1 /*
2 * Copyright (c) 2000, 2018, 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 "classfile/classLoaderData.inline.hpp"
27 #include "code/compiledIC.hpp"
28 #include "code/nmethod.hpp"
29 #include "code/scopeDesc.hpp"
30 #include "interpreter/interpreter.hpp"
31 #include "memory/resourceArea.hpp"
32 #include "oops/methodData.hpp"
33 #include "oops/method.hpp"
34 #include "oops/oop.inline.hpp"
35 #include "prims/nativeLookup.hpp"
36 #include "runtime/advancedThresholdPolicy.hpp"
37 #include "runtime/compilationPolicy.hpp"
38 #include "runtime/frame.hpp"
39 #include "runtime/handles.inline.hpp"
40 #include "runtime/rframe.hpp"
41 #include "runtime/simpleThresholdPolicy.hpp"
42 #include "runtime/stubRoutines.hpp"
43 #include "runtime/thread.hpp"
44 #include "runtime/timer.hpp"
45 #include "runtime/vframe.hpp"
46 #include "runtime/vm_operations.hpp"
47 #include "utilities/events.hpp"
48 #include "utilities/globalDefinitions.hpp"
49
50 CompilationPolicy* CompilationPolicy::_policy;
51 elapsedTimer CompilationPolicy::_accumulated_time;
52 bool CompilationPolicy::_in_vm_startup;
53
54 // Determine compilation policy based on command line argument
55 void compilationPolicy_init() {
56 CompilationPolicy::set_in_vm_startup(DelayCompilationDuringStartup);
57
58 switch(CompilationPolicyChoice) {
59 case 0:
60 CompilationPolicy::set_policy(new SimpleCompPolicy());
61 break;
62
63 case 1:
64 #ifdef COMPILER2
65 CompilationPolicy::set_policy(new StackWalkCompPolicy());
66 #else
67 Unimplemented();
68 #endif
69 break;
70 case 2:
71 #ifdef TIERED
72 CompilationPolicy::set_policy(new SimpleThresholdPolicy());
73 #else
74 Unimplemented();
75 #endif
76 break;
77 case 3:
78 #ifdef TIERED
79 CompilationPolicy::set_policy(new AdvancedThresholdPolicy());
80 #else
81 Unimplemented();
82 #endif
83 break;
84 default:
85 fatal("CompilationPolicyChoice must be in the range: [0-3]");
86 }
87 CompilationPolicy::policy()->initialize();
88 }
89
90 void CompilationPolicy::completed_vm_startup() {
91 if (TraceCompilationPolicy) {
92 tty->print("CompilationPolicy: completed vm startup.\n");
93 }
94 _in_vm_startup = false;
95 }
96
97 // Returns true if m must be compiled before executing it
98 // This is intended to force compiles for methods (usually for
99 // debugging) that would otherwise be interpreted for some reason.
100 bool CompilationPolicy::must_be_compiled(const methodHandle& m, int comp_level) {
101 // Don't allow Xcomp to cause compiles in replay mode
102 if (ReplayCompiles) return false;
103
104 if (m->has_compiled_code()) return false; // already compiled
105 if (!can_be_compiled(m, comp_level)) return false;
106
107 return !UseInterpreter || // must compile all methods
108 (UseCompiler && AlwaysCompileLoopMethods && m->has_loops() && CompileBroker::should_compile_new_jobs()); // eagerly compile loop methods
109 }
110
111 void CompilationPolicy::compile_if_required(const methodHandle& selected_method, TRAPS) {
112 if (must_be_compiled(selected_method)) {
113 // This path is unusual, mostly used by the '-Xcomp' stress test mode.
114
115 // Note: with several active threads, the must_be_compiled may be true
116 // while can_be_compiled is false; remove assert
117 // assert(CompilationPolicy::can_be_compiled(selected_method), "cannot compile");
118 if (!THREAD->can_call_java() || THREAD->is_Compiler_thread()) {
119 // don't force compilation, resolve was on behalf of compiler
120 return;
121 }
122 if (selected_method->method_holder()->is_not_initialized()) {
123 // 'is_not_initialized' means not only '!is_initialized', but also that
124 // initialization has not been started yet ('!being_initialized')
125 // Do not force compilation of methods in uninitialized classes.
126 // Note that doing this would throw an assert later,
127 // in CompileBroker::compile_method.
128 // We sometimes use the link resolver to do reflective lookups
129 // even before classes are initialized.
