1 /*
2 * Copyright (c) 1997, 2017, 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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8 *
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11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
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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 } MemOrd;
61 protected:
62 MemNode( Node *c0, Node *c1, Node *c2, const TypePtr* at )
63 : Node(c0,c1,c2 ), _unaligned_access(false), _mismatched_access(false) {
64 init_class_id(Class_Mem);
65 debug_only(_adr_type=at; adr_type();)
66 }
67 MemNode( Node *c0, Node *c1, Node *c2, const TypePtr* at, Node *c3 )
68 : Node(c0,c1,c2,c3), _unaligned_access(false), _mismatched_access(false) {
69 init_class_id(Class_Mem);
70 debug_only(_adr_type=at; adr_type();)
71 }
72 MemNode( Node *c0, Node *c1, Node *c2, const TypePtr* at, Node *c3, Node *c4)
73 : Node(c0,c1,c2,c3,c4), _unaligned_access(false), _mismatched_access(false) {
74 init_class_id(Class_Mem);
75 debug_only(_adr_type=at; adr_type();)
76 }
77
78 static bool check_if_adr_maybe_raw(Node* adr);
79
80 public:
81 // Helpers for the optimizer. Documented in memnode.cpp.
82 static bool detect_ptr_independence(Node* p1, AllocateNode* a1,
83 Node* p2, AllocateNode* a2,
84 PhaseTransform* phase);
85 static bool adr_phi_is_loop_invariant(Node* adr_phi, Node* cast);
86
87 static Node *optimize_simple_memory_chain(Node *mchain, const TypeOopPtr *t_oop, Node *load, PhaseGVN *phase);
88 static Node *optimize_memory_chain(Node *mchain, const TypePtr *t_adr, Node *load, PhaseGVN *phase);
89 // This one should probably be a phase-specific function:
90 static bool all_controls_dominate(Node* dom, Node* sub);
91
92 // Find any cast-away of null-ness and keep its control.
93 static Node *Ideal_common_DU_postCCP( PhaseCCP *ccp, Node* n, Node* adr );
94 virtual Node *Ideal_DU_postCCP( PhaseCCP *ccp );
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
142 #ifndef PRODUCT
143 static void dump_adr_type(const Node* mem, const TypePtr* adr_type, outputStream *st);
144 virtual void dump_spec(outputStream *st) const;
145 #endif
146 };
147
148 //------------------------------LoadNode---------------------------------------
149 // Load value; requires Memory and Address
150 class LoadNode : public MemNode {
151 public:
152 // Some loads (from unsafe) should be pinned: they don't depend only
153 // on the dominating test. The boolean field _depends_only_on_test
154 // below records whether that node depends only on the dominating
155 // test.
156 // Methods used to build LoadNodes pass an argument of type enum
157 // ControlDependency instead of a boolean because those methods
158 // typically have multiple boolean parameters with default values:
159 // passing the wrong boolean to one of these parameters by mistake
160 // goes easily unnoticed. Using an enum, the compiler can check that
161 // the type of a value and the type of the parameter match.
162 enum ControlDependency {
163 Pinned,
164 DependsOnlyOnTest
165 };
166 private:
167 // LoadNode::hash() doesn't take the _depends_only_on_test field
168 // into account: If the graph already has a non-pinned LoadNode and
169 // we add a pinned LoadNode with the same inputs, it's safe for GVN
170 // to replace the pinned LoadNode with the non-pinned LoadNode,
171 // otherwise it wouldn't be safe to have a non pinned LoadNode with
172 // those inputs in the first place. If the graph already has a
173 // pinned LoadNode and we add a non pinned LoadNode with the same
174 // inputs, it's safe (but suboptimal) for GVN to replace the
175 // non-pinned LoadNode by the pinned LoadNode.
176 bool _depends_only_on_test;
177
178 // On platforms with weak memory ordering (e.g., PPC, Ia64) we distinguish
179 // loads that can be reordered, and such requiring acquire semantics to
180 // adhere to the Java specification. The required behaviour is stored in
181 // this field.
182 const MemOrd _mo;
183
184 protected:
185 virtual uint cmp(const Node &n) const;
186 virtual uint size_of() const; // Size is bigger
187 // Should LoadNode::Ideal() attempt to remove control edges?
188 virtual bool can_remove_control() const;
189 const Type* const _type; // What kind of value is loaded?
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), _type(rt), _mo(mo), _depends_only_on_test(control_dependency == DependsOnlyOnTest) {
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
202 // Polymorphic factory method:
203 static Node* make(PhaseGVN& gvn, Node *c, Node *mem, Node *adr,
204 const TypePtr* at, const Type *rt, BasicType bt,
205 MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest);
206
207 virtual uint hash() const; // Check the type
208
209 // Handle algebraic identities here. If we have an identity, return the Node
210 // we are equivalent to. We look for Load of a Store.
211 virtual Node *Identity( PhaseTransform *phase );
212
213 // If the load is from Field memory and the pointer is non-null, it might be possible to
214 // zero out the control input.
215 // If the offset is constant and the base is an object allocation,
216 // try to hook me up to the exact initializing store.
217 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
218
219 // Split instance field load through Phi.
220 Node* split_through_phi(PhaseGVN *phase);
221
222 // Recover original value from boxed values
223 Node *eliminate_autobox(PhaseGVN *phase);
224
225 // Compute a new Type for this node. Basically we just do the pre-check,
226 // then call the virtual add() to set the type.
227 virtual const Type *Value( PhaseTransform *phase ) const;
228
229 // Common methods for LoadKlass and LoadNKlass nodes.
230 const Type *klass_value_common( PhaseTransform *phase ) const;
231 Node *klass_identity_common( PhaseTransform *phase );
232
233 virtual uint ideal_reg() const;
234 virtual const Type *bottom_type() const;
235 // Following method is copied from TypeNode:
236 void set_type(const Type* t) {
237 assert(t != NULL, "sanity");
238 debug_only(uint check_hash = (VerifyHashTableKeys && _hash_lock) ? hash() : NO_HASH);
239 *(const Type**)&_type = t; // cast away const-ness
240 // If this node is in the hash table, make sure it doesn't need a rehash.
241 assert(check_hash == NO_HASH || check_hash == hash(), "type change must preserve hash code");
242 }
243 const Type* type() const { assert(_type != NULL, "sanity"); return _type; };
244
245 // Do not match memory edge
246 virtual uint match_edge(uint idx) const;
247
248 // Map a load opcode to its corresponding store opcode.
249 virtual int store_Opcode() const = 0;
250
251 // Check if the load's memory input is a Phi node with the same control.
252 bool is_instance_field_load_with_local_phi(Node* ctrl);
253
254 #ifndef PRODUCT
255 virtual void dump_spec(outputStream *st) const;
256 #endif
257 #ifdef ASSERT
258 // Helper function to allow a raw load without control edge for some cases
259 static bool is_immutable_value(Node* adr);
260 #endif
261 protected:
262 const Type* load_array_final_field(const TypeKlassPtr *tkls,
263 ciKlass* klass) const;
264 // depends_only_on_test is almost always true, and needs to be almost always
265 // true to enable key hoisting & commoning optimizations. However, for the
266 // special case of RawPtr loads from TLS top & end, and other loads performed by
267 // GC barriers, the control edge carries the dependence preventing hoisting past
268 // a Safepoint instead of the memory edge. (An unfortunate consequence of having
269 // Safepoints not set Raw Memory; itself an unfortunate consequence of having Nodes
270 // which produce results (new raw memory state) inside of loops preventing all
271 // manner of other optimizations). Basically, it's ugly but so is the alternative.
272 // See comment in macro.cpp, around line 125 expand_allocate_common().
