1 /*
2 * Copyright (c) 1997, 2015, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
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11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
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23 */
24
25 #ifndef SHARE_VM_OPTO_MEMNODE_HPP
26 #define SHARE_VM_OPTO_MEMNODE_HPP
27
28 #include "opto/multnode.hpp"
29 #include "opto/node.hpp"
30 #include "opto/opcodes.hpp"
31 #include "opto/type.hpp"
32
33 // Portions of code courtesy of Clifford Click
34
35 class MultiNode;
36 class PhaseCCP;
37 class PhaseTransform;
38
39 //------------------------------MemNode----------------------------------------
40 // Load or Store, possibly throwing a NULL pointer exception
41 class MemNode : public Node {
42 private:
43 bool _unaligned;
44 protected:
45 #ifdef ASSERT
46 const TypePtr* _adr_type; // What kind of memory is being addressed?
47 #endif
48 virtual uint size_of() const;
49 public:
50 enum { Control, // When is it safe to do this load?
51 Memory, // Chunk of memory is being loaded from
52 Address, // Actually address, derived from base
53 ValueIn, // Value to store
54 OopStore // Preceeding oop store, only in StoreCM
55 };
56 typedef enum { unordered = 0,
57 acquire, // Load has to acquire or be succeeded by MemBarAcquire.
58 release // Store has to release or be preceded by MemBarRelease.
59 } MemOrd;
60 protected:
61 MemNode( Node *c0, Node *c1, Node *c2, const TypePtr* at )
62 : Node(c0,c1,c2 ), _unaligned(false) {
63 init_class_id(Class_Mem);
64 debug_only(_adr_type=at; adr_type();)
65 }
66 MemNode( Node *c0, Node *c1, Node *c2, const TypePtr* at, Node *c3 )
67 : Node(c0,c1,c2,c3), _unaligned(false) {
68 init_class_id(Class_Mem);
69 debug_only(_adr_type=at; adr_type();)
70 }
71 MemNode( Node *c0, Node *c1, Node *c2, const TypePtr* at, Node *c3, Node *c4)
72 : Node(c0,c1,c2,c3,c4), _unaligned(false) {
73 init_class_id(Class_Mem);
74 debug_only(_adr_type=at; adr_type();)
75 }
76
77 virtual Node* find_previous_arraycopy(PhaseTransform* phase, Node* ld_alloc, Node*& mem, bool can_see_stored_value) const { return NULL; }
78
79 public:
80 // Helpers for the optimizer. Documented in memnode.cpp.
81 static bool detect_ptr_independence(Node* p1, AllocateNode* a1,
82 Node* p2, AllocateNode* a2,
83 PhaseTransform* phase);
84 static bool adr_phi_is_loop_invariant(Node* adr_phi, Node* cast);
85
86 static Node *optimize_simple_memory_chain(Node *mchain, const TypeOopPtr *t_oop, Node *load, PhaseGVN *phase);
87 static Node *optimize_memory_chain(Node *mchain, const TypePtr *t_adr, Node *load, PhaseGVN *phase);
88 // This one should probably be a phase-specific function:
89 static bool all_controls_dominate(Node* dom, Node* sub);
90
91 virtual const class TypePtr *adr_type() const; // returns bottom_type of address
92
93 // Shared code for Ideal methods:
94 Node *Ideal_common(PhaseGVN *phase, bool can_reshape); // Return -1 for short-circuit NULL.
95
96 // Helper function for adr_type() implementations.
97 static const TypePtr* calculate_adr_type(const Type* t, const TypePtr* cross_check = NULL);
98
99 // Raw access function, to allow copying of adr_type efficiently in
100 // product builds and retain the debug info for debug builds.
101 const TypePtr *raw_adr_type() const {
102 #ifdef ASSERT
103 return _adr_type;
104 #else
105 return 0;
106 #endif
107 }
108
109 // Map a load or store opcode to its corresponding store opcode.
110 // (Return -1 if unknown.)
111 virtual int store_Opcode() const { return -1; }
112
113 // What is the type of the value in memory? (T_VOID mean "unspecified".)
114 virtual BasicType memory_type() const = 0;
115 virtual int memory_size() const {
116 #ifdef ASSERT
117 return type2aelembytes(memory_type(), true);
118 #else
119 return type2aelembytes(memory_type());
120 #endif
121 }
122
123 // Search through memory states which precede this node (load or store).
124 // Look for an exact match for the address, with no intervening
125 // aliased stores.
126 Node* find_previous_store(PhaseTransform* phase);
127
128 // Can this node (load or store) accurately see a stored value in
129 // the given memory state? (The state may or may not be in(Memory).)
130 Node* can_see_stored_value(Node* st, PhaseTransform* phase) const;
131
132 void set_unaligned() { _unaligned = true; }
133 bool is_unaligned() const { return _unaligned; }
134
135 #ifndef PRODUCT
136 static void dump_adr_type(const Node* mem, const TypePtr* adr_type, outputStream *st);
137 virtual void dump_spec(outputStream *st) const;
138 #endif
139 };
140
141 //------------------------------LoadNode---------------------------------------
142 // Load value; requires Memory and Address
143 class LoadNode : public MemNode {
144 public:
145 // Some loads (from unsafe) should be pinned: they don't depend only
146 // on the dominating test. The boolean field _depends_only_on_test
147 // below records whether that node depends only on the dominating
148 // test.
149 // Methods used to build LoadNodes pass an argument of type enum
150 // ControlDependency instead of a boolean because those methods
151 // typically have multiple boolean parameters with default values:
152 // passing the wrong boolean to one of these parameters by mistake
153 // goes easily unnoticed. Using an enum, the compiler can check that
154 // the type of a value and the type of the parameter match.
155 enum ControlDependency {
156 Pinned,
157 DependsOnlyOnTest
158 };
159 private:
160 // LoadNode::hash() doesn't take the _depends_only_on_test field
161 // into account: If the graph already has a non-pinned LoadNode and
162 // we add a pinned LoadNode with the same inputs, it's safe for GVN
163 // to replace the pinned LoadNode with the non-pinned LoadNode,
164 // otherwise it wouldn't be safe to have a non pinned LoadNode with
165 // those inputs in the first place. If the graph already has a
166 // pinned LoadNode and we add a non pinned LoadNode with the same
167 // inputs, it's safe (but suboptimal) for GVN to replace the
168 // non-pinned LoadNode by the pinned LoadNode.
169 bool _depends_only_on_test;
170
171 // On platforms with weak memory ordering (e.g., PPC, Ia64) we distinguish
172 // loads that can be reordered, and such requiring acquire semantics to
173 // adhere to the Java specification. The required behaviour is stored in
174 // this field.
175 const MemOrd _mo;
176
177 protected:
178 virtual uint cmp(const Node &n) const;
179 virtual uint size_of() const; // Size is bigger
180 // Should LoadNode::Ideal() attempt to remove control edges?
181 virtual bool can_remove_control() const;
182 const Type* const _type; // What kind of value is loaded?
183
184 virtual Node* find_previous_arraycopy(PhaseTransform* phase, Node* ld_alloc, Node*& mem, bool can_see_stored_value) const;
185 public:
186
187 LoadNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const Type *rt, MemOrd mo, ControlDependency control_dependency)
188 : MemNode(c,mem,adr,at), _type(rt), _mo(mo), _depends_only_on_test(control_dependency == DependsOnlyOnTest) {
189 init_class_id(Class_Load);
190 }
191 inline bool is_unordered() const { return !is_acquire(); }
192 inline bool is_acquire() const {
193 assert(_mo == unordered || _mo == acquire, "unexpected");
194 return _mo == acquire;
195 }
196
197 // Polymorphic factory method:
198 static Node* make(PhaseGVN& gvn, Node *c, Node *mem, Node *adr,
199 const TypePtr* at, const Type *rt, BasicType bt,
200 MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest);
201
202 virtual uint hash() const; // Check the type
203
204 // Handle algebraic identities here. If we have an identity, return the Node
205 // we are equivalent to. We look for Load of a Store.
