1 #ifdef USE_PRAGMA_IDENT_HDR
2 #pragma ident "@(#)generateOopMap.hpp 1.65 07/05/05 17:06:01 JVM"
3 #endif
4 /*
5 * Copyright 1997-2005 Sun Microsystems, Inc. All Rights Reserved.
6 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
7 *
8 * This code is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License version 2 only, as
10 * published by the Free Software Foundation.
11 *
12 * This code is distributed in the hope that it will be useful, but WITHOUT
13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 * version 2 for more details (a copy is included in the LICENSE file that
16 * accompanied this code).
17 *
18 * You should have received a copy of the GNU General Public License version
19 * 2 along with this work; if not, write to the Free Software Foundation,
20 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
21 *
22 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
23 * CA 95054 USA or visit www.sun.com if you need additional information or
24 * have any questions.
25 *
26 */
27
28 // Forward definition
29 class MethodOopMap;
30 class GenerateOopMap;
31 class BasicBlock;
32 class CellTypeState;
33 class StackMap;
34
35 // These two should be removed. But requires som code to be cleaned up
36 #define MAXARGSIZE 256 // This should be enough
37 #define MAX_LOCAL_VARS 65536 // 16-bit entry
38
39 typedef void (*jmpFct_t)(GenerateOopMap *c, int bcpDelta, int* data);
40
41
42 // RetTable
43 //
44 // Contains maping between jsr targets and there return addresses. One-to-many mapping
45 //
46 class RetTableEntry : public ResourceObj {
47 private:
48 static int _init_nof_jsrs; // Default size of jsrs list
49 int _target_bci; // Target PC address of jump (bytecode index)
50 GrowableArray<intptr_t> * _jsrs; // List of return addresses (bytecode index)
51 RetTableEntry *_next; // Link to next entry
52 public:
53 RetTableEntry(int target, RetTableEntry *next) { _target_bci=target; _jsrs = new GrowableArray<intptr_t>(_init_nof_jsrs); _next = next; }
54
55 // Query
56 int target_bci() const { return _target_bci; }
57 int nof_jsrs() const { return _jsrs->length(); }
58 int jsrs(int i) const { assert(i>=0 && i<nof_jsrs(), "Index out of bounds"); return _jsrs->at(i); }
59
60 // Update entry
61 void add_jsr (int return_bci) { _jsrs->append(return_bci); }
62 void add_delta (int bci, int delta);
63 RetTableEntry * next() const { return _next; }
64 };
65
66
67 class RetTable VALUE_OBJ_CLASS_SPEC {
68 private:
69 RetTableEntry *_first;
70 static int _init_nof_entries;
71
72 void add_jsr(int return_bci, int target_bci); // Adds entry to list
73 public:
74 RetTable() { _first = NULL; }
75 void compute_ret_table(methodHandle method);
76 void update_ret_table(int bci, int delta);
77 RetTableEntry* find_jsrs_for_target(int targBci);
78 };
79
80 //
81 // CellTypeState
82 //
83 class CellTypeState VALUE_OBJ_CLASS_SPEC {
84 private:
85 unsigned int _state;
86
87 // Masks for separating the BITS and INFO portions of a CellTypeState
88 enum { info_mask = right_n_bits(28),
89 bits_mask = (int)(~info_mask) };
90
91 // These constant are used for manipulating the BITS portion of a
92 // CellTypeState
93 enum { uninit_bit = (int)(nth_bit(31)),
94 ref_bit = nth_bit(30),
95 val_bit = nth_bit(29),
96 addr_bit = nth_bit(28),
97 live_bits_mask = (int)(bits_mask & ~uninit_bit) };
98
99 // These constants are used for manipulating the INFO portion of a
100 // CellTypeState
101 enum { top_info_bit = nth_bit(27),
102 not_bottom_info_bit = nth_bit(26),
103 info_data_mask = right_n_bits(26),
104 info_conflict = info_mask };
105
106 // Within the INFO data, these values are used to distinguish different
107 // kinds of references.
