Fri, 25 May 2012 07:53:11 -0700
7170463: C2 should recognize "obj.getClass() == A.class" code pattern
Summary: optimize this code pattern obj.getClass() == A.class.
Reviewed-by: jrose, kvn
Contributed-by: Krystal Mok <sajia@taobao.com>
1 /*
2 * Copyright (c) 1997, 2011, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
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23 */
25 #ifndef SHARE_VM_OPTO_MEMNODE_HPP
26 #define SHARE_VM_OPTO_MEMNODE_HPP
28 #include "opto/multnode.hpp"
29 #include "opto/node.hpp"
30 #include "opto/opcodes.hpp"
31 #include "opto/type.hpp"
33 // Portions of code courtesy of Clifford Click
35 class MultiNode;
36 class PhaseCCP;
37 class PhaseTransform;
39 //------------------------------MemNode----------------------------------------
40 // Load or Store, possibly throwing a NULL pointer exception
41 class MemNode : public Node {
42 protected:
43 #ifdef ASSERT
44 const TypePtr* _adr_type; // What kind of memory is being addressed?
45 #endif
46 virtual uint size_of() const; // Size is bigger (ASSERT only)
47 public:
48 enum { Control, // When is it safe to do this load?
49 Memory, // Chunk of memory is being loaded from
50 Address, // Actually address, derived from base
51 ValueIn, // Value to store
52 OopStore // Preceeding oop store, only in StoreCM
53 };
54 protected:
55 MemNode( Node *c0, Node *c1, Node *c2, const TypePtr* at )
56 : Node(c0,c1,c2 ) {
57 init_class_id(Class_Mem);
58 debug_only(_adr_type=at; adr_type();)
59 }
60 MemNode( Node *c0, Node *c1, Node *c2, const TypePtr* at, Node *c3 )
61 : Node(c0,c1,c2,c3) {
62 init_class_id(Class_Mem);
63 debug_only(_adr_type=at; adr_type();)
64 }
65 MemNode( Node *c0, Node *c1, Node *c2, const TypePtr* at, Node *c3, Node *c4)
66 : Node(c0,c1,c2,c3,c4) {
67 init_class_id(Class_Mem);
68 debug_only(_adr_type=at; adr_type();)
69 }
71 public:
72 // Helpers for the optimizer. Documented in memnode.cpp.
73 static bool detect_ptr_independence(Node* p1, AllocateNode* a1,
74 Node* p2, AllocateNode* a2,
75 PhaseTransform* phase);
76 static bool adr_phi_is_loop_invariant(Node* adr_phi, Node* cast);
78 static Node *optimize_simple_memory_chain(Node *mchain, const TypePtr *t_adr, PhaseGVN *phase);
79 static Node *optimize_memory_chain(Node *mchain, const TypePtr *t_adr, PhaseGVN *phase);
80 // This one should probably be a phase-specific function:
81 static bool all_controls_dominate(Node* dom, Node* sub);
83 // Find any cast-away of null-ness and keep its control.
84 static Node *Ideal_common_DU_postCCP( PhaseCCP *ccp, Node* n, Node* adr );
85 virtual Node *Ideal_DU_postCCP( PhaseCCP *ccp );
87 virtual const class TypePtr *adr_type() const; // returns bottom_type of address
89 // Shared code for Ideal methods:
90 Node *Ideal_common(PhaseGVN *phase, bool can_reshape); // Return -1 for short-circuit NULL.
92 // Helper function for adr_type() implementations.
93 static const TypePtr* calculate_adr_type(const Type* t, const TypePtr* cross_check = NULL);
95 // Raw access function, to allow copying of adr_type efficiently in
96 // product builds and retain the debug info for debug builds.
97 const TypePtr *raw_adr_type() const {
98 #ifdef ASSERT
99 return _adr_type;
100 #else
101 return 0;
102 #endif
103 }
105 // Map a load or store opcode to its corresponding store opcode.
106 // (Return -1 if unknown.)
107 virtual int store_Opcode() const { return -1; }
109 // What is the type of the value in memory? (T_VOID mean "unspecified".)
110 virtual BasicType memory_type() const = 0;
111 virtual int memory_size() const {
112 #ifdef ASSERT
113 return type2aelembytes(memory_type(), true);
114 #else
115 return type2aelembytes(memory_type());
116 #endif
117 }
119 // Search through memory states which precede this node (load or store).
120 // Look for an exact match for the address, with no intervening
121 // aliased stores.
122 Node* find_previous_store(PhaseTransform* phase);
124 // Can this node (load or store) accurately see a stored value in
125 // the given memory state? (The state may or may not be in(Memory).)
126 Node* can_see_stored_value(Node* st, PhaseTransform* phase) const;
128 #ifndef PRODUCT
129 static void dump_adr_type(const Node* mem, const TypePtr* adr_type, outputStream *st);
130 virtual void dump_spec(outputStream *st) const;
131 #endif
132 };
134 //------------------------------LoadNode---------------------------------------
135 // Load value; requires Memory and Address
136 class LoadNode : public MemNode {
137 protected:
138 virtual uint cmp( const Node &n ) const;
139 virtual uint size_of() const; // Size is bigger
140 const Type* const _type; // What kind of value is loaded?
141 public:
143 LoadNode( Node *c, Node *mem, Node *adr, const TypePtr* at, const Type *rt )
144 : MemNode(c,mem,adr,at), _type(rt) {
145 init_class_id(Class_Load);
146 }
148 // Polymorphic factory method:
149 static Node* make( PhaseGVN& gvn, Node *c, Node *mem, Node *adr,
150 const TypePtr* at, const Type *rt, BasicType bt );
152 virtual uint hash() const; // Check the type
154 // Handle algebraic identities here. If we have an identity, return the Node
155 // we are equivalent to. We look for Load of a Store.
156 virtual Node *Identity( PhaseTransform *phase );
158 // If the load is from Field memory and the pointer is non-null, we can
159 // zero out the control input.
160 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
162 // Split instance field load through Phi.
163 Node* split_through_phi(PhaseGVN *phase);
165 // Recover original value from boxed values
166 Node *eliminate_autobox(PhaseGVN *phase);
168 // Compute a new Type for this node. Basically we just do the pre-check,
169 // then call the virtual add() to set the type.
170 virtual const Type *Value( PhaseTransform *phase ) const;
172 // Common methods for LoadKlass and LoadNKlass nodes.
173 const Type *klass_value_common( PhaseTransform *phase ) const;
174 Node *klass_identity_common( PhaseTransform *phase );
176 virtual uint ideal_reg() const;
177 virtual const Type *bottom_type() const;
178 // Following method is copied from TypeNode:
179 void set_type(const Type* t) {
180 assert(t != NULL, "sanity");
181 debug_only(uint check_hash = (VerifyHashTableKeys && _hash_lock) ? hash() : NO_HASH);
182 *(const Type**)&_type = t; // cast away const-ness
183 // If this node is in the hash table, make sure it doesn't need a rehash.
184 assert(check_hash == NO_HASH || check_hash == hash(), "type change must preserve hash code");
185 }
186 const Type* type() const { assert(_type != NULL, "sanity"); return _type; };
188 // Do not match memory edge
189 virtual uint match_edge(uint idx) const;
191 // Map a load opcode to its corresponding store opcode.