273 virtual bool depends_only_on_test() const { return adr_type() != TypeRawPtr::BOTTOM && _depends_only_on_test; }
274 };
275
276 //------------------------------LoadBNode--------------------------------------
277 // Load a byte (8bits signed) from memory
278 class LoadBNode : public LoadNode {
279 public:
280 LoadBNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeInt *ti, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
281 : LoadNode(c, mem, adr, at, ti, mo, control_dependency) {}
282 virtual int Opcode() const;
283 virtual uint ideal_reg() const { return Op_RegI; }
284 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
285 virtual const Type *Value(PhaseTransform *phase) const;
286 virtual int store_Opcode() const { return Op_StoreB; }
287 virtual BasicType memory_type() const { return T_BYTE; }
288 };
289
290 //------------------------------LoadUBNode-------------------------------------
291 // Load a unsigned byte (8bits unsigned) from memory
292 class LoadUBNode : public LoadNode {
293 public:
294 LoadUBNode(Node* c, Node* mem, Node* adr, const TypePtr* at, const TypeInt* ti, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
295 : LoadNode(c, mem, adr, at, ti, mo, control_dependency) {}
296 virtual int Opcode() const;
297 virtual uint ideal_reg() const { return Op_RegI; }
298 virtual Node* Ideal(PhaseGVN *phase, bool can_reshape);
299 virtual const Type *Value(PhaseTransform *phase) const;
300 virtual int store_Opcode() const { return Op_StoreB; }
301 virtual BasicType memory_type() const { return T_BYTE; }
302 };
303
304 //------------------------------LoadUSNode-------------------------------------
305 // Load an unsigned short/char (16bits unsigned) from memory
306 class LoadUSNode : public LoadNode {
307 public:
308 LoadUSNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeInt *ti, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
309 : LoadNode(c, mem, adr, at, ti, mo, control_dependency) {}
310 virtual int Opcode() const;
311 virtual uint ideal_reg() const { return Op_RegI; }
312 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
313 virtual const Type *Value(PhaseTransform *phase) const;
314 virtual int store_Opcode() const { return Op_StoreC; }
315 virtual BasicType memory_type() const { return T_CHAR; }
316 };
317
318 //------------------------------LoadSNode--------------------------------------
319 // Load a short (16bits signed) from memory
320 class LoadSNode : public LoadNode {
321 public:
322 LoadSNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeInt *ti, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
323 : LoadNode(c, mem, adr, at, ti, mo, control_dependency) {}
324 virtual int Opcode() const;
325 virtual uint ideal_reg() const { return Op_RegI; }
326 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
327 virtual const Type *Value(PhaseTransform *phase) const;
328 virtual int store_Opcode() const { return Op_StoreC; }
329 virtual BasicType memory_type() const { return T_SHORT; }
330 };
331
332 //------------------------------LoadINode--------------------------------------
333 // Load an integer from memory
334 class LoadINode : public LoadNode {
335 public:
336 LoadINode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeInt *ti, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
337 : LoadNode(c, mem, adr, at, ti, mo, control_dependency) {}
338 virtual int Opcode() const;
339 virtual uint ideal_reg() const { return Op_RegI; }
340 virtual int store_Opcode() const { return Op_StoreI; }
341 virtual BasicType memory_type() const { return T_INT; }
342 };
343
344 //------------------------------LoadRangeNode----------------------------------
345 // Load an array length from the array
346 class LoadRangeNode : public LoadINode {
347 public:
348 LoadRangeNode(Node *c, Node *mem, Node *adr, const TypeInt *ti = TypeInt::POS)
349 : LoadINode(c, mem, adr, TypeAryPtr::RANGE, ti, MemNode::unordered) {}
350 virtual int Opcode() const;
351 virtual const Type *Value( PhaseTransform *phase ) const;
352 virtual Node *Identity( PhaseTransform *phase );
353 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
354 };
355
356 //------------------------------LoadLNode--------------------------------------
357 // Load a long from memory
358 class LoadLNode : public LoadNode {
359 virtual uint hash() const { return LoadNode::hash() + _require_atomic_access; }
360 virtual uint cmp( const Node &n ) const {
361 return _require_atomic_access == ((LoadLNode&)n)._require_atomic_access
362 && LoadNode::cmp(n);
363 }
364 virtual uint size_of() const { return sizeof(*this); }
365 const bool _require_atomic_access; // is piecewise load forbidden?
366
367 public:
368 LoadLNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeLong *tl,
369 MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest, bool require_atomic_access = false)
370 : LoadNode(c, mem, adr, at, tl, mo, control_dependency), _require_atomic_access(require_atomic_access) {}
371 virtual int Opcode() const;
372 virtual uint ideal_reg() const { return Op_RegL; }
373 virtual int store_Opcode() const { return Op_StoreL; }
374 virtual BasicType memory_type() const { return T_LONG; }
375 bool require_atomic_access() const { return _require_atomic_access; }
376 static LoadLNode* make_atomic(Compile *C, Node* ctl, Node* mem, Node* adr, const TypePtr* adr_type,
377 const Type* rt, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest);
378 #ifndef PRODUCT
379 virtual void dump_spec(outputStream *st) const {
380 LoadNode::dump_spec(st);
381 if (_require_atomic_access) st->print(" Atomic!");
382 }
383 #endif
384 };
385
386 //------------------------------LoadL_unalignedNode----------------------------
387 // Load a long from unaligned memory
388 class LoadL_unalignedNode : public LoadLNode {
389 public:
390 LoadL_unalignedNode(Node *c, Node *mem, Node *adr, const TypePtr* at, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
391 : LoadLNode(c, mem, adr, at, TypeLong::LONG, mo, control_dependency) {}
392 virtual int Opcode() const;
393 };
394
395 //------------------------------LoadFNode--------------------------------------
396 // Load a float (64 bits) from memory
397 class LoadFNode : public LoadNode {
398 public:
399 LoadFNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const Type *t, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
400 : LoadNode(c, mem, adr, at, t, mo, control_dependency) {}
401 virtual int Opcode() const;
402 virtual uint ideal_reg() const { return Op_RegF; }
403 virtual int store_Opcode() const { return Op_StoreF; }
404 virtual BasicType memory_type() const { return T_FLOAT; }
405 };
406
407 //------------------------------LoadDNode--------------------------------------
408 // Load a double (64 bits) from memory
409 class LoadDNode : public LoadNode {
410 virtual uint hash() const { return LoadNode::hash() + _require_atomic_access; }
411 virtual uint cmp( const Node &n ) const {
412 return _require_atomic_access == ((LoadDNode&)n)._require_atomic_access
413 && LoadNode::cmp(n);
414 }
415 virtual uint size_of() const { return sizeof(*this); }
416 const bool _require_atomic_access; // is piecewise load forbidden?
417
418 public:
419 LoadDNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const Type *t,
420 MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest, bool require_atomic_access = false)
421 : LoadNode(c, mem, adr, at, t, mo, control_dependency), _require_atomic_access(require_atomic_access) {}
422 virtual int Opcode() const;
423 virtual uint ideal_reg() const { return Op_RegD; }
424 virtual int store_Opcode() const { return Op_StoreD; }
425 virtual BasicType memory_type() const { return T_DOUBLE; }
426 bool require_atomic_access() const { return _require_atomic_access; }
427 static LoadDNode* make_atomic(Compile *C, Node* ctl, Node* mem, Node* adr, const TypePtr* adr_type,
428 const Type* rt, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest);
429 #ifndef PRODUCT
430 virtual void dump_spec(outputStream *st) const {
431 LoadNode::dump_spec(st);
432 if (_require_atomic_access) st->print(" Atomic!");
433 }
434 #endif
435 };
436
437 //------------------------------LoadD_unalignedNode----------------------------
438 // Load a double from unaligned memory
439 class LoadD_unalignedNode : public LoadDNode {
440 public:
441 LoadD_unalignedNode(Node *c, Node *mem, Node *adr, const TypePtr* at, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
442 : LoadDNode(c, mem, adr, at, Type::DOUBLE, mo, control_dependency) {}
443 virtual int Opcode() const;
444 };
445
446 //------------------------------LoadPNode--------------------------------------
447 // Load a pointer from memory (either object or array)
448 class LoadPNode : public LoadNode {
449 public:
450 LoadPNode(Node *c, Node *mem, Node *adr, const TypePtr *at, const TypePtr* t, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
451 : LoadNode(c, mem, adr, at, t, mo, control_dependency) {}
452 virtual int Opcode() const;
453 virtual uint ideal_reg() const { return Op_RegP; }
454 virtual int store_Opcode() const { return Op_StoreP; }
455 virtual BasicType memory_type() const { return T_ADDRESS; }
456 };
457
458
459 //------------------------------LoadNNode--------------------------------------
460 // Load a narrow oop from memory (either object or array)
461 class LoadNNode : public LoadNode {
462 public:
463 LoadNNode(Node *c, Node *mem, Node *adr, const TypePtr *at, const Type* t, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
464 : LoadNode(c, mem, adr, at, t, mo, control_dependency) {}
465 virtual int Opcode() const;
466 virtual uint ideal_reg() const { return Op_RegN; }
467 virtual int store_Opcode() const { return Op_StoreN; }
468 virtual BasicType memory_type() const { return T_NARROWOOP; }
469 };
470
471 //------------------------------LoadKlassNode----------------------------------
472 // Load a Klass from an object
473 class LoadKlassNode : public LoadPNode {
474 protected:
475 // In most cases, LoadKlassNode does not have the control input set. If the control
476 // input is set, it must not be removed (by LoadNode::Ideal()).
