1 /*
2 * Copyright (c) 1997, 2018, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
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7 * published by the Free Software Foundation.
8 *
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 // Store bit to memory
626 class StoreZ0Node : public StoreBNode {
627 public:
628 StoreZ0Node(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
629 : StoreBNode(c, mem, adr, at, val, mo) {}
630 virtual int Opcode() const;
631 };
632
633 class StoreZ1Node : public StoreBNode {
634 public:
635 StoreZ1Node(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
636 : StoreBNode(c, mem, adr, at, val, mo) {}
637 virtual int Opcode() const;
638 };
639
640 //------------------------------StoreCNode-------------------------------------
641 // Store char/short to memory
642 class StoreCNode : public StoreNode {
643 public:
644 StoreCNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
645 : StoreNode(c, mem, adr, at, val, mo) {}
646 virtual int Opcode() const;
647 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
648 virtual BasicType memory_type() const { return T_CHAR; }
649 };
650
651 //------------------------------StoreINode-------------------------------------
652 // Store int to memory
653 class StoreINode : public StoreNode {
654 public:
655 StoreINode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
656 : StoreNode(c, mem, adr, at, val, mo) {}
657 virtual int Opcode() const;
658 virtual BasicType memory_type() const { return T_INT; }
659 };
660
661 //------------------------------StoreLNode-------------------------------------
662 // Store long to memory
663 class StoreLNode : public StoreNode {
664 virtual uint hash() const { return StoreNode::hash() + _require_atomic_access; }
665 virtual uint cmp( const Node &n ) const {
666 return _require_atomic_access == ((StoreLNode&)n)._require_atomic_access
667 && StoreNode::cmp(n);
668 }
669 virtual uint size_of() const { return sizeof(*this); }
670 const bool _require_atomic_access; // is piecewise store forbidden?
671
672 public:
673 StoreLNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo, bool require_atomic_access = false)
674 : StoreNode(c, mem, adr, at, val, mo), _require_atomic_access(require_atomic_access) {}
675 virtual int Opcode() const;
676 virtual BasicType memory_type() const { return T_LONG; }
677 bool require_atomic_access() const { return _require_atomic_access; }
678 static StoreLNode* make_atomic(Node* ctl, Node* mem, Node* adr, const TypePtr* adr_type, Node* val, MemOrd mo);
679 #ifndef PRODUCT
680 virtual void dump_spec(outputStream *st) const {
681 StoreNode::dump_spec(st);
682 if (_require_atomic_access) st->print(" Atomic!");
683 }
684 #endif
685 };
686
687 //------------------------------StoreFNode-------------------------------------
688 // Store float to memory
689 class StoreFNode : public StoreNode {
690 public:
691 StoreFNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
692 : StoreNode(c, mem, adr, at, val, mo) {}
693 virtual int Opcode() const;
694 virtual BasicType memory_type() const { return T_FLOAT; }
695 };
696
697 //------------------------------StoreDNode-------------------------------------
698 // Store double to memory
699 class StoreDNode : public StoreNode {
700 virtual uint hash() const { return StoreNode::hash() + _require_atomic_access; }
701 virtual uint cmp( const Node &n ) const {
702 return _require_atomic_access == ((StoreDNode&)n)._require_atomic_access
703 && StoreNode::cmp(n);
704 }
705 virtual uint size_of() const { return sizeof(*this); }
706 const bool _require_atomic_access; // is piecewise store forbidden?
707 public:
708 StoreDNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val,
709 MemOrd mo, bool require_atomic_access = false)
710 : StoreNode(c, mem, adr, at, val, mo), _require_atomic_access(require_atomic_access) {}
711 virtual int Opcode() const;
712 virtual BasicType memory_type() const { return T_DOUBLE; }
713 bool require_atomic_access() const { return _require_atomic_access; }
714 static StoreDNode* make_atomic(Node* ctl, Node* mem, Node* adr, const TypePtr* adr_type, Node* val, MemOrd mo);
715 #ifndef PRODUCT
716 virtual void dump_spec(outputStream *st) const {
717 StoreNode::dump_spec(st);
718 if (_require_atomic_access) st->print(" Atomic!");
719 }
720 #endif
721
722 };
723
724 //------------------------------StorePNode-------------------------------------
725 // Store pointer to memory
726 class StorePNode : public StoreNode {
727 public:
728 StorePNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
729 : StoreNode(c, mem, adr, at, val, mo) {}
730 virtual int Opcode() const;
731 virtual BasicType memory_type() const { return T_ADDRESS; }
732 };
733
734 //------------------------------StoreNNode-------------------------------------
735 // Store narrow oop to memory
736 class StoreNNode : public StoreNode {
737 public:
738 StoreNNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
739 : StoreNode(c, mem, adr, at, val, mo) {}
740 virtual int Opcode() const;
741 virtual BasicType memory_type() const { return T_NARROWOOP; }
742 };
743
744 //------------------------------StoreNKlassNode--------------------------------------
745 // Store narrow klass to memory
746 class StoreNKlassNode : public StoreNNode {
747 public:
748 StoreNKlassNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
749 : StoreNNode(c, mem, adr, at, val, mo) {}
750 virtual int Opcode() const;
751 virtual BasicType memory_type() const { return T_NARROWKLASS; }
752 };
753
754 //------------------------------StoreCMNode-----------------------------------
755 // Store card-mark byte to memory for CM
756 // The last StoreCM before a SafePoint must be preserved and occur after its "oop" store
757 // Preceeding equivalent StoreCMs may be eliminated.
