1 /*
2 * Copyright (c) 1997, 2019, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
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19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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23 */
24
25 #ifndef SHARE_OPTO_MEMNODE_HPP
26 #define SHARE_OPTO_MEMNODE_HPP
27
28 #include "opto/multnode.hpp"
29 #include "opto/node.hpp"
30 #include "opto/opcodes.hpp"
31 #include "opto/type.hpp"
32
33 // Portions of code courtesy of Clifford Click
34
35 class MultiNode;
36 class PhaseCCP;
37 class PhaseTransform;
38
39 //------------------------------MemNode----------------------------------------
40 // Load or Store, possibly throwing a NULL pointer exception
41 class MemNode : public Node {
42 private:
43 bool _unaligned_access; // Unaligned access from unsafe
44 bool _mismatched_access; // Mismatched access from unsafe: byte read in integer array for instance
45 bool _unsafe_access; // Access of unsafe origin.
46 protected:
47 #ifdef ASSERT
48 const TypePtr* _adr_type; // What kind of memory is being addressed?
49 #endif
50 virtual uint size_of() const;
51 public:
52 enum { Control, // When is it safe to do this load?
53 Memory, // Chunk of memory is being loaded from
54 Address, // Actually address, derived from base
55 ValueIn, // Value to store
56 OopStore // Preceeding oop store, only in StoreCM
57 };
58 typedef enum { unordered = 0,
59 acquire, // Load has to acquire or be succeeded by MemBarAcquire.
60 release, // Store has to release or be preceded by MemBarRelease.
61 seqcst, // LoadStore has to have both acquire and release semantics.
62 unset // The memory ordering is not set (used for testing)
63 } MemOrd;
64 protected:
65 MemNode( Node *c0, Node *c1, Node *c2, const TypePtr* at )
66 : Node(c0,c1,c2 ), _unaligned_access(false), _mismatched_access(false), _unsafe_access(false) {
67 init_class_id(Class_Mem);
68 debug_only(_adr_type=at; adr_type();)
69 }
70 MemNode( Node *c0, Node *c1, Node *c2, const TypePtr* at, Node *c3 )
71 : Node(c0,c1,c2,c3), _unaligned_access(false), _mismatched_access(false), _unsafe_access(false) {
72 init_class_id(Class_Mem);
73 debug_only(_adr_type=at; adr_type();)
74 }
75 MemNode( Node *c0, Node *c1, Node *c2, const TypePtr* at, Node *c3, Node *c4)
76 : Node(c0,c1,c2,c3,c4), _unaligned_access(false), _mismatched_access(false), _unsafe_access(false) {
77 init_class_id(Class_Mem);
78 debug_only(_adr_type=at; adr_type();)
79 }
80
81 virtual Node* find_previous_arraycopy(PhaseTransform* phase, Node* ld_alloc, Node*& mem, bool can_see_stored_value) const { return NULL; }
82 static bool check_if_adr_maybe_raw(Node* adr);
83
84 public:
85 // Helpers for the optimizer. Documented in memnode.cpp.
86 static bool detect_ptr_independence(Node* p1, AllocateNode* a1,
87 Node* p2, AllocateNode* a2,
88 PhaseTransform* phase);
89 static bool adr_phi_is_loop_invariant(Node* adr_phi, Node* cast);
90
91 static Node *optimize_simple_memory_chain(Node *mchain, const TypeOopPtr *t_oop, Node *load, PhaseGVN *phase);
92 static Node *optimize_memory_chain(Node *mchain, const TypePtr *t_adr, Node *load, PhaseGVN *phase);
93 // This one should probably be a phase-specific function:
94 static bool all_controls_dominate(Node* dom, Node* sub);
95
96 virtual const class TypePtr *adr_type() const; // returns bottom_type of address
97
98 // Shared code for Ideal methods:
99 Node *Ideal_common(PhaseGVN *phase, bool can_reshape); // Return -1 for short-circuit NULL.
100
101 // Helper function for adr_type() implementations.
102 static const TypePtr* calculate_adr_type(const Type* t, const TypePtr* cross_check = NULL);
103
104 // Raw access function, to allow copying of adr_type efficiently in
105 // product builds and retain the debug info for debug builds.
106 const TypePtr *raw_adr_type() const {
107 #ifdef ASSERT
108 return _adr_type;
109 #else
110 return 0;
111 #endif
112 }
113
114 // Map a load or store opcode to its corresponding store opcode.
115 // (Return -1 if unknown.)
116 virtual int store_Opcode() const { return -1; }
117
118 // What is the type of the value in memory? (T_VOID mean "unspecified".)
119 virtual BasicType memory_type() const = 0;
120 virtual int memory_size() const {
121 #ifdef ASSERT
122 return type2aelembytes(memory_type(), true);
123 #else
124 return type2aelembytes(memory_type());
125 #endif
126 }
127
128 // Search through memory states which precede this node (load or store).
129 // Look for an exact match for the address, with no intervening
130 // aliased stores.
131 Node* find_previous_store(PhaseTransform* phase);
132
133 // Can this node (load or store) accurately see a stored value in
134 // the given memory state? (The state may or may not be in(Memory).)
135 Node* can_see_stored_value(Node* st, PhaseTransform* phase) const;
136
137 void set_unaligned_access() { _unaligned_access = true; }
138 bool is_unaligned_access() const { return _unaligned_access; }
139 void set_mismatched_access() { _mismatched_access = true; }
140 bool is_mismatched_access() const { return _mismatched_access; }
141 void set_unsafe_access() { _unsafe_access = true; }
142 bool is_unsafe_access() const { return _unsafe_access; }
143
144 #ifndef PRODUCT
145 static void dump_adr_type(const Node* mem, const TypePtr* adr_type, outputStream *st);
146 virtual void dump_spec(outputStream *st) const;
147 #endif
148 };
149
150 //------------------------------LoadNode---------------------------------------
151 // Load value; requires Memory and Address
152 class LoadNode : public MemNode {
153 public:
154 // Some loads (from unsafe) should be pinned: they don't depend only
155 // on the dominating test. The field _control_dependency below records
156 // whether that node depends only on the dominating test.
157 // Methods used to build LoadNodes pass an argument of type enum
158 // ControlDependency instead of a boolean because those methods
159 // typically have multiple boolean parameters with default values:
160 // passing the wrong boolean to one of these parameters by mistake
161 // goes easily unnoticed. Using an enum, the compiler can check that
162 // the type of a value and the type of the parameter match.
163 enum ControlDependency {
164 Pinned,
165 DependsOnlyOnTest
166 };
167 private:
168 // LoadNode::hash() doesn't take the _control_dependency field
169 // into account: If the graph already has a non-pinned LoadNode and
170 // we add a pinned LoadNode with the same inputs, it's safe for GVN
171 // to replace the pinned LoadNode with the non-pinned LoadNode,
172 // otherwise it wouldn't be safe to have a non pinned LoadNode with
173 // those inputs in the first place. If the graph already has a
174 // pinned LoadNode and we add a non pinned LoadNode with the same
175 // inputs, it's safe (but suboptimal) for GVN to replace the
176 // non-pinned LoadNode by the pinned LoadNode.
177 ControlDependency _control_dependency;
178
179 // On platforms with weak memory ordering (e.g., PPC, Ia64) we distinguish
180 // loads that can be reordered, and such requiring acquire semantics to
181 // adhere to the Java specification. The required behaviour is stored in
182 // this field.
183 const MemOrd _mo;
184
185 protected:
186 virtual bool cmp(const Node &n) const;
187 virtual uint size_of() const; // Size is bigger
188 // Should LoadNode::Ideal() attempt to remove control edges?
189 virtual bool can_remove_control() const;
190 const Type* const _type; // What kind of value is loaded?
191
192 virtual Node* find_previous_arraycopy(PhaseTransform* phase, Node* ld_alloc, Node*& mem, bool can_see_stored_value) const;
193 public:
194
195 LoadNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const Type *rt, MemOrd mo, ControlDependency control_dependency)
196 : MemNode(c,mem,adr,at), _control_dependency(control_dependency), _mo(mo), _type(rt) {
197 init_class_id(Class_Load);
198 }
199 inline bool is_unordered() const { return !is_acquire(); }
200 inline bool is_acquire() const {
201 assert(_mo == unordered || _mo == acquire, "unexpected");
202 return _mo == acquire;
203 }
204 inline bool is_unsigned() const {
205 int lop = Opcode();
206 return (lop == Op_LoadUB) || (lop == Op_LoadUS);
207 }
208
209 // Polymorphic factory method:
210 static Node* make(PhaseGVN& gvn, Node *c, Node *mem, Node *adr,
211 const TypePtr* at, const Type *rt, BasicType bt,
212 MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest,
213 bool unaligned = false, bool mismatched = false, bool unsafe = false);
214
215 virtual uint hash() const; // Check the type
216
217 // Handle algebraic identities here. If we have an identity, return the Node
218 // we are equivalent to. We look for Load of a Store.