477 virtual bool can_remove_control() const;
478 public:
479 LoadKlassNode(Node *c, Node *mem, Node *adr, const TypePtr *at, const TypeKlassPtr *tk, MemOrd mo)
480 : LoadPNode(c, mem, adr, at, tk, mo) {}
481 virtual int Opcode() const;
482 virtual const Type *Value( PhaseTransform *phase ) const;
483 virtual Node *Identity( PhaseTransform *phase );
484 virtual bool depends_only_on_test() const { return true; }
485
486 // Polymorphic factory method:
487 static Node* make(PhaseGVN& gvn, Node* ctl, Node* mem, Node* adr, const TypePtr* at,
488 const TypeKlassPtr* tk = TypeKlassPtr::OBJECT);
489 };
490
491 //------------------------------LoadNKlassNode---------------------------------
492 // Load a narrow Klass from an object.
493 class LoadNKlassNode : public LoadNNode {
494 public:
495 LoadNKlassNode(Node *c, Node *mem, Node *adr, const TypePtr *at, const TypeNarrowKlass *tk, MemOrd mo)
496 : LoadNNode(c, mem, adr, at, tk, mo) {}
497 virtual int Opcode() const;
498 virtual uint ideal_reg() const { return Op_RegN; }
499 virtual int store_Opcode() const { return Op_StoreNKlass; }
500 virtual BasicType memory_type() const { return T_NARROWKLASS; }
501
502 virtual const Type *Value( PhaseTransform *phase ) const;
503 virtual Node *Identity( PhaseTransform *phase );
504 virtual bool depends_only_on_test() const { return true; }
505 };
506
507
508 //------------------------------StoreNode--------------------------------------
509 // Store value; requires Store, Address and Value
510 class StoreNode : public MemNode {
511 private:
512 // On platforms with weak memory ordering (e.g., PPC, Ia64) we distinguish
513 // stores that can be reordered, and such requiring release semantics to
514 // adhere to the Java specification. The required behaviour is stored in
515 // this field.
516 const MemOrd _mo;
517 // Needed for proper cloning.
518 virtual uint size_of() const { return sizeof(*this); }
519 protected:
520 virtual uint cmp( const Node &n ) const;
521 virtual bool depends_only_on_test() const { return false; }
522
523 Node *Ideal_masked_input (PhaseGVN *phase, uint mask);
524 Node *Ideal_sign_extended_input(PhaseGVN *phase, int num_bits);
525
526 public:
527 // We must ensure that stores of object references will be visible
528 // only after the object's initialization. So the callers of this
529 // procedure must indicate that the store requires `release'
530 // semantics, if the stored value is an object reference that might
531 // point to a new object and may become externally visible.
532 StoreNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
533 : MemNode(c, mem, adr, at, val), _mo(mo) {
534 init_class_id(Class_Store);
535 }
536 StoreNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, Node *oop_store, MemOrd mo)
537 : MemNode(c, mem, adr, at, val, oop_store), _mo(mo) {
538 init_class_id(Class_Store);
539 }
540
541 inline bool is_unordered() const { return !is_release(); }
542 inline bool is_release() const {
543 assert((_mo == unordered || _mo == release), "unexpected");
544 return _mo == release;
545 }
546
547 // Conservatively release stores of object references in order to
548 // ensure visibility of object initialization.
549 static inline MemOrd release_if_reference(const BasicType t) {
550 const MemOrd mo = (t == T_ARRAY ||
551 t == T_ADDRESS || // Might be the address of an object reference (`boxing').
552 t == T_OBJECT) ? release : unordered;
553 return mo;
554 }
555
556 // Polymorphic factory method
557 //
558 // We must ensure that stores of object references will be visible
559 // only after the object's initialization. So the callers of this
560 // procedure must indicate that the store requires `release'
561 // semantics, if the stored value is an object reference that might
562 // point to a new object and may become externally visible.
563 static StoreNode* make(PhaseGVN& gvn, Node *c, Node *mem, Node *adr,
564 const TypePtr* at, Node *val, BasicType bt, MemOrd mo);
565
566 virtual uint hash() const; // Check the type
567
568 // If the store is to Field memory and the pointer is non-null, we can
569 // zero out the control input.
570 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
571
572 // Compute a new Type for this node. Basically we just do the pre-check,
573 // then call the virtual add() to set the type.
574 virtual const Type *Value( PhaseTransform *phase ) const;
575
576 // Check for identity function on memory (Load then Store at same address)
577 virtual Node *Identity( PhaseTransform *phase );
578
579 // Do not match memory edge
580 virtual uint match_edge(uint idx) const;
581
582 virtual const Type *bottom_type() const; // returns Type::MEMORY
583
584 // Map a store opcode to its corresponding own opcode, trivially.
585 virtual int store_Opcode() const { return Opcode(); }
586
587 // have all possible loads of the value stored been optimized away?
588 bool value_never_loaded(PhaseTransform *phase) const;
589
590 MemBarNode* trailing_membar() const;
591 };
592
593 //------------------------------StoreBNode-------------------------------------
594 // Store byte to memory
595 class StoreBNode : public StoreNode {
596 public:
597 StoreBNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
598 : StoreNode(c, mem, adr, at, val, mo) {}
599 virtual int Opcode() const;
600 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
601 virtual BasicType memory_type() const { return T_BYTE; }
602 };
603
604 //------------------------------StoreCNode-------------------------------------
605 // Store char/short to memory
606 class StoreCNode : public StoreNode {
607 public:
608 StoreCNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
609 : StoreNode(c, mem, adr, at, val, mo) {}
610 virtual int Opcode() const;
611 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
612 virtual BasicType memory_type() const { return T_CHAR; }
613 };
614
615 //------------------------------StoreINode-------------------------------------
616 // Store int to memory
617 class StoreINode : public StoreNode {
618 public:
619 StoreINode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
620 : StoreNode(c, mem, adr, at, val, mo) {}
621 virtual int Opcode() const;
622 virtual BasicType memory_type() const { return T_INT; }
623 };
624
625 //------------------------------StoreLNode-------------------------------------
626 // Store long to memory
627 class StoreLNode : public StoreNode {
628 virtual uint hash() const { return StoreNode::hash() + _require_atomic_access; }
629 virtual uint cmp( const Node &n ) const {
630 return _require_atomic_access == ((StoreLNode&)n)._require_atomic_access
631 && StoreNode::cmp(n);
632 }
633 virtual uint size_of() const { return sizeof(*this); }
634 const bool _require_atomic_access; // is piecewise store forbidden?
