1 /*
2 * Copyright (c) 1997, 2015, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
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
21 * questions.
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23 */
24
25 #ifndef SHARE_VM_OOPS_GENERATEOOPMAP_HPP
26 #define SHARE_VM_OOPS_GENERATEOOPMAP_HPP
27
28 #include "interpreter/bytecodeStream.hpp"
29 #include "memory/allocation.inline.hpp"
30 #include "memory/universe.inline.hpp"
31 #include "oops/method.hpp"
32 #include "oops/oopsHierarchy.hpp"
33 #include "runtime/signature.hpp"
34
35 // Forward definition
36 class GenerateOopMap;
37 class BasicBlock;
38 class CellTypeState;
39 class StackMap;
40
41 // These two should be removed. But requires som code to be cleaned up
42 #define MAXARGSIZE 256 // This should be enough
43 #define MAX_LOCAL_VARS 65536 // 16-bit entry
44
45 typedef void (*jmpFct_t)(GenerateOopMap *c, int bcpDelta, int* data);
46
47
48 // RetTable
49 //
50 // Contains maping between jsr targets and there return addresses. One-to-many mapping
51 //
52 class RetTableEntry : public ResourceObj {
53 private:
54 static int _init_nof_jsrs; // Default size of jsrs list
55 int _target_bci; // Target PC address of jump (bytecode index)
56 GrowableArray<intptr_t> * _jsrs; // List of return addresses (bytecode index)
57 RetTableEntry *_next; // Link to next entry
58 public:
59 RetTableEntry(int target, RetTableEntry *next) { _target_bci=target; _jsrs = new GrowableArray<intptr_t>(_init_nof_jsrs); _next = next; }
60
61 // Query
62 int target_bci() const { return _target_bci; }
63 int nof_jsrs() const { return _jsrs->length(); }
64 int jsrs(int i) const { assert(i>=0 && i<nof_jsrs(), "Index out of bounds"); return _jsrs->at(i); }
65
66 // Update entry
67 void add_jsr (int return_bci) { _jsrs->append(return_bci); }
68 void add_delta (int bci, int delta);
69 RetTableEntry * next() const { return _next; }
70 };
71
72
73 class RetTable VALUE_OBJ_CLASS_SPEC {
74 private:
75 RetTableEntry *_first;
76 static int _init_nof_entries;
77
78 void add_jsr(int return_bci, int target_bci); // Adds entry to list
79 public:
80 RetTable() { _first = NULL; }
81 void compute_ret_table(const methodHandle& method);
82 void update_ret_table(int bci, int delta);
83 RetTableEntry* find_jsrs_for_target(int targBci);
84 };
85
86 //
87 // CellTypeState
88 //
89 class CellTypeState VALUE_OBJ_CLASS_SPEC {
90 private:
91 unsigned int _state;
92
93 // Masks for separating the BITS and INFO portions of a CellTypeState
94 enum { info_mask = right_n_bits(27),
95 bits_mask = (int)(~info_mask) };
96
97 // These constant are used for manipulating the BITS portion of a
98 // CellTypeState
99 enum { uninit_bit = (int)(nth_bit(31)),
100 ref_bit = nth_bit(30),
101 val_bit = nth_bit(29),
102 addr_bit = nth_bit(28),
103 valuetype_bit = nth_bit(27),
104 live_bits_mask = (int)(bits_mask & ~uninit_bit) };
105
106 // These constants are used for manipulating the INFO portion of a
107 // CellTypeState
108 enum { top_info_bit = nth_bit(26),
109 not_bottom_info_bit = nth_bit(25),
110 info_data_mask = right_n_bits(25),
111 info_conflict = info_mask };
112
113 // Within the INFO data, these values are used to distinguish different
114 // kinds of references.
115 enum { ref_not_lock_bit = nth_bit(24), // 0 if this reference is locked as a monitor
116 ref_slot_bit = nth_bit(23), // 1 if this reference is a "slot" reference,
117 // 0 if it is a "line" reference.
118 ref_data_mask = right_n_bits(23) };
119
120 // Within the INFO data, these values are used to distinguish different
121 // kinds of value types.