219 virtual Node* Identity(PhaseGVN* phase);
220
221 // If the load is from Field memory and the pointer is non-null, it might be possible to
222 // zero out the control input.
223 // If the offset is constant and the base is an object allocation,
224 // try to hook me up to the exact initializing store.
225 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
226
227 // Split instance field load through Phi.
228 Node* split_through_phi(PhaseGVN *phase);
229
230 // Recover original value from boxed values
231 Node *eliminate_autobox(PhaseGVN *phase);
232
233 // Compute a new Type for this node. Basically we just do the pre-check,
234 // then call the virtual add() to set the type.
235 virtual const Type* Value(PhaseGVN* phase) const;
236
237 // Common methods for LoadKlass and LoadNKlass nodes.
238 const Type* klass_value_common(PhaseGVN* phase) const;
239 Node* klass_identity_common(PhaseGVN* phase);
240
241 virtual uint ideal_reg() const;
242 virtual const Type *bottom_type() const;
243 // Following method is copied from TypeNode:
244 void set_type(const Type* t) {
245 assert(t != NULL, "sanity");
246 debug_only(uint check_hash = (VerifyHashTableKeys && _hash_lock) ? hash() : NO_HASH);
247 *(const Type**)&_type = t; // cast away const-ness
248 // If this node is in the hash table, make sure it doesn't need a rehash.
249 assert(check_hash == NO_HASH || check_hash == hash(), "type change must preserve hash code");
250 }
251 const Type* type() const { assert(_type != NULL, "sanity"); return _type; };
252
253 // Do not match memory edge
254 virtual uint match_edge(uint idx) const;
255
256 // Map a load opcode to its corresponding store opcode.
257 virtual int store_Opcode() const = 0;
258
259 // Check if the load's memory input is a Phi node with the same control.
260 bool is_instance_field_load_with_local_phi(Node* ctrl);
261
262 Node* convert_to_unsigned_load(PhaseGVN& gvn);
263 Node* convert_to_signed_load(PhaseGVN& gvn);
264
265 #ifndef PRODUCT
266 virtual void dump_spec(outputStream *st) const;
267 #endif
268 #ifdef ASSERT
269 // Helper function to allow a raw load without control edge for some cases
270 static bool is_immutable_value(Node* adr);
271 #endif
272 protected:
273 const Type* load_array_final_field(const TypeKlassPtr *tkls,
274 ciKlass* klass) const;
275
276 Node* can_see_arraycopy_value(Node* st, PhaseGVN* phase) const;
277
278 // depends_only_on_test is almost always true, and needs to be almost always
279 // true to enable key hoisting & commoning optimizations. However, for the
280 // special case of RawPtr loads from TLS top & end, and other loads performed by
281 // GC barriers, the control edge carries the dependence preventing hoisting past
282 // a Safepoint instead of the memory edge. (An unfortunate consequence of having
283 // Safepoints not set Raw Memory; itself an unfortunate consequence of having Nodes
284 // which produce results (new raw memory state) inside of loops preventing all
285 // manner of other optimizations). Basically, it's ugly but so is the alternative.
286 // See comment in macro.cpp, around line 125 expand_allocate_common().
287 virtual bool depends_only_on_test() const {
288 return adr_type() != TypeRawPtr::BOTTOM && _control_dependency == DependsOnlyOnTest;
289 }
290 };
291
292 //------------------------------LoadBNode--------------------------------------
293 // Load a byte (8bits signed) from memory
294 class LoadBNode : public LoadNode {
295 public:
296 LoadBNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeInt *ti, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
297 : LoadNode(c, mem, adr, at, ti, mo, control_dependency) {}
298 virtual int Opcode() const;
299 virtual uint ideal_reg() const { return Op_RegI; }
300 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
301 virtual const Type* Value(PhaseGVN* phase) const;
302 virtual int store_Opcode() const { return Op_StoreB; }
303 virtual BasicType memory_type() const { return T_BYTE; }
304 };
305
306 //------------------------------LoadUBNode-------------------------------------
307 // Load a unsigned byte (8bits unsigned) from memory
308 class LoadUBNode : public LoadNode {
309 public:
310 LoadUBNode(Node* c, Node* mem, Node* adr, const TypePtr* at, const TypeInt* ti, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
311 : LoadNode(c, mem, adr, at, ti, mo, control_dependency) {}
312 virtual int Opcode() const;
313 virtual uint ideal_reg() const { return Op_RegI; }
314 virtual Node* Ideal(PhaseGVN *phase, bool can_reshape);
315 virtual const Type* Value(PhaseGVN* phase) const;
316 virtual int store_Opcode() const { return Op_StoreB; }
317 virtual BasicType memory_type() const { return T_BYTE; }
318 };
319
320 //------------------------------LoadUSNode-------------------------------------
321 // Load an unsigned short/char (16bits unsigned) from memory
322 class LoadUSNode : public LoadNode {
323 public:
324 LoadUSNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeInt *ti, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
325 : LoadNode(c, mem, adr, at, ti, mo, control_dependency) {}
326 virtual int Opcode() const;
327 virtual uint ideal_reg() const { return Op_RegI; }
328 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
329 virtual const Type* Value(PhaseGVN* phase) const;
330 virtual int store_Opcode() const { return Op_StoreC; }
331 virtual BasicType memory_type() const { return T_CHAR; }
332 };
333
334 //------------------------------LoadSNode--------------------------------------
335 // Load a short (16bits signed) from memory
336 class LoadSNode : public LoadNode {
337 public:
338 LoadSNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeInt *ti, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
339 : LoadNode(c, mem, adr, at, ti, mo, control_dependency) {}
340 virtual int Opcode() const;
341 virtual uint ideal_reg() const { return Op_RegI; }
342 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
343 virtual const Type* Value(PhaseGVN* phase) const;
344 virtual int store_Opcode() const { return Op_StoreC; }
345 virtual BasicType memory_type() const { return T_SHORT; }
346 };
347
348 //------------------------------LoadINode--------------------------------------
349 // Load an integer from memory
350 class LoadINode : public LoadNode {
351 public:
352 LoadINode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeInt *ti, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
353 : LoadNode(c, mem, adr, at, ti, mo, control_dependency) {}
354 virtual int Opcode() const;
355 virtual uint ideal_reg() const { return Op_RegI; }
356 virtual int store_Opcode() const { return Op_StoreI; }
357 virtual BasicType memory_type() const { return T_INT; }
358 };
359
360 //------------------------------LoadRangeNode----------------------------------
361 // Load an array length from the array
362 class LoadRangeNode : public LoadINode {
363 public:
364 LoadRangeNode(Node *c, Node *mem, Node *adr, const TypeInt *ti = TypeInt::POS)
365 : LoadINode(c, mem, adr, TypeAryPtr::RANGE, ti, MemNode::unordered) {}
366 virtual int Opcode() const;
367 virtual const Type* Value(PhaseGVN* phase) const;
368 virtual Node* Identity(PhaseGVN* phase);
369 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
370 };
371
372 //------------------------------LoadLNode--------------------------------------
373 // Load a long from memory
374 class LoadLNode : public LoadNode {
375 virtual uint hash() const { return LoadNode::hash() + _require_atomic_access; }
376 virtual bool cmp( const Node &n ) const {
377 return _require_atomic_access == ((LoadLNode&)n)._require_atomic_access
378 && LoadNode::cmp(n);
379 }
380 virtual uint size_of() const { return sizeof(*this); }
381 const bool _require_atomic_access; // is piecewise load forbidden?
382
383 public:
384 LoadLNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeLong *tl,
385 MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest, bool require_atomic_access = false)
386 : LoadNode(c, mem, adr, at, tl, mo, control_dependency), _require_atomic_access(require_atomic_access) {}
387 virtual int Opcode() const;
388 virtual uint ideal_reg() const { return Op_RegL; }
389 virtual int store_Opcode() const { return Op_StoreL; }
390 virtual BasicType memory_type() const { return T_LONG; }
391 bool require_atomic_access() const { return _require_atomic_access; }
392 static LoadLNode* make_atomic(Node* ctl, Node* mem, Node* adr, const TypePtr* adr_type,
393 const Type* rt, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest,
394 bool unaligned = false, bool mismatched = false, bool unsafe = false);
395 #ifndef PRODUCT
396 virtual void dump_spec(outputStream *st) const {
397 LoadNode::dump_spec(st);
398 if (_require_atomic_access) st->print(" Atomic!");
399 }
400 #endif
401 };
402
403 //------------------------------LoadL_unalignedNode----------------------------
404 // Load a long from unaligned memory
405 class LoadL_unalignedNode : public LoadLNode {
406 public:
407 LoadL_unalignedNode(Node *c, Node *mem, Node *adr, const TypePtr* at, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
408 : LoadLNode(c, mem, adr, at, TypeLong::LONG, mo, control_dependency) {}
409 virtual int Opcode() const;
410 };
411
412 //------------------------------LoadFNode--------------------------------------
413 // Load a float (64 bits) from memory
414 class LoadFNode : public LoadNode {
415 public:
416 LoadFNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const Type *t, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
417 : LoadNode(c, mem, adr, at, t, mo, control_dependency) {}
418 virtual int Opcode() const;
419 virtual uint ideal_reg() const { return Op_RegF; }
420 virtual int store_Opcode() const { return Op_StoreF; }
421 virtual BasicType memory_type() const { return T_FLOAT; }
422 };
423
424 //------------------------------LoadDNode--------------------------------------
425 // Load a double (64 bits) from memory
426 class LoadDNode : public LoadNode {
427 virtual uint hash() const { return LoadNode::hash() + _require_atomic_access; }
428 virtual bool cmp( const Node &n ) const {
429 return _require_atomic_access == ((LoadDNode&)n)._require_atomic_access
430 && LoadNode::cmp(n);
431 }
432 virtual uint size_of() const { return sizeof(*this); }
433 const bool _require_atomic_access; // is piecewise load forbidden?