192 virtual int store_Opcode() const = 0;
194 // Check if the load's memory input is a Phi node with the same control.
195 bool is_instance_field_load_with_local_phi(Node* ctrl);
197 #ifndef PRODUCT
198 virtual void dump_spec(outputStream *st) const;
199 #endif
200 #ifdef ASSERT
201 // Helper function to allow a raw load without control edge for some cases
202 static bool is_immutable_value(Node* adr);
203 #endif
204 protected:
205 const Type* load_array_final_field(const TypeKlassPtr *tkls,
206 ciKlass* klass) const;
207 };
209 //------------------------------LoadBNode--------------------------------------
210 // Load a byte (8bits signed) from memory
211 class LoadBNode : public LoadNode {
212 public:
213 LoadBNode( Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeInt *ti = TypeInt::BYTE )
214 : LoadNode(c,mem,adr,at,ti) {}
215 virtual int Opcode() const;
216 virtual uint ideal_reg() const { return Op_RegI; }
217 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
218 virtual const Type *Value(PhaseTransform *phase) const;
219 virtual int store_Opcode() const { return Op_StoreB; }
220 virtual BasicType memory_type() const { return T_BYTE; }
221 };
223 //------------------------------LoadUBNode-------------------------------------
224 // Load a unsigned byte (8bits unsigned) from memory
225 class LoadUBNode : public LoadNode {
226 public:
227 LoadUBNode(Node* c, Node* mem, Node* adr, const TypePtr* at, const TypeInt* ti = TypeInt::UBYTE )
228 : LoadNode(c, mem, adr, at, ti) {}
229 virtual int Opcode() const;
230 virtual uint ideal_reg() const { return Op_RegI; }
231 virtual Node* Ideal(PhaseGVN *phase, bool can_reshape);
232 virtual const Type *Value(PhaseTransform *phase) const;
233 virtual int store_Opcode() const { return Op_StoreB; }
234 virtual BasicType memory_type() const { return T_BYTE; }
235 };
237 //------------------------------LoadUSNode-------------------------------------
238 // Load an unsigned short/char (16bits unsigned) from memory
239 class LoadUSNode : public LoadNode {
240 public:
241 LoadUSNode( Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeInt *ti = TypeInt::CHAR )
242 : LoadNode(c,mem,adr,at,ti) {}
243 virtual int Opcode() const;
244 virtual uint ideal_reg() const { return Op_RegI; }
245 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
246 virtual const Type *Value(PhaseTransform *phase) const;
247 virtual int store_Opcode() const { return Op_StoreC; }
248 virtual BasicType memory_type() const { return T_CHAR; }
249 };
251 //------------------------------LoadSNode--------------------------------------
252 // Load a short (16bits signed) from memory
253 class LoadSNode : public LoadNode {
254 public:
255 LoadSNode( Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeInt *ti = TypeInt::SHORT )
256 : LoadNode(c,mem,adr,at,ti) {}
257 virtual int Opcode() const;
258 virtual uint ideal_reg() const { return Op_RegI; }
259 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
260 virtual const Type *Value(PhaseTransform *phase) const;
261 virtual int store_Opcode() const { return Op_StoreC; }
262 virtual BasicType memory_type() const { return T_SHORT; }
263 };
265 //------------------------------LoadINode--------------------------------------
266 // Load an integer from memory
267 class LoadINode : public LoadNode {
268 public:
269 LoadINode( Node *c, Node *mem, Node *adr, const TypePtr* at, const TypeInt *ti = TypeInt::INT )
270 : LoadNode(c,mem,adr,at,ti) {}
271 virtual int Opcode() const;
272 virtual uint ideal_reg() const { return Op_RegI; }
273 virtual int store_Opcode() const { return Op_StoreI; }
274 virtual BasicType memory_type() const { return T_INT; }
275 };
277 //------------------------------LoadUI2LNode-----------------------------------
278 // Load an unsigned integer into long from memory
279 class LoadUI2LNode : public LoadNode {
280 public:
281 LoadUI2LNode(Node* c, Node* mem, Node* adr, const TypePtr* at, const TypeLong* t = TypeLong::UINT)
282 : LoadNode(c, mem, adr, at, t) {}
283 virtual int Opcode() const;
284 virtual uint ideal_reg() const { return Op_RegL; }
285 virtual int store_Opcode() const { return Op_StoreL; }
286 virtual BasicType memory_type() const { return T_LONG; }
287 };
289 //------------------------------LoadRangeNode----------------------------------
290 // Load an array length from the array
291 class LoadRangeNode : public LoadINode {
292 public:
293 LoadRangeNode( Node *c, Node *mem, Node *adr, const TypeInt *ti = TypeInt::POS )
294 : LoadINode(c,mem,adr,TypeAryPtr::RANGE,ti) {}
295 virtual int Opcode() const;
296 virtual const Type *Value( PhaseTransform *phase ) const;
297 virtual Node *Identity( PhaseTransform *phase );
298 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
299 };
301 //------------------------------LoadLNode--------------------------------------
302 // Load a long from memory
303 class LoadLNode : public LoadNode {
304 virtual uint hash() const { return LoadNode::hash() + _require_atomic_access; }
305 virtual uint cmp( const Node &n ) const {
306 return _require_atomic_access == ((LoadLNode&)n)._require_atomic_access
307 && LoadNode::cmp(n);
308 }
309 virtual uint size_of() const { return sizeof(*this); }
310 const bool _require_atomic_access; // is piecewise load forbidden?
