Mercurial > hg > graal-compiler
annotate src/share/vm/compiler/methodLiveness.cpp @ 1144:9b9c1ee9b3f6
Merge
author | iveresov |
---|---|
date | Wed, 06 Jan 2010 22:21:39 -0800 |
parents | e66fd840cb6b |
children | c18cbe5936b8 |
rev | line source |
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0 | 1 /* |
2 * Copyright 1998-2006 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, | |
20 * CA 95054 USA or visit www.sun.com if you need additional information or | |
21 * have any questions. | |
22 * | |
23 */ | |
24 | |
25 // The MethodLiveness class performs a simple liveness analysis on a method | |
26 // in order to decide which locals are live (that is, will be used again) at | |
27 // a particular bytecode index (bci). | |
28 // | |
29 // The algorithm goes: | |
30 // | |
31 // 1. Break the method into a set of basic blocks. For each basic block we | |
32 // also keep track of its set of predecessors through normal control flow | |
33 // and predecessors through exceptional control flow. | |
34 // | |
35 // 2. For each basic block, compute two sets, gen (the set of values used before | |
36 // they are defined) and kill (the set of values defined before they are used) | |
37 // in the basic block. A basic block "needs" the locals in its gen set to | |
38 // perform its computation. A basic block "provides" values for the locals in | |
39 // its kill set, allowing a need from a successor to be ignored. | |
40 // | |
41 // 3. Liveness information (the set of locals which are needed) is pushed backwards through | |
42 // the program, from blocks to their predecessors. We compute and store liveness | |
43 // information for the normal/exceptional exit paths for each basic block. When | |
44 // this process reaches a fixed point, we are done. | |
45 // | |
46 // 4. When we are asked about the liveness at a particular bci with a basic block, we | |
47 // compute gen/kill sets which represent execution from that bci to the exit of | |
48 // its blocks. We then compose this range gen/kill information with the normal | |
49 // and exceptional exit information for the block to produce liveness information | |
50 // at that bci. | |
51 // | |
52 // The algorithm is approximate in many respects. Notably: | |
53 // | |
54 // 1. We do not do the analysis necessary to match jsr's with the appropriate ret. | |
55 // Instead we make the conservative assumption that any ret can return to any | |
56 // jsr return site. | |
57 // 2. Instead of computing the effects of exceptions at every instruction, we | |
58 // summarize the effects of all exceptional continuations from the block as | |
59 // a single set (_exception_exit), losing some information but simplifying the | |
60 // analysis. | |
61 | |
62 | |
63 # include "incls/_precompiled.incl" | |
64 # include "incls/_methodLiveness.cpp.incl" | |
65 | |
66 //-------------------------------------------------------------------------- | |
67 // The BitCounter class is used for counting the number of bits set in | |
68 // some BitMap. It is only used when collecting liveness statistics. | |
69 | |
70 #ifndef PRODUCT | |
71 | |
72 class BitCounter: public BitMapClosure { | |
73 private: | |
74 int _count; | |
75 public: | |
76 BitCounter() : _count(0) {} | |
77 | |
78 // Callback when bit in map is set | |
342 | 79 virtual bool do_bit(size_t offset) { |
0 | 80 _count++; |
342 | 81 return true; |
0 | 82 } |
83 | |
84 int count() { | |
85 return _count; | |
86 } | |
87 }; | |
88 | |
89 | |
90 //-------------------------------------------------------------------------- | |
91 | |
92 | |
93 // Counts | |
94 long MethodLiveness::_total_bytes = 0; | |
95 int MethodLiveness::_total_methods = 0; | |
96 | |
97 long MethodLiveness::_total_blocks = 0; | |
98 int MethodLiveness::_max_method_blocks = 0; | |
99 | |
100 long MethodLiveness::_total_edges = 0; | |
101 int MethodLiveness::_max_block_edges = 0; | |
102 | |
103 long MethodLiveness::_total_exc_edges = 0; | |
104 int MethodLiveness::_max_block_exc_edges = 0; | |
105 | |
106 long MethodLiveness::_total_method_locals = 0; | |
107 int MethodLiveness::_max_method_locals = 0; | |
108 | |
109 long MethodLiveness::_total_locals_queried = 0; | |
110 long MethodLiveness::_total_live_locals_queried = 0; | |
111 | |
112 long MethodLiveness::_total_visits = 0; | |
113 | |
114 #endif | |
115 | |
116 // Timers | |
117 elapsedTimer MethodLiveness::_time_build_graph; | |
118 elapsedTimer MethodLiveness::_time_gen_kill; | |
119 elapsedTimer MethodLiveness::_time_flow; | |
120 elapsedTimer MethodLiveness::_time_query; | |
121 elapsedTimer MethodLiveness::_time_total; | |
122 | |
123 MethodLiveness::MethodLiveness(Arena* arena, ciMethod* method) | |
124 #ifdef COMPILER1 | |