635
636 public:
637 StoreLNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo, bool require_atomic_access = false)
638 : StoreNode(c, mem, adr, at, val, mo), _require_atomic_access(require_atomic_access) {}
639 virtual int Opcode() const;
640 virtual BasicType memory_type() const { return T_LONG; }
641 bool require_atomic_access() const { return _require_atomic_access; }
642 static StoreLNode* make_atomic(Compile *C, Node* ctl, Node* mem, Node* adr, const TypePtr* adr_type, Node* val, MemOrd mo);
643 #ifndef PRODUCT
644 virtual void dump_spec(outputStream *st) const {
645 StoreNode::dump_spec(st);
646 if (_require_atomic_access) st->print(" Atomic!");
647 }
648 #endif
649 };
650
651 //------------------------------StoreFNode-------------------------------------
652 // Store float to memory
653 class StoreFNode : public StoreNode {
654 public:
655 StoreFNode(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_FLOAT; }
659 };
660
661 //------------------------------StoreDNode-------------------------------------
662 // Store double to memory
663 class StoreDNode : 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 == ((StoreDNode&)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 public:
672 StoreDNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val,
673 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_DOUBLE; }
677 bool require_atomic_access() const { return _require_atomic_access; }
678 static StoreDNode* make_atomic(Compile *C, 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
688 //------------------------------StorePNode-------------------------------------
689 // Store pointer to memory
690 class StorePNode : public StoreNode {
691 public:
692 StorePNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
693 : StoreNode(c, mem, adr, at, val, mo) {}
694 virtual int Opcode() const;
695 virtual BasicType memory_type() const { return T_ADDRESS; }
696 };
697
698 //------------------------------StoreNNode-------------------------------------
699 // Store narrow oop to memory
700 class StoreNNode : public StoreNode {
701 public:
702 StoreNNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
703 : StoreNode(c, mem, adr, at, val, mo) {}
704 virtual int Opcode() const;
705 virtual BasicType memory_type() const { return T_NARROWOOP; }
706 };
707
708 //------------------------------StoreNKlassNode--------------------------------------
709 // Store narrow klass to memory
710 class StoreNKlassNode : public StoreNNode {
711 public:
712 StoreNKlassNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
713 : StoreNNode(c, mem, adr, at, val, mo) {}
714 virtual int Opcode() const;
715 virtual BasicType memory_type() const { return T_NARROWKLASS; }
716 };
717
718 //------------------------------StoreCMNode-----------------------------------
719 // Store card-mark byte to memory for CM
720 // The last StoreCM before a SafePoint must be preserved and occur after its "oop" store
721 // Preceeding equivalent StoreCMs may be eliminated.
722 class StoreCMNode : public StoreNode {
723 private:
724 virtual uint hash() const { return StoreNode::hash() + _oop_alias_idx; }
725 virtual uint cmp( const Node &n ) const {
726 return _oop_alias_idx == ((StoreCMNode&)n)._oop_alias_idx
727 && StoreNode::cmp(n);
728 }
729 virtual uint size_of() const { return sizeof(*this); }
730 int _oop_alias_idx; // The alias_idx of OopStore
731
732 public:
733 StoreCMNode( Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, Node *oop_store, int oop_alias_idx ) :
734 StoreNode(c, mem, adr, at, val, oop_store, MemNode::release),
735 _oop_alias_idx(oop_alias_idx) {
736 assert(_oop_alias_idx >= Compile::AliasIdxRaw ||
737 _oop_alias_idx == Compile::AliasIdxBot && Compile::current()->AliasLevel() == 0,
738 "bad oop alias idx");
739 }
740 virtual int Opcode() const;
741 virtual Node *Identity( PhaseTransform *phase );
742 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
743 virtual const Type *Value( PhaseTransform *phase ) const;
744 virtual BasicType memory_type() const { return T_VOID; } // unspecific
745 int oop_alias_idx() const { return _oop_alias_idx; }
746 };
747
748 //------------------------------LoadPLockedNode---------------------------------
749 // Load-locked a pointer from memory (either object or array).
750 // On Sparc & Intel this is implemented as a normal pointer load.
751 // On PowerPC and friends it's a real load-locked.
752 class LoadPLockedNode : public LoadPNode {
753 public:
754 LoadPLockedNode(Node *c, Node *mem, Node *adr, MemOrd mo)
755 : LoadPNode(c, mem, adr, TypeRawPtr::BOTTOM, TypeRawPtr::BOTTOM, mo) {}
756 virtual int Opcode() const;
757 virtual int store_Opcode() const { return Op_StorePConditional; }
758 virtual bool depends_only_on_test() const { return true; }
759 };
760
761 //------------------------------SCMemProjNode---------------------------------------
762 // This class defines a projection of the memory state of a store conditional node.
763 // These nodes return a value, but also update memory.
764 class SCMemProjNode : public ProjNode {
765 public:
766 enum {SCMEMPROJCON = (uint)-2};
767 SCMemProjNode( Node *src) : ProjNode( src, SCMEMPROJCON) { }
768 virtual int Opcode() const;
769 virtual bool is_CFG() const { return false; }
770 virtual const Type *bottom_type() const {return Type::MEMORY;}
771 virtual const TypePtr *adr_type() const { return in(0)->in(MemNode::Memory)->adr_type();}
772 virtual uint ideal_reg() const { return 0;} // memory projections don't have a register
773 virtual const Type *Value( PhaseTransform *phase ) const;
774 #ifndef PRODUCT
775 virtual void dump_spec(outputStream *st) const {};
776 #endif
777 };
778
779 //------------------------------LoadStoreNode---------------------------
780 // Note: is_Mem() method returns 'true' for this class.
781 class LoadStoreNode : public Node {
782 private:
783 const Type* const _type; // What kind of value is loaded?
784 const TypePtr* _adr_type; // What kind of memory is being addressed?
785 virtual uint size_of() const; // Size is bigger
786 public:
787 LoadStoreNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at, const Type* rt, uint required );
788 virtual bool depends_only_on_test() const { return false; }
789 virtual uint match_edge(uint idx) const { return idx == MemNode::Address || idx == MemNode::ValueIn; }
790
791 virtual const Type *bottom_type() const { return _type; }
792 virtual uint ideal_reg() const;
793 virtual const class TypePtr *adr_type() const { return _adr_type; } // returns bottom_type of address
794
795 bool result_not_used() const;
796 MemBarNode* trailing_membar() const;
797 };
798
799 class LoadStoreConditionalNode : public LoadStoreNode {
800 public:
801 enum {
802 ExpectedIn = MemNode::ValueIn+1 // One more input than MemNode
803 };
804 LoadStoreConditionalNode(Node *c, Node *mem, Node *adr, Node *val, Node *ex);
805 };
806
807 //------------------------------StorePConditionalNode---------------------------
808 // Conditionally store pointer to memory, if no change since prior
809 // load-locked. Sets flags for success or failure of the store.
810 class StorePConditionalNode : public LoadStoreConditionalNode {
811 public:
812 StorePConditionalNode( Node *c, Node *mem, Node *adr, Node *val, Node *ll ) : LoadStoreConditionalNode(c, mem, adr, val, ll) { }
813 virtual int Opcode() const;
814 // Produces flags
815 virtual uint ideal_reg() const { return Op_RegFlags; }
816 };
817
818 //------------------------------StoreIConditionalNode---------------------------
819 // Conditionally store int to memory, if no change since prior
820 // load-locked. Sets flags for success or failure of the store.
821 class StoreIConditionalNode : public LoadStoreConditionalNode {
822 public:
823 StoreIConditionalNode( Node *c, Node *mem, Node *adr, Node *val, Node *ii ) : LoadStoreConditionalNode(c, mem, adr, val, ii) { }
824 virtual int Opcode() const;
825 // Produces flags
826 virtual uint ideal_reg() const { return Op_RegFlags; }
827 };
828
829 //------------------------------StoreLConditionalNode---------------------------
830 // Conditionally store long to memory, if no change since prior
831 // load-locked. Sets flags for success or failure of the store.