312 public:
313 LoadLNode( Node *c, Node *mem, Node *adr, const TypePtr* at,
314 const TypeLong *tl = TypeLong::LONG,
315 bool require_atomic_access = false )
316 : LoadNode(c,mem,adr,at,tl)
317 , _require_atomic_access(require_atomic_access)
318 {}
319 virtual int Opcode() const;
320 virtual uint ideal_reg() const { return Op_RegL; }
321 virtual int store_Opcode() const { return Op_StoreL; }
322 virtual BasicType memory_type() const { return T_LONG; }
323 bool require_atomic_access() { return _require_atomic_access; }
324 static LoadLNode* make_atomic(Compile *C, Node* ctl, Node* mem, Node* adr, const TypePtr* adr_type, const Type* rt);
325 #ifndef PRODUCT
326 virtual void dump_spec(outputStream *st) const {
327 LoadNode::dump_spec(st);
328 if (_require_atomic_access) st->print(" Atomic!");
329 }
330 #endif
331 };
333 //------------------------------LoadL_unalignedNode----------------------------
334 // Load a long from unaligned memory
335 class LoadL_unalignedNode : public LoadLNode {
336 public:
337 LoadL_unalignedNode( Node *c, Node *mem, Node *adr, const TypePtr* at )
338 : LoadLNode(c,mem,adr,at) {}
339 virtual int Opcode() const;
340 };
342 //------------------------------LoadFNode--------------------------------------
343 // Load a float (64 bits) from memory
344 class LoadFNode : public LoadNode {
345 public:
346 LoadFNode( Node *c, Node *mem, Node *adr, const TypePtr* at, const Type *t = Type::FLOAT )
347 : LoadNode(c,mem,adr,at,t) {}
348 virtual int Opcode() const;
349 virtual uint ideal_reg() const { return Op_RegF; }
350 virtual int store_Opcode() const { return Op_StoreF; }
351 virtual BasicType memory_type() const { return T_FLOAT; }
352 };
354 //------------------------------LoadDNode--------------------------------------
355 // Load a double (64 bits) from memory
356 class LoadDNode : public LoadNode {
357 public:
358 LoadDNode( Node *c, Node *mem, Node *adr, const TypePtr* at, const Type *t = Type::DOUBLE )
359 : LoadNode(c,mem,adr,at,t) {}
360 virtual int Opcode() const;
361 virtual uint ideal_reg() const { return Op_RegD; }
362 virtual int store_Opcode() const { return Op_StoreD; }
363 virtual BasicType memory_type() const { return T_DOUBLE; }
364 };
366 //------------------------------LoadD_unalignedNode----------------------------
367 // Load a double from unaligned memory
368 class LoadD_unalignedNode : public LoadDNode {
369 public:
370 LoadD_unalignedNode( Node *c, Node *mem, Node *adr, const TypePtr* at )
371 : LoadDNode(c,mem,adr,at) {}
372 virtual int Opcode() const;
373 };
375 //------------------------------LoadPNode--------------------------------------
376 // Load a pointer from memory (either object or array)
377 class LoadPNode : public LoadNode {
378 public:
379 LoadPNode( Node *c, Node *mem, Node *adr, const TypePtr *at, const TypePtr* t )
380 : LoadNode(c,mem,adr,at,t) {}
381 virtual int Opcode() const;
382 virtual uint ideal_reg() const { return Op_RegP; }
383 virtual int store_Opcode() const { return Op_StoreP; }
384 virtual BasicType memory_type() const { return T_ADDRESS; }
385 // depends_only_on_test is almost always true, and needs to be almost always
386 // true to enable key hoisting & commoning optimizations. However, for the
387 // special case of RawPtr loads from TLS top & end, the control edge carries
388 // the dependence preventing hoisting past a Safepoint instead of the memory
389 // edge. (An unfortunate consequence of having Safepoints not set Raw
390 // Memory; itself an unfortunate consequence of having Nodes which produce
391 // results (new raw memory state) inside of loops preventing all manner of
392 // other optimizations). Basically, it's ugly but so is the alternative.
393 // See comment in macro.cpp, around line 125 expand_allocate_common().
394 virtual bool depends_only_on_test() const { return adr_type() != TypeRawPtr::BOTTOM; }
395 };
398 //------------------------------LoadNNode--------------------------------------
399 // Load a narrow oop from memory (either object or array)
400 class LoadNNode : public LoadNode {
401 public:
402 LoadNNode( Node *c, Node *mem, Node *adr, const TypePtr *at, const Type* t )
403 : LoadNode(c,mem,adr,at,t) {}
404 virtual int Opcode() const;
405 virtual uint ideal_reg() const { return Op_RegN; }
406 virtual int store_Opcode() const { return Op_StoreN; }
407 virtual BasicType memory_type() const { return T_NARROWOOP; }
408 // depends_only_on_test is almost always true, and needs to be almost always
409 // true to enable key hoisting & commoning optimizations. However, for the
410 // special case of RawPtr loads from TLS top & end, the control edge carries
411 // the dependence preventing hoisting past a Safepoint instead of the memory
412 // edge. (An unfortunate consequence of having Safepoints not set Raw
413 // Memory; itself an unfortunate consequence of having Nodes which produce
414 // results (new raw memory state) inside of loops preventing all manner of
415 // other optimizations). Basically, it's ugly but so is the alternative.
416 // See comment in macro.cpp, around line 125 expand_allocate_common().
417 virtual bool depends_only_on_test() const { return adr_type() != TypeRawPtr::BOTTOM; }
418 };
420 //------------------------------LoadKlassNode----------------------------------
421 // Load a Klass from an object
422 class LoadKlassNode : public LoadPNode {
423 public:
424 LoadKlassNode( Node *c, Node *mem, Node *adr, const TypePtr *at, const TypeKlassPtr *tk )
425 : LoadPNode(c,mem,adr,at,tk) {}
426 virtual int Opcode() const;
427 virtual const Type *Value( PhaseTransform *phase ) const;
428 virtual Node *Identity( PhaseTransform *phase );
429 virtual bool depends_only_on_test() const { return true; }
431 // Polymorphic factory method:
432 static Node* make( PhaseGVN& gvn, Node *mem, Node *adr, const TypePtr* at,
433 const TypeKlassPtr *tk = TypeKlassPtr::OBJECT );
434 };
436 //------------------------------LoadNKlassNode---------------------------------
437 // Load a narrow Klass from an object.
438 class LoadNKlassNode : public LoadNNode {
439 public:
440 LoadNKlassNode( Node *c, Node *mem, Node *adr, const TypePtr *at, const TypeNarrowOop *tk )
441 : LoadNNode(c,mem,adr,at,tk) {}
442 virtual int Opcode() const;
443 virtual uint ideal_reg() const { return Op_RegN; }
444 virtual int store_Opcode() const { return Op_StoreN; }
445 virtual BasicType memory_type() const { return T_NARROWOOP; }
447 virtual const Type *Value( PhaseTransform *phase ) const;
448 virtual Node *Identity( PhaseTransform *phase );
449 virtual bool depends_only_on_test() const { return true; }
450 };
453 //------------------------------StoreNode--------------------------------------
454 // Store value; requires Store, Address and Value
455 class StoreNode : public MemNode {
456 protected:
457 virtual uint cmp( const Node &n ) const;
458 virtual bool depends_only_on_test() const { return false; }
460 Node *Ideal_masked_input (PhaseGVN *phase, uint mask);
461 Node *Ideal_sign_extended_input(PhaseGVN *phase, int num_bits);
463 public:
464 StoreNode( Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val )
465 : MemNode(c,mem,adr,at,val) {
466 init_class_id(Class_Store);
467 }
468 StoreNode( Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, Node *oop_store )
469 : MemNode(c,mem,adr,at,val,oop_store) {
470 init_class_id(Class_Store);
471 }
473 // Polymorphic factory method:
474 static StoreNode* make( PhaseGVN& gvn, Node *c, Node *mem, Node *adr,
475 const TypePtr* at, Node *val, BasicType bt );
477 virtual uint hash() const; // Check the type
479 // If the store is to Field memory and the pointer is non-null, we can
480 // zero out the control input.
481 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
483 // Compute a new Type for this node. Basically we just do the pre-check,
484 // then call the virtual add() to set the type.
485 virtual const Type *Value( PhaseTransform *phase ) const;
487 // Check for identity function on memory (Load then Store at same address)
488 virtual Node *Identity( PhaseTransform *phase );
490 // Do not match memory edge
491 virtual uint match_edge(uint idx) const;
493 virtual const Type *bottom_type() const; // returns Type::MEMORY
495 // Map a store opcode to its corresponding own opcode, trivially.
496 virtual int store_Opcode() const { return Opcode(); }
498 // have all possible loads of the value stored been optimized away?