206 virtual Node *Identity( PhaseTransform *phase );
207
208 // If the load is from Field memory and the pointer is non-null, it might be possible to
209 // zero out the control input.
210 // If the offset is constant and the base is an object allocation,
211 // try to hook me up to the exact initializing store.
212 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
213
214 // Split instance field load through Phi.
215 Node* split_through_phi(PhaseGVN *phase);
216
217 // Recover original value from boxed values
218 Node *eliminate_autobox(PhaseGVN *phase);
219
220 // Compute a new Type for this node. Basically we just do the pre-check,
221 // then call the virtual add() to set the type.
222 virtual const Type *Value( PhaseTransform *phase ) const;
223
224 // Common methods for LoadKlass and LoadNKlass nodes.
225 const Type *klass_value_common( PhaseTransform *phase ) const;
226 Node *klass_identity_common( PhaseTransform *phase );
227
228 virtual uint ideal_reg() const;
229 virtual const Type *bottom_type() const;
230 // Following method is copied from TypeNode:
231 void set_type(const Type* t) {
232 assert(t != NULL, "sanity");
233 debug_only(uint check_hash = (VerifyHashTableKeys && _hash_lock) ? hash() : NO_HASH);
234 *(const Type**)&_type = t; // cast away const-ness
235 // If this node is in the hash table, make sure it doesn't need a rehash.
236 assert(check_hash == NO_HASH || check_hash == hash(), "type change must preserve hash code");
237 }
238 const Type* type() const { assert(_type != NULL, "sanity"); return _type; };
239
240 // Do not match memory edge
241 virtual uint match_edge(uint idx) const;
242
243 // Map a load opcode to its corresponding store opcode.
244 virtual int store_Opcode() const = 0;
245
246 // Check if the load's memory input is a Phi node with the same control.
247 bool is_instance_field_load_with_local_phi(Node* ctrl);
248
249 #ifndef PRODUCT
250 virtual void dump_spec(outputStream *st) const;
251 #endif
252 #ifdef ASSERT
253 // Helper function to allow a raw load without control edge for some cases
254 static bool is_immutable_value(Node* adr);
255 #endif
256 protected:
257 const Type* load_array_final_field(const TypeKlassPtr *tkls,
258 ciKlass* klass) const;
259
260 Node* can_see_arraycopy_value(Node* st, PhaseTransform* phase) const;
261
262 // depends_only_on_test is almost always true, and needs to be almost always
263 // true to enable key hoisting & commoning optimizations. However, for the
264 // special case of RawPtr loads from TLS top & end, and other loads performed by
265 // GC barriers, the control edge carries the dependence preventing hoisting past
266 // a Safepoint instead of the memory edge. (An unfortunate consequence of having
267 // Safepoints not set Raw Memory; itself an unfortunate consequence of having Nodes
268 // which produce results (new raw memory state) inside of loops preventing all
269 // manner of other optimizations). Basically, it's ugly but so is the alternative.
270 // See comment in macro.cpp, around line 125 expand_allocate_common().
271 virtual bool depends_only_on_test() const { return adr_type() != TypeRawPtr::BOTTOM && _depends_only_on_test; }
272 };
273
274 //------------------------------LoadBNode--------------------------------------
275 // Load a byte (8bits signed) from memory
276 class LoadBNode : public LoadNode {
277 public:
278 LoadBNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeInt *ti, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
279 : LoadNode(c, mem, adr, at, ti, mo, control_dependency) {}
280 virtual int Opcode() const;
281 virtual uint ideal_reg() const { return Op_RegI; }
282 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
283 virtual const Type *Value(PhaseTransform *phase) const;
284 virtual int store_Opcode() const { return Op_StoreB; }
285 virtual BasicType memory_type() const { return T_BYTE; }
286 };
287
288 //------------------------------LoadUBNode-------------------------------------
289 // Load a unsigned byte (8bits unsigned) from memory
290 class LoadUBNode : public LoadNode {
291 public:
292 LoadUBNode(Node* c, Node* mem, Node* adr, const TypePtr* at, const TypeInt* ti, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
293 : LoadNode(c, mem, adr, at, ti, mo, control_dependency) {}
294 virtual int Opcode() const;
295 virtual uint ideal_reg() const { return Op_RegI; }
296 virtual Node* Ideal(PhaseGVN *phase, bool can_reshape);
297 virtual const Type *Value(PhaseTransform *phase) const;
298 virtual int store_Opcode() const { return Op_StoreB; }
299 virtual BasicType memory_type() const { return T_BYTE; }
300 };
301
302 //------------------------------LoadUSNode-------------------------------------
303 // Load an unsigned short/char (16bits unsigned) from memory
304 class LoadUSNode : public LoadNode {
305 public:
306 LoadUSNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeInt *ti, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
307 : LoadNode(c, mem, adr, at, ti, mo, control_dependency) {}
308 virtual int Opcode() const;
309 virtual uint ideal_reg() const { return Op_RegI; }
310 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
311 virtual const Type *Value(PhaseTransform *phase) const;
312 virtual int store_Opcode() const { return Op_StoreC; }
313 virtual BasicType memory_type() const { return T_CHAR; }
314 };
315
316 //------------------------------LoadSNode--------------------------------------
317 // Load a short (16bits signed) from memory
318 class LoadSNode : public LoadNode {
319 public:
320 LoadSNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeInt *ti, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
321 : LoadNode(c, mem, adr, at, ti, mo, control_dependency) {}
322 virtual int Opcode() const;
323 virtual uint ideal_reg() const { return Op_RegI; }
324 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
325 virtual const Type *Value(PhaseTransform *phase) const;
326 virtual int store_Opcode() const { return Op_StoreC; }
327 virtual BasicType memory_type() const { return T_SHORT; }
328 };
329
330 //------------------------------LoadINode--------------------------------------
331 // Load an integer from memory
332 class LoadINode : public LoadNode {
333 public:
334 LoadINode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeInt *ti, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
335 : LoadNode(c, mem, adr, at, ti, mo, control_dependency) {}
336 virtual int Opcode() const;
337 virtual uint ideal_reg() const { return Op_RegI; }
338 virtual int store_Opcode() const { return Op_StoreI; }
339 virtual BasicType memory_type() const { return T_INT; }
340 };
341
342 //------------------------------LoadRangeNode----------------------------------
343 // Load an array length from the array
344 class LoadRangeNode : public LoadINode {
345 public:
346 LoadRangeNode(Node *c, Node *mem, Node *adr, const TypeInt *ti = TypeInt::POS)
347 : LoadINode(c, mem, adr, TypeAryPtr::RANGE, ti, MemNode::unordered) {}
348 virtual int Opcode() const;
349 virtual const Type *Value( PhaseTransform *phase ) const;
350 virtual Node *Identity( PhaseTransform *phase );
351 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
352 };
353
354 //------------------------------LoadLNode--------------------------------------
355 // Load a long from memory
356 class LoadLNode : public LoadNode {
357 virtual uint hash() const { return LoadNode::hash() + _require_atomic_access; }
358 virtual uint cmp( const Node &n ) const {
359 return _require_atomic_access == ((LoadLNode&)n)._require_atomic_access
360 && LoadNode::cmp(n);
361 }
362 virtual uint size_of() const { return sizeof(*this); }
363 const bool _require_atomic_access; // is piecewise load forbidden?
