1 /*
2 * Copyright (c) 1998, 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 "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 #ifndef _LP64
85 // Check and handle overflow condition
86 if (profile.count() < -1) {
87 profile.set_count(max_jint);
88 }
89 #endif
90 // See how many times this site has been invoked.
91 int site_count = profile.count();
92 int receiver_count = -1;
93 if (call_does_dispatch && UseTypeProfile && profile.has_receiver(0)) {
94 // Receivers in the profile structure are ordered by call counts
95 // so that the most called (major) receiver is profile.receiver(0).
96 receiver_count = profile.receiver_count(0);
97 }
98
99 CompileLog* log = this->log();
100 if (log != NULL) {
101 int rid = (receiver_count >= 0)? log->identify(profile.receiver(0)): -1;
102 int r2id = (rid != -1 && profile.has_receiver(1))? log->identify(profile.receiver(1)):-1;
103 log->begin_elem("call method='%d' count='%d' prof_factor='%f'",
104 log->identify(callee), site_count, prof_factor);
105 if (call_does_dispatch) log->print(" virtual='1'");
106 if (allow_inline) log->print(" inline='1'");
107 if (receiver_count >= 0) {
108 log->print(" receiver='%d' receiver_count='%d'", rid, receiver_count);
109 if (profile.has_receiver(1)) {
110 log->print(" receiver2='%d' receiver2_count='%d'", r2id, profile.receiver_count(1));
111 }
112 }
113 if (callee->is_method_handle_intrinsic()) {
114 log->print(" method_handle_intrinsic='1'");
115 }
116 log->end_elem();
117 }
118
119 // Special case the handling of certain common, profitable library
120 // methods. If these methods are replaced with specialized code,
121 // then we return it as the inlined version of the call.
122 // We do this before the strict f.p. check below because the
123 // intrinsics handle strict f.p. correctly.
124 CallGenerator* cg_intrinsic = NULL;
125 if (allow_inline && allow_intrinsics) {
126 CallGenerator* cg = find_intrinsic(callee, call_does_dispatch);
127 if (cg != NULL) {
128 if (cg->is_predicated()) {
129 // Code without intrinsic but, hopefully, inlined.
130 CallGenerator* inline_cg = this->call_generator(callee,
131 vtable_index, call_does_dispatch, jvms, allow_inline, prof_factor, speculative_receiver_type, false);
132 if (inline_cg != NULL) {
133 cg = CallGenerator::for_predicated_intrinsic(cg, inline_cg);
134 }
135 }
136
137 // If intrinsic does the virtual dispatch, we try to use the type profile
138 // first, and hopefully inline it as the regular virtual call below.
139 // We will retry the intrinsic if nothing had claimed it afterwards.
140 if (cg->does_virtual_dispatch()) {
141 cg_intrinsic = cg;
142 cg = NULL;
143 } else {
144 return cg;
145 }
146 }
147 }
148
149 // Do method handle calls.
150 // NOTE: This must happen before normal inlining logic below since
151 // MethodHandle.invoke* are native methods which obviously don't
152 // have bytecodes and so normal inlining fails.
153 if (callee->is_method_handle_intrinsic()) {
154 CallGenerator* cg = CallGenerator::for_method_handle_call(jvms, caller, callee, delayed_forbidden);
155 assert(cg == NULL || !delayed_forbidden || !cg->is_late_inline() || cg->is_mh_late_inline(), "unexpected CallGenerator");
156 return cg;
157 }
158
159 // Do not inline strict fp into non-strict code, or the reverse
160 if (caller->is_strict() ^ callee->is_strict()) {
161 allow_inline = false;
162 }
163
164 // Attempt to inline...
165 if (allow_inline) {
166 // The profile data is only partly attributable to this caller,
167 // scale back the call site information.
168 float past_uses = jvms->method()->scale_count(site_count, prof_factor);
169 // This is the number of times we expect the call code to be used.
170 float expected_uses = past_uses;
171
172 // Try inlining a bytecoded method:
173 if (!call_does_dispatch) {
174 InlineTree* ilt = InlineTree::find_subtree_from_root(this->ilt(), jvms->caller(), jvms->method());
175 WarmCallInfo scratch_ci;
176 bool should_delay = false;
177 WarmCallInfo* ci = ilt->ok_to_inline(callee, jvms, profile, &scratch_ci, should_delay);
178 assert(ci != &scratch_ci, "do not let this pointer escape");
179 bool allow_inline = (ci != NULL && !ci->is_cold());
180 bool require_inline = (allow_inline && ci->is_hot());
181
182 if (allow_inline) {
183 CallGenerator* cg = CallGenerator::for_inline(callee, expected_uses);
184
185 if (require_inline && cg != NULL) {
186 // Delay the inlining of this method to give us the
187 // opportunity to perform some high level optimizations
188 // first.
189 if (should_delay_string_inlining(callee, jvms)) {
190 assert(!delayed_forbidden, "strange");
191 return CallGenerator::for_string_late_inline(callee, cg);
192 } else if (should_delay_boxing_inlining(callee, jvms)) {
193 assert(!delayed_forbidden, "strange");
194 return CallGenerator::for_boxing_late_inline(callee, cg);
195 } else if ((should_delay || AlwaysIncrementalInline) && !delayed_forbidden) {
196 return CallGenerator::for_late_inline(callee, cg);
197 }
198 }
199 if (cg == NULL || should_delay) {
200 // Fall through.
201 } else if (require_inline || !InlineWarmCalls) {
202 return cg;
203 } else {
204 CallGenerator* cold_cg = call_generator(callee, vtable_index, call_does_dispatch, jvms, false, prof_factor);
205 return CallGenerator::for_warm_call(ci, cold_cg, cg);
206 }
207 }
208 }
209
210 // Try using the type profile.
211 if (call_does_dispatch && site_count > 0 && UseTypeProfile) {
212 // The major receiver's count >= TypeProfileMajorReceiverPercent of site_count.
213 bool have_major_receiver = profile.has_receiver(0) && (100.*profile.receiver_prob(0) >= (float)TypeProfileMajorReceiverPercent);
214 ciMethod* receiver_method = NULL;
215
216 int morphism = profile.morphism();
217 if (speculative_receiver_type != NULL) {
218 if (!too_many_traps_or_recompiles(caller, bci, Deoptimization::Reason_speculate_class_check)) {
219 // We have a speculative type, we should be able to resolve
220 // the call. We do that before looking at the profiling at
221 // this invoke because it may lead to bimorphic inlining which
222 // a speculative type should help us avoid.