130 return;
131 }
132 CompileBroker::compile_method(selected_method, InvocationEntryBci,
133 CompilationPolicy::policy()->initial_compile_level(),
134 methodHandle(), 0, CompileTask::Reason_MustBeCompiled, CHECK);
135 }
136 }
137
138 // Returns true if m is allowed to be compiled
139 bool CompilationPolicy::can_be_compiled(const methodHandle& m, int comp_level) {
140 // allow any levels for WhiteBox
141 assert(WhiteBoxAPI || comp_level == CompLevel_all || is_compile(comp_level), "illegal compilation level");
142
143 if (m->is_abstract()) return false;
144 if (DontCompileHugeMethods && m->code_size() > HugeMethodLimit) return false;
145
146 // Math intrinsics should never be compiled as this can lead to
147 // monotonicity problems because the interpreter will prefer the
148 // compiled code to the intrinsic version. This can't happen in
149 // production because the invocation counter can't be incremented
150 // but we shouldn't expose the system to this problem in testing
151 // modes.
152 if (!AbstractInterpreter::can_be_compiled(m)) {
153 return false;
154 }
155 if (comp_level == CompLevel_all) {
156 if (TieredCompilation) {
157 // enough to be compilable at any level for tiered
158 return !m->is_not_compilable(CompLevel_simple) || !m->is_not_compilable(CompLevel_full_optimization);
159 } else {
160 // must be compilable at available level for non-tiered
161 return !m->is_not_compilable(CompLevel_highest_tier);
162 }
163 } else if (is_compile(comp_level)) {
164 return !m->is_not_compilable(comp_level);
165 }
166 return false;
167 }
168
169 // Returns true if m is allowed to be osr compiled
170 bool CompilationPolicy::can_be_osr_compiled(const methodHandle& m, int comp_level) {
171 bool result = false;
172 if (comp_level == CompLevel_all) {
173 if (TieredCompilation) {
174 // enough to be osr compilable at any level for tiered
175 result = !m->is_not_osr_compilable(CompLevel_simple) || !m->is_not_osr_compilable(CompLevel_full_optimization);
176 } else {
177 // must be osr compilable at available level for non-tiered
178 result = !m->is_not_osr_compilable(CompLevel_highest_tier);
179 }
180 } else if (is_compile(comp_level)) {
181 result = !m->is_not_osr_compilable(comp_level);
182 }
183 return (result && can_be_compiled(m, comp_level));
184 }
185
186 bool CompilationPolicy::is_compilation_enabled() {
187 // NOTE: CompileBroker::should_compile_new_jobs() checks for UseCompiler
188 return !delay_compilation_during_startup() && CompileBroker::should_compile_new_jobs();
189 }
190
191 CompileTask* CompilationPolicy::select_task_helper(CompileQueue* compile_queue) {
192 #if INCLUDE_JVMCI
193 if (UseJVMCICompiler && !BackgroundCompilation) {
194 /*
195 * In blocking compilation mode, the CompileBroker will make
196 * compilations submitted by a JVMCI compiler thread non-blocking. These
197 * compilations should be scheduled after all blocking compilations
198 * to service non-compiler related compilations sooner and reduce the
199 * chance of such compilations timing out.
200 */
201 for (CompileTask* task = compile_queue->first(); task != NULL; task = task->next()) {
202 if (task->is_blocking()) {
203 return task;
204 }
205 }
206 }
207 #endif
208 return compile_queue->first();
209 }
210
211 #ifndef PRODUCT
212 void CompilationPolicy::print_time() {
213 tty->print_cr ("Accumulated compilationPolicy times:");
214 tty->print_cr ("---------------------------");
215 tty->print_cr (" Total: %3.3f sec.", _accumulated_time.seconds());
216 }
217
218 void NonTieredCompPolicy::trace_osr_completion(nmethod* osr_nm) {
219 if (TraceOnStackReplacement) {
220 if (osr_nm == NULL) tty->print_cr("compilation failed");
221 else tty->print_cr("nmethod " INTPTR_FORMAT, p2i(osr_nm));
222 }
223 }
224 #endif // !PRODUCT
225
226 void NonTieredCompPolicy::initialize() {
227 // Setup the compiler thread numbers
228 if (CICompilerCountPerCPU) {
229 // Example: if CICompilerCountPerCPU is true, then we get
230 // max(log2(8)-1,1) = 2 compiler threads on an 8-way machine.