364
365 public:
366 LoadLNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeLong *tl,
367 MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest, bool require_atomic_access = false)
368 : LoadNode(c, mem, adr, at, tl, mo, control_dependency), _require_atomic_access(require_atomic_access) {}
369 virtual int Opcode() const;
370 virtual uint ideal_reg() const { return Op_RegL; }
371 virtual int store_Opcode() const { return Op_StoreL; }
372 virtual BasicType memory_type() const { return T_LONG; }
373 bool require_atomic_access() const { return _require_atomic_access; }
374 static LoadLNode* make_atomic(Node* ctl, Node* mem, Node* adr, const TypePtr* adr_type,
375 const Type* rt, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest);
376 #ifndef PRODUCT
377 virtual void dump_spec(outputStream *st) const {
378 LoadNode::dump_spec(st);
379 if (_require_atomic_access) st->print(" Atomic!");
380 }
381 #endif
382 };
383
384 //------------------------------LoadL_unalignedNode----------------------------
385 // Load a long from unaligned memory
386 class LoadL_unalignedNode : public LoadLNode {
387 public:
388 LoadL_unalignedNode(Node *c, Node *mem, Node *adr, const TypePtr* at, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
389 : LoadLNode(c, mem, adr, at, TypeLong::LONG, mo, control_dependency) {}
390 virtual int Opcode() const;
391 };
392
393 //------------------------------LoadFNode--------------------------------------
394 // Load a float (64 bits) from memory
395 class LoadFNode : public LoadNode {
396 public:
397 LoadFNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const Type *t, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
398 : LoadNode(c, mem, adr, at, t, mo, control_dependency) {}
399 virtual int Opcode() const;
400 virtual uint ideal_reg() const { return Op_RegF; }
401 virtual int store_Opcode() const { return Op_StoreF; }
402 virtual BasicType memory_type() const { return T_FLOAT; }
403 };
404
405 //------------------------------LoadDNode--------------------------------------
406 // Load a double (64 bits) from memory
407 class LoadDNode : public LoadNode {
408 virtual uint hash() const { return LoadNode::hash() + _require_atomic_access; }
409 virtual uint cmp( const Node &n ) const {
410 return _require_atomic_access == ((LoadDNode&)n)._require_atomic_access
411 && LoadNode::cmp(n);
412 }
413 virtual uint size_of() const { return sizeof(*this); }
414 const bool _require_atomic_access; // is piecewise load forbidden?
415
416 public:
417 LoadDNode(Node *c, Node *mem, Node *adr, const TypePtr* at, const Type *t,
418 MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest, bool require_atomic_access = false)
419 : LoadNode(c, mem, adr, at, t, mo, control_dependency), _require_atomic_access(require_atomic_access) {}
420 virtual int Opcode() const;
421 virtual uint ideal_reg() const { return Op_RegD; }
422 virtual int store_Opcode() const { return Op_StoreD; }
423 virtual BasicType memory_type() const { return T_DOUBLE; }
424 bool require_atomic_access() const { return _require_atomic_access; }
425 static LoadDNode* make_atomic(Node* ctl, Node* mem, Node* adr, const TypePtr* adr_type,
426 const Type* rt, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest);
427 #ifndef PRODUCT
428 virtual void dump_spec(outputStream *st) const {
429 LoadNode::dump_spec(st);
430 if (_require_atomic_access) st->print(" Atomic!");
431 }
432 #endif
433 };
434
435 //------------------------------LoadD_unalignedNode----------------------------
436 // Load a double from unaligned memory
437 class LoadD_unalignedNode : public LoadDNode {
438 public:
439 LoadD_unalignedNode(Node *c, Node *mem, Node *adr, const TypePtr* at, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
440 : LoadDNode(c, mem, adr, at, Type::DOUBLE, mo, control_dependency) {}
441 virtual int Opcode() const;
442 };
443
444 //------------------------------LoadPNode--------------------------------------
445 // Load a pointer from memory (either object or array)
446 class LoadPNode : public LoadNode {
447 public:
448 LoadPNode(Node *c, Node *mem, Node *adr, const TypePtr *at, const TypePtr* t, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
449 : LoadNode(c, mem, adr, at, t, mo, control_dependency) {}
450 virtual int Opcode() const;
451 virtual uint ideal_reg() const { return Op_RegP; }
452 virtual int store_Opcode() const { return Op_StoreP; }
453 virtual BasicType memory_type() const { return T_ADDRESS; }
454 };
455
456
457 //------------------------------LoadNNode--------------------------------------
458 // Load a narrow oop from memory (either object or array)
459 class LoadNNode : public LoadNode {
460 public:
461 LoadNNode(Node *c, Node *mem, Node *adr, const TypePtr *at, const Type* t, MemOrd mo, ControlDependency control_dependency = DependsOnlyOnTest)
462 : LoadNode(c, mem, adr, at, t, mo, control_dependency) {}
463 virtual int Opcode() const;
464 virtual uint ideal_reg() const { return Op_RegN; }
465 virtual int store_Opcode() const { return Op_StoreN; }
466 virtual BasicType memory_type() const { return T_NARROWOOP; }
467 };
468
469 //------------------------------LoadKlassNode----------------------------------
470 // Load a Klass from an object
471 class LoadKlassNode : public LoadPNode {
472 protected:
473 // In most cases, LoadKlassNode does not have the control input set. If the control
474 // input is set, it must not be removed (by LoadNode::Ideal()).
475 virtual bool can_remove_control() const;
476 public:
477 LoadKlassNode(Node *c, Node *mem, Node *adr, const TypePtr *at, const TypeKlassPtr *tk, MemOrd mo)
478 : LoadPNode(c, mem, adr, at, tk, mo) {}
479 virtual int Opcode() const;
480 virtual const Type *Value( PhaseTransform *phase ) const;
481 virtual Node *Identity( PhaseTransform *phase );
482 virtual bool depends_only_on_test() const { return true; }
483
484 // Polymorphic factory method:
485 static Node* make(PhaseGVN& gvn, Node* ctl, Node* mem, Node* adr, const TypePtr* at,
486 const TypeKlassPtr* tk = TypeKlassPtr::OBJECT);
487 };
488
489 //------------------------------LoadNKlassNode---------------------------------
490 // Load a narrow Klass from an object.
491 class LoadNKlassNode : public LoadNNode {
492 public:
493 LoadNKlassNode(Node *c, Node *mem, Node *adr, const TypePtr *at, const TypeNarrowKlass *tk, MemOrd mo)
494 : LoadNNode(c, mem, adr, at, tk, mo) {}
495 virtual int Opcode() const;
496 virtual uint ideal_reg() const { return Op_RegN; }
497 virtual int store_Opcode() const { return Op_StoreNKlass; }
498 virtual BasicType memory_type() const { return T_NARROWKLASS; }
499
500 virtual const Type *Value( PhaseTransform *phase ) const;
501 virtual Node *Identity( PhaseTransform *phase );
502 virtual bool depends_only_on_test() const { return true; }
503 };
504
505
506 //------------------------------StoreNode--------------------------------------
507 // Store value; requires Store, Address and Value
508 class StoreNode : public MemNode {
509 private:
510 // On platforms with weak memory ordering (e.g., PPC, Ia64) we distinguish
511 // stores that can be reordered, and such requiring release semantics to
512 // adhere to the Java specification. The required behaviour is stored in
513 // this field.
514 const MemOrd _mo;
515 // Needed for proper cloning.
516 virtual uint size_of() const { return sizeof(*this); }
517 protected:
518 virtual uint cmp( const Node &n ) const;
519 virtual bool depends_only_on_test() const { return false; }
520
521 Node *Ideal_masked_input (PhaseGVN *phase, uint mask);
522 Node *Ideal_sign_extended_input(PhaseGVN *phase, int num_bits);
523
524 public:
525 // We must ensure that stores of object references will be visible
526 // only after the object's initialization. So the callers of this
527 // procedure must indicate that the store requires `release'
528 // semantics, if the stored value is an object reference that might
529 // point to a new object and may become externally visible.