223 receiver_method = callee->resolve_invoke(jvms->method()->holder(),
224 speculative_receiver_type);
225 if (receiver_method == NULL) {
226 speculative_receiver_type = NULL;
227 } else {
228 morphism = 1;
229 }
230 } else {
231 // speculation failed before. Use profiling at the call
232 // (could allow bimorphic inlining for instance).
233 speculative_receiver_type = NULL;
234 }
235 }
236 if (receiver_method == NULL &&
237 (have_major_receiver || morphism == 1 ||
238 (morphism == 2 && UseBimorphicInlining))) {
239 // receiver_method = profile.method();
240 // Profiles do not suggest methods now. Look it up in the major receiver.
241 receiver_method = callee->resolve_invoke(jvms->method()->holder(),
242 profile.receiver(0));
243 }
244 if (receiver_method != NULL) {
245 // The single majority receiver sufficiently outweighs the minority.
246 CallGenerator* hit_cg = this->call_generator(receiver_method,
247 vtable_index, !call_does_dispatch, jvms, allow_inline, prof_factor);
248 if (hit_cg != NULL) {
249 // Look up second receiver.
250 CallGenerator* next_hit_cg = NULL;
251 ciMethod* next_receiver_method = NULL;
252 if (morphism == 2 && UseBimorphicInlining) {
253 next_receiver_method = callee->resolve_invoke(jvms->method()->holder(),
254 profile.receiver(1));
255 if (next_receiver_method != NULL) {
256 next_hit_cg = this->call_generator(next_receiver_method,
257 vtable_index, !call_does_dispatch, jvms,
258 allow_inline, prof_factor);
259 if (next_hit_cg != NULL && !next_hit_cg->is_inline() &&
260 have_major_receiver && UseOnlyInlinedBimorphic) {
261 // Skip if we can't inline second receiver's method
262 next_hit_cg = NULL;
263 }
264 }
265 }
266 CallGenerator* miss_cg;
267 Deoptimization::DeoptReason reason = (morphism == 2
268 ? Deoptimization::Reason_bimorphic
269 : Deoptimization::reason_class_check(speculative_receiver_type != NULL));
270 if ((morphism == 1 || (morphism == 2 && next_hit_cg != NULL)) &&
271 !too_many_traps_or_recompiles(caller, bci, reason)
272 ) {
273 // Generate uncommon trap for class check failure path
274 // in case of monomorphic or bimorphic virtual call site.
275 miss_cg = CallGenerator::for_uncommon_trap(callee, reason,
276 Deoptimization::Action_maybe_recompile);
277 } else {
278 // Generate virtual call for class check failure path
279 // in case of polymorphic virtual call site.
280 miss_cg = CallGenerator::for_virtual_call(callee, vtable_index);
281 }
282 if (miss_cg != NULL) {
283 if (next_hit_cg != NULL) {
284 assert(speculative_receiver_type == NULL, "shouldn't end up here if we used speculation");
285 trace_type_profile(C, jvms->method(), jvms->depth() - 1, jvms->bci(), next_receiver_method, profile.receiver(1), site_count, profile.receiver_count(1));
286 // We don't need to record dependency on a receiver here and below.
287 // Whenever we inline, the dependency is added by Parse::Parse().
288 miss_cg = CallGenerator::for_predicted_call(profile.receiver(1), miss_cg, next_hit_cg, PROB_MAX);
289 }
290 if (miss_cg != NULL) {
291 ciKlass* k = speculative_receiver_type != NULL ? speculative_receiver_type : profile.receiver(0);
292 trace_type_profile(C, jvms->method(), jvms->depth() - 1, jvms->bci(), receiver_method, k, site_count, receiver_count);
293 float hit_prob = speculative_receiver_type != NULL ? 1.0 : profile.receiver_prob(0);
294 CallGenerator* cg = CallGenerator::for_predicted_call(k, miss_cg, hit_cg, hit_prob);
295 if (cg != NULL) return cg;
296 }
297 }
298 }
299 }
300 }
301
302 // If there is only one implementor of this interface then we
303 // may be able to bind this invoke directly to the implementing
304 // klass but we need both a dependence on the single interface
305 // and on the method we bind to. Additionally since all we know
306 // about the receiver type is that it's supposed to implement the
307 // interface we have to insert a check that it's the class we
308 // expect. Interface types are not checked by the verifier so
309 // they are roughly equivalent to Object.
310 // The number of implementors for declared_interface is less or
311 // equal to the number of implementors for target->holder() so
312 // if number of implementors of target->holder() == 1 then
313 // number of implementors for decl_interface is 0 or 1. If
314 // it's 0 then no class implements decl_interface and there's
315 // no point in inlining.
316 if (call_does_dispatch && bytecode == Bytecodes::_invokeinterface) {
317 ciInstanceKlass* declared_interface =
318 caller->get_declared_method_holder_at_bci(bci)->as_instance_klass();
319
320 if (declared_interface->nof_implementors() == 1 &&
321 (!callee->is_default_method() || callee->is_overpass()) /* CHA doesn't support default methods yet */) {
322 ciInstanceKlass* singleton = declared_interface->implementor();
323 ciMethod* cha_monomorphic_target =
324 callee->find_monomorphic_target(caller->holder(), declared_interface, singleton);
325
326 if (cha_monomorphic_target != NULL &&
327 cha_monomorphic_target->holder() != env()->Object_klass()) { // subtype check against Object is useless
328 ciKlass* holder = cha_monomorphic_target->holder();
329
330 // Try to inline the method found by CHA. Inlined method is guarded by the type check.
331 CallGenerator* hit_cg = call_generator(cha_monomorphic_target,
332 vtable_index, !call_does_dispatch, jvms, allow_inline, prof_factor);
333
334 // Deoptimize on type check fail. The interpreter will throw ICCE for us.