231 // May help big-app startup time.
232 _compiler_count = MAX2(log2_intptr(os::active_processor_count())-1,1);
233 FLAG_SET_ERGO(intx, CICompilerCount, _compiler_count);
234 } else {
235 _compiler_count = CICompilerCount;
236 }
237 }
238
239 // Note: this policy is used ONLY if TieredCompilation is off.
240 // compiler_count() behaves the following way:
241 // - with TIERED build (with both COMPILER1 and COMPILER2 defined) it should return
242 // zero for the c1 compilation levels in server compilation mode runs
243 // and c2 compilation levels in client compilation mode runs.
244 // - with COMPILER2 not defined it should return zero for c2 compilation levels.
245 // - with COMPILER1 not defined it should return zero for c1 compilation levels.
246 // - if neither is defined - always return zero.
247 int NonTieredCompPolicy::compiler_count(CompLevel comp_level) {
248 assert(!TieredCompilation, "This policy should not be used with TieredCompilation");
249 if (COMPILER2_PRESENT(is_server_compilation_mode_vm() && is_c2_compile(comp_level) ||)
250 is_client_compilation_mode_vm() && is_c1_compile(comp_level)) {
251 return _compiler_count;
252 }
253 return 0;
254 }
255
256 void NonTieredCompPolicy::reset_counter_for_invocation_event(const methodHandle& m) {
257 // Make sure invocation and backedge counter doesn't overflow again right away
258 // as would be the case for native methods.
259
260 // BUT also make sure the method doesn't look like it was never executed.
261 // Set carry bit and reduce counter's value to min(count, CompileThreshold/2).
262 MethodCounters* mcs = m->method_counters();
263 assert(mcs != NULL, "MethodCounters cannot be NULL for profiling");
264 mcs->invocation_counter()->set_carry();
265 mcs->backedge_counter()->set_carry();
266
267 assert(!m->was_never_executed(), "don't reset to 0 -- could be mistaken for never-executed");
268 }
269
270 void NonTieredCompPolicy::reset_counter_for_back_branch_event(const methodHandle& m) {
271 // Delay next back-branch event but pump up invocation counter to trigger
272 // whole method compilation.
273 MethodCounters* mcs = m->method_counters();
274 assert(mcs != NULL, "MethodCounters cannot be NULL for profiling");
275 InvocationCounter* i = mcs->invocation_counter();
276 InvocationCounter* b = mcs->backedge_counter();
277
278 // Don't set invocation_counter's value too low otherwise the method will
279 // look like immature (ic < ~5300) which prevents the inlining based on
280 // the type profiling.
281 i->set(i->state(), CompileThreshold);
282 // Don't reset counter too low - it is used to check if OSR method is ready.
283 b->set(b->state(), CompileThreshold / 2);
284 }
285
286 //
287 // CounterDecay
288 //
289 // Iterates through invocation counters and decrements them. This
290 // is done at each safepoint.
291 //
292 class CounterDecay : public AllStatic {
293 static jlong _last_timestamp;
294 static void do_method(Method* m) {
295 MethodCounters* mcs = m->method_counters();
296 if (mcs != NULL) {
297 mcs->invocation_counter()->decay();
298 }
299 }
300 public:
301 static void decay();
302 static bool is_decay_needed() {
303 return (os::javaTimeMillis() - _last_timestamp) > CounterDecayMinIntervalLength;
304 }
305 };
306
307 jlong CounterDecay::_last_timestamp = 0;
308
309 void CounterDecay::decay() {
310 _last_timestamp = os::javaTimeMillis();
311
312 // This operation is going to be performed only at the end of a safepoint
313 // and hence GC's will not be going on, all Java mutators are suspended
314 // at this point and hence SystemDictionary_lock is also not needed.
