1 /*
2 * Copyright (c) 1998, 2014, 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 "ci/ciCallSite.hpp"
27 #include "ci/ciMethodHandle.hpp"
28 #include "classfile/vmSymbols.hpp"
29 #include "compiler/compileBroker.hpp"
30 #include "compiler/compileLog.hpp"
31 #include "interpreter/linkResolver.hpp"
32 #include "opto/addnode.hpp"
33 #include "opto/callGenerator.hpp"
34 #include "opto/castnode.hpp"
35 #include "opto/cfgnode.hpp"
36 #include "opto/mulnode.hpp"
37 #include "opto/parse.hpp"
38 #include "opto/rootnode.hpp"
39 #include "opto/runtime.hpp"
40 #include "opto/subnode.hpp"
41 #include "prims/nativeLookup.hpp"
42 #include "runtime/sharedRuntime.hpp"
43
44 void trace_type_profile(Compile* C, ciMethod *method, int depth, int bci, ciMethod *prof_method, ciKlass *prof_klass, int site_count, int receiver_count) {
45 if (TraceTypeProfile || C->print_inlining()) {
46 outputStream* out = tty;
47 if (!C->print_inlining()) {
48 if (!PrintOpto && !PrintCompilation) {
49 method->print_short_name();
50 tty->cr();
51 }
52 CompileTask::print_inlining_tty(prof_method, depth, bci);
53 } else {
54 out = C->print_inlining_stream();
55 }
56 CompileTask::print_inline_indent(depth, out);
57 out->print(" \\-> TypeProfile (%d/%d counts) = ", receiver_count, site_count);
58 stringStream ss;
59 prof_klass->name()->print_symbol_on(&ss);
60 out->print("%s", ss.as_string());
61 out->cr();
62 }
63 }
64
65 CallGenerator* Compile::call_generator(ciMethod* callee, int vtable_index, bool call_does_dispatch,
66 JVMState* jvms, bool allow_inline,
67 float prof_factor, ciKlass* speculative_receiver_type,
68 bool allow_intrinsics, bool delayed_forbidden) {
69 ciMethod* caller = jvms->method();
70 int bci = jvms->bci();
71 Bytecodes::Code bytecode = caller->java_code_at_bci(bci);
72 guarantee(callee != NULL, "failed method resolution");
73
74 // Dtrace currently doesn't work unless all calls are vanilla
75 if (env()->dtrace_method_probes()) {
76 allow_inline = false;
77 }
78
79 // Note: When we get profiling during stage-1 compiles, we want to pull
80 // from more specific profile data which pertains to this inlining.
81 // Right now, ignore the information in jvms->caller(), and do method[bci].
82 ciCallProfile profile = caller->call_profile_at_bci(bci);
83
84 // See how many times this site has been invoked.
85 int site_count = profile.count();
86 int receiver_count = -1;
87 if (call_does_dispatch && UseTypeProfile && profile.has_receiver(0)) {
88 // Receivers in the profile structure are ordered by call counts
89 // so that the most called (major) receiver is profile.receiver(0).
90 receiver_count = profile.receiver_count(0);
91 }
92
93 CompileLog* log = this->log();
94 if (log != NULL) {
95 int rid = (receiver_count >= 0)? log->identify(profile.receiver(0)): -1;
96 int r2id = (rid != -1 && profile.has_receiver(1))? log->identify(profile.receiver(1)):-1;
97 log->begin_elem("call method='%d' count='%d' prof_factor='%f'",
98 log->identify(callee), site_count, prof_factor);
99 if (call_does_dispatch) log->print(" virtual='1'");
100 if (allow_inline) log->print(" inline='1'");
101 if (receiver_count >= 0) {
102 log->print(" receiver='%d' receiver_count='%d'", rid, receiver_count);
103 if (profile.has_receiver(1)) {
104 log->print(" receiver2='%d' receiver2_count='%d'", r2id, profile.receiver_count(1));
105 }
106 }
107 if (callee->is_method_handle_intrinsic()) {
108 log->print(" method_handle_intrinsic='1'");
109 }
110 log->end_elem();
111 }
112
113 // Special case the handling of certain common, profitable library
114 // methods. If these methods are replaced with specialized code,
115 // then we return it as the inlined version of the call.
116 // We do this before the strict f.p. check below because the
117 // intrinsics handle strict f.p. correctly.
118 CallGenerator* cg_intrinsic = NULL;
119 if (allow_inline && allow_intrinsics) {
120 CallGenerator* cg = find_intrinsic(callee, call_does_dispatch);
121 if (cg != NULL) {
122 if (cg->is_predicated()) {
123 // Code without intrinsic but, hopefully, inlined.
124 CallGenerator* inline_cg = this->call_generator(callee,
125 vtable_index, call_does_dispatch, jvms, allow_inline, prof_factor, speculative_receiver_type, false);
126 if (inline_cg != NULL) {
127 cg = CallGenerator::for_predicated_intrinsic(cg, inline_cg);
128 }
129 }
130
131 // If intrinsic does the virtual dispatch, we try to use the type profile
132 // first, and hopefully inline it as the regular virtual call below.
133 // We will retry the intrinsic if nothing had claimed it afterwards.
134 if (cg->does_virtual_dispatch()) {
135 cg_intrinsic = cg;
136 cg = NULL;
137 } else {
138 return cg;
139 }
140 }
141 }
142
143 // Do method handle calls.
144 // NOTE: This must happen before normal inlining logic below since
145 // MethodHandle.invoke* are native methods which obviously don't
146 // have bytecodes and so normal inlining fails.
147 if (callee->is_method_handle_intrinsic()) {
148 CallGenerator* cg = CallGenerator::for_method_handle_call(jvms, caller, callee, delayed_forbidden);
149 assert(cg == NULL || !delayed_forbidden || !cg->is_late_inline() || cg->is_mh_late_inline(), "unexpected CallGenerator");
150 return cg;
151 }
152
153 // Do not inline strict fp into non-strict code, or the reverse
154 if (caller->is_strict() ^ callee->is_strict()) {
155 allow_inline = false;
156 }
157
158 // Attempt to inline...
159 if (allow_inline) {
160 // The profile data is only partly attributable to this caller,
161 // scale back the call site information.
162 float past_uses = jvms->method()->scale_count(site_count, prof_factor);
163 // This is the number of times we expect the call code to be used.