758 class StoreCMNode : public StoreNode {
759 private:
760 virtual uint hash() const { return StoreNode::hash() + _oop_alias_idx; }
761 virtual uint cmp( const Node &n ) const {
762 return _oop_alias_idx == ((StoreCMNode&)n)._oop_alias_idx
763 && StoreNode::cmp(n);
764 }
765 virtual uint size_of() const { return sizeof(*this); }
766 int _oop_alias_idx; // The alias_idx of OopStore
767
768 public:
769 StoreCMNode( Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, Node *oop_store, int oop_alias_idx ) :
770 StoreNode(c, mem, adr, at, val, oop_store, MemNode::release),
771 _oop_alias_idx(oop_alias_idx) {
772 assert(_oop_alias_idx >= Compile::AliasIdxRaw ||
773 _oop_alias_idx == Compile::AliasIdxBot && Compile::current()->AliasLevel() == 0,
774 "bad oop alias idx");
775 }
776 virtual int Opcode() const;
777 virtual Node* Identity(PhaseGVN* phase);
778 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
779 virtual const Type* Value(PhaseGVN* phase) const;
780 virtual BasicType memory_type() const { return T_VOID; } // unspecific
781 int oop_alias_idx() const { return _oop_alias_idx; }
782 };
783
784 //------------------------------LoadPLockedNode---------------------------------
785 // Load-locked a pointer from memory (either object or array).
786 // On Sparc & Intel this is implemented as a normal pointer load.
787 // On PowerPC and friends it's a real load-locked.
788 class LoadPLockedNode : public LoadPNode {
789 public:
790 LoadPLockedNode(Node *c, Node *mem, Node *adr, MemOrd mo)
791 : LoadPNode(c, mem, adr, TypeRawPtr::BOTTOM, TypeRawPtr::BOTTOM, mo) {}
792 virtual int Opcode() const;
793 virtual int store_Opcode() const { return Op_StorePConditional; }
794 virtual bool depends_only_on_test() const { return true; }
795 };
796
797 //------------------------------SCMemProjNode---------------------------------------
798 // This class defines a projection of the memory state of a store conditional node.
799 // These nodes return a value, but also update memory.
800 class SCMemProjNode : public ProjNode {
801 public:
802 enum {SCMEMPROJCON = (uint)-2};
803 SCMemProjNode( Node *src) : ProjNode( src, SCMEMPROJCON) { }
804 virtual int Opcode() const;
805 virtual bool is_CFG() const { return false; }
806 virtual const Type *bottom_type() const {return Type::MEMORY;}
807 virtual const TypePtr *adr_type() const {
808 Node* ctrl = in(0);
809 if (ctrl == NULL) return NULL; // node is dead
810 return ctrl->in(MemNode::Memory)->adr_type();
811 }
812 virtual uint ideal_reg() const { return 0;} // memory projections don't have a register
813 virtual const Type* Value(PhaseGVN* phase) const;
814 #ifndef PRODUCT
815 virtual void dump_spec(outputStream *st) const {};
816 #endif
817 };
818
819 //------------------------------LoadStoreNode---------------------------
820 // Note: is_Mem() method returns 'true' for this class.
821 class LoadStoreNode : public Node {
822 private:
823 const Type* const _type; // What kind of value is loaded?
824 const TypePtr* _adr_type; // What kind of memory is being addressed?
825 virtual uint size_of() const; // Size is bigger
826 public:
827 LoadStoreNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at, const Type* rt, uint required );
828 virtual bool depends_only_on_test() const { return false; }
829 virtual uint match_edge(uint idx) const { return idx == MemNode::Address || idx == MemNode::ValueIn; }
830
831 virtual const Type *bottom_type() const { return _type; }
832 virtual uint ideal_reg() const;
833 virtual const class TypePtr *adr_type() const { return _adr_type; } // returns bottom_type of address
834
835 bool result_not_used() const;
836 MemBarNode* trailing_membar() const;
837 };
838
839 class LoadStoreConditionalNode : public LoadStoreNode {
840 public:
841 enum {
842 ExpectedIn = MemNode::ValueIn+1 // One more input than MemNode
843 };
844 LoadStoreConditionalNode(Node *c, Node *mem, Node *adr, Node *val, Node *ex);
845 };
846
847 //------------------------------StorePConditionalNode---------------------------
848 // Conditionally store pointer to memory, if no change since prior
849 // load-locked. Sets flags for success or failure of the store.
850 class StorePConditionalNode : public LoadStoreConditionalNode {
851 public:
852 StorePConditionalNode( Node *c, Node *mem, Node *adr, Node *val, Node *ll ) : LoadStoreConditionalNode(c, mem, adr, val, ll) { }
853 virtual int Opcode() const;
854 // Produces flags
855 virtual uint ideal_reg() const { return Op_RegFlags; }
856 };
857
858 //------------------------------StoreIConditionalNode---------------------------
859 // Conditionally store int to memory, if no change since prior
860 // load-locked. Sets flags for success or failure of the store.
861 class StoreIConditionalNode : public LoadStoreConditionalNode {
862 public:
863 StoreIConditionalNode( Node *c, Node *mem, Node *adr, Node *val, Node *ii ) : LoadStoreConditionalNode(c, mem, adr, val, ii) { }
864 virtual int Opcode() const;
865 // Produces flags
866 virtual uint ideal_reg() const { return Op_RegFlags; }
867 };
868
869 //------------------------------StoreLConditionalNode---------------------------
870 // Conditionally store long to memory, if no change since prior
871 // load-locked. Sets flags for success or failure of the store.