315 assert(SafepointSynchronize::is_at_safepoint(), "can only be executed at a safepoint");
316 size_t nclasses = ClassLoaderDataGraph::num_instance_classes();
317 size_t classes_per_tick = nclasses * (CounterDecayMinIntervalLength * 1e-3 /
318 CounterHalfLifeTime);
319 for (size_t i = 0; i < classes_per_tick; i++) {
320 InstanceKlass* k = ClassLoaderDataGraph::try_get_next_class();
321 if (k != NULL) {
322 k->methods_do(do_method);
323 }
324 }
325 }
326
327 // Called at the end of the safepoint
328 void NonTieredCompPolicy::do_safepoint_work() {
329 if(UseCounterDecay && CounterDecay::is_decay_needed()) {
330 CounterDecay::decay();
331 }
332 }
333
334 void NonTieredCompPolicy::reprofile(ScopeDesc* trap_scope, bool is_osr) {
335 ScopeDesc* sd = trap_scope;
336 MethodCounters* mcs;
337 InvocationCounter* c;
338 for (; !sd->is_top(); sd = sd->sender()) {
339 mcs = sd->method()->method_counters();
340 if (mcs != NULL) {
341 // Reset ICs of inlined methods, since they can trigger compilations also.
342 mcs->invocation_counter()->reset();
343 }
344 }
345 mcs = sd->method()->method_counters();
346 if (mcs != NULL) {
347 c = mcs->invocation_counter();
348 if (is_osr) {
349 // It was an OSR method, so bump the count higher.
350 c->set(c->state(), CompileThreshold);
351 } else {
352 c->reset();
353 }
354 mcs->backedge_counter()->reset();
355 }
356 }
357
358 // This method can be called by any component of the runtime to notify the policy
359 // that it's recommended to delay the compilation of this method.
360 void NonTieredCompPolicy::delay_compilation(Method* method) {
361 MethodCounters* mcs = method->method_counters();
362 if (mcs != NULL) {
363 mcs->invocation_counter()->decay();
364 mcs->backedge_counter()->decay();
365 }
366 }
367
368 void NonTieredCompPolicy::disable_compilation(Method* method) {
369 MethodCounters* mcs = method->method_counters();
370 if (mcs != NULL) {
371 mcs->invocation_counter()->set_state(InvocationCounter::wait_for_nothing);
372 mcs->backedge_counter()->set_state(InvocationCounter::wait_for_nothing);
373 }
374 }
375
376 CompileTask* NonTieredCompPolicy::select_task(CompileQueue* compile_queue) {
377 return select_task_helper(compile_queue);
378 }
379
380 bool NonTieredCompPolicy::is_mature(Method* method) {
381 MethodData* mdo = method->method_data();
382 assert(mdo != NULL, "Should be");
383 uint current = mdo->mileage_of(method);
384 uint initial = mdo->creation_mileage();
385 if (current < initial)
386 return true; // some sort of overflow
387 uint target;
388 if (ProfileMaturityPercentage <= 0)
389 target = (uint) -ProfileMaturityPercentage; // absolute value
390 else
391 target = (uint)( (ProfileMaturityPercentage * CompileThreshold) / 100 );
392 return (current >= initial + target);
393 }
394
395 nmethod* NonTieredCompPolicy::event(const methodHandle& method, const methodHandle& inlinee, int branch_bci,
396 int bci, CompLevel comp_level, CompiledMethod* nm, JavaThread* thread) {
397 assert(comp_level == CompLevel_none, "This should be only called from the interpreter");
398 NOT_PRODUCT(trace_frequency_counter_overflow(method, branch_bci, bci));
399 if (JvmtiExport::can_post_interpreter_events() && thread->is_interp_only_mode()) {
400 // If certain JVMTI events (e.g. frame pop event) are requested then the
401 // thread is forced to remain in interpreted code. This is
402 // implemented partly by a check in the run_compiled_code
403 // section of the interpreter whether we should skip running
404 // compiled code, and partly by skipping OSR compiles for
405 // interpreted-only threads.
406 if (bci != InvocationEntryBci) {
407 reset_counter_for_back_branch_event(method);
408 return NULL;
409 }
410 }
411 if (CompileTheWorld || ReplayCompiles) {
412 // Don't trigger other compiles in testing mode
413 if (bci == InvocationEntryBci) {
414 reset_counter_for_invocation_event(method);
415 } else {
416 reset_counter_for_back_branch_event(method);
417 }
418 return NULL;
419 }
420
421 if (bci == InvocationEntryBci) {
422 // when code cache is full, compilation gets switched off, UseCompiler
423 // is set to false
424 if (!method->has_compiled_code() && UseCompiler) {
425 method_invocation_event(method, thread);
426 } else {
427 // Force counter overflow on method entry, even if no compilation
428 // happened. (The method_invocation_event call does this also.)
429 reset_counter_for_invocation_event(method);
430 }
431 // compilation at an invocation overflow no longer goes and retries test for
432 // compiled method. We always run the loser of the race as interpreted.