125 : _bci_block_start((uintptr_t*)arena->Amalloc((method->code_size() >> LogBitsPerByte) + 1), method->code_size()) | |
126 #endif | |
127 { | |
128 _arena = arena; | |
129 _method = method; | |
130 _bit_map_size_bits = method->max_locals(); | |
131 _bit_map_size_words = (_bit_map_size_bits / sizeof(unsigned int)) + 1; | |
132 | |
133 #ifdef COMPILER1 | |
134 _bci_block_start.clear(); | |
135 #endif | |
136 } | |
137 | |
138 void MethodLiveness::compute_liveness() { | |
139 #ifndef PRODUCT | |
140 if (TraceLivenessGen) { | |
141 tty->print_cr("################################################################"); | |
142 tty->print("# Computing liveness information for "); | |
143 method()->print_short_name(); | |
144 } | |
145 | |
146 if (TimeLivenessAnalysis) _time_total.start(); | |
147 #endif | |
148 | |
149 { | |
150 TraceTime buildGraph(NULL, &_time_build_graph, TimeLivenessAnalysis); | |
151 init_basic_blocks(); | |
152 } | |
153 { | |
154 TraceTime genKill(NULL, &_time_gen_kill, TimeLivenessAnalysis); | |
155 init_gen_kill(); | |
156 } | |
157 { | |
158 TraceTime flow(NULL, &_time_flow, TimeLivenessAnalysis); | |
159 propagate_liveness(); | |
160 } | |
161 | |
162 #ifndef PRODUCT | |
163 if (TimeLivenessAnalysis) _time_total.stop(); | |
164 | |
165 if (TimeLivenessAnalysis) { | |
166 // Collect statistics | |
167 _total_bytes += method()->code_size(); | |
168 _total_methods++; | |
169 | |
170 int num_blocks = _block_count; | |
171 _total_blocks += num_blocks; | |
172 _max_method_blocks = MAX2(num_blocks,_max_method_blocks); | |
173 | |
174 for (int i=0; i<num_blocks; i++) { | |
175 BasicBlock *block = _block_list[i]; | |
176 | |
177 int numEdges = block->_normal_predecessors->length(); | |
178 int numExcEdges = block->_exception_predecessors->length(); | |
179 | |
180 _total_edges += numEdges; | |
181 _total_exc_edges += numExcEdges; | |
182 _max_block_edges = MAX2(numEdges,_max_block_edges); | |
183 _max_block_exc_edges = MAX2(numExcEdges,_max_block_exc_edges); | |
184 } | |
185 | |
186 int numLocals = _bit_map_size_bits; | |
187 _total_method_locals += numLocals; | |
188 _max_method_locals = MAX2(numLocals,_max_method_locals); | |
189 } | |
190 #endif | |
191 } | |
192 | |
193 | |
194 void MethodLiveness::init_basic_blocks() { | |
195 bool bailout = false; | |
196 | |
197 int method_len = method()->code_size(); | |
198 ciMethodBlocks *mblocks = method()->get_method_blocks(); | |
199 | |
200 // Create an array to store the bci->BasicBlock mapping. | |
201 _block_map = new (arena()) GrowableArray<BasicBlock*>(arena(), method_len, method_len, NULL); | |
202 | |
203 _block_count = mblocks->num_blocks(); | |
204 _block_list = (BasicBlock **) arena()->Amalloc(sizeof(BasicBlock *) * _block_count); | |
205 | |
206 // Used for patching up jsr/ret control flow. | |
207 GrowableArray<BasicBlock*>* jsr_exit_list = new GrowableArray<BasicBlock*>(5); | |
208 GrowableArray<BasicBlock*>* ret_list = new GrowableArray<BasicBlock*>(5); | |
209 | |
210 // generate our block list from ciMethodBlocks | |
211 for (int blk = 0; blk < _block_count; blk++) { | |
212 ciBlock *cib = mblocks->block(blk); | |
213 int start_bci = cib->start_bci(); | |
214 _block_list[blk] = new (arena()) BasicBlock(this, start_bci, cib->limit_bci()); | |
215 _block_map->at_put(start_bci, _block_list[blk]); | |
216 #ifdef COMPILER1 | |
217 // mark all bcis where a new basic block starts | |
218 _bci_block_start.set_bit(start_bci); | |
219 #endif // COMPILER1 | |
220 } | |
221 // fill in the predecessors of blocks | |
222 ciBytecodeStream bytes(method()); | |
223 | |
224 for (int blk = 0; blk < _block_count; blk++) { | |
225 BasicBlock *current_block = _block_list[blk]; | |
226 int bci = mblocks->block(blk)->control_bci(); | |
227 | |
228 if (bci == ciBlock::fall_through_bci) { | |
229 int limit = current_block->limit_bci(); | |
230 if (limit < method_len) { | |
231 BasicBlock *next = _block_map->at(limit); | |
232 assert( next != NULL, "must be a block immediately following this one."); | |
233 next->add_normal_predecessor(current_block); | |
234 } | |
235 continue; | |
236 } | |
237 bytes.reset_to_bci(bci); | |
238 Bytecodes::Code code = bytes.next(); | |
239 BasicBlock *dest; | |
240 | |
241 // Now we need to interpret the instruction's effect | |
242 // on control flow. | |
243 assert (current_block != NULL, "we must have a current block"); | |
244 switch (code) { | |
245 case Bytecodes::_ifeq: | |
246 case Bytecodes::_ifne: | |
247 case Bytecodes::_iflt: | |
248 case Bytecodes::_ifge: | |
249 case Bytecodes::_ifgt: | |
250 case Bytecodes::_ifle: | |
251 case Bytecodes::_if_icmpeq: | |
252 case Bytecodes::_if_icmpne: | |
253 case Bytecodes::_if_icmplt: | |
254 case Bytecodes::_if_icmpge: | |
255 case Bytecodes::_if_icmpgt: | |
256 case Bytecodes::_if_icmple: | |