164 float expected_uses = past_uses;
165
166 // Try inlining a bytecoded method:
167 if (!call_does_dispatch) {
168 InlineTree* ilt = InlineTree::find_subtree_from_root(this->ilt(), jvms->caller(), jvms->method());
169 WarmCallInfo scratch_ci;
170 bool should_delay = false;
171 WarmCallInfo* ci = ilt->ok_to_inline(callee, jvms, profile, &scratch_ci, should_delay);
172 assert(ci != &scratch_ci, "do not let this pointer escape");
173 bool allow_inline = (ci != NULL && !ci->is_cold());
174 bool require_inline = (allow_inline && ci->is_hot());
175
176 if (allow_inline) {
177 CallGenerator* cg = CallGenerator::for_inline(callee, expected_uses);
178
179 if (require_inline && cg != NULL) {
180 // Delay the inlining of this method to give us the
181 // opportunity to perform some high level optimizations
182 // first.
183 if (should_delay_string_inlining(callee, jvms)) {
184 assert(!delayed_forbidden, "strange");
185 return CallGenerator::for_string_late_inline(callee, cg);
186 } else if (should_delay_boxing_inlining(callee, jvms)) {
187 assert(!delayed_forbidden, "strange");
188 return CallGenerator::for_boxing_late_inline(callee, cg);
189 } else if ((should_delay || AlwaysIncrementalInline) && !delayed_forbidden) {
190 return CallGenerator::for_late_inline(callee, cg);
191 }
192 }
193 if (cg == NULL || should_delay) {
194 // Fall through.
195 } else if (require_inline || !InlineWarmCalls) {
196 return cg;
197 } else {
198 CallGenerator* cold_cg = call_generator(callee, vtable_index, call_does_dispatch, jvms, false, prof_factor);
199 return CallGenerator::for_warm_call(ci, cold_cg, cg);
200 }
201 }
202 }
203
204 // Try using the type profile.
205 if (call_does_dispatch && site_count > 0 && receiver_count > 0) {
206 // The major receiver's count >= TypeProfileMajorReceiverPercent of site_count.
207 bool have_major_receiver = (100.*profile.receiver_prob(0) >= (float)TypeProfileMajorReceiverPercent);
208 ciMethod* receiver_method = NULL;
209
210 int morphism = profile.morphism();
211 if (speculative_receiver_type != NULL) {
212 if (!too_many_traps(caller, bci, Deoptimization::Reason_speculate_class_check)) {
213 // We have a speculative type, we should be able to resolve
214 // the call. We do that before looking at the profiling at
215 // this invoke because it may lead to bimorphic inlining which
216 // a speculative type should help us avoid.
217 receiver_method = callee->resolve_invoke(jvms->method()->holder(),
218 speculative_receiver_type);
219 if (receiver_method == NULL) {
220 speculative_receiver_type = NULL;
221 } else {
222 morphism = 1;
223 }
224 } else {
225 // speculation failed before. Use profiling at the call
226 // (could allow bimorphic inlining for instance).
227 speculative_receiver_type = NULL;
228 }
229 }
230 if (receiver_method == NULL &&
231 (have_major_receiver || morphism == 1 ||
232 (morphism == 2 && UseBimorphicInlining))) {
233 // receiver_method = profile.method();
234 // Profiles do not suggest methods now. Look it up in the major receiver.
235 receiver_method = callee->resolve_invoke(jvms->method()->holder(),
236 profile.receiver(0));
237 }
238 if (receiver_method != NULL) {
239 // The single majority receiver sufficiently outweighs the minority.
240 CallGenerator* hit_cg = this->call_generator(receiver_method,
241 vtable_index, !call_does_dispatch, jvms, allow_inline, prof_factor);
242 if (hit_cg != NULL) {
243 // Look up second receiver.
244 CallGenerator* next_hit_cg = NULL;
245 ciMethod* next_receiver_method = NULL;
246 if (morphism == 2 && UseBimorphicInlining) {
247 next_receiver_method = callee->resolve_invoke(jvms->method()->holder(),
248 profile.receiver(1));
249 if (next_receiver_method != NULL) {
250 next_hit_cg = this->call_generator(next_receiver_method,
251 vtable_index, !call_does_dispatch, jvms,
252 allow_inline, prof_factor);
253 if (next_hit_cg != NULL && !next_hit_cg->is_inline() &&
254 have_major_receiver && UseOnlyInlinedBimorphic) {
255 // Skip if we can't inline second receiver's method
256 next_hit_cg = NULL;
257 }
258 }
259 }
260 CallGenerator* miss_cg;
261 Deoptimization::DeoptReason reason = morphism == 2 ?
262 Deoptimization::Reason_bimorphic : Deoptimization::reason_class_check(speculative_receiver_type != NULL);
263 if ((morphism == 1 || (morphism == 2 && next_hit_cg != NULL)) &&
264 !too_many_traps(caller, bci, reason)
265 ) {
266 // Generate uncommon trap for class check failure path
267 // in case of monomorphic or bimorphic virtual call site.
268 miss_cg = CallGenerator::for_uncommon_trap(callee, reason,
269 Deoptimization::Action_maybe_recompile);
270 } else {
271 // Generate virtual call for class check failure path
272 // in case of polymorphic virtual call site.
273 miss_cg = CallGenerator::for_virtual_call(callee, vtable_index);
274 }
275 if (miss_cg != NULL) {
276 if (next_hit_cg != NULL) {
277 assert(speculative_receiver_type == NULL, "shouldn't end up here if we used speculation");
278 trace_type_profile(C, jvms->method(), jvms->depth() - 1, jvms->bci(), next_receiver_method, profile.receiver(1), site_count, profile.receiver_count(1));
279 // We don't need to record dependency on a receiver here and below.
280 // Whenever we inline, the dependency is added by Parse::Parse().
281 miss_cg = CallGenerator::for_predicted_call(profile.receiver(1), miss_cg, next_hit_cg, PROB_MAX);
282 }
283 if (miss_cg != NULL) {
284 trace_type_profile(C, jvms->method(), jvms->depth() - 1, jvms->bci(), receiver_method, profile.receiver(0), site_count, receiver_count);
285 ciKlass* k = speculative_receiver_type != NULL ? speculative_receiver_type : profile.receiver(0);
286 float hit_prob = speculative_receiver_type != NULL ? 1.0 : profile.receiver_prob(0);
287 CallGenerator* cg = CallGenerator::for_predicted_call(k, miss_cg, hit_cg, hit_prob);
288 if (cg != NULL) return cg;
289 }
290 }
291 }
292 }
293 }
294 }
295
296 // Nothing claimed the intrinsic, we go with straight-forward inlining
297 // for already discovered intrinsic.
