on in(Memory):
1326 Node* memory(uint alias_idx);
1327
1328 // The raw memory edge coming directly from the Allocation.
1329 // The contents of this memory are *always* all-zero-bits.
1330 Node* zero_memory() { return memory(Compile::AliasIdxRaw); }
1331
1332 // Return the corresponding allocation for this initialization (or null if none).
1333 // (Note: Both InitializeNode::allocation and AllocateNode::initialization
1334 // are defined in graphKit.cpp, which sets up the bidirectional relation.)
1335 AllocateNode* allocation();
1336
1337 // Anything other than zeroing in this init?
1338 bool is_non_zero();
1339
1340 // An InitializeNode must completed before macro expansion is done.
1341 // Completion requires that the AllocateNode must be followed by
1342 // initialization of the new memory to zero, then to any initializers.
1343 bool is_complete() { return _is_complete != Incomplete; }
1344 bool is_complete_with_arraycopy() { return (_is_complete & WithArraycopy) != 0; }
1345
1346 // Mark complete. (Must not yet be complete.)
1347 void set_complete(PhaseGVN* phase);
1348 void set_complete_with_arraycopy() { _is_complete = Complete | WithArraycopy; }
1349
1350 bool does_not_escape() { return _does_not_escape; }
1351 void set_does_not_escape() { _does_not_escape = true; }
1352
1353 #ifdef ASSERT
1354 // ensure all non-degenerate stores are ordered and non-overlapping
1355 bool stores_are_sane(PhaseTransform* phase);
1356 #endif //ASSERT
1357
1358 // See if this store can be captured; return offset where it initializes.
1359 // Return 0 if the store cannot be moved (any sort of problem).
1360 intptr_t can_capture_store(StoreNode* st, PhaseTransform* phase, bool can_reshape);
1361
1362 // Capture another store; reformat it to write my internal raw memory.
1363 // Return the captured copy, else NULL if there is some sort of problem.
1364 Node* capture_store(StoreNode* st, intptr_t start, PhaseTransform* phase, bool can_reshape);
1365
1366 // Find captured store which corresponds to the range [start..start+size).
1367 // Return my own memory projection (meaning the initial zero bits)
1368 // if there is no such store. Return NULL if there is a problem.
1369 Node* find_captured_store(intptr_t start, int size_in_bytes, PhaseTransform* phase);
1370
1371 // Called when the associated AllocateNode is expanded into CFG.
1372 Node* complete_stores(Node* rawctl, Node* rawmem, Node* rawptr,
1373 intptr_t header_size, Node* size_in_bytes,
1374 PhaseGVN* phase);
1375
1376 private:
1377 void remove_extra_zeroes();
1378
1379 // Find out where a captured store should be placed (or already is placed).
1380 int captured_store_insertion_point(intptr_t start, int size_in_bytes,
1381 PhaseTransform* phase);
1382
1383 static intptr_t get_store_offset(Node* st, PhaseTransform* phase);
1384
1385 Node* make_raw_address(intptr_t offset, PhaseTransform* phase);
1386
1387 bool detect_init_independence(Node* n, int& count);
1388
1389 void coalesce_subword_stores(intptr_t header_size, Node* size_in_bytes,
1390 PhaseGVN* phase);
1391
1392 intptr_t find_next_fullword_store(uint i, PhaseGVN* phase);
1393 };
1394
1395 //------------------------------MergeMem---------------------------------------
1396 // (See comment in memnode.cpp near MergeMemNode::MergeMemNode for semantics.)
1397 class MergeMemNode: public Node {
1398 virtual uint hash() const ; // { return NO_HASH; }
1399 virtual uint cmp( const Node &n ) const ; // Always fail, except on self
1400 friend class MergeMemStream;
1401 MergeMemNode(Node* def); // clients use MergeMemNode::make
1402
1403 public:
1404 // If the input is a whole memory state, clone it with all its slices intact.
1405 // Otherwise, make a new memory state with just that base memory input.
1406 // In either case, the result is a newly created MergeMem.
1407 static MergeMemNode* make(Node* base_memory);
1408
1409 virtual int Opcode() const;
1410 virtual Node* Identity(PhaseGVN* phase);
1411 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
1412 virtual uint ideal_reg() const { return NotAMachineReg; }
1413 virtual uint match_edge(uint idx) const { return 0; }
1414 virtual const RegMask &out_RegMask() const;
1415 virtual const Type *bottom_type() const { return Type::MEMORY; }
1416 virtual const TypePtr *adr_type() const { return TypePtr::BOTTOM; }
1417 // sparse accessors
1418 // Fetch the previously stored "set_memory_at", or else the base memory.
