1 /*
2 * Copyright (c) 2000, 2011, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "code/compiledIC.hpp"
27 #include "code/nmethod.hpp"
28 #include "code/scopeDesc.hpp"
29 #include "compiler/compilerOracle.hpp"
30 #include "interpreter/interpreter.hpp"
31 #include "oops/methodDataOop.hpp"
32 #include "oops/methodOop.hpp"
33 #include "oops/oop.inline.hpp"
34 #include "prims/nativeLookup.hpp"
35 #include "runtime/advancedThresholdPolicy.hpp"
36 #include "runtime/compilationPolicy.hpp"
37 #include "runtime/frame.hpp"
38 #include "runtime/handles.inline.hpp"
39 #include "runtime/rframe.hpp"
40 #include "runtime/simpleThresholdPolicy.hpp"
41 #include "runtime/stubRoutines.hpp"
42 #include "runtime/thread.hpp"
43 #include "runtime/timer.hpp"
44 #include "runtime/vframe.hpp"
45 #include "runtime/vm_operations.hpp"
46 #include "utilities/events.hpp"
47 #include "utilities/globalDefinitions.hpp"
48
49 CompilationPolicy* CompilationPolicy::_policy;
50 elapsedTimer CompilationPolicy::_accumulated_time;
51 bool CompilationPolicy::_in_vm_startup;
52
53 // Determine compilation policy based on command line argument
54 void compilationPolicy_init() {
55 CompilationPolicy::set_in_vm_startup(DelayCompilationDuringStartup);
56
57 switch(CompilationPolicyChoice) {
58 case 0:
59 #ifdef COMPILER1
60 if (C1ProfileInlining) {
61 CompilationPolicy::set_policy(new SimpleProfiledCompPolicy());
62 } else {
63 #endif
64 CompilationPolicy::set_policy(new SimpleCompPolicy());
65 #ifdef COMPILER1
66 }
67 #endif
68 break;
69
70 case 1:
71 #ifdef COMPILER2
72 CompilationPolicy::set_policy(new StackWalkCompPolicy());
73 #else
74 Unimplemented();
75 #endif
76 break;
77 case 2:
78 #ifdef TIERED
79 CompilationPolicy::set_policy(new SimpleThresholdPolicy());
80 #else
81 Unimplemented();
82 #endif
83 break;
84 case 3:
85 #ifdef TIERED
86 CompilationPolicy::set_policy(new AdvancedThresholdPolicy());
87 #else
88 Unimplemented();
89 #endif
90 break;
91 default:
92 fatal("CompilationPolicyChoice must be in the range: [0-3]");
93 }
94 CompilationPolicy::policy()->initialize();
95 }
96
97 void CompilationPolicy::completed_vm_startup() {
98 if (TraceCompilationPolicy) {
99 tty->print("CompilationPolicy: completed vm startup.\n");
100 }
101 _in_vm_startup = false;
102 }
103
104 // Returns true if m must be compiled before executing it
105 // This is intended to force compiles for methods (usually for
106 // debugging) that would otherwise be interpreted for some reason.
107 bool CompilationPolicy::must_be_compiled(methodHandle m, int comp_level) {
108 if (m->has_compiled_code()) return false; // already compiled
109 if (!can_be_compiled(m, comp_level)) return false;
110
111 return !UseInterpreter || // must compile all methods
112 (UseCompiler && AlwaysCompileLoopMethods && m->has_loops() && CompileBroker::should_compile_new_jobs()); // eagerly compile loop methods
113 }
114
115 // Returns true if m is allowed to be compiled
116 bool CompilationPolicy::can_be_compiled(methodHandle m, int comp_level) {
117 if (m->is_abstract()) return false;
118 if (DontCompileHugeMethods && m->code_size() > HugeMethodLimit) return false;
119
120 // Math intrinsics should never be compiled as this can lead to
121 // monotonicity problems because the interpreter will prefer the
122 // compiled code to the intrinsic version. This can't happen in
123 // production because the invocation counter can't be incremented
124 // but we shouldn't expose the system to this problem in testing
125 // modes.