298 if (allow_inline && allow_intrinsics && cg_intrinsic != NULL) {
299 assert(cg_intrinsic->does_virtual_dispatch(), "sanity");
300 return cg_intrinsic;
301 }
302
303 // There was no special inlining tactic, or it bailed out.
304 // Use a more generic tactic, like a simple call.
305 if (call_does_dispatch) {
306 const char* msg = "virtual call";
307 if (PrintInlining) print_inlining(callee, jvms->depth() - 1, jvms->bci(), msg);
308 C->log_inline_failure(msg);
309 return CallGenerator::for_virtual_call(callee, vtable_index);
310 } else {
311 // Class Hierarchy Analysis or Type Profile reveals a unique target,
312 // or it is a static or special call.
313 return CallGenerator::for_direct_call(callee, should_delay_inlining(callee, jvms));
314 }
315 }
316
317 // Return true for methods that shouldn't be inlined early so that
318 // they are easier to analyze and optimize as intrinsics.
319 bool Compile::should_delay_string_inlining(ciMethod* call_method, JVMState* jvms) {
320 if (has_stringbuilder()) {
321
322 if ((call_method->holder() == C->env()->StringBuilder_klass() ||
323 call_method->holder() == C->env()->StringBuffer_klass()) &&
324 (jvms->method()->holder() == C->env()->StringBuilder_klass() ||
325 jvms->method()->holder() == C->env()->StringBuffer_klass())) {
326 // Delay SB calls only when called from non-SB code
327 return false;
328 }
329
330 switch (call_method->intrinsic_id()) {
331 case vmIntrinsics::_StringBuilder_void:
332 case vmIntrinsics::_StringBuilder_int:
333 case vmIntrinsics::_StringBuilder_String:
334 case vmIntrinsics::_StringBuilder_append_char:
335 case vmIntrinsics::_StringBuilder_append_int:
336 case vmIntrinsics::_StringBuilder_append_String:
337 case vmIntrinsics::_StringBuilder_toString:
338 case vmIntrinsics::_StringBuffer_void:
339 case vmIntrinsics::_StringBuffer_int:
340 case vmIntrinsics::_StringBuffer_String:
341 case vmIntrinsics::_StringBuffer_append_char:
342 case vmIntrinsics::_StringBuffer_append_int:
343 case vmIntrinsics::_StringBuffer_append_String:
344 case vmIntrinsics::_StringBuffer_toString:
345 case vmIntrinsics::_Integer_toString:
346 return true;
347
348 case vmIntrinsics::_String_String:
349 {
350 Node* receiver = jvms->map()->in(jvms->argoff() + 1);
351 if (receiver->is_Proj() && receiver->in(0)->is_CallStaticJava()) {
352 CallStaticJavaNode* csj = receiver->in(0)->as_CallStaticJava();
353 ciMethod* m = csj->method();
354 if (m != NULL &&
355 (m->intrinsic_id() == vmIntrinsics::_StringBuffer_toString ||
356 m->intrinsic_id() == vmIntrinsics::_StringBuilder_toString))
357 // Delay String.<init>(new SB())
358 return true;
359 }
360 return false;
361 }
362
363 default:
364 return false;
365 }
366 }
367 return false;
368 }
369
370 bool Compile::should_delay_boxing_inlining(ciMethod* call_method, JVMState* jvms) {
371 if (eliminate_boxing() && call_method->is_boxing_method()) {
372 set_has_boxed_value(true);
373 return aggressive_unboxing();
374 }
375 return false;
376 }
377
378 // uncommon-trap call-sites where callee is unloaded, uninitialized or will not link
379 bool Parse::can_not_compile_call_site(ciMethod *dest_method, ciInstanceKlass* klass) {
380 // Additional inputs to consider...
381 // bc = bc()
382 // caller = method()
383 // iter().get_method_holder_index()
384 assert( dest_method->is_loaded(), "ciTypeFlow should not let us get here" );
385 // Interface classes can be loaded & linked and never get around to
386 // being initialized. Uncommon-trap for not-initialized static or
387 // v-calls. Let interface calls happen.
388 ciInstanceKlass* holder_klass = dest_method->holder();
389 if (!holder_klass->is_being_initialized() &&
390 !holder_klass->is_initialized() &&
391 !holder_klass->is_interface()) {
392 uncommon_trap(Deoptimization::Reason_uninitialized,
393 Deoptimization::Action_reinterpret,
394 holder_klass);
395 return true;
396 }
397
398 assert(dest_method->is_loaded(), "dest_method: typeflow responsibility");
399 return false;
400 }
401
402 #ifdef ASSERT
403 static bool check_call_consistency(JVMState* jvms, CallGenerator* cg) {
404 ciMethod* symbolic_info = jvms->method()->get_method_at_bci(jvms->bci());
405 ciMethod* resolved_method = cg->method();
406 if (!ciMethod::is_consistent_info(symbolic_info, resolved_method)) {
407 tty->print_cr("JVMS:");
408 jvms->dump();
409 tty->print_cr("Bytecode info:");
410 jvms->method()->get_method_at_bci(jvms->bci())->print(); tty->cr();
411 tty->print_cr("Resolved method:");
412 cg->method()->print(); tty->cr();
413 return false;
414 }
415 return true;
416 }
417 #endif // ASSERT
418
419 //------------------------------do_call----------------------------------------
420 // Handle your basic call. Inline if we can & want to, else just setup call.
421 void Parse::do_call() {
422 // It's likely we are going to add debug info soon.
423 // Also, if we inline a guy who eventually needs debug info for this JVMS,
424 // our contribution to it is cleaned up right here.
