1 /*
2 * Copyright (c) 2000, 2019, 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/vframe.hpp"
44 #include "runtime/vmOperations.hpp"
45 #include "utilities/events.hpp"
46 #include "utilities/globalDefinitions.hpp"
47
48 #ifdef COMPILER1
49 #include "c1/c1_Compiler.hpp"
50 #endif
51 #ifdef COMPILER2
52 #include "opto/c2compiler.hpp"
53 #endif
54
55 CompilationPolicy* CompilationPolicy::_policy;
56
57 // Determine compilation policy based on command line argument
58 void compilationPolicy_init() {
59 switch(CompilationPolicyChoice) {
60 case 0:
61 CompilationPolicy::set_policy(new SimpleCompPolicy());
62 break;
63
64 case 1:
65 #ifdef COMPILER2
66 CompilationPolicy::set_policy(new StackWalkCompPolicy());
67 #else
68 Unimplemented();
69 #endif
70 break;
71 case 2:
72 #ifdef TIERED
73 CompilationPolicy::set_policy(new TieredThresholdPolicy());
74 #else
75 Unimplemented();
76 #endif
77 break;
78 default:
79 fatal("CompilationPolicyChoice must be in the range: [0-2]");
80 }
81 CompilationPolicy::policy()->initialize();
82 }
83
84 // Returns true if m must be compiled before executing it
85 // This is intended to force compiles for methods (usually for
86 // debugging) that would otherwise be interpreted for some reason.
87 bool CompilationPolicy::must_be_compiled(const methodHandle& m, int comp_level) {
88 // Don't allow Xcomp to cause compiles in replay mode
89 if (ReplayCompiles) return false;
90
91 if (m->has_compiled_code()) return false; // already compiled
92 if (!can_be_compiled(m, comp_level)) return false;
93
94 return !UseInterpreter || // must compile all methods
95 (UseCompiler && AlwaysCompileLoopMethods && m->has_loops() && CompileBroker::should_compile_new_jobs()); // eagerly compile loop methods
96 }
97
98 void CompilationPolicy::compile_if_required(const methodHandle& selected_method, TRAPS) {
99 if (must_be_compiled(selected_method)) {
100 // This path is unusual, mostly used by the '-Xcomp' stress test mode.
101
102 // Note: with several active threads, the must_be_compiled may be true
103 // while can_be_compiled is false; remove assert
104 // assert(CompilationPolicy::can_be_compiled(selected_method), "cannot compile");
105 if (!THREAD->can_call_java() || THREAD->is_Compiler_thread()) {
106 // don't force compilation, resolve was on behalf of compiler
107 return;
108 }
109 if (selected_method->method_holder()->is_not_initialized()) {
110 // 'is_not_initialized' means not only '!is_initialized', but also that
111 // initialization has not been started yet ('!being_initialized')
112 // Do not force compilation of methods in uninitialized classes.
113 // Note that doing this would throw an assert later,
114 // in CompileBroker::compile_method.
115 // We sometimes use the link resolver to do reflective lookups
116 // even before classes are initialized.
117 return;
118 }
119 CompileBroker::compile_method(selected_method, InvocationEntryBci,
120 CompilationPolicy::policy()->initial_compile_level(),
121 methodHandle(), 0, CompileTask::Reason_MustBeCompiled, CHECK);
122 }
123 }
124
125 // Returns true if m is allowed to be compiled
126 bool CompilationPolicy::can_be_compiled(const methodHandle& m, int comp_level) {
127 // allow any levels for WhiteBox
128 assert(WhiteBoxAPI || comp_level == CompLevel_all || is_compile(comp_level), "illegal compilation level");
129
130 if (m->is_abstract()) return false;
131 if (DontCompileHugeMethods && m->code_size() > HugeMethodLimit) return false;
132
133 // Math intrinsics should never be compiled as this can lead to
134 // monotonicity problems because the interpreter will prefer the
135 // compiled code to the intrinsic version. This can't happen in
136 // production because the invocation counter can't be incremented
137 // but we shouldn't expose the system to this problem in testing
138 // modes.