499 bool value_never_loaded(PhaseTransform *phase) const;
500 };
502 //------------------------------StoreBNode-------------------------------------
503 // Store byte to memory
504 class StoreBNode : public StoreNode {
505 public:
506 StoreBNode( Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val ) : StoreNode(c,mem,adr,at,val) {}
507 virtual int Opcode() const;
508 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
509 virtual BasicType memory_type() const { return T_BYTE; }
510 };
512 //------------------------------StoreCNode-------------------------------------
513 // Store char/short to memory
514 class StoreCNode : public StoreNode {
515 public:
516 StoreCNode( Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val ) : StoreNode(c,mem,adr,at,val) {}
517 virtual int Opcode() const;
518 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
519 virtual BasicType memory_type() const { return T_CHAR; }
520 };
522 //------------------------------StoreINode-------------------------------------
523 // Store int to memory
524 class StoreINode : public StoreNode {
525 public:
526 StoreINode( Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val ) : StoreNode(c,mem,adr,at,val) {}
527 virtual int Opcode() const;
528 virtual BasicType memory_type() const { return T_INT; }
529 };
531 //------------------------------StoreLNode-------------------------------------
532 // Store long to memory
533 class StoreLNode : public StoreNode {
534 virtual uint hash() const { return StoreNode::hash() + _require_atomic_access; }
535 virtual uint cmp( const Node &n ) const {
536 return _require_atomic_access == ((StoreLNode&)n)._require_atomic_access
537 && StoreNode::cmp(n);
538 }
539 virtual uint size_of() const { return sizeof(*this); }
540 const bool _require_atomic_access; // is piecewise store forbidden?
542 public:
543 StoreLNode( Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val,
544 bool require_atomic_access = false )
545 : StoreNode(c,mem,adr,at,val)
546 , _require_atomic_access(require_atomic_access)
547 {}
548 virtual int Opcode() const;
549 virtual BasicType memory_type() const { return T_LONG; }
550 bool require_atomic_access() { return _require_atomic_access; }
551 static StoreLNode* make_atomic(Compile *C, Node* ctl, Node* mem, Node* adr, const TypePtr* adr_type, Node* val);
552 #ifndef PRODUCT
553 virtual void dump_spec(outputStream *st) const {
554 StoreNode::dump_spec(st);
555 if (_require_atomic_access) st->print(" Atomic!");
556 }
557 #endif
558 };
560 //------------------------------StoreFNode-------------------------------------
561 // Store float to memory
562 class StoreFNode : public StoreNode {
563 public:
564 StoreFNode( Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val ) : StoreNode(c,mem,adr,at,val) {}
565 virtual int Opcode() const;
566 virtual BasicType memory_type() const { return T_FLOAT; }
567 };
569 //------------------------------StoreDNode-------------------------------------
570 // Store double to memory
571 class StoreDNode : public StoreNode {
572 public:
573 StoreDNode( Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val ) : StoreNode(c,mem,adr,at,val) {}
574 virtual int Opcode() const;
575 virtual BasicType memory_type() const { return T_DOUBLE; }
576 };
578 //------------------------------StorePNode-------------------------------------
579 // Store pointer to memory
580 class StorePNode : public StoreNode {
581 public:
582 StorePNode( Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val ) : StoreNode(c,mem,adr,at,val) {}
583 virtual int Opcode() const;
584 virtual BasicType memory_type() const { return T_ADDRESS; }
585 };
587 //------------------------------StoreNNode-------------------------------------
588 // Store narrow oop to memory
589 class StoreNNode : public StoreNode {
590 public:
591 StoreNNode( Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val ) : StoreNode(c,mem,adr,at,val) {}
592 virtual int Opcode() const;
593 virtual BasicType memory_type() const { return T_NARROWOOP; }
594 };
596 //------------------------------StoreCMNode-----------------------------------
597 // Store card-mark byte to memory for CM
598 // The last StoreCM before a SafePoint must be preserved and occur after its "oop" store
599 // Preceeding equivalent StoreCMs may be eliminated.
600 class StoreCMNode : public StoreNode {
601 private:
602 virtual uint hash() const { return StoreNode::hash() + _oop_alias_idx; }
603 virtual uint cmp( const Node &n ) const {
604 return _oop_alias_idx == ((StoreCMNode&)n)._oop_alias_idx
605 && StoreNode::cmp(n);
606 }
607 virtual uint size_of() const { return sizeof(*this); }
608 int _oop_alias_idx; // The alias_idx of OopStore
610 public:
611 StoreCMNode( Node *c, Node *mem, Node *adr, const TypePtr* at, Node *val, Node *oop_store, int oop_alias_idx ) :
612 StoreNode(c,mem,adr,at,val,oop_store),
613 _oop_alias_idx(oop_alias_idx) {
614 assert(_oop_alias_idx >= Compile::AliasIdxRaw ||
615 _oop_alias_idx == Compile::AliasIdxBot && Compile::current()->AliasLevel() == 0,
616 "bad oop alias idx");
617 }
618 virtual int Opcode() const;
619 virtual Node *Identity( PhaseTransform *phase );
620 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
621 virtual const Type *Value( PhaseTransform *phase ) const;
622 virtual BasicType memory_type() const { return T_VOID; } // unspecific
623 int oop_alias_idx() const { return _oop_alias_idx; }
624 };
626 //------------------------------LoadPLockedNode---------------------------------
627 // Load-locked a pointer from memory (either object or array).
628 // On Sparc & Intel this is implemented as a normal pointer load.
629 // On PowerPC and friends it's a real load-locked.
630 class LoadPLockedNode : public LoadPNode {
631 public:
632 LoadPLockedNode( Node *c, Node *mem, Node *adr )
633 : LoadPNode(c,mem,adr,TypeRawPtr::BOTTOM, TypeRawPtr::BOTTOM) {}
634 virtual int Opcode() const;
635 virtual int store_Opcode() const { return Op_StorePConditional; }
636 virtual bool depends_only_on_test() const { return true; }
637 };
639 //------------------------------LoadLLockedNode---------------------------------
640 // Load-locked a pointer from memory (either object or array).
641 // On Sparc & Intel this is implemented as a normal long load.
642 class LoadLLockedNode : public LoadLNode {
643 public:
644 LoadLLockedNode( Node *c, Node *mem, Node *adr )
645 : LoadLNode(c,mem,adr,TypeRawPtr::BOTTOM, TypeLong::LONG) {}
646 virtual int Opcode() const;
647 virtual int store_Opcode() const { return Op_StoreLConditional; }
648 };
650 //------------------------------SCMemProjNode---------------------------------------
651 // This class defines a projection of the memory state of a store conditional node.
652 // These nodes return a value, but also update memory.
653 class SCMemProjNode : public ProjNode {
654 public:
655 enum {SCMEMPROJCON = (uint)-2};
656 SCMemProjNode( Node *src) : ProjNode( src, SCMEMPROJCON) { }
657 virtual int Opcode() const;
658 virtual bool is_CFG() const { return false; }
659 virtual const Type *bottom_type() const {return Type::MEMORY;}
660 virtual const TypePtr *adr_type() const { return in(0)->in(MemNode::Memory)->adr_type();}
661 virtual uint ideal_reg() const { return 0;} // memory projections don't have a register
662 virtual const Type *Value( PhaseTransform *phase ) const;
663 #ifndef PRODUCT
664 virtual void dump_spec(outputStream *st) const {};
665 #endif
666 };
668 //------------------------------LoadStoreNode---------------------------
669 // Note: is_Mem() method returns 'true' for this class.