126 if (!AbstractInterpreter::can_be_compiled(m)) {
127 return false;
128 }
129 if (comp_level == CompLevel_all) {
130 return !m->is_not_compilable(CompLevel_simple) && !m->is_not_compilable(CompLevel_full_optimization);
131 } else {
132 return !m->is_not_compilable(comp_level);
133 }
134 }
135
136 bool CompilationPolicy::is_compilation_enabled() {
137 // NOTE: CompileBroker::should_compile_new_jobs() checks for UseCompiler
138 return !delay_compilation_during_startup() && CompileBroker::should_compile_new_jobs();
139 }
140
141 #ifndef PRODUCT
142 void CompilationPolicy::print_time() {
143 tty->print_cr ("Accumulated compilationPolicy times:");
144 tty->print_cr ("---------------------------");
145 tty->print_cr (" Total: %3.3f sec.", _accumulated_time.seconds());
146 }
147
148 void NonTieredCompPolicy::trace_osr_completion(nmethod* osr_nm) {
149 if (TraceOnStackReplacement) {
150 if (osr_nm == NULL) tty->print_cr("compilation failed");
151 else tty->print_cr("nmethod " INTPTR_FORMAT, osr_nm);
152 }
153 }
154 #endif // !PRODUCT
155
156 void NonTieredCompPolicy::initialize() {
157 // Setup the compiler thread numbers
158 if (CICompilerCountPerCPU) {
159 // Example: if CICompilerCountPerCPU is true, then we get
160 // max(log2(8)-1,1) = 2 compiler threads on an 8-way machine.
161 // May help big-app startup time.
162 _compiler_count = MAX2(log2_intptr(os::active_processor_count())-1,1);
163 } else {
164 _compiler_count = CICompilerCount;
165 }
166 }
167
168 // Note: this policy is used ONLY if TieredCompilation is off.
169 // compiler_count() behaves the following way:
170 // - with TIERED build (with both COMPILER1 and COMPILER2 defined) it should return
171 // zero for the c1 compilation levels, hence the particular ordering of the
172 // statements.
173 // - the same should happen when COMPILER2 is defined and COMPILER1 is not
174 // (server build without TIERED defined).
175 // - if only COMPILER1 is defined (client build), zero should be returned for
176 // the c2 level.
177 // - if neither is defined - always return zero.
178 int NonTieredCompPolicy::compiler_count(CompLevel comp_level) {
179 assert(!TieredCompilation, "This policy should not be used with TieredCompilation");
180 #ifdef COMPILER2
181 if (is_c2_compile(comp_level)) {
182 return _compiler_count;
183 } else {
184 return 0;
185 }
186 #endif
187
188 #ifdef COMPILER1
189 if (is_c1_compile(comp_level)) {
190 return _compiler_count;
191 } else {
192 return 0;
193 }
194 #endif
195
196 return 0;
197 }
198
199 void NonTieredCompPolicy::reset_counter_for_invocation_event(methodHandle m) {
200 // Make sure invocation and backedge counter doesn't overflow again right away
201 // as would be the case for native methods.
202
203 // BUT also make sure the method doesn't look like it was never executed.
204 // Set carry bit and reduce counter's value to min(count, CompileThreshold/2).
205 m->invocation_counter()->set_carry();
206 m->backedge_counter()->set_carry();
207
208 assert(!m->was_never_executed(), "don't reset to 0 -- could be mistaken for never-executed");
209 }
210
211 void NonTieredCompPolicy::reset_counter_for_back_branch_event(methodHandle m) {
212 // Delay next back-branch event but pump up invocation counter to triger
213 // whole method compilation.
214 InvocationCounter* i = m->invocation_counter();
215 InvocationCounter* b = m->backedge_counter();
216
217 // Don't set invocation_counter's value too low otherwise the method will
218 // look like immature (ic < ~5300) which prevents the inlining based on
219 // the type profiling.
220 i->set(i->state(), CompileThreshold);
221 // Don't reset counter too low - it is used to check if OSR method is ready.