257 case Bytecodes::_if_acmpeq: | |
258 case Bytecodes::_if_acmpne: | |
259 case Bytecodes::_ifnull: | |
260 case Bytecodes::_ifnonnull: | |
261 // Two way branch. Set predecessors at each destination. | |
262 dest = _block_map->at(bytes.next_bci()); | |
263 assert(dest != NULL, "must be a block immediately following this one."); | |
264 dest->add_normal_predecessor(current_block); | |
265 | |
266 dest = _block_map->at(bytes.get_dest()); | |
267 assert(dest != NULL, "branch desination must start a block."); | |
268 dest->add_normal_predecessor(current_block); | |
269 break; | |
270 case Bytecodes::_goto: | |
271 dest = _block_map->at(bytes.get_dest()); | |
272 assert(dest != NULL, "branch desination must start a block."); | |
273 dest->add_normal_predecessor(current_block); | |
274 break; | |
275 case Bytecodes::_goto_w: | |
276 dest = _block_map->at(bytes.get_far_dest()); | |
277 assert(dest != NULL, "branch desination must start a block."); | |
278 dest->add_normal_predecessor(current_block); | |
279 break; | |
280 case Bytecodes::_tableswitch: | |
281 { | |
282 Bytecode_tableswitch *tableswitch = | |
283 Bytecode_tableswitch_at(bytes.cur_bcp()); | |
284 | |
285 int len = tableswitch->length(); | |
286 | |
287 dest = _block_map->at(bci + tableswitch->default_offset()); | |
288 assert(dest != NULL, "branch desination must start a block."); | |
289 dest->add_normal_predecessor(current_block); | |
290 while (--len >= 0) { | |
291 dest = _block_map->at(bci + tableswitch->dest_offset_at(len)); | |
292 assert(dest != NULL, "branch desination must start a block."); | |
293 dest->add_normal_predecessor(current_block); | |
294 } | |
295 break; | |
296 } | |
297 | |
298 case Bytecodes::_lookupswitch: | |
299 { | |
300 Bytecode_lookupswitch *lookupswitch = | |
301 Bytecode_lookupswitch_at(bytes.cur_bcp()); | |
302 | |
303 int npairs = lookupswitch->number_of_pairs(); | |
304 | |
305 dest = _block_map->at(bci + lookupswitch->default_offset()); | |
306 assert(dest != NULL, "branch desination must start a block."); | |
307 dest->add_normal_predecessor(current_block); | |
308 while(--npairs >= 0) { | |
309 LookupswitchPair *pair = lookupswitch->pair_at(npairs); | |
310 dest = _block_map->at( bci + pair->offset()); | |
311 assert(dest != NULL, "branch desination must start a block."); | |
312 dest->add_normal_predecessor(current_block); | |
313 } | |
314 break; | |
315 } | |
316 | |
317 case Bytecodes::_jsr: | |
318 { | |
319 assert(bytes.is_wide()==false, "sanity check"); | |
320 dest = _block_map->at(bytes.get_dest()); | |
321 assert(dest != NULL, "branch desination must start a block."); | |
322 dest->add_normal_predecessor(current_block); | |
323 BasicBlock *jsrExit = _block_map->at(current_block->limit_bci()); | |
324 assert(jsrExit != NULL, "jsr return bci must start a block."); | |
325 jsr_exit_list->append(jsrExit); | |
326 break; | |
327 } | |
328 case Bytecodes::_jsr_w: | |
329 { | |
330 dest = _block_map->at(bytes.get_far_dest()); | |
331 assert(dest != NULL, "branch desination must start a block."); | |
332 dest->add_normal_predecessor(current_block); | |
333 BasicBlock *jsrExit = _block_map->at(current_block->limit_bci()); | |
334 assert(jsrExit != NULL, "jsr return bci must start a block."); | |
335 jsr_exit_list->append(jsrExit); | |
336 break; | |
337 } | |
338 | |
339 case Bytecodes::_wide: | |
340 assert(false, "wide opcodes should not be seen here"); | |
341 break; | |
342 case Bytecodes::_athrow: | |
343 case Bytecodes::_ireturn: | |
344 case Bytecodes::_lreturn: | |
345 case Bytecodes::_freturn: | |
346 case Bytecodes::_dreturn: | |
347 case Bytecodes::_areturn: | |
348 case Bytecodes::_return: | |
349 // These opcodes are not the normal predecessors of any other opcodes. | |
350 break; | |
351 case Bytecodes::_ret: | |
352 // We will patch up jsr/rets in a subsequent pass. | |
353 ret_list->append(current_block); | |
354 break; | |
355 case Bytecodes::_breakpoint: | |
356 // Bail out of there are breakpoints in here. | |
357 bailout = true; | |
358 break; | |
359 default: | |
360 // Do nothing. | |
361 break; | |
362 } | |
363 } | |
364 // Patch up the jsr/ret's. We conservatively assume that any ret | |
365 // can return to any jsr site. | |
366 int ret_list_len = ret_list->length(); | |
367 int jsr_exit_list_len = jsr_exit_list->length(); | |
368 if (ret_list_len > 0 && jsr_exit_list_len > 0) { | |
369 for (int i = jsr_exit_list_len - 1; i >= 0; i--) { | |
370 BasicBlock *jsrExit = jsr_exit_list->at(i); | |
371 for (int i = ret_list_len - 1; i >= 0; i--) { | |
372 jsrExit->add_normal_predecessor(ret_list->at(i)); | |
373 } | |
374 } | |
375 } | |
376 | |
377 // Compute exception edges. | |
378 for (int b=_block_count-1; b >= 0; b--) { | |
379 BasicBlock *block = _block_list[b]; | |