1419 // (Caller should clone it if it is a phi-nest.)
1420 Node* memory_at(uint alias_idx) const;
1421 // set the memory, regardless of its previous value
1422 void set_memory_at(uint alias_idx, Node* n);
1423 // the "base" is the memory that provides the non-finite support
1424 Node* base_memory() const { return in(Compile::AliasIdxBot); }
1425 // warning: setting the base can implicitly set any of the other slices too
1426 void set_base_memory(Node* def);
1427 // sentinel value which denotes a copy of the base memory:
1428 Node* empty_memory() const { return in(Compile::AliasIdxTop); }
1429 static Node* make_empty_memory(); // where the sentinel comes from
1430 bool is_empty_memory(Node* n) const { assert((n == empty_memory()) == n->is_top(), "sanity"); return n->is_top(); }
1431 // hook for the iterator, to perform any necessary setup
1432 void iteration_setup(const MergeMemNode* other = NULL);
1433 // push sentinels until I am at least as long as the other (semantic no-op)
1434 void grow_to_match(const MergeMemNode* other);
1435 bool verify_sparse() const PRODUCT_RETURN0;
1436 #ifndef PRODUCT
1437 virtual void dump_spec(outputStream *st) const;
1438 #endif
1439 };
1440
1441 class MergeMemStream : public StackObj {
1442 private:
1443 MergeMemNode* _mm;
1444 const MergeMemNode* _mm2; // optional second guy, contributes non-empty iterations
1445 Node* _mm_base; // loop-invariant base memory of _mm
1446 int _idx;
1447 int _cnt;
1448 Node* _mem;
1449 Node* _mem2;
1450 int _cnt2;
1451
1452 void init(MergeMemNode* mm, const MergeMemNode* mm2 = NULL) {
1453 // subsume_node will break sparseness at times, whenever a memory slice
1454 // folds down to a copy of the base ("fat") memory. In such a case,
1455 // the raw edge will update to base, although it should be top.
1456 // This iterator will recognize either top or base_memory as an
1457 // "empty" slice. See is_empty, is_empty2, and next below.
1458 //
1459 // The sparseness property is repaired in MergeMemNode::Ideal.
1460 // As long as access to a MergeMem goes through this iterator
1461 // or the memory_at accessor, flaws in the sparseness will
1462 // never be observed.
1463 //
1464 // Also, iteration_setup repairs sparseness.
1465 assert(mm->verify_sparse(), "please, no dups of base");
1466 assert(mm2==NULL || mm2->verify_sparse(), "please, no dups of base");
1467
1468 _mm = mm;
1469 _mm_base = mm->base_memory();
1470 _mm2 = mm2;
1471 _cnt = mm->req();
1472 _idx = Compile::AliasIdxBot-1; // start at the base memory
1473 _mem = NULL;
1474 _mem2 = NULL;
1475 }
1476
1477 #ifdef ASSERT
1478 Node* check_memory() const {
1479 if (at_base_memory())
1480 return _mm->base_memory();
1481 else if ((uint)_idx < _mm->req() && !_mm->in(_idx)->is_top())
1482 return _mm->memory_at(_idx);
1483 else
1484 return _mm_base;
1485 }
1486 Node* check_memory2() const {
1487 return at_base_memory()? _mm2->base_memory(): _mm2->memory_at(_idx);
1488 }
1489 #endif
1490
1491 static bool match_memory(Node* mem, const MergeMemNode* mm, int idx) PRODUCT_RETURN0;
1492 void assert_synch() const {
1493 assert(!_mem || _idx >= _cnt || match_memory(_mem, _mm, _idx),
1494 "no side-effects except through the stream");
1495 }
1496
1497 public:
1498
1499 // expected usages:
1500 // for (MergeMemStream mms(mem->is_MergeMem()); next_non_empty(); ) { ... }
1501 // for (MergeMemStream mms(mem1, mem2); next_non_empty2(); ) { ... }
1502
1503 // iterate over one merge
1504 MergeMemStream(MergeMemNode* mm) {
1505 mm->iteration_setup();
1506 init(mm);
1507 debug_only(_cnt2 = 999);
1508 }
1509 // iterate in parallel over two merges
1510 // only iterates through non-empty elements of mm2
1511 MergeMemStream(MergeMemNode* mm, const MergeMemNode* mm2) {
1512 assert(mm2, "second argument must be a MergeMem also");
1513 ((MergeMemNode*)mm2)->iteration_setup(); // update hidden state
1514 mm->iteration_setup(mm2);
1515 init(mm, mm2);
1516 _cnt2 = mm2->req();