222 b->set(b->state(), CompileThreshold / 2);
223 }
224
225 //
226 // CounterDecay
227 //
228 // Interates through invocation counters and decrements them. This
229 // is done at each safepoint.
230 //
231 class CounterDecay : public AllStatic {
232 static jlong _last_timestamp;
233 static void do_method(methodOop m) {
234 m->invocation_counter()->decay();
235 }
236 public:
237 static void decay();
238 static bool is_decay_needed() {
239 return (os::javaTimeMillis() - _last_timestamp) > CounterDecayMinIntervalLength;
240 }
241 };
242
243 jlong CounterDecay::_last_timestamp = 0;
244
245 void CounterDecay::decay() {
246 _last_timestamp = os::javaTimeMillis();
247
248 // This operation is going to be performed only at the end of a safepoint
249 // and hence GC's will not be going on, all Java mutators are suspended
250 // at this point and hence SystemDictionary_lock is also not needed.
251 assert(SafepointSynchronize::is_at_safepoint(), "can only be executed at a safepoint");
252 int nclasses = SystemDictionary::number_of_classes();
253 double classes_per_tick = nclasses * (CounterDecayMinIntervalLength * 1e-3 /
254 CounterHalfLifeTime);
255 for (int i = 0; i < classes_per_tick; i++) {
256 klassOop k = SystemDictionary::try_get_next_class();
257 if (k != NULL && k->klass_part()->oop_is_instance()) {
258 instanceKlass::cast(k)->methods_do(do_method);
259 }
260 }
261 }
262
263 // Called at the end of the safepoint
264 void NonTieredCompPolicy::do_safepoint_work() {
265 if(UseCounterDecay && CounterDecay::is_decay_needed()) {
266 CounterDecay::decay();
267 }
268 }
269
270 void NonTieredCompPolicy::reprofile(ScopeDesc* trap_scope, bool is_osr) {
271 ScopeDesc* sd = trap_scope;
272 for (; !sd->is_top(); sd = sd->sender()) {
273 // Reset ICs of inlined methods, since they can trigger compilations also.
274 sd->method()->invocation_counter()->reset();
275 }
276 InvocationCounter* c = sd->method()->invocation_counter();
277 if (is_osr) {
278 // It was an OSR method, so bump the count higher.
279 c->set(c->state(), CompileThreshold);
280 } else {
281 c->reset();
282 }
283 sd->method()->backedge_counter()->reset();
284 }
285
286 // This method can be called by any component of the runtime to notify the policy
287 // that it's recommended to delay the complation of this method.
288 void NonTieredCompPolicy::delay_compilation(methodOop method) {
289 method->invocation_counter()->decay();
290 method->backedge_counter()->decay();
291 }
292
293 void NonTieredCompPolicy::disable_compilation(methodOop method) {
294 method->invocation_counter()->set_state(InvocationCounter::wait_for_nothing);
295 method->backedge_counter()->set_state(InvocationCounter::wait_for_nothing);
296 }
297
298 CompileTask* NonTieredCompPolicy::select_task(CompileQueue* compile_queue) {
299 return compile_queue->first();
300 }
301
302 bool NonTieredCompPolicy::is_mature(methodOop method) {
303 methodDataOop mdo = method->method_data();
304 assert(mdo != NULL, "Should be");
305 uint current = mdo->mileage_of(method);
306 uint initial = mdo->creation_mileage();
307 if (current < initial)
308 return true; // some sort of overflow
309 uint target;
310 if (ProfileMaturityPercentage <= 0)
311 target = (uint) -ProfileMaturityPercentage; // absolute value
312 else
313 target = (uint)( (ProfileMaturityPercentage * CompileThreshold) / 100 );
314 return (current >= initial + target);
315 }
316
317 nmethod* NonTieredCompPolicy::event(methodHandle method, methodHandle inlinee, int branch_bci, int bci, CompLevel comp_level, nmethod* nm, TRAPS) {
318 assert(comp_level == CompLevel_none, "This should be only called from the interpreter");
319 NOT_PRODUCT(trace_frequency_counter_overflow(method, branch_bci, bci));
320 if (JvmtiExport::can_post_interpreter_events()) {
321 assert(THREAD->is_Java_thread(), "Wrong type of thread");
322 if (((JavaThread*)THREAD)->is_interp_only_mode()) {
323 // If certain JVMTI events (e.g. frame pop event) are requested then the
324 // thread is forced to remain in interpreted code. This is
325 // implemented partly by a check in the run_compiled_code
326 // section of the interpreter whether we should skip running
327 // compiled code, and partly by skipping OSR compiles for
328 // interpreted-only threads.