434
435 public:
436 LoadDNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const Type *t,
437 MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest, bool require_atomic_access = false)
438 : LoadNode(c, mem, adr, at, t, mo, control_dependency), _require_atomic_access(require_atomic_access) {}
439 virtual int Opcode() const;
440 virtual uint ideal_reg() const { return Op_RegD; }
441 virtual int store_Opcode() const { return Op_StoreD; }
442 virtual BasicType memory_type() const { return T_DOUBLE; }
443 bool require_atomic_access() const { return _require_atomic_access; }
444 static LoadDNode* make_atomic(Node* ctl, Node* mem, Node* adr, const TypePtr* adr_type,
445 const Type* rt, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest,
446 bool unaligned = false, bool mismatched = false, bool unsafe = false);
447 #ifndef PRODUCT
448 virtual void dump_spec(outputStream *st) const {
449 LoadNode::dump_spec(st);
450 if (_require_atomic_access) st->print(" Atomic!");
451 }
452 #endif
453 };
454
455 //------------------------------LoadD_unalignedNode----------------------------
456 // Load a double from unaligned memory
457 class LoadD_unalignedNode : public LoadDNode {
458 public:
459 LoadD_unalignedNode(Node *c, Node *mem, Node *adr, const TypePtr* at, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
460 : LoadDNode(c, mem, adr, at, Type::DOUBLE, mo, control_dependency) {}
461 virtual int Opcode() const;
462 };
463
464 //------------------------------LoadPNode--------------------------------------
465 // Load a pointer from memory (either object or array)
466 class LoadPNode : public LoadNode {
467 public:
468 LoadPNode(Node *c, Node *mem, Node *adr, const TypePtr *at, const TypePtr* t, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
469 : LoadNode(c, mem, adr, at, t, mo, control_dependency) {}
470 virtual int Opcode() const;
471 virtual uint ideal_reg() const { return Op_RegP; }
472 virtual int store_Opcode() const { return Op_StoreP; }
473 virtual BasicType memory_type() const { return T_ADDRESS; }
474 };
475
476
477 //------------------------------LoadNNode--------------------------------------
478 // Load a narrow oop from memory (either object or array)
479 class LoadNNode : public LoadNode {
480 public:
481 LoadNNode(Node *c, Node *mem, Node *adr, const TypePtr *at, const Type* t, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
482 : LoadNode(c, mem, adr, at, t, mo, control_dependency) {}
483 virtual int Opcode() const;
484 virtual uint ideal_reg() const { return Op_RegN; }
485 virtual int store_Opcode() const { return Op_StoreN; }
486 virtual BasicType memory_type() const { return T_NARROWOOP; }
487 };
488
489 //------------------------------LoadKlassNode----------------------------------
490 // Load a Klass from an object
491 class LoadKlassNode : public LoadPNode {
492 protected:
493 // In most cases, LoadKlassNode does not have the control input set. If the control
494 // input is set, it must not be removed (by LoadNode::Ideal()).
495 virtual bool can_remove_control() const;
496 public:
497 LoadKlassNode(Node *c, Node *mem, Node *adr, const TypePtr *at, const TypeKlassPtr *tk, MemOrd mo)
498 : LoadPNode(c, mem, adr, at, tk, mo) {}
499 virtual int Opcode() const;
500 virtual const Type* Value(PhaseGVN* phase) const;
501 virtual Node* Identity(PhaseGVN* phase);
502 virtual bool depends_only_on_test() const { return true; }
503
504 // Polymorphic factory method:
505 static Node* make(PhaseGVN& gvn, Node* ctl, Node* mem, Node* adr, const TypePtr* at,
506 const TypeKlassPtr* tk = TypeKlassPtr::OBJECT);
507 };
508
509 //------------------------------LoadNKlassNode---------------------------------
510 // Load a narrow Klass from an object.
511 class LoadNKlassNode : public LoadNNode {
512 public:
513 LoadNKlassNode(Node *c, Node *mem, Node *adr, const TypePtr *at, const TypeNarrowKlass *tk, MemOrd mo)
514 : LoadNNode(c, mem, adr, at, tk, mo) {}
515 virtual int Opcode() const;
516 virtual uint ideal_reg() const { return Op_RegN; }
517 virtual int store_Opcode() const { return Op_StoreNKlass; }
518 virtual BasicType memory_type() const { return T_NARROWKLASS; }
519
520 virtual const Type* Value(PhaseGVN* phase) const;
521 virtual Node* Identity(PhaseGVN* phase);
522 virtual bool depends_only_on_test() const { return true; }
523 };
524
525
526 //------------------------------StoreNode--------------------------------------
527 // Store value; requires Store, Address and Value
528 class StoreNode : public MemNode {
529 private:
530 // On platforms with weak memory ordering (e.g., PPC, Ia64) we distinguish
531 // stores that can be reordered, and such requiring release semantics to
532 // adhere to the Java specification. The required behaviour is stored in
533 // this field.
534 const MemOrd _mo;
535 // Needed for proper cloning.
536 virtual uint size_of() const { return sizeof(*this); }
537 protected:
538 virtual bool cmp( const Node &n ) const;
539 virtual bool depends_only_on_test() const { return false; }
540
541 Node *Ideal_masked_input (PhaseGVN *phase, uint mask);
542 Node *Ideal_sign_extended_input(PhaseGVN *phase, int num_bits);
543
544 public:
545 // We must ensure that stores of object references will be visible
546 // only after the object's initialization. So the callers of this
547 // procedure must indicate that the store requires `release'
548 // semantics, if the stored value is an object reference that might
549 // point to a new object and may become externally visible.
550 StoreNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
551 : MemNode(c, mem, adr, at, val), _mo(mo) {
552 init_class_id(Class_Store);
553 }
554 StoreNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, Node *oop_store, MemOrd mo)
555 : MemNode(c, mem, adr, at, val, oop_store), _mo(mo) {
556 init_class_id(Class_Store);
557 }
558
559 inline bool is_unordered() const { return !is_release(); }
560 inline bool is_release() const {
561 assert((_mo == unordered || _mo == release), "unexpected");
562 return _mo == release;
563 }
564
565 // Conservatively release stores of object references in order to
566 // ensure visibility of object initialization.
567 static inline MemOrd release_if_reference(const BasicType t) {
568 #ifdef AARCH64
569 // AArch64 doesn't need a release store here because object
570 // initialization contains the necessary barriers.
571 return unordered;
572 #else
573 const MemOrd mo = (t == T_ARRAY ||
574 t == T_ADDRESS || // Might be the address of an object reference (`boxing').
575 t == T_OBJECT) ? release : unordered;
576 return mo;
577 #endif
578 }
579
580 // Polymorphic factory method
581 //
582 // We must ensure that stores of object references will be visible
583 // only after the object's initialization. So the callers of this
584 // procedure must indicate that the store requires `release'
585 // semantics, if the stored value is an object reference that might
586 // point to a new object and may become externally visible.
587 static StoreNode* make(PhaseGVN& gvn, Node *c, Node *mem, Node *adr,
588 const TypePtr* at, Node *val, BasicType bt, MemOrd mo);
589
590 virtual uint hash() const; // Check the type
591
592 // If the store is to Field memory and the pointer is non-null, we can
593 // zero out the control input.
594 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
595
596 // Compute a new Type for this node. Basically we just do the pre-check,
597 // then call the virtual add() to set the type.
598 virtual const Type* Value(PhaseGVN* phase) const;
599
600 // Check for identity function on memory (Load then Store at same address)
601 virtual Node* Identity(PhaseGVN* phase);
602
603 // Do not match memory edge
604 virtual uint match_edge(uint idx) const;
605
606 virtual const Type *bottom_type() const; // returns Type::MEMORY
607
608 // Map a store opcode to its corresponding own opcode, trivially.