122 enum { valuetype_slot_bit = nth_bit(24), // 1 if this reference is a "slot" value type,
123 // 0 if it is a "line" value type.
124 valuetype_data_mask = right_n_bits(24) };
125
126 // These values are used to initialize commonly used CellTypeState
127 // constants.
128 enum { bottom_value = 0,
129 uninit_value = (int)(uninit_bit | info_conflict),
130 ref_value = ref_bit,
131 ref_conflict = ref_bit | info_conflict,
132 val_value = val_bit | info_conflict,
133 valuetype_conflict = valuetype_bit | info_conflict,
134 addr_value = addr_bit,
135 addr_conflict = addr_bit | info_conflict };
136
137 public:
138
139 // Since some C++ constructors generate poor code for declarations of the
140 // form...
141 //
142 // CellTypeState vector[length];
143 //
144 // ...we avoid making a constructor for this class. CellTypeState values
145 // should be constructed using one of the make_* methods:
146
147 static CellTypeState make_any(int state) {
148 CellTypeState s;
149 s._state = state;
150 // Causes SS10 warning.
151 // assert(s.is_valid_state(), "check to see if CellTypeState is valid");
152 return s;
153 }
154
155 static CellTypeState make_bottom() {
156 return make_any(0);
157 }
158
159 static CellTypeState make_top() {
160 return make_any(AllBits);
161 }
162
163 static CellTypeState make_addr(int bci) {
164 assert((bci >= 0) && (bci < info_data_mask), "check to see if ret addr is valid");
165 return make_any(addr_bit | not_bottom_info_bit | (bci & info_data_mask));
166 }
167
168 static CellTypeState make_slot_ref(int slot_num) {
169 assert(slot_num >= 0 && slot_num < ref_data_mask, "slot out of range");
170 return make_any(ref_bit | not_bottom_info_bit | ref_not_lock_bit | ref_slot_bit |
171 (slot_num & ref_data_mask));
172 }
173
174 static CellTypeState make_line_ref(int bci) {
175 assert(bci >= 0 && bci < ref_data_mask, "line out of range");
176 return make_any(ref_bit | not_bottom_info_bit | ref_not_lock_bit |
177 (bci & ref_data_mask));
178 }
179
180 static CellTypeState make_lock_ref(int bci) {
181 assert(bci >= 0 && bci < ref_data_mask, "line out of range");
182 return make_any(ref_bit | not_bottom_info_bit | (bci & ref_data_mask));
183 }
184
185 static CellTypeState make_slot_valuetype(int slot_num) {
186 assert(slot_num >= 0 && slot_num < valuetype_data_mask, "slot out of range");
187 return make_any(valuetype_bit | not_bottom_info_bit | valuetype_slot_bit |
188 (slot_num & valuetype_data_mask));
189 }
190
191 static CellTypeState make_line_valuetype(int bci) {
192 assert(bci >= 0 && bci < valuetype_data_mask, "line out of range");
193 return make_any(valuetype_bit | not_bottom_info_bit |
194 (bci & valuetype_data_mask));
195 }
196
197 // Query methods:
198 bool is_bottom() const { return _state == 0; }
199 bool is_live() const { return ((_state & live_bits_mask) != 0); }
200 bool is_valid_state() const {
201 // Uninitialized and value cells must contain no data in their info field:
202 if ((can_be_uninit() || can_be_value()) && !is_info_top()) {
203 return false;
204 }
205 // The top bit is only set when all info bits are set:
206 if (is_info_top() && ((_state & info_mask) != info_mask)) {
207 return false;
208 }
209 // The not_bottom_bit must be set when any other info bit is set:
210 if (is_info_bottom() && ((_state & info_mask) != 0)) {
211 return false;
212 }
213 return true;
214 }
215
216 bool is_address() const { return ((_state & bits_mask) == addr_bit); }
217 bool is_reference() const { return ((_state & bits_mask) == ref_bit); }
218 bool is_value() const { return ((_state & bits_mask) == val_bit); }
219 bool is_valuetype() const { return ((_state & bits_mask) == valuetype_bit); }
220 bool is_uninit() const { return ((_state & bits_mask) == (uint)uninit_bit); }
221
222 bool can_be_address() const { return ((_state & addr_bit) != 0); }
223 bool can_be_reference() const { return ((_state & ref_bit) != 0); }
