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