139 if (!AbstractInterpreter::can_be_compiled(m)) {
140 return false;
141 }
142 if (comp_level == CompLevel_all) {
143 if (TieredCompilation) {
144 // enough to be compilable at any level for tiered
145 return !m->is_not_compilable(CompLevel_simple) || !m->is_not_compilable(CompLevel_full_optimization);
146 } else {
147 // must be compilable at available level for non-tiered
148 return !m->is_not_compilable(CompLevel_highest_tier);
149 }
150 } else if (is_compile(comp_level)) {
151 return !m->is_not_compilable(comp_level);
152 }
153 return false;
154 }
155
156 // Returns true if m is allowed to be osr compiled
157 bool CompilationPolicy::can_be_osr_compiled(const methodHandle& m, int comp_level) {
158 bool result = false;
159 if (comp_level == CompLevel_all) {
160 if (TieredCompilation) {
161 // enough to be osr compilable at any level for tiered
162 result = !m->is_not_osr_compilable(CompLevel_simple) || !m->is_not_osr_compilable(CompLevel_full_optimization);
163 } else {
164 // must be osr compilable at available level for non-tiered
165 result = !m->is_not_osr_compilable(CompLevel_highest_tier);
166 }
167 } else if (is_compile(comp_level)) {
168 result = !m->is_not_osr_compilable(comp_level);
169 }
170 return (result && can_be_compiled(m, comp_level));
171 }
172
173 bool CompilationPolicy::is_compilation_enabled() {
174 // NOTE: CompileBroker::should_compile_new_jobs() checks for UseCompiler
175 return CompileBroker::should_compile_new_jobs();
176 }
177
178 CompileTask* CompilationPolicy::select_task_helper(CompileQueue* compile_queue) {
179 #if INCLUDE_JVMCI
180 if (UseJVMCICompiler && !BackgroundCompilation) {
181 /*
182 * In blocking compilation mode, the CompileBroker will make
183 * compilations submitted by a JVMCI compiler thread non-blocking. These
184 * compilations should be scheduled after all blocking compilations
185 * to service non-compiler related compilations sooner and reduce the
186 * chance of such compilations timing out.
187 */
188 for (CompileTask* task = compile_queue->first(); task != NULL; task = task->next()) {
189 if (task->is_blocking()) {
190 return task;
191 }
192 }
193 }
194 #endif
195 return compile_queue->first();
196 }
197
198 #ifndef PRODUCT
199 void NonTieredCompPolicy::trace_osr_completion(nmethod* osr_nm) {
200 if (TraceOnStackReplacement) {
201 if (osr_nm == NULL) tty->print_cr("compilation failed");
202 else tty->print_cr("nmethod " INTPTR_FORMAT, p2i(osr_nm));
203 }
204 }
205 #endif // !PRODUCT
206
207 void NonTieredCompPolicy::initialize() {
208 // Setup the compiler thread numbers
209 if (CICompilerCountPerCPU) {
210 // Example: if CICompilerCountPerCPU is true, then we get
211 // max(log2(8)-1,1) = 2 compiler threads on an 8-way machine.
212 // May help big-app startup time.
213 _compiler_count = MAX2(log2_int(os::active_processor_count())-1,1);
214 // Make sure there is enough space in the code cache to hold all the compiler buffers
215 size_t buffer_size = 1;
216 #ifdef COMPILER1
217 buffer_size = is_client_compilation_mode_vm() ? Compiler::code_buffer_size() : buffer_size;
218 #endif
219 #ifdef COMPILER2
220 buffer_size = is_server_compilation_mode_vm() ? C2Compiler::initial_code_buffer_size() : buffer_size;
221 #endif
222 int max_count = (ReservedCodeCacheSize - (CodeCacheMinimumUseSpace DEBUG_ONLY(* 3))) / (int)buffer_size;
223 if (_compiler_count > max_count) {
224 // Lower the compiler count such that all buffers fit into the code cache
225 _compiler_count = MAX2(max_count, 1);
226 }
227 FLAG_SET_ERGO(intx, CICompilerCount, _compiler_count);
228 } else {
229 _compiler_count = CICompilerCount;
230 }
231 }
232
233 // Note: this policy is used ONLY if TieredCompilation is off.