530 StoreNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
531 : MemNode(c, mem, adr, at, val), _mo(mo) {
532 init_class_id(Class_Store);
533 }
534 StoreNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, Node *oop_store, MemOrd mo)
535 : MemNode(c, mem, adr, at, val, oop_store), _mo(mo) {
536 init_class_id(Class_Store);
537 }
538
539 inline bool is_unordered() const { return !is_release(); }
540 inline bool is_release() const {
541 assert((_mo == unordered || _mo == release), "unexpected");
542 return _mo == release;
543 }
544
545 // Conservatively release stores of object references in order to
546 // ensure visibility of object initialization.
547 static inline MemOrd release_if_reference(const BasicType t) {
548 #ifdef AARCH64
549 // AArch64 doesn't need a release store here because object
550 // initialization contains the necessary barriers.
551 return unordered;
552 #else
553 const MemOrd mo = (t == T_ARRAY ||
554 t == T_ADDRESS || // Might be the address of an object reference (`boxing').
555 t == T_OBJECT) ? release : unordered;
556 return mo;
557 #endif
558 }
559
560 // Polymorphic factory method
561 //
562 // We must ensure that stores of object references will be visible
563 // only after the object's initialization. So the callers of this
564 // procedure must indicate that the store requires `release'
565 // semantics, if the stored value is an object reference that might
566 // point to a new object and may become externally visible.
567 static StoreNode* make(PhaseGVN& gvn, Node *c, Node *mem, Node *adr,
568 const TypePtr* at, Node *val, BasicType bt, MemOrd mo);
569
570 virtual uint hash() const; // Check the type
571
572 // If the store is to Field memory and the pointer is non-null, we can
573 // zero out the control input.
574 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
575
576 // Compute a new Type for this node. Basically we just do the pre-check,
577 // then call the virtual add() to set the type.
578 virtual const Type *Value( PhaseTransform *phase ) const;
579
580 // Check for identity function on memory (Load then Store at same address)
581 virtual Node *Identity( PhaseTransform *phase );
582
583 // Do not match memory edge
584 virtual uint match_edge(uint idx) const;
585
586 virtual const Type *bottom_type() const; // returns Type::MEMORY
587
588 // Map a store opcode to its corresponding own opcode, trivially.
589 virtual int store_Opcode() const { return Opcode(); }
590
591 // have all possible loads of the value stored been optimized away?
592 bool value_never_loaded(PhaseTransform *phase) const;
593 };
594
595 //------------------------------StoreBNode-------------------------------------
596 // Store byte to memory
597 class StoreBNode : public StoreNode {
598 public:
599 StoreBNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
600 : StoreNode(c, mem, adr, at, val, mo) {}
601 virtual int Opcode() const;
602 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
603 virtual BasicType memory_type() const { return T_BYTE; }
604 };
605
606 //------------------------------StoreCNode-------------------------------------
607 // Store char/short to memory
608 class StoreCNode : public StoreNode {
609 public:
610 StoreCNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
611 : StoreNode(c, mem, adr, at, val, mo) {}
612 virtual int Opcode() const;
613 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
614 virtual BasicType memory_type() const { return T_CHAR; }
615 };
616
617 //------------------------------StoreINode-------------------------------------
618 // Store int to memory
619 class StoreINode : public StoreNode {
620 public:
621 StoreINode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
622 : StoreNode(c, mem, adr, at, val, mo) {}
623 virtual int Opcode() const;
624 virtual BasicType memory_type() const { return T_INT; }
625 };
626
627 //------------------------------StoreLNode-------------------------------------
628 // Store long to memory
629 class StoreLNode : public StoreNode {
630 virtual uint hash() const { return StoreNode::hash() + _require_atomic_access; }
631 virtual uint cmp( const Node &n ) const {
632 return _require_atomic_access == ((StoreLNode&)n)._require_atomic_access
633 && StoreNode::cmp(n);
634 }
635 virtual uint size_of() const { return sizeof(*this); }
636 const bool _require_atomic_access; // is piecewise store forbidden?
637
638 public:
639 StoreLNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo, bool require_atomic_access = false)
640 : StoreNode(c, mem, adr, at, val, mo), _require_atomic_access(require_atomic_access) {}
641 virtual int Opcode() const;
642 virtual BasicType memory_type() const { return T_LONG; }
643 bool require_atomic_access() const { return _require_atomic_access; }
644 static StoreLNode* make_atomic(Node* ctl, Node* mem, Node* adr, const TypePtr* adr_type, Node* val, MemOrd mo);
645 #ifndef PRODUCT
646 virtual void dump_spec(outputStream *st) const {
647 StoreNode::dump_spec(st);
648 if (_require_atomic_access) st->print(" Atomic!");
649 }
650 #endif
651 };
652
653 //------------------------------StoreFNode-------------------------------------
654 // Store float to memory
655 class StoreFNode : public StoreNode {
656 public:
657 StoreFNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
658 : StoreNode(c, mem, adr, at, val, mo) {}
659 virtual int Opcode() const;
660 virtual BasicType memory_type() const { return T_FLOAT; }
661 };
662
663 //------------------------------StoreDNode-------------------------------------
664 // Store double to memory
665 class StoreDNode : public StoreNode {
666 virtual uint hash() const { return StoreNode::hash() + _require_atomic_access; }
667 virtual uint cmp( const Node &n ) const {
668 return _require_atomic_access == ((StoreDNode&)n)._require_atomic_access
669 && StoreNode::cmp(n);
670 }
671 virtual uint size_of() const { return sizeof(*this); }
672 const bool _require_atomic_access; // is piecewise store forbidden?
673 public:
674 StoreDNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val,
675 MemOrd mo, bool require_atomic_access = false)
676 : StoreNode(c, mem, adr, at, val, mo), _require_atomic_access(require_atomic_access) {}
677 virtual int Opcode() const;
678 virtual BasicType memory_type() const { return T_DOUBLE; }
679 bool require_atomic_access() const { return _require_atomic_access; }
680 static StoreDNode* make_atomic(Node* ctl, Node* mem, Node* adr, const TypePtr* adr_type, Node* val, MemOrd mo);
681 #ifndef PRODUCT
682 virtual void dump_spec(outputStream *st) const {
683 StoreNode::dump_spec(st);
684 if (_require_atomic_access) st->print(" Atomic!");
685 }
686 #endif
687
688 };
689
690 //------------------------------StorePNode-------------------------------------
691 // Store pointer to memory
692 class StorePNode : public StoreNode {
693 public:
694 StorePNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
695 : StoreNode(c, mem, adr, at, val, mo) {}
696 virtual int Opcode() const;
697 virtual BasicType memory_type() const { return T_ADDRESS; }
698 };
699
700 //------------------------------StoreNNode-------------------------------------
701 // Store narrow oop to memory
702 class StoreNNode : public StoreNode {
703 public:
704 StoreNNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
705 : StoreNode(c, mem, adr, at, val, mo) {}
706 virtual int Opcode() const;
707 virtual BasicType memory_type() const { return T_NARROWOOP; }
708 };
709
710 //------------------------------StoreNKlassNode--------------------------------------
711 // Store narrow klass to memory
712 class StoreNKlassNode : public StoreNNode {
713 public:
714 StoreNKlassNode(Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, MemOrd mo)
715 : StoreNNode(c, mem, adr, at, val, mo) {}
716 virtual int Opcode() const;
717 virtual BasicType memory_type() const { return T_NARROWKLASS; }
718 };
719
720 //------------------------------StoreCMNode-----------------------------------
721 // Store card-mark byte to memory for CM
722 // The last StoreCM before a SafePoint must be preserved and occur after its "oop" store
723 // Preceeding equivalent StoreCMs may be eliminated.