670 class LoadStoreNode : public Node {
671 public:
672 enum {
673 ExpectedIn = MemNode::ValueIn+1 // One more input than MemNode
674 };
675 LoadStoreNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex);
676 virtual bool depends_only_on_test() const { return false; }
677 virtual const Type *bottom_type() const { return TypeInt::BOOL; }
678 virtual uint ideal_reg() const { return Op_RegI; }
679 virtual uint match_edge(uint idx) const { return idx == MemNode::Address || idx == MemNode::ValueIn; }
680 };
682 //------------------------------StorePConditionalNode---------------------------
683 // Conditionally store pointer to memory, if no change since prior
684 // load-locked. Sets flags for success or failure of the store.
685 class StorePConditionalNode : public LoadStoreNode {
686 public:
687 StorePConditionalNode( Node *c, Node *mem, Node *adr, Node *val, Node *ll ) : LoadStoreNode(c, mem, adr, val, ll) { }
688 virtual int Opcode() const;
689 // Produces flags
690 virtual uint ideal_reg() const { return Op_RegFlags; }
691 };
693 //------------------------------StoreIConditionalNode---------------------------
694 // Conditionally store int to memory, if no change since prior
695 // load-locked. Sets flags for success or failure of the store.
696 class StoreIConditionalNode : public LoadStoreNode {
697 public:
698 StoreIConditionalNode( Node *c, Node *mem, Node *adr, Node *val, Node *ii ) : LoadStoreNode(c, mem, adr, val, ii) { }
699 virtual int Opcode() const;
700 // Produces flags
701 virtual uint ideal_reg() const { return Op_RegFlags; }
702 };
704 //------------------------------StoreLConditionalNode---------------------------
705 // Conditionally store long to memory, if no change since prior
706 // load-locked. Sets flags for success or failure of the store.
707 class StoreLConditionalNode : public LoadStoreNode {
708 public:
709 StoreLConditionalNode( Node *c, Node *mem, Node *adr, Node *val, Node *ll ) : LoadStoreNode(c, mem, adr, val, ll) { }
710 virtual int Opcode() const;
711 // Produces flags
712 virtual uint ideal_reg() const { return Op_RegFlags; }
713 };
716 //------------------------------CompareAndSwapLNode---------------------------
717 class CompareAndSwapLNode : public LoadStoreNode {
718 public:
719 CompareAndSwapLNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex) : LoadStoreNode(c, mem, adr, val, ex) { }
720 virtual int Opcode() const;
721 };
724 //------------------------------CompareAndSwapINode---------------------------
725 class CompareAndSwapINode : public LoadStoreNode {
726 public:
727 CompareAndSwapINode( Node *c, Node *mem, Node *adr, Node *val, Node *ex) : LoadStoreNode(c, mem, adr, val, ex) { }
728 virtual int Opcode() const;
729 };
732 //------------------------------CompareAndSwapPNode---------------------------
733 class CompareAndSwapPNode : public LoadStoreNode {
734 public:
735 CompareAndSwapPNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex) : LoadStoreNode(c, mem, adr, val, ex) { }
736 virtual int Opcode() const;
737 };
739 //------------------------------CompareAndSwapNNode---------------------------
740 class CompareAndSwapNNode : public LoadStoreNode {
741 public:
742 CompareAndSwapNNode( Node *c, Node *mem, Node *adr, Node *val, Node *ex) : LoadStoreNode(c, mem, adr, val, ex) { }
743 virtual int Opcode() const;
744 };
746 //------------------------------ClearArray-------------------------------------
747 class ClearArrayNode: public Node {
748 public:
749 ClearArrayNode( Node *ctrl, Node *arymem, Node *word_cnt, Node *base )
750 : Node(ctrl,arymem,word_cnt,base) {
751 init_class_id(Class_ClearArray);
752 }
753 virtual int Opcode() const;
754 virtual const Type *bottom_type() const { return Type::MEMORY; }
755 // ClearArray modifies array elements, and so affects only the
756 // array memory addressed by the bottom_type of its base address.
757 virtual const class TypePtr *adr_type() const;
758 virtual Node *Identity( PhaseTransform *phase );
759 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
760 virtual uint match_edge(uint idx) const;
762 // Clear the given area of an object or array.
763 // The start offset must always be aligned mod BytesPerInt.
764 // The end offset must always be aligned mod BytesPerLong.
765 // Return the new memory.
766 static Node* clear_memory(Node* control, Node* mem, Node* dest,
767 intptr_t start_offset,
768 intptr_t end_offset,
769 PhaseGVN* phase);
770 static Node* clear_memory(Node* control, Node* mem, Node* dest,
771 intptr_t start_offset,
772 Node* end_offset,
773 PhaseGVN* phase);
774 static Node* clear_memory(Node* control, Node* mem, Node* dest,
775 Node* start_offset,
776 Node* end_offset,
777 PhaseGVN* phase);
778 // Return allocation input memory edge if it is different instance
779 // or itself if it is the one we are looking for.
780 static bool step_through(Node** np, uint instance_id, PhaseTransform* phase);
781 };
783 //------------------------------StrIntrinsic-------------------------------
784 // Base class for Ideal nodes used in String instrinsic code.
785 class StrIntrinsicNode: public Node {
786 public:
787 StrIntrinsicNode(Node* control, Node* char_array_mem,
788 Node* s1, Node* c1, Node* s2, Node* c2):
789 Node(control, char_array_mem, s1, c1, s2, c2) {
790 }
792 StrIntrinsicNode(Node* control, Node* char_array_mem,
793 Node* s1, Node* s2, Node* c):
794 Node(control, char_array_mem, s1, s2, c) {
795 }
797 StrIntrinsicNode(Node* control, Node* char_array_mem,
798 Node* s1, Node* s2):
799 Node(control, char_array_mem, s1, s2) {
800 }
802 virtual bool depends_only_on_test() const { return false; }
803 virtual const TypePtr* adr_type() const { return TypeAryPtr::CHARS; }
804 virtual uint match_edge(uint idx) const;
805 virtual uint ideal_reg() const { return Op_RegI; }
806 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
807 virtual const Type *Value(PhaseTransform *phase) const;
808 };
810 //------------------------------StrComp-------------------------------------
811 class StrCompNode: public StrIntrinsicNode {
812 public:
813 StrCompNode(Node* control, Node* char_array_mem,
814 Node* s1, Node* c1, Node* s2, Node* c2):
815 StrIntrinsicNode(control, char_array_mem, s1, c1, s2, c2) {};
816 virtual int Opcode() const;
817 virtual const Type* bottom_type() const { return TypeInt::INT; }
818 };
820 //------------------------------StrEquals-------------------------------------
821 class StrEqualsNode: public StrIntrinsicNode {
822 public:
823 StrEqualsNode(Node* control, Node* char_array_mem,
824 Node* s1, Node* s2, Node* c):
825 StrIntrinsicNode(control, char_array_mem, s1, s2, c) {};
826 virtual int Opcode() const;
827 virtual const Type* bottom_type() const { return TypeInt::BOOL; }
828 };
830 //------------------------------StrIndexOf-------------------------------------
831 class StrIndexOfNode: public StrIntrinsicNode {
832 public:
833 StrIndexOfNode(Node* control, Node* char_array_mem,
834 Node* s1, Node* c1, Node* s2, Node* c2):
835 StrIntrinsicNode(control, char_array_mem, s1, c1, s2, c2) {};
836 virtual int Opcode() const;
837 virtual const Type* bottom_type() const { return TypeInt::INT; }
838 };
840 //------------------------------AryEq---------------------------------------
841 class AryEqNode: public StrIntrinsicNode {
842 public:
843 AryEqNode(Node* control, Node* char_array_mem, Node* s1, Node* s2):
844 StrIntrinsicNode(control, char_array_mem, s1, s2) {};
845 virtual int Opcode() const;
846 virtual const Type* bottom_type() const { return TypeInt::BOOL; }
847 };
849 //------------------------------MemBar-----------------------------------------
850 // There are different flavors of Memory Barriers to match the Java Memory
851 // Model. Monitor-enter and volatile-load act as Aquires: no following ref
852 // can be moved to before them. We insert a MemBar-Acquire after a FastLock or
853 // volatile-load. Monitor-exit and volatile-store act as Release: no
854 // preceding ref can be moved to after them. We insert a MemBar-Release
855 // before a FastUnlock or volatile-store. All volatiles need to be
856 // serialized, so we follow all volatile-stores with a MemBar-Volatile to
857 // separate it from any following volatile-load.