335 CallGenerator* miss_cg = CallGenerator::for_uncommon_trap(callee,
336 Deoptimization::Reason_class_check, Deoptimization::Action_none);
337
338 CallGenerator* cg = CallGenerator::for_guarded_call(holder, miss_cg, hit_cg);
339 if (hit_cg != NULL && cg != NULL) {
340 dependencies()->assert_unique_concrete_method(declared_interface, cha_monomorphic_target);
341 return cg;
342 }
343 }
344 }
345 }
346 }
347
348 // Nothing claimed the intrinsic, we go with straight-forward inlining
349 // for already discovered intrinsic.
350 if (allow_inline && allow_intrinsics && cg_intrinsic != NULL) {
351 assert(cg_intrinsic->does_virtual_dispatch(), "sanity");
352 return cg_intrinsic;
353 }
354
355 // There was no special inlining tactic, or it bailed out.
356 // Use a more generic tactic, like a simple call.
357 if (call_does_dispatch) {
358 const char* msg = "virtual call";
359 if (PrintInlining) print_inlining(callee, jvms->depth() - 1, jvms->bci(), msg);
360 C->log_inline_failure(msg);
361 return CallGenerator::for_virtual_call(callee, vtable_index);
362 } else {
363 // Class Hierarchy Analysis or Type Profile reveals a unique target,
364 // or it is a static or special call.
365 return CallGenerator::for_direct_call(callee, should_delay_inlining(callee, jvms));
366 }
367 }
368
369 // Return true for methods that shouldn't be inlined early so that
370 // they are easier to analyze and optimize as intrinsics.
371 bool Compile::should_delay_string_inlining(ciMethod* call_method, JVMState* jvms) {
372 if (has_stringbuilder()) {
373
374 if ((call_method->holder() == C->env()->StringBuilder_klass() ||
375 call_method->holder() == C->env()->StringBuffer_klass()) &&
376 (jvms->method()->holder() == C->env()->StringBuilder_klass() ||
377 jvms->method()->holder() == C->env()->StringBuffer_klass())) {
378 // Delay SB calls only when called from non-SB code
379 return false;
380 }
381
382 switch (call_method->intrinsic_id()) {
383 case vmIntrinsics::_StringBuilder_void:
384 case vmIntrinsics::_StringBuilder_int:
385 case vmIntrinsics::_StringBuilder_String:
386 case vmIntrinsics::_StringBuilder_append_char:
387 case vmIntrinsics::_StringBuilder_append_int:
388 case vmIntrinsics::_StringBuilder_append_String:
389 case vmIntrinsics::_StringBuilder_toString:
390 case vmIntrinsics::_StringBuffer_void:
391 case vmIntrinsics::_StringBuffer_int:
392 case vmIntrinsics::_StringBuffer_String:
393 case vmIntrinsics::_StringBuffer_append_char:
394 case vmIntrinsics::_StringBuffer_append_int:
395 case vmIntrinsics::_StringBuffer_append_String:
396 case vmIntrinsics::_StringBuffer_toString:
397 case vmIntrinsics::_Integer_toString:
398 return true;
399
400 case vmIntrinsics::_String_String:
401 {
402 Node* receiver = jvms->map()->in(jvms->argoff() + 1);
403 if (receiver->is_Proj() && receiver->in(0)->is_CallStaticJava()) {
404 CallStaticJavaNode* csj = receiver->in(0)->as_CallStaticJava();
405 ciMethod* m = csj->method();
406 if (m != NULL &&
407 (m->intrinsic_id() == vmIntrinsics::_StringBuffer_toString ||
408 m->intrinsic_id() == vmIntrinsics::_StringBuilder_toString))
409 // Delay String.<init>(new SB())
410 return true;
411 }
412 return false;
413 }
414
415 default:
416 return false;
417 }
418 }
419 return false;
420 }
421
422 bool Compile::should_delay_boxing_inlining(ciMethod* call_method, JVMState* jvms) {
423 if (eliminate_boxing() && call_method->is_boxing_method()) {
424 set_has_boxed_value(true);
425 return aggressive_unboxing();
426 }
427 return false;
428 }
429
430 // uncommon-trap call-sites where callee is unloaded, uninitialized or will not link
431 bool Parse::can_not_compile_call_site(ciMethod *dest_method, ciInstanceKlass* klass) {
432 // Additional inputs to consider...
433 // bc = bc()
434 // caller = method()
435 // iter().get_method_holder_index()
436 assert( dest_method->is_loaded(), "ciTypeFlow should not let us get here" );
437 // Interface classes can be loaded & linked and never get around to
438 // being initialized. Uncommon-trap for not-initialized static or
439 // v-calls. Let interface calls happen.
440 ciInstanceKlass* holder_klass = dest_method->holder();
441 if (!holder_klass->is_being_initialized() &&
442 !holder_klass->is_initialized() &&
443 !holder_klass->is_interface()) {
444 uncommon_trap(Deoptimization::Reason_uninitialized,
445 Deoptimization::Action_reinterpret,
446 holder_klass);
447 return true;
448 }
449
450 assert(dest_method->is_loaded(), "dest_method: typeflow responsibility");
451 return false;
452 }
453
454 #ifdef ASSERT
455 static bool check_call_consistency(JVMState* jvms, CallGenerator* cg) {
456 ciMethod* symbolic_info = jvms->method()->get_method_at_bci(jvms->bci());
457 ciMethod* resolved_method = cg->method();
458 if (!ciMethod::is_consistent_info(symbolic_info, resolved_method)) {
459 tty->print_cr("JVMS:");
460 jvms->dump();
461 tty->print_cr("Bytecode info:");
462 jvms->method()->get_method_at_bci(jvms->bci())->print(); tty->cr();
463 tty->print_cr("Resolved method:");
464 cg->method()->print(); tty->cr();
465 return false;
466 }
467 return true;
468 }
469 #endif // ASSERT
470
471 //------------------------------do_call----------------------------------------
472 // Handle your basic call. Inline if we can & want to, else just setup call.
473 void Parse::do_call() {
474 // It's likely we are going to add debug info soon.
475 // Also, if we inline a guy who eventually needs debug info for this JVMS,
476 // our contribution to it is cleaned up right here.