872 class StoreLConditionalNode : public LoadStoreConditionalNode {
873 public:
874 StoreLConditionalNode( Node *c, Node *mem, Node *adr, Node *val, Node *ll ) : LoadStoreConditionalNode(c, mem, adr, val, ll) { }
875 virtual int Opcode() const;
876 // Produces flags
877 virtual uint ideal_reg() const { return Op_RegFlags; }
878 };
879
880 class CompareAndSwapNode : public LoadStoreConditionalNode {
881 private:
882 const MemNode::MemOrd _mem_ord;
883 public:
884 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) {}
885 MemNode::MemOrd order() const {
886 return _mem_ord;
887 }
888 };
889
890 class CompareAndExchangeNode : public LoadStoreNode {
891 private:
892 const MemNode::MemOrd _mem_ord;
893 public:
894 enum {
895 ExpectedIn = MemNode::ValueIn+1 // One more input than MemNode
896 };
897 CompareAndExchangeNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord, const TypePtr* at, const Type* t) :
898 LoadStoreNode(c, mem, adr, val, at, t, 5), _mem_ord(mem_ord) {
899 init_req(ExpectedIn, ex );
900 }
901
902 MemNode::MemOrd order() const {
903 return _mem_ord;
904 }
905 };
906
907 //------------------------------CompareAndSwapBNode---------------------------
908 class CompareAndSwapBNode : public CompareAndSwapNode {
909 public:
910 CompareAndSwapBNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
911 virtual int Opcode() const;
912 };
913
914 //------------------------------CompareAndSwapSNode---------------------------
915 class CompareAndSwapSNode : public CompareAndSwapNode {
916 public:
917 CompareAndSwapSNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
918 virtual int Opcode() const;
919 };
920
921 //------------------------------CompareAndSwapINode---------------------------
922 class CompareAndSwapINode : public CompareAndSwapNode {
923 public:
924 CompareAndSwapINode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
925 virtual int Opcode() const;
926 };
927
928 //------------------------------CompareAndSwapLNode---------------------------
929 class CompareAndSwapLNode : public CompareAndSwapNode {
930 public:
931 CompareAndSwapLNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
932 virtual int Opcode() const;
933 };
934
935 //------------------------------CompareAndSwapPNode---------------------------
936 class CompareAndSwapPNode : public CompareAndSwapNode {
937 public:
938 CompareAndSwapPNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
939 virtual int Opcode() const;
940 };
941
942 //------------------------------CompareAndSwapNNode---------------------------
943 class CompareAndSwapNNode : public CompareAndSwapNode {
944 public:
945 CompareAndSwapNNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
946 virtual int Opcode() const;
947 };
948
949 //------------------------------WeakCompareAndSwapBNode---------------------------
950 class WeakCompareAndSwapBNode : public CompareAndSwapNode {
951 public:
952 WeakCompareAndSwapBNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
953 virtual int Opcode() const;
954 };
955
956 //------------------------------WeakCompareAndSwapSNode---------------------------
957 class WeakCompareAndSwapSNode : public CompareAndSwapNode {
958 public:
959 WeakCompareAndSwapSNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
960 virtual int Opcode() const;
961 };
962
963 //------------------------------WeakCompareAndSwapINode---------------------------
964 class WeakCompareAndSwapINode : public CompareAndSwapNode {
965 public:
966 WeakCompareAndSwapINode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
967 virtual int Opcode() const;
968 };
969
970 //------------------------------WeakCompareAndSwapLNode---------------------------
971 class WeakCompareAndSwapLNode : public CompareAndSwapNode {
972 public:
973 WeakCompareAndSwapLNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
974 virtual int Opcode() const;
975 };
976
977 //------------------------------WeakCompareAndSwapPNode---------------------------
978 class WeakCompareAndSwapPNode : public CompareAndSwapNode {
979 public:
980 WeakCompareAndSwapPNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
981 virtual int Opcode() const;
982 };
983
984 //------------------------------WeakCompareAndSwapNNode---------------------------
985 class WeakCompareAndSwapNNode : public CompareAndSwapNode {
986 public:
987 WeakCompareAndSwapNNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapNode(c, mem, adr, val, ex, mem_ord) { }
988 virtual int Opcode() const;
989 };
990
991 //------------------------------CompareAndExchangeBNode---------------------------
992 class CompareAndExchangeBNode : public CompareAndExchangeNode {
993 public:
994 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) { }
995 virtual int Opcode() const;
996 };
997
998
999 //------------------------------CompareAndExchangeSNode---------------------------
1000 class CompareAndExchangeSNode : public CompareAndExchangeNode {
1001 public:
1002 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) { }
1003 virtual int Opcode() const;
1004 };
1005
1006 //------------------------------CompareAndExchangeLNode---------------------------
1007 class CompareAndExchangeLNode : public CompareAndExchangeNode {
1008 public:
1009 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) { }
1010 virtual int Opcode() const;
1011 };
1012
1013
1014 //------------------------------CompareAndExchangeINode---------------------------
1015 class CompareAndExchangeINode : public CompareAndExchangeNode {
1016 public:
1017 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) { }
1018 virtual int Opcode() const;
1019 };
1020
1021
1022 //------------------------------CompareAndExchangePNode---------------------------
1023 class CompareAndExchangePNode : public CompareAndExchangeNode {
1024 public:
1025 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) { }
1026 virtual int Opcode() const;
1027 };
1028
