1 /*
2 * Copyright (c) 1997, 2019, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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5 * This code is free software; you can redistribute it and/or modify it
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24
25 #ifndef SHARE_OPTO_PHASEX_HPP
26 #define SHARE_OPTO_PHASEX_HPP
27
28 #include "libadt/dict.hpp"
29 #include "libadt/vectset.hpp"
30 #include "memory/resourceArea.hpp"
31 #include "opto/memnode.hpp"
32 #include "opto/node.hpp"
33 #include "opto/phase.hpp"
34 #include "opto/type.hpp"
35
36 class Compile;
37 class ConINode;
38 class ConLNode;
39 class Node;
40 class Type;
41 class PhaseTransform;
42 class PhaseGVN;
43 class PhaseIterGVN;
44 class PhaseCCP;
45 class PhasePeephole;
46 class PhaseRegAlloc;
47
48
49 //-----------------------------------------------------------------------------
50 // Expandable closed hash-table of nodes, initialized to NULL.
51 // Note that the constructor just zeros things
52 // Storage is reclaimed when the Arena's lifetime is over.
53 class NodeHash : public StackObj {
54 protected:
55 Arena *_a; // Arena to allocate in
56 uint _max; // Size of table (power of 2)
57 uint _inserts; // For grow and debug, count of hash_inserts
58 uint _insert_limit; // 'grow' when _inserts reaches _insert_limit
59 Node **_table; // Hash table of Node pointers
60 Node *_sentinel; // Replaces deleted entries in hash table
61
62 public:
63 NodeHash(uint est_max_size);
64 NodeHash(Arena *arena, uint est_max_size);
65 NodeHash(NodeHash *use_this_state);
66 #ifdef ASSERT
67 ~NodeHash(); // Unlock all nodes upon destruction of table.
68 void operator=(const NodeHash&); // Unlock all nodes upon replacement of table.
69 #endif
70 Node *hash_find(const Node*);// Find an equivalent version in hash table
71 Node *hash_find_insert(Node*);// If not in table insert else return found node
72 void hash_insert(Node*); // Insert into hash table
73 bool hash_delete(const Node*);// Replace with _sentinel in hash table
74 void check_grow() {
75 _inserts++;
76 if( _inserts == _insert_limit ) { grow(); }
77 assert( _inserts <= _insert_limit, "hash table overflow");
78 assert( _inserts < _max, "hash table overflow" );
79 }
80 static uint round_up(uint); // Round up to nearest power of 2
81 void grow(); // Grow _table to next power of 2 and rehash
82 // Return 75% of _max, rounded up.
83 uint insert_limit() const { return _max - (_max>>2); }
84
85 void clear(); // Set all entries to NULL, keep storage.
86 // Size of hash table
87 uint size() const { return _max; }
88 // Return Node* at index in table
89 Node *at(uint table_index) {
90 assert(table_index < _max, "Must be within table");
91 return _table[table_index];
92 }
93
94 void remove_useless_nodes(VectorSet &useful); // replace with sentinel
95 void replace_with(NodeHash* nh);
96 void check_no_speculative_types(); // Check no speculative part for type nodes in table
97
98 Node *sentinel() { return _sentinel; }
99
100 #ifndef PRODUCT
101 Node *find_index(uint idx); // For debugging
102 void dump(); // For debugging, dump statistics
103 uint _grows; // For debugging, count of table grow()s
104 uint _look_probes; // For debugging, count of hash probes
105 uint _lookup_hits; // For debugging, count of hash_finds
106 uint _lookup_misses; // For debugging, count of hash_finds
107 uint _insert_probes; // For debugging, count of hash probes
108 uint _delete_probes; // For debugging, count of hash probes for deletes
109 uint _delete_hits; // For debugging, count of hash probes for deletes
110 uint _delete_misses; // For debugging, count of hash probes for deletes
111 uint _total_inserts; // For debugging, total inserts into hash table
112 uint _total_insert_probes; // For debugging, total probes while inserting
113 #endif
114 };
115
116
117 //-----------------------------------------------------------------------------
118 // Map dense integer indices to Types. Uses classic doubling-array trick.