108 enum { ref_not_lock_bit = nth_bit(25), // 0 if this reference is locked as a monitor
109 ref_slot_bit = nth_bit(24), // 1 if this reference is a "slot" reference,
110 // 0 if it is a "line" reference.
111 ref_data_mask = right_n_bits(24) };
112
113
114 // These values are used to initialize commonly used CellTypeState
115 // constants.
116 enum { bottom_value = 0,
117 uninit_value = (int)(uninit_bit | info_conflict),
118 ref_value = ref_bit,
119 ref_conflict = ref_bit | info_conflict,
120 val_value = val_bit | info_conflict,
121 addr_value = addr_bit,
122 addr_conflict = addr_bit | info_conflict };
123
124 public:
125
126 // Since some C++ constructors generate poor code for declarations of the
127 // form...
128 //
129 // CellTypeState vector[length];
130 //
131 // ...we avoid making a constructor for this class. CellTypeState values
132 // should be constructed using one of the make_* methods:
133
134 static CellTypeState make_any(int state) {
135 CellTypeState s;
136 s._state = state;
137 // Causes SS10 warning.
138 // assert(s.is_valid_state(), "check to see if CellTypeState is valid");
139 return s;
140 }
141
142 static CellTypeState make_bottom() {
143 return make_any(0);
144 }
145
146 static CellTypeState make_top() {
147 return make_any(AllBits);
148 }
149
150 static CellTypeState make_addr(int bci) {
151 assert((bci >= 0) && (bci < info_data_mask), "check to see if ret addr is valid");
152 return make_any(addr_bit | not_bottom_info_bit | (bci & info_data_mask));
153 }
154
155 static CellTypeState make_slot_ref(int slot_num) {
156 assert(slot_num >= 0 && slot_num < ref_data_mask, "slot out of range");
157 return make_any(ref_bit | not_bottom_info_bit | ref_not_lock_bit | ref_slot_bit |
158 (slot_num & ref_data_mask));
159 }
160
161 static CellTypeState make_line_ref(int bci) {
162 assert(bci >= 0 && bci < ref_data_mask, "line out of range");
163 return make_any(ref_bit | not_bottom_info_bit | ref_not_lock_bit |
164 (bci & ref_data_mask));
165 }
166
167 static CellTypeState make_lock_ref(int bci) {
168 assert(bci >= 0 && bci < ref_data_mask, "line out of range");
169 return make_any(ref_bit | not_bottom_info_bit | (bci & ref_data_mask));
170 }
171
172 // Query methods:
173 bool is_bottom() const { return _state == 0; }
174 bool is_live() const { return ((_state & live_bits_mask) != 0); }
175 bool is_valid_state() const {
176 // Uninitialized and value cells must contain no data in their info field:
177 if ((can_be_uninit() || can_be_value()) && !is_info_top()) {
178 return false;
179 }
180 // The top bit is only set when all info bits are set:
181 if (is_info_top() && ((_state & info_mask) != info_mask)) {
182 return false;
183 }
184 // The not_bottom_bit must be set when any other info bit is set:
185 if (is_info_bottom() && ((_state & info_mask) != 0)) {
186 return false;
187 }
188 return true;
189 }
190
191 bool is_address() const { return ((_state & bits_mask) == addr_bit); }
192 bool is_reference() const { return ((_state & bits_mask) == ref_bit); }
193 bool is_value() const { return ((_state & bits_mask) == val_bit); }
194 bool is_uninit() const { return ((_state & bits_mask) == (uint)uninit_bit); }
195
196 bool can_be_address() const { return ((_state & addr_bit) != 0); }
197 bool can_be_reference() const { return ((_state & ref_bit) != 0); }
198 bool can_be_value() const { return ((_state & val_bit) != 0); }
199 bool can_be_uninit() const { return ((_state & uninit_bit) != 0); }
200
201 bool is_info_bottom() const { return ((_state & not_bottom_info_bit) == 0); }
202 bool is_info_top() const { return ((_state & top_info_bit) != 0); }
203 int get_info() const {
204 assert((!is_info_top() && !is_info_bottom()),
