1 /*
2 * Copyright (c) 1997, 2023, 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 *
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23 */
24
25 #ifndef SHARE_OPTO_CFGNODE_HPP
26 #define SHARE_OPTO_CFGNODE_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 // Optimization - Graph Style
36
37 class Matcher;
38 class Node;
39 class RegionNode;
40 class TypeNode;
41 class PhiNode;
42 class GotoNode;
43 class MultiNode;
44 class MultiBranchNode;
45 class IfNode;
46 class PCTableNode;
47 class JumpNode;
48 class CatchNode;
49 class NeverBranchNode;
50 class BlackholeNode;
51 class ProjNode;
52 class CProjNode;
53 class IfTrueNode;
54 class IfFalseNode;
55 class CatchProjNode;
56 class JProjNode;
57 class JumpProjNode;
58 class SCMemProjNode;
59 class PhaseIdealLoop;
60
61 // The success projection of a Parse Predicate is always an IfTrueNode and the uncommon projection an IfFalseNode
62 typedef IfTrueNode ParsePredicateSuccessProj;
63 typedef IfFalseNode ParsePredicateUncommonProj;
64
65 //------------------------------RegionNode-------------------------------------
66 // The class of RegionNodes, which can be mapped to basic blocks in the
67 // program. Their inputs point to Control sources. PhiNodes (described
68 // below) have an input point to a RegionNode. Merged data inputs to PhiNodes
69 // correspond 1-to-1 with RegionNode inputs. The zero input of a PhiNode is
70 // the RegionNode, and the zero input of the RegionNode is itself.
71 class RegionNode : public Node {
72 public:
73 enum LoopStatus {
74 // No guarantee: the region may be an irreducible loop entry, thus we have to
75 // be careful when removing entry control to it.
76 MaybeIrreducibleEntry,
77 // Limited guarantee: this region may be (nested) inside an irreducible loop,
78 // but it will never be an irreducible loop entry.
79 NeverIrreducibleEntry,
80 // Strong guarantee: this region is not (nested) inside an irreducible loop.
81 Reducible,
82 };
83
84 private:
85 bool _is_unreachable_region;
86 LoopStatus _loop_status;
87
88 bool is_possible_unsafe_loop(const PhaseGVN* phase) const;
89 bool is_unreachable_from_root(const PhaseGVN* phase) const;
90 public:
91 // Node layout (parallels PhiNode):
92 enum { Region, // Generally points to self.
93 Control // Control arcs are [1..len)
94 };
95
96 RegionNode(uint required)
97 : Node(required),
98 _is_unreachable_region(false),
99 _loop_status(LoopStatus::NeverIrreducibleEntry)
100 {
101 init_class_id(Class_Region);
102 init_req(0, this);
103 }
104
105 Node* is_copy() const {
106 const Node* r = _in[Region];
107 if (r == nullptr)
108 return nonnull_req();
109 return nullptr; // not a copy!
110 }
111 PhiNode* has_phi() const; // returns an arbitrary phi user, or null
112 PhiNode* has_unique_phi() const; // returns the unique phi user, or null
113 // Is this region node unreachable from root?
114 bool is_unreachable_region(const PhaseGVN* phase);
115 #ifdef ASSERT
116 bool is_in_infinite_subgraph();
117 static bool are_all_nodes_in_infinite_subgraph(Unique_Node_List& worklist);
118 #endif //ASSERT
119 LoopStatus loop_status() const { return _loop_status; };
120 void set_loop_status(LoopStatus status);
121 DEBUG_ONLY(void verify_can_be_irreducible_entry() const;)
122
123 virtual int Opcode() const;
124 virtual uint size_of() const { return sizeof(*this); }
125 virtual bool pinned() const { return (const Node*)in(0) == this; }
126 virtual bool is_CFG() const { return true; }
127 virtual uint hash() const { return NO_HASH; } // CFG nodes do not hash
128 virtual bool depends_only_on_test() const { return false; }
129 virtual const Type* bottom_type() const { return Type::CONTROL; }
130 virtual const Type* Value(PhaseGVN* phase) const;
131 virtual Node* Identity(PhaseGVN* phase);
132 virtual Node* Ideal(PhaseGVN* phase, bool can_reshape);
133 void remove_unreachable_subgraph(PhaseIterGVN* igvn);
134 virtual const RegMask &out_RegMask() const;
135 bool is_diamond() const;
136 void try_clean_mem_phis(PhaseIterGVN* phase);
137 bool optimize_trichotomy(PhaseIterGVN* igvn);
138 NOT_PRODUCT(virtual void dump_spec(outputStream* st) const;)
139 };
140
141 //------------------------------JProjNode--------------------------------------
142 // jump projection for node that produces multiple control-flow paths
143 class JProjNode : public ProjNode {
144 public:
145 JProjNode( Node* ctrl, uint idx ) : ProjNode(ctrl,idx) {}
146 virtual int Opcode() const;
147 virtual bool is_CFG() const { return true; }
148 virtual uint hash() const { return NO_HASH; } // CFG nodes do not hash
149 virtual const Node* is_block_proj() const { return in(0); }
150 virtual const RegMask& out_RegMask() const;
151 virtual uint ideal_reg() const { return 0; }
152 };
153
154 //------------------------------PhiNode----------------------------------------
155 // PhiNodes merge values from different Control paths. Slot 0 points to the
156 // controlling RegionNode. Other slots map 1-for-1 with incoming control flow
157 // paths to the RegionNode.