329 if (bci != InvocationEntryBci) {
330 reset_counter_for_back_branch_event(method);
331 return NULL;
332 }
333 }
334 }
335 if (bci == InvocationEntryBci) {
336 // when code cache is full, compilation gets switched off, UseCompiler
337 // is set to false
338 if (!method->has_compiled_code() && UseCompiler) {
339 method_invocation_event(method, CHECK_NULL);
340 } else {
341 // Force counter overflow on method entry, even if no compilation
342 // happened. (The method_invocation_event call does this also.)
343 reset_counter_for_invocation_event(method);
344 }
345 // compilation at an invocation overflow no longer goes and retries test for
346 // compiled method. We always run the loser of the race as interpreted.
347 // so return NULL
348 return NULL;
349 } else {
350 // counter overflow in a loop => try to do on-stack-replacement
351 nmethod* osr_nm = method->lookup_osr_nmethod_for(bci, CompLevel_highest_tier, true);
352 NOT_PRODUCT(trace_osr_request(method, osr_nm, bci));
353 // when code cache is full, we should not compile any more...
354 if (osr_nm == NULL && UseCompiler) {
355 method_back_branch_event(method, bci, CHECK_NULL);
356 osr_nm = method->lookup_osr_nmethod_for(bci, CompLevel_highest_tier, true);
357 }
358 if (osr_nm == NULL) {
359 reset_counter_for_back_branch_event(method);
360 return NULL;
361 }
362 return osr_nm;
363 }
364 return NULL;
365 }
366
367 #ifndef PRODUCT
368 void NonTieredCompPolicy::trace_frequency_counter_overflow(methodHandle m, int branch_bci, int bci) {
369 if (TraceInvocationCounterOverflow) {
370 InvocationCounter* ic = m->invocation_counter();
371 InvocationCounter* bc = m->backedge_counter();
372 ResourceMark rm;
373 const char* msg =
374 bci == InvocationEntryBci
375 ? "comp-policy cntr ovfl @ %d in entry of "
376 : "comp-policy cntr ovfl @ %d in loop of ";
377 tty->print(msg, bci);
378 m->print_value();
379 tty->cr();
380 ic->print();
381 bc->print();
382 if (ProfileInterpreter) {
383 if (bci != InvocationEntryBci) {
384 methodDataOop mdo = m->method_data();
385 if (mdo != NULL) {
386 int count = mdo->bci_to_data(branch_bci)->as_JumpData()->taken();
387 tty->print_cr("back branch count = %d", count);
388 }
389 }
390 }
391 }
392 }
393
394 void NonTieredCompPolicy::trace_osr_request(methodHandle method, nmethod* osr, int bci) {
395 if (TraceOnStackReplacement) {
396 ResourceMark rm;
397 tty->print(osr != NULL ? "Reused OSR entry for " : "Requesting OSR entry for ");
398 method->print_short_name(tty);
399 tty->print_cr(" at bci %d", bci);
400 }
401 }
402 #endif // !PRODUCT
403
404 // SimpleCompPolicy - compile current method
405
406 void SimpleCompPolicy::method_invocation_event( methodHandle m, TRAPS) {
407 int hot_count = m->invocation_count();
408 reset_counter_for_invocation_event(m);
409 const char* comment = "count";
410
411 if (is_compilation_enabled() && can_be_compiled(m)) {
412 nmethod* nm = m->code();
413 if (nm == NULL ) {
414 const char* comment = "count";
415 CompileBroker::compile_method(m, InvocationEntryBci, CompLevel_highest_tier,
416 m, hot_count, comment, CHECK);
417 }
418 }
419 }
420
421 void SimpleCompPolicy::method_back_branch_event(methodHandle m, int bci, TRAPS) {
422 int hot_count = m->backedge_count();
423 const char* comment = "backedge_count";
424
425 if (is_compilation_enabled() && !m->is_not_osr_compilable() && can_be_compiled(m)) {
426 CompileBroker::compile_method(m, bci, CompLevel_highest_tier,
427 m, hot_count, comment, CHECK);