858 class MemBarNode: public MultiNode {
859 virtual uint hash() const ; // { return NO_HASH; }
860 virtual uint cmp( const Node &n ) const ; // Always fail, except on self
862 virtual uint size_of() const { return sizeof(*this); }
863 // Memory type this node is serializing. Usually either rawptr or bottom.
864 const TypePtr* _adr_type;
866 public:
867 enum {
868 Precedent = TypeFunc::Parms // optional edge to force precedence
869 };
870 MemBarNode(Compile* C, int alias_idx, Node* precedent);
871 virtual int Opcode() const = 0;
872 virtual const class TypePtr *adr_type() const { return _adr_type; }
873 virtual const Type *Value( PhaseTransform *phase ) const;
874 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
875 virtual uint match_edge(uint idx) const { return 0; }
876 virtual const Type *bottom_type() const { return TypeTuple::MEMBAR; }
877 virtual Node *match( const ProjNode *proj, const Matcher *m );
878 // Factory method. Builds a wide or narrow membar.
879 // Optional 'precedent' becomes an extra edge if not null.
880 static MemBarNode* make(Compile* C, int opcode,
881 int alias_idx = Compile::AliasIdxBot,
882 Node* precedent = NULL);
883 };
885 // "Acquire" - no following ref can move before (but earlier refs can
886 // follow, like an early Load stalled in cache). Requires multi-cpu
887 // visibility. Inserted after a volatile load.
888 class MemBarAcquireNode: public MemBarNode {
889 public:
890 MemBarAcquireNode(Compile* C, int alias_idx, Node* precedent)
891 : MemBarNode(C, alias_idx, precedent) {}
892 virtual int Opcode() const;
893 };
895 // "Release" - no earlier ref can move after (but later refs can move
896 // up, like a speculative pipelined cache-hitting Load). Requires
897 // multi-cpu visibility. Inserted before a volatile store.
898 class MemBarReleaseNode: public MemBarNode {
899 public:
900 MemBarReleaseNode(Compile* C, int alias_idx, Node* precedent)
901 : MemBarNode(C, alias_idx, precedent) {}
902 virtual int Opcode() const;
903 };
905 // "Acquire" - no following ref can move before (but earlier refs can
906 // follow, like an early Load stalled in cache). Requires multi-cpu
907 // visibility. Inserted after a FastLock.
908 class MemBarAcquireLockNode: public MemBarNode {
909 public:
910 MemBarAcquireLockNode(Compile* C, int alias_idx, Node* precedent)
911 : MemBarNode(C, alias_idx, precedent) {}
912 virtual int Opcode() const;
913 };
915 // "Release" - no earlier ref can move after (but later refs can move
916 // up, like a speculative pipelined cache-hitting Load). Requires
917 // multi-cpu visibility. Inserted before a FastUnLock.
918 class MemBarReleaseLockNode: public MemBarNode {
919 public:
920 MemBarReleaseLockNode(Compile* C, int alias_idx, Node* precedent)
921 : MemBarNode(C, alias_idx, precedent) {}
922 virtual int Opcode() const;
923 };
925 class MemBarStoreStoreNode: public MemBarNode {
926 public:
927 MemBarStoreStoreNode(Compile* C, int alias_idx, Node* precedent)
928 : MemBarNode(C, alias_idx, precedent) {
929 init_class_id(Class_MemBarStoreStore);
930 }
931 virtual int Opcode() const;
932 };
934 // Ordering between a volatile store and a following volatile load.
935 // Requires multi-CPU visibility?
936 class MemBarVolatileNode: public MemBarNode {
937 public:
938 MemBarVolatileNode(Compile* C, int alias_idx, Node* precedent)
939 : MemBarNode(C, alias_idx, precedent) {}
940 virtual int Opcode() const;
941 };
943 // Ordering within the same CPU. Used to order unsafe memory references
944 // inside the compiler when we lack alias info. Not needed "outside" the
945 // compiler because the CPU does all the ordering for us.
946 class MemBarCPUOrderNode: public MemBarNode {
947 public:
948 MemBarCPUOrderNode(Compile* C, int alias_idx, Node* precedent)
949 : MemBarNode(C, alias_idx, precedent) {}
950 virtual int Opcode() const;
951 virtual uint ideal_reg() const { return 0; } // not matched in the AD file
952 };
954 // Isolation of object setup after an AllocateNode and before next safepoint.
955 // (See comment in memnode.cpp near InitializeNode::InitializeNode for semantics.)
956 class InitializeNode: public MemBarNode {
957 friend class AllocateNode;
959 enum {
960 Incomplete = 0,
961 Complete = 1,
962 WithArraycopy = 2
963 };
964 int _is_complete;
966 bool _does_not_escape;
968 public:
969 enum {
970 Control = TypeFunc::Control,
971 Memory = TypeFunc::Memory, // MergeMem for states affected by this op
972 RawAddress = TypeFunc::Parms+0, // the newly-allocated raw address
973 RawStores = TypeFunc::Parms+1 // zero or more stores (or TOP)
974 };
976 InitializeNode(Compile* C, int adr_type, Node* rawoop);
977 virtual int Opcode() const;
978 virtual uint size_of() const { return sizeof(*this); }
979 virtual uint ideal_reg() const { return 0; } // not matched in the AD file
980 virtual const RegMask &in_RegMask(uint) const; // mask for RawAddress
982 // Manage incoming memory edges via a MergeMem on in(Memory):
983 Node* memory(uint alias_idx);
985 // The raw memory edge coming directly from the Allocation.