380 int block_start = block->start_bci(); | |
381 int block_limit = block->limit_bci(); | |
382 ciExceptionHandlerStream handlers(method()); | |
383 for (; !handlers.is_done(); handlers.next()) { | |
384 ciExceptionHandler* handler = handlers.handler(); | |
385 int start = handler->start(); | |
386 int limit = handler->limit(); | |
387 int handler_bci = handler->handler_bci(); | |
388 | |
389 int intersect_start = MAX2(block_start, start); | |
390 int intersect_limit = MIN2(block_limit, limit); | |
391 if (intersect_start < intersect_limit) { | |
392 // The catch range has a nonempty intersection with this | |
393 // basic block. That means this basic block can be an | |
394 // exceptional predecessor. | |
395 _block_map->at(handler_bci)->add_exception_predecessor(block); | |
396 | |
397 if (handler->is_catch_all()) { | |
398 // This is a catch-all block. | |
399 if (intersect_start == block_start && intersect_limit == block_limit) { | |
400 // The basic block is entirely contained in this catch-all block. | |
401 // Skip the rest of the exception handlers -- they can never be | |
402 // reached in execution. | |
403 break; | |
404 } | |
405 } | |
406 } | |
407 } | |
408 } | |
409 } | |
410 | |
411 void MethodLiveness::init_gen_kill() { | |
412 for (int i=_block_count-1; i >= 0; i--) { | |
413 _block_list[i]->compute_gen_kill(method()); | |
414 } | |
415 } | |
416 | |
417 void MethodLiveness::propagate_liveness() { | |
418 int num_blocks = _block_count; | |
419 BasicBlock *block; | |
420 | |
421 // We start our work list off with all blocks in it. | |
422 // Alternately, we could start off the work list with the list of all | |
423 // blocks which could exit the method directly, along with one block | |
424 // from any infinite loop. If this matters, it can be changed. It | |
425 // may not be clear from looking at the code, but the order of the | |
426 // workList will be the opposite of the creation order of the basic | |
427 // blocks, which should be decent for quick convergence (with the | |
428 // possible exception of exception handlers, which are all created | |
429 // early). | |
430 _work_list = NULL; | |
431 for (int i = 0; i < num_blocks; i++) { | |
432 block = _block_list[i]; | |
433 block->set_next(_work_list); | |
434 block->set_on_work_list(true); | |
435 _work_list = block; | |
436 } | |
437 | |
438 | |
439 while ((block = work_list_get()) != NULL) { | |
440 block->propagate(this); | |
441 NOT_PRODUCT(_total_visits++;) | |
442 } | |
443 } | |
444 | |
445 void MethodLiveness::work_list_add(BasicBlock *block) { | |
446 if (!block->on_work_list()) { | |
447 block->set_next(_work_list); | |
448 block->set_on_work_list(true); | |
449 _work_list = block; | |
450 } | |
451 } | |
452 | |
453 MethodLiveness::BasicBlock *MethodLiveness::work_list_get() { | |
454 BasicBlock *block = _work_list; | |
455 if (block != NULL) { | |
456 block->set_on_work_list(false); | |
457 _work_list = block->next(); | |
458 } | |
459 return block; | |
460 } | |
461 | |
462 | |
463 MethodLivenessResult MethodLiveness::get_liveness_at(int entry_bci) { | |
464 int bci = entry_bci; | |
465 bool is_entry = false; | |
466 if (entry_bci == InvocationEntryBci) { | |
467 is_entry = true; | |
468 bci = 0; | |
469 } | |
470 | |
342 | 471 MethodLivenessResult answer((uintptr_t*)NULL,0); |
0 | 472 |
473 if (_block_count > 0) { | |
474 if (TimeLivenessAnalysis) _time_total.start(); | |
475 if (TimeLivenessAnalysis) _time_query.start(); | |
476 | |
477 assert( 0 <= bci && bci < method()->code_size(), "bci out of range" ); | |
478 BasicBlock *block = _block_map->at(bci); | |
479 // We may not be at the block start, so search backwards to find the block | |
480 // containing bci. | |
481 int t = bci; | |
482 while (block == NULL && t > 0) { | |
483 block = _block_map->at(--t); | |
484 } | |
485 assert( block != NULL, "invalid bytecode index; must be instruction index" ); | |
486 assert(bci >= block->start_bci() && bci < block->limit_bci(), "block must contain bci."); | |
487 | |
488 answer = block->get_liveness_at(method(), bci); | |
489 | |
490 if (is_entry && method()->is_synchronized() && !method()->is_static()) { | |
491 // Synchronized methods use the receiver once on entry. | |
492 answer.at_put(0, true); | |
493 } | |
494 | |
495 #ifndef PRODUCT | |
496 if (TraceLivenessQuery) { | |
497 tty->print("Liveness query of "); | |
498 method()->print_short_name(); | |
499 tty->print(" @ %d : result is ", bci); | |
500 answer.print_on(tty); | |
501 } | |
502 | |
503 if (TimeLivenessAnalysis) _time_query.stop(); | |
504 if (TimeLivenessAnalysis) _time_total.stop(); | |
505 #endif | |
506 } | |
507 | |
508 #ifndef PRODUCT | |
509 if (TimeLivenessAnalysis) { | |
510 // Collect statistics. | |
511 _total_locals_queried += _bit_map_size_bits; | |