433 // so return NULL
434 return NULL;
435 } else {
436 // counter overflow in a loop => try to do on-stack-replacement
437 nmethod* osr_nm = method->lookup_osr_nmethod_for(bci, CompLevel_highest_tier, true);
438 NOT_PRODUCT(trace_osr_request(method, osr_nm, bci));
439 // when code cache is full, we should not compile any more...
440 if (osr_nm == NULL && UseCompiler) {
441 method_back_branch_event(method, bci, thread);
442 osr_nm = method->lookup_osr_nmethod_for(bci, CompLevel_highest_tier, true);
443 }
444 if (osr_nm == NULL) {
445 reset_counter_for_back_branch_event(method);
446 return NULL;
447 }
448 return osr_nm;
449 }
450 return NULL;
451 }
452
453 #ifndef PRODUCT
454 void NonTieredCompPolicy::trace_frequency_counter_overflow(const methodHandle& m, int branch_bci, int bci) {
455 if (TraceInvocationCounterOverflow) {
456 MethodCounters* mcs = m->method_counters();
457 assert(mcs != NULL, "MethodCounters cannot be NULL for profiling");
458 InvocationCounter* ic = mcs->invocation_counter();
459 InvocationCounter* bc = mcs->backedge_counter();
460 ResourceMark rm;
461 if (bci == InvocationEntryBci) {
462 tty->print("comp-policy cntr ovfl @ %d in entry of ", bci);
463 } else {
464 tty->print("comp-policy cntr ovfl @ %d in loop of ", bci);
465 }
466 m->print_value();
467 tty->cr();
468 ic->print();
469 bc->print();
470 if (ProfileInterpreter) {
471 if (bci != InvocationEntryBci) {
472 MethodData* mdo = m->method_data();
473 if (mdo != NULL) {
474 ProfileData *pd = mdo->bci_to_data(branch_bci);
475 if (pd == NULL) {
476 tty->print_cr("back branch count = N/A (missing ProfileData)");
477 } else {
478 tty->print_cr("back branch count = %d", pd->as_JumpData()->taken());
479 }
480 }
481 }
482 }
483 }
484 }
485
486 void NonTieredCompPolicy::trace_osr_request(const methodHandle& method, nmethod* osr, int bci) {
487 if (TraceOnStackReplacement) {
488 ResourceMark rm;
489 tty->print(osr != NULL ? "Reused OSR entry for " : "Requesting OSR entry for ");
490 method->print_short_name(tty);
491 tty->print_cr(" at bci %d", bci);
492 }
493 }
494 #endif // !PRODUCT
495
496 // SimpleCompPolicy - compile current method
497
498 void SimpleCompPolicy::method_invocation_event(const methodHandle& m, JavaThread* thread) {
499 const int comp_level = CompLevel_highest_tier;
500 const int hot_count = m->invocation_count();
501 reset_counter_for_invocation_event(m);
502
503 if (is_compilation_enabled() && can_be_compiled(m, comp_level)) {
504 CompiledMethod* nm = m->code();
505 if (nm == NULL ) {
506 CompileBroker::compile_method(m, InvocationEntryBci, comp_level, m, hot_count, CompileTask::Reason_InvocationCount, thread);
507 }
508 }
509 }
510
511 void SimpleCompPolicy::method_back_branch_event(const methodHandle& m, int bci, JavaThread* thread) {
512 const int comp_level = CompLevel_highest_tier;
513 const int hot_count = m->backedge_count();
514
515 if (is_compilation_enabled() && can_be_osr_compiled(m, comp_level)) {
516 CompileBroker::compile_method(m, bci, comp_level, m, hot_count, CompileTask::Reason_BackedgeCount, thread);
517 NOT_PRODUCT(trace_osr_completion(m->lookup_osr_nmethod_for(bci, comp_level, true));)
518 }
519 }
520 // StackWalkCompPolicy - walk up stack to find a suitable method to compile
521
522 #ifdef COMPILER2
523 const char* StackWalkCompPolicy::_msg = NULL;
524
525
526 // Consider m for compilation
527 void StackWalkCompPolicy::method_invocation_event(const methodHandle& m, JavaThread* thread) {
528 const int comp_level = CompLevel_highest_tier;
529 const int hot_count = m->invocation_count();
530 reset_counter_for_invocation_event(m);
531
532 if (is_compilation_enabled() && m->code() == NULL && can_be_compiled(m, comp_level)) {
533 ResourceMark rm(thread);
534 frame fr = thread->last_frame();
535 assert(fr.is_interpreted_frame(), "must be interpreted");
536 assert(fr.interpreter_frame_method() == m(), "bad method");