119 // Abstractly provides an infinite array of Type*'s, initialized to NULL.
120 // Note that the constructor just zeros things, and since I use Arena
121 // allocation I do not need a destructor to reclaim storage.
122 // Despite the general name, this class is customized for use by PhaseTransform.
123 class Type_Array : public StackObj {
124 Arena *_a; // Arena to allocate in
125 uint _max;
126 const Type **_types;
127 void grow( uint i ); // Grow array node to fit
128 const Type *operator[] ( uint i ) const // Lookup, or NULL for not mapped
129 { return (i<_max) ? _types[i] : (Type*)NULL; }
130 friend class PhaseTransform;
131 public:
132 Type_Array(Arena *a) : _a(a), _max(0), _types(0) {}
133 Type_Array(Type_Array *ta) : _a(ta->_a), _max(ta->_max), _types(ta->_types) { }
134 const Type *fast_lookup(uint i) const{assert(i<_max,"oob");return _types[i];}
135 // Extend the mapping: index i maps to Type *n.
136 void map( uint i, const Type *n ) { if( i>=_max ) grow(i); _types[i] = n; }
137 uint Size() const { return _max; }
138 #ifndef PRODUCT
139 void dump() const;
140 #endif
141 };
142
143
144 //------------------------------PhaseRemoveUseless-----------------------------
145 // Remove useless nodes from GVN hash-table, worklist, and graph
146 class PhaseRemoveUseless : public Phase {
147 protected:
148 Unique_Node_List _useful; // Nodes reachable from root
149 // list is allocated from current resource area
150 public:
151 PhaseRemoveUseless(PhaseGVN *gvn, Unique_Node_List *worklist, PhaseNumber phase_num = Remove_Useless);
152
153 Unique_Node_List *get_useful() { return &_useful; }
154 };
155
156 //------------------------------PhaseRenumber----------------------------------
157 // Phase that first performs a PhaseRemoveUseless, then it renumbers compiler
158 // structures accordingly.
159 class PhaseRenumberLive : public PhaseRemoveUseless {
160 protected:
161 Type_Array _new_type_array; // Storage for the updated type information.
162 GrowableArray<int> _old2new_map;
163 Node_List _delayed;
164 bool _is_pass_finished;
165 uint _live_node_count;
166
167 int update_embedded_ids(Node* n);
168 int new_index(int old_idx);
169
170 public:
171 PhaseRenumberLive(PhaseGVN* gvn,
172 Unique_Node_List* worklist, Unique_Node_List* new_worklist,
173 PhaseNumber phase_num = Remove_Useless_And_Renumber_Live);
174 };
175
176
177 //------------------------------PhaseTransform---------------------------------
178 // Phases that analyze, then transform. Constructing the Phase object does any
179 // global or slow analysis. The results are cached later for a fast
180 // transformation pass. When the Phase object is deleted the cached analysis
181 // results are deleted.
182 class PhaseTransform : public Phase {
183 protected:
184 Arena* _arena;
185 Node_List _nodes; // Map old node indices to new nodes.
186 Type_Array _types; // Map old node indices to Types.
187
188 // ConNode caches:
189 enum { _icon_min = -1 * HeapWordSize,
190 _icon_max = 16 * HeapWordSize,
191 _lcon_min = _icon_min,
192 _lcon_max = _icon_max,
193 _zcon_max = (uint)T_CONFLICT
194 };
195 ConINode* _icons[_icon_max - _icon_min + 1]; // cached jint constant nodes
196 ConLNode* _lcons[_lcon_max - _lcon_min + 1]; // cached jlong constant nodes
197 ConNode* _zcons[_zcon_max + 1]; // cached is_zero_type nodes
198 void init_con_caches();
199
200 // Support both int and long caches because either might be an intptr_t,
201 // so they show up frequently in address computations.