512 BitCounter counter; | |
513 answer.iterate(&counter); | |
514 _total_live_locals_queried += counter.count(); | |
515 } | |
516 #endif | |
517 | |
518 return answer; | |
519 } | |
520 | |
521 | |
522 #ifndef PRODUCT | |
523 | |
524 void MethodLiveness::print_times() { | |
525 tty->print_cr ("Accumulated liveness analysis times/statistics:"); | |
526 tty->print_cr ("-----------------------------------------------"); | |
527 tty->print_cr (" Total : %3.3f sec.", _time_total.seconds()); | |
528 tty->print_cr (" Build graph : %3.3f sec. (%2.2f%%)", _time_build_graph.seconds(), | |
529 _time_build_graph.seconds() * 100 / _time_total.seconds()); | |
530 tty->print_cr (" Gen / Kill : %3.3f sec. (%2.2f%%)", _time_gen_kill.seconds(), | |
531 _time_gen_kill.seconds() * 100 / _time_total.seconds()); | |
532 tty->print_cr (" Dataflow : %3.3f sec. (%2.2f%%)", _time_flow.seconds(), | |
533 _time_flow.seconds() * 100 / _time_total.seconds()); | |
534 tty->print_cr (" Query : %3.3f sec. (%2.2f%%)", _time_query.seconds(), | |
535 _time_query.seconds() * 100 / _time_total.seconds()); | |
536 tty->print_cr (" #bytes : %8d (%3.0f bytes per sec)", | |
537 _total_bytes, | |
538 _total_bytes / _time_total.seconds()); | |
539 tty->print_cr (" #methods : %8d (%3.0f methods per sec)", | |
540 _total_methods, | |
541 _total_methods / _time_total.seconds()); | |
542 tty->print_cr (" avg locals : %3.3f max locals : %3d", | |
543 (float)_total_method_locals / _total_methods, | |
544 _max_method_locals); | |
545 tty->print_cr (" avg blocks : %3.3f max blocks : %3d", | |
546 (float)_total_blocks / _total_methods, | |
547 _max_method_blocks); | |
548 tty->print_cr (" avg bytes : %3.3f", | |
549 (float)_total_bytes / _total_methods); | |
550 tty->print_cr (" #blocks : %8d", | |
551 _total_blocks); | |
552 tty->print_cr (" avg normal predecessors : %3.3f max normal predecessors : %3d", | |
553 (float)_total_edges / _total_blocks, | |
554 _max_block_edges); | |
555 tty->print_cr (" avg exception predecessors : %3.3f max exception predecessors : %3d", | |
556 (float)_total_exc_edges / _total_blocks, | |
557 _max_block_exc_edges); | |
558 tty->print_cr (" avg visits : %3.3f", | |
559 (float)_total_visits / _total_blocks); | |
560 tty->print_cr (" #locals queried : %8d #live : %8d %%live : %2.2f%%", | |
561 _total_locals_queried, | |
562 _total_live_locals_queried, | |
563 100.0 * _total_live_locals_queried / _total_locals_queried); | |
564 } | |
565 | |
566 #endif | |
567 | |
568 | |
569 MethodLiveness::BasicBlock::BasicBlock(MethodLiveness *analyzer, int start, int limit) : | |
570 _gen((uintptr_t*)analyzer->arena()->Amalloc(BytesPerWord * analyzer->bit_map_size_words()), | |
571 analyzer->bit_map_size_bits()), | |
572 _kill((uintptr_t*)analyzer->arena()->Amalloc(BytesPerWord * analyzer->bit_map_size_words()), | |
573 analyzer->bit_map_size_bits()), | |
574 _entry((uintptr_t*)analyzer->arena()->Amalloc(BytesPerWord * analyzer->bit_map_size_words()), | |
575 analyzer->bit_map_size_bits()), | |
576 _normal_exit((uintptr_t*)analyzer->arena()->Amalloc(BytesPerWord * analyzer->bit_map_size_words()), | |
577 analyzer->bit_map_size_bits()), | |
578 _exception_exit((uintptr_t*)analyzer->arena()->Amalloc(BytesPerWord * analyzer->bit_map_size_words()), | |
579 analyzer->bit_map_size_bits()), | |
580 _last_bci(-1) { | |
581 _analyzer = analyzer; | |
582 _start_bci = start; | |
583 _limit_bci = limit; | |
584 _normal_predecessors = | |
585 new (analyzer->arena()) GrowableArray<MethodLiveness::BasicBlock*>(analyzer->arena(), 5, 0, NULL); | |
586 _exception_predecessors = | |
587 new (analyzer->arena()) GrowableArray<MethodLiveness::BasicBlock*>(analyzer->arena(), 5, 0, NULL); | |
588 _normal_exit.clear(); | |
589 _exception_exit.clear(); | |
590 _entry.clear(); | |
591 | |
592 // this initialization is not strictly necessary. | |
593 // _gen and _kill are cleared at the beginning of compute_gen_kill_range() | |
594 _gen.clear(); | |
595 _kill.clear(); | |
596 } | |
597 | |
598 | |
599 | |
600 MethodLiveness::BasicBlock *MethodLiveness::BasicBlock::split(int split_bci) { | |
601 int start = _start_bci; | |
602 int limit = _limit_bci; | |
603 | |
604 if (TraceLivenessGen) { | |
605 tty->print_cr(" ** Splitting block (%d,%d) at %d", start, limit, split_bci); | |
606 } | |
607 | |
608 GrowableArray<BasicBlock*>* save_predecessors = _normal_predecessors; | |
609 | |
610 assert (start < split_bci && split_bci < limit, "improper split"); | |
611 | |
612 // Make a new block to cover the first half of the range. | |
613 BasicBlock *first_half = new (_analyzer->arena()) BasicBlock(_analyzer, start, split_bci); | |
614 | |
615 // Assign correct values to the second half (this) | |
616 _normal_predecessors = first_half->_normal_predecessors; | |