425 kill_dead_locals();
426
427 C->print_inlining_assert_ready();
428
429 // Set frequently used booleans
430 const bool is_virtual = bc() == Bytecodes::_invokevirtual;
431 const bool is_virtual_or_interface = is_virtual || bc() == Bytecodes::_invokeinterface;
432 const bool has_receiver = Bytecodes::has_receiver(bc());
433
434 // Find target being called
435 bool will_link;
436 ciSignature* declared_signature = NULL;
437 ciMethod* orig_callee = iter().get_method(will_link, &declared_signature); // callee in the bytecode
438 ciInstanceKlass* holder_klass = orig_callee->holder();
439 ciKlass* holder = iter().get_declared_method_holder();
440 ciInstanceKlass* klass = ciEnv::get_instance_klass_for_declared_method_holder(holder);
441 assert(declared_signature != NULL, "cannot be null");
442
443 // Bump max node limit for JSR292 users
444 if (bc() == Bytecodes::_invokedynamic || orig_callee->is_method_handle_intrinsic()) {
445 C->set_max_node_limit(3*MaxNodeLimit);
446 }
447
448 // uncommon-trap when callee is unloaded, uninitialized or will not link
449 // bailout when too many arguments for register representation
450 if (!will_link || can_not_compile_call_site(orig_callee, klass)) {
451 if (PrintOpto && (Verbose || WizardMode)) {
452 method()->print_name(); tty->print_cr(" can not compile call at bci %d to:", bci());
453 orig_callee->print_name(); tty->cr();
454 }
455 return;
456 }
457 assert(holder_klass->is_loaded(), "");
458 //assert((bc_callee->is_static() || is_invokedynamic) == !has_receiver , "must match bc"); // XXX invokehandle (cur_bc_raw)
459 // Note: this takes into account invokeinterface of methods declared in java/lang/Object,
460 // which should be invokevirtuals but according to the VM spec may be invokeinterfaces
461 assert(holder_klass->is_interface() || holder_klass->super() == NULL || (bc() != Bytecodes::_invokeinterface), "must match bc");
462 // Note: In the absence of miranda methods, an abstract class K can perform
463 // an invokevirtual directly on an interface method I.m if K implements I.
464
465 // orig_callee is the resolved callee which's signature includes the
466 // appendix argument.
467 const int nargs = orig_callee->arg_size();
468 const bool is_signature_polymorphic = MethodHandles::is_signature_polymorphic(orig_callee->intrinsic_id());
469
470 // Push appendix argument (MethodType, CallSite, etc.), if one.
471 if (iter().has_appendix()) {
472 ciObject* appendix_arg = iter().get_appendix();
473 const TypeOopPtr* appendix_arg_type = TypeOopPtr::make_from_constant(appendix_arg);
474 Node* appendix_arg_node = _gvn.makecon(appendix_arg_type);
475 push(appendix_arg_node);
476 }
477
478 // ---------------------
479 // Does Class Hierarchy Analysis reveal only a single target of a v-call?
480 // Then we may inline or make a static call, but become dependent on there being only 1 target.
481 // Does the call-site type profile reveal only one receiver?
482 // Then we may introduce a run-time check and inline on the path where it succeeds.
483 // The other path may uncommon_trap, check for another receiver, or do a v-call.
484
485 // Try to get the most accurate receiver type
486 ciMethod* callee = orig_callee;
487 int vtable_index = Method::invalid_vtable_index;
488 bool call_does_dispatch = false;
489
490 // Speculative type of the receiver if any
491 ciKlass* speculative_receiver_type = NULL;
492 if (is_virtual_or_interface) {
493 Node* receiver_node = stack(sp() - nargs);
494 const TypeOopPtr* receiver_type = _gvn.type(receiver_node)->isa_oopptr();
495 // call_does_dispatch and vtable_index are out-parameters. They might be changed.
496 // For arrays, klass below is Object. When vtable calls are used,
497 // resolving the call with Object would allow an illegal call to
498 // finalize() on an array. We use holder instead: illegal calls to
499 // finalize() won't be compiled as vtable calls (IC call
500 // resolution will catch the illegal call) and the few legal calls
501 // on array types won't be either.
502 callee = C->optimize_virtual_call(method(), bci(), klass, holder, orig_callee,
503 receiver_type, is_virtual,
504 call_does_dispatch, vtable_index); // out-parameters
505 speculative_receiver_type = receiver_type != NULL ? receiver_type->speculative_type() : NULL;
506 }
507
508 // Note: It's OK to try to inline a virtual call.
509 // The call generator will not attempt to inline a polymorphic call
510 // unless it knows how to optimize the receiver dispatch.
511 bool try_inline = (C->do_inlining() || InlineAccessors);
512
513 // ---------------------
514 dec_sp(nargs); // Temporarily pop args for JVM state of call
515 JVMState* jvms = sync_jvms();
516
517 // ---------------------
518 // Decide call tactic.
519 // This call checks with CHA, the interpreter profile, intrinsics table, etc.
520 // It decides whether inlining is desirable or not.
521 CallGenerator* cg = C->call_generator(callee, vtable_index, call_does_dispatch, jvms, try_inline, prof_factor(), speculative_receiver_type);
522
523 // NOTE: Don't use orig_callee and callee after this point! Use cg->method() instead.
524 orig_callee = callee = NULL;
525
526 // ---------------------
527 // Round double arguments before call
528 round_double_arguments(cg->method());
529
530 // Feed profiling data for arguments to the type system so it can
531 // propagate it as speculative types
532 record_profiled_arguments_for_speculation(cg->method(), bc());
533
534 #ifndef PRODUCT
535 // bump global counters for calls
536 count_compiled_calls(/*at_method_entry*/ false, cg->is_inline());
537
538 // Record first part of parsing work for this call
539 parse_histogram()->record_change();
540 #endif // not PRODUCT
541
542 assert(jvms == this->jvms(), "still operating on the right JVMS");
543 assert(jvms_in_sync(), "jvms must carry full info into CG");
544
545 // save across call, for a subsequent cast_not_null.
546 Node* receiver = has_receiver ? argument(0) : NULL;
547
548 // The extra CheckCastPP for speculative types mess with PhaseStringOpts
549 if (receiver != NULL && !call_does_dispatch && !cg->is_string_late_inline()) {
550 // Feed profiling data for a single receiver to the type system so
551 // it can propagate it as a speculative type
552 receiver = record_profiled_receiver_for_speculation(receiver);
553 }
554
555 // Bump method data counters (We profile *before* the call is made
556 // because exceptions don't return to the call site.)