158 class PhiNode : public TypeNode {
159 friend class PhaseRenumberLive;
160
161 const TypePtr* const _adr_type; // non-null only for Type::MEMORY nodes.
162 // The following fields are only used for data PhiNodes to indicate
163 // that the PhiNode represents the value of a known instance field.
164 int _inst_mem_id; // Instance memory id (node index of the memory Phi)
165 int _inst_id; // Instance id of the memory slice.
166 const int _inst_index; // Alias index of the instance memory slice.
167 // Array elements references have the same alias_idx but different offset.
168 const int _inst_offset; // Offset of the instance memory slice.
169 // Size is bigger to hold the _adr_type field.
170 virtual uint hash() const; // Check the type
171 virtual bool cmp( const Node &n ) const;
172 virtual uint size_of() const { return sizeof(*this); }
173
174 // Determine if CMoveNode::is_cmove_id can be used at this join point.
175 Node* is_cmove_id(PhaseTransform* phase, int true_path);
176 bool wait_for_region_igvn(PhaseGVN* phase);
177 bool is_data_loop(RegionNode* r, Node* uin, const PhaseGVN* phase);
178
179 static Node* clone_through_phi(Node* root_phi, const Type* t, uint c, PhaseIterGVN* igvn);
180 static Node* merge_through_phi(Node* root_phi, PhaseIterGVN* igvn);
181
182 bool must_wait_for_region_in_irreducible_loop(PhaseGVN* phase) const;
183
184 public:
185 // Node layout (parallels RegionNode):
186 enum { Region, // Control input is the Phi's region.
187 Input // Input values are [1..len)
188 };
189
190 PhiNode( Node *r, const Type *t, const TypePtr* at = nullptr,
191 const int imid = -1,
192 const int iid = TypeOopPtr::InstanceTop,
193 const int iidx = Compile::AliasIdxTop,
194 const int ioffs = Type::OffsetTop )
195 : TypeNode(t,r->req()),
196 _adr_type(at),
197 _inst_mem_id(imid),
198 _inst_id(iid),
199 _inst_index(iidx),
200 _inst_offset(ioffs)
201 {
202 init_class_id(Class_Phi);
203 init_req(0, r);
204 verify_adr_type();
205 }
206 // create a new phi with in edges matching r and set (initially) to x
207 static PhiNode* make( Node* r, Node* x );
208 // extra type arguments override the new phi's bottom_type and adr_type
209 static PhiNode* make( Node* r, Node* x, const Type *t, const TypePtr* at = nullptr );
210 // create a new phi with narrowed memory type
211 PhiNode* slice_memory(const TypePtr* adr_type) const;
212 PhiNode* split_out_instance(const TypePtr* at, PhaseIterGVN *igvn) const;
213 // like make(r, x), but does not initialize the in edges to x
214 static PhiNode* make_blank( Node* r, Node* x );
215
216 // Accessors
217 RegionNode* region() const { Node* r = in(Region); assert(!r || r->is_Region(), ""); return (RegionNode*)r; }
218
219 bool is_tripcount(BasicType bt) const;
220
221 // Determine a unique non-trivial input, if any.
222 // Ignore casts if it helps. Return null on failure.
223 Node* unique_input(PhaseValues* phase, bool uncast);
224 Node* unique_input(PhaseValues* phase) {
225 Node* uin = unique_input(phase, false);
226 if (uin == nullptr) {
227 uin = unique_input(phase, true);
228 }
229 return uin;
230 }
231
232 // Check for a simple dead loop.