617 _start_bci = split_bci; | |
618 add_normal_predecessor(first_half); | |
619 | |
620 // Assign correct predecessors to the new first half | |
621 first_half->_normal_predecessors = save_predecessors; | |
622 | |
623 return first_half; | |
624 } | |
625 | |
626 void MethodLiveness::BasicBlock::compute_gen_kill(ciMethod* method) { | |
627 ciBytecodeStream bytes(method); | |
628 bytes.reset_to_bci(start_bci()); | |
629 bytes.set_max_bci(limit_bci()); | |
630 compute_gen_kill_range(&bytes); | |
631 | |
632 } | |
633 | |
634 void MethodLiveness::BasicBlock::compute_gen_kill_range(ciBytecodeStream *bytes) { | |
635 _gen.clear(); | |
636 _kill.clear(); | |
637 | |
638 while (bytes->next() != ciBytecodeStream::EOBC()) { | |
639 compute_gen_kill_single(bytes); | |
640 } | |
641 } | |
642 | |
643 void MethodLiveness::BasicBlock::compute_gen_kill_single(ciBytecodeStream *instruction) { | |
644 int localNum; | |
645 | |
646 // We prohibit _gen and _kill from having locals in common. If we | |
647 // know that one is definitely going to be applied before the other, | |
648 // we could save some computation time by relaxing this prohibition. | |
649 | |
650 switch (instruction->cur_bc()) { | |
651 case Bytecodes::_nop: | |
652 case Bytecodes::_goto: | |
653 case Bytecodes::_goto_w: | |
654 case Bytecodes::_aconst_null: | |
655 case Bytecodes::_new: | |
656 case Bytecodes::_iconst_m1: | |
657 case Bytecodes::_iconst_0: | |
658 case Bytecodes::_iconst_1: | |
659 case Bytecodes::_iconst_2: | |
660 case Bytecodes::_iconst_3: | |
661 case Bytecodes::_iconst_4: | |
662 case Bytecodes::_iconst_5: | |
663 case Bytecodes::_fconst_0: | |
664 case Bytecodes::_fconst_1: | |
665 case Bytecodes::_fconst_2: | |
666 case Bytecodes::_bipush: | |
667 case Bytecodes::_sipush: | |
668 case Bytecodes::_lconst_0: | |
669 case Bytecodes::_lconst_1: | |
670 case Bytecodes::_dconst_0: | |
671 case Bytecodes::_dconst_1: | |
672 case Bytecodes::_ldc2_w: | |
673 case Bytecodes::_ldc: | |
674 case Bytecodes::_ldc_w: | |
675 case Bytecodes::_iaload: | |
676 case Bytecodes::_faload: | |
677 case Bytecodes::_baload: | |
678 case Bytecodes::_caload: | |
679 case Bytecodes::_saload: | |
680 case Bytecodes::_laload: | |
681 case Bytecodes::_daload: | |
682 case Bytecodes::_aaload: | |
683 case Bytecodes::_iastore: | |
684 case Bytecodes::_fastore: | |
685 case Bytecodes::_bastore: | |
686 case Bytecodes::_castore: | |
687 case Bytecodes::_sastore: | |
688 case Bytecodes::_lastore: | |
689 case Bytecodes::_dastore: | |
690 case Bytecodes::_aastore: | |
691 case Bytecodes::_pop: | |
692 case Bytecodes::_pop2: | |
693 case Bytecodes::_dup: | |
694 case Bytecodes::_dup_x1: | |
695 case Bytecodes::_dup_x2: | |
696 case Bytecodes::_dup2: | |
697 case Bytecodes::_dup2_x1: | |
698 case Bytecodes::_dup2_x2: | |
699 case Bytecodes::_swap: | |
700 case Bytecodes::_iadd: | |
701 case Bytecodes::_fadd: | |
702 case Bytecodes::_isub: | |
703 case Bytecodes::_fsub: | |
704 case Bytecodes::_imul: | |
705 case Bytecodes::_fmul: | |
706 case Bytecodes::_idiv: | |
707 case Bytecodes::_fdiv: | |
708 case Bytecodes::_irem: | |
709 case Bytecodes::_frem: | |
710 case Bytecodes::_ishl: | |
711 case Bytecodes::_ishr: | |
712 case Bytecodes::_iushr: | |
713 case Bytecodes::_iand: | |
714 case Bytecodes::_ior: | |
715 case Bytecodes::_ixor: | |
716 case Bytecodes::_l2f: | |
717 case Bytecodes::_l2i: | |
718 case Bytecodes::_d2f: | |
719 case Bytecodes::_d2i: | |
720 case Bytecodes::_fcmpl: | |
721 case Bytecodes::_fcmpg: | |
722 case Bytecodes::_ladd: | |
723 case Bytecodes::_dadd: | |
724 case Bytecodes::_lsub: | |
725 case Bytecodes::_dsub: | |
726 case Bytecodes::_lmul: | |
727 case Bytecodes::_dmul: | |
728 case Bytecodes::_ldiv: | |
729 case Bytecodes::_ddiv: | |
730 case Bytecodes::_lrem: | |
731 case Bytecodes::_drem: | |
732 case Bytecodes::_land: | |
733 case Bytecodes::_lor: | |
734 case Bytecodes::_lxor: | |
735 case Bytecodes::_ineg: | |
736 case Bytecodes::_fneg: | |
737 case Bytecodes::_i2f: | |
738 case Bytecodes::_f2i: | |
739 case Bytecodes::_i2c: | |
740 case Bytecodes::_i2s: | |
741 case Bytecodes::_i2b: | |
742 case Bytecodes::_lneg: | |
743 case Bytecodes::_dneg: | |
744 case Bytecodes::_l2d: | |
745 case Bytecodes::_d2l: | |
746 case Bytecodes::_lshl: | |
747 case Bytecodes::_lshr: | |
748 case Bytecodes::_lushr: | |
749 case Bytecodes::_i2l: | |
750 case Bytecodes::_i2d: | |
751 case Bytecodes::_f2l: | |
752 case Bytecodes::_f2d: | |
753 case Bytecodes::_lcmp: | |
754 case Bytecodes::_dcmpl: | |
755 case Bytecodes::_dcmpg: | |
756 case Bytecodes::_ifeq: | |
757 case Bytecodes::_ifne: | |
758 case Bytecodes::_iflt: | |
759 case Bytecodes::_ifge: | |
760 case Bytecodes::_ifgt: | |
761 case Bytecodes::_ifle: | |
762 case Bytecodes::_tableswitch: | |