537
538 if (TraceCompilationPolicy) {
539 tty->print("method invocation trigger: ");
540 m->print_short_name(tty);
541 tty->print(" ( interpreted " INTPTR_FORMAT ", size=%d ) ", p2i((address)m()), m->code_size());
542 }
543 RegisterMap reg_map(thread, false);
544 javaVFrame* triggerVF = thread->last_java_vframe(®_map);
545 // triggerVF is the frame that triggered its counter
546 RFrame* first = new InterpretedRFrame(triggerVF->fr(), thread, m());
547
548 if (first->top_method()->code() != NULL) {
549 // called obsolete method/nmethod -- no need to recompile
550 if (TraceCompilationPolicy) tty->print_cr(" --> " INTPTR_FORMAT, p2i(first->top_method()->code()));
551 } else {
552 if (TimeCompilationPolicy) accumulated_time()->start();
553 GrowableArray<RFrame*>* stack = new GrowableArray<RFrame*>(50);
554 stack->push(first);
555 RFrame* top = findTopInlinableFrame(stack);
556 if (TimeCompilationPolicy) accumulated_time()->stop();
557 assert(top != NULL, "findTopInlinableFrame returned null");
558 if (TraceCompilationPolicy) top->print();
559 CompileBroker::compile_method(top->top_method(), InvocationEntryBci, comp_level,
560 m, hot_count, CompileTask::Reason_InvocationCount, thread);
561 }
562 }
563 }
564
565 void StackWalkCompPolicy::method_back_branch_event(const methodHandle& m, int bci, JavaThread* thread) {
566 const int comp_level = CompLevel_highest_tier;
567 const int hot_count = m->backedge_count();
568
569 if (is_compilation_enabled() && can_be_osr_compiled(m, comp_level)) {
570 CompileBroker::compile_method(m, bci, comp_level, m, hot_count, CompileTask::Reason_BackedgeCount, thread);
571 NOT_PRODUCT(trace_osr_completion(m->lookup_osr_nmethod_for(bci, comp_level, true));)
572 }
573 }
574
575 RFrame* StackWalkCompPolicy::findTopInlinableFrame(GrowableArray<RFrame*>* stack) {
576 // go up the stack until finding a frame that (probably) won't be inlined
577 // into its caller
578 RFrame* current = stack->at(0); // current choice for stopping
579 assert( current && !current->is_compiled(), "" );
580 const char* msg = NULL;
581
582 while (1) {
583
584 // before going up the stack further, check if doing so would get us into
585 // compiled code
586 RFrame* next = senderOf(current, stack);
587 if( !next ) // No next frame up the stack?
588 break; // Then compile with current frame
589
590 Method* m = current->top_method();
591 Method* next_m = next->top_method();
592
593 if (TraceCompilationPolicy && Verbose) {
594 tty->print("[caller: ");
595 next_m->print_short_name(tty);
596 tty->print("] ");
597 }
598
599 if( !Inline ) { // Inlining turned off
600 msg = "Inlining turned off";
601 break;
602 }
603 if (next_m->is_not_compilable()) { // Did fail to compile this before/
604 msg = "caller not compilable";
605 break;
606 }
607 if (next->num() > MaxRecompilationSearchLength) {
608 // don't go up too high when searching for recompilees
609 msg = "don't go up any further: > MaxRecompilationSearchLength";
610 break;
611 }
612 if (next->distance() > MaxInterpretedSearchLength) {
613 // don't go up too high when searching for recompilees
614 msg = "don't go up any further: next > MaxInterpretedSearchLength";
615 break;
616 }
617 // Compiled frame above already decided not to inline;
618 // do not recompile him.
619 if (next->is_compiled()) {
620 msg = "not going up into optimized code";
621 break;
622 }
623
624 // Interpreted frame above us was already compiled. Do not force
625 // a recompile, although if the frame above us runs long enough an
626 // OSR might still happen.
627 if( current->is_interpreted() && next_m->has_compiled_code() ) {
628 msg = "not going up -- already compiled caller";
629 break;
630 }
631
632 // Compute how frequent this call site is. We have current method 'm'.
633 // We know next method 'next_m' is interpreted. Find the call site and
634 // check the various invocation counts.