832 class StoreLConditionalNode : public LoadStoreConditionalNode {
833 public:
834 StoreLConditionalNode( Node *c, Node *mem, Node *adr, Node *val, Node *ll ) : LoadStoreConditionalNode(c, mem, adr, val, ll) { }
835 virtual int Opcode() const;
836 // Produces flags
837 virtual uint ideal_reg() const { return Op_RegFlags; }
838 };
839
840
841 //------------------------------CompareAndSwapLNode---------------------------
842 class CompareAndSwapLNode : public LoadStoreConditionalNode {
843 public:
844 CompareAndSwapLNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex) : LoadStoreConditionalNode(c, mem, adr, val, ex) { }
845 virtual int Opcode() const;
846 };
847
848
849 //------------------------------CompareAndSwapINode---------------------------
850 class CompareAndSwapINode : public LoadStoreConditionalNode {
851 public:
852 CompareAndSwapINode( Node *c, Node *mem, Node *adr, Node *val, Node *ex) : LoadStoreConditionalNode(c, mem, adr, val, ex) { }
853 virtual int Opcode() const;
854 };
855
856
857 //------------------------------CompareAndSwapPNode---------------------------
858 class CompareAndSwapPNode : public LoadStoreConditionalNode {
859 public:
860 CompareAndSwapPNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex) : LoadStoreConditionalNode(c, mem, adr, val, ex) { }
861 virtual int Opcode() const;
862 };
863
864 //------------------------------CompareAndSwapNNode---------------------------
865 class CompareAndSwapNNode : public LoadStoreConditionalNode {
866 public:
867 CompareAndSwapNNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex) : LoadStoreConditionalNode(c, mem, adr, val, ex) { }
868 virtual int Opcode() const;
869 };
870
871 //------------------------------GetAndAddINode---------------------------
872 class GetAndAddINode : public LoadStoreNode {
873 public:
874 GetAndAddINode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeInt::INT, 4) { }
875 virtual int Opcode() const;
876 };
877
878 //------------------------------GetAndAddLNode---------------------------
879 class GetAndAddLNode : public LoadStoreNode {
880 public:
881 GetAndAddLNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeLong::LONG, 4) { }
882 virtual int Opcode() const;
883 };
884
885
886 //------------------------------GetAndSetINode---------------------------
887 class GetAndSetINode : public LoadStoreNode {
888 public:
889 GetAndSetINode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeInt::INT, 4) { }
890 virtual int Opcode() const;
891 };
892
893 //------------------------------GetAndSetINode---------------------------
894 class GetAndSetLNode : public LoadStoreNode {
895 public:
896 GetAndSetLNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeLong::LONG, 4) { }
897 virtual int Opcode() const;
898 };
899
900 //------------------------------GetAndSetPNode---------------------------
901 class GetAndSetPNode : public LoadStoreNode {
902 public:
903 GetAndSetPNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at, const Type* t ) : LoadStoreNode(c, mem, adr, val, at, t, 4) { }
904 virtual int Opcode() const;
905 };
906
907 //------------------------------GetAndSetNNode---------------------------
908 class GetAndSetNNode : public LoadStoreNode {
909 public:
910 GetAndSetNNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at, const Type* t ) : LoadStoreNode(c, mem, adr, val, at, t, 4) { }
911 virtual int Opcode() const;
912 };
913
914 //------------------------------ClearArray-------------------------------------
915 class ClearArrayNode: public Node {
916 public:
917 ClearArrayNode( Node *ctrl, Node *arymem, Node *word_cnt, Node *base )
918 : Node(ctrl,arymem,word_cnt,base) {
919 init_class_id(Class_ClearArray);
920 }
921 virtual int Opcode() const;
922 virtual const Type *bottom_type() const { return Type::MEMORY; }
923 // ClearArray modifies array elements, and so affects only the
924 // array memory addressed by the bottom_type of its base address.
925 virtual const class TypePtr *adr_type() const;
926 virtual Node *Identity( PhaseTransform *phase );
927 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
928 virtual uint match_edge(uint idx) const;
929
930 // Clear the given area of an object or array.
931 // The start offset must always be aligned mod BytesPerInt.
932 // The end offset must always be aligned mod BytesPerLong.
933 // Return the new memory.
934 static Node* clear_memory(Node* control, Node* mem, Node* dest,
935 intptr_t start_offset,
936 intptr_t end_offset,
937 PhaseGVN* phase);
938 static Node* clear_memory(Node* control, Node* mem, Node* dest,
939 intptr_t start_offset,
940 Node* end_offset,
941 PhaseGVN* phase);
942 static Node* clear_memory(Node* control, Node* mem, Node* dest,
943 Node* start_offset,
944 Node* end_offset,
945 PhaseGVN* phase);
946 // Return allocation input memory edge if it is different instance
947 // or itself if it is the one we are looking for.
948 static bool step_through(Node** np, uint instance_id, PhaseTransform* phase);
949 };
950
951 //------------------------------StrIntrinsic-------------------------------
952 // Base class for Ideal nodes used in String instrinsic code.
953 class StrIntrinsicNode: public Node {
954 public:
955 StrIntrinsicNode(Node* control, Node* char_array_mem,
956 Node* s1, Node* c1, Node* s2, Node* c2):
957 Node(control, char_array_mem, s1, c1, s2, c2) {
958 }
959
960 StrIntrinsicNode(Node* control, Node* char_array_mem,
961 Node* s1, Node* s2, Node* c):
962 Node(control, char_array_mem, s1, s2, c) {
963 }
964
965 StrIntrinsicNode(Node* control, Node* char_array_mem,
966 Node* s1, Node* s2):
967 Node(control, char_array_mem, s1, s2) {
968 }
969
970 virtual bool depends_only_on_test() const { return false; }
971 virtual const TypePtr* adr_type() const { return TypeAryPtr::CHARS; }
972 virtual uint match_edge(uint idx) const;
973 virtual uint ideal_reg() const { return Op_RegI; }
974 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
975 virtual const Type *Value(PhaseTransform *phase) const;
976 };
977
978 //------------------------------StrComp-------------------------------------
979 class StrCompNode: public StrIntrinsicNode {
980 public:
981 StrCompNode(Node* control, Node* char_array_mem,
982 Node* s1, Node* c1, Node* s2, Node* c2):
983 StrIntrinsicNode(control, char_array_mem, s1, c1, s2, c2) {};
984 virtual int Opcode() const;
985 virtual const Type* bottom_type() const { return TypeInt::INT; }
986 };
987
988 //------------------------------StrEquals-------------------------------------
989 class StrEqualsNode: public StrIntrinsicNode {
990 public:
991 StrEqualsNode(Node* control, Node* char_array_mem,
992 Node* s1, Node* s2, Node* c):
993 StrIntrinsicNode(control, char_array_mem, s1, s2, c) {};
994 virtual int Opcode() const;
995 virtual const Type* bottom_type() const { return TypeInt::BOOL; }
996 };
997
998 //------------------------------StrIndexOf-------------------------------------
999 class StrIndexOfNode: public StrIntrinsicNode {
1000 public:
1001 StrIndexOfNode(Node* control, Node* char_array_mem,
1002 Node* s1, Node* c1, Node* s2, Node* c2):
1003 StrIntrinsicNode(control, char_array_mem, s1, c1, s2, c2) {};
1004 virtual int Opcode() const;
1005 virtual const Type* bottom_type() const { return TypeInt::INT; }
1006 };
1007
1008 //------------------------------AryEq---------------------------------------
1009 class AryEqNode: public StrIntrinsicNode {
1010 public:
1011 AryEqNode(Node* control, Node* char_array_mem, Node* s1, Node* s2):
1012 StrIntrinsicNode(control, char_array_mem, s1, s2) {};
1013 virtual int Opcode() const;
1014 virtual const Type* bottom_type() const { return TypeInt::BOOL; }
1015 };
1016
1017
1018 //------------------------------EncodeISOArray--------------------------------
1019 // encode char[] to byte[] in ISO_8859_1
1020 class EncodeISOArrayNode: public Node {
1021 public:
1022 EncodeISOArrayNode(Node *control, Node* arymem, Node* s1, Node* s2, Node* c): Node(control, arymem, s1, s2, c) {};
1023 virtual int Opcode() const;
1024 virtual bool depends_only_on_test() const { return false; }
1025 virtual const Type* bottom_type() const { return TypeInt::INT; }
1026 virtual const TypePtr* adr_type() const { return TypePtr::BOTTOM; }
1027 virtual uint match_edge(uint idx) const;
1028 virtual uint ideal_reg() const { return Op_RegI; }
1029 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
1030 virtual const Type *Value(PhaseTransform *phase) const;
1031 };
1032
1033 //------------------------------MemBar-----------------------------------------
1034 // There are different flavors of Memory Barriers to match the Java Memory
1035 // Model. Monitor-enter and volatile-load act as Aquires: no following ref
1036 // can be moved to before them. We insert a MemBar-Acquire after a FastLock or
1037 // volatile-load. Monitor-exit and volatile-store act as Release: no
1038 // preceding ref can be moved to after them. We insert a MemBar-Release
1039 // before a FastUnlock or volatile-store. All volatiles need to be
1040 // serialized, so we follow all volatile-stores with a MemBar-Volatile to
1041 // separate it from any following volatile-load.