724 class StoreCMNode : public StoreNode {
725 private:
726 virtual uint hash() const { return StoreNode::hash() + _oop_alias_idx; }
727 virtual uint cmp( const Node &n ) const {
728 return _oop_alias_idx == ((StoreCMNode&)n)._oop_alias_idx
729 && StoreNode::cmp(n);
730 }
731 virtual uint size_of() const { return sizeof(*this); }
732 int _oop_alias_idx; // The alias_idx of OopStore
733
734 public:
735 StoreCMNode( Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, Node *oop_store, int oop_alias_idx ) :
736 StoreNode(c, mem, adr, at, val, oop_store, MemNode::release),
737 _oop_alias_idx(oop_alias_idx) {
738 assert(_oop_alias_idx >= Compile::AliasIdxRaw ||
739 _oop_alias_idx == Compile::AliasIdxBot && Compile::current()->AliasLevel() == 0,
740 "bad oop alias idx");
741 }
742 virtual int Opcode() const;
743 virtual Node *Identity( PhaseTransform *phase );
744 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
745 virtual const Type *Value( PhaseTransform *phase ) const;
746 virtual BasicType memory_type() const { return T_VOID; } // unspecific
747 int oop_alias_idx() const { return _oop_alias_idx; }
748 };
749
750 //------------------------------LoadPLockedNode---------------------------------
751 // Load-locked a pointer from memory (either object or array).
752 // On Sparc & Intel this is implemented as a normal pointer load.
753 // On PowerPC and friends it's a real load-locked.
754 class LoadPLockedNode : public LoadPNode {
755 public:
756 LoadPLockedNode(Node *c, Node *mem, Node *adr, MemOrd mo)
757 : LoadPNode(c, mem, adr, TypeRawPtr::BOTTOM, TypeRawPtr::BOTTOM, mo) {}
758 virtual int Opcode() const;
759 virtual int store_Opcode() const { return Op_StorePConditional; }
760 virtual bool depends_only_on_test() const { return true; }
761 };
762
763 //------------------------------SCMemProjNode---------------------------------------
764 // This class defines a projection of the memory state of a store conditional node.
765 // These nodes return a value, but also update memory.
766 class SCMemProjNode : public ProjNode {
767 public:
768 enum {SCMEMPROJCON = (uint)-2};
769 SCMemProjNode( Node *src) : ProjNode( src, SCMEMPROJCON) { }
770 virtual int Opcode() const;
771 virtual bool is_CFG() const { return false; }
772 virtual const Type *bottom_type() const {return Type::MEMORY;}
773 virtual const TypePtr *adr_type() const {
774 Node* ctrl = in(0);
775 if (ctrl == NULL) return NULL; // node is dead
776 return ctrl->in(MemNode::Memory)->adr_type();
777 }
778 virtual uint ideal_reg() const { return 0;} // memory projections don't have a register
779 virtual const Type *Value( PhaseTransform *phase ) const;
780 #ifndef PRODUCT
781 virtual void dump_spec(outputStream *st) const {};
782 #endif
783 };
784
785 //------------------------------LoadStoreNode---------------------------
786 // Note: is_Mem() method returns 'true' for this class.
787 class LoadStoreNode : public Node {
788 private:
789 const Type* const _type; // What kind of value is loaded?
790 const TypePtr* _adr_type; // What kind of memory is being addressed?
791 virtual uint size_of() const; // Size is bigger
792 public:
793 LoadStoreNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at, const Type* rt, uint required );
794 virtual bool depends_only_on_test() const { return false; }
795 virtual uint match_edge(uint idx) const { return idx == MemNode::Address || idx == MemNode::ValueIn; }
796
797 virtual const Type *bottom_type() const { return _type; }
798 virtual uint ideal_reg() const;
799 virtual const class TypePtr *adr_type() const { return _adr_type; } // returns bottom_type of address
800
801 bool result_not_used() const;
802 };
803
804 class LoadStoreConditionalNode : public LoadStoreNode {
805 public:
806 enum {
807 ExpectedIn = MemNode::ValueIn+1 // One more input than MemNode
808 };
809 LoadStoreConditionalNode(Node *c, Node *mem, Node *adr, Node *val, Node *ex);
810 };
811
812 //------------------------------StorePConditionalNode---------------------------
813 // Conditionally store pointer to memory, if no change since prior
814 // load-locked. Sets flags for success or failure of the store.
815 class StorePConditionalNode : public LoadStoreConditionalNode {
816 public:
817 StorePConditionalNode( Node *c, Node *mem, Node *adr, Node *val, Node *ll ) : LoadStoreConditionalNode(c, mem, adr, val, ll) { }
818 virtual int Opcode() const;
819 // Produces flags
820 virtual uint ideal_reg() const { return Op_RegFlags; }
821 };
822
823 //------------------------------StoreIConditionalNode---------------------------
824 // Conditionally store int to memory, if no change since prior
825 // load-locked. Sets flags for success or failure of the store.
826 class StoreIConditionalNode : public LoadStoreConditionalNode {
827 public:
828 StoreIConditionalNode( Node *c, Node *mem, Node *adr, Node *val, Node *ii ) : LoadStoreConditionalNode(c, mem, adr, val, ii) { }
829 virtual int Opcode() const;
830 // Produces flags
831 virtual uint ideal_reg() const { return Op_RegFlags; }
832 };
833
834 //------------------------------StoreLConditionalNode---------------------------
835 // Conditionally store long to memory, if no change since prior
836 // load-locked. Sets flags for success or failure of the store.
837 class StoreLConditionalNode : public LoadStoreConditionalNode {
838 public:
839 StoreLConditionalNode( Node *c, Node *mem, Node *adr, Node *val, Node *ll ) : LoadStoreConditionalNode(c, mem, adr, val, ll) { }
840 virtual int Opcode() const;
841 // Produces flags
842 virtual uint ideal_reg() const { return Op_RegFlags; }
843 };
844
845
846 //------------------------------CompareAndSwapLNode---------------------------
847 class CompareAndSwapLNode : public LoadStoreConditionalNode {
848 public:
849 CompareAndSwapLNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex) : LoadStoreConditionalNode(c, mem, adr, val, ex) { }
850 virtual int Opcode() const;
851 };
852
853
854 //------------------------------CompareAndSwapINode---------------------------
855 class CompareAndSwapINode : public LoadStoreConditionalNode {
856 public:
857 CompareAndSwapINode( Node *c, Node *mem, Node *adr, Node *val, Node *ex) : LoadStoreConditionalNode(c, mem, adr, val, ex) { }
858 virtual int Opcode() const;
859 };
860
861
862 //------------------------------CompareAndSwapPNode---------------------------
863 class CompareAndSwapPNode : public LoadStoreConditionalNode {
864 public:
865 CompareAndSwapPNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex) : LoadStoreConditionalNode(c, mem, adr, val, ex) { }
866 virtual int Opcode() const;
867 };
868
869 //------------------------------CompareAndSwapNNode---------------------------
870 class CompareAndSwapNNode : public LoadStoreConditionalNode {
871 public:
872 CompareAndSwapNNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex) : LoadStoreConditionalNode(c, mem, adr, val, ex) { }
873 virtual int Opcode() const;
874 };
875
876 //------------------------------GetAndAddINode---------------------------
877 class GetAndAddINode : public LoadStoreNode {
878 public:
879 GetAndAddINode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeInt::INT, 4) { }
880 virtual int Opcode() const;
881 };
882
883 //------------------------------GetAndAddLNode---------------------------
884 class GetAndAddLNode : public LoadStoreNode {
885 public:
886 GetAndAddLNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeLong::LONG, 4) { }
887 virtual int Opcode() const;
888 };
889
890
891 //------------------------------GetAndSetINode---------------------------
892 class GetAndSetINode : public LoadStoreNode {
893 public:
894 GetAndSetINode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeInt::INT, 4) { }
895 virtual int Opcode() const;
896 };
897
898 //------------------------------GetAndSetINode---------------------------
899 class GetAndSetLNode : public LoadStoreNode {
900 public:
901 GetAndSetLNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at ) : LoadStoreNode(c, mem, adr, val, at, TypeLong::LONG, 4) { }
902 virtual int Opcode() const;
903 };
904
905 //------------------------------GetAndSetPNode---------------------------
906 class GetAndSetPNode : public LoadStoreNode {
907 public:
908 GetAndSetPNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at, const Type* t ) : LoadStoreNode(c, mem, adr, val, at, t, 4) { }
909 virtual int Opcode() const;
910 };
911
912 //------------------------------GetAndSetNNode---------------------------
913 class GetAndSetNNode : public LoadStoreNode {
914 public:
915 GetAndSetNNode( Node *c, Node *mem, Node *adr, Node *val, const TypePtr* at, const Type* t ) : LoadStoreNode(c, mem, adr, val, at, t, 4) { }
916 virtual int Opcode() const;
917 };
918
919 //------------------------------ClearArray-------------------------------------
920 class ClearArrayNode: public Node {
921 public:
922 ClearArrayNode( Node *ctrl, Node *arymem, Node *word_cnt, Node *base )
923 : Node(ctrl,arymem,word_cnt,base) {
924 init_class_id(Class_ClearArray);
925 }
926 virtual int Opcode() const;
927 virtual const Type *bottom_type() const { return Type::MEMORY; }
928 // ClearArray modifies array elements, and so affects only the
929 // array memory addressed by the bottom_type of its base address.