233 enum LoopSafety { Safe = 0, Unsafe, UnsafeLoop };
234 LoopSafety simple_data_loop_check(Node *in) const;
235 // Is it unsafe data loop? It becomes a dead loop if this phi node removed.
236 bool is_unsafe_data_reference(Node *in) const;
237 int is_diamond_phi() const;
238 bool try_clean_memory_phi(PhaseIterGVN* igvn);
239 virtual int Opcode() const;
240 virtual bool pinned() const { return in(0) != 0; }
241 virtual const TypePtr *adr_type() const { verify_adr_type(true); return _adr_type; }
242
243 void set_inst_mem_id(int inst_mem_id) { _inst_mem_id = inst_mem_id; }
244 int inst_mem_id() const { return _inst_mem_id; }
245 int inst_id() const { return _inst_id; }
246 int inst_index() const { return _inst_index; }
247 int inst_offset() const { return _inst_offset; }
248 bool is_same_inst_field(const Type* tp, int mem_id, int id, int index, int offset) {
249 return type()->basic_type() == tp->basic_type() &&
250 inst_mem_id() == mem_id &&
251 inst_id() == id &&
252 inst_index() == index &&
253 inst_offset() == offset &&
254 type()->higher_equal(tp);
255 }
256
257 InlineTypeNode* push_inline_types_through(PhaseGVN* phase, bool can_reshape, ciInlineKlass* vk);
258
259 virtual const Type* Value(PhaseGVN* phase) const;
260 virtual Node* Identity(PhaseGVN* phase);
261 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
262 virtual const RegMask &out_RegMask() const;
263 virtual const RegMask &in_RegMask(uint) const;
264 #ifndef PRODUCT
265 virtual void dump_spec(outputStream *st) const;
266 #endif
267 #ifdef ASSERT
268 void verify_adr_type(VectorSet& visited, const TypePtr* at) const;
269 void verify_adr_type(bool recursive = false) const;
270 #else //ASSERT
271 void verify_adr_type(bool recursive = false) const {}
272 #endif //ASSERT
273 };
274
275 //------------------------------GotoNode---------------------------------------
276 // GotoNodes perform direct branches.
277 class GotoNode : public Node {
278 public:
279 GotoNode( Node *control ) : Node(control) {}
280 virtual int Opcode() const;
281 virtual bool pinned() const { return true; }
282 virtual bool is_CFG() const { return true; }
283 virtual uint hash() const { return NO_HASH; } // CFG nodes do not hash
284 virtual const Node *is_block_proj() const { return this; }
285 virtual bool depends_only_on_test() const { return false; }
286 virtual const Type *bottom_type() const { return Type::CONTROL; }
287 virtual const Type* Value(PhaseGVN* phase) const;
288 virtual Node* Identity(PhaseGVN* phase);
289 virtual const RegMask &out_RegMask() const;
290 };
291
292 //------------------------------CProjNode--------------------------------------
293 // control projection for node that produces multiple control-flow paths
294 class CProjNode : public ProjNode {
295 public:
296 CProjNode( Node *ctrl, uint idx ) : ProjNode(ctrl,idx) {}
297 virtual int Opcode() const;
298 virtual bool is_CFG() const { return true; }
299 virtual uint hash() const { return NO_HASH; } // CFG nodes do not hash
300 virtual const Node *is_block_proj() const { return in(0); }
301 virtual const RegMask &out_RegMask() const;
302 virtual uint ideal_reg() const { return 0; }
303 };
304
305 //---------------------------MultiBranchNode-----------------------------------
306 // This class defines a MultiBranchNode, a MultiNode which yields multiple
307 // control values. These are distinguished from other types of MultiNodes
308 // which yield multiple values, but control is always and only projection #0.
309 class MultiBranchNode : public MultiNode {
310 public:
311 MultiBranchNode( uint required ) : MultiNode(required) {
312 init_class_id(Class_MultiBranch);
313 }
314 // returns required number of users to be well formed.
315 virtual int required_outcnt() const = 0;
316 };
317
318 //------------------------------IfNode-----------------------------------------
319 // Output selected Control, based on a boolean test
320 class IfNode : public MultiBranchNode {
321 // Size is bigger to hold the probability field. However, _prob does not
322 // change the semantics so it does not appear in the hash & cmp functions.