234 // compiler_count() behaves the following way:
235 // - with TIERED build (with both COMPILER1 and COMPILER2 defined) it should return
236 // zero for the c1 compilation levels in server compilation mode runs
237 // and c2 compilation levels in client compilation mode runs.
238 // - with COMPILER2 not defined it should return zero for c2 compilation levels.
239 // - with COMPILER1 not defined it should return zero for c1 compilation levels.
240 // - if neither is defined - always return zero.
241 int NonTieredCompPolicy::compiler_count(CompLevel comp_level) {
242 assert(!TieredCompilation, "This policy should not be used with TieredCompilation");
243 if (COMPILER2_PRESENT(is_server_compilation_mode_vm() && is_c2_compile(comp_level) ||)
244 is_client_compilation_mode_vm() && is_c1_compile(comp_level)) {
245 return _compiler_count;
246 }
247 return 0;
248 }
249
250 void NonTieredCompPolicy::reset_counter_for_invocation_event(const methodHandle& m) {
251 // Make sure invocation and backedge counter doesn't overflow again right away
252 // as would be the case for native methods.
253
254 // BUT also make sure the method doesn't look like it was never executed.
255 // Set carry bit and reduce counter's value to min(count, CompileThreshold/2).
256 MethodCounters* mcs = m->method_counters();
257 assert(mcs != NULL, "MethodCounters cannot be NULL for profiling");
258 mcs->invocation_counter()->set_carry();
259 mcs->backedge_counter()->set_carry();
260
261 assert(!m->was_never_executed(), "don't reset to 0 -- could be mistaken for never-executed");
262 }
263
264 void NonTieredCompPolicy::reset_counter_for_back_branch_event(const methodHandle& m) {
265 // Delay next back-branch event but pump up invocation counter to trigger
266 // whole method compilation.
267 MethodCounters* mcs = m->method_counters();
268 assert(mcs != NULL, "MethodCounters cannot be NULL for profiling");
269 InvocationCounter* i = mcs->invocation_counter();
270 InvocationCounter* b = mcs->backedge_counter();
271
272 // Don't set invocation_counter's value too low otherwise the method will
273 // look like immature (ic < ~5300) which prevents the inlining based on
274 // the type profiling.
275 i->set(i->state(), CompileThreshold);
276 // Don't reset counter too low - it is used to check if OSR method is ready.
277 b->set(b->state(), CompileThreshold / 2);
278 }
279
280 //
281 // CounterDecay
282 //
283 // Iterates through invocation counters and decrements them. This
284 // is done at each safepoint.
285 //
286 class CounterDecay : public AllStatic {
287 static jlong _last_timestamp;
288 static void do_method(Method* m) {
289 MethodCounters* mcs = m->method_counters();
290 if (mcs != NULL) {
291 mcs->invocation_counter()->decay();
292 }
293 }
294 public:
295 static void decay();
296 static bool is_decay_needed() {
297 return (os::javaTimeMillis() - _last_timestamp) > CounterDecayMinIntervalLength;
298 }
299 };
300
301 jlong CounterDecay::_last_timestamp = 0;
302
303 void CounterDecay::decay() {
304 _last_timestamp = os::javaTimeMillis();
305
306 // This operation is going to be performed only at the end of a safepoint
307 // and hence GC's will not be going on, all Java mutators are suspended
308 // at this point and hence SystemDictionary_lock is also not needed.
309 assert(SafepointSynchronize::is_at_safepoint(), "can only be executed at a safepoint");
310 size_t nclasses = ClassLoaderDataGraph::num_instance_classes();
311 size_t classes_per_tick = nclasses * (CounterDecayMinIntervalLength * 1e-3 /
312 CounterHalfLifeTime);
313 for (size_t i = 0; i < classes_per_tick; i++) {
314 InstanceKlass* k = ClassLoaderDataGraph::try_get_next_class();
315 if (k != NULL) {
316 k->methods_do(do_method);
317 }
318 }
319 }
320
321 // Called at the end of the safepoint
322 void NonTieredCompPolicy::do_safepoint_work() {
323 if(UseCounterDecay && CounterDecay::is_decay_needed()) {
324 CounterDecay::decay();
325 }
326 }
327
328 void NonTieredCompPolicy::reprofile(ScopeDesc* trap_scope, bool is_osr) {
329 ScopeDesc* sd = trap_scope;
330 MethodCounters* mcs;
331 InvocationCounter* c;
332 for (; !sd->is_top(); sd = sd->sender()) {
333 mcs = sd->method()->method_counters();
334 if (mcs != NULL) {
335 // Reset ICs of inlined methods, since they can trigger compilations also.
