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