323 virtual uint size_of() const { return sizeof(*this); }
324
325 private:
326 // Helper methods for fold_compares
327 bool cmpi_folds(PhaseIterGVN* igvn, bool fold_ne = false);
328 bool is_ctrl_folds(Node* ctrl, PhaseIterGVN* igvn);
329 bool has_shared_region(ProjNode* proj, ProjNode*& success, ProjNode*& fail);
330 bool has_only_uncommon_traps(ProjNode* proj, ProjNode*& success, ProjNode*& fail, PhaseIterGVN* igvn);
331 Node* merge_uncommon_traps(ProjNode* proj, ProjNode* success, ProjNode* fail, PhaseIterGVN* igvn);
332 static void improve_address_types(Node* l, Node* r, ProjNode* fail, PhaseIterGVN* igvn);
333 bool is_cmp_with_loadrange(ProjNode* proj);
334 bool is_null_check(ProjNode* proj, PhaseIterGVN* igvn);
335 bool is_side_effect_free_test(ProjNode* proj, PhaseIterGVN* igvn);
336 void reroute_side_effect_free_unc(ProjNode* proj, ProjNode* dom_proj, PhaseIterGVN* igvn);
337 ProjNode* uncommon_trap_proj(CallStaticJavaNode*& call) const;
338 bool fold_compares_helper(ProjNode* proj, ProjNode* success, ProjNode* fail, PhaseIterGVN* igvn);
339 static bool is_dominator_unc(CallStaticJavaNode* dom_unc, CallStaticJavaNode* unc);
340
341 protected:
342 ProjNode* range_check_trap_proj(int& flip, Node*& l, Node*& r);
343 Node* Ideal_common(PhaseGVN *phase, bool can_reshape);
344 Node* search_identical(int dist, PhaseIterGVN* igvn);
345
346 Node* simple_subsuming(PhaseIterGVN* igvn);
347
348 public:
349
350 // Degrees of branch prediction probability by order of magnitude:
351 // PROB_UNLIKELY_1e(N) is a 1 in 1eN chance.
352 // PROB_LIKELY_1e(N) is a 1 - PROB_UNLIKELY_1e(N)
353 #define PROB_UNLIKELY_MAG(N) (1e- ## N ## f)
354 #define PROB_LIKELY_MAG(N) (1.0f-PROB_UNLIKELY_MAG(N))
355
356 // Maximum and minimum branch prediction probabilties
357 // 1 in 1,000,000 (magnitude 6)
358 //
359 // Although PROB_NEVER == PROB_MIN and PROB_ALWAYS == PROB_MAX
360 // they are used to distinguish different situations:
361 //
362 // The name PROB_MAX (PROB_MIN) is for probabilities which correspond to
363 // very likely (unlikely) but with a concrete possibility of a rare
364 // contrary case. These constants would be used for pinning
365 // measurements, and as measures for assertions that have high
366 // confidence, but some evidence of occasional failure.
367 //
368 // The name PROB_ALWAYS (PROB_NEVER) is to stand for situations for which
369 // there is no evidence at all that the contrary case has ever occurred.
370
371 #define PROB_NEVER PROB_UNLIKELY_MAG(6)
372 #define PROB_ALWAYS PROB_LIKELY_MAG(6)
373
374 #define PROB_MIN PROB_UNLIKELY_MAG(6)
375 #define PROB_MAX PROB_LIKELY_MAG(6)
376
377 // Static branch prediction probabilities
378 // 1 in 10 (magnitude 1)
379 #define PROB_STATIC_INFREQUENT PROB_UNLIKELY_MAG(1)
380 #define PROB_STATIC_FREQUENT PROB_LIKELY_MAG(1)
381
382 // Fair probability 50/50
383 #define PROB_FAIR (0.5f)
384
385 // Unknown probability sentinel
386 #define PROB_UNKNOWN (-1.0f)
387
388 // Probability "constructors", to distinguish as a probability any manifest
389 // constant without a names
390 #define PROB_LIKELY(x) ((float) (x))
391 #define PROB_UNLIKELY(x) (1.0f - (float)(x))
392
393 // Other probabilities in use, but without a unique name, are documented
394 // here for lack of a better place:
395 //
396 // 1 in 1000 probabilities (magnitude 3):
397 // threshold for converting to conditional move
398 // likelihood of null check failure if a null HAS been seen before
399 // likelihood of slow path taken in library calls
400 //
401 // 1 in 10,000 probabilities (magnitude 4):
402 // threshold for making an uncommon trap probability more extreme
403 // threshold for for making a null check implicit
404 // likelihood of needing a gc if eden top moves during an allocation
405 // likelihood of a predicted call failure
406 //
407 // 1 in 100,000 probabilities (magnitude 5):
408 // threshold for ignoring counts when estimating path frequency
409 // likelihood of FP clipping failure
410 // likelihood of catching an exception from a try block
411 // likelihood of null check failure if a null has NOT been seen before
412 //
413 // Magic manifest probabilities such as 0.83, 0.7, ... can be found in
414 // gen_subtype_check() and catch_inline_exceptions().