609 virtual int store_Opcode() const { return Opcode(); }
610
611 // have all possible loads of the value stored been optimized away?
612 bool value_never_loaded(PhaseTransform *phase) const;
613
614 MemBarNode* trailing_membar() const;
615 };
616
617 //------------------------------StoreBNode-------------------------------------
618 // Store byte to memory
619 class StoreBNode : public StoreNode {
620 public:
621 StoreBNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
622 : StoreNode(c, mem, adr, at, val, mo) {}
623 virtual int Opcode() const;
624 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
625 virtual BasicType memory_type() const { return T_BYTE; }
626 };
627
628 //------------------------------StoreCNode-------------------------------------
629 // Store char/short to memory
630 class StoreCNode : public StoreNode {
631 public:
632 StoreCNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
633 : StoreNode(c, mem, adr, at, val, mo) {}
634 virtual int Opcode() const;
635 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
636 virtual BasicType memory_type() const { return T_CHAR; }
637 };
638
639 //------------------------------StoreINode-------------------------------------
640 // Store int to memory
641 class StoreINode : public StoreNode {
642 public:
643 StoreINode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
644 : StoreNode(c, mem, adr, at, val, mo) {}
645 virtual int Opcode() const;
646 virtual BasicType memory_type() const { return T_INT; }
647 };
648
649 //------------------------------StoreLNode-------------------------------------
650 // Store long to memory
651 class StoreLNode : public StoreNode {
652 virtual uint hash() const { return StoreNode::hash() + _require_atomic_access; }
653 virtual bool cmp( const Node &n ) const {
654 return _require_atomic_access == ((StoreLNode&)n)._require_atomic_access
655 && StoreNode::cmp(n);
656 }
657 virtual uint size_of() const { return sizeof(*this); }
658 const bool _require_atomic_access; // is piecewise store forbidden?
659
660 public:
661 StoreLNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo, bool require_atomic_access = false)
662 : StoreNode(c, mem, adr, at, val, mo), _require_atomic_access(require_atomic_access) {}
663 virtual int Opcode() const;
664 virtual BasicType memory_type() const { return T_LONG; }
665 bool require_atomic_access() const { return _require_atomic_access; }
666 static StoreLNode* make_atomic(Node* ctl, Node* mem, Node* adr, const TypePtr* adr_type, Node* val, MemOrd mo);
667 #ifndef PRODUCT
668 virtual void dump_spec(outputStream *st) const {
669 StoreNode::dump_spec(st);
670 if (_require_atomic_access) st->print(" Atomic!");
671 }
672 #endif
673 };
674
675 //------------------------------StoreFNode-------------------------------------
676 // Store float to memory
677 class StoreFNode : public StoreNode {
678 public:
679 StoreFNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
680 : StoreNode(c, mem, adr, at, val, mo) {}
681 virtual int Opcode() const;
682 virtual BasicType memory_type() const { return T_FLOAT; }
683 };
684
685 //------------------------------StoreDNode-------------------------------------
686 // Store double to memory
687 class StoreDNode : public StoreNode {
688 virtual uint hash() const { return StoreNode::hash() + _require_atomic_access; }
689 virtual bool cmp( const Node &n ) const {
690 return _require_atomic_access == ((StoreDNode&)n)._require_atomic_access
691 && StoreNode::cmp(n);
692 }
693 virtual uint size_of() const { return sizeof(*this); }
694 const bool _require_atomic_access; // is piecewise store forbidden?
695 public:
696 StoreDNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val,
697 MemOrd mo, bool require_atomic_access = false)
698 : StoreNode(c, mem, adr, at, val, mo), _require_atomic_access(require_atomic_access) {}
699 virtual int Opcode() const;
700 virtual BasicType memory_type() const { return T_DOUBLE; }
701 bool require_atomic_access() const { return _require_atomic_access; }
702 static StoreDNode* make_atomic(Node* ctl, Node* mem, Node* adr, const TypePtr* adr_type, Node* val, MemOrd mo);
703 #ifndef PRODUCT
704 virtual void dump_spec(outputStream *st) const {
705 StoreNode::dump_spec(st);
706 if (_require_atomic_access) st->print(" Atomic!");
707 }
708 #endif
709
710 };
711
712 //------------------------------StorePNode-------------------------------------
713 // Store pointer to memory
714 class StorePNode : public StoreNode {
715 public:
716 StorePNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
717 : StoreNode(c, mem, adr, at, val, mo) {}
718 virtual int Opcode() const;
719 virtual BasicType memory_type() const { return T_ADDRESS; }
720 };
721
722 //------------------------------StoreNNode-------------------------------------
723 // Store narrow oop to memory
724 class StoreNNode : public StoreNode {
725 public:
726 StoreNNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
727 : StoreNode(c, mem, adr, at, val, mo) {}
728 virtual int Opcode() const;
729 virtual BasicType memory_type() const { return T_NARROWOOP; }
730 };
731
732 //------------------------------StoreNKlassNode--------------------------------------
733 // Store narrow klass to memory
734 class StoreNKlassNode : public StoreNNode {
735 public:
736 StoreNKlassNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
737 : StoreNNode(c, mem, adr, at, val, mo) {}
738 virtual int Opcode() const;
739 virtual BasicType memory_type() const { return T_NARROWKLASS; }
740 };
741
742 //------------------------------StoreCMNode-----------------------------------
743 // Store card-mark byte to memory for CM
744 // The last StoreCM before a SafePoint must be preserved and occur after its "oop" store
745 // Preceeding equivalent StoreCMs may be eliminated.
746 class StoreCMNode : public StoreNode {
747 private:
748 virtual uint hash() const { return StoreNode::hash() + _oop_alias_idx; }
749 virtual bool cmp( const Node &n ) const {
750 return _oop_alias_idx == ((StoreCMNode&)n)._oop_alias_idx
751 && StoreNode::cmp(n);
752 }
753 virtual uint size_of() const { return sizeof(*this); }
754 int _oop_alias_idx; // The alias_idx of OopStore
755
756 public:
757 StoreCMNode( Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, Node *oop_store, int oop_alias_idx ) :
758 StoreNode(c, mem, adr, at, val, oop_store, MemNode::release),
759 _oop_alias_idx(oop_alias_idx) {
760 assert(_oop_alias_idx >= Compile::AliasIdxRaw ||
761 _oop_alias_idx == Compile::AliasIdxBot && Compile::current()->AliasLevel() == 0,
762 "bad oop alias idx");
763 }
764 virtual int Opcode() const;
765 virtual Node* Identity(PhaseGVN* phase);
766 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
767 virtual const Type* Value(PhaseGVN* phase) const;
768 virtual BasicType memory_type() const { return T_VOID; } // unspecific
769 int oop_alias_idx() const { return _oop_alias_idx; }
770 };
771
772 //------------------------------LoadPLockedNode---------------------------------
773 // Load-locked a pointer from memory (either object or array).
774 // On Sparc & Intel this is implemented as a normal pointer load.
775 // On PowerPC and friends it's a real load-locked.
776 class LoadPLockedNode : public LoadPNode {
777 public:
778 LoadPLockedNode(Node *c, Node *mem, Node *adr, MemOrd mo)
779 : LoadPNode(c, mem, adr, TypeRawPtr::BOTTOM, TypeRawPtr::BOTTOM, mo) {}
780 virtual int Opcode() const;
781 virtual int store_Opcode() const { return Op_StorePConditional; }
782 virtual bool depends_only_on_test() const { return true; }
783 };
784
785 //------------------------------SCMemProjNode---------------------------------------
786 // This class defines a projection of the memory state of a store conditional node.
787 // These nodes return a value, but also update memory.
788 class SCMemProjNode : public ProjNode {
789 public:
790 enum {SCMEMPROJCON = (uint)-2};
791 SCMemProjNode( Node *src) : ProjNode( src, SCMEMPROJCON) { }
792 virtual int Opcode() const;
793 virtual bool is_CFG() const { return false; }
794 virtual const Type *bottom_type() const {return Type::MEMORY;}
795 virtual const TypePtr *adr_type() const {
796 Node* ctrl = in(0);
797 if (ctrl == NULL) return NULL; // node is dead
798 return ctrl->in(MemNode::Memory)->adr_type();
799 }
800 virtual uint ideal_reg() const { return 0;} // memory projections don't have a register
801 virtual const Type* Value(PhaseGVN* phase) const;
802 #ifndef PRODUCT
803 virtual void dump_spec(outputStream *st) const {};
804 #endif
805 };
806
807 //------------------------------LoadStoreNode---------------------------
808 // Note: is_Mem() method returns 'true' for this class.
809 class LoadStoreNode : public Node {
810 private:
811 const Type* const _type; // What kind of value is loaded?
812 const TypePtr* _adr_type; // What kind of memory is being addressed?