224 bool can_be_value() const { return ((_state & val_bit) != 0); }
225 bool can_be_valuetype() const { return ((_state & valuetype_bit) != 0); }
226 bool can_be_uninit() const { return ((_state & uninit_bit) != 0); }
227
228 bool is_info_bottom() const { return ((_state & not_bottom_info_bit) == 0); }
229 bool is_info_top() const { return ((_state & top_info_bit) != 0); }
230 int get_info() const {
231 assert((!is_info_top() && !is_info_bottom()),
232 "check to make sure top/bottom info is not used");
233 return (_state & info_data_mask);
234 }
235
236 bool is_good_address() const { return is_address() && !is_info_top(); }
237 bool is_lock_reference() const {
238 return ((_state & (bits_mask | top_info_bit | ref_not_lock_bit)) == ref_bit);
239 }
240 bool is_nonlock_reference() const {
241 return ((_state & (bits_mask | top_info_bit | ref_not_lock_bit)) == (ref_bit | ref_not_lock_bit));
242 }
243
244 bool equal(CellTypeState a) const { return _state == a._state; }
245 bool equal_kind(CellTypeState a) const {
246 return (_state & bits_mask) == (a._state & bits_mask);
247 }
248
249 char to_char() const;
250
251 // Merge
252 CellTypeState merge (CellTypeState cts, int slot) const;
253
254 // Debugging output
255 void print(outputStream *os);
256
257 // Default values of common values
258 static CellTypeState bottom;
259 static CellTypeState uninit;
260 static CellTypeState ref;
261 static CellTypeState value;
262 static CellTypeState valuetype;
263 static CellTypeState refUninit;
264 static CellTypeState varUninit;
265 static CellTypeState top;
266 static CellTypeState addr;
267 };
268
269
270 //
271 // BasicBlockStruct
272 //
273 class BasicBlock: ResourceObj {
274 private:
275 bool _changed; // Reached a fixpoint or not
276 public:
277 enum Constants {
278 _dead_basic_block = -2,
279 _unreached = -1 // Alive but not yet reached by analysis
280 // >=0 // Alive and has a merged state
281 };
282
283 int _bci; // Start of basic block
284 int _end_bci; // Bci of last instruction in basicblock
285 int _max_locals; // Determines split between vars and stack
286 int _max_stack; // Determines split between stack and monitors
287 CellTypeState* _state; // State (vars, stack) at entry.
288 int _stack_top; // -1 indicates bottom stack value.
289 int _monitor_top; // -1 indicates bottom monitor stack value.
290
291 CellTypeState* vars() { return _state; }
292 CellTypeState* stack() { return _state + _max_locals; }
293
294 bool changed() { return _changed; }
295 void set_changed(bool s) { _changed = s; }
296
297 bool is_reachable() const { return _stack_top >= 0; } // Analysis has reached this basicblock
298
299 // All basicblocks that are unreachable are going to have a _stack_top == _dead_basic_block.
300 // This info. is setup in a pre-parse before the real abstract interpretation starts.
301 bool is_dead() const { return _stack_top == _dead_basic_block; }
302 bool is_alive() const { return _stack_top != _dead_basic_block; }
303 void mark_as_alive() { assert(is_dead(), "must be dead"); _stack_top = _unreached; }
304 };
305
306
307 //
308 // GenerateOopMap
309 //
310 // Main class used to compute the pointer-maps in a Method
311 //
312 class GenerateOopMap VALUE_OBJ_CLASS_SPEC {
313 protected:
314
315 // _monitor_top is set to this constant to indicate that a monitor matching
316 // problem was encountered prior to this point in control flow.
317 enum { bad_monitors = -1 };
318
319 // Main variables
320 methodHandle _method; // The method we are examine
321 RetTable _rt; // Contains the return address mappings
322 int _max_locals; // Cached value of no. of locals
323 int _max_stack; // Cached value of max. stack depth
324 int _max_monitors; // Cached value of max. monitor stack depth
325 int _has_exceptions; // True, if exceptions exist for method
326 bool _got_error; // True, if an error occurred during interpretation.