205 "check to make sure top/bottom info is not used");
206 return (_state & info_data_mask);
207 }
208
209 bool is_good_address() const { return is_address() && !is_info_top(); }
210 bool is_lock_reference() const {
211 return ((_state & (bits_mask | top_info_bit | ref_not_lock_bit)) == ref_bit);
212 }
213 bool is_nonlock_reference() const {
214 return ((_state & (bits_mask | top_info_bit | ref_not_lock_bit)) == (ref_bit | ref_not_lock_bit));
215 }
216
217 bool equal(CellTypeState a) const { return _state == a._state; }
218 bool equal_kind(CellTypeState a) const {
219 return (_state & bits_mask) == (a._state & bits_mask);
220 }
221
222 char to_char() const;
223
224 // Merge
225 CellTypeState merge (CellTypeState cts, int slot) const;
226
227 // Debugging output
228 void print(outputStream *os);
229
230 // Default values of common values
231 static CellTypeState bottom;
232 static CellTypeState uninit;
233 static CellTypeState ref;
234 static CellTypeState value;
235 static CellTypeState refUninit;
236 static CellTypeState varUninit;
237 static CellTypeState top;
238 static CellTypeState addr;
239 };
240
241
242 //
243 // BasicBlockStruct
244 //
245 class BasicBlock: ResourceObj {
246 private:
247 bool _changed; // Reached a fixpoint or not
248 public:
249 enum Constants {
250 _dead_basic_block = -2,
251 _unreached = -1 // Alive but not yet reached by analysis
252 // >=0 // Alive and has a merged state
253 };
254
255 int _bci; // Start of basic block
256 int _end_bci; // Bci of last instruction in basicblock
257 int _max_locals; // Determines split between vars and stack
258 int _max_stack; // Determines split between stack and monitors
259 CellTypeState* _state; // State (vars, stack) at entry.
260 int _stack_top; // -1 indicates bottom stack value.
261 int _monitor_top; // -1 indicates bottom monitor stack value.
262
263 CellTypeState* vars() { return _state; }
264 CellTypeState* stack() { return _state + _max_locals; }
265
266 bool changed() { return _changed; }
267 void set_changed(bool s) { _changed = s; }
268
269 bool is_reachable() const { return _stack_top >= 0; } // Analysis has reached this basicblock
270
271 // All basicblocks that are unreachable are going to have a _stack_top == _dead_basic_block.
272 // This info. is setup in a pre-parse before the real abstract interpretation starts.
273 bool is_dead() const { return _stack_top == _dead_basic_block; }
274 bool is_alive() const { return _stack_top != _dead_basic_block; }
275 void mark_as_alive() { assert(is_dead(), "must be dead"); _stack_top = _unreached; }
276 };
277
278
279 //
280 // GenerateOopMap
281 //
282 // Main class used to compute the pointer-maps in a MethodOop
283 //
284 class GenerateOopMap VALUE_OBJ_CLASS_SPEC {
285 protected:
286
287 // _monitor_top is set to this constant to indicate that a monitor matching
288 // problem was encountered prior to this point in control flow.
289 enum { bad_monitors = -1 };
290
291 // Main variables
292 methodHandle _method; // The method we are examine
293 RetTable _rt; // Contains the return address mappings
294 int _max_locals; // Cached value of no. of locals
295 int _max_stack; // Cached value of max. stack depth
296 int _max_monitors; // Cached value of max. monitor stack depth
297 int _has_exceptions; // True, if exceptions exist for method
298 bool _got_error; // True, if an error occured during interpretation.
299 Handle _exception; // Exception if got_error is true.
300 bool _did_rewriting; // was bytecodes rewritten
301 bool _did_relocation; // was relocation neccessary
302 bool _monitor_safe; // The monitors in this method have been determined
303 // to be safe.