557 profile_call(receiver);
558
559 JVMState* new_jvms = cg->generate(jvms);
560 if (new_jvms == NULL) {
561 // When inlining attempt fails (e.g., too many arguments),
562 // it may contaminate the current compile state, making it
563 // impossible to pull back and try again. Once we call
564 // cg->generate(), we are committed. If it fails, the whole
565 // compilation task is compromised.
566 if (failing()) return;
567
568 // This can happen if a library intrinsic is available, but refuses
569 // the call site, perhaps because it did not match a pattern the
570 // intrinsic was expecting to optimize. Should always be possible to
571 // get a normal java call that may inline in that case
572 cg = C->call_generator(cg->method(), vtable_index, call_does_dispatch, jvms, try_inline, prof_factor(), speculative_receiver_type, /* allow_intrinsics= */ false);
573 new_jvms = cg->generate(jvms);
574 if (new_jvms == NULL) {
575 guarantee(failing(), "call failed to generate: calls should work");
576 return;
577 }
578 }
579
580 if (cg->is_inline()) {
581 // Accumulate has_loops estimate
582 C->set_has_loops(C->has_loops() || cg->method()->has_loops());
583 C->env()->notice_inlined_method(cg->method());
584 }
585
586 // Reset parser state from [new_]jvms, which now carries results of the call.
587 // Return value (if any) is already pushed on the stack by the cg.
588 add_exception_states_from(new_jvms);
589 if (new_jvms->map()->control() == top()) {
590 stop_and_kill_map();
591 } else {
592 assert(new_jvms->same_calls_as(jvms), "method/bci left unchanged");
593 set_jvms(new_jvms);
594 }
595
596 assert(check_call_consistency(jvms, cg), "inconsistent info");
597
598 if (!stopped()) {
599 // This was some sort of virtual call, which did a null check for us.
600 // Now we can assert receiver-not-null, on the normal return path.
601 if (receiver != NULL && cg->is_virtual()) {
602 Node* cast = cast_not_null(receiver);
603 // %%% assert(receiver == cast, "should already have cast the receiver");
604 }
605
606 // Round double result after a call from strict to non-strict code
607 round_double_result(cg->method());
608
609 ciType* rtype = cg->method()->return_type();
610 ciType* ctype = declared_signature->return_type();
611
612 if (Bytecodes::has_optional_appendix(iter().cur_bc_raw()) || is_signature_polymorphic) {
613 // Be careful here with return types.
614 if (ctype != rtype) {
615 BasicType rt = rtype->basic_type();
616 BasicType ct = ctype->basic_type();
617 if (ct == T_VOID) {
618 // It's OK for a method to return a value that is discarded.
619 // The discarding does not require any special action from the caller.
620 // The Java code knows this, at VerifyType.isNullConversion.
621 pop_node(rt); // whatever it was, pop it
622 } else if (rt == T_INT || is_subword_type(rt)) {
623 // Nothing. These cases are handled in lambda form bytecode.
624 assert(ct == T_INT || is_subword_type(ct), "must match: rt=%s, ct=%s", type2name(rt), type2name(ct));
625 } else if (rt == T_OBJECT || rt == T_ARRAY) {
626 assert(ct == T_OBJECT || ct == T_ARRAY, "rt=%s, ct=%s", type2name(rt), type2name(ct));
627 if (ctype->is_loaded()) {
628 const TypeOopPtr* arg_type = TypeOopPtr::make_from_klass(rtype->as_klass());
629 const Type* sig_type = TypeOopPtr::make_from_klass(ctype->as_klass());
630 if (arg_type != NULL && !arg_type->higher_equal(sig_type)) {
631 Node* retnode = pop();
632 Node* cast_obj = _gvn.transform(new CheckCastPPNode(control(), retnode, sig_type));
633 push(cast_obj);
634 }
635 }
636 } else {
637 assert(rt == ct, "unexpected mismatch: rt=%s, ct=%s", type2name(rt), type2name(ct));
638 // push a zero; it's better than getting an oop/int mismatch
639 pop_node(rt);
640 Node* retnode = zerocon(ct);
641 push_node(ct, retnode);
642 }
643 // Now that the value is well-behaved, continue with the call-site type.
644 rtype = ctype;
645 }
646 } else {
647 // Symbolic resolution enforces the types to be the same.
648 // NOTE: We must relax the assert for unloaded types because two
649 // different ciType instances of the same unloaded class type
650 // can appear to be "loaded" by different loaders (depending on
651 // the accessing class).
652 assert(!rtype->is_loaded() || !ctype->is_loaded() || rtype == ctype,
653 "mismatched return types: rtype=%s, ctype=%s", rtype->name(), ctype->name());
654 }
655
656 // If the return type of the method is not loaded, assert that the
657 // value we got is a null. Otherwise, we need to recompile.
658 if (!rtype->is_loaded()) {
659 if (PrintOpto && (Verbose || WizardMode)) {
660 method()->print_name(); tty->print_cr(" asserting nullness of result at bci: %d", bci());
661 cg->method()->print_name(); tty->cr();
662 }
663 if (C->log() != NULL) {
664 C->log()->elem("assert_null reason='return' klass='%d'",
665 C->log()->identify(rtype));
666 }
667 // If there is going to be a trap, put it at the next bytecode:
668 set_bci(iter().next_bci());
669 null_assert(peek());
670 set_bci(iter().cur_bci()); // put it back
671 }
672 BasicType ct = ctype->basic_type();
673 if (ct == T_OBJECT || ct == T_ARRAY) {
674 record_profiled_return_for_speculation();
675 }
676 }
677
678 // Restart record of parsing work after possible inlining of call
679 #ifndef PRODUCT
680 parse_histogram()->set_initial_state(bc());
681 #endif
682 }
683
684 //---------------------------catch_call_exceptions-----------------------------
685 // Put a Catch and CatchProj nodes behind a just-created call.
686 // Send their caught exceptions to the proper handler.
687 // This may be used after a call to the rethrow VM stub,
688 // when it is needed to process unloaded exception classes.
689 void Parse::catch_call_exceptions(ciExceptionHandlerStream& handlers) {
690 // Exceptions are delivered through this channel:
691 Node* i_o = this->i_o();
692
693 // Add a CatchNode.