477 kill_dead_locals();
478
479 C->print_inlining_assert_ready();
480
481 // Set frequently used booleans
482 const bool is_virtual = bc() == Bytecodes::_invokevirtual;
483 const bool is_virtual_or_interface = is_virtual || bc() == Bytecodes::_invokeinterface;
484 const bool has_receiver = Bytecodes::has_receiver(bc());
485
486 // Find target being called
487 bool will_link;
488 ciSignature* declared_signature = NULL;
489 ciMethod* orig_callee = iter().get_method(will_link, &declared_signature); // callee in the bytecode
490 ciInstanceKlass* holder_klass = orig_callee->holder();
491 ciKlass* holder = iter().get_declared_method_holder();
492 ciInstanceKlass* klass = ciEnv::get_instance_klass_for_declared_method_holder(holder);
493 assert(declared_signature != NULL, "cannot be null");
494
495 // Bump max node limit for JSR292 users
496 if (bc() == Bytecodes::_invokedynamic || orig_callee->is_method_handle_intrinsic()) {
497 C->set_max_node_limit(3*MaxNodeLimit);
498 }
499
500 // uncommon-trap when callee is unloaded, uninitialized or will not link
501 // bailout when too many arguments for register representation
502 if (!will_link || can_not_compile_call_site(orig_callee, klass)) {
503 if (PrintOpto && (Verbose || WizardMode)) {
504 method()->print_name(); tty->print_cr(" can not compile call at bci %d to:", bci());
505 orig_callee->print_name(); tty->cr();
506 }
507 return;
508 }
509 assert(holder_klass->is_loaded(), "");
510 //assert((bc_callee->is_static() || is_invokedynamic) == !has_receiver , "must match bc"); // XXX invokehandle (cur_bc_raw)
511 // Note: this takes into account invokeinterface of methods declared in java/lang/Object,
512 // which should be invokevirtuals but according to the VM spec may be invokeinterfaces
513 assert(holder_klass->is_interface() || holder_klass->super() == NULL || (bc() != Bytecodes::_invokeinterface), "must match bc");
514 // Note: In the absence of miranda methods, an abstract class K can perform
515 // an invokevirtual directly on an interface method I.m if K implements I.
516
517 // orig_callee is the resolved callee which's signature includes the
518 // appendix argument.
519 const int nargs = orig_callee->arg_size();
520 const bool is_signature_polymorphic = MethodHandles::is_signature_polymorphic(orig_callee->intrinsic_id());
521
522 // Push appendix argument (MethodType, CallSite, etc.), if one.
523 if (iter().has_appendix()) {
524 ciObject* appendix_arg = iter().get_appendix();
525 const TypeOopPtr* appendix_arg_type = TypeOopPtr::make_from_constant(appendix_arg, /* require_const= */ true);
526 Node* appendix_arg_node = _gvn.makecon(appendix_arg_type);
527 push(appendix_arg_node);
528 }
529
530 // ---------------------
531 // Does Class Hierarchy Analysis reveal only a single target of a v-call?
532 // Then we may inline or make a static call, but become dependent on there being only 1 target.
533 // Does the call-site type profile reveal only one receiver?
534 // Then we may introduce a run-time check and inline on the path where it succeeds.
535 // The other path may uncommon_trap, check for another receiver, or do a v-call.
536
537 // Try to get the most accurate receiver type
538 ciMethod* callee = orig_callee;
539 int vtable_index = Method::invalid_vtable_index;
540 bool call_does_dispatch = false;
541
542 // Speculative type of the receiver if any
543 ciKlass* speculative_receiver_type = NULL;
544 if (is_virtual_or_interface) {
545 Node* receiver_node = stack(sp() - nargs);
546 const TypeOopPtr* receiver_type = _gvn.type(receiver_node)->isa_oopptr();
547 // call_does_dispatch and vtable_index are out-parameters. They might be changed.
548 // For arrays, klass below is Object. When vtable calls are used,
549 // resolving the call with Object would allow an illegal call to
550 // finalize() on an array. We use holder instead: illegal calls to
551 // finalize() won't be compiled as vtable calls (IC call
552 // resolution will catch the illegal call) and the few legal calls
553 // on array types won't be either.
554 callee = C->optimize_virtual_call(method(), bci(), klass, holder, orig_callee,
555 receiver_type, is_virtual,
556 call_does_dispatch, vtable_index); // out-parameters
557 speculative_receiver_type = receiver_type != NULL ? receiver_type->speculative_type() : NULL;
558 }
559
560 // Additional receiver subtype checks for interface calls via invokespecial or invokeinterface.
561 ciKlass* receiver_constraint = NULL;
562 if (iter().cur_bc_raw() == Bytecodes::_invokespecial && !orig_callee->is_object_initializer()) {
563 ciInstanceKlass* calling_klass = method()->holder();
564 ciInstanceKlass* sender_klass =
565 calling_klass->is_unsafe_anonymous() ? calling_klass->unsafe_anonymous_host() :
566 calling_klass;
567 if (sender_klass->is_interface()) {
568 receiver_constraint = sender_klass;
569 }
570 } else if (iter().cur_bc_raw() == Bytecodes::_invokeinterface && orig_callee->is_private()) {
571 assert(holder->is_interface(), "How did we get a non-interface method here!");
572 receiver_constraint = holder;
573 }
574
575 if (receiver_constraint != NULL) {
576 Node* receiver_node = stack(sp() - nargs);
577 Node* cls_node = makecon(TypeKlassPtr::make(receiver_constraint));
578 Node* bad_type_ctrl = NULL;
579 Node* casted_receiver = gen_checkcast(receiver_node, cls_node, &bad_type_ctrl);
580 if (bad_type_ctrl != NULL) {
581 PreserveJVMState pjvms(this);
582 set_control(bad_type_ctrl);
583 uncommon_trap(Deoptimization::Reason_class_check,
584 Deoptimization::Action_none);
585 }
586 if (stopped()) {
587 return; // MUST uncommon-trap?
588 }
589 set_stack(sp() - nargs, casted_receiver);
590 }
591
592 // Note: It's OK to try to inline a virtual call.
593 // The call generator will not attempt to inline a polymorphic call
594 // unless it knows how to optimize the receiver dispatch.
595 bool try_inline = (C->do_inlining() || InlineAccessors);
596
597 // ---------------------
598 dec_sp(nargs); // Temporarily pop args for JVM state of call
599 JVMState* jvms = sync_jvms();
600
601 // ---------------------
602 // Decide call tactic.