304
305 // Working Cell type state
306 int _state_len; // Size of states
307 CellTypeState *_state; // list of states
308 char *_state_vec_buf; // Buffer used to print a readable version of a state
309 int _stack_top;
310 int _monitor_top;
311
312 // Timing and statistics
313 static elapsedTimer _total_oopmap_time; // Holds cumulative oopmap generation time
314 static long _total_byte_count; // Holds cumulative number of bytes inspected
315
316 // Cell type methods
317 void init_state();
318 void make_context_uninitialized ();
319 int methodsig_to_effect (symbolOop signature, bool isStatic, CellTypeState* effect);
320 bool merge_local_state_vectors (CellTypeState* cts, CellTypeState* bbts);
321 bool merge_monitor_state_vectors(CellTypeState* cts, CellTypeState* bbts);
322 void copy_state (CellTypeState *dst, CellTypeState *src);
323 void merge_state_into_bb (BasicBlock *bb);
324 static void merge_state (GenerateOopMap *gom, int bcidelta, int* data);
325 void set_var (int localNo, CellTypeState cts);
326 CellTypeState get_var (int localNo);
327 CellTypeState pop ();
328 void push (CellTypeState cts);
329 CellTypeState monitor_pop ();
330 void monitor_push (CellTypeState cts);
331 CellTypeState * vars () { return _state; }
332 CellTypeState * stack () { return _state+_max_locals; }
333 CellTypeState * monitors () { return _state+_max_locals+_max_stack; }
334
335 void replace_all_CTS_matches (CellTypeState match,
336 CellTypeState replace);
337 void print_states (outputStream *os, CellTypeState *vector, int num);
338 void print_current_state (outputStream *os,
339 BytecodeStream *itr,
340 bool detailed);
341 void report_monitor_mismatch (const char *msg);
342
343 // Basicblock info
344 BasicBlock * _basic_blocks; // Array of basicblock info
345 int _gc_points;
346 int _bb_count;
347 uintptr_t * _bb_hdr_bits;
348
349 // Basicblocks methods
350 void initialize_bb ();
351 void mark_bbheaders_and_count_gc_points();
352 bool is_bb_header (int bci) const { return (_bb_hdr_bits[bci >> LogBitsPerWord] & ((uintptr_t)1 << (bci & (BitsPerWord-1)))) != 0; }
353 int gc_points () const { return _gc_points; }
354 int bb_count () const { return _bb_count; }
355 void set_bbmark_bit (int bci);
356 void clear_bbmark_bit (int bci);
357 BasicBlock * get_basic_block_at (int bci) const;
358 BasicBlock * get_basic_block_containing (int bci) const;
359 void interp_bb (BasicBlock *bb);
360 void restore_state (BasicBlock *bb);
361 int next_bb_start_pc (BasicBlock *bb);
362 void update_basic_blocks (int bci, int delta, int new_method_size);
363 static void bb_mark_fct (GenerateOopMap *c, int deltaBci, int *data);
364
365 // Dead code detection
366 void mark_reachable_code();
367 static void reachable_basicblock (GenerateOopMap *c, int deltaBci, int *data);
368
369 // Interpretation methods (primary)
370 void do_interpretation ();
371 void init_basic_blocks ();
372 void setup_method_entry_state ();
373 void interp_all ();
374
375 // Interpretation methods (secondary)
376 void interp1 (BytecodeStream *itr);
377 void do_exception_edge (BytecodeStream *itr);
378 void check_type (CellTypeState expected, CellTypeState actual);
379 void ppstore (CellTypeState *in, int loc_no);
380 void ppload (CellTypeState *out, int loc_no);
381 void ppush1 (CellTypeState in);
382 void ppush (CellTypeState *in);
383 void ppop1 (CellTypeState out);
384 void ppop (CellTypeState *out);
385 void ppop_any (int poplen);
386 void pp (CellTypeState *in, CellTypeState *out);
387 void pp_new_ref (CellTypeState *in, int bci);
388 void ppdupswap (int poplen, const char *out);
389 void do_ldc (int idx, int bci);
390 void do_astore (int idx);
391 void do_jsr (int delta);
392 void do_field (int is_get, int is_static, int idx, int bci);
393 void do_method (int is_static, int is_interface, int idx, int bci);