813 virtual uint size_of() const; // Size is bigger
814 public:
815 LoadStoreNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at, const Type* rt, uint required );
816 virtual bool depends_only_on_test() const { return false; }
817 virtual uint match_edge(uint idx) const { return idx == MemNode::Address || idx == MemNode::ValueIn; }
818
819 virtual const Type *bottom_type() const { return _type; }
820 virtual uint ideal_reg() const;
821 virtual const class TypePtr *adr_type() const { return _adr_type; } // returns bottom_type of address
822
823 bool result_not_used() const;
824 MemBarNode* trailing_membar() const;
825 };
826
827 class LoadStoreConditionalNode : public LoadStoreNode {
828 public:
829 enum {
830 ExpectedIn = MemNode::ValueIn+1 // One more input than MemNode
831 };
832 LoadStoreConditionalNode(Node *c, Node *mem, Node *adr, Node *val, Node *ex);
833 };
834
835 //------------------------------StorePConditionalNode---------------------------
836 // Conditionally store pointer to memory, if no change since prior
837 // load-locked. Sets flags for success or failure of the store.
838 class StorePConditionalNode : public LoadStoreConditionalNode {
839 public:
840 StorePConditionalNode( Node *c, Node *mem, Node *adr, Node *val, Node *ll ) : LoadStoreConditionalNode(c, mem, adr, val, ll) { }
841 virtual int Opcode() const;
842 // Produces flags
843 virtual uint ideal_reg() const { return Op_RegFlags; }
844 };
845
846 //------------------------------StoreIConditionalNode---------------------------
847 // Conditionally store int to memory, if no change since prior
848 // load-locked. Sets flags for success or failure of the store.
849 class StoreIConditionalNode : public LoadStoreConditionalNode {
850 public:
851 StoreIConditionalNode( Node *c, Node *mem, Node *adr, Node *val, Node *ii ) : LoadStoreConditionalNode(c, mem, adr, val, ii) { }
852 virtual int Opcode() const;
853 // Produces flags
854 virtual uint ideal_reg() const { return Op_RegFlags; }
855 };
856
857 //------------------------------StoreLConditionalNode---------------------------
858 // Conditionally store long to memory, if no change since prior
859 // load-locked. Sets flags for success or failure of the store.
860 class StoreLConditionalNode : public LoadStoreConditionalNode {
861 public:
862 StoreLConditionalNode( Node *c, Node *mem, Node *adr, Node *val, Node *ll ) : LoadStoreConditionalNode(c, mem, adr, val, ll) { }
863 virtual int Opcode() const;
864 // Produces flags
865 virtual uint ideal_reg() const { return Op_RegFlags; }
866 };
867
868 class CompareAndSwapNode : public LoadStoreConditionalNode {
869 private:
870 const MemNode::MemOrd _mem_ord;
871 public:
872 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) {}
873 MemNode::MemOrd order() const {
874 return _mem_ord;
875 }
876 };
877
878 class CompareAndExchangeNode : public LoadStoreNode {
879 private:
880 const MemNode::MemOrd _mem_ord;
881 public:
882 enum {
883 ExpectedIn = MemNode::ValueIn+1 // One more input than MemNode
884 };
885 CompareAndExchangeNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord, const TypePtr* at, const Type* t) :
886 LoadStoreNode(c, mem, adr, val, at, t, 5), _mem_ord(mem_ord) {
887 init_req(ExpectedIn, ex );
888 }
889
890 MemNode::MemOrd order() const {
891 return _mem_ord;
892 }
893 };
894
895 //------------------------------CompareAndSwapBNode---------------------------
896 class CompareAndSwapBNode : public CompareAndSwapNode {
897 public:
898 CompareAndSwapBNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
899 virtual int Opcode() const;
900 };
901
902 //------------------------------CompareAndSwapSNode---------------------------
903 class CompareAndSwapSNode : public CompareAndSwapNode {
904 public:
905 CompareAndSwapSNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
906 virtual int Opcode() const;
907 };
908
909 //------------------------------CompareAndSwapINode---------------------------
910 class CompareAndSwapINode : public CompareAndSwapNode {
911 public:
912 CompareAndSwapINode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
913 virtual int Opcode() const;
914 };
915
916 //------------------------------CompareAndSwapLNode---------------------------
917 class CompareAndSwapLNode : public CompareAndSwapNode {
918 public:
919 CompareAndSwapLNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
920 virtual int Opcode() const;
921 };
922
923 //------------------------------CompareAndSwapPNode---------------------------
924 class CompareAndSwapPNode : public CompareAndSwapNode {
925 public:
926 CompareAndSwapPNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
927 virtual int Opcode() const;
928 };
929
930 //------------------------------CompareAndSwapNNode---------------------------
931 class CompareAndSwapNNode : public CompareAndSwapNode {
932 public:
933 CompareAndSwapNNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
934 virtual int Opcode() const;
935 };
936
937 //------------------------------WeakCompareAndSwapBNode---------------------------
938 class WeakCompareAndSwapBNode : public CompareAndSwapNode {
939 public:
940 WeakCompareAndSwapBNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
941 virtual int Opcode() const;
942 };
943
944 //------------------------------WeakCompareAndSwapSNode---------------------------
945 class WeakCompareAndSwapSNode : public CompareAndSwapNode {
946 public:
947 WeakCompareAndSwapSNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
948 virtual int Opcode() const;
949 };
950
951 //------------------------------WeakCompareAndSwapINode---------------------------
952 class WeakCompareAndSwapINode : public CompareAndSwapNode {
953 public:
954 WeakCompareAndSwapINode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
955 virtual int Opcode() const;
956 };
957
958 //------------------------------WeakCompareAndSwapLNode---------------------------
959 class WeakCompareAndSwapLNode : public CompareAndSwapNode {
960 public:
961 WeakCompareAndSwapLNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
962 virtual int Opcode() const;
963 };
964
965 //------------------------------WeakCompareAndSwapPNode---------------------------
966 class WeakCompareAndSwapPNode : public CompareAndSwapNode {
967 public:
968 WeakCompareAndSwapPNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
969 virtual int Opcode() const;
970 };
971
972 //------------------------------WeakCompareAndSwapNNode---------------------------
973 class WeakCompareAndSwapNNode : public CompareAndSwapNode {
974 public:
975 WeakCompareAndSwapNNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
976 virtual int Opcode() const;
977 };
978
979 //------------------------------CompareAndExchangeBNode---------------------------
980 class CompareAndExchangeBNode : public CompareAndExchangeNode {
981 public:
982 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) { }
983 virtual int Opcode() const;
984 };
985
986
987 //------------------------------CompareAndExchangeSNode---------------------------
988 class CompareAndExchangeSNode : public CompareAndExchangeNode {
989 public:
990 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) { }
991 virtual int Opcode() const;
992 };
993
994 //------------------------------CompareAndExchangeLNode---------------------------
995 class CompareAndExchangeLNode : public CompareAndExchangeNode {
996 public:
997 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) { }
998 virtual int Opcode() const;
999 };
1000
1001
1002 //------------------------------CompareAndExchangeINode---------------------------
1003 class CompareAndExchangeINode : public CompareAndExchangeNode {
1004 public:
1005 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) { }
1006 virtual int Opcode() const;
1007 };
1008
1009
1010 //------------------------------CompareAndExchangePNode---------------------------
1011 class CompareAndExchangePNode : public CompareAndExchangeNode {
1012 public:
1013 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) { }
1014 virtual int Opcode() const;
1015 };
1016
1017 //------------------------------CompareAndExchangeNNode---------------------------
1018 class CompareAndExchangeNNode : public CompareAndExchangeNode {
1019 public:
1020 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) { }
1021 virtual int Opcode() const;
1022 };
1023
1024 //------------------------------GetAndAddBNode---------------------------
1025 class GetAndAddBNode : public LoadStoreNode {
1026 public:
1027 GetAndAddBNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeInt::BYTE, 4) { }
1028 virtual int Opcode() const;
1029 };
1030
1031 //------------------------------GetAndAddSNode---------------------------
1032 class GetAndAddSNode : public LoadStoreNode {
1033 public:
1034 GetAndAddSNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeInt::SHORT, 4) { }
1035 virtual int Opcode() const;
1036 };
1037
1038 //------------------------------GetAndAddINode---------------------------
1039 class GetAndAddINode : public LoadStoreNode {
1040 public:
1041 GetAndAddINode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeInt::INT, 4) { }
1042 virtual int Opcode() const;
1043 };
1044
1045 //------------------------------GetAndAddLNode---------------------------
1046 class GetAndAddLNode : public LoadStoreNode {
1047 public:
1048 GetAndAddLNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeLong::LONG, 4) { }
1049 virtual int Opcode() const;
1050 };
1051
1052 //------------------------------GetAndSetBNode---------------------------
1053 class GetAndSetBNode : public LoadStoreNode {
1054 public:
1055 GetAndSetBNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeInt::BYTE, 4) { }
1056 virtual int Opcode() const;
1057 };
1058
1059 //------------------------------GetAndSetSNode---------------------------
1060 class GetAndSetSNode : public LoadStoreNode {
1061 public:
1062 GetAndSetSNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeInt::SHORT, 4) { }
1063 virtual int Opcode() const;
1064 };
1065
1066 //------------------------------GetAndSetINode---------------------------
1067 class GetAndSetINode : public LoadStoreNode {
1068 public:
1069 GetAndSetINode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeInt::INT, 4) { }
1070 virtual int Opcode() const;
1071 };
1072
1073 //------------------------------GetAndSetLNode---------------------------
1074 class GetAndSetLNode : public LoadStoreNode {
1075 public:
1076 GetAndSetLNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeLong::LONG, 4) { }
1077 virtual int Opcode() const;
1078 };
1079
1080 //------------------------------GetAndSetPNode---------------------------
1081 class GetAndSetPNode : public LoadStoreNode {
1082 public:
1083 GetAndSetPNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at, const Type* t ) : LoadStoreNode(c, mem, adr, val, at, t, 4) { }
1084 virtual int Opcode() const;
1085 };
1086
1087 //------------------------------GetAndSetNNode---------------------------
1088 class GetAndSetNNode : public LoadStoreNode {
1089 public:
1090 GetAndSetNNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at, const Type* t ) : LoadStoreNode(c, mem, adr, val, at, t, 4) { }
1091 virtual int Opcode() const;
1092 };
1093
1094 //------------------------------ClearArray-------------------------------------
1095 class ClearArrayNode: public Node {
1096 private:
1097 bool _is_large;
1098 bool _word_copy_only;
1099 public:
1100 ClearArrayNode( Node *ctrl, Node *arymem, Node *word_cnt, Node *base, Node* val, bool is_large)
1101 : Node(ctrl, arymem, word_cnt, base, val), _is_large(is_large),
1102 _word_copy_only(val->bottom_type()->isa_long() && (!val->bottom_type()->is_long()->is_con() || val->bottom_type()->is_long()->get_con() != 0)) {
1103 init_class_id(Class_ClearArray);
1104 }
1105 virtual int Opcode() const;
1106 virtual const Type *bottom_type() const { return Type::MEMORY; }
1107 // ClearArray modifies array elements, and so affects only the
1108 // array memory addressed by the bottom_type of its base address.