694 GrowableArray<int>* bcis = new (C->node_arena()) GrowableArray<int>(C->node_arena(), 8, 0, -1);
695 GrowableArray<const Type*>* extypes = new (C->node_arena()) GrowableArray<const Type*>(C->node_arena(), 8, 0, NULL);
696 GrowableArray<int>* saw_unloaded = new (C->node_arena()) GrowableArray<int>(C->node_arena(), 8, 0, 0);
697
698 for (; !handlers.is_done(); handlers.next()) {
699 ciExceptionHandler* h = handlers.handler();
700 int h_bci = h->handler_bci();
701 ciInstanceKlass* h_klass = h->is_catch_all() ? env()->Throwable_klass() : h->catch_klass();
702 // Do not introduce unloaded exception types into the graph:
703 if (!h_klass->is_loaded()) {
704 if (saw_unloaded->contains(h_bci)) {
705 /* We've already seen an unloaded exception with h_bci,
706 so don't duplicate. Duplication will cause the CatchNode to be
707 unnecessarily large. See 4713716. */
708 continue;
709 } else {
710 saw_unloaded->append(h_bci);
711 }
712 }
713 const Type* h_extype = TypeOopPtr::make_from_klass(h_klass);
714 // (We use make_from_klass because it respects UseUniqueSubclasses.)
715 h_extype = h_extype->join(TypeInstPtr::NOTNULL);
716 assert(!h_extype->empty(), "sanity");
717 // Note: It's OK if the BCIs repeat themselves.
718 bcis->append(h_bci);
719 extypes->append(h_extype);
720 }
721
722 int len = bcis->length();
723 CatchNode *cn = new CatchNode(control(), i_o, len+1);
724 Node *catch_ = _gvn.transform(cn);
725
726 // now branch with the exception state to each of the (potential)
727 // handlers
728 for(int i=0; i < len; i++) {
729 // Setup JVM state to enter the handler.
730 PreserveJVMState pjvms(this);
731 // Locals are just copied from before the call.
732 // Get control from the CatchNode.
733 int handler_bci = bcis->at(i);
734 Node* ctrl = _gvn.transform( new CatchProjNode(catch_, i+1,handler_bci));
735 // This handler cannot happen?
736 if (ctrl == top()) continue;
737 set_control(ctrl);
738
739 // Create exception oop
740 const TypeInstPtr* extype = extypes->at(i)->is_instptr();
741 Node *ex_oop = _gvn.transform(new CreateExNode(extypes->at(i), ctrl, i_o));
742
743 // Handle unloaded exception classes.
744 if (saw_unloaded->contains(handler_bci)) {
745 // An unloaded exception type is coming here. Do an uncommon trap.
746 #ifndef PRODUCT
747 // We do not expect the same handler bci to take both cold unloaded
748 // and hot loaded exceptions. But, watch for it.
749 if ((Verbose || WizardMode) && extype->is_loaded()) {
750 tty->print("Warning: Handler @%d takes mixed loaded/unloaded exceptions in ", bci());
751 method()->print_name(); tty->cr();
752 } else if (PrintOpto && (Verbose || WizardMode)) {
753 tty->print("Bailing out on unloaded exception type ");
754 extype->klass()->print_name();
755 tty->print(" at bci:%d in ", bci());
756 method()->print_name(); tty->cr();
757 }
758 #endif
759 // Emit an uncommon trap instead of processing the block.
760 set_bci(handler_bci);
761 push_ex_oop(ex_oop);
762 uncommon_trap(Deoptimization::Reason_unloaded,
763 Deoptimization::Action_reinterpret,
764 extype->klass(), "!loaded exception");
765 set_bci(iter().cur_bci()); // put it back
766 continue;
767 }
768
769 // go to the exception handler
770 if (handler_bci < 0) { // merge with corresponding rethrow node
771 throw_to_exit(make_exception_state(ex_oop));
772 } else { // Else jump to corresponding handle
773 push_ex_oop(ex_oop); // Clear stack and push just the oop.
774 merge_exception(handler_bci);
775 }
776 }
777
778 // The first CatchProj is for the normal return.
779 // (Note: If this is a call to rethrow_Java, this node goes dead.)
780 set_control(_gvn.transform( new CatchProjNode(catch_, CatchProjNode::fall_through_index, CatchProjNode::no_handler_bci)));
781 }
782
783
784 //----------------------------catch_inline_exceptions--------------------------
785 // Handle all exceptions thrown by an inlined method or individual bytecode.
786 // Common case 1: we have no handler, so all exceptions merge right into
787 // the rethrow case.
788 // Case 2: we have some handlers, with loaded exception klasses that have
789 // no subklasses. We do a Deutsch-Shiffman style type-check on the incoming
790 // exception oop and branch to the handler directly.
791 // Case 3: We have some handlers with subklasses or are not loaded at
792 // compile-time. We have to call the runtime to resolve the exception.
793 // So we insert a RethrowCall and all the logic that goes with it.
794 void Parse::catch_inline_exceptions(SafePointNode* ex_map) {
795 // Caller is responsible for saving away the map for normal control flow!
796 assert(stopped(), "call set_map(NULL) first");
797 assert(method()->has_exception_handlers(), "don't come here w/o work to do");
798
799 Node* ex_node = saved_ex_oop(ex_map);
800 if (ex_node == top()) {
801 // No action needed.
802 return;
803 }
804 const TypeInstPtr* ex_type = _gvn.type(ex_node)->isa_instptr();
805 NOT_PRODUCT(if (ex_type==NULL) tty->print_cr("*** Exception not InstPtr"));
806 if (ex_type == NULL)
807 ex_type = TypeOopPtr::make_from_klass(env()->Throwable_klass())->is_instptr();
808
809 // determine potential exception handlers
810 ciExceptionHandlerStream handlers(method(), bci(),
811 ex_type->klass()->as_instance_klass(),
812 ex_type->klass_is_exact());
813
814 // Start executing from the given throw state. (Keep its stack, for now.)
815 // Get the exception oop as known at compile time.
816 ex_node = use_exception_state(ex_map);
817
818 // Get the exception oop klass from its header
819 Node* ex_klass_node = NULL;
820 if (has_ex_handler() && !ex_type->klass_is_exact()) {
821 Node* p = basic_plus_adr( ex_node, ex_node, oopDesc::klass_offset_in_bytes());
822 ex_klass_node = _gvn.transform(LoadKlassNode::make(_gvn, NULL, immutable_memory(), p, TypeInstPtr::KLASS, TypeKlassPtr::OBJECT));
823
824 // Compute the exception klass a little more cleverly.