394 void do_multianewarray (int dims, int bci);
395 void do_monitorenter (int bci);
396 void do_monitorexit (int bci);
397 void do_return_monitor_check ();
398 void do_checkcast ();
399 CellTypeState *sigchar_to_effect (char sigch, int bci, CellTypeState *out);
400 int copy_cts (CellTypeState *dst, CellTypeState *src);
401
402 // Error handling
403 void error_work (const char *format, va_list ap);
404 void report_error (const char *format, ...);
405 void verify_error (const char *format, ...);
406 bool got_error() { return _got_error; }
407
408 // Create result set
409 bool _report_result;
410 bool _report_result_for_send; // Unfortunatly, stackmaps for sends are special, so we need some extra
411 BytecodeStream *_itr_send; // variables to handle them properly.
412
413 void report_result ();
414
415 // Initvars
416 GrowableArray<intptr_t> * _init_vars;
417
418 void initialize_vars ();
419 void add_to_ref_init_set (int localNo);
420
421 // Conflicts rewrite logic
422 bool _conflict; // True, if a conflict occured during interpretation
423 int _nof_refval_conflicts; // No. of conflicts that require rewrites
424 int * _new_var_map;
425
426 void record_refval_conflict (int varNo);
427 void rewrite_refval_conflicts ();
428 void rewrite_refval_conflict (int from, int to);
429 bool rewrite_refval_conflict_inst (BytecodeStream *i, int from, int to);
430 bool rewrite_load_or_store (BytecodeStream *i, Bytecodes::Code bc, Bytecodes::Code bc0, unsigned int varNo);
431
432 void expand_current_instr (int bci, int ilen, int newIlen, u_char inst_buffer[]);
433 bool is_astore (BytecodeStream *itr, int *index);
434 bool is_aload (BytecodeStream *itr, int *index);
435
436 // List of bci's where a return address is on top of the stack
437 GrowableArray<intptr_t> *_ret_adr_tos;
438
439 bool stack_top_holds_ret_addr (int bci);
440 void compute_ret_adr_at_TOS ();
441 void update_ret_adr_at_TOS (int bci, int delta);
442
443 int binsToHold (int no) { return ((no+(BitsPerWord-1))/BitsPerWord); }
444 char *state_vec_to_string (CellTypeState* vec, int len);
445
446 // Helper method. Can be used in subclasses to fx. calculate gc_points. If the current instuction
447 // is a control transfer, then calls the jmpFct all possible destinations.
448 void ret_jump_targets_do (BytecodeStream *bcs, jmpFct_t jmpFct, int varNo,int *data);
449 bool jump_targets_do (BytecodeStream *bcs, jmpFct_t jmpFct, int *data);
450
451 friend class RelocCallback;
452 public:
453 GenerateOopMap(methodHandle method);
454
455 // Compute the map.
456 void compute_map(TRAPS);
457 void result_for_basicblock(int bci); // Do a callback on fill_stackmap_for_opcodes for basicblock containing bci
458
459 // Query
460 int max_locals() const { return _max_locals; }
461 methodOop method() const { return _method(); }
462 methodHandle method_as_handle() const { return _method; }
463
464 bool did_rewriting() { return _did_rewriting; }
465 bool did_relocation() { return _did_relocation; }
466
467 static void print_time();
468
469 // Monitor query
470 bool monitor_safe() { return _monitor_safe; }
471
472 // Specialization methods. Intended use:
473 // - possible_gc_point must return true for every bci for which the stackmaps must be returned
474 // - fill_stackmap_prolog is called just before the result is reported. The arguments tells the estimated
475 // number of gc points
476 // - fill_stackmap_for_opcodes is called once for each bytecode index in order (0...code_length-1)
477 // - fill_stackmap_epilog is called after all results has been reported. Note: Since the algorithm does not report
478 // stackmaps for deadcode, fewer gc_points might have been encounted than assumed during the epilog. It is the
479 // responsibility of the subclass to count the correct number.