635 int invcnt = 0; // Caller counts
636 if (ProfileInterpreter) {
637 invcnt = next_m->interpreter_invocation_count();
638 }
639 int cnt = 0; // Call site counts
640 if (ProfileInterpreter && next_m->method_data() != NULL) {
641 ResourceMark rm;
642 int bci = next->top_vframe()->bci();
643 ProfileData* data = next_m->method_data()->bci_to_data(bci);
644 if (data != NULL && data->is_CounterData())
645 cnt = data->as_CounterData()->count();
646 }
647
648 // Caller counts / call-site counts; i.e. is this call site
649 // a hot call site for method next_m?
650 int freq = (invcnt) ? cnt/invcnt : cnt;
651
652 // Check size and frequency limits
653 if ((msg = shouldInline(m, freq, cnt)) != NULL) {
654 break;
655 }
656 // Check inlining negative tests
657 if ((msg = shouldNotInline(m)) != NULL) {
658 break;
659 }
660
661
662 // If the caller method is too big or something then we do not want to
663 // compile it just to inline a method
664 if (!can_be_compiled(next_m, CompLevel_any)) {
665 msg = "caller cannot be compiled";
666 break;
667 }
668
669 if( next_m->name() == vmSymbols::class_initializer_name() ) {
670 msg = "do not compile class initializer (OSR ok)";
671 break;
672 }
673
674 if (TraceCompilationPolicy && Verbose) {
675 tty->print("\n\t check caller: ");
676 next_m->print_short_name(tty);
677 tty->print(" ( interpreted " INTPTR_FORMAT ", size=%d ) ", p2i((address)next_m), next_m->code_size());
678 }
679
680 current = next;
681 }
682
683 assert( !current || !current->is_compiled(), "" );
684
685 if (TraceCompilationPolicy && msg) tty->print("(%s)\n", msg);
686
687 return current;
688 }
689
690 RFrame* StackWalkCompPolicy::senderOf(RFrame* rf, GrowableArray<RFrame*>* stack) {
691 RFrame* sender = rf->caller();
692 if (sender && sender->num() == stack->length()) stack->push(sender);
693 return sender;
694 }
695
696
697 const char* StackWalkCompPolicy::shouldInline(const methodHandle& m, float freq, int cnt) {
698 // Allows targeted inlining
699 // positive filter: should send be inlined? returns NULL (--> yes)
700 // or rejection msg
701 int max_size = MaxInlineSize;
702 int cost = m->code_size();
703
704 // Check for too many throws (and not too huge)
705 if (m->interpreter_throwout_count() > InlineThrowCount && cost < InlineThrowMaxSize ) {
706 return NULL;
707 }
708
709 // bump the max size if the call is frequent
710 if ((freq >= InlineFrequencyRatio) || (cnt >= InlineFrequencyCount)) {
711 if (TraceFrequencyInlining) {
712 tty->print("(Inlined frequent method)\n");
713 m->print();
714 }
715 max_size = FreqInlineSize;
716 }
717 if (cost > max_size) {
718 return (_msg = "too big");
719 }
720 return NULL;
721 }
722
723
724 const char* StackWalkCompPolicy::shouldNotInline(const methodHandle& m) {
725 // negative filter: should send NOT be inlined? returns NULL (--> inline) or rejection msg
726 if (m->is_abstract()) return (_msg = "abstract method");
727 // note: we allow ik->is_abstract()
728 if (!m->method_holder()->is_initialized()) return (_msg = "method holder not initialized");
729 if (m->is_native()) return (_msg = "native method");
730 CompiledMethod* m_code = m->code();
731 if (m_code != NULL && m_code->code_size() > InlineSmallCode)
732 return (_msg = "already compiled into a big method");
733
734 // use frequency-based objections only for non-trivial methods
735 if (m->code_size() <= MaxTrivialSize) return NULL;
736 if (UseInterpreter) { // don't use counts with -Xcomp
737 if ((m->code() == NULL) && m->was_never_executed()) return (_msg = "never executed");
738 if (!m->was_executed_more_than(MIN2(MinInliningThreshold, CompileThreshold >> 1))) return (_msg = "executed < MinInliningThreshold times");
739 }
740 if (Method::has_unloaded_classes_in_signature(m, JavaThread::current())) return (_msg = "unloaded signature classes");
741
742 return NULL;
743 }
744
745
746
747 #endif // COMPILER2