825 // Obvious solution is to simple do a LoadKlass from the 'ex_node'.
826 // However, if the ex_node is a PhiNode, I'm going to do a LoadKlass for
827 // each arm of the Phi. If I know something clever about the exceptions
828 // I'm loading the class from, I can replace the LoadKlass with the
829 // klass constant for the exception oop.
830 if (ex_node->is_Phi()) {
831 ex_klass_node = new PhiNode(ex_node->in(0), TypeKlassPtr::OBJECT);
832 for (uint i = 1; i < ex_node->req(); i++) {
833 Node* ex_in = ex_node->in(i);
834 if (ex_in == top() || ex_in == NULL) {
835 // This path was not taken.
836 ex_klass_node->init_req(i, top());
837 continue;
838 }
839 Node* p = basic_plus_adr(ex_in, ex_in, oopDesc::klass_offset_in_bytes());
840 Node* k = _gvn.transform( LoadKlassNode::make(_gvn, NULL, immutable_memory(), p, TypeInstPtr::KLASS, TypeKlassPtr::OBJECT));
841 ex_klass_node->init_req( i, k );
842 }
843 _gvn.set_type(ex_klass_node, TypeKlassPtr::OBJECT);
844
845 }
846 }
847
848 // Scan the exception table for applicable handlers.
849 // If none, we can call rethrow() and be done!
850 // If precise (loaded with no subklasses), insert a D.S. style
851 // pointer compare to the correct handler and loop back.
852 // If imprecise, switch to the Rethrow VM-call style handling.
853
854 int remaining = handlers.count_remaining();
855
856 // iterate through all entries sequentially
857 for (;!handlers.is_done(); handlers.next()) {
858 ciExceptionHandler* handler = handlers.handler();
859
860 if (handler->is_rethrow()) {
861 // If we fell off the end of the table without finding an imprecise
862 // exception klass (and without finding a generic handler) then we
863 // know this exception is not handled in this method. We just rethrow
864 // the exception into the caller.
865 throw_to_exit(make_exception_state(ex_node));
866 return;
867 }
868
869 // exception handler bci range covers throw_bci => investigate further
870 int handler_bci = handler->handler_bci();
871
872 if (remaining == 1) {
873 push_ex_oop(ex_node); // Push exception oop for handler
874 if (PrintOpto && WizardMode) {
875 tty->print_cr(" Catching every inline exception bci:%d -> handler_bci:%d", bci(), handler_bci);
876 }
877 merge_exception(handler_bci); // jump to handler
878 return; // No more handling to be done here!
879 }
880
881 // Get the handler's klass
882 ciInstanceKlass* klass = handler->catch_klass();
883
884 if (!klass->is_loaded()) { // klass is not loaded?
885 // fall through into catch_call_exceptions which will emit a
886 // handler with an uncommon trap.
887 break;
888 }
889
890 if (klass->is_interface()) // should not happen, but...
891 break; // bail out
892
893 // Check the type of the exception against the catch type
894 const TypeKlassPtr *tk = TypeKlassPtr::make(klass);
895 Node* con = _gvn.makecon(tk);
896 Node* not_subtype_ctrl = gen_subtype_check(ex_klass_node, con);
897 if (!stopped()) {
898 PreserveJVMState pjvms(this);
899 const TypeInstPtr* tinst = TypeOopPtr::make_from_klass_unique(klass)->cast_to_ptr_type(TypePtr::NotNull)->is_instptr();
900 assert(klass->has_subklass() || tinst->klass_is_exact(), "lost exactness");
901 Node* ex_oop = _gvn.transform(new CheckCastPPNode(control(), ex_node, tinst));
902 push_ex_oop(ex_oop); // Push exception oop for handler
903 if (PrintOpto && WizardMode) {
904 tty->print(" Catching inline exception bci:%d -> handler_bci:%d -- ", bci(), handler_bci);
905 klass->print_name();
906 tty->cr();
907 }
908 merge_exception(handler_bci);
909 }
910 set_control(not_subtype_ctrl);
911
912 // Come here if exception does not match handler.
913 // Carry on with more handler checks.
914 --remaining;
915 }
916
917 assert(!stopped(), "you should return if you finish the chain");
918
919 // Oops, need to call into the VM to resolve the klasses at runtime.
920 // Note: This call must not deoptimize, since it is not a real at this bci!
921 kill_dead_locals();
922
923 make_runtime_call(RC_NO_LEAF | RC_MUST_THROW,
924 OptoRuntime::rethrow_Type(),
925 OptoRuntime::rethrow_stub(),
926 NULL, NULL,
927 ex_node);
928
929 // Rethrow is a pure call, no side effects, only a result.
930 // The result cannot be allocated, so we use I_O
931
932 // Catch exceptions from the rethrow
933 catch_call_exceptions(handlers);
934 }
935
936
937 // (Note: Moved add_debug_info into GraphKit::add_safepoint_edges.)
938
939
940 #ifndef PRODUCT
941 void Parse::count_compiled_calls(bool at_method_entry, bool is_inline) {
942 if( CountCompiledCalls ) {
943 if( at_method_entry ) {
944 // bump invocation counter if top method (for statistics)
945 if (CountCompiledCalls && depth() == 1) {
946 const TypePtr* addr_type = TypeMetadataPtr::make(method());
947 Node* adr1 = makecon(addr_type);
948 Node* adr2 = basic_plus_adr(adr1, adr1, in_bytes(Method::compiled_invocation_counter_offset()));
949 increment_counter(adr2);
950 }
951 } else if (is_inline) {
952 switch (bc()) {
953 case Bytecodes::_invokevirtual: increment_counter(SharedRuntime::nof_inlined_calls_addr()); break;
954 case Bytecodes::_invokeinterface: increment_counter(SharedRuntime::nof_inlined_interface_calls_addr()); break;
955 case Bytecodes::_invokestatic:
956 case Bytecodes::_invokedynamic:
957 case Bytecodes::_invokespecial: increment_counter(SharedRuntime::nof_inlined_static_calls_addr()); break;
958 default: fatal("unexpected call bytecode");
959 }
960 } else {
961 switch (bc()) {
962 case Bytecodes::_invokevirtual: increment_counter(SharedRuntime::nof_normal_calls_addr()); break;
963 case Bytecodes::_invokeinterface: increment_counter(SharedRuntime::nof_interface_calls_addr()); break;
964 case Bytecodes::_invokestatic:
965 case Bytecodes::_invokedynamic:
966 case Bytecodes::_invokespecial: increment_counter(SharedRuntime::nof_static_calls_addr()); break;
967 default: fatal("unexpected call bytecode");
968 }
969 }
970 }
971 }
972 #endif //PRODUCT
973
974
975 ciMethod* Compile::optimize_virtual_call(ciMethod* caller, int bci, ciInstanceKlass* klass,
976 ciKlass* holder, ciMethod* callee,
977 const TypeOopPtr* receiver_type, bool is_virtual,
978 bool& call_does_dispatch, int& vtable_index,
979 bool check_access) {
980 // Set default values for out-parameters.