603 // This call checks with CHA, the interpreter profile, intrinsics table, etc.
604 // It decides whether inlining is desirable or not.
605 CallGenerator* cg = C->call_generator(callee, vtable_index, call_does_dispatch, jvms, try_inline, prof_factor(), speculative_receiver_type);
606
607 // NOTE: Don't use orig_callee and callee after this point! Use cg->method() instead.
608 orig_callee = callee = NULL;
609
610 // ---------------------
611 // Round double arguments before call
612 round_double_arguments(cg->method());
613
614 // Feed profiling data for arguments to the type system so it can
615 // propagate it as speculative types
616 record_profiled_arguments_for_speculation(cg->method(), bc());
617
618 #ifndef PRODUCT
619 // bump global counters for calls
620 count_compiled_calls(/*at_method_entry*/ false, cg->is_inline());
621
622 // Record first part of parsing work for this call
623 parse_histogram()->record_change();
624 #endif // not PRODUCT
625
626 assert(jvms == this->jvms(), "still operating on the right JVMS");
627 assert(jvms_in_sync(), "jvms must carry full info into CG");
628
629 // save across call, for a subsequent cast_not_null.
630 Node* receiver = has_receiver ? argument(0) : NULL;
631
632 // The extra CheckCastPPs for speculative types mess with PhaseStringOpts
633 if (receiver != NULL && !call_does_dispatch && !cg->is_string_late_inline()) {
634 // Feed profiling data for a single receiver to the type system so
635 // it can propagate it as a speculative type
636 receiver = record_profiled_receiver_for_speculation(receiver);
637 }
638
639 // Bump method data counters (We profile *before* the call is made
640 // because exceptions don't return to the call site.)
641 profile_call(receiver);
642
643 JVMState* new_jvms = cg->generate(jvms);
644 if (new_jvms == NULL) {
645 // When inlining attempt fails (e.g., too many arguments),
646 // it may contaminate the current compile state, making it
647 // impossible to pull back and try again. Once we call
648 // cg->generate(), we are committed. If it fails, the whole
649 // compilation task is compromised.
650 if (failing()) return;
651
652 // This can happen if a library intrinsic is available, but refuses
653 // the call site, perhaps because it did not match a pattern the
654 // intrinsic was expecting to optimize. Should always be possible to
655 // get a normal java call that may inline in that case
656 cg = C->call_generator(cg->method(), vtable_index, call_does_dispatch, jvms, try_inline, prof_factor(), speculative_receiver_type, /* allow_intrinsics= */ false);
657 new_jvms = cg->generate(jvms);
658 if (new_jvms == NULL) {
659 guarantee(failing(), "call failed to generate: calls should work");
660 return;
661 }
662 }
663
664 if (cg->is_inline()) {
665 // Accumulate has_loops estimate
666 C->set_has_loops(C->has_loops() || cg->method()->has_loops());
667 C->env()->notice_inlined_method(cg->method());
668 }
669
670 // Reset parser state from [new_]jvms, which now carries results of the call.
671 // Return value (if any) is already pushed on the stack by the cg.
672 add_exception_states_from(new_jvms);
673 if (new_jvms->map()->control() == top()) {
674 stop_and_kill_map();
675 } else {
676 assert(new_jvms->same_calls_as(jvms), "method/bci left unchanged");
677 set_jvms(new_jvms);
678 }
679
680 assert(check_call_consistency(jvms, cg), "inconsistent info");
681
682 if (!stopped()) {
683 // This was some sort of virtual call, which did a null check for us.
684 // Now we can assert receiver-not-null, on the normal return path.
685 if (receiver != NULL && cg->is_virtual()) {
686 Node* cast = cast_not_null(receiver);
687 // %%% assert(receiver == cast, "should already have cast the receiver");
688 }
689
690 // Round double result after a call from strict to non-strict code
691 round_double_result(cg->method());
692
693 ciType* rtype = cg->method()->return_type();
694 ciType* ctype = declared_signature->return_type();
695
696 if (Bytecodes::has_optional_appendix(iter().cur_bc_raw()) || is_signature_polymorphic) {
697 // Be careful here with return types.
698 if (ctype != rtype) {
699 BasicType rt = rtype->basic_type();
700 BasicType ct = ctype->basic_type();
701 if (ct == T_VOID) {
702 // It's OK for a method to return a value that is discarded.
703 // The discarding does not require any special action from the caller.
704 // The Java code knows this, at VerifyType.isNullConversion.
705 pop_node(rt); // whatever it was, pop it
706 } else if (rt == T_INT || is_subword_type(rt)) {
707 // Nothing. These cases are handled in lambda form bytecode.
708 assert(ct == T_INT || is_subword_type(ct), "must match: rt=%s, ct=%s", type2name(rt), type2name(ct));
709 } else if (rt == T_OBJECT || rt == T_ARRAY) {
710 assert(ct == T_OBJECT || ct == T_ARRAY, "rt=%s, ct=%s", type2name(rt), type2name(ct));
711 if (ctype->is_loaded()) {
712 const TypeOopPtr* arg_type = TypeOopPtr::make_from_klass(rtype->as_klass());
713 const Type* sig_type = TypeOopPtr::make_from_klass(ctype->as_klass());
714 if (arg_type != NULL && !arg_type->higher_equal(sig_type)) {
715 Node* retnode = pop();
716 Node* cast_obj = _gvn.transform(new CheckCastPPNode(control(), retnode, sig_type));
717 push(cast_obj);
718 }
719 }
720 } else {
721 assert(rt == ct, "unexpected mismatch: rt=%s, ct=%s", type2name(rt), type2name(ct));
722 // push a zero; it's better than getting an oop/int mismatch
723 pop_node(rt);
724 Node* retnode = zerocon(ct);
725 push_node(ct, retnode);
726 }
727 // Now that the value is well-behaved, continue with the call-site type.
728 rtype = ctype;
729 }
730 } else {
731 // Symbolic resolution enforces the types to be the same.
732 // NOTE: We must relax the assert for unloaded types because two
733 // different ciType instances of the same unloaded class type
734 // can appear to be "loaded" by different loaders (depending on
735 // the accessing class).