1042 class MemBarNode: public MultiNode {
1043 virtual uint hash() const ; // { return NO_HASH; }
1044 virtual uint cmp( const Node &n ) const ; // Always fail, except on self
1045
1046 virtual uint size_of() const { return sizeof(*this); }
1047 // Memory type this node is serializing. Usually either rawptr or bottom.
1048 const TypePtr* _adr_type;
1049
1050 // How is this membar related to a nearby memory access?
1051 enum {
1052 Standalone,
1053 TrailingLoad,
1054 TrailingStore,
1055 LeadingStore,
1056 TrailingLoadStore,
1057 LeadingLoadStore
1058 } _kind;
1059
1060 #ifdef ASSERT
1061 uint _pair_idx;
1062 #endif
1063
1064 public:
1065 enum {
1066 Precedent = TypeFunc::Parms // optional edge to force precedence
1067 };
1068 MemBarNode(Compile* C, int alias_idx, Node* precedent);
1069 virtual int Opcode() const = 0;
1070 virtual const class TypePtr *adr_type() const { return _adr_type; }
1071 virtual const Type *Value( PhaseTransform *phase ) const;
1072 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
1073 virtual uint match_edge(uint idx) const { return 0; }
1074 virtual const Type *bottom_type() const { return TypeTuple::MEMBAR; }
1075 virtual Node *match( const ProjNode *proj, const Matcher *m );
1076 // Factory method. Builds a wide or narrow membar.
1077 // Optional 'precedent' becomes an extra edge if not null.
1078 static MemBarNode* make(Compile* C, int opcode,
1079 int alias_idx = Compile::AliasIdxBot,
1080 Node* precedent = NULL);
1081
1082 MemBarNode* trailing_membar() const;
1083 MemBarNode* leading_membar() const;
1084
1085 void set_trailing_load() { _kind = TrailingLoad; }
1086 bool trailing_load() const { return _kind == TrailingLoad; }
1087 bool trailing_store() const { return _kind == TrailingStore; }
1088 bool leading_store() const { return _kind == LeadingStore; }
1089 bool trailing_load_store() const { return _kind == TrailingLoadStore; }
1090 bool leading_load_store() const { return _kind == LeadingLoadStore; }
1091 bool trailing() const { return _kind == TrailingLoad || _kind == TrailingStore || _kind == TrailingLoadStore; }
1092 bool leading() const { return _kind == LeadingStore || _kind == LeadingLoadStore; }
1093 bool standalone() const { return _kind == Standalone; }
1094
1095 static void set_store_pair(MemBarNode* leading, MemBarNode* trailing);
1096 static void set_load_store_pair(MemBarNode* leading, MemBarNode* trailing);
1097
1098 void remove(PhaseIterGVN *igvn);
1099 };
1100
1101 // "Acquire" - no following ref can move before (but earlier refs can
1102 // follow, like an early Load stalled in cache). Requires multi-cpu
1103 // visibility. Inserted after a volatile load.
1104 class MemBarAcquireNode: public MemBarNode {
1105 public:
1106 MemBarAcquireNode(Compile* C, int alias_idx, Node* precedent)
1107 : MemBarNode(C, alias_idx, precedent) {}
1108 virtual int Opcode() const;
1109 };
1110
1111 // "Acquire" - no following ref can move before (but earlier refs can
1112 // follow, like an early Load stalled in cache). Requires multi-cpu
1113 // visibility. Inserted independ of any load, as required
1114 // for intrinsic sun.misc.Unsafe.loadFence().
1115 class LoadFenceNode: public MemBarNode {
1116 public:
1117 LoadFenceNode(Compile* C, int alias_idx, Node* precedent)
1118 : MemBarNode(C, alias_idx, precedent) {}
1119 virtual int Opcode() const;
1120 };
1121
1122 // "Release" - no earlier ref can move after (but later refs can move
1123 // up, like a speculative pipelined cache-hitting Load). Requires
1124 // multi-cpu visibility. Inserted before a volatile store.
1125 class MemBarReleaseNode: public MemBarNode {
1126 public:
1127 MemBarReleaseNode(Compile* C, int alias_idx, Node* precedent)
1128 : MemBarNode(C, alias_idx, precedent) {}
1129 virtual int Opcode() const;
1130 };
1131
1132 // "Release" - no earlier ref can move after (but later refs can move
1133 // up, like a speculative pipelined cache-hitting Load). Requires
1134 // multi-cpu visibility. Inserted independent of any store, as required
1135 // for intrinsic sun.misc.Unsafe.storeFence().
1136 class StoreFenceNode: public MemBarNode {
1137 public:
1138 StoreFenceNode(Compile* C, int alias_idx, Node* precedent)
1139 : MemBarNode(C, alias_idx, precedent) {}
1140 virtual int Opcode() const;
1141 };
1142
1143 // "Acquire" - no following ref can move before (but earlier refs can
1144 // follow, like an early Load stalled in cache). Requires multi-cpu
1145 // visibility. Inserted after a FastLock.
1146 class MemBarAcquireLockNode: public MemBarNode {
1147 public:
1148 MemBarAcquireLockNode(Compile* C, int alias_idx, Node* precedent)
1149 : MemBarNode(C, alias_idx, precedent) {}
1150 virtual int Opcode() const;
1151 };
1152
1153 // "Release" - no earlier ref can move after (but later refs can move
1154 // up, like a speculative pipelined cache-hitting Load). Requires
1155 // multi-cpu visibility. Inserted before a FastUnLock.
1156 class MemBarReleaseLockNode: public MemBarNode {
1157 public:
1158 MemBarReleaseLockNode(Compile* C, int alias_idx, Node* precedent)
1159 : MemBarNode(C, alias_idx, precedent) {}
1160 virtual int Opcode() const;
1161 };
1162
1163 class MemBarStoreStoreNode: public MemBarNode {
1164 public:
1165 MemBarStoreStoreNode(Compile* C, int alias_idx, Node* precedent)
1166 : MemBarNode(C, alias_idx, precedent) {
1167 init_class_id(Class_MemBarStoreStore);
1168 }
1169 virtual int Opcode() const;
1170 };
1171
1172 // Ordering between a volatile store and a following volatile load.
1173 // Requires multi-CPU visibility?
1174 class MemBarVolatileNode: public MemBarNode {
1175 public:
1176 MemBarVolatileNode(Compile* C, int alias_idx, Node* precedent)
1177 : MemBarNode(C, alias_idx, precedent) {}
1178 virtual int Opcode() const;
1179 };
1180
1181 // Ordering within the same CPU. Used to order unsafe memory references
1182 // inside the compiler when we lack alias info. Not needed "outside" the
1183 // compiler because the CPU does all the ordering for us.
1184 class MemBarCPUOrderNode: public MemBarNode {
1185 public:
1186 MemBarCPUOrderNode(Compile* C, int alias_idx, Node* precedent)
1187 : MemBarNode(C, alias_idx, precedent) {}
1188 virtual int Opcode() const;
1189 virtual uint ideal_reg() const { return 0; } // not matched in the AD file
1190 };
1191
1192 // Isolation of object setup after an AllocateNode and before next safepoint.