202
203 public:
204 PhaseTransform( PhaseNumber pnum );
205 PhaseTransform( Arena *arena, PhaseNumber pnum );
206 PhaseTransform( PhaseTransform *phase, PhaseNumber pnum );
207
208 Arena* arena() { return _arena; }
209 Type_Array& types() { return _types; }
210 void replace_types(Type_Array new_types) {
211 _types = new_types;
212 }
213 // _nodes is used in varying ways by subclasses, which define local accessors
214 uint nodes_size() {
215 return _nodes.size();
216 }
217
218 public:
219 // Get a previously recorded type for the node n.
220 // This type must already have been recorded.
221 // If you want the type of a very new (untransformed) node,
222 // you must use type_or_null, and test the result for NULL.
223 const Type* type(const Node* n) const {
224 assert(_pnum != Ideal_Loop, "should not be used from PhaseIdealLoop");
225 assert(n != NULL, "must not be null");
226 const Type* t = _types.fast_lookup(n->_idx);
227 assert(t != NULL, "must set before get");
228 return t;
229 }
230 // Get a previously recorded type for the node n,
231 // or else return NULL if there is none.
232 const Type* type_or_null(const Node* n) const {
233 assert(_pnum != Ideal_Loop, "should not be used from PhaseIdealLoop");
234 return _types.fast_lookup(n->_idx);
235 }
236 // Record a type for a node.
237 void set_type(const Node* n, const Type *t) {
238 assert(t != NULL, "type must not be null");
239 _types.map(n->_idx, t);
240 }
241 // Record an initial type for a node, the node's bottom type.
242 void set_type_bottom(const Node* n) {
243 // Use this for initialization when bottom_type() (or better) is not handy.
244 // Usually the initialization shoudl be to n->Value(this) instead,
245 // or a hand-optimized value like Type::MEMORY or Type::CONTROL.
246 assert(_types[n->_idx] == NULL, "must set the initial type just once");
247 _types.map(n->_idx, n->bottom_type());
248 }
249 // Make sure the types array is big enough to record a size for the node n.
250 // (In product builds, we never want to do range checks on the types array!)
251 void ensure_type_or_null(const Node* n) {
252 if (n->_idx >= _types.Size())
253 _types.map(n->_idx, NULL); // Grow the types array as needed.
254 }
255
256 // Utility functions:
257 const TypeInt* find_int_type( Node* n);
258 const TypeLong* find_long_type(Node* n);
259 jint find_int_con( Node* n, jint value_if_unknown) {
260 const TypeInt* t = find_int_type(n);
261 return (t != NULL && t->is_con()) ? t->get_con() : value_if_unknown;
262 }
263 jlong find_long_con(Node* n, jlong value_if_unknown) {
264 const TypeLong* t = find_long_type(n);
265 return (t != NULL && t->is_con()) ? t->get_con() : value_if_unknown;
266 }
267
268 // Make an idealized constant, i.e., one of ConINode, ConPNode, ConFNode, etc.
269 // Same as transform(ConNode::make(t)).
270 ConNode* makecon(const Type* t);
271 virtual ConNode* uncached_makecon(const Type* t) // override in PhaseValues
272 { ShouldNotCallThis(); return NULL; }
273
274 // Fast int or long constant. Same as TypeInt::make(i) or TypeLong::make(l).
275 ConINode* intcon(jint i);
276 ConLNode* longcon(jlong l);
277
278 // Fast zero or null constant. Same as makecon(Type::get_zero_type(bt)).
279 ConNode* zerocon(BasicType bt);
280
281 // Return a node which computes the same function as this node, but
282 // in a faster or cheaper fashion.
283 virtual Node *transform( Node *n ) = 0;
284
285 // Return whether two Nodes are equivalent.
286 // Must not be recursive, since the recursive version is built from this.