336 mcs->invocation_counter()->reset();
337 }
338 }
339 mcs = sd->method()->method_counters();
340 if (mcs != NULL) {
341 c = mcs->invocation_counter();
342 if (is_osr) {
343 // It was an OSR method, so bump the count higher.
344 c->set(c->state(), CompileThreshold);
345 } else {
346 c->reset();
347 }
348 mcs->backedge_counter()->reset();
349 }
350 }
351
352 // This method can be called by any component of the runtime to notify the policy
353 // that it's recommended to delay the compilation of this method.
354 void NonTieredCompPolicy::delay_compilation(Method* method) {
355 MethodCounters* mcs = method->method_counters();
356 if (mcs != NULL) {
357 mcs->invocation_counter()->decay();
358 mcs->backedge_counter()->decay();
359 }
360 }
361
362 void NonTieredCompPolicy::disable_compilation(Method* method) {
363 MethodCounters* mcs = method->method_counters();
364 if (mcs != NULL) {
365 mcs->invocation_counter()->set_state(InvocationCounter::wait_for_nothing);
366 mcs->backedge_counter()->set_state(InvocationCounter::wait_for_nothing);
367 }
368 }
369
370 CompileTask* NonTieredCompPolicy::select_task(CompileQueue* compile_queue) {
371 return select_task_helper(compile_queue);
372 }
373
374 bool NonTieredCompPolicy::is_mature(Method* method) {
375 MethodData* mdo = method->method_data();
376 assert(mdo != NULL, "Should be");
377 uint current = mdo->mileage_of(method);
378 uint initial = mdo->creation_mileage();
379 if (current < initial)
380 return true; // some sort of overflow
381 uint target;
382 if (ProfileMaturityPercentage <= 0)
383 target = (uint) -ProfileMaturityPercentage; // absolute value
384 else
385 target = (uint)( (ProfileMaturityPercentage * CompileThreshold) / 100 );
386 return (current >= initial + target);
387 }
388
389 nmethod* NonTieredCompPolicy::event(const methodHandle& method, const methodHandle& inlinee, int branch_bci,
390 int bci, CompLevel comp_level, CompiledMethod* nm, JavaThread* thread) {
391 assert(comp_level == CompLevel_none, "This should be only called from the interpreter");
392 NOT_PRODUCT(trace_frequency_counter_overflow(method, branch_bci, bci));
393 if (JvmtiExport::can_post_interpreter_events() && thread->is_interp_only_mode()) {
394 // If certain JVMTI events (e.g. frame pop event) are requested then the
395 // thread is forced to remain in interpreted code. This is
396 // implemented partly by a check in the run_compiled_code
397 // section of the interpreter whether we should skip running
398 // compiled code, and partly by skipping OSR compiles for
399 // interpreted-only threads.
400 if (bci != InvocationEntryBci) {
401 reset_counter_for_back_branch_event(method);
402 return NULL;
403 }
404 }
405 if (ReplayCompiles) {
406 // Don't trigger other compiles in testing mode
407 if (bci == InvocationEntryBci) {
408 reset_counter_for_invocation_event(method);
409 } else {
410 reset_counter_for_back_branch_event(method);
411 }
412 return NULL;
413 }
414
415 if (bci == InvocationEntryBci) {
416 // when code cache is full, compilation gets switched off, UseCompiler
417 // is set to false
418 if (!method->has_compiled_code() && UseCompiler) {
419 method_invocation_event(method, thread);
420 } else {
421 // Force counter overflow on method entry, even if no compilation
422 // happened. (The method_invocation_event call does this also.)