428 NOT_PRODUCT(trace_osr_completion(m->lookup_osr_nmethod_for(bci, CompLevel_highest_tier, true));)
429 }
430 }
431
432 #ifdef COMPILER1
433 bool SimpleProfiledCompPolicy::profile_overflow_event(JavaThread *thread, TRAPS) {
434 RegisterMap map(thread, false);
435 frame fr = thread->last_frame().sender(&map);
436 nmethod* nm = (nmethod*) fr.cb();
437 assert(nm!= NULL && nm->is_nmethod(), "what?");
438 ResourceMark rm;
439
440 vframeStream vfst(thread);
441 methodHandle mh = methodHandle(vfst.method());
442 int bci = vfst.bci();
443
444 bool fix_call = false;
445 {
446 nmethodLocker nml(nm);
447 if (!nm->needs_recomp()) {
448 CounterData* profile = mh->method_data()->bci_to_data(bci)->as_CounterData();
449 bool warm;
450
451 if (is_hot(C1ProfileCompileThreshold, profile->timestamp(), &warm)) {
452
453 assert(mh->method_data() != NULL, "should have a mdo if we get here");
454 nm->set_needs_recomp(true);
455 methodHandle mh_recomp(nm->method());
456
457 if (TraceC1ProfileInlining) {
458 ttyLocker ttyl;
459 tty->print("C1ProfileInlining: recompiling: ");
460 mh_recomp->print_short_name(tty);
461 tty->print(" because of ");
462 mh->print_short_name(tty);
463 tty->print_cr(" at bci = %d", bci);
464 }
465
466 const char* comment = "tier1 overflow";
467 profile->set_hot();
468 CompileBroker::compile_method(mh_recomp, InvocationEntryBci, CompLevel_highest_tier,
469 mh_recomp, C1ProfileCompileThreshold, comment, CHECK_(true));
470 fix_call = true;
471 } else if (warm) {
472 fix_call = true;
473 profile->set_warm();
474 } else {
475 profile->set_cold();
476 }
477 if (!fix_call) {
478 profile->set_count(0);
479 profile->set_timestamp(os::javaTimeNanos());
480 }
481 } else {
482 fix_call = true;
483 }
484 }
485 return fix_call;
486 }
487 #endif
488
489
490 // StackWalkCompPolicy - walk up stack to find a suitable method to compile
491
492 #ifdef COMPILER2
493 const char* StackWalkCompPolicy::_msg = NULL;
494
495
496 // Consider m for compilation
497 void StackWalkCompPolicy::method_invocation_event(methodHandle m, TRAPS) {
498 int hot_count = m->invocation_count();
499 reset_counter_for_invocation_event(m);
500 const char* comment = "count";
501
502 if (is_compilation_enabled() && m->code() == NULL && can_be_compiled(m)) {
503 ResourceMark rm(THREAD);
504 JavaThread *thread = (JavaThread*)THREAD;
505 frame fr = thread->last_frame();
506 assert(fr.is_interpreted_frame(), "must be interpreted");
507 assert(fr.interpreter_frame_method() == m(), "bad method");
508
509 if (TraceCompilationPolicy) {
510 tty->print("method invocation trigger: ");
511 m->print_short_name(tty);
512 tty->print(" ( interpreted " INTPTR_FORMAT ", size=%d ) ", (address)m(), m->code_size());
513 }
514 RegisterMap reg_map(thread, false);
515 javaVFrame* triggerVF = thread->last_java_vframe(®_map);
516 // triggerVF is the frame that triggered its counter
517 RFrame* first = new InterpretedRFrame(triggerVF->fr(), thread, m);
518
519 if (first->top_method()->code() != NULL) {
520 // called obsolete method/nmethod -- no need to recompile
521 if (TraceCompilationPolicy) tty->print_cr(" --> " INTPTR_FORMAT, first->top_method()->code());
522 } else {
523 if (TimeCompilationPolicy) accumulated_time()->start();
524 GrowableArray<RFrame*>* stack = new GrowableArray<RFrame*>(50);
525 stack->push(first);
526 RFrame* top = findTopInlinableFrame(stack);
527 if (TimeCompilationPolicy) accumulated_time()->stop();