981 call_does_dispatch = true;
982 vtable_index = Method::invalid_vtable_index;
983
984 // Choose call strategy.
985 ciMethod* optimized_virtual_method = optimize_inlining(caller, bci, klass, callee,
986 receiver_type, check_access);
987
988 // Have the call been sufficiently improved such that it is no longer a virtual?
989 if (optimized_virtual_method != NULL) {
990 callee = optimized_virtual_method;
991 call_does_dispatch = false;
992 } else if (!UseInlineCaches && is_virtual && callee->is_loaded()) {
993 // We can make a vtable call at this site
994 vtable_index = callee->resolve_vtable_index(caller->holder(), holder);
995 }
996 return callee;
997 }
998
999 // Identify possible target method and inlining style
1000 ciMethod* Compile::optimize_inlining(ciMethod* caller, int bci, ciInstanceKlass* klass,
1001 ciMethod* callee, const TypeOopPtr* receiver_type,
1002 bool check_access) {
1003 // only use for virtual or interface calls
1004
1005 // If it is obviously final, do not bother to call find_monomorphic_target,
1006 // because the class hierarchy checks are not needed, and may fail due to
1007 // incompletely loaded classes. Since we do our own class loading checks
1008 // in this module, we may confidently bind to any method.
1009 if (callee->can_be_statically_bound()) {
1010 return callee;
1011 }
1012
1013 // Attempt to improve the receiver
1014 bool actual_receiver_is_exact = false;
1015 ciInstanceKlass* actual_receiver = klass;
1016 if (receiver_type != NULL) {
1017 // Array methods are all inherited from Object, and are monomorphic.
1018 // finalize() call on array is not allowed.
1019 if (receiver_type->isa_aryptr() &&
1020 callee->holder() == env()->Object_klass() &&
1021 callee->name() != ciSymbol::finalize_method_name()) {
1022 return callee;
1023 }
1024
1025 // All other interesting cases are instance klasses.
1026 if (!receiver_type->isa_instptr()) {
1027 return NULL;
1028 }
1029
1030 ciInstanceKlass *ikl = receiver_type->klass()->as_instance_klass();
1031 if (ikl->is_loaded() && ikl->is_initialized() && !ikl->is_interface() &&
1032 (ikl == actual_receiver || ikl->is_subtype_of(actual_receiver))) {
1033 // ikl is a same or better type than the original actual_receiver,
1034 // e.g. static receiver from bytecodes.
1035 actual_receiver = ikl;
1036 // Is the actual_receiver exact?
1037 actual_receiver_is_exact = receiver_type->klass_is_exact();
1038 }
1039 }
1040
1041 ciInstanceKlass* calling_klass = caller->holder();
1042 ciMethod* cha_monomorphic_target = callee->find_monomorphic_target(calling_klass, klass, actual_receiver, check_access);
1043 if (cha_monomorphic_target != NULL) {
1044 assert(!cha_monomorphic_target->is_abstract(), "");
1045 // Look at the method-receiver type. Does it add "too much information"?
1046 ciKlass* mr_klass = cha_monomorphic_target->holder();
1047 const Type* mr_type = TypeInstPtr::make(TypePtr::BotPTR, mr_klass);
1048 if (receiver_type == NULL || !receiver_type->higher_equal(mr_type)) {
1049 // Calling this method would include an implicit cast to its holder.
1050 // %%% Not yet implemented. Would throw minor asserts at present.
1051 // %%% The most common wins are already gained by +UseUniqueSubclasses.
1052 // To fix, put the higher_equal check at the call of this routine,
1053 // and add a CheckCastPP to the receiver.
1054 if (TraceDependencies) {
1055 tty->print_cr("found unique CHA method, but could not cast up");
1056 tty->print(" method = ");
1057 cha_monomorphic_target->print();
1058 tty->cr();
1059 }
1060 if (log() != NULL) {
1061 log()->elem("missed_CHA_opportunity klass='%d' method='%d'",
1062 log()->identify(klass),
1063 log()->identify(cha_monomorphic_target));
1064 }
1065 cha_monomorphic_target = NULL;
1066 }
1067 }
1068 if (cha_monomorphic_target != NULL) {
1069 // Hardwiring a virtual.
1070 // If we inlined because CHA revealed only a single target method,
1071 // then we are dependent on that target method not getting overridden
1072 // by dynamic class loading. Be sure to test the "static" receiver
1073 // dest_method here, as opposed to the actual receiver, which may
1074 // falsely lead us to believe that the receiver is final or private.
1075 dependencies()->assert_unique_concrete_method(actual_receiver, cha_monomorphic_target);
1076 return cha_monomorphic_target;
1077 }
1078
1079 // If the type is exact, we can still bind the method w/o a vcall.
1080 // (This case comes after CHA so we can see how much extra work it does.)
1081 if (actual_receiver_is_exact) {
1082 // In case of evolution, there is a dependence on every inlined method, since each
1083 // such method can be changed when its class is redefined.
1084 ciMethod* exact_method = callee->resolve_invoke(calling_klass, actual_receiver);
1085 if (exact_method != NULL) {
1086 if (PrintOpto) {
1087 tty->print(" Calling method via exact type @%d --- ", bci);
1088 exact_method->print_name();
1089 tty->cr();
1090 }
1091 return exact_method;
1092 }
1093 }
1094
1095 return NULL;
1096 }