423 reset_counter_for_invocation_event(method);
424 }
425 // compilation at an invocation overflow no longer goes and retries test for
426 // compiled method. We always run the loser of the race as interpreted.
427 // so return NULL
428 return NULL;
429 } else {
430 // counter overflow in a loop => try to do on-stack-replacement
431 nmethod* osr_nm = method->lookup_osr_nmethod_for(bci, CompLevel_highest_tier, true);
432 NOT_PRODUCT(trace_osr_request(method, osr_nm, bci));
433 // when code cache is full, we should not compile any more...
434 if (osr_nm == NULL && UseCompiler) {
435 method_back_branch_event(method, bci, thread);
436 osr_nm = method->lookup_osr_nmethod_for(bci, CompLevel_highest_tier, true);
437 }
438 if (osr_nm == NULL) {
439 reset_counter_for_back_branch_event(method);
440 return NULL;
441 }
442 return osr_nm;
443 }
444 return NULL;
445 }
446
447 #ifndef PRODUCT
448 void NonTieredCompPolicy::trace_frequency_counter_overflow(const methodHandle& m, int branch_bci, int bci) {
449 if (TraceInvocationCounterOverflow) {
450 MethodCounters* mcs = m->method_counters();
451 assert(mcs != NULL, "MethodCounters cannot be NULL for profiling");
452 InvocationCounter* ic = mcs->invocation_counter();
453 InvocationCounter* bc = mcs->backedge_counter();
454 ResourceMark rm;
455 if (bci == InvocationEntryBci) {
456 tty->print("comp-policy cntr ovfl @ %d in entry of ", bci);
457 } else {
458 tty->print("comp-policy cntr ovfl @ %d in loop of ", bci);
459 }
460 m->print_value();
461 tty->cr();
462 ic->print();
463 bc->print();
464 if (ProfileInterpreter) {
465 if (bci != InvocationEntryBci) {
466 MethodData* mdo = m->method_data();
467 if (mdo != NULL) {
468 ProfileData *pd = mdo->bci_to_data(branch_bci);
469 if (pd == NULL) {
470 tty->print_cr("back branch count = N/A (missing ProfileData)");
471 } else {
472 tty->print_cr("back branch count = %d", pd->as_JumpData()->taken());
473 }
474 }
475 }
476 }
477 }
478 }
479
480 void NonTieredCompPolicy::trace_osr_request(const methodHandle& method, nmethod* osr, int bci) {
481 if (TraceOnStackReplacement) {
482 ResourceMark rm;
483 tty->print(osr != NULL ? "Reused OSR entry for " : "Requesting OSR entry for ");
484 method->print_short_name(tty);
485 tty->print_cr(" at bci %d", bci);
486 }
487 }
488 #endif // !PRODUCT
489
490 // SimpleCompPolicy - compile current method
491
492 void SimpleCompPolicy::method_invocation_event(const methodHandle& m, JavaThread* thread) {
493 const int comp_level = CompLevel_highest_tier;
494 const int hot_count = m->invocation_count();
495 reset_counter_for_invocation_event(m);
496
497 if (is_compilation_enabled() && can_be_compiled(m, comp_level)) {
498 CompiledMethod* nm = m->code();
499 if (nm == NULL ) {
500 CompileBroker::compile_method(m, InvocationEntryBci, comp_level, m, hot_count, CompileTask::Reason_InvocationCount, thread);
501 }
502 }
503 }
504
505 void SimpleCompPolicy::method_back_branch_event(const methodHandle& m, int bci, JavaThread* thread) {
506 const int comp_level = CompLevel_highest_tier;
507 const int hot_count = m->backedge_count();
508
509 if (is_compilation_enabled() && can_be_osr_compiled(m, comp_level)) {
510 CompileBroker::compile_method(m, bci, comp_level, m, hot_count, CompileTask::Reason_BackedgeCount, thread);
511 NOT_PRODUCT(trace_osr_completion(m->lookup_osr_nmethod_for(bci, comp_level, true));)
512 }
513 }
514 // StackWalkCompPolicy - walk up stack to find a suitable method to compile
515
516 #ifdef COMPILER2
517 const char* StackWalkCompPolicy::_msg = NULL;
518
519
520 // Consider m for compilation