1029 //------------------------------CompareAndExchangeNNode---------------------------
1030 class CompareAndExchangeNNode : public CompareAndExchangeNode {
1031 public:
1032 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) { }
1033 virtual int Opcode() const;
1034 };
1035
1036 //------------------------------GetAndAddBNode---------------------------
1037 class GetAndAddBNode : public LoadStoreNode {
1038 public:
1039 GetAndAddBNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeInt::BYTE, 4) { }
1040 virtual int Opcode() const;
1041 };
1042
1043 //------------------------------GetAndAddSNode---------------------------
1044 class GetAndAddSNode : public LoadStoreNode {
1045 public:
1046 GetAndAddSNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeInt::SHORT, 4) { }
1047 virtual int Opcode() const;
1048 };
1049
1050 //------------------------------GetAndAddINode---------------------------
1051 class GetAndAddINode : public LoadStoreNode {
1052 public:
1053 GetAndAddINode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeInt::INT, 4) { }
1054 virtual int Opcode() const;
1055 };
1056
1057 //------------------------------GetAndAddLNode---------------------------
1058 class GetAndAddLNode : public LoadStoreNode {
1059 public:
1060 GetAndAddLNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeLong::LONG, 4) { }
1061 virtual int Opcode() const;
1062 };
1063
1064 //------------------------------GetAndSetBNode---------------------------
1065 class GetAndSetBNode : public LoadStoreNode {
1066 public:
1067 GetAndSetBNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeInt::BYTE, 4) { }
1068 virtual int Opcode() const;
1069 };
1070
1071 //------------------------------GetAndSetSNode---------------------------
1072 class GetAndSetSNode : public LoadStoreNode {
1073 public:
1074 GetAndSetSNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeInt::SHORT, 4) { }
1075 virtual int Opcode() const;
1076 };
1077
1078 //------------------------------GetAndSetINode---------------------------
1079 class GetAndSetINode : public LoadStoreNode {
1080 public:
1081 GetAndSetINode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeInt::INT, 4) { }
1082 virtual int Opcode() const;
1083 };
1084
1085 //------------------------------GetAndSetLNode---------------------------
1086 class GetAndSetLNode : public LoadStoreNode {
1087 public:
1088 GetAndSetLNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeLong::LONG, 4) { }
1089 virtual int Opcode() const;
1090 };
1091
1092 //------------------------------GetAndSetPNode---------------------------
1093 class GetAndSetPNode : public LoadStoreNode {
1094 public:
1095 GetAndSetPNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at, const Type* t ) : LoadStoreNode(c, mem, adr, val, at, t, 4) { }
1096 virtual int Opcode() const;
1097 };
1098
1099 //------------------------------GetAndSetNNode---------------------------
1100 class GetAndSetNNode : public LoadStoreNode {
1101 public:
1102 GetAndSetNNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at, const Type* t ) : LoadStoreNode(c, mem, adr, val, at, t, 4) { }
1103 virtual int Opcode() const;
1104 };
1105
1106 //------------------------------ClearArray-------------------------------------
1107 class ClearArrayNode: public Node {
1108 private:
1109 bool _is_large;
1110 public:
1111 ClearArrayNode( Node *ctrl, Node *arymem, Node *word_cnt, Node *base, bool is_large)
1112 : Node(ctrl,arymem,word_cnt,base), _is_large(is_large) {
1113 init_class_id(Class_ClearArray);
1114 }
1115 virtual int Opcode() const;
1116 virtual const Type *bottom_type() const { return Type::MEMORY; }
1117 // ClearArray modifies array elements, and so affects only the
1118 // array memory addressed by the bottom_type of its base address.
1119 virtual const class TypePtr *adr_type() const;
1120 virtual Node* Identity(PhaseGVN* phase);
1121 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
1122 virtual uint match_edge(uint idx) const;
1123 bool is_large() const { return _is_large; }
1124
1125 // Clear the given area of an object or array.
1126 // The start offset must always be aligned mod BytesPerInt.
1127 // The end offset must always be aligned mod BytesPerLong.
1128 // Return the new memory.
1129 static Node* clear_memory(Node* control, Node* mem, Node* dest,
1130 intptr_t start_offset,
1131 intptr_t end_offset,
1132 PhaseGVN* phase);
1133 static Node* clear_memory(Node* control, Node* mem, Node* dest,
1134 intptr_t start_offset,
1135 Node* end_offset,
1136 PhaseGVN* phase);
1137 static Node* clear_memory(Node* control, Node* mem, Node* dest,
1138 Node* start_offset,
1139 Node* end_offset,
1140 PhaseGVN* phase);
1141 // Return allocation input memory edge if it is different instance
1142 // or itself if it is the one we are looking for.
1143 static bool step_through(Node** np, uint instance_id, PhaseTransform* phase);
1144 };
1145
1146 //------------------------------MemBar-----------------------------------------
1147 // There are different flavors of Memory Barriers to match the Java Memory
1148 // Model. Monitor-enter and volatile-load act as Aquires: no following ref
1149 // can be moved to before them. We insert a MemBar-Acquire after a FastLock or
1150 // volatile-load. Monitor-exit and volatile-store act as Release: no
1151 // preceding ref can be moved to after them. We insert a MemBar-Release
1152 // before a FastUnlock or volatile-store. All volatiles need to be
1153 // serialized, so we follow all volatile-stores with a MemBar-Volatile to
1154 // separate it from any following volatile-load.
1155 class MemBarNode: public MultiNode {
1156 virtual uint hash() const ; // { return NO_HASH; }
1157 virtual uint cmp( const Node &n ) const ; // Always fail, except on self
1158
1159 virtual uint size_of() const { return sizeof(*this); }
1160 // Memory type this node is serializing. Usually either rawptr or bottom.