1193 // (See comment in memnode.cpp near InitializeNode::InitializeNode for semantics.)
1194 class InitializeNode: public MemBarNode {
1195 friend class AllocateNode;
1196
1197 enum {
1198 Incomplete = 0,
1199 Complete = 1,
1200 WithArraycopy = 2
1201 };
1202 int _is_complete;
1203
1204 bool _does_not_escape;
1205
1206 public:
1207 enum {
1208 Control = TypeFunc::Control,
1209 Memory = TypeFunc::Memory, // MergeMem for states affected by this op
1210 RawAddress = TypeFunc::Parms+0, // the newly-allocated raw address
1211 RawStores = TypeFunc::Parms+1 // zero or more stores (or TOP)
1212 };
1213
1214 InitializeNode(Compile* C, int adr_type, Node* rawoop);
1215 virtual int Opcode() const;
1216 virtual uint size_of() const { return sizeof(*this); }
1217 virtual uint ideal_reg() const { return 0; } // not matched in the AD file
1218 virtual const RegMask &in_RegMask(uint) const; // mask for RawAddress
1219
1220 // Manage incoming memory edges via a MergeMem on in(Memory):
1221 Node* memory(uint alias_idx);
1222
1223 // The raw memory edge coming directly from the Allocation.
1224 // The contents of this memory are *always* all-zero-bits.
1225 Node* zero_memory() { return memory(Compile::AliasIdxRaw); }
1226
1227 // Return the corresponding allocation for this initialization (or null if none).
1228 // (Note: Both InitializeNode::allocation and AllocateNode::initialization
1229 // are defined in graphKit.cpp, which sets up the bidirectional relation.)
1230 AllocateNode* allocation();
1231
1232 // Anything other than zeroing in this init?
1233 bool is_non_zero();
1234
1235 // An InitializeNode must completed before macro expansion is done.
1236 // Completion requires that the AllocateNode must be followed by
1237 // initialization of the new memory to zero, then to any initializers.
1238 bool is_complete() { return _is_complete != Incomplete; }
1239 bool is_complete_with_arraycopy() { return (_is_complete & WithArraycopy) != 0; }
1240
1241 // Mark complete. (Must not yet be complete.)
1242 void set_complete(PhaseGVN* phase);
1243 void set_complete_with_arraycopy() { _is_complete = Complete | WithArraycopy; }
1244
1245 bool does_not_escape() { return _does_not_escape; }
1246 void set_does_not_escape() { _does_not_escape = true; }
1247
1248 #ifdef ASSERT
1249 // ensure all non-degenerate stores are ordered and non-overlapping
1250 bool stores_are_sane(PhaseTransform* phase);
1251 #endif //ASSERT
1252
1253 // See if this store can be captured; return offset where it initializes.
1254 // Return 0 if the store cannot be moved (any sort of problem).
1255 intptr_t can_capture_store(StoreNode* st, PhaseTransform* phase, bool can_reshape);
1256
1257 // Capture another store; reformat it to write my internal raw memory.
1258 // Return the captured copy, else NULL if there is some sort of problem.
1259 Node* capture_store(StoreNode* st, intptr_t start, PhaseTransform* phase, bool can_reshape);
1260
1261 // Find captured store which corresponds to the range [start..start+size).
1262 // Return my own memory projection (meaning the initial zero bits)
1263 // if there is no such store. Return NULL if there is a problem.
1264 Node* find_captured_store(intptr_t start, int size_in_bytes, PhaseTransform* phase);
1265
1266 // Called when the associated AllocateNode is expanded into CFG.
1267 Node* complete_stores(Node* rawctl, Node* rawmem, Node* rawptr,
1268 intptr_t header_size, Node* size_in_bytes,
1269 PhaseGVN* phase);
1270
1271 private:
1272 void remove_extra_zeroes();
1273
1274 // Find out where a captured store should be placed (or already is placed).
1275 int captured_store_insertion_point(intptr_t start, int size_in_bytes,
1276 PhaseTransform* phase);
1277
1278 static intptr_t get_store_offset(Node* st, PhaseTransform* phase);
1279
1280 Node* make_raw_address(intptr_t offset, PhaseTransform* phase);
1281
1282 bool detect_init_independence(Node* n, int& count);
1283
1284 void coalesce_subword_stores(intptr_t header_size, Node* size_in_bytes,
1285 PhaseGVN* phase);
1286
1287 intptr_t find_next_fullword_store(uint i, PhaseGVN* phase);
1288 };
1289
1290 //------------------------------MergeMem---------------------------------------
1291 // (See comment in memnode.cpp near MergeMemNode::MergeMemNode for semantics.)
1292 class MergeMemNode: public Node {
1293 virtual uint hash() const ; // { return NO_HASH; }
1294 virtual uint cmp( const Node &n ) const ; // Always fail, except on self
1295 friend class MergeMemStream;
1296 MergeMemNode(Node* def); // clients use MergeMemNode::make
1297
1298 public:
1299 // If the input is a whole memory state, clone it with all its slices intact.
1300 // Otherwise, make a new memory state with just that base memory input.
1301 // In either case, the result is a newly created MergeMem.
1302 static MergeMemNode* make(Compile* C, Node* base_memory);
1303
1304 virtual int Opcode() const;
1305 virtual Node *Identity( PhaseTransform *phase );
1306 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
1307 virtual uint ideal_reg() const { return NotAMachineReg; }
1308 virtual uint match_edge(uint idx) const { return 0; }
1309 virtual const RegMask &out_RegMask() const;
1310 virtual const Type *bottom_type() const { return Type::MEMORY; }
1311 virtual const TypePtr *adr_type() const { return TypePtr::BOTTOM; }
1312 // sparse accessors
1313 // Fetch the previously stored "set_memory_at", or else the base memory.
1314 // (Caller should clone it if it is a phi-nest.)
1315 Node* memory_at(uint alias_idx) const;
1316 // set the memory, regardless of its previous value
1317 void set_memory_at(uint alias_idx, Node* n);
1318 // the "base" is the memory that provides the non-finite support
1319 Node* base_memory() const { return in(Compile::AliasIdxBot); }
1320 // warning: setting the base can implicitly set any of the other slices too
1321 void set_base_memory(Node* def);
1322 // sentinel value which denotes a copy of the base memory:
1323 Node* empty_memory() const { return in(Compile::AliasIdxTop); }
1324 static Node* make_empty_memory(); // where the sentinel comes from
1325 bool is_empty_memory(Node* n) const { assert((n == empty_memory()) == n->is_top(), "sanity"); return n->is_top(); }
1326 // hook for the iterator, to perform any necessary setup
1327 void iteration_setup(const MergeMemNode* other = NULL);
1328 // push sentinels until I am at least as long as the other (semantic no-op)
1329 void grow_to_match(const MergeMemNode* other);
1330 bool verify_sparse() const PRODUCT_RETURN0;
1331 #ifndef PRODUCT
1332 virtual void dump_spec(outputStream *st) const;
1333 #endif
1334 };
1335
1336 class MergeMemStream : public StackObj {
1337 private:
1338 MergeMemNode* _mm;
1339 const MergeMemNode* _mm2; // optional second guy, contributes non-empty iterations
1340 Node* _mm_base; // loop-invariant base memory of _mm
1341 int _idx;
1342 int _cnt;
1343 Node* _mem;
1344 Node* _mem2;
1345 int _cnt2;
1346
1347 void init(MergeMemNode* mm, const MergeMemNode* mm2 = NULL) {
1348 // subsume_node will break sparseness at times, whenever a memory slice
1349 // folds down to a copy of the base ("fat") memory. In such a case,
1350 // the raw edge will update to base, although it should be top.
1351 // This iterator will recognize either top or base_memory as an
1352 // "empty" slice. See is_empty, is_empty2, and next below.
1353 //
1354 // The sparseness property is repaired in MergeMemNode::Ideal.
1355 // As long as access to a MergeMem goes through this iterator
1356 // or the memory_at accessor, flaws in the sparseness will
1357 // never be observed.