763 case Bytecodes::_ireturn: | |
764 case Bytecodes::_freturn: | |
765 case Bytecodes::_if_icmpeq: | |
766 case Bytecodes::_if_icmpne: | |
767 case Bytecodes::_if_icmplt: | |
768 case Bytecodes::_if_icmpge: | |
769 case Bytecodes::_if_icmpgt: | |
770 case Bytecodes::_if_icmple: | |
771 case Bytecodes::_lreturn: | |
772 case Bytecodes::_dreturn: | |
773 case Bytecodes::_if_acmpeq: | |
774 case Bytecodes::_if_acmpne: | |
775 case Bytecodes::_jsr: | |
776 case Bytecodes::_jsr_w: | |
777 case Bytecodes::_getstatic: | |
778 case Bytecodes::_putstatic: | |
779 case Bytecodes::_getfield: | |
780 case Bytecodes::_putfield: | |
781 case Bytecodes::_invokevirtual: | |
782 case Bytecodes::_invokespecial: | |
783 case Bytecodes::_invokestatic: | |
784 case Bytecodes::_invokeinterface: | |
1135
e66fd840cb6b
6893081: method handle & invokedynamic code needs additional cleanup (post 6815692, 6858164)
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parents:
342
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changeset
|
785 case Bytecodes::_invokedynamic: |
0 | 786 case Bytecodes::_newarray: |
787 case Bytecodes::_anewarray: | |
788 case Bytecodes::_checkcast: | |
789 case Bytecodes::_arraylength: | |
790 case Bytecodes::_instanceof: | |
791 case Bytecodes::_athrow: | |
792 case Bytecodes::_areturn: | |
793 case Bytecodes::_monitorenter: | |
794 case Bytecodes::_monitorexit: | |
795 case Bytecodes::_ifnull: | |
796 case Bytecodes::_ifnonnull: | |
797 case Bytecodes::_multianewarray: | |
798 case Bytecodes::_lookupswitch: | |
799 // These bytecodes have no effect on the method's locals. | |
800 break; | |
801 | |
802 case Bytecodes::_return: | |
803 if (instruction->method()->intrinsic_id() == vmIntrinsics::_Object_init) { | |
804 // return from Object.init implicitly registers a finalizer | |
805 // for the receiver if needed, so keep it alive. | |
806 load_one(0); | |
807 } | |
808 break; | |
809 | |
810 | |
811 case Bytecodes::_lload: | |
812 case Bytecodes::_dload: | |
813 load_two(instruction->get_index()); | |
814 break; | |
815 | |
816 case Bytecodes::_lload_0: | |
817 case Bytecodes::_dload_0: | |
818 load_two(0); | |
819 break; | |
820 | |
821 case Bytecodes::_lload_1: | |
822 case Bytecodes::_dload_1: | |
823 load_two(1); | |
824 break; | |
825 | |
826 case Bytecodes::_lload_2: | |
827 case Bytecodes::_dload_2: | |
828 load_two(2); | |
829 break; | |
830 | |
831 case Bytecodes::_lload_3: | |
832 case Bytecodes::_dload_3: | |
833 load_two(3); | |
834 break; | |
835 | |
836 case Bytecodes::_iload: | |
837 case Bytecodes::_iinc: | |
838 case Bytecodes::_fload: | |
839 case Bytecodes::_aload: | |
840 case Bytecodes::_ret: | |
841 load_one(instruction->get_index()); | |
842 break; | |
843 | |
844 case Bytecodes::_iload_0: | |
845 case Bytecodes::_fload_0: | |
846 case Bytecodes::_aload_0: | |
847 load_one(0); | |
848 break; | |
849 | |
850 case Bytecodes::_iload_1: | |
851 case Bytecodes::_fload_1: | |
852 case Bytecodes::_aload_1: | |
853 load_one(1); | |
854 break; | |
855 | |
856 case Bytecodes::_iload_2: | |
857 case Bytecodes::_fload_2: | |
858 case Bytecodes::_aload_2: | |
859 load_one(2); | |
860 break; | |
861 | |
862 case Bytecodes::_iload_3: | |
863 case Bytecodes::_fload_3: | |
864 case Bytecodes::_aload_3: | |
865 load_one(3); | |
866 break; | |
867 | |
868 case Bytecodes::_lstore: | |
869 case Bytecodes::_dstore: | |
870 store_two(localNum = instruction->get_index()); | |
871 break; | |
872 | |
873 case Bytecodes::_lstore_0: | |
874 case Bytecodes::_dstore_0: | |
875 store_two(0); | |
876 break; | |
877 | |
878 case Bytecodes::_lstore_1: | |
879 case Bytecodes::_dstore_1: | |
880 store_two(1); | |
881 break; | |
882 | |
883 case Bytecodes::_lstore_2: | |
884 case Bytecodes::_dstore_2: | |
885 store_two(2); | |
886 break; | |
887 | |
888 case Bytecodes::_lstore_3: | |
889 case Bytecodes::_dstore_3: | |
890 store_two(3); | |
891 break; | |
892 | |
893 case Bytecodes::_istore: | |
894 case Bytecodes::_fstore: | |
895 case Bytecodes::_astore: | |
896 store_one(instruction->get_index()); | |
897 break; | |
898 | |
899 case Bytecodes::_istore_0: | |
900 case Bytecodes::_fstore_0: | |
901 case Bytecodes::_astore_0: | |
902 store_one(0); | |
903 break; | |
904 | |
905 case Bytecodes::_istore_1: | |
906 case Bytecodes::_fstore_1: | |
907 case Bytecodes::_astore_1: | |
908 store_one(1); | |
909 break; | |
910 | |
911 case Bytecodes::_istore_2: | |
912 case Bytecodes::_fstore_2: | |
913 case Bytecodes::_astore_2: | |
914 store_one(2); | |
915 break; | |
916 | |
917 case Bytecodes::_istore_3: | |
918 case Bytecodes::_fstore_3: | |
919 case Bytecodes::_astore_3: | |
920 store_one(3); | |
921 break; | |
922 | |
923 case Bytecodes::_wide: | |
924 fatal("Iterator should skip this bytecode"); | |