736 assert(!rtype->is_loaded() || !ctype->is_loaded() || rtype == ctype,
737 "mismatched return types: rtype=%s, ctype=%s", rtype->name(), ctype->name());
738 }
739
740 // If the return type of the method is not loaded, assert that the
741 // value we got is a null. Otherwise, we need to recompile.
742 if (!rtype->is_loaded()) {
743 if (PrintOpto && (Verbose || WizardMode)) {
744 method()->print_name(); tty->print_cr(" asserting nullness of result at bci: %d", bci());
745 cg->method()->print_name(); tty->cr();
746 }
747 if (C->log() != NULL) {
748 C->log()->elem("assert_null reason='return' klass='%d'",
749 C->log()->identify(rtype));
750 }
751 // If there is going to be a trap, put it at the next bytecode:
752 set_bci(iter().next_bci());
753 null_assert(peek());
754 set_bci(iter().cur_bci()); // put it back
755 }
756 BasicType ct = ctype->basic_type();
757 if (ct == T_OBJECT || ct == T_ARRAY) {
758 record_profiled_return_for_speculation();
759 }
760 }
761
762 // Restart record of parsing work after possible inlining of call
763 #ifndef PRODUCT
764 parse_histogram()->set_initial_state(bc());
765 #endif
766 }
767
768 //---------------------------catch_call_exceptions-----------------------------
769 // Put a Catch and CatchProj nodes behind a just-created call.
770 // Send their caught exceptions to the proper handler.
771 // This may be used after a call to the rethrow VM stub,
772 // when it is needed to process unloaded exception classes.
773 void Parse::catch_call_exceptions(ciExceptionHandlerStream& handlers) {
774 // Exceptions are delivered through this channel:
775 Node* i_o = this->i_o();
776
777 // Add a CatchNode.
778 GrowableArray<int>* bcis = new (C->node_arena()) GrowableArray<int>(C->node_arena(), 8, 0, -1);
779 GrowableArray<const Type*>* extypes = new (C->node_arena()) GrowableArray<const Type*>(C->node_arena(), 8, 0, NULL);
780 GrowableArray<int>* saw_unloaded = new (C->node_arena()) GrowableArray<int>(C->node_arena(), 8, 0, 0);
781
782 bool default_handler = false;
783 for (; !handlers.is_done(); handlers.next()) {
784 ciExceptionHandler* h = handlers.handler();
785 int h_bci = h->handler_bci();
786 ciInstanceKlass* h_klass = h->is_catch_all() ? env()->Throwable_klass() : h->catch_klass();
787 // Do not introduce unloaded exception types into the graph:
788 if (!h_klass->is_loaded()) {
789 if (saw_unloaded->contains(h_bci)) {
790 /* We've already seen an unloaded exception with h_bci,
791 so don't duplicate. Duplication will cause the CatchNode to be
792 unnecessarily large. See 4713716. */
793 continue;
794 } else {
795 saw_unloaded->append(h_bci);
796 }
797 }
798 const Type* h_extype = TypeOopPtr::make_from_klass(h_klass);
799 // (We use make_from_klass because it respects UseUniqueSubclasses.)
800 h_extype = h_extype->join(TypeInstPtr::NOTNULL);
801 assert(!h_extype->empty(), "sanity");
802 // Note: It's OK if the BCIs repeat themselves.
803 bcis->append(h_bci);
804 extypes->append(h_extype);
805 if (h_bci == -1) {
806 default_handler = true;
807 }
808 }
809
810 if (!default_handler) {
811 bcis->append(-1);
812 extypes->append(TypeOopPtr::make_from_klass(env()->Throwable_klass())->is_instptr());
813 }
814
815 int len = bcis->length();
816 CatchNode *cn = new CatchNode(control(), i_o, len+1);
817 Node *catch_ = _gvn.transform(cn);
818
819 // now branch with the exception state to each of the (potential)
820 // handlers
821 for(int i=0; i < len; i++) {
822 // Setup JVM state to enter the handler.
823 PreserveJVMState pjvms(this);
824 // Locals are just copied from before the call.
825 // Get control from the CatchNode.
826 int handler_bci = bcis->at(i);
827 Node* ctrl = _gvn.transform( new CatchProjNode(catch_, i+1,handler_bci));
828 // This handler cannot happen?
829 if (ctrl == top()) continue;
830 set_control(ctrl);
831
832 // Create exception oop
833 const TypeInstPtr* extype = extypes->at(i)->is_instptr();
834 Node *ex_oop = _gvn.transform(new CreateExNode(extypes->at(i), ctrl, i_o));
835
836 // Handle unloaded exception classes.
837 if (saw_unloaded->contains(handler_bci)) {
838 // An unloaded exception type is coming here. Do an uncommon trap.
839 #ifndef PRODUCT
840 // We do not expect the same handler bci to take both cold unloaded
841 // and hot loaded exceptions. But, watch for it.
842 if ((Verbose || WizardMode) && extype->is_loaded()) {
843 tty->print("Warning: Handler @%d takes mixed loaded/unloaded exceptions in ", bci());
844 method()->print_name(); tty->cr();
845 } else if (PrintOpto && (Verbose || WizardMode)) {
846 tty->print("Bailing out on unloaded exception type ");
847 extype->klass()->print_name();
848 tty->print(" at bci:%d in ", bci());
849 method()->print_name(); tty->cr();
850 }
851 #endif
852 // Emit an uncommon trap instead of processing the block.
853 set_bci(handler_bci);
854 push_ex_oop(ex_oop);
855 uncommon_trap(Deoptimization::Reason_unloaded,
856 Deoptimization::Action_reinterpret,
857 extype->klass(), "!loaded exception");
858 set_bci(iter().cur_bci()); // put it back
859 continue;
860 }
861
862 // go to the exception handler
863 if (handler_bci < 0) { // merge with corresponding rethrow node
864 throw_to_exit(make_exception_state(ex_oop));
865 } else { // Else jump to corresponding handle
866 push_ex_oop(ex_oop); // Clear stack and push just the oop.
867 merge_exception(handler_bci);
868 }
869 }
870
871 // The first CatchProj is for the normal return.
872 // (Note: If this is a call to rethrow_Java, this node goes dead.)