986 // The contents of this memory are *always* all-zero-bits.
987 Node* zero_memory() { return memory(Compile::AliasIdxRaw); }
989 // Return the corresponding allocation for this initialization (or null if none).
990 // (Note: Both InitializeNode::allocation and AllocateNode::initialization
991 // are defined in graphKit.cpp, which sets up the bidirectional relation.)
992 AllocateNode* allocation();
994 // Anything other than zeroing in this init?
995 bool is_non_zero();
997 // An InitializeNode must completed before macro expansion is done.
998 // Completion requires that the AllocateNode must be followed by
999 // initialization of the new memory to zero, then to any initializers.
1000 bool is_complete() { return _is_complete != Incomplete; }
1001 bool is_complete_with_arraycopy() { return (_is_complete & WithArraycopy) != 0; }
1003 // Mark complete. (Must not yet be complete.)
1004 void set_complete(PhaseGVN* phase);
1005 void set_complete_with_arraycopy() { _is_complete = Complete | WithArraycopy; }
1007 bool does_not_escape() { return _does_not_escape; }
1008 void set_does_not_escape() { _does_not_escape = true; }
1010 #ifdef ASSERT
1011 // ensure all non-degenerate stores are ordered and non-overlapping
1012 bool stores_are_sane(PhaseTransform* phase);
1013 #endif //ASSERT
1015 // See if this store can be captured; return offset where it initializes.
1016 // Return 0 if the store cannot be moved (any sort of problem).
1017 intptr_t can_capture_store(StoreNode* st, PhaseTransform* phase);
1019 // Capture another store; reformat it to write my internal raw memory.
1020 // Return the captured copy, else NULL if there is some sort of problem.
1021 Node* capture_store(StoreNode* st, intptr_t start, PhaseTransform* phase);
1023 // Find captured store which corresponds to the range [start..start+size).
1024 // Return my own memory projection (meaning the initial zero bits)
1025 // if there is no such store. Return NULL if there is a problem.
1026 Node* find_captured_store(intptr_t start, int size_in_bytes, PhaseTransform* phase);
1028 // Called when the associated AllocateNode is expanded into CFG.
1029 Node* complete_stores(Node* rawctl, Node* rawmem, Node* rawptr,
1030 intptr_t header_size, Node* size_in_bytes,
1031 PhaseGVN* phase);
1033 private:
1034 void remove_extra_zeroes();
1036 // Find out where a captured store should be placed (or already is placed).
1037 int captured_store_insertion_point(intptr_t start, int size_in_bytes,
1038 PhaseTransform* phase);
1040 static intptr_t get_store_offset(Node* st, PhaseTransform* phase);
1042 Node* make_raw_address(intptr_t offset, PhaseTransform* phase);
1044 bool detect_init_independence(Node* n, bool st_is_pinned, int& count);
1046 void coalesce_subword_stores(intptr_t header_size, Node* size_in_bytes,
1047 PhaseGVN* phase);
1049 intptr_t find_next_fullword_store(uint i, PhaseGVN* phase);
1050 };
1052 //------------------------------MergeMem---------------------------------------
1053 // (See comment in memnode.cpp near MergeMemNode::MergeMemNode for semantics.)
1054 class MergeMemNode: public Node {
1055 virtual uint hash() const ; // { return NO_HASH; }
1056 virtual uint cmp( const Node &n ) const ; // Always fail, except on self
1057 friend class MergeMemStream;
1058 MergeMemNode(Node* def); // clients use MergeMemNode::make
1060 public:
1061 // If the input is a whole memory state, clone it with all its slices intact.
1062 // Otherwise, make a new memory state with just that base memory input.
1063 // In either case, the result is a newly created MergeMem.
1064 static MergeMemNode* make(Compile* C, Node* base_memory);
1066 virtual int Opcode() const;
1067 virtual Node *Identity( PhaseTransform *phase );
1068 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
1069 virtual uint ideal_reg() const { return NotAMachineReg; }
1070 virtual uint match_edge(uint idx) const { return 0; }
1071 virtual const RegMask &out_RegMask() const;
1072 virtual const Type *bottom_type() const { return Type::MEMORY; }
1073 virtual const TypePtr *adr_type() const { return TypePtr::BOTTOM; }
1074 // sparse accessors
1075 // Fetch the previously stored "set_memory_at", or else the base memory.
1076 // (Caller should clone it if it is a phi-nest.)
1077 Node* memory_at(uint alias_idx) const;
1078 // set the memory, regardless of its previous value
1079 void set_memory_at(uint alias_idx, Node* n);
1080 // the "base" is the memory that provides the non-finite support
1081 Node* base_memory() const { return in(Compile::AliasIdxBot); }
1082 // warning: setting the base can implicitly set any of the other slices too
1083 void set_base_memory(Node* def);
1084 // sentinel value which denotes a copy of the base memory:
1085 Node* empty_memory() const { return in(Compile::AliasIdxTop); }
1086 static Node* make_empty_memory(); // where the sentinel comes from
1087 bool is_empty_memory(Node* n) const { assert((n == empty_memory()) == n->is_top(), "sanity"); return n->is_top(); }
1088 // hook for the iterator, to perform any necessary setup
1089 void iteration_setup(const MergeMemNode* other = NULL);
1090 // push sentinels until I am at least as long as the other (semantic no-op)
1091 void grow_to_match(const MergeMemNode* other);
1092 bool verify_sparse() const PRODUCT_RETURN0;
1093 #ifndef PRODUCT
1094 virtual void dump_spec(outputStream *st) const;
1095 #endif
1096 };
1098 class MergeMemStream : public StackObj {
1099 private:
1100 MergeMemNode* _mm;
1101 const MergeMemNode* _mm2; // optional second guy, contributes non-empty iterations
1102 Node* _mm_base; // loop-invariant base memory of _mm
1103 int _idx;
1104 int _cnt;
1105 Node* _mem;
1106 Node* _mem2;
1107 int _cnt2;
1109 void init(MergeMemNode* mm, const MergeMemNode* mm2 = NULL) {
1110 // subsume_node will break sparseness at times, whenever a memory slice
1111 // folds down to a copy of the base ("fat") memory. In such a case,
1112 // the raw edge will update to base, although it should be top.
1113 // This iterator will recognize either top or base_memory as an
1114 // "empty" slice. See is_empty, is_empty2, and next below.
1115 //
1116 // The sparseness property is repaired in MergeMemNode::Ideal.
1117 // As long as access to a MergeMem goes through this iterator
1118 // or the memory_at accessor, flaws in the sparseness will
1119 // never be observed.
1120 //
1121 // Also, iteration_setup repairs sparseness.