480 // - fill_init_vars are called once with the result of the init_vars computation
481 //
482 // All these methods are used during a call to: compute_map. Note: Non of the return results are valid
483 // after compute_map returns, since all values are allocated as resource objects.
484 //
485 // All virtual method must be implemented in subclasses
486 virtual bool allow_rewrites () const { return false; }
487 virtual bool report_results () const { return true; }
488 virtual bool report_init_vars () const { return true; }
489 virtual bool possible_gc_point (BytecodeStream *bcs) { ShouldNotReachHere(); return false; }
490 virtual void fill_stackmap_prolog (int nof_gc_points) { ShouldNotReachHere(); }
491 virtual void fill_stackmap_epilog () { ShouldNotReachHere(); }
492 virtual void fill_stackmap_for_opcodes (BytecodeStream *bcs,
493 CellTypeState* vars,
494 CellTypeState* stack,
495 int stackTop) { ShouldNotReachHere(); }
496 virtual void fill_init_vars (GrowableArray<intptr_t> *init_vars) { ShouldNotReachHere();; }
497 };
498
499 //
500 // Subclass of the GenerateOopMap Class that just do rewrites of the method, if needed.
501 // It does not store any oopmaps.
502 //
503 class ResolveOopMapConflicts: public GenerateOopMap {
504 private:
505
506 bool _must_clear_locals;
507
508 virtual bool report_results() const { return false; }
509 virtual bool report_init_vars() const { return true; }
510 virtual bool allow_rewrites() const { return true; }
511 virtual bool possible_gc_point (BytecodeStream *bcs) { return false; }
512 virtual void fill_stackmap_prolog (int nof_gc_points) {}
513 virtual void fill_stackmap_epilog () {}
514 virtual void fill_stackmap_for_opcodes (BytecodeStream *bcs,
515 CellTypeState* vars,
516 CellTypeState* stack,
517 int stack_top) {}
518 virtual void fill_init_vars (GrowableArray<intptr_t> *init_vars) { _must_clear_locals = init_vars->length() > 0; }
519
520 #ifndef PRODUCT
521 // Statistics
522 static int _nof_invocations;
523 static int _nof_rewrites;
524 static int _nof_relocations;
525 #endif
526
527 public:
528 ResolveOopMapConflicts(methodHandle method) : GenerateOopMap(method) { _must_clear_locals = false; };
529
530 methodHandle do_potential_rewrite(TRAPS);
531 bool must_clear_locals() const { return _must_clear_locals; }
532 };
533
534
535 //
536 // Subclass used by the compiler to generate pairing infomation
537 //
538 class GeneratePairingInfo: public GenerateOopMap {
539 private:
540
541 virtual bool report_results() const { return false; }
542 virtual bool report_init_vars() const { return false; }
543 virtual bool allow_rewrites() const { return false; }
544 virtual bool possible_gc_point (BytecodeStream *bcs) { return false; }
545 virtual void fill_stackmap_prolog (int nof_gc_points) {}
546 virtual void fill_stackmap_epilog () {}
547 virtual void fill_stackmap_for_opcodes (BytecodeStream *bcs,
548 CellTypeState* vars,
549 CellTypeState* stack,
550 int stack_top) {}
551 virtual void fill_init_vars (GrowableArray<intptr_t> *init_vars) {}
552 public:
553 GeneratePairingInfo(methodHandle method) : GenerateOopMap(method) {};
554
555 // Call compute_map(CHECK) to generate info.
556 };
557
558
559