873 set_control(_gvn.transform( new CatchProjNode(catch_, CatchProjNode::fall_through_index, CatchProjNode::no_handler_bci)));
874 }
875
876
877 //----------------------------catch_inline_exceptions--------------------------
878 // Handle all exceptions thrown by an inlined method or individual bytecode.
879 // Common case 1: we have no handler, so all exceptions merge right into
880 // the rethrow case.
881 // Case 2: we have some handlers, with loaded exception klasses that have
882 // no subklasses. We do a Deutsch-Shiffman style type-check on the incoming
883 // exception oop and branch to the handler directly.
884 // Case 3: We have some handlers with subklasses or are not loaded at
885 // compile-time. We have to call the runtime to resolve the exception.
886 // So we insert a RethrowCall and all the logic that goes with it.
887 void Parse::catch_inline_exceptions(SafePointNode* ex_map) {
888 // Caller is responsible for saving away the map for normal control flow!
889 assert(stopped(), "call set_map(NULL) first");
890 assert(method()->has_exception_handlers(), "don't come here w/o work to do");
891
892 Node* ex_node = saved_ex_oop(ex_map);
893 if (ex_node == top()) {
894 // No action needed.
895 return;
896 }
897 const TypeInstPtr* ex_type = _gvn.type(ex_node)->isa_instptr();
898 NOT_PRODUCT(if (ex_type==NULL) tty->print_cr("*** Exception not InstPtr"));
899 if (ex_type == NULL)
900 ex_type = TypeOopPtr::make_from_klass(env()->Throwable_klass())->is_instptr();
901
902 // determine potential exception handlers
903 ciExceptionHandlerStream handlers(method(), bci(),
904 ex_type->klass()->as_instance_klass(),
905 ex_type->klass_is_exact());
906
907 // Start executing from the given throw state. (Keep its stack, for now.)
908 // Get the exception oop as known at compile time.
909 ex_node = use_exception_state(ex_map);
910
911 // Get the exception oop klass from its header
912 Node* ex_klass_node = NULL;
913 if (has_ex_handler() && !ex_type->klass_is_exact()) {
914 Node* p = basic_plus_adr( ex_node, ex_node, oopDesc::klass_offset_in_bytes());
915 ex_klass_node = _gvn.transform(LoadKlassNode::make(_gvn, NULL, immutable_memory(), p, TypeInstPtr::KLASS, TypeKlassPtr::OBJECT));
916
917 // Compute the exception klass a little more cleverly.
918 // Obvious solution is to simple do a LoadKlass from the 'ex_node'.
919 // However, if the ex_node is a PhiNode, I'm going to do a LoadKlass for
920 // each arm of the Phi. If I know something clever about the exceptions
921 // I'm loading the class from, I can replace the LoadKlass with the
922 // klass constant for the exception oop.
923 if (ex_node->is_Phi()) {
924 ex_klass_node = new PhiNode(ex_node->in(0), TypeKlassPtr::OBJECT);
925 for (uint i = 1; i < ex_node->req(); i++) {
926 Node* ex_in = ex_node->in(i);
927 if (ex_in == top() || ex_in == NULL) {
928 // This path was not taken.
929 ex_klass_node->init_req(i, top());
930 continue;
931 }
932 Node* p = basic_plus_adr(ex_in, ex_in, oopDesc::klass_offset_in_bytes());
933 Node* k = _gvn.transform( LoadKlassNode::make(_gvn, NULL, immutable_memory(), p, TypeInstPtr::KLASS, TypeKlassPtr::OBJECT));
934 ex_klass_node->init_req( i, k );
935 }
936 _gvn.set_type(ex_klass_node, TypeKlassPtr::OBJECT);
937
938 }
939 }
940
941 // Scan the exception table for applicable handlers.
942 // If none, we can call rethrow() and be done!
943 // If precise (loaded with no subklasses), insert a D.S. style
944 // pointer compare to the correct handler and loop back.
945 // If imprecise, switch to the Rethrow VM-call style handling.
946
947 int remaining = handlers.count_remaining();
948
949 // iterate through all entries sequentially
950 for (;!handlers.is_done(); handlers.next()) {
951 ciExceptionHandler* handler = handlers.handler();
952
953 if (handler->is_rethrow()) {
954 // If we fell off the end of the table without finding an imprecise
955 // exception klass (and without finding a generic handler) then we
956 // know this exception is not handled in this method. We just rethrow
957 // the exception into the caller.
958 throw_to_exit(make_exception_state(ex_node));
959 return;
960 }
961
962 // exception handler bci range covers throw_bci => investigate further
963 int handler_bci = handler->handler_bci();
964
965 if (remaining == 1) {
966 push_ex_oop(ex_node); // Push exception oop for handler
967 if (PrintOpto && WizardMode) {
968 tty->print_cr(" Catching every inline exception bci:%d -> handler_bci:%d", bci(), handler_bci);
969 }
970 merge_exception(handler_bci); // jump to handler
971 return; // No more handling to be done here!
972 }
973
974 // Get the handler's klass
975 ciInstanceKlass* klass = handler->catch_klass();
976
977 if (!klass->is_loaded()) { // klass is not loaded?
978 // fall through into catch_call_exceptions which will emit a
979 // handler with an uncommon trap.
980 break;
981 }
982
983 if (klass->is_interface()) // should not happen, but...
984 break; // bail out
985
986 // Check the type of the exception against the catch type
987 const TypeKlassPtr *tk = TypeKlassPtr::make(klass);
988 Node* con = _gvn.makecon(tk);
989 Node* not_subtype_ctrl = gen_subtype_check(ex_klass_node, con);
990 if (!stopped()) {
991 PreserveJVMState pjvms(this);
992 const TypeInstPtr* tinst = TypeOopPtr::make_from_klass_unique(klass)->cast_to_ptr_type(TypePtr::NotNull)->is_instptr();
993 assert(klass->has_subklass() || tinst->klass_is_exact(), "lost exactness");
994 Node* ex_oop = _gvn.transform(new CheckCastPPNode(control(), ex_node, tinst));
995 push_ex_oop(ex_oop); // Push exception oop for handler
996 if (PrintOpto && WizardMode) {
997 tty->print(" Catching inline exception bci:%d -> handler_bci:%d -- ", bci(), handler_bci);
998 klass->print_name();
999 tty->cr();
1000 }
1001 merge_exception(handler_bci);
1002 }
1003 set_control(not_subtype_ctrl);
1004
1005 // Come here if exception does not match handler.