925 break; | |
926 | |
927 default: | |
928 tty->print("unexpected opcode: %d\n", instruction->cur_bc()); | |
929 ShouldNotReachHere(); | |
930 break; | |
931 } | |
932 } | |
933 | |
934 void MethodLiveness::BasicBlock::load_two(int local) { | |
935 load_one(local); | |
936 load_one(local+1); | |
937 } | |
938 | |
939 void MethodLiveness::BasicBlock::load_one(int local) { | |
940 if (!_kill.at(local)) { | |
941 _gen.at_put(local, true); | |
942 } | |
943 } | |
944 | |
945 void MethodLiveness::BasicBlock::store_two(int local) { | |
946 store_one(local); | |
947 store_one(local+1); | |
948 } | |
949 | |
950 void MethodLiveness::BasicBlock::store_one(int local) { | |
951 if (!_gen.at(local)) { | |
952 _kill.at_put(local, true); | |
953 } | |
954 } | |
955 | |
956 void MethodLiveness::BasicBlock::propagate(MethodLiveness *ml) { | |
957 // These set operations could be combined for efficiency if the | |
958 // performance of this analysis becomes an issue. | |
959 _entry.set_union(_normal_exit); | |
960 _entry.set_difference(_kill); | |
961 _entry.set_union(_gen); | |
962 | |
963 // Note that we merge information from our exceptional successors | |
964 // just once, rather than at individual bytecodes. | |
965 _entry.set_union(_exception_exit); | |
966 | |
967 if (TraceLivenessGen) { | |
968 tty->print_cr(" ** Visiting block at %d **", start_bci()); | |
969 print_on(tty); | |
970 } | |
971 | |
972 int i; | |
973 for (i=_normal_predecessors->length()-1; i>=0; i--) { | |
974 BasicBlock *block = _normal_predecessors->at(i); | |
975 if (block->merge_normal(_entry)) { | |
976 ml->work_list_add(block); | |
977 } | |
978 } | |
979 for (i=_exception_predecessors->length()-1; i>=0; i--) { | |
980 BasicBlock *block = _exception_predecessors->at(i); | |
981 if (block->merge_exception(_entry)) { | |
982 ml->work_list_add(block); | |
983 } | |
984 } | |
985 } | |
986 | |
987 bool MethodLiveness::BasicBlock::merge_normal(BitMap other) { | |
988 return _normal_exit.set_union_with_result(other); | |
989 } | |
990 | |
991 bool MethodLiveness::BasicBlock::merge_exception(BitMap other) { | |
992 return _exception_exit.set_union_with_result(other); | |
993 } | |
994 | |
995 MethodLivenessResult MethodLiveness::BasicBlock::get_liveness_at(ciMethod* method, int bci) { | |
996 MethodLivenessResult answer(NEW_RESOURCE_ARRAY(uintptr_t, _analyzer->bit_map_size_words()), | |
997 _analyzer->bit_map_size_bits()); | |
998 answer.set_is_valid(); | |
999 | |
1000 #ifndef ASSERT | |
1001 if (bci == start_bci()) { | |
1002 answer.set_from(_entry); | |
1003 return answer; | |
1004 } | |
1005 #endif | |
1006 | |
1007 #ifdef ASSERT | |
1008 ResourceMark rm; | |
1009 BitMap g(_gen.size()); g.set_from(_gen); | |
1010 BitMap k(_kill.size()); k.set_from(_kill); | |
1011 #endif | |
1012 if (_last_bci != bci || trueInDebug) { | |
1013 ciBytecodeStream bytes(method); | |
1014 bytes.reset_to_bci(bci); | |
1015 bytes.set_max_bci(limit_bci()); | |
1016 compute_gen_kill_range(&bytes); | |
1017 assert(_last_bci != bci || | |
1018 (g.is_same(_gen) && k.is_same(_kill)), "cached computation is incorrect"); | |
1019 _last_bci = bci; | |
1020 } | |
1021 | |
1022 answer.clear(); | |
1023 answer.set_union(_normal_exit); | |
1024 answer.set_difference(_kill); | |
1025 answer.set_union(_gen); | |
1026 answer.set_union(_exception_exit); | |
1027 | |
1028 #ifdef ASSERT | |
1029 if (bci == start_bci()) { | |
1030 assert(answer.is_same(_entry), "optimized answer must be accurate"); | |
1031 } | |
1032 #endif | |
1033 | |
1034 return answer; | |
1035 } | |
1036 | |
1037 #ifndef PRODUCT | |
1038 | |
1039 void MethodLiveness::BasicBlock::print_on(outputStream *os) const { | |
1040 os->print_cr("==================================================================="); | |
1041 os->print_cr(" Block start: %4d, limit: %4d", _start_bci, _limit_bci); | |
1042 os->print (" Normal predecessors (%2d) @", _normal_predecessors->length()); | |
1043 int i; | |
1044 for (i=0; i < _normal_predecessors->length(); i++) { | |
1045 os->print(" %4d", _normal_predecessors->at(i)->start_bci()); | |
1046 } | |
1047 os->cr(); | |
1048 os->print (" Exceptional predecessors (%2d) @", _exception_predecessors->length()); | |
1049 for (i=0; i < _exception_predecessors->length(); i++) { | |
1050 os->print(" %4d", _exception_predecessors->at(i)->start_bci()); | |
1051 } | |
1052 os->cr(); | |
1053 os->print (" Normal Exit : "); | |
1054 _normal_exit.print_on(os); | |
1055 os->print (" Gen : "); | |
1056 _gen.print_on(os); | |
1057 os->print (" Kill : "); | |
1058 _kill.print_on(os); | |
1059 os->print (" Exception Exit: "); | |
1060 _exception_exit.print_on(os); | |
1061 os->print (" Entry : "); | |
1062 _entry.print_on(os); | |
1063 } | |
1064 | |
1065 #endif // PRODUCT |