930 virtual const class TypePtr *adr_type() const;
931 virtual Node *Identity( PhaseTransform *phase );
932 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
933 virtual uint match_edge(uint idx) const;
934
935 // Clear the given area of an object or array.
936 // The start offset must always be aligned mod BytesPerInt.
937 // The end offset must always be aligned mod BytesPerLong.
938 // Return the new memory.
939 static Node* clear_memory(Node* control, Node* mem, Node* dest,
940 intptr_t start_offset,
941 intptr_t end_offset,
942 PhaseGVN* phase);
943 static Node* clear_memory(Node* control, Node* mem, Node* dest,
944 intptr_t start_offset,
945 Node* end_offset,
946 PhaseGVN* phase);
947 static Node* clear_memory(Node* control, Node* mem, Node* dest,
948 Node* start_offset,
949 Node* end_offset,
950 PhaseGVN* phase);
951 // Return allocation input memory edge if it is different instance
952 // or itself if it is the one we are looking for.
953 static bool step_through(Node** np, uint instance_id, PhaseTransform* phase);
954 };
955
956 //------------------------------MemBar-----------------------------------------
957 // There are different flavors of Memory Barriers to match the Java Memory
958 // Model. Monitor-enter and volatile-load act as Aquires: no following ref
959 // can be moved to before them. We insert a MemBar-Acquire after a FastLock or
960 // volatile-load. Monitor-exit and volatile-store act as Release: no
961 // preceding ref can be moved to after them. We insert a MemBar-Release
962 // before a FastUnlock or volatile-store. All volatiles need to be
963 // serialized, so we follow all volatile-stores with a MemBar-Volatile to
964 // separate it from any following volatile-load.
965 class MemBarNode: public MultiNode {
966 virtual uint hash() const ; // { return NO_HASH; }
967 virtual uint cmp( const Node &n ) const ; // Always fail, except on self
968
969 virtual uint size_of() const { return sizeof(*this); }
970 // Memory type this node is serializing. Usually either rawptr or bottom.
971 const TypePtr* _adr_type;
972
973 public:
974 enum {
975 Precedent = TypeFunc::Parms // optional edge to force precedence
976 };
977 MemBarNode(Compile* C, int alias_idx, Node* precedent);
978 virtual int Opcode() const = 0;
979 virtual const class TypePtr *adr_type() const { return _adr_type; }
980 virtual const Type *Value( PhaseTransform *phase ) const;
981 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
982 virtual uint match_edge(uint idx) const { return 0; }
983 virtual const Type *bottom_type() const { return TypeTuple::MEMBAR; }
984 virtual Node *match( const ProjNode *proj, const Matcher *m );
985 // Factory method. Builds a wide or narrow membar.
986 // Optional 'precedent' becomes an extra edge if not null.
987 static MemBarNode* make(Compile* C, int opcode,
988 int alias_idx = Compile::AliasIdxBot,
989 Node* precedent = NULL);
990 };
991
992 // "Acquire" - no following ref can move before (but earlier refs can
993 // follow, like an early Load stalled in cache). Requires multi-cpu
994 // visibility. Inserted after a volatile load.
995 class MemBarAcquireNode: public MemBarNode {
996 public:
997 MemBarAcquireNode(Compile* C, int alias_idx, Node* precedent)
998 : MemBarNode(C, alias_idx, precedent) {}
999 virtual int Opcode() const;
1000 };
1001
1002 // "Acquire" - no following ref can move before (but earlier refs can
1003 // follow, like an early Load stalled in cache). Requires multi-cpu
1004 // visibility. Inserted independ of any load, as required
1005 // for intrinsic sun.misc.Unsafe.loadFence().
1006 class LoadFenceNode: public MemBarNode {
1007 public:
1008 LoadFenceNode(Compile* C, int alias_idx, Node* precedent)
1009 : MemBarNode(C, alias_idx, precedent) {}
1010 virtual int Opcode() const;
1011 };
1012
1013 // "Release" - no earlier ref can move after (but later refs can move
1014 // up, like a speculative pipelined cache-hitting Load). Requires
1015 // multi-cpu visibility. Inserted before a volatile store.
1016 class MemBarReleaseNode: public MemBarNode {
1017 public:
1018 MemBarReleaseNode(Compile* C, int alias_idx, Node* precedent)
1019 : MemBarNode(C, alias_idx, precedent) {}
1020 virtual int Opcode() const;
1021 };
1022
1023 // "Release" - no earlier ref can move after (but later refs can move
1024 // up, like a speculative pipelined cache-hitting Load). Requires
1025 // multi-cpu visibility. Inserted independent of any store, as required
1026 // for intrinsic sun.misc.Unsafe.storeFence().
1027 class StoreFenceNode: public MemBarNode {
1028 public:
1029 StoreFenceNode(Compile* C, int alias_idx, Node* precedent)
1030 : MemBarNode(C, alias_idx, precedent) {}
1031 virtual int Opcode() const;
1032 };
1033
1034 // "Acquire" - no following ref can move before (but earlier refs can
1035 // follow, like an early Load stalled in cache). Requires multi-cpu
1036 // visibility. Inserted after a FastLock.
1037 class MemBarAcquireLockNode: public MemBarNode {
1038 public:
1039 MemBarAcquireLockNode(Compile* C, int alias_idx, Node* precedent)
1040 : MemBarNode(C, alias_idx, precedent) {}
1041 virtual int Opcode() const;
1042 };
1043
1044 // "Release" - no earlier ref can move after (but later refs can move
1045 // up, like a speculative pipelined cache-hitting Load). Requires
1046 // multi-cpu visibility. Inserted before a FastUnLock.
1047 class MemBarReleaseLockNode: public MemBarNode {
1048 public:
1049 MemBarReleaseLockNode(Compile* C, int alias_idx, Node* precedent)
1050 : MemBarNode(C, alias_idx, precedent) {}
1051 virtual int Opcode() const;
1052 };
1053
1054 class MemBarStoreStoreNode: public MemBarNode {
1055 public:
1056 MemBarStoreStoreNode(Compile* C, int alias_idx, Node* precedent)
1057 : MemBarNode(C, alias_idx, precedent) {
1058 init_class_id(Class_MemBarStoreStore);
1059 }
1060 virtual int Opcode() const;
1061 };
1062
1063 // Ordering between a volatile store and a following volatile load.
1064 // Requires multi-CPU visibility?