1161 const TypePtr* _adr_type;
1162
1163 // How is this membar related to a nearby memory access?
1164 enum {
1165 Standalone,
1166 TrailingLoad,
1167 TrailingStore,
1168 LeadingStore,
1169 TrailingLoadStore,
1170 LeadingLoadStore
1171 } _kind;
1172
1173 #ifdef ASSERT
1174 uint _pair_idx;
1175 #endif
1176
1177 public:
1178 enum {
1179 Precedent = TypeFunc::Parms // optional edge to force precedence
1180 };
1181 MemBarNode(Compile* C, int alias_idx, Node* precedent);
1182 virtual int Opcode() const = 0;
1183 virtual const class TypePtr *adr_type() const { return _adr_type; }
1184 virtual const Type* Value(PhaseGVN* phase) const;
1185 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
1186 virtual uint match_edge(uint idx) const { return 0; }
1187 virtual const Type *bottom_type() const { return TypeTuple::MEMBAR; }
1188 virtual Node *match( const ProjNode *proj, const Matcher *m );
1189 // Factory method. Builds a wide or narrow membar.
1190 // Optional 'precedent' becomes an extra edge if not null.
1191 static MemBarNode* make(Compile* C, int opcode,
1192 int alias_idx = Compile::AliasIdxBot,
1193 Node* precedent = NULL);
1194
1195 MemBarNode* trailing_membar() const;
1196 MemBarNode* leading_membar() const;
1197
1198 void set_trailing_load() { _kind = TrailingLoad; }
1199 bool trailing_load() const { return _kind == TrailingLoad; }
1200 bool trailing_store() const { return _kind == TrailingStore; }
1201 bool leading_store() const { return _kind == LeadingStore; }
1202 bool trailing_load_store() const { return _kind == TrailingLoadStore; }
1203 bool leading_load_store() const { return _kind == LeadingLoadStore; }
1204 bool trailing() const { return _kind == TrailingLoad || _kind == TrailingStore || _kind == TrailingLoadStore; }
1205 bool leading() const { return _kind == LeadingStore || _kind == LeadingLoadStore; }
1206 bool standalone() const { return _kind == Standalone; }
1207
1208 static void set_store_pair(MemBarNode* leading, MemBarNode* trailing);
1209 static void set_load_store_pair(MemBarNode* leading, MemBarNode* trailing);
1210
1211 void remove(PhaseIterGVN *igvn);
1212 };
1213
1214 // "Acquire" - no following ref can move before (but earlier refs can
1215 // follow, like an early Load stalled in cache). Requires multi-cpu
1216 // visibility. Inserted after a volatile load.
1217 class MemBarAcquireNode: public MemBarNode {
1218 public:
1219 MemBarAcquireNode(Compile* C, int alias_idx, Node* precedent)
1220 : MemBarNode(C, alias_idx, precedent) {}
1221 virtual int Opcode() const;
1222 };
1223
1224 // "Acquire" - no following ref can move before (but earlier refs can
1225 // follow, like an early Load stalled in cache). Requires multi-cpu
1226 // visibility. Inserted independ of any load, as required
1227 // for intrinsic Unsafe.loadFence().
1228 class LoadFenceNode: public MemBarNode {
1229 public:
1230 LoadFenceNode(Compile* C, int alias_idx, Node* precedent)
1231 : MemBarNode(C, alias_idx, precedent) {}
1232 virtual int Opcode() const;
1233 };
1234
1235 // "Release" - no earlier ref can move after (but later refs can move
1236 // up, like a speculative pipelined cache-hitting Load). Requires
1237 // multi-cpu visibility. Inserted before a volatile store.
1238 class MemBarReleaseNode: public MemBarNode {
1239 public:
1240 MemBarReleaseNode(Compile* C, int alias_idx, Node* precedent)
1241 : MemBarNode(C, alias_idx, precedent) {}
1242 virtual int Opcode() const;
1243 };
1244
1245 // "Release" - no earlier ref can move after (but later refs can move
1246 // up, like a speculative pipelined cache-hitting Load). Requires
1247 // multi-cpu visibility. Inserted independent of any store, as required
1248 // for intrinsic Unsafe.storeFence().
1249 class StoreFenceNode: public MemBarNode {
1250 public:
1251 StoreFenceNode(Compile* C, int alias_idx, Node* precedent)
1252 : MemBarNode(C, alias_idx, precedent) {}
1253 virtual int Opcode() const;
1254 };
1255
1256 // "Acquire" - no following ref can move before (but earlier refs can
1257 // follow, like an early Load stalled in cache). Requires multi-cpu
1258 // visibility. Inserted after a FastLock.
1259 class MemBarAcquireLockNode: public MemBarNode {
1260 public:
1261 MemBarAcquireLockNode(Compile* C, int alias_idx, Node* precedent)
1262 : MemBarNode(C, alias_idx, precedent) {}
1263 virtual int Opcode() const;
1264 };
1265
1266 // "Release" - no earlier ref can move after (but later refs can move
1267 // up, like a speculative pipelined cache-hitting Load). Requires
1268 // multi-cpu visibility. Inserted before a FastUnLock.
1269 class MemBarReleaseLockNode: public MemBarNode {
1270 public:
1271 MemBarReleaseLockNode(Compile* C, int alias_idx, Node* precedent)
1272 : MemBarNode(C, alias_idx, precedent) {}
1273 virtual int Opcode() const;
1274 };
1275
1276 class MemBarStoreStoreNode: public MemBarNode {
1277 public:
1278 MemBarStoreStoreNode(Compile* C, int alias_idx, Node* precedent)
1279 : MemBarNode(C, alias_idx, precedent) {
1280 init_class_id(Class_MemBarStoreStore);
1281 }
1282 virtual int Opcode() const;
1283 };
1284
1285 // Ordering between a volatile store and a following volatile load.