287 // For pessimistic optimizations this is simply pointer equivalence.
288 bool eqv(const Node* n1, const Node* n2) const { return n1 == n2; }
289
290 // For pessimistic passes, the return type must monotonically narrow.
291 // For optimistic passes, the return type must monotonically widen.
292 // It is possible to get into a "death march" in either type of pass,
293 // where the types are continually moving but it will take 2**31 or
294 // more steps to converge. This doesn't happen on most normal loops.
295 //
296 // Here is an example of a deadly loop for an optimistic pass, along
297 // with a partial trace of inferred types:
298 // x = phi(0,x'); L: x' = x+1; if (x' >= 0) goto L;
299 // 0 1 join([0..max], 1)
300 // [0..1] [1..2] join([0..max], [1..2])
301 // [0..2] [1..3] join([0..max], [1..3])
302 // ... ... ...
303 // [0..max] [min]u[1..max] join([0..max], [min..max])
304 // [0..max] ==> fixpoint
305 // We would have proven, the hard way, that the iteration space is all
306 // non-negative ints, with the loop terminating due to 32-bit overflow.
307 //
308 // Here is the corresponding example for a pessimistic pass:
309 // x = phi(0,x'); L: x' = x-1; if (x' >= 0) goto L;
310 // int int join([0..max], int)
311 // [0..max] [-1..max-1] join([0..max], [-1..max-1])
312 // [0..max-1] [-1..max-2] join([0..max], [-1..max-2])
313 // ... ... ...
314 // [0..1] [-1..0] join([0..max], [-1..0])
315 // 0 -1 join([0..max], -1)
316 // 0 == fixpoint
317 // We would have proven, the hard way, that the iteration space is {0}.
318 // (Usually, other optimizations will make the "if (x >= 0)" fold up
319 // before we get into trouble. But not always.)
320 //
321 // It's a pleasant thing to observe that the pessimistic pass
322 // will make short work of the optimistic pass's deadly loop,
323 // and vice versa. That is a good example of the complementary
324 // purposes of the CCP (optimistic) vs. GVN (pessimistic) phases.
325 //
326 // In any case, only widen or narrow a few times before going to the
327 // correct flavor of top or bottom.
328 //
329 // This call only needs to be made once as the data flows around any
330 // given cycle. We do it at Phis, and nowhere else.
331 // The types presented are the new type of a phi (computed by PhiNode::Value)
332 // and the previously computed type, last time the phi was visited.
333 //
334 // The third argument is upper limit for the saturated value,
335 // if the phase wishes to widen the new_type.
336 // If the phase is narrowing, the old type provides a lower limit.
337 // Caller guarantees that old_type and new_type are no higher than limit_type.
338 virtual const Type* saturate(const Type* new_type, const Type* old_type,
339 const Type* limit_type) const
340 { ShouldNotCallThis(); return NULL; }
341
342 // Delayed node rehash if this is an IGVN phase
343 virtual void igvn_rehash_node_delayed(Node* n) {}
344
345 // true if CFG node d dominates CFG node n
346 virtual bool is_dominator(Node *d, Node *n) { fatal("unimplemented for this pass"); return false; };
347
348 #ifndef PRODUCT
349 void dump_old2new_map() const;
350 void dump_new( uint new_lidx ) const;
351 void dump_types() const;
352 void dump_nodes_and_types(const Node *root, uint depth, bool only_ctrl = true);
353 void dump_nodes_and_types_recur( const Node *n, uint depth, bool only_ctrl, VectorSet &visited);
354
355 uint _count_progress; // For profiling, count transforms that make progress
356 void set_progress() { ++_count_progress; assert( allow_progress(),"No progress allowed during verification"); }
357 void clear_progress() { _count_progress = 0; }
358 uint made_progress() const { return _count_progress; }