1065 class MemBarVolatileNode: public MemBarNode {
1066 public:
1067 MemBarVolatileNode(Compile* C, int alias_idx, Node* precedent)
1068 : MemBarNode(C, alias_idx, precedent) {}
1069 virtual int Opcode() const;
1070 };
1071
1072 // Ordering within the same CPU. Used to order unsafe memory references
1073 // inside the compiler when we lack alias info. Not needed "outside" the
1074 // compiler because the CPU does all the ordering for us.
1075 class MemBarCPUOrderNode: public MemBarNode {
1076 public:
1077 MemBarCPUOrderNode(Compile* C, int alias_idx, Node* precedent)
1078 : MemBarNode(C, alias_idx, precedent) {}
1079 virtual int Opcode() const;
1080 virtual uint ideal_reg() const { return 0; } // not matched in the AD file
1081 };
1082
1083 // Isolation of object setup after an AllocateNode and before next safepoint.
1084 // (See comment in memnode.cpp near InitializeNode::InitializeNode for semantics.)
1085 class InitializeNode: public MemBarNode {
1086 friend class AllocateNode;
1087
1088 enum {
1089 Incomplete = 0,
1090 Complete = 1,
1091 WithArraycopy = 2
1092 };
1093 int _is_complete;
1094
1095 bool _does_not_escape;
1096
1097 public:
1098 enum {
1099 Control = TypeFunc::Control,
1100 Memory = TypeFunc::Memory, // MergeMem for states affected by this op
1101 RawAddress = TypeFunc::Parms+0, // the newly-allocated raw address
1102 RawStores = TypeFunc::Parms+1 // zero or more stores (or TOP)
1103 };
1104
1105 InitializeNode(Compile* C, int adr_type, Node* rawoop);
1106 virtual int Opcode() const;
1107 virtual uint size_of() const { return sizeof(*this); }
1108 virtual uint ideal_reg() const { return 0; } // not matched in the AD file
1109 virtual const RegMask &in_RegMask(uint) const; // mask for RawAddress
1110
1111 // Manage incoming memory edges via a MergeMem on in(Memory):
1112 Node* memory(uint alias_idx);
1113
1114 // The raw memory edge coming directly from the Allocation.
1115 // The contents of this memory are *always* all-zero-bits.
1116 Node* zero_memory() { return memory(Compile::AliasIdxRaw); }
1117
1118 // Return the corresponding allocation for this initialization (or null if none).
1119 // (Note: Both InitializeNode::allocation and AllocateNode::initialization
1120 // are defined in graphKit.cpp, which sets up the bidirectional relation.)
1121 AllocateNode* allocation();
1122
1123 // Anything other than zeroing in this init?
1124 bool is_non_zero();
1125
1126 // An InitializeNode must completed before macro expansion is done.
1127 // Completion requires that the AllocateNode must be followed by
1128 // initialization of the new memory to zero, then to any initializers.
1129 bool is_complete() { return _is_complete != Incomplete; }
1130 bool is_complete_with_arraycopy() { return (_is_complete & WithArraycopy) != 0; }
1131
1132 // Mark complete. (Must not yet be complete.)
1133 void set_complete(PhaseGVN* phase);
1134 void set_complete_with_arraycopy() { _is_complete = Complete | WithArraycopy; }
1135
1136 bool does_not_escape() { return _does_not_escape; }
1137 void set_does_not_escape() { _does_not_escape = true; }
1138
1139 #ifdef ASSERT
1140 // ensure all non-degenerate stores are ordered and non-overlapping
1141 bool stores_are_sane(PhaseTransform* phase);
1142 #endif //ASSERT
1143
1144 // See if this store can be captured; return offset where it initializes.
1145 // Return 0 if the store cannot be moved (any sort of problem).
1146 intptr_t can_capture_store(StoreNode* st, PhaseTransform* phase, bool can_reshape);
1147
1148 // Capture another store; reformat it to write my internal raw memory.
1149 // Return the captured copy, else NULL if there is some sort of problem.
1150 Node* capture_store(StoreNode* st, intptr_t start, PhaseTransform* phase, bool can_reshape);
1151
1152 // Find captured store which corresponds to the range [start..start+size).
1153 // Return my own memory projection (meaning the initial zero bits)
1154 // if there is no such store. Return NULL if there is a problem.
1155 Node* find_captured_store(intptr_t start, int size_in_bytes, PhaseTransform* phase);
1156
1157 // Called when the associated AllocateNode is expanded into CFG.
1158 Node* complete_stores(Node* rawctl, Node* rawmem, Node* rawptr,
1159 intptr_t header_size, Node* size_in_bytes,
1160 PhaseGVN* phase);
1161
1162 private:
1163 void remove_extra_zeroes();
1164
1165 // Find out where a captured store should be placed (or already is placed).
1166 int captured_store_insertion_point(intptr_t start, int size_in_bytes,
1167 PhaseTransform* phase);
1168
1169 static intptr_t get_store_offset(Node* st, PhaseTransform* phase);
1170
1171 Node* make_raw_address(intptr_t offset, PhaseTransform* phase);
1172
1173 bool detect_init_independence(Node* n, int& count);
1174
1175 void coalesce_subword_stores(intptr_t header_size, Node* size_in_bytes,
1176 PhaseGVN* phase);
1177
1178 intptr_t find_next_fullword_store(uint i, PhaseGVN* phase);
1179 };
1180
1181 //------------------------------MergeMem---------------------------------------
1182 // (See comment in memnode.cpp near MergeMemNode::MergeMemNode for semantics.)
1183 class MergeMemNode: public Node {
1184 virtual uint hash() const ; // { return NO_HASH; }
1185 virtual uint cmp( const Node &n ) const ; // Always fail, except on self
1186 friend class MergeMemStream;
1187 MergeMemNode(Node* def); // clients use MergeMemNode::make
1188
1189 public:
1190 // If the input is a whole memory state, clone it with all its slices intact.
1191 // Otherwise, make a new memory state with just that base memory input.
1192 // In either case, the result is a newly created MergeMem.
1193 static MergeMemNode* make(Node* base_memory);
1194
1195 virtual int Opcode() const;
1196 virtual Node *Identity( PhaseTransform *phase );
1197 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
1198 virtual uint ideal_reg() const { return NotAMachineReg; }
1199 virtual uint match_edge(uint idx) const { return 0; }
1200 virtual const RegMask &out_RegMask() const;
1201 virtual const Type *bottom_type() const { return Type::MEMORY; }
1202 virtual const TypePtr *adr_type() const { return TypePtr::BOTTOM; }
1203 // sparse accessors
1204 // Fetch the previously stored "set_memory_at", or else the base memory.
1205 // (Caller should clone it if it is a phi-nest.)
1206 Node* memory_at(uint alias_idx) const;
1207 // set the memory, regardless of its previous value
1208 void set_memory_at(uint alias_idx, Node* n);
1209 // the "base" is the memory that provides the non-finite support
1210 Node* base_memory() const { return in(Compile::AliasIdxBot); }
1211 // warning: setting the base can implicitly set any of the other slices too
1212 void set_base_memory(Node* def);
1213 // sentinel value which denotes a copy of the base memory:
1214 Node* empty_memory() const { return in(Compile::AliasIdxTop); }
1215 static Node* make_empty_memory(); // where the sentinel comes from
1216 bool is_empty_memory(Node* n) const { assert((n == empty_memory()) == n->is_top(), "sanity"); return n->is_top(); }
1217 // hook for the iterator, to perform any necessary setup
1218 void iteration_setup(const MergeMemNode* other = NULL);
1219 // push sentinels until I am at least as long as the other (semantic no-op)
1220 void grow_to_match(const MergeMemNode* other);
1221 bool verify_sparse() const PRODUCT_RETURN0;
1222 #ifndef PRODUCT
1223 virtual void dump_spec(outputStream *st) const;
1224 #endif
1225 };
1226
1227 class MergeMemStream : public StackObj {
1228 private:
1229 MergeMemNode* _mm;
1230 const MergeMemNode* _mm2; // optional second guy, contributes non-empty iterations
1231 Node* _mm_base; // loop-invariant base memory of _mm
1232 int _idx;
1233 int _cnt;
1234 Node* _mem;
1235 Node* _mem2;
1236 int _cnt2;
1237
1238 void init(MergeMemNode* mm, const MergeMemNode* mm2 = NULL) {
1239 // subsume_node will break sparseness at times, whenever a memory slice
1240 // folds down to a copy of the base ("fat") memory. In such a case,
1241 // the raw edge will update to base, although it should be top.