521 void StackWalkCompPolicy::method_invocation_event(const methodHandle& m, JavaThread* thread) {
522 const int comp_level = CompLevel_highest_tier;
523 const int hot_count = m->invocation_count();
524 reset_counter_for_invocation_event(m);
525
526 if (is_compilation_enabled() && m->code() == NULL && can_be_compiled(m, comp_level)) {
527 ResourceMark rm(thread);
528 frame fr = thread->last_frame();
529 assert(fr.is_interpreted_frame(), "must be interpreted");
530 assert(fr.interpreter_frame_method() == m(), "bad method");
531
532 RegisterMap reg_map(thread, false);
533 javaVFrame* triggerVF = thread->last_java_vframe(®_map);
534 // triggerVF is the frame that triggered its counter
535 RFrame* first = new InterpretedRFrame(triggerVF->fr(), thread, m());
536
537 if (first->top_method()->code() != NULL) {
538 // called obsolete method/nmethod -- no need to recompile
539 } else {
540 GrowableArray<RFrame*>* stack = new GrowableArray<RFrame*>(50);
541 stack->push(first);
542 RFrame* top = findTopInlinableFrame(stack);
543 assert(top != NULL, "findTopInlinableFrame returned null");
544 CompileBroker::compile_method(top->top_method(), InvocationEntryBci, comp_level,
545 m, hot_count, CompileTask::Reason_InvocationCount, thread);
546 }
547 }
548 }
549
550 void StackWalkCompPolicy::method_back_branch_event(const methodHandle& m, int bci, JavaThread* thread) {
551 const int comp_level = CompLevel_highest_tier;
552 const int hot_count = m->backedge_count();
553
554 if (is_compilation_enabled() && can_be_osr_compiled(m, comp_level)) {
555 CompileBroker::compile_method(m, bci, comp_level, m, hot_count, CompileTask::Reason_BackedgeCount, thread);
556 NOT_PRODUCT(trace_osr_completion(m->lookup_osr_nmethod_for(bci, comp_level, true));)
557 }
558 }
559
560 RFrame* StackWalkCompPolicy::findTopInlinableFrame(GrowableArray<RFrame*>* stack) {
561 // go up the stack until finding a frame that (probably) won't be inlined
562 // into its caller
563 RFrame* current = stack->at(0); // current choice for stopping
564 assert( current && !current->is_compiled(), "" );
565 const char* msg = NULL;
566
567 while (1) {
568
569 // before going up the stack further, check if doing so would get us into
570 // compiled code
571 RFrame* next = senderOf(current, stack);
572 if( !next ) // No next frame up the stack?
573 break; // Then compile with current frame
574
575 Method* m = current->top_method();
576 Method* next_m = next->top_method();
577
578 if( !Inline ) { // Inlining turned off
579 msg = "Inlining turned off";
580 break;
581 }
582 if (next_m->is_not_compilable()) { // Did fail to compile this before/
583 msg = "caller not compilable";
584 break;
585 }
586 if (next->num() > MaxRecompilationSearchLength) {
587 // don't go up too high when searching for recompilees
588 msg = "don't go up any further: > MaxRecompilationSearchLength";
589 break;
590 }
591 if (next->distance() > MaxInterpretedSearchLength) {
592 // don't go up too high when searching for recompilees
593 msg = "don't go up any further: next > MaxInterpretedSearchLength";
594 break;
595 }
596 // Compiled frame above already decided not to inline;
597 // do not recompile him.
598 if (next->is_compiled()) {
599 msg = "not going up into optimized code";
600 break;
601 }
602
603 // Interpreted frame above us was already compiled. Do not force
604 // a recompile, although if the frame above us runs long enough an
605 // OSR might still happen.
606 if( current->is_interpreted() && next_m->has_compiled_code() ) {
607 msg = "not going up -- already compiled caller";
608 break;
609 }
610
611 // Compute how frequent this call site is. We have current method 'm'.