1109 virtual const class TypePtr *adr_type() const;
1110 virtual Node* Identity(PhaseGVN* phase);
1111 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
1112 virtual uint match_edge(uint idx) const;
1113 bool is_large() const { return _is_large; }
1114 bool word_copy_only() const { return _word_copy_only; }
1115
1116 // Clear the given area of an object or array.
1117 // The start offset must always be aligned mod BytesPerInt.
1118 // The end offset must always be aligned mod BytesPerLong.
1119 // Return the new memory.
1120 static Node* clear_memory(Node* control, Node* mem, Node* dest,
1121 Node* val,
1122 Node* raw_val,
1123 intptr_t start_offset,
1124 intptr_t end_offset,
1125 PhaseGVN* phase);
1126 static Node* clear_memory(Node* control, Node* mem, Node* dest,
1127 Node* val,
1128 Node* raw_val,
1129 intptr_t start_offset,
1130 Node* end_offset,
1131 PhaseGVN* phase);
1132 static Node* clear_memory(Node* control, Node* mem, Node* dest,
1133 Node* raw_val,
1134 Node* start_offset,
1135 Node* end_offset,
1136 PhaseGVN* phase);
1137 // Return allocation input memory edge if it is different instance
1138 // or itself if it is the one we are looking for.
1139 static bool step_through(Node** np, uint instance_id, PhaseTransform* phase);
1140 };
1141
1142 //------------------------------MemBar-----------------------------------------
1143 // There are different flavors of Memory Barriers to match the Java Memory
1144 // Model. Monitor-enter and volatile-load act as Aquires: no following ref
1145 // can be moved to before them. We insert a MemBar-Acquire after a FastLock or
1146 // volatile-load. Monitor-exit and volatile-store act as Release: no
1147 // preceding ref can be moved to after them. We insert a MemBar-Release
1148 // before a FastUnlock or volatile-store. All volatiles need to be
1149 // serialized, so we follow all volatile-stores with a MemBar-Volatile to
1150 // separate it from any following volatile-load.
1151 class MemBarNode: public MultiNode {
1152 virtual uint hash() const ; // { return NO_HASH; }
1153 virtual bool cmp( const Node &n ) const ; // Always fail, except on self
1154
1155 virtual uint size_of() const { return sizeof(*this); }
1156 // Memory type this node is serializing. Usually either rawptr or bottom.
1157 const TypePtr* _adr_type;
1158
1159 // How is this membar related to a nearby memory access?
1160 enum {
1161 Standalone,
1162 TrailingLoad,
1163 TrailingStore,
1164 LeadingStore,
1165 TrailingLoadStore,
1166 LeadingLoadStore
1167 } _kind;
1168
1169 #ifdef ASSERT
1170 uint _pair_idx;
1171 #endif
1172
1173 public:
1174 enum {
1175 Precedent = TypeFunc::Parms // optional edge to force precedence
1176 };
1177 MemBarNode(Compile* C, int alias_idx, Node* precedent);
1178 virtual int Opcode() const = 0;
1179 virtual const class TypePtr *adr_type() const { return _adr_type; }
1180 virtual const Type* Value(PhaseGVN* phase) const;
1181 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
1182 virtual uint match_edge(uint idx) const { return 0; }
1183 virtual const Type *bottom_type() const { return TypeTuple::MEMBAR; }
1184 virtual Node *match(const ProjNode *proj, const Matcher *m, const RegMask* mask);
1185 // Factory method. Builds a wide or narrow membar.
1186 // Optional 'precedent' becomes an extra edge if not null.
1187 static MemBarNode* make(Compile* C, int opcode,
1188 int alias_idx = Compile::AliasIdxBot,
1189 Node* precedent = NULL);
1190
1191 MemBarNode* trailing_membar() const;
1192 MemBarNode* leading_membar() const;
1193
1194 void set_trailing_load() { _kind = TrailingLoad; }
1195 bool trailing_load() const { return _kind == TrailingLoad; }
1196 bool trailing_store() const { return _kind == TrailingStore; }
1197 bool leading_store() const { return _kind == LeadingStore; }
1198 bool trailing_load_store() const { return _kind == TrailingLoadStore; }
1199 bool leading_load_store() const { return _kind == LeadingLoadStore; }
1200 bool trailing() const { return _kind == TrailingLoad || _kind == TrailingStore || _kind == TrailingLoadStore; }
1201 bool leading() const { return _kind == LeadingStore || _kind == LeadingLoadStore; }
1202 bool standalone() const { return _kind == Standalone; }
1203
1204 static void set_store_pair(MemBarNode* leading, MemBarNode* trailing);
1205 static void set_load_store_pair(MemBarNode* leading, MemBarNode* trailing);
1206
1207 void remove(PhaseIterGVN *igvn);
1208 };
1209
1210 // "Acquire" - no following ref can move before (but earlier refs can
1211 // follow, like an early Load stalled in cache). Requires multi-cpu
1212 // visibility. Inserted after a volatile load.
1213 class MemBarAcquireNode: public MemBarNode {
1214 public:
1215 MemBarAcquireNode(Compile* C, int alias_idx, Node* precedent)
1216 : MemBarNode(C, alias_idx, precedent) {}
1217 virtual int Opcode() const;
1218 };
1219
1220 // "Acquire" - no following ref can move before (but earlier refs can
1221 // follow, like an early Load stalled in cache). Requires multi-cpu
1222 // visibility. Inserted independ of any load, as required
1223 // for intrinsic Unsafe.loadFence().
1224 class LoadFenceNode: public MemBarNode {
1225 public:
1226 LoadFenceNode(Compile* C, int alias_idx, Node* precedent)
1227 : MemBarNode(C, alias_idx, precedent) {}
1228 virtual int Opcode() const;
1229 };
1230
1231 // "Release" - no earlier ref can move after (but later refs can move
1232 // up, like a speculative pipelined cache-hitting Load). Requires
1233 // multi-cpu visibility. Inserted before a volatile store.
1234 class MemBarReleaseNode: public MemBarNode {
1235 public:
1236 MemBarReleaseNode(Compile* C, int alias_idx, Node* precedent)
1237 : MemBarNode(C, alias_idx, precedent) {}
1238 virtual int Opcode() const;
1239 };
1240
1241 // "Release" - no earlier ref can move after (but later refs can move
1242 // up, like a speculative pipelined cache-hitting Load). Requires
1243 // multi-cpu visibility. Inserted independent of any store, as required
1244 // for intrinsic Unsafe.storeFence().