1242 // This iterator will recognize either top or base_memory as an
1243 // "empty" slice. See is_empty, is_empty2, and next below.
1244 //
1245 // The sparseness property is repaired in MergeMemNode::Ideal.
1246 // As long as access to a MergeMem goes through this iterator
1247 // or the memory_at accessor, flaws in the sparseness will
1248 // never be observed.
1249 //
1250 // Also, iteration_setup repairs sparseness.
1251 assert(mm->verify_sparse(), "please, no dups of base");
1252 assert(mm2==NULL || mm2->verify_sparse(), "please, no dups of base");
1253
1254 _mm = mm;
1255 _mm_base = mm->base_memory();
1256 _mm2 = mm2;
1257 _cnt = mm->req();
1258 _idx = Compile::AliasIdxBot-1; // start at the base memory
1259 _mem = NULL;
1260 _mem2 = NULL;
1261 }
1262
1263 #ifdef ASSERT
1264 Node* check_memory() const {
1265 if (at_base_memory())
1266 return _mm->base_memory();
1267 else if ((uint)_idx < _mm->req() && !_mm->in(_idx)->is_top())
1268 return _mm->memory_at(_idx);
1269 else
1270 return _mm_base;
1271 }
1272 Node* check_memory2() const {
1273 return at_base_memory()? _mm2->base_memory(): _mm2->memory_at(_idx);
1274 }
1275 #endif
1276
1277 static bool match_memory(Node* mem, const MergeMemNode* mm, int idx) PRODUCT_RETURN0;
1278 void assert_synch() const {
1279 assert(!_mem || _idx >= _cnt || match_memory(_mem, _mm, _idx),
1280 "no side-effects except through the stream");
1281 }
1282
1283 public:
1284
1285 // expected usages:
1286 // for (MergeMemStream mms(mem->is_MergeMem()); next_non_empty(); ) { ... }
1287 // for (MergeMemStream mms(mem1, mem2); next_non_empty2(); ) { ... }
1288
1289 // iterate over one merge
1290 MergeMemStream(MergeMemNode* mm) {
1291 mm->iteration_setup();
1292 init(mm);
1293 debug_only(_cnt2 = 999);
1294 }
1295 // iterate in parallel over two merges
1296 // only iterates through non-empty elements of mm2
1297 MergeMemStream(MergeMemNode* mm, const MergeMemNode* mm2) {
1298 assert(mm2, "second argument must be a MergeMem also");
1299 ((MergeMemNode*)mm2)->iteration_setup(); // update hidden state
1300 mm->iteration_setup(mm2);
1301 init(mm, mm2);
1302 _cnt2 = mm2->req();
1303 }
1304 #ifdef ASSERT
1305 ~MergeMemStream() {
1306 assert_synch();
1307 }
1308 #endif
1309
1310 MergeMemNode* all_memory() const {
1311 return _mm;
1312 }
1313 Node* base_memory() const {
1314 assert(_mm_base == _mm->base_memory(), "no update to base memory, please");
1315 return _mm_base;
1316 }
1317 const MergeMemNode* all_memory2() const {
1318 assert(_mm2 != NULL, "");
1319 return _mm2;
1320 }
1321 bool at_base_memory() const {
1322 return _idx == Compile::AliasIdxBot;
1323 }
1324 int alias_idx() const {
1325 assert(_mem, "must call next 1st");
1326 return _idx;
1327 }
1328
1329 const TypePtr* adr_type() const {
1330 return Compile::current()->get_adr_type(alias_idx());
1331 }
1332
1333 const TypePtr* adr_type(Compile* C) const {
1334 return C->get_adr_type(alias_idx());
1335 }
1336 bool is_empty() const {
1337 assert(_mem, "must call next 1st");
1338 assert(_mem->is_top() == (_mem==_mm->empty_memory()), "correct sentinel");
1339 return _mem->is_top();
1340 }
1341 bool is_empty2() const {
1342 assert(_mem2, "must call next 1st");
1343 assert(_mem2->is_top() == (_mem2==_mm2->empty_memory()), "correct sentinel");
1344 return _mem2->is_top();
1345 }
1346 Node* memory() const {
1347 assert(!is_empty(), "must not be empty");
1348 assert_synch();
1349 return _mem;
1350 }
1351 // get the current memory, regardless of empty or non-empty status
1352 Node* force_memory() const {
1353 assert(!is_empty() || !at_base_memory(), "");
1354 // Use _mm_base to defend against updates to _mem->base_memory().
1355 Node *mem = _mem->is_top() ? _mm_base : _mem;
1356 assert(mem == check_memory(), "");
1357 return mem;
1358 }
1359 Node* memory2() const {
1360 assert(_mem2 == check_memory2(), "");
1361 return _mem2;
1362 }
1363 void set_memory(Node* mem) {
1364 if (at_base_memory()) {
1365 // Note that this does not change the invariant _mm_base.
1366 _mm->set_base_memory(mem);
1367 } else {
1368 _mm->set_memory_at(_idx, mem);
1369 }
1370 _mem = mem;
1371 assert_synch();
1372 }
1373
1374 // Recover from a side effect to the MergeMemNode.
1375 void set_memory() {
1376 _mem = _mm->in(_idx);
1377 }
1378
1379 bool next() { return next(false); }
1380 bool next2() { return next(true); }
1381
1382 bool next_non_empty() { return next_non_empty(false); }
1383 bool next_non_empty2() { return next_non_empty(true); }
1384 // next_non_empty2 can yield states where is_empty() is true
1385
1386 private:
1387 // find the next item, which might be empty
1388 bool next(bool have_mm2) {
1389 assert((_mm2 != NULL) == have_mm2, "use other next");
1390 assert_synch();
1391 if (++_idx < _cnt) {
1392 // Note: This iterator allows _mm to be non-sparse.
1393 // It behaves the same whether _mem is top or base_memory.
1394 _mem = _mm->in(_idx);
1395 if (have_mm2)
1396 _mem2 = _mm2->in((_idx < _cnt2) ? _idx : Compile::AliasIdxTop);
1397 return true;
1398 }
1399 return false;
1400 }
1401
1402 // find the next non-empty item
1403 bool next_non_empty(bool have_mm2) {
1404 while (next(have_mm2)) {
1405 if (!is_empty()) {
1406 // make sure _mem2 is filled in sensibly
1407 if (have_mm2 && _mem2->is_top()) _mem2 = _mm2->base_memory();
1408 return true;
1409 } else if (have_mm2 && !is_empty2()) {
1410 return true; // is_empty() == true
1411 }
1412 }
1413 return false;
1414 }
1415 };
1416
1417 //------------------------------Prefetch---------------------------------------
1418
1419 // Allocation prefetch which may fault, TLAB size have to be adjusted.
1420 class PrefetchAllocationNode : public Node {
1421 public:
1422 PrefetchAllocationNode(Node *mem, Node *adr) : Node(0,mem,adr) {}
1423 virtual int Opcode() const;
1424 virtual uint ideal_reg() const { return NotAMachineReg; }
1425 virtual uint match_edge(uint idx) const { return idx==2; }
1426 virtual const Type *bottom_type() const { return ( AllocatePrefetchStyle == 3 ) ? Type::MEMORY : Type::ABIO; }
1427 };
1428
1429 #endif // SHARE_VM_OPTO_MEMNODE_HPP