415
416 float _prob; // Probability of true path being taken.
417 float _fcnt; // Frequency counter
418 IfNode( Node *control, Node *b, float p, float fcnt )
419 : MultiBranchNode(2), _prob(p), _fcnt(fcnt) {
420 init_class_id(Class_If);
421 init_req(0,control);
422 init_req(1,b);
423 }
424 virtual int Opcode() const;
425 virtual bool pinned() const { return true; }
426 virtual const Type *bottom_type() const { return TypeTuple::IFBOTH; }
427 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
428 virtual const Type* Value(PhaseGVN* phase) const;
429 virtual int required_outcnt() const { return 2; }
430 virtual const RegMask &out_RegMask() const;
431 Node* fold_compares(PhaseIterGVN* phase);
432 static Node* up_one_dom(Node* curr, bool linear_only = false);
433 Node* dominated_by(Node* prev_dom, PhaseIterGVN* igvn);
434
435 // Takes the type of val and filters it through the test represented
436 // by if_proj and returns a more refined type if one is produced.
437 // Returns null is it couldn't improve the type.
438 static const TypeInt* filtered_int_type(PhaseGVN* phase, Node* val, Node* if_proj);
439
440 bool is_flat_array_check(PhaseTransform* phase, Node** array = nullptr);
441
442 #ifndef PRODUCT
443 virtual void dump_spec(outputStream *st) const;
444 #endif
445
446 bool same_condition(const Node* dom, PhaseIterGVN* igvn) const;
447 };
448
449 class RangeCheckNode : public IfNode {
450 private:
451 int is_range_check(Node* &range, Node* &index, jint &offset);
452
453 public:
454 RangeCheckNode(Node* control, Node *b, float p, float fcnt)
455 : IfNode(control, b, p, fcnt) {
456 init_class_id(Class_RangeCheck);
457 }
458
459 virtual int Opcode() const;
460 virtual Node* Ideal(PhaseGVN *phase, bool can_reshape);
461 };
462
463 // Special node that denotes a Parse Predicate added during parsing. A Parse Predicate serves as placeholder to later
464 // create Regular Predicates (Runtime Predicates with possible Assertion Predicates) above it. Together they form a
465 // Predicate Block. The Parse Predicate and Regular Predicates share the same uncommon trap.
466 // There are three kinds of Parse Predicates:
467 // Loop Parse Predicate, Profiled Loop Parse Predicate (both used by Loop Predication), and Loop Limit Check Parse
468 // Predicate (used for integer overflow checks when creating a counted loop).
469 // More information about predicates can be found in loopPredicate.cpp.
470 class ParsePredicateNode : public IfNode {
471 Deoptimization::DeoptReason _deopt_reason;
472 bool _useless; // If the associated loop dies, this parse predicate becomes useless and can be cleaned up by Value().