1286 // Requires multi-CPU visibility?
1287 class MemBarVolatileNode: public MemBarNode {
1288 public:
1289 MemBarVolatileNode(Compile* C, int alias_idx, Node* precedent)
1290 : MemBarNode(C, alias_idx, precedent) {}
1291 virtual int Opcode() const;
1292 };
1293
1294 // Ordering within the same CPU. Used to order unsafe memory references
1295 // inside the compiler when we lack alias info. Not needed "outside" the
1296 // compiler because the CPU does all the ordering for us.
1297 class MemBarCPUOrderNode: public MemBarNode {
1298 public:
1299 MemBarCPUOrderNode(Compile* C, int alias_idx, Node* precedent)
1300 : MemBarNode(C, alias_idx, precedent) {}
1301 virtual int Opcode() const;
1302 virtual uint ideal_reg() const { return 0; } // not matched in the AD file
1303 };
1304
1305 class OnSpinWaitNode: public MemBarNode {
1306 public:
1307 OnSpinWaitNode(Compile* C, int alias_idx, Node* precedent)
1308 : MemBarNode(C, alias_idx, precedent) {}
1309 virtual int Opcode() const;
1310 };
1311
1312 // Isolation of object setup after an AllocateNode and before next safepoint.
1313 // (See comment in memnode.cpp near InitializeNode::InitializeNode for semantics.)
1314 class InitializeNode: public MemBarNode {
1315 friend class AllocateNode;
1316
1317 enum {
1318 Incomplete = 0,
1319 Complete = 1,
1320 WithArraycopy = 2
1321 };
1322 int _is_complete;
1323
1324 bool _does_not_escape;
1325
1326 public:
1327 enum {
1328 Control = TypeFunc::Control,
1329 Memory = TypeFunc::Memory, // MergeMem for states affected by this op
1330 RawAddress = TypeFunc::Parms+0, // the newly-allocated raw address
1331 RawStores = TypeFunc::Parms+1 // zero or more stores (or TOP)
1332 };
1333
1334 InitializeNode(Compile* C, int adr_type, Node* rawoop);
1335 virtual int Opcode() const;
1336 virtual uint size_of() const { return sizeof(*this); }
1337 virtual uint ideal_reg() const { return 0; } // not matched in the AD file
1338 virtual const RegMask &in_RegMask(uint) const; // mask for RawAddress
1339
1340 // Manage incoming memory edges via a MergeMem on in(Memory):
1341 Node* memory(uint alias_idx);
1342
1343 // The raw memory edge coming directly from the Allocation.
1344 // The contents of this memory are *always* all-zero-bits.
1345 Node* zero_memory() { return memory(Compile::AliasIdxRaw); }
1346
1347 // Return the corresponding allocation for this initialization (or null if none).
1348 // (Note: Both InitializeNode::allocation and AllocateNode::initialization
1349 // are defined in graphKit.cpp, which sets up the bidirectional relation.)
1350 AllocateNode* allocation();
1351
1352 // Anything other than zeroing in this init?
1353 bool is_non_zero();
1354
1355 // An InitializeNode must completed before macro expansion is done.
1356 // Completion requires that the AllocateNode must be followed by
1357 // initialization of the new memory to zero, then to any initializers.
1358 bool is_complete() { return _is_complete != Incomplete; }
1359 bool is_complete_with_arraycopy() { return (_is_complete & WithArraycopy) != 0; }
1360
1361 // Mark complete. (Must not yet be complete.)
1362 void set_complete(PhaseGVN* phase);
1363 void set_complete_with_arraycopy() { _is_complete = Complete | WithArraycopy; }
1364
1365 bool does_not_escape() { return _does_not_escape; }
1366 void set_does_not_escape() { _does_not_escape = true; }
1367
1368 #ifdef ASSERT
1369 // ensure all non-degenerate stores are ordered and non-overlapping
1370 bool stores_are_sane(PhaseTransform* phase);
1371 #endif //ASSERT
1372
1373 // See if this store can be captured; return offset where it initializes.
1374 // Return 0 if the store cannot be moved (any sort of problem).
1375 intptr_t can_capture_store(StoreNode* st, PhaseTransform* phase, bool can_reshape);
1376
1377 // Capture another store; reformat it to write my internal raw memory.
1378 // Return the captured copy, else NULL if there is some sort of problem.
1379 Node* capture_store(StoreNode* st, intptr_t start, PhaseTransform* phase, bool can_reshape);
1380
1381 // Find captured store which corresponds to the range [start..start+size).
1382 // Return my own memory projection (meaning the initial zero bits)
1383 // if there is no such store. Return NULL if there is a problem.
1384 Node* find_captured_store(intptr_t start, int size_in_bytes, PhaseTransform* phase);
1385
1386 // Called when the associated AllocateNode is expanded into CFG.
1387 Node* complete_stores(Node* rawctl, Node* rawmem, Node* rawptr,
1388 intptr_t header_size, Node* size_in_bytes,
1389 PhaseGVN* phase);
1390
1391 private:
1392 void remove_extra_zeroes();
1393
1394 // Find out where a captured store should be placed (or already is placed).