359
360 uint _count_transforms; // For profiling, count transforms performed
361 void set_transforms() { ++_count_transforms; }
362 void clear_transforms() { _count_transforms = 0; }
363 uint made_transforms() const{ return _count_transforms; }
364
365 bool _allow_progress; // progress not allowed during verification pass
366 void set_allow_progress(bool allow) { _allow_progress = allow; }
367 bool allow_progress() { return _allow_progress; }
368 #endif
369 };
370
371 //------------------------------PhaseValues------------------------------------
372 // Phase infrastructure to support values
373 class PhaseValues : public PhaseTransform {
374 protected:
375 NodeHash _table; // Hash table for value-numbering
376
377 public:
378 PhaseValues( Arena *arena, uint est_max_size );
379 PhaseValues( PhaseValues *pt );
380 PhaseValues( PhaseValues *ptv, const char *dummy );
381 NOT_PRODUCT( ~PhaseValues(); )
382 virtual PhaseIterGVN *is_IterGVN() { return 0; }
383
384 // Some Ideal and other transforms delete --> modify --> insert values
385 bool hash_delete(Node *n) { return _table.hash_delete(n); }
386 void hash_insert(Node *n) { _table.hash_insert(n); }
387 Node *hash_find_insert(Node *n){ return _table.hash_find_insert(n); }
388 Node *hash_find(const Node *n) { return _table.hash_find(n); }
389
390 // Used after parsing to eliminate values that are no longer in program
391 void remove_useless_nodes(VectorSet &useful) {
392 _table.remove_useless_nodes(useful);
393 // this may invalidate cached cons so reset the cache
394 init_con_caches();
395 }
396
397 virtual ConNode* uncached_makecon(const Type* t); // override from PhaseTransform
398
399 virtual const Type* saturate(const Type* new_type, const Type* old_type,
400 const Type* limit_type) const
401 { return new_type; }
402
403 #ifndef PRODUCT
404 uint _count_new_values; // For profiling, count new values produced
405 void inc_new_values() { ++_count_new_values; }
406 void clear_new_values() { _count_new_values = 0; }
407 uint made_new_values() const { return _count_new_values; }
408 #endif
409 };
410
411
412 //------------------------------PhaseGVN---------------------------------------
413 // Phase for performing local, pessimistic GVN-style optimizations.
414 class PhaseGVN : public PhaseValues {
415 protected:
416 bool is_dominator_helper(Node *d, Node *n, bool linear_only);
417
418 public:
419 PhaseGVN( Arena *arena, uint est_max_size ) : PhaseValues( arena, est_max_size ) {}
420 PhaseGVN( PhaseGVN *gvn ) : PhaseValues( gvn ) {}
421 PhaseGVN( PhaseGVN *gvn, const char *dummy ) : PhaseValues( gvn, dummy ) {}
422
423 // Return a node which computes the same function as this node, but
424 // in a faster or cheaper fashion.
425 Node *transform( Node *n );
426 Node *transform_no_reclaim( Node *n );
427 virtual void record_for_igvn(Node *n) {
428 C->record_for_igvn(n);
429 }
430
431 void replace_with(PhaseGVN* gvn) {
432 _table.replace_with(&gvn->_table);
433 _types = gvn->_types;
434 }
435
436 bool is_dominator(Node *d, Node *n) { return is_dominator_helper(d, n, true); }
437
438 // Helper to call Node::Ideal() and BarrierSetC2::ideal_node().
439 Node* apply_ideal(Node* i, bool can_reshape);
440
441 // Helper to call Node::Identity() and BarrierSetC2::identity_node().
442 Node* apply_identity(Node* n);
443
444 // Check for a simple dead loop when a data node references itself.
445 DEBUG_ONLY(void dead_loop_check(Node *n);)
446 };
447
448 //------------------------------PhaseIterGVN-----------------------------------
449 // Phase for iteratively performing local, pessimistic GVN-style optimizations.
450 // and ideal transformations on the graph.