1245 class StoreFenceNode: public MemBarNode {
1246 public:
1247 StoreFenceNode(Compile* C, int alias_idx, Node* precedent)
1248 : MemBarNode(C, alias_idx, precedent) {}
1249 virtual int Opcode() const;
1250 };
1251
1252 // "Acquire" - no following ref can move before (but earlier refs can
1253 // follow, like an early Load stalled in cache). Requires multi-cpu
1254 // visibility. Inserted after a FastLock.
1255 class MemBarAcquireLockNode: public MemBarNode {
1256 public:
1257 MemBarAcquireLockNode(Compile* C, int alias_idx, Node* precedent)
1258 : MemBarNode(C, alias_idx, precedent) {}
1259 virtual int Opcode() const;
1260 };
1261
1262 // "Release" - no earlier ref can move after (but later refs can move
1263 // up, like a speculative pipelined cache-hitting Load). Requires
1264 // multi-cpu visibility. Inserted before a FastUnLock.
1265 class MemBarReleaseLockNode: public MemBarNode {
1266 public:
1267 MemBarReleaseLockNode(Compile* C, int alias_idx, Node* precedent)
1268 : MemBarNode(C, alias_idx, precedent) {}
1269 virtual int Opcode() const;
1270 };
1271
1272 class MemBarStoreStoreNode: public MemBarNode {
1273 public:
1274 MemBarStoreStoreNode(Compile* C, int alias_idx, Node* precedent)
1275 : MemBarNode(C, alias_idx, precedent) {
1276 init_class_id(Class_MemBarStoreStore);
1277 }
1278 virtual int Opcode() const;
1279 };
1280
1281 // Ordering between a volatile store and a following volatile load.
1282 // Requires multi-CPU visibility?
1283 class MemBarVolatileNode: public MemBarNode {
1284 public:
1285 MemBarVolatileNode(Compile* C, int alias_idx, Node* precedent)
1286 : MemBarNode(C, alias_idx, precedent) {}
1287 virtual int Opcode() const;
1288 };
1289
1290 // Ordering within the same CPU. Used to order unsafe memory references
1291 // inside the compiler when we lack alias info. Not needed "outside" the
1292 // compiler because the CPU does all the ordering for us.
1293 class MemBarCPUOrderNode: public MemBarNode {
1294 public:
1295 MemBarCPUOrderNode(Compile* C, int alias_idx, Node* precedent)
1296 : MemBarNode(C, alias_idx, precedent) {}
1297 virtual int Opcode() const;
1298 virtual uint ideal_reg() const { return 0; } // not matched in the AD file
1299 };
1300
1301 class OnSpinWaitNode: public MemBarNode {
1302 public:
1303 OnSpinWaitNode(Compile* C, int alias_idx, Node* precedent)
1304 : MemBarNode(C, alias_idx, precedent) {}
1305 virtual int Opcode() const;
1306 };
1307
1308 // Isolation of object setup after an AllocateNode and before next safepoint.
1309 // (See comment in memnode.cpp near InitializeNode::InitializeNode for semantics.)
1310 class InitializeNode: public MemBarNode {
1311 friend class AllocateNode;
1312
1313 enum {
1314 Incomplete = 0,
1315 Complete = 1,
1316 WithArraycopy = 2,
1317 };
1318 int _is_complete;
1319
1320 bool _does_not_escape;
1321
1322 public:
1323 enum {
1324 Control = TypeFunc::Control,
1325 Memory = TypeFunc::Memory, // MergeMem for states affected by this op
1326 RawAddress = TypeFunc::Parms+0, // the newly-allocated raw address
1327 RawStores = TypeFunc::Parms+1 // zero or more stores (or TOP)
1328 };
1329
1330 InitializeNode(Compile* C, int adr_type, Node* rawoop);
1331 virtual int Opcode() const;
1332 virtual uint size_of() const { return sizeof(*this); }
1333 virtual uint ideal_reg() const { return 0; } // not matched in the AD file
1334 virtual const RegMask &in_RegMask(uint) const; // mask for RawAddress
1335
1336 // Manage incoming memory edges via a MergeMem on in(Memory):
1337 Node* memory(uint alias_idx);
1338
1339 // The raw memory edge coming directly from the Allocation.
1340 // The contents of this memory are *always* all-zero-bits.
1341 Node* zero_memory() { return memory(Compile::AliasIdxRaw); }
1342
1343 // Return the corresponding allocation for this initialization (or null if none).
1344 // (Note: Both InitializeNode::allocation and AllocateNode::initialization
1345 // are defined in graphKit.cpp, which sets up the bidirectional relation.)
1346 AllocateNode* allocation();
1347
1348 // Anything other than zeroing in this init?
1349 bool is_non_zero();
1350
1351 // An InitializeNode must completed before macro expansion is done.
1352 // Completion requires that the AllocateNode must be followed by
1353 // initialization of the new memory to zero, then to any initializers.
1354 bool is_complete() { return _is_complete != Incomplete; }
1355 bool is_complete_with_arraycopy() { return (_is_complete & WithArraycopy) != 0; }
1356
1357 // Mark complete. (Must not yet be complete.)
1358 void set_complete(PhaseGVN* phase);
1359 void set_complete_with_arraycopy() { _is_complete = Complete | WithArraycopy; }
1360
1361 bool does_not_escape() { return _does_not_escape; }
1362 void set_does_not_escape() { _does_not_escape = true; }
1363
1364 #ifdef ASSERT
1365 // ensure all non-degenerate stores are ordered and non-overlapping
1366 bool stores_are_sane(PhaseTransform* phase);
1367 #endif //ASSERT
1368
1369 // See if this store can be captured; return offset where it initializes.
1370 // Return 0 if the store cannot be moved (any sort of problem).
1371 intptr_t can_capture_store(StoreNode* st, PhaseTransform* phase, bool can_reshape);
1372
1373 // Capture another store; reformat it to write my internal raw memory.
1374 // Return the captured copy, else NULL if there is some sort of problem.
1375 Node* capture_store(StoreNode* st, intptr_t start, PhaseTransform* phase, bool can_reshape);
1376
1377 // Find captured store which corresponds to the range [start..start+size).
1378 // Return my own memory projection (meaning the initial zero bits)
1379 // if there is no such store. Return NULL if there is a problem.
1380 Node* find_captured_store(intptr_t start, int size_in_bytes, PhaseTransform* phase);
1381
1382 // Called when the associated AllocateNode is expanded into CFG.
1383 Node* complete_stores(Node* rawctl, Node* rawmem, Node* rawptr,
1384 intptr_t header_size, Node* size_in_bytes,
1385 PhaseGVN* phase);
1386
1387 private:
1388 void remove_extra_zeroes();
1389
1390 // Find out where a captured store should be placed (or already is placed).
1391 int captured_store_insertion_point(intptr_t start, int size_in_bytes,
1392 PhaseTransform* phase);
1393
1394 static intptr_t get_store_offset(Node* st, PhaseTransform* phase);
1395
1396 Node* make_raw_address(intptr_t offset, PhaseTransform* phase);
1397
1398 bool detect_init_independence(Node* n, int& count);
1399
1400 void coalesce_subword_stores(intptr_t header_size, Node* size_in_bytes,
1401 PhaseGVN* phase);
1402
1403 intptr_t find_next_fullword_store(uint i, PhaseGVN* phase);
1404 };
1405
1406 //------------------------------MergeMem---------------------------------------
1407 // (See comment in memnode.cpp near MergeMemNode::MergeMemNode for semantics.)
1408 class MergeMemNode: public Node {
1409 virtual uint hash() const ; // { return NO_HASH; }
1410 virtual bool cmp( const Node &n ) const ; // Always fail, except on self
1411 friend class MergeMemStream;
1412 MergeMemNode(Node* def); // clients use MergeMemNode::make
1413
1414 public:
1415 // If the input is a whole memory state, clone it with all its slices intact.
1416 // Otherwise, make a new memory state with just that base memory input.
1417 // In either case, the result is a newly created MergeMem.
1418 static MergeMemNode* make(Node* base_memory);
1419
1420 virtual int Opcode() const;
1421 virtual Node* Identity(PhaseGVN* phase);
1422 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
1423 virtual uint ideal_reg() const { return NotAMachineReg; }
1424 virtual uint match_edge(uint idx) const { return 0; }
1425 virtual const RegMask &out_RegMask() const;
1426 virtual const Type *bottom_type() const { return Type::MEMORY; }
1427 virtual const TypePtr *adr_type() const { return TypePtr::BOTTOM; }
1428 // sparse accessors
1429 // Fetch the previously stored "set_memory_at", or else the base memory.
1430 // (Caller should clone it if it is a phi-nest.)