1122 assert(mm->verify_sparse(), "please, no dups of base");
1123 assert(mm2==NULL || mm2->verify_sparse(), "please, no dups of base");
1125 _mm = mm;
1126 _mm_base = mm->base_memory();
1127 _mm2 = mm2;
1128 _cnt = mm->req();
1129 _idx = Compile::AliasIdxBot-1; // start at the base memory
1130 _mem = NULL;
1131 _mem2 = NULL;
1132 }
1134 #ifdef ASSERT
1135 Node* check_memory() const {
1136 if (at_base_memory())
1137 return _mm->base_memory();
1138 else if ((uint)_idx < _mm->req() && !_mm->in(_idx)->is_top())
1139 return _mm->memory_at(_idx);
1140 else
1141 return _mm_base;
1142 }
1143 Node* check_memory2() const {
1144 return at_base_memory()? _mm2->base_memory(): _mm2->memory_at(_idx);
1145 }
1146 #endif
1148 static bool match_memory(Node* mem, const MergeMemNode* mm, int idx) PRODUCT_RETURN0;
1149 void assert_synch() const {
1150 assert(!_mem || _idx >= _cnt || match_memory(_mem, _mm, _idx),
1151 "no side-effects except through the stream");
1152 }
1154 public:
1156 // expected usages:
1157 // for (MergeMemStream mms(mem->is_MergeMem()); next_non_empty(); ) { ... }
1158 // for (MergeMemStream mms(mem1, mem2); next_non_empty2(); ) { ... }
1160 // iterate over one merge
1161 MergeMemStream(MergeMemNode* mm) {
1162 mm->iteration_setup();
1163 init(mm);
1164 debug_only(_cnt2 = 999);
1165 }
1166 // iterate in parallel over two merges
1167 // only iterates through non-empty elements of mm2
1168 MergeMemStream(MergeMemNode* mm, const MergeMemNode* mm2) {
1169 assert(mm2, "second argument must be a MergeMem also");
1170 ((MergeMemNode*)mm2)->iteration_setup(); // update hidden state
1171 mm->iteration_setup(mm2);
1172 init(mm, mm2);
1173 _cnt2 = mm2->req();
1174 }
1175 #ifdef ASSERT
1176 ~MergeMemStream() {
1177 assert_synch();
1178 }
1179 #endif
1181 MergeMemNode* all_memory() const {
1182 return _mm;
1183 }
1184 Node* base_memory() const {
1185 assert(_mm_base == _mm->base_memory(), "no update to base memory, please");
1186 return _mm_base;
1187 }
1188 const MergeMemNode* all_memory2() const {
1189 assert(_mm2 != NULL, "");
1190 return _mm2;
1191 }
1192 bool at_base_memory() const {
1193 return _idx == Compile::AliasIdxBot;
1194 }
1195 int alias_idx() const {
1196 assert(_mem, "must call next 1st");
1197 return _idx;
1198 }
1200 const TypePtr* adr_type() const {
1201 return Compile::current()->get_adr_type(alias_idx());
1202 }
1204 const TypePtr* adr_type(Compile* C) const {
1205 return C->get_adr_type(alias_idx());
1206 }
1207 bool is_empty() const {
1208 assert(_mem, "must call next 1st");
1209 assert(_mem->is_top() == (_mem==_mm->empty_memory()), "correct sentinel");
1210 return _mem->is_top();
1211 }
1212 bool is_empty2() const {
1213 assert(_mem2, "must call next 1st");
1214 assert(_mem2->is_top() == (_mem2==_mm2->empty_memory()), "correct sentinel");
1215 return _mem2->is_top();
1216 }
1217 Node* memory() const {
1218 assert(!is_empty(), "must not be empty");
1219 assert_synch();
1220 return _mem;
1221 }
1222 // get the current memory, regardless of empty or non-empty status
1223 Node* force_memory() const {
1224 assert(!is_empty() || !at_base_memory(), "");
1225 // Use _mm_base to defend against updates to _mem->base_memory().
1226 Node *mem = _mem->is_top() ? _mm_base : _mem;
1227 assert(mem == check_memory(), "");
1228 return mem;
1229 }
1230 Node* memory2() const {
1231 assert(_mem2 == check_memory2(), "");
1232 return _mem2;
1233 }
1234 void set_memory(Node* mem) {
1235 if (at_base_memory()) {
1236 // Note that this does not change the invariant _mm_base.
1237 _mm->set_base_memory(mem);
1238 } else {
1239 _mm->set_memory_at(_idx, mem);
1240 }
1241 _mem = mem;
1242 assert_synch();
1243 }
1245 // Recover from a side effect to the MergeMemNode.
1246 void set_memory() {
1247 _mem = _mm->in(_idx);
1248 }
1250 bool next() { return next(false); }
1251 bool next2() { return next(true); }
1253 bool next_non_empty() { return next_non_empty(false); }
1254 bool next_non_empty2() { return next_non_empty(true); }
1255 // next_non_empty2 can yield states where is_empty() is true
1257 private:
1258 // find the next item, which might be empty
1259 bool next(bool have_mm2) {
1260 assert((_mm2 != NULL) == have_mm2, "use other next");
1261 assert_synch();
1262 if (++_idx < _cnt) {
1263 // Note: This iterator allows _mm to be non-sparse.
1264 // It behaves the same whether _mem is top or base_memory.
1265 _mem = _mm->in(_idx);
1266 if (have_mm2)
1267 _mem2 = _mm2->in((_idx < _cnt2) ? _idx : Compile::AliasIdxTop);
1268 return true;
1269 }
1270 return false;
1271 }
1273 // find the next non-empty item
1274 bool next_non_empty(bool have_mm2) {
1275 while (next(have_mm2)) {
1276 if (!is_empty()) {
1277 // make sure _mem2 is filled in sensibly
1278 if (have_mm2 && _mem2->is_top()) _mem2 = _mm2->base_memory();
1279 return true;
1280 } else if (have_mm2 && !is_empty2()) {
1281 return true; // is_empty() == true
1282 }
1283 }
1284 return false;
1285 }
1286 };
1288 //------------------------------Prefetch---------------------------------------
1290 // Non-faulting prefetch load. Prefetch for many reads.
1291 class PrefetchReadNode : public Node {
1292 public:
1293 PrefetchReadNode(Node *abio, Node *adr) : Node(0,abio,adr) {}
1294 virtual int Opcode() const;
1295 virtual uint ideal_reg() const { return NotAMachineReg; }
1296 virtual uint match_edge(uint idx) const { return idx==2; }
1297 virtual const Type *bottom_type() const { return Type::ABIO; }
1298 };
1300 // Non-faulting prefetch load. Prefetch for many reads & many writes.
1301 class PrefetchWriteNode : public Node {
1302 public:
1303 PrefetchWriteNode(Node *abio, Node *adr) : Node(0,abio,adr) {}
1304 virtual int Opcode() const;
1305 virtual uint ideal_reg() const { return NotAMachineReg; }
1306 virtual uint match_edge(uint idx) const { return idx==2; }
1307 virtual const Type *bottom_type() const { return Type::ABIO; }
1308 };
1310 // Allocation prefetch which may fault, TLAB size have to be adjusted.
1311 class PrefetchAllocationNode : public Node {
1312 public:
1313 PrefetchAllocationNode(Node *mem, Node *adr) : Node(0,mem,adr) {}
1314 virtual int Opcode() const;
1315 virtual uint ideal_reg() const { return NotAMachineReg; }
1316 virtual uint match_edge(uint idx) const { return idx==2; }
1317 virtual const Type *bottom_type() const { return ( AllocatePrefetchStyle == 3 ) ? Type::MEMORY : Type::ABIO; }
1318 };
1320 #endif // SHARE_VM_OPTO_MEMNODE_HPP