1395 int captured_store_insertion_point(intptr_t start, int size_in_bytes,
1396 PhaseTransform* phase);
1397
1398 static intptr_t get_store_offset(Node* st, PhaseTransform* phase);
1399
1400 Node* make_raw_address(intptr_t offset, PhaseTransform* phase);
1401
1402 bool detect_init_independence(Node* n, int& count);
1403
1404 void coalesce_subword_stores(intptr_t header_size, Node* size_in_bytes,
1405 PhaseGVN* phase);
1406
1407 intptr_t find_next_fullword_store(uint i, PhaseGVN* phase);
1408 };
1409
1410 //------------------------------MergeMem---------------------------------------
1411 // (See comment in memnode.cpp near MergeMemNode::MergeMemNode for semantics.)
1412 class MergeMemNode: public Node {
1413 virtual uint hash() const ; // { return NO_HASH; }
1414 virtual uint cmp( const Node &n ) const ; // Always fail, except on self
1415 friend class MergeMemStream;
1416 MergeMemNode(Node* def); // clients use MergeMemNode::make
1417
1418 public:
1419 // If the input is a whole memory state, clone it with all its slices intact.
1420 // Otherwise, make a new memory state with just that base memory input.
1421 // In either case, the result is a newly created MergeMem.
1422 static MergeMemNode* make(Node* base_memory);
1423
1424 virtual int Opcode() const;
1425 virtual Node* Identity(PhaseGVN* phase);
1426 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
1427 virtual uint ideal_reg() const { return NotAMachineReg; }
1428 virtual uint match_edge(uint idx) const { return 0; }
1429 virtual const RegMask &out_RegMask() const;
1430 virtual const Type *bottom_type() const { return Type::MEMORY; }
1431 virtual const TypePtr *adr_type() const { return TypePtr::BOTTOM; }
1432 // sparse accessors
1433 // Fetch the previously stored "set_memory_at", or else the base memory.
1434 // (Caller should clone it if it is a phi-nest.)
1435 Node* memory_at(uint alias_idx) const;
1436 // set the memory, regardless of its previous value
1437 void set_memory_at(uint alias_idx, Node* n);
1438 // the "base" is the memory that provides the non-finite support
1439 Node* base_memory() const { return in(Compile::AliasIdxBot); }
1440 // warning: setting the base can implicitly set any of the other slices too
1441 void set_base_memory(Node* def);
1442 // sentinel value which denotes a copy of the base memory:
1443 Node* empty_memory() const { return in(Compile::AliasIdxTop); }
1444 static Node* make_empty_memory(); // where the sentinel comes from
1445 bool is_empty_memory(Node* n) const { assert((n == empty_memory()) == n->is_top(), "sanity"); return n->is_top(); }
1446 // hook for the iterator, to perform any necessary setup
1447 void iteration_setup(const MergeMemNode* other = NULL);
1448 // push sentinels until I am at least as long as the other (semantic no-op)
1449 void grow_to_match(const MergeMemNode* other);
1450 bool verify_sparse() const PRODUCT_RETURN0;
1451 #ifndef PRODUCT
1452 virtual void dump_spec(outputStream *st) const;
1453 #endif
1454 };
1455
1456 class MergeMemStream : public StackObj {
1457 private:
1458 MergeMemNode* _mm;
1459 const MergeMemNode* _mm2; // optional second guy, contributes non-empty iterations
1460 Node* _mm_base; // loop-invariant base memory of _mm
1461 int _idx;
1462 int _cnt;
1463 Node* _mem;
1464 Node* _mem2;
1465 int _cnt2;
1466
1467 void init(MergeMemNode* mm, const MergeMemNode* mm2 = NULL) {
1468 // subsume_node will break sparseness at times, whenever a memory slice
1469 // folds down to a copy of the base ("fat") memory. In such a case,
1470 // the raw edge will update to base, although it should be top.
1471 // This iterator will recognize either top or base_memory as an
1472 // "empty" slice. See is_empty, is_empty2, and next below.
1473 //
1474 // The sparseness property is repaired in MergeMemNode::Ideal.
1475 // As long as access to a MergeMem goes through this iterator
1476 // or the memory_at accessor, flaws in the sparseness will
1477 // never be observed.
1478 //
1479 // Also, iteration_setup repairs sparseness.