451 class PhaseIterGVN : public PhaseGVN {
452 private:
453 bool _delay_transform; // When true simply register the node when calling transform
454 // instead of actually optimizing it
455
456 // Idealize old Node 'n' with respect to its inputs and its value
457 virtual Node *transform_old( Node *a_node );
458
459 // Subsume users of node 'old' into node 'nn'
460 void subsume_node( Node *old, Node *nn );
461
462 Node_Stack _stack; // Stack used to avoid recursion
463
464 protected:
465
466 // Warm up hash table, type table and initial worklist
467 void init_worklist( Node *a_root );
468
469 virtual const Type* saturate(const Type* new_type, const Type* old_type,
470 const Type* limit_type) const;
471 // Usually returns new_type. Returns old_type if new_type is only a slight
472 // improvement, such that it would take many (>>10) steps to reach 2**32.
473
474 public:
475 PhaseIterGVN( PhaseIterGVN *igvn ); // Used by CCP constructor
476 PhaseIterGVN( PhaseGVN *gvn ); // Used after Parser
477 PhaseIterGVN( PhaseIterGVN *igvn, const char *dummy ); // Used after +VerifyOpto
478
479 // Idealize new Node 'n' with respect to its inputs and its value
480 virtual Node *transform( Node *a_node );
481 virtual void record_for_igvn(Node *n) { }
482
483 virtual PhaseIterGVN *is_IterGVN() { return this; }
484
485 Unique_Node_List _worklist; // Iterative worklist
486
487 // Given def-use info and an initial worklist, apply Node::Ideal,
488 // Node::Value, Node::Identity, hash-based value numbering, Node::Ideal_DU
489 // and dominator info to a fixed point.
490 void optimize();
491
492 #ifndef PRODUCT
493 void trace_PhaseIterGVN(Node* n, Node* nn, const Type* old_type);
494 void init_verifyPhaseIterGVN();
495 void verify_PhaseIterGVN();
496 #endif
497
498 #ifdef ASSERT
499 void dump_infinite_loop_info(Node* n);
500 void trace_PhaseIterGVN_verbose(Node* n, int num_processed);
501 #endif
502
503 // Register a new node with the iter GVN pass without transforming it.
504 // Used when we need to restructure a Region/Phi area and all the Regions
505 // and Phis need to complete this one big transform before any other
506 // transforms can be triggered on the region.
507 // Optional 'orig' is an earlier version of this node.
508 // It is significant only for debugging and profiling.
509 Node* register_new_node_with_optimizer(Node* n, Node* orig = NULL);
510
511 // Kill a globally dead Node. All uses are also globally dead and are
512 // aggressively trimmed.
513 void remove_globally_dead_node( Node *dead );
514
515 // Kill all inputs to a dead node, recursively making more dead nodes.
516 // The Node must be dead locally, i.e., have no uses.
517 void remove_dead_node( Node *dead ) {
518 assert(dead->outcnt() == 0 && !dead->is_top(), "node must be dead");
519 remove_globally_dead_node(dead);
520 }
521
522 // Add users of 'n' to worklist
523 void add_users_to_worklist0( Node *n );
524 void add_users_to_worklist ( Node *n );
525
526 // Replace old node with new one.
527 void replace_node( Node *old, Node *nn ) {
528 add_users_to_worklist(old);
529 hash_delete(old); // Yank from hash before hacking edges
530 subsume_node(old, nn);
531 }
532
533 // Delayed node rehash: remove a node from the hash table and rehash it during
534 // next optimizing pass
535 void rehash_node_delayed(Node* n) {
536 hash_delete(n);
537 _worklist.push(n);
538 }
539
540 void igvn_rehash_node_delayed(Node* n) {
541 rehash_node_delayed(n);
542 }
543
544 // Replace ith edge of "n" with "in"
545 void replace_input_of(Node* n, int i, Node* in) {
546 rehash_node_delayed(n);
547 n->set_req(i, in);
548 }
549
550 // Delete ith edge of "n"
551 void delete_input_of(Node* n, int i) {
552 rehash_node_delayed(n);
553 n->del_req(i);
554 }
555
556 bool delay_transform() const { return _delay_transform; }
557
558 void set_delay_transform(bool delay) {
559 _delay_transform = delay;
560 }
561
562 // Clone loop predicates. Defined in loopTransform.cpp.