528 assert(top != NULL, "findTopInlinableFrame returned null");
529 if (TraceCompilationPolicy) top->print();
530 CompileBroker::compile_method(top->top_method(), InvocationEntryBci, CompLevel_highest_tier,
531 m, hot_count, comment, CHECK);
532 }
533 }
534 }
535
536 void StackWalkCompPolicy::method_back_branch_event(methodHandle m, int bci, TRAPS) {
537 int hot_count = m->backedge_count();
538 const char* comment = "backedge_count";
539
540 if (is_compilation_enabled() && !m->is_not_osr_compilable() && can_be_compiled(m)) {
541 CompileBroker::compile_method(m, bci, CompLevel_highest_tier, m, hot_count, comment, CHECK);
542
543 NOT_PRODUCT(trace_osr_completion(m->lookup_osr_nmethod_for(bci, CompLevel_highest_tier, true));)
544 }
545 }
546
547 RFrame* StackWalkCompPolicy::findTopInlinableFrame(GrowableArray<RFrame*>* stack) {
548 // go up the stack until finding a frame that (probably) won't be inlined
549 // into its caller
550 RFrame* current = stack->at(0); // current choice for stopping
551 assert( current && !current->is_compiled(), "" );
552 const char* msg = NULL;
553
554 while (1) {
555
556 // before going up the stack further, check if doing so would get us into
557 // compiled code
558 RFrame* next = senderOf(current, stack);
559 if( !next ) // No next frame up the stack?
560 break; // Then compile with current frame
561
562 methodHandle m = current->top_method();
563 methodHandle next_m = next->top_method();
564
565 if (TraceCompilationPolicy && Verbose) {
566 tty->print("[caller: ");
567 next_m->print_short_name(tty);
568 tty->print("] ");
569 }
570
571 if( !Inline ) { // Inlining turned off
572 msg = "Inlining turned off";
573 break;
574 }
575 if (next_m->is_not_compilable()) { // Did fail to compile this before/
576 msg = "caller not compilable";
577 break;
578 }
579 if (next->num() > MaxRecompilationSearchLength) {
580 // don't go up too high when searching for recompilees
581 msg = "don't go up any further: > MaxRecompilationSearchLength";
582 break;
583 }
584 if (next->distance() > MaxInterpretedSearchLength) {
585 // don't go up too high when searching for recompilees
586 msg = "don't go up any further: next > MaxInterpretedSearchLength";
587 break;
588 }
589 // Compiled frame above already decided not to inline;
590 // do not recompile him.
591 if (next->is_compiled()) {
592 msg = "not going up into optimized code";
593 break;
594 }
595
596 // Interpreted frame above us was already compiled. Do not force
597 // a recompile, although if the frame above us runs long enough an
598 // OSR might still happen.
599 if( current->is_interpreted() && next_m->has_compiled_code() ) {
600 msg = "not going up -- already compiled caller";
601 break;
602 }
603
604 // Compute how frequent this call site is. We have current method 'm'.
605 // We know next method 'next_m' is interpreted. Find the call site and
606 // check the various invocation counts.
607 int invcnt = 0; // Caller counts
608 if (ProfileInterpreter) {
609 invcnt = next_m->interpreter_invocation_count();
610 }
611 int cnt = 0; // Call site counts
612 if (ProfileInterpreter && next_m->method_data() != NULL) {
613 ResourceMark rm;
614 int bci = next->top_vframe()->bci();
615 ProfileData* data = next_m->method_data()->bci_to_data(bci);
616 if (data != NULL && data->is_CounterData())
617 cnt = data->as_CounterData()->count();
618 }
619
620 // Caller counts / call-site counts; i.e. is this call site
621 // a hot call site for method next_m?