1480 assert(mm->verify_sparse(), "please, no dups of base");
1481 assert(mm2==NULL || mm2->verify_sparse(), "please, no dups of base");
1482
1483 _mm = mm;
1484 _mm_base = mm->base_memory();
1485 _mm2 = mm2;
1486 _cnt = mm->req();
1487 _idx = Compile::AliasIdxBot-1; // start at the base memory
1488 _mem = NULL;
1489 _mem2 = NULL;
1490 }
1491
1492 #ifdef ASSERT
1493 Node* check_memory() const {
1494 if (at_base_memory())
1495 return _mm->base_memory();
1496 else if ((uint)_idx < _mm->req() && !_mm->in(_idx)->is_top())
1497 return _mm->memory_at(_idx);
1498 else
1499 return _mm_base;
1500 }
1501 Node* check_memory2() const {
1502 return at_base_memory()? _mm2->base_memory(): _mm2->memory_at(_idx);
1503 }
1504 #endif
1505
1506 static bool match_memory(Node* mem, const MergeMemNode* mm, int idx) PRODUCT_RETURN0;
1507 void assert_synch() const {
1508 assert(!_mem || _idx >= _cnt || match_memory(_mem, _mm, _idx),
1509 "no side-effects except through the stream");
1510 }
1511
1512 public:
1513
1514 // expected usages:
1515 // for (MergeMemStream mms(mem->is_MergeMem()); next_non_empty(); ) { ... }
1516 // for (MergeMemStream mms(mem1, mem2); next_non_empty2(); ) { ... }
1517
1518 // iterate over one merge
1519 MergeMemStream(MergeMemNode* mm) {
1520 mm->iteration_setup();
1521 init(mm);
1522 debug_only(_cnt2 = 999);
1523 }
1524 // iterate in parallel over two merges
1525 // only iterates through non-empty elements of mm2
1526 MergeMemStream(MergeMemNode* mm, const MergeMemNode* mm2) {
1527 assert(mm2, "second argument must be a MergeMem also");
1528 ((MergeMemNode*)mm2)->iteration_setup(); // update hidden state
1529 mm->iteration_setup(mm2);
1530 init(mm, mm2);
1531 _cnt2 = mm2->req();
1532 }
1533 #ifdef ASSERT
1534 ~MergeMemStream() {
1535 assert_synch();
1536 }
1537 #endif
1538
1539 MergeMemNode* all_memory() const {
1540 return _mm;
1541 }
1542 Node* base_memory() const {
1543 assert(_mm_base == _mm->base_memory(), "no update to base memory, please");
1544 return _mm_base;
1545 }
1546 const MergeMemNode* all_memory2() const {
1547 assert(_mm2 != NULL, "");
1548 return _mm2;
1549 }
1550 bool at_base_memory() const {
1551 return _idx == Compile::AliasIdxBot;
1552 }
1553 int alias_idx() const {
1554 assert(_mem, "must call next 1st");
1555 return _idx;
1556 }
1557
1558 const TypePtr* adr_type() const {
1559 return Compile::current()->get_adr_type(alias_idx());
1560 }
1561
1562 const TypePtr* adr_type(Compile* C) const {
1563 return C->get_adr_type(alias_idx());
1564 }
1565 bool is_empty() const {
1566 assert(_mem, "must call next 1st");
1567 assert(_mem->is_top() == (_mem==_mm->empty_memory()), "correct sentinel");
1568 return _mem->is_top();
1569 }
1570 bool is_empty2() const {
1571 assert(_mem2, "must call next 1st");
1572 assert(_mem2->is_top() == (_mem2==_mm2->empty_memory()), "correct sentinel");
1573 return _mem2->is_top();
1574 }
1575 Node* memory() const {
1576 assert(!is_empty(), "must not be empty");
1577 assert_synch();
1578 return _mem;
1579 }
1580 // get the current memory, regardless of empty or non-empty status
1581 Node* force_memory() const {
1582 assert(!is_empty() || !at_base_memory(), "");
1583 // Use _mm_base to defend against updates to _mem->base_memory().
1584 Node *mem = _mem->is_top() ? _mm_base : _mem;
1585 assert(mem == check_memory(), "");
1586 return mem;
1587 }
1588 Node* memory2() const {
1589 assert(_mem2 == check_memory2(), "");
1590 return _mem2;
1591 }
1592 void set_memory(Node* mem) {
1593 if (at_base_memory()) {
1594 // Note that this does not change the invariant _mm_base.
1595 _mm->set_base_memory(mem);
1596 } else {
1597 _mm->set_memory_at(_idx, mem);
1598 }
1599 _mem = mem;
1600 assert_synch();
1601 }
1602
1603 // Recover from a side effect to the MergeMemNode.
1604 void set_memory() {
1605 _mem = _mm->in(_idx);
1606 }
1607
1608 bool next() { return next(false); }
1609 bool next2() { return next(true); }
1610
1611 bool next_non_empty() { return next_non_empty(false); }
1612 bool next_non_empty2() { return next_non_empty(true); }
1613 // next_non_empty2 can yield states where is_empty() is true
1614
1615 private:
1616 // find the next item, which might be empty
1617 bool next(bool have_mm2) {
1618 assert((_mm2 != NULL) == have_mm2, "use other next");
1619 assert_synch();
1620 if (++_idx < _cnt) {
1621 // Note: This iterator allows _mm to be non-sparse.
1622 // It behaves the same whether _mem is top or base_memory.
1623 _mem = _mm->in(_idx);
1624 if (have_mm2)
1625 _mem2 = _mm2->in((_idx < _cnt2) ? _idx : Compile::AliasIdxTop);
1626 return true;
1627 }
1628 return false;
1629 }
1630
1631 // find the next non-empty item
1632 bool next_non_empty(bool have_mm2) {
1633 while (next(have_mm2)) {
1634 if (!is_empty()) {
1635 // make sure _mem2 is filled in sensibly
1636 if (have_mm2 && _mem2->is_top()) _mem2 = _mm2->base_memory();
1637 return true;
1638 } else if (have_mm2 && !is_empty2()) {
1639 return true; // is_empty() == true
1640 }
1641 }
1642 return false;
1643 }
1644 };
1645
1646 //------------------------------Prefetch---------------------------------------
1647
1648 // Allocation prefetch which may fault, TLAB size have to be adjusted.
1649 class PrefetchAllocationNode : public Node {
1650 public:
1651 PrefetchAllocationNode(Node *mem, Node *adr) : Node(0,mem,adr) {}
1652 virtual int Opcode() const;
1653 virtual uint ideal_reg() const { return NotAMachineReg; }
1654 virtual uint match_edge(uint idx) const { return idx==2; }
1655 virtual const Type *bottom_type() const { return ( AllocatePrefetchStyle == 3 ) ? Type::MEMORY : Type::ABIO; }
1656 };
1657
1658 #endif // SHARE_VM_OPTO_MEMNODE_HPP