327 Handle _exception; // Exception if got_error is true.
328 bool _did_rewriting; // was bytecodes rewritten
329 bool _did_relocation; // was relocation neccessary
330 bool _monitor_safe; // The monitors in this method have been determined
331 // to be safe.
332
333 // Working Cell type state
334 int _state_len; // Size of states
335 CellTypeState *_state; // list of states
336 char *_state_vec_buf; // Buffer used to print a readable version of a state
337 int _stack_top;
338 int _monitor_top;
339
340 // Timing and statistics
341 static elapsedTimer _total_oopmap_time; // Holds cumulative oopmap generation time
342 static long _total_byte_count; // Holds cumulative number of bytes inspected
343
344 // Cell type methods
345 void init_state();
346 void make_context_uninitialized ();
347 int methodsig_to_effect (Symbol* signature, bool isStatic, CellTypeState* effect);
348 bool merge_local_state_vectors (CellTypeState* cts, CellTypeState* bbts);
349 bool merge_monitor_state_vectors(CellTypeState* cts, CellTypeState* bbts);
350 void copy_state (CellTypeState *dst, CellTypeState *src);
351 void merge_state_into_bb (BasicBlock *bb);
352 static void merge_state (GenerateOopMap *gom, int bcidelta, int* data);
353 void set_var (int localNo, CellTypeState cts);
354 CellTypeState get_var (int localNo);
355 CellTypeState pop ();
356 void push (CellTypeState cts);
357 CellTypeState monitor_pop ();
358 void monitor_push (CellTypeState cts);
359 CellTypeState * vars () { return _state; }
360 CellTypeState * stack () { return _state+_max_locals; }
361 CellTypeState * monitors () { return _state+_max_locals+_max_stack; }
362
363 void replace_all_CTS_matches (CellTypeState match,
364 CellTypeState replace);
365 void print_states (outputStream *os, CellTypeState *vector, int num);
366 void print_current_state (outputStream *os,
367 BytecodeStream *itr,
368 bool detailed);
369 void report_monitor_mismatch (const char *msg);
370
371 // Basicblock info
372 BasicBlock * _basic_blocks; // Array of basicblock info
373 int _gc_points;
374 int _bb_count;
375 BitMap _bb_hdr_bits;
376
377 // Basicblocks methods
378 void initialize_bb ();
379 void mark_bbheaders_and_count_gc_points();
380 bool is_bb_header (int bci) const {
381 return _bb_hdr_bits.at(bci);
382 }
383 int gc_points () const { return _gc_points; }
384 int bb_count () const { return _bb_count; }
385 void set_bbmark_bit (int bci) {
386 _bb_hdr_bits.at_put(bci, true);
387 }
388 void clear_bbmark_bit (int bci) {
389 _bb_hdr_bits.at_put(bci, false);
390 }
391 BasicBlock * get_basic_block_at (int bci) const;
392 BasicBlock * get_basic_block_containing (int bci) const;
393 void interp_bb (BasicBlock *bb);
394 void restore_state (BasicBlock *bb);
395 int next_bb_start_pc (BasicBlock *bb);
396 void update_basic_blocks (int bci, int delta, int new_method_size);
397 static void bb_mark_fct (GenerateOopMap *c, int deltaBci, int *data);
398
399 // Dead code detection
400 void mark_reachable_code();
401 static void reachable_basicblock (GenerateOopMap *c, int deltaBci, int *data);
402
403 // Interpretation methods (primary)
404 void do_interpretation ();
405 void init_basic_blocks ();
406 void setup_method_entry_state ();
407 void interp_all ();
408
409 // Interpretation methods (secondary)
410 void interp1 (BytecodeStream *itr);
411 void do_exception_edge (BytecodeStream *itr);
412 void check_type (CellTypeState expected, CellTypeState actual);