622 int freq = (invcnt) ? cnt/invcnt : cnt;
623
624 // Check size and frequency limits
625 if ((msg = shouldInline(m, freq, cnt)) != NULL) {
626 break;
627 }
628 // Check inlining negative tests
629 if ((msg = shouldNotInline(m)) != NULL) {
630 break;
631 }
632
633
634 // If the caller method is too big or something then we do not want to
635 // compile it just to inline a method
636 if (!can_be_compiled(next_m)) {
637 msg = "caller cannot be compiled";
638 break;
639 }
640
641 if( next_m->name() == vmSymbols::class_initializer_name() ) {
642 msg = "do not compile class initializer (OSR ok)";
643 break;
644 }
645
646 if (TraceCompilationPolicy && Verbose) {
647 tty->print("\n\t check caller: ");
648 next_m->print_short_name(tty);
649 tty->print(" ( interpreted " INTPTR_FORMAT ", size=%d ) ", (address)next_m(), next_m->code_size());
650 }
651
652 current = next;
653 }
654
655 assert( !current || !current->is_compiled(), "" );
656
657 if (TraceCompilationPolicy && msg) tty->print("(%s)\n", msg);
658
659 return current;
660 }
661
662 RFrame* StackWalkCompPolicy::senderOf(RFrame* rf, GrowableArray<RFrame*>* stack) {
663 RFrame* sender = rf->caller();
664 if (sender && sender->num() == stack->length()) stack->push(sender);
665 return sender;
666 }
667
668
669 const char* StackWalkCompPolicy::shouldInline(methodHandle m, float freq, int cnt) {
670 // Allows targeted inlining
671 // positive filter: should send be inlined? returns NULL (--> yes)
672 // or rejection msg
673 int max_size = MaxInlineSize;
674 int cost = m->code_size();
675
676 // Check for too many throws (and not too huge)
677 if (m->interpreter_throwout_count() > InlineThrowCount && cost < InlineThrowMaxSize ) {
678 return NULL;
679 }
680
681 // bump the max size if the call is frequent
682 if ((freq >= InlineFrequencyRatio) || (cnt >= InlineFrequencyCount)) {
683 if (TraceFrequencyInlining) {
684 tty->print("(Inlined frequent method)\n");
685 m->print();
686 }
687 max_size = FreqInlineSize;
688 }
689 if (cost > max_size) {
690 return (_msg = "too big");
691 }
692 return NULL;
693 }
694
695
696 const char* StackWalkCompPolicy::shouldNotInline(methodHandle m) {
697 // negative filter: should send NOT be inlined? returns NULL (--> inline) or rejection msg
698 if (m->is_abstract()) return (_msg = "abstract method");
699 // note: we allow ik->is_abstract()
700 if (!instanceKlass::cast(m->method_holder())->is_initialized()) return (_msg = "method holder not initialized");
701 if (m->is_native()) return (_msg = "native method");
702 nmethod* m_code = m->code();
703 if (m_code != NULL && m_code->code_size() > InlineSmallCode)
704 return (_msg = "already compiled into a big method");
705
706 // use frequency-based objections only for non-trivial methods
707 if (m->code_size() <= MaxTrivialSize) return NULL;
708 if (UseInterpreter) { // don't use counts with -Xcomp
709 if ((m->code() == NULL) && m->was_never_executed()) return (_msg = "never executed");
710 if (!m->was_executed_more_than(MIN2(MinInliningThreshold, CompileThreshold >> 1))) return (_msg = "executed < MinInliningThreshold times");
711 }
712 if (methodOopDesc::has_unloaded_classes_in_signature(m, JavaThread::current())) return (_msg = "unloaded signature classes");
713
714 return NULL;
715 }
716
717
718
719 #endif // COMPILER2