563 Node* clone_loop_predicates(Node* old_entry, Node* new_entry, bool clone_limit_check);
564 // Create a new if below new_entry for the predicate to be cloned
565 ProjNode* create_new_if_for_predicate(ProjNode* cont_proj, Node* new_entry,
566 Deoptimization::DeoptReason reason,
567 int opcode);
568
569 void remove_speculative_types();
570 void check_no_speculative_types() {
571 _table.check_no_speculative_types();
572 }
573
574 bool is_dominator(Node *d, Node *n) { return is_dominator_helper(d, n, false); }
575
576 #ifndef PRODUCT
577 protected:
578 // Sub-quadratic implementation of VerifyIterativeGVN.
579 julong _verify_counter;
580 julong _verify_full_passes;
581 enum { _verify_window_size = 30 };
582 Node* _verify_window[_verify_window_size];
583 void verify_step(Node* n);
584 #endif
585 };
586
587 //------------------------------PhaseCCP---------------------------------------
588 // Phase for performing global Conditional Constant Propagation.
589 // Should be replaced with combined CCP & GVN someday.
590 class PhaseCCP : public PhaseIterGVN {
591 // Non-recursive. Use analysis to transform single Node.
592 virtual Node *transform_once( Node *n );
593
594 public:
595 PhaseCCP( PhaseIterGVN *igvn ); // Compute conditional constants
596 NOT_PRODUCT( ~PhaseCCP(); )
597
598 // Worklist algorithm identifies constants
599 void analyze();
600 // Recursive traversal of program. Used analysis to modify program.
601 virtual Node *transform( Node *n );
602 // Do any transformation after analysis
603 void do_transform();
604
605 virtual const Type* saturate(const Type* new_type, const Type* old_type,
606 const Type* limit_type) const;
607 // Returns new_type->widen(old_type), which increments the widen bits until
608 // giving up with TypeInt::INT or TypeLong::LONG.
609 // Result is clipped to limit_type if necessary.
610
611 #ifndef PRODUCT
612 static uint _total_invokes; // For profiling, count invocations
613 void inc_invokes() { ++PhaseCCP::_total_invokes; }
614
615 static uint _total_constants; // For profiling, count constants found
616 uint _count_constants;
617 void clear_constants() { _count_constants = 0; }
618 void inc_constants() { ++_count_constants; }
619 uint count_constants() const { return _count_constants; }
620
621 static void print_statistics();
622 #endif
623 };
624
625
626 //------------------------------PhasePeephole----------------------------------
627 // Phase for performing peephole optimizations on register allocated basic blocks.
628 class PhasePeephole : public PhaseTransform {
629 PhaseRegAlloc *_regalloc;
630 PhaseCFG &_cfg;
631 // Recursive traversal of program. Pure function is unused in this phase
632 virtual Node *transform( Node *n );
633
634 public:
635 PhasePeephole( PhaseRegAlloc *regalloc, PhaseCFG &cfg );
636 NOT_PRODUCT( ~PhasePeephole(); )
637
638 // Do any transformation after analysis
639 void do_transform();
640
641 #ifndef PRODUCT
642 static uint _total_peepholes; // For profiling, count peephole rules applied
643 uint _count_peepholes;
644 void clear_peepholes() { _count_peepholes = 0; }
645 void inc_peepholes() { ++_count_peepholes; }
646 uint count_peepholes() const { return _count_peepholes; }
647
648 static void print_statistics();
649 #endif
650 };
651
652 #endif // SHARE_OPTO_PHASEX_HPP