612 // We know next method 'next_m' is interpreted. Find the call site and
613 // check the various invocation counts.
614 int invcnt = 0; // Caller counts
615 if (ProfileInterpreter) {
616 invcnt = next_m->interpreter_invocation_count();
617 }
618 int cnt = 0; // Call site counts
619 if (ProfileInterpreter && next_m->method_data() != NULL) {
620 ResourceMark rm;
621 int bci = next->top_vframe()->bci();
622 ProfileData* data = next_m->method_data()->bci_to_data(bci);
623 if (data != NULL && data->is_CounterData())
624 cnt = data->as_CounterData()->count();
625 }
626
627 // Caller counts / call-site counts; i.e. is this call site
628 // a hot call site for method next_m?
629 int freq = (invcnt) ? cnt/invcnt : cnt;
630
631 // Check size and frequency limits
632 if ((msg = shouldInline(m, freq, cnt)) != NULL) {
633 break;
634 }
635 // Check inlining negative tests
636 if ((msg = shouldNotInline(m)) != NULL) {
637 break;
638 }
639
640
641 // If the caller method is too big or something then we do not want to
642 // compile it just to inline a method
643 if (!can_be_compiled(next_m, CompLevel_any)) {
644 msg = "caller cannot be compiled";
645 break;
646 }
647
648 if( next_m->name() == vmSymbols::class_initializer_name() ) {
649 msg = "do not compile class initializer (OSR ok)";
650 break;
651 }
652
653 current = next;
654 }
655
656 assert( !current || !current->is_compiled(), "" );
657
658 return current;
659 }
660
661 RFrame* StackWalkCompPolicy::senderOf(RFrame* rf, GrowableArray<RFrame*>* stack) {
662 RFrame* sender = rf->caller();
663 if (sender && sender->num() == stack->length()) stack->push(sender);
664 return sender;
665 }
666
667
668 const char* StackWalkCompPolicy::shouldInline(const methodHandle& m, float freq, int cnt) {
669 // Allows targeted inlining
670 // positive filter: should send be inlined? returns NULL (--> yes)
671 // or rejection msg
672 int max_size = MaxInlineSize;
673 int cost = m->code_size();
674
675 // Check for too many throws (and not too huge)
676 if (m->interpreter_throwout_count() > InlineThrowCount && cost < InlineThrowMaxSize ) {
677 return NULL;
678 }
679
680 // bump the max size if the call is frequent
681 if ((freq >= InlineFrequencyRatio) || (cnt >= InlineFrequencyCount)) {
682 if (TraceFrequencyInlining) {
683 tty->print("(Inlined frequent method)\n");
684 m->print();
685 }
686 max_size = FreqInlineSize;
687 }
688 if (cost > max_size) {
689 return (_msg = "too big");
690 }
691 return NULL;
692 }
693
694
695 const char* StackWalkCompPolicy::shouldNotInline(const methodHandle& m) {
696 // negative filter: should send NOT be inlined? returns NULL (--> inline) or rejection msg
697 if (m->is_abstract()) return (_msg = "abstract method");
698 // note: we allow ik->is_abstract()
699 if (!m->method_holder()->is_initialized()) return (_msg = "method holder not initialized");
700 if (m->is_native()) return (_msg = "native method");
701 CompiledMethod* m_code = m->code();
702 if (m_code != NULL && m_code->code_size() > InlineSmallCode)
703 return (_msg = "already compiled into a big method");
704
705 // use frequency-based objections only for non-trivial methods
706 if (m->code_size() <= MaxTrivialSize) return NULL;
707 if (UseInterpreter) { // don't use counts with -Xcomp
708 if ((m->code() == NULL) && m->was_never_executed()) return (_msg = "never executed");
709 if (!m->was_executed_more_than(MIN2(MinInliningThreshold, CompileThreshold >> 1))) return (_msg = "executed < MinInliningThreshold times");
710 }
711 if (Method::has_unloaded_classes_in_signature(m, JavaThread::current())) return (_msg = "unloaded signature classes");
712
713 return NULL;
714 }
715
716
717
718 #endif // COMPILER2