473 public:
474 ParsePredicateNode(Node* control, Deoptimization::DeoptReason deopt_reason, PhaseGVN* gvn);
475 virtual int Opcode() const;
476 virtual uint size_of() const { return sizeof(*this); }
477
478 Deoptimization::DeoptReason deopt_reason() const {
479 return _deopt_reason;
480 }
481
482 bool is_useless() const {
483 return _useless;
484 }
485
486 void mark_useless() {
487 _useless = true;
488 }
489
490 void mark_useful() {
491 _useless = false;
492 }
493
494 Node* uncommon_trap() const;
495
496 Node* Ideal(PhaseGVN* phase, bool can_reshape) {
497 return nullptr; // Don't optimize
498 }
499
500 const Type* Value(PhaseGVN* phase) const;
501 NOT_PRODUCT(void dump_spec(outputStream* st) const;)
502 };
503
504 class IfProjNode : public CProjNode {
505 public:
506 IfProjNode(IfNode *ifnode, uint idx) : CProjNode(ifnode,idx) {}
507 virtual Node* Identity(PhaseGVN* phase);
508
509 protected:
510 // Type of If input when this branch is always taken
511 virtual bool always_taken(const TypeTuple* t) const = 0;
512 };
513
514 class IfTrueNode : public IfProjNode {
515 public:
516 IfTrueNode( IfNode *ifnode ) : IfProjNode(ifnode,1) {
517 init_class_id(Class_IfTrue);
518 }
519 virtual int Opcode() const;
520
521 protected:
522 virtual bool always_taken(const TypeTuple* t) const { return t == TypeTuple::IFTRUE; }
523 };
524
525 class IfFalseNode : public IfProjNode {
526 public:
527 IfFalseNode( IfNode *ifnode ) : IfProjNode(ifnode,0) {
528 init_class_id(Class_IfFalse);
529 }
530 virtual int Opcode() const;
531
532 protected:
533 virtual bool always_taken(const TypeTuple* t) const { return t == TypeTuple::IFFALSE; }
534 };
535
536
537 //------------------------------PCTableNode------------------------------------
538 // Build an indirect branch table. Given a control and a table index,
539 // control is passed to the Projection matching the table index. Used to
540 // implement switch statements and exception-handling capabilities.
541 // Undefined behavior if passed-in index is not inside the table.
542 class PCTableNode : public MultiBranchNode {
543 virtual uint hash() const; // Target count; table size
544 virtual bool cmp( const Node &n ) const;
545 virtual uint size_of() const { return sizeof(*this); }
546
547 public:
548 const uint _size; // Number of targets
549
550 PCTableNode( Node *ctrl, Node *idx, uint size ) : MultiBranchNode(2), _size(size) {
551 init_class_id(Class_PCTable);
552 init_req(0, ctrl);
553 init_req(1, idx);
554 }
555 virtual int Opcode() const;
556 virtual const Type* Value(PhaseGVN* phase) const;
557 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
558 virtual const Type *bottom_type() const;
559 virtual bool pinned() const { return true; }
560 virtual int required_outcnt() const { return _size; }
561 };
562
563 //------------------------------JumpNode---------------------------------------
564 // Indirect branch. Uses PCTable above to implement a switch statement.
565 // It emits as a table load and local branch.
566 class JumpNode : public PCTableNode {
567 virtual uint size_of() const { return sizeof(*this); }
568 public:
569 float* _probs; // probability of each projection
570 float _fcnt; // total number of times this Jump was executed
571 JumpNode( Node* control, Node* switch_val, uint size, float* probs, float cnt)
572 : PCTableNode(control, switch_val, size),
573 _probs(probs), _fcnt(cnt) {
574 init_class_id(Class_Jump);
575 }
576 virtual int Opcode() const;
577 virtual const RegMask& out_RegMask() const;
578 virtual const Node* is_block_proj() const { return this; }
579 };
580
581 class JumpProjNode : public JProjNode {
582 virtual uint hash() const;
583 virtual bool cmp( const Node &n ) const;
584 virtual uint size_of() const { return sizeof(*this); }
585
586 private:
587 const int _dest_bci;
588 const uint _proj_no;
589 const int _switch_val;
590 public:
591 JumpProjNode(Node* jumpnode, uint proj_no, int dest_bci, int switch_val)
592 : JProjNode(jumpnode, proj_no), _dest_bci(dest_bci), _proj_no(proj_no), _switch_val(switch_val) {
593 init_class_id(Class_JumpProj);
594 }
595
596 virtual int Opcode() const;
597 virtual const Type* bottom_type() const { return Type::CONTROL; }
598 int dest_bci() const { return _dest_bci; }
599 int switch_val() const { return _switch_val; }
600 uint proj_no() const { return _proj_no; }
601 #ifndef PRODUCT
602 virtual void dump_spec(outputStream *st) const;
603 virtual void dump_compact_spec(outputStream *st) const;
604 #endif
605 };
606
607 //------------------------------CatchNode--------------------------------------
608 // Helper node to fork exceptions. "Catch" catches any exceptions thrown by
609 // a just-prior call. Looks like a PCTableNode but emits no code - just the
610 // table. The table lookup and branch is implemented by RethrowNode.