1517 }
1518 #ifdef ASSERT
1519 ~MergeMemStream() {
1520 assert_synch();
1521 }
1522 #endif
1523
1524 MergeMemNode* all_memory() const {
1525 return _mm;
1526 }
1527 Node* base_memory() const {
1528 assert(_mm_base == _mm->base_memory(), "no update to base memory, please");
1529 return _mm_base;
1530 }
1531 const MergeMemNode* all_memory2() const {
1532 assert(_mm2 != NULL, "");
1533 return _mm2;
1534 }
1535 bool at_base_memory() const {
1536 return _idx == Compile::AliasIdxBot;
1537 }
1538 int alias_idx() const {
1539 assert(_mem, "must call next 1st");
1540 return _idx;
1541 }
1542
1543 const TypePtr* adr_type() const {
1544 return Compile::current()->get_adr_type(alias_idx());
1545 }
1546
1547 const TypePtr* adr_type(Compile* C) const {
1548 return C->get_adr_type(alias_idx());
1549 }
1550 bool is_empty() const {
1551 assert(_mem, "must call next 1st");
1552 assert(_mem->is_top() == (_mem==_mm->empty_memory()), "correct sentinel");
1553 return _mem->is_top();
1554 }
1555 bool is_empty2() const {
1556 assert(_mem2, "must call next 1st");
1557 assert(_mem2->is_top() == (_mem2==_mm2->empty_memory()), "correct sentinel");
1558 return _mem2->is_top();
1559 }
1560 Node* memory() const {
1561 assert(!is_empty(), "must not be empty");
1562 assert_synch();
1563 return _mem;
1564 }
1565 // get the current memory, regardless of empty or non-empty status
1566 Node* force_memory() const {
1567 assert(!is_empty() || !at_base_memory(), "");
1568 // Use _mm_base to defend against updates to _mem->base_memory().
1569 Node *mem = _mem->is_top() ? _mm_base : _mem;
1570 assert(mem == check_memory(), "");
1571 return mem;
1572 }
1573 Node* memory2() const {
1574 assert(_mem2 == check_memory2(), "");
1575 return _mem2;
1576 }
1577 void set_memory(Node* mem) {
1578 if (at_base_memory()) {
1579 // Note that this does not change the invariant _mm_base.
1580 _mm->set_base_memory(mem);
1581 } else {
1582 _mm->set_memory_at(_idx, mem);
1583 }
1584 _mem = mem;
1585 assert_synch();
1586 }
1587
1588 // Recover from a side effect to the MergeMemNode.
1589 void set_memory() {
1590 _mem = _mm->in(_idx);
1591 }
1592
1593 bool next() { return next(false); }
1594 bool next2() { return next(true); }
1595
1596 bool next_non_empty() { return next_non_empty(false); }
1597 bool next_non_empty2() { return next_non_empty(true); }
1598 // next_non_empty2 can yield states where is_empty() is true
1599
1600 private:
1601 // find the next item, which might be empty
1602 bool next(bool have_mm2) {
1603 assert((_mm2 != NULL) == have_mm2, "use other next");
1604 assert_synch();
1605 if (++_idx < _cnt) {
1606 // Note: This iterator allows _mm to be non-sparse.
1607 // It behaves the same whether _mem is top or base_memory.
1608 _mem = _mm->in(_idx);
1609 if (have_mm2)
1610 _mem2 = _mm2->in((_idx < _cnt2) ? _idx : Compile::AliasIdxTop);
1611 return true;
1612 }
1613 return false;
1614 }
1615
1616 // find the next non-empty item
1617 bool next_non_empty(bool have_mm2) {
1618 while (next(have_mm2)) {
1619 if (!is_empty()) {
1620 // make sure _mem2 is filled in sensibly
1621 if (have_mm2 && _mem2->is_top()) _mem2 = _mm2->base_memory();
1622 return true;
1623 } else if (have_mm2 && !is_empty2()) {
1624 return true; // is_empty() == true
1625 }
1626 }
1627 return false;
1628 }
1629 };
1630
1631 //------------------------------Prefetch---------------------------------------
1632
1633 // Allocation prefetch which may fault, TLAB size have to be adjusted.
1634 class PrefetchAllocationNode : public Node {
1635 public:
1636 PrefetchAllocationNode(Node *mem, Node *adr) : Node(0,mem,adr) {}
1637 virtual int Opcode() const;
1638 virtual uint ideal_reg() const { return NotAMachineReg; }
1639 virtual uint match_edge(uint idx) const { return idx==2; }
1640 virtual const Type *bottom_type() const { return ( AllocatePrefetchStyle == 3 ) ? Type::MEMORY : Type::ABIO; }
1641 };
1642
1643 #endif // SHARE_VM_OPTO_MEMNODE_HPP