413 void ppstore (CellTypeState *in, int loc_no);
414 void ppload (CellTypeState *out, int loc_no);
415 void ppush1 (CellTypeState in);
416 void ppush (CellTypeState *in);
417 void ppop1 (CellTypeState out);
418 void ppop (CellTypeState *out);
419 void ppop_any (int poplen);
420 void pp (CellTypeState *in, CellTypeState *out);
421 void pp_new_ref (CellTypeState *in, int bci);
422 void pp_new_valuetype (CellTypeState *in, int bci);
423 void ppdupswap (int poplen, const char *out);
424 void do_ldc (int bci);
425 void do_astore (int idx);
426 void do_vstore (int idx);
427 void do_jsr (int delta);
428 void do_field (int is_get, int is_static, int is_valuetype, int idx, int bci);
429 void do_method (int is_static, int is_value, int idx, int bci);
430 void do_vnew (int idx, int bci);
431 void do_vwithfield (int idx, int bci);
432 void do_multianewarray (int dims, int bci);
433 void do_monitorenter (int bci);
434 void do_monitorexit (int bci);
435 void do_return_monitor_check ();
436 void do_checkcast ();
437 CellTypeState *sigchar_to_effect (char sigch, int bci, CellTypeState *out);
438 int copy_cts (CellTypeState *dst, CellTypeState *src);
439
440 // Error handling
441 void error_work (const char *format, va_list ap) ATTRIBUTE_PRINTF(2, 0);
442 void report_error (const char *format, ...) ATTRIBUTE_PRINTF(2, 3);
443 void verify_error (const char *format, ...) ATTRIBUTE_PRINTF(2, 3);
444 bool got_error() { return _got_error; }
445
446 // Create result set
447 bool _report_result;
448 bool _report_result_for_send; // Unfortunatly, stackmaps for sends are special, so we need some extra
449 BytecodeStream *_itr_send; // variables to handle them properly.
450
451 void report_result ();
452
453 // Initvars
454 GrowableArray<intptr_t> * _init_vars;
455
456 void initialize_vars ();
457 void add_to_ref_init_set (int localNo);
458
459 // Conflicts rewrite logic
460 bool _conflict; // True, if a conflict occurred during interpretation
461 int _nof_refval_conflicts; // No. of conflicts that require rewrites
462 int * _new_var_map;
463
464 void record_refval_conflict (int varNo);
465 void rewrite_refval_conflicts ();
466 void rewrite_refval_conflict (int from, int to);
467 bool rewrite_refval_conflict_inst (BytecodeStream *i, int from, int to);
468 bool rewrite_load_or_store (BytecodeStream *i, Bytecodes::Code bc, Bytecodes::Code bc0, unsigned int varNo);
469
470 void expand_current_instr (int bci, int ilen, int newIlen, u_char inst_buffer[]);
471 bool is_astore (BytecodeStream *itr, int *index);
472 bool is_aload (BytecodeStream *itr, int *index);
473
474 // List of bci's where a return address is on top of the stack
475 GrowableArray<intptr_t> *_ret_adr_tos;
476
477 bool stack_top_holds_ret_addr (int bci);
478 void compute_ret_adr_at_TOS ();
479 void update_ret_adr_at_TOS (int bci, int delta);
480
481 int binsToHold (int no) { return ((no+(BitsPerWord-1))/BitsPerWord); }
482 char *state_vec_to_string (CellTypeState* vec, int len);
483
484 // Helper method. Can be used in subclasses to fx. calculate gc_points. If the current instuction
485 // is a control transfer, then calls the jmpFct all possible destinations.
486 void ret_jump_targets_do (BytecodeStream *bcs, jmpFct_t jmpFct, int varNo,int *data);
487 bool jump_targets_do (BytecodeStream *bcs, jmpFct_t jmpFct, int *data);
488
489 friend class RelocCallback;
490 public:
491 GenerateOopMap(const methodHandle& method);
492
493 // Compute the map.