611 class CatchNode : public PCTableNode {
612 public:
613 CatchNode( Node *ctrl, Node *idx, uint size ) : PCTableNode(ctrl,idx,size){
614 init_class_id(Class_Catch);
615 }
616 virtual int Opcode() const;
617 virtual const Type* Value(PhaseGVN* phase) const;
618 };
619
620 // CatchProjNode controls which exception handler is targeted after a call.
621 // It is passed in the bci of the target handler, or no_handler_bci in case
622 // the projection doesn't lead to an exception handler.
623 class CatchProjNode : public CProjNode {
624 virtual uint hash() const;
625 virtual bool cmp( const Node &n ) const;
626 virtual uint size_of() const { return sizeof(*this); }
627
628 private:
629 const int _handler_bci;
630
631 public:
632 enum {
633 fall_through_index = 0, // the fall through projection index
634 catch_all_index = 1, // the projection index for catch-alls
635 no_handler_bci = -1 // the bci for fall through or catch-all projs
636 };
637
638 CatchProjNode(Node* catchnode, uint proj_no, int handler_bci)
639 : CProjNode(catchnode, proj_no), _handler_bci(handler_bci) {
640 init_class_id(Class_CatchProj);
641 assert(proj_no != fall_through_index || handler_bci < 0, "fall through case must have bci < 0");
642 }
643
644 virtual int Opcode() const;
645 virtual Node* Identity(PhaseGVN* phase);
646 virtual const Type *bottom_type() const { return Type::CONTROL; }
647 int handler_bci() const { return _handler_bci; }
648 bool is_handler_proj() const { return _handler_bci >= 0; }
649 #ifndef PRODUCT
650 virtual void dump_spec(outputStream *st) const;
651 #endif
652 };
653
654
655 //---------------------------------CreateExNode--------------------------------
656 // Helper node to create the exception coming back from a call
657 class CreateExNode : public TypeNode {
658 public:
659 CreateExNode(const Type* t, Node* control, Node* i_o) : TypeNode(t, 2) {
660 init_req(0, control);
661 init_req(1, i_o);
662 }
663 virtual int Opcode() const;
664 virtual Node* Identity(PhaseGVN* phase);
665 virtual bool pinned() const { return true; }
666 uint match_edge(uint idx) const { return 0; }
667 virtual uint ideal_reg() const { return Op_RegP; }
668 };
669
670 //------------------------------NeverBranchNode-------------------------------
671 // The never-taken branch. Used to give the appearance of exiting infinite
672 // loops to those algorithms that like all paths to be reachable. Encodes
673 // empty.
674 class NeverBranchNode : public MultiBranchNode {
675 public:
676 NeverBranchNode(Node* ctrl) : MultiBranchNode(1) {
677 init_req(0, ctrl);
678 init_class_id(Class_NeverBranch);
679 }
680 virtual int Opcode() const;
681 virtual bool pinned() const { return true; };
682 virtual const Type *bottom_type() const { return TypeTuple::IFBOTH; }
683 virtual const Type* Value(PhaseGVN* phase) const;
684 virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
685 virtual int required_outcnt() const { return 2; }
686 virtual void emit(CodeBuffer &cbuf, PhaseRegAlloc *ra_) const { }
687 virtual uint size(PhaseRegAlloc *ra_) const { return 0; }
688 #ifndef PRODUCT
689 virtual void format( PhaseRegAlloc *, outputStream *st ) const;
690 #endif
691 };
692
693 //------------------------------BlackholeNode----------------------------
694 // Blackhole all arguments. This node would survive through the compiler
695 // the effects on its arguments, and would be finally matched to nothing.
696 class BlackholeNode : public MultiNode {
697 public:
698 BlackholeNode(Node* ctrl) : MultiNode(1) {
699 init_req(TypeFunc::Control, ctrl);
700 init_class_id(Class_Blackhole);
701 }
702 virtual int Opcode() const;
703 virtual uint ideal_reg() const { return 0; } // not matched in the AD file
704 virtual const Type* bottom_type() const { return TypeTuple::MEMBAR; }
705
706 const RegMask &in_RegMask(uint idx) const {
707 // Fake the incoming arguments mask for blackholes: accept all registers
708 // and all stack slots. This would avoid any redundant register moves
709 // for blackhole inputs.
710 return RegMask::All;
711 }
712 #ifndef PRODUCT
713 virtual void format(PhaseRegAlloc* ra, outputStream* st) const;
714 #endif
715 };
716
717
718 #endif // SHARE_OPTO_CFGNODE_HPP