1431 Node* memory_at(uint alias_idx) const;
1432 // set the memory, regardless of its previous value
1433 void set_memory_at(uint alias_idx, Node* n);
1434 // the "base" is the memory that provides the non-finite support
1435 Node* base_memory() const { return in(Compile::AliasIdxBot); }
1436 // warning: setting the base can implicitly set any of the other slices too
1437 void set_base_memory(Node* def);
1438 // sentinel value which denotes a copy of the base memory:
1439 Node* empty_memory() const { return in(Compile::AliasIdxTop); }
1440 static Node* make_empty_memory(); // where the sentinel comes from
1441 bool is_empty_memory(Node* n) const { assert((n == empty_memory()) == n->is_top(), "sanity"); return n->is_top(); }
1442 // hook for the iterator, to perform any necessary setup
1443 void iteration_setup(const MergeMemNode* other = NULL);
1444 // push sentinels until I am at least as long as the other (semantic no-op)
1445 void grow_to_match(const MergeMemNode* other);
1446 bool verify_sparse() const PRODUCT_RETURN0;
1447 #ifndef PRODUCT
1448 virtual void dump_spec(outputStream *st) const;
1449 #endif
1450 };
1451
1452 class MergeMemStream : public StackObj {
1453 private:
1454 MergeMemNode* _mm;
1455 const MergeMemNode* _mm2; // optional second guy, contributes non-empty iterations
1456 Node* _mm_base; // loop-invariant base memory of _mm
1457 int _idx;
1458 int _cnt;
1459 Node* _mem;
1460 Node* _mem2;
1461 int _cnt2;
1462
1463 void init(MergeMemNode* mm, const MergeMemNode* mm2 = NULL) {
1464 // subsume_node will break sparseness at times, whenever a memory slice
1465 // folds down to a copy of the base ("fat") memory. In such a case,
1466 // the raw edge will update to base, although it should be top.
1467 // This iterator will recognize either top or base_memory as an
1468 // "empty" slice. See is_empty, is_empty2, and next below.
1469 //
1470 // The sparseness property is repaired in MergeMemNode::Ideal.
1471 // As long as access to a MergeMem goes through this iterator
1472 // or the memory_at accessor, flaws in the sparseness will
1473 // never be observed.
1474 //
1475 // Also, iteration_setup repairs sparseness.
1476 assert(mm->verify_sparse(), "please, no dups of base");
1477 assert(mm2==NULL || mm2->verify_sparse(), "please, no dups of base");
1478
1479 _mm = mm;
1480 _mm_base = mm->base_memory();
1481 _mm2 = mm2;
1482 _cnt = mm->req();
1483 _idx = Compile::AliasIdxBot-1; // start at the base memory
1484 _mem = NULL;
1485 _mem2 = NULL;
1486 }
1487
1488 #ifdef ASSERT
1489 Node* check_memory() const {
1490 if (at_base_memory())
1491 return _mm->base_memory();
1492 else if ((uint)_idx < _mm->req() && !_mm->in(_idx)->is_top())
1493 return _mm->memory_at(_idx);
1494 else
1495 return _mm_base;
1496 }
1497 Node* check_memory2() const {
1498 return at_base_memory()? _mm2->base_memory(): _mm2->memory_at(_idx);
1499 }
1500 #endif
1501
1502 static bool match_memory(Node* mem, const MergeMemNode* mm, int idx) PRODUCT_RETURN0;
1503 void assert_synch() const {
1504 assert(!_mem || _idx >= _cnt || match_memory(_mem, _mm, _idx),
1505 "no side-effects except through the stream");
1506 }
1507
1508 public:
1509
1510 // expected usages:
1511 // for (MergeMemStream mms(mem->is_MergeMem()); next_non_empty(); ) { ... }
1512 // for (MergeMemStream mms(mem1, mem2); next_non_empty2(); ) { ... }
1513
1514 // iterate over one merge
1515 MergeMemStream(MergeMemNode* mm) {
1516 mm->iteration_setup();
1517 init(mm);
1518 debug_only(_cnt2 = 999);
1519 }
1520 // iterate in parallel over two merges
1521 // only iterates through non-empty elements of mm2
1522 MergeMemStream(MergeMemNode* mm, const MergeMemNode* mm2) {
1523 assert(mm2, "second argument must be a MergeMem also");
1524 ((MergeMemNode*)mm2)->iteration_setup(); // update hidden state
1525 mm->iteration_setup(mm2);
1526 init(mm, mm2);
1527 _cnt2 = mm2->req();
1528 }
1529 #ifdef ASSERT
1530 ~MergeMemStream() {
1531 assert_synch();
1532 }
1533 #endif
1534
1535 MergeMemNode* all_memory() const {
1536 return _mm;
1537 }
1538 Node* base_memory() const {
1539 assert(_mm_base == _mm->base_memory(), "no update to base memory, please");
1540 return _mm_base;
1541 }
1542 const MergeMemNode* all_memory2() const {
1543 assert(_mm2 != NULL, "");
1544 return _mm2;
1545 }
1546 bool at_base_memory() const {
1547 return _idx == Compile::AliasIdxBot;
1548 }
1549 int alias_idx() const {
1550 assert(_mem, "must call next 1st");
1551 return _idx;
1552 }
1553
1554 const TypePtr* adr_type() const {
1555 return Compile::current()->get_adr_type(alias_idx());
1556 }
1557
1558 const TypePtr* adr_type(Compile* C) const {
1559 return C->get_adr_type(alias_idx());
1560 }
1561 bool is_empty() const {
1562 assert(_mem, "must call next 1st");
1563 assert(_mem->is_top() == (_mem==_mm->empty_memory()), "correct sentinel");
1564 return _mem->is_top();
1565 }
1566 bool is_empty2() const {
1567 assert(_mem2, "must call next 1st");
1568 assert(_mem2->is_top() == (_mem2==_mm2->empty_memory()), "correct sentinel");
1569 return _mem2->is_top();
1570 }
1571 Node* memory() const {
1572 assert(!is_empty(), "must not be empty");
1573 assert_synch();
1574 return _mem;
1575 }
1576 // get the current memory, regardless of empty or non-empty status
1577 Node* force_memory() const {
1578 assert(!is_empty() || !at_base_memory(), "");
1579 // Use _mm_base to defend against updates to _mem->base_memory().
1580 Node *mem = _mem->is_top() ? _mm_base : _mem;
1581 assert(mem == check_memory(), "");
1582 return mem;
1583 }
1584 Node* memory2() const {
1585 assert(_mem2 == check_memory2(), "");
1586 return _mem2;
1587 }
1588 void set_memory(Node* mem) {
1589 if (at_base_memory()) {
1590 // Note that this does not change the invariant _mm_base.
1591 _mm->set_base_memory(mem);
1592 } else {
1593 _mm->set_memory_at(_idx, mem);
1594 }
1595 _mem = mem;
1596 assert_synch();
1597 }
1598
1599 // Recover from a side effect to the MergeMemNode.
1600 void set_memory() {
1601 _mem = _mm->in(_idx);
1602 }
1603
1604 bool next() { return next(false); }
1605 bool next2() { return next(true); }
1606
1607 bool next_non_empty() { return next_non_empty(false); }
1608 bool next_non_empty2() { return next_non_empty(true); }
1609 // next_non_empty2 can yield states where is_empty() is true
1610
1611 private:
1612 // find the next item, which might be empty
1613 bool next(bool have_mm2) {
1614 assert((_mm2 != NULL) == have_mm2, "use other next");
1615 assert_synch();
1616 if (++_idx < _cnt) {
1617 // Note: This iterator allows _mm to be non-sparse.
1618 // It behaves the same whether _mem is top or base_memory.
1619 _mem = _mm->in(_idx);
1620 if (have_mm2)
1621 _mem2 = _mm2->in((_idx < _cnt2) ? _idx : Compile::AliasIdxTop);
1622 return true;
1623 }
1624 return false;
1625 }
1626
1627 // find the next non-empty item
1628 bool next_non_empty(bool have_mm2) {
1629 while (next(have_mm2)) {
1630 if (!is_empty()) {
1631 // make sure _mem2 is filled in sensibly
1632 if (have_mm2 && _mem2->is_top()) _mem2 = _mm2->base_memory();
1633 return true;
1634 } else if (have_mm2 && !is_empty2()) {
1635 return true; // is_empty() == true
1636 }
1637 }
1638 return false;
1639 }
1640 };
1641
1642 //------------------------------Prefetch---------------------------------------
1643
1644 // Allocation prefetch which may fault, TLAB size have to be adjusted.
1645 class PrefetchAllocationNode : public Node {
1646 public:
1647 PrefetchAllocationNode(Node *mem, Node *adr) : Node(0,mem,adr) {}
1648 virtual int Opcode() const;
1649 virtual uint ideal_reg() const { return NotAMachineReg; }
1650 virtual uint match_edge(uint idx) const { return idx==2; }
1651 virtual const Type *bottom_type() const { return ( AllocatePrefetchStyle == 3 ) ? Type::MEMORY : Type::ABIO; }
1652 };
1653
1654 #endif // SHARE_OPTO_MEMNODE_HPP