1358 //
1359 // Also, iteration_setup repairs sparseness.
1360 assert(mm->verify_sparse(), "please, no dups of base");
1361 assert(mm2==NULL || mm2->verify_sparse(), "please, no dups of base");
1362
1363 _mm = mm;
1364 _mm_base = mm->base_memory();
1365 _mm2 = mm2;
1366 _cnt = mm->req();
1367 _idx = Compile::AliasIdxBot-1; // start at the base memory
1368 _mem = NULL;
1369 _mem2 = NULL;
1370 }
1371
1372 #ifdef ASSERT
1373 Node* check_memory() const {
1374 if (at_base_memory())
1375 return _mm->base_memory();
1376 else if ((uint)_idx < _mm->req() && !_mm->in(_idx)->is_top())
1377 return _mm->memory_at(_idx);
1378 else
1379 return _mm_base;
1380 }
1381 Node* check_memory2() const {
1382 return at_base_memory()? _mm2->base_memory(): _mm2->memory_at(_idx);
1383 }
1384 #endif
1385
1386 static bool match_memory(Node* mem, const MergeMemNode* mm, int idx) PRODUCT_RETURN0;
1387 void assert_synch() const {
1388 assert(!_mem || _idx >= _cnt || match_memory(_mem, _mm, _idx),
1389 "no side-effects except through the stream");
1390 }
1391
1392 public:
1393
1394 // expected usages:
1395 // for (MergeMemStream mms(mem->is_MergeMem()); next_non_empty(); ) { ... }
1396 // for (MergeMemStream mms(mem1, mem2); next_non_empty2(); ) { ... }
1397
1398 // iterate over one merge
1399 MergeMemStream(MergeMemNode* mm) {
1400 mm->iteration_setup();
1401 init(mm);
1402 debug_only(_cnt2 = 999);
1403 }
1404 // iterate in parallel over two merges
1405 // only iterates through non-empty elements of mm2
1406 MergeMemStream(MergeMemNode* mm, const MergeMemNode* mm2) {
1407 assert(mm2, "second argument must be a MergeMem also");
1408 ((MergeMemNode*)mm2)->iteration_setup(); // update hidden state
1409 mm->iteration_setup(mm2);
1410 init(mm, mm2);
1411 _cnt2 = mm2->req();
1412 }
1413 #ifdef ASSERT
1414 ~MergeMemStream() {
1415 assert_synch();
1416 }
1417 #endif
1418
1419 MergeMemNode* all_memory() const {
1420 return _mm;
1421 }
1422 Node* base_memory() const {
1423 assert(_mm_base == _mm->base_memory(), "no update to base memory, please");
1424 return _mm_base;
1425 }
1426 const MergeMemNode* all_memory2() const {
1427 assert(_mm2 != NULL, "");
1428 return _mm2;
1429 }
1430 bool at_base_memory() const {
1431 return _idx == Compile::AliasIdxBot;
1432 }
1433 int alias_idx() const {
1434 assert(_mem, "must call next 1st");
1435 return _idx;
1436 }
1437
1438 const TypePtr* adr_type() const {
1439 return Compile::current()->get_adr_type(alias_idx());
1440 }
1441
1442 const TypePtr* adr_type(Compile* C) const {
1443 return C->get_adr_type(alias_idx());
1444 }
1445 bool is_empty() const {
1446 assert(_mem, "must call next 1st");
1447 assert(_mem->is_top() == (_mem==_mm->empty_memory()), "correct sentinel");
1448 return _mem->is_top();
1449 }
1450 bool is_empty2() const {
1451 assert(_mem2, "must call next 1st");
1452 assert(_mem2->is_top() == (_mem2==_mm2->empty_memory()), "correct sentinel");
1453 return _mem2->is_top();
1454 }
1455 Node* memory() const {
1456 assert(!is_empty(), "must not be empty");
1457 assert_synch();
1458 return _mem;
1459 }
1460 // get the current memory, regardless of empty or non-empty status
1461 Node* force_memory() const {
1462 assert(!is_empty() || !at_base_memory(), "");
1463 // Use _mm_base to defend against updates to _mem->base_memory().
1464 Node *mem = _mem->is_top() ? _mm_base : _mem;
1465 assert(mem == check_memory(), "");
1466 return mem;
1467 }
1468 Node* memory2() const {
1469 assert(_mem2 == check_memory2(), "");
1470 return _mem2;
1471 }
1472 void set_memory(Node* mem) {
1473 if (at_base_memory()) {
1474 // Note that this does not change the invariant _mm_base.
1475 _mm->set_base_memory(mem);
1476 } else {
1477 _mm->set_memory_at(_idx, mem);
1478 }
1479 _mem = mem;
1480 assert_synch();
1481 }
1482
1483 // Recover from a side effect to the MergeMemNode.
1484 void set_memory() {
1485 _mem = _mm->in(_idx);
1486 }
1487
1488 bool next() { return next(false); }
1489 bool next2() { return next(true); }
1490
1491 bool next_non_empty() { return next_non_empty(false); }
1492 bool next_non_empty2() { return next_non_empty(true); }
1493 // next_non_empty2 can yield states where is_empty() is true
1494
1495 private:
1496 // find the next item, which might be empty
1497 bool next(bool have_mm2) {
1498 assert((_mm2 != NULL) == have_mm2, "use other next");
1499 assert_synch();
1500 if (++_idx < _cnt) {
1501 // Note: This iterator allows _mm to be non-sparse.
1502 // It behaves the same whether _mem is top or base_memory.
1503 _mem = _mm->in(_idx);
1504 if (have_mm2)
1505 _mem2 = _mm2->in((_idx < _cnt2) ? _idx : Compile::AliasIdxTop);
1506 return true;
1507 }
1508 return false;
1509 }
1510
1511 // find the next non-empty item
1512 bool next_non_empty(bool have_mm2) {
1513 while (next(have_mm2)) {
1514 if (!is_empty()) {
1515 // make sure _mem2 is filled in sensibly
1516 if (have_mm2 && _mem2->is_top()) _mem2 = _mm2->base_memory();
1517 return true;
1518 } else if (have_mm2 && !is_empty2()) {
1519 return true; // is_empty() == true
1520 }
1521 }
1522 return false;
1523 }
1524 };
1525
1526 //------------------------------Prefetch---------------------------------------
1527
1528 // Non-faulting prefetch load. Prefetch for many reads.
1529 class PrefetchReadNode : public Node {
1530 public:
1531 PrefetchReadNode(Node *abio, Node *adr) : Node(0,abio,adr) {}
1532 virtual int Opcode() const;
1533 virtual uint ideal_reg() const { return NotAMachineReg; }
1534 virtual uint match_edge(uint idx) const { return idx==2; }
1535 virtual const Type *bottom_type() const { return Type::ABIO; }
1536 };
1537
1538 // Non-faulting prefetch load. Prefetch for many reads & many writes.
1539 class PrefetchWriteNode : public Node {
1540 public:
1541 PrefetchWriteNode(Node *abio, Node *adr) : Node(0,abio,adr) {}
1542 virtual int Opcode() const;
1543 virtual uint ideal_reg() const { return NotAMachineReg; }
1544 virtual uint match_edge(uint idx) const { return idx==2; }
1545 virtual const Type *bottom_type() const { return Type::ABIO; }
1546 };
1547
1548 // Allocation prefetch which may fault, TLAB size have to be adjusted.
1549 class PrefetchAllocationNode : public Node {
1550 public:
1551 PrefetchAllocationNode(Node *mem, Node *adr) : Node(0,mem,adr) {}
1552 virtual int Opcode() const;
1553 virtual uint ideal_reg() const { return NotAMachineReg; }
1554 virtual uint match_edge(uint idx) const { return idx==2; }
1555 virtual const Type *bottom_type() const { return ( AllocatePrefetchStyle == 3 ) ? Type::MEMORY : Type::ABIO; }
1556 };
1557
1558 #endif // SHARE_VM_OPTO_MEMNODE_HPP