494 void compute_map(TRAPS);
495 void result_for_basicblock(int bci); // Do a callback on fill_stackmap_for_opcodes for basicblock containing bci
496
497 // Query
498 int max_locals() const { return _max_locals; }
499 Method* method() const { return _method(); }
500 methodHandle method_as_handle() const { return _method; }
501
502 bool did_rewriting() { return _did_rewriting; }
503 bool did_relocation() { return _did_relocation; }
504
505 static void print_time();
506
507 // Monitor query
508 bool monitor_safe() { return _monitor_safe; }
509
510 // Specialization methods. Intended use:
511 // - possible_gc_point must return true for every bci for which the stackmaps must be returned
512 // - fill_stackmap_prolog is called just before the result is reported. The arguments tells the estimated
513 // number of gc points
514 // - fill_stackmap_for_opcodes is called once for each bytecode index in order (0...code_length-1)
515 // - fill_stackmap_epilog is called after all results has been reported. Note: Since the algorithm does not report
516 // stackmaps for deadcode, fewer gc_points might have been encounted than assumed during the epilog. It is the
517 // responsibility of the subclass to count the correct number.
518 // - fill_init_vars are called once with the result of the init_vars computation
519 //
520 // All these methods are used during a call to: compute_map. Note: Non of the return results are valid
521 // after compute_map returns, since all values are allocated as resource objects.
522 //
523 // All virtual method must be implemented in subclasses
524 virtual bool allow_rewrites () const { return false; }
525 virtual bool report_results () const { return true; }
526 virtual bool report_init_vars () const { return true; }
527 virtual bool possible_gc_point (BytecodeStream *bcs) { ShouldNotReachHere(); return false; }
528 virtual void fill_stackmap_prolog (int nof_gc_points) { ShouldNotReachHere(); }
529 virtual void fill_stackmap_epilog () { ShouldNotReachHere(); }
530 virtual void fill_stackmap_for_opcodes (BytecodeStream *bcs,
531 CellTypeState* vars,
532 CellTypeState* stack,
533 int stackTop) { ShouldNotReachHere(); }
534 virtual void fill_init_vars (GrowableArray<intptr_t> *init_vars) { ShouldNotReachHere();; }
535 };
536
537 //
538 // Subclass of the GenerateOopMap Class that just do rewrites of the method, if needed.
539 // It does not store any oopmaps.
540 //
541 class ResolveOopMapConflicts: public GenerateOopMap {
542 private:
543
544 bool _must_clear_locals;
545
546 virtual bool report_results() const { return false; }
547 virtual bool report_init_vars() const { return true; }
548 virtual bool allow_rewrites() const { return true; }
549 virtual bool possible_gc_point (BytecodeStream *bcs) { return false; }
550 virtual void fill_stackmap_prolog (int nof_gc_points) {}
551 virtual void fill_stackmap_epilog () {}
552 virtual void fill_stackmap_for_opcodes (BytecodeStream *bcs,
553 CellTypeState* vars,
554 CellTypeState* stack,
555 int stack_top) {}
556 virtual void fill_init_vars (GrowableArray<intptr_t> *init_vars) { _must_clear_locals = init_vars->length() > 0; }
557
558 #ifndef PRODUCT
559 // Statistics
560 static int _nof_invocations;
561 static int _nof_rewrites;
562 static int _nof_relocations;
563 #endif
564
565 public:
566 ResolveOopMapConflicts(const methodHandle& method) : GenerateOopMap(method) { _must_clear_locals = false; };
567
568 methodHandle do_potential_rewrite(TRAPS);
569 bool must_clear_locals() const { return _must_clear_locals; }
570 };
571
572
573 //
574 // Subclass used by the compiler to generate pairing infomation
575 //
576 class GeneratePairingInfo: public GenerateOopMap {
577 private:
578
579 virtual bool report_results() const { return false; }
580 virtual bool report_init_vars() const { return false; }
581 virtual bool allow_rewrites() const { return false; }
582 virtual bool possible_gc_point (BytecodeStream *bcs) { return false; }
583 virtual void fill_stackmap_prolog (int nof_gc_points) {}
584 virtual void fill_stackmap_epilog () {}
585 virtual void fill_stackmap_for_opcodes (BytecodeStream *bcs,
586 CellTypeState* vars,
587 CellTypeState* stack,
588 int stack_top) {}
589 virtual void fill_init_vars (GrowableArray<intptr_t> *init_vars) {}
590 public:
591 GeneratePairingInfo(const methodHandle& method) : GenerateOopMap(method) {};
592
593 // Call compute_map(CHECK) to generate info.
594 };
595
596 #endif // SHARE_VM_OOPS_GENERATEOOPMAP_HPP