1006 // Carry on with more handler checks.
1007 --remaining;
1008 }
1009
1010 assert(!stopped(), "you should return if you finish the chain");
1011
1012 // Oops, need to call into the VM to resolve the klasses at runtime.
1013 // Note: This call must not deoptimize, since it is not a real at this bci!
1014 kill_dead_locals();
1015
1016 make_runtime_call(RC_NO_LEAF | RC_MUST_THROW,
1017 OptoRuntime::rethrow_Type(),
1018 OptoRuntime::rethrow_stub(),
1019 NULL, NULL,
1020 ex_node);
1021
1022 // Rethrow is a pure call, no side effects, only a result.
1023 // The result cannot be allocated, so we use I_O
1024
1025 // Catch exceptions from the rethrow
1026 catch_call_exceptions(handlers);
1027 }
1028
1029
1030 // (Note: Moved add_debug_info into GraphKit::add_safepoint_edges.)
1031
1032
1033 #ifndef PRODUCT
1034 void Parse::count_compiled_calls(bool at_method_entry, bool is_inline) {
1035 if( CountCompiledCalls ) {
1036 if( at_method_entry ) {
1037 // bump invocation counter if top method (for statistics)
1038 if (CountCompiledCalls && depth() == 1) {
1039 const TypePtr* addr_type = TypeMetadataPtr::make(method());
1040 Node* adr1 = makecon(addr_type);
1041 Node* adr2 = basic_plus_adr(adr1, adr1, in_bytes(Method::compiled_invocation_counter_offset()));
1042 increment_counter(adr2);
1043 }
1044 } else if (is_inline) {
1045 switch (bc()) {
1046 case Bytecodes::_invokevirtual: increment_counter(SharedRuntime::nof_inlined_calls_addr()); break;
1047 case Bytecodes::_invokeinterface: increment_counter(SharedRuntime::nof_inlined_interface_calls_addr()); break;
1048 case Bytecodes::_invokestatic:
1049 case Bytecodes::_invokedynamic:
1050 case Bytecodes::_invokespecial: increment_counter(SharedRuntime::nof_inlined_static_calls_addr()); break;
1051 default: fatal("unexpected call bytecode");
1052 }
1053 } else {
1054 switch (bc()) {
1055 case Bytecodes::_invokevirtual: increment_counter(SharedRuntime::nof_normal_calls_addr()); break;
1056 case Bytecodes::_invokeinterface: increment_counter(SharedRuntime::nof_interface_calls_addr()); break;
1057 case Bytecodes::_invokestatic:
1058 case Bytecodes::_invokedynamic:
1059 case Bytecodes::_invokespecial: increment_counter(SharedRuntime::nof_static_calls_addr()); break;
1060 default: fatal("unexpected call bytecode");
1061 }
1062 }
1063 }
1064 }
1065 #endif //PRODUCT
1066
1067
1068 ciMethod* Compile::optimize_virtual_call(ciMethod* caller, int bci, ciInstanceKlass* klass,
1069 ciKlass* holder, ciMethod* callee,
1070 const TypeOopPtr* receiver_type, bool is_virtual,
1071 bool& call_does_dispatch, int& vtable_index,
1072 bool check_access) {
1073 // Set default values for out-parameters.
1074 call_does_dispatch = true;
1075 vtable_index = Method::invalid_vtable_index;
1076
1077 // Choose call strategy.
1078 ciMethod* optimized_virtual_method = optimize_inlining(caller, bci, klass, callee,
1079 receiver_type, check_access);
1080
1081 // Have the call been sufficiently improved such that it is no longer a virtual?
1082 if (optimized_virtual_method != NULL) {
1083 callee = optimized_virtual_method;
1084 call_does_dispatch = false;
1085 } else if (!UseInlineCaches && is_virtual && callee->is_loaded()) {
1086 // We can make a vtable call at this site
1087 vtable_index = callee->resolve_vtable_index(caller->holder(), holder);
1088 }
1089 return callee;
1090 }
1091
1092 // Identify possible target method and inlining style
1093 ciMethod* Compile::optimize_inlining(ciMethod* caller, int bci, ciInstanceKlass* klass,
1094 ciMethod* callee, const TypeOopPtr* receiver_type,
1095 bool check_access) {
1096 // only use for virtual or interface calls
1097
1098 // If it is obviously final, do not bother to call find_monomorphic_target,
1099 // because the class hierarchy checks are not needed, and may fail due to
1100 // incompletely loaded classes. Since we do our own class loading checks
1101 // in this module, we may confidently bind to any method.
1102 if (callee->can_be_statically_bound()) {
1103 return callee;
1104 }
1105
1106 // Attempt to improve the receiver
1107 bool actual_receiver_is_exact = false;
1108 ciInstanceKlass* actual_receiver = klass;
1109 if (receiver_type != NULL) {
1110 // Array methods are all inherited from Object, and are monomorphic.
1111 // finalize() call on array is not allowed.
1112 if (receiver_type->isa_aryptr() &&
1113 callee->holder() == env()->Object_klass() &&
1114 callee->name() != ciSymbol::finalize_method_name()) {
1115 return callee;
1116 }
1117
1118 // All other interesting cases are instance klasses.
1119 if (!receiver_type->isa_instptr()) {
1120 return NULL;
1121 }
1122
1123 ciInstanceKlass *ikl = receiver_type->klass()->as_instance_klass();
1124 if (ikl->is_loaded() && ikl->is_initialized() && !ikl->is_interface() &&
1125 (ikl == actual_receiver || ikl->is_subtype_of(actual_receiver))) {
1126 // ikl is a same or better type than the original actual_receiver,
1127 // e.g. static receiver from bytecodes.
1128 actual_receiver = ikl;
1129 // Is the actual_receiver exact?
1130 actual_receiver_is_exact = receiver_type->klass_is_exact();
1131 }
1132 }
1133
1134 ciInstanceKlass* calling_klass = caller->holder();
1135 ciMethod* cha_monomorphic_target = callee->find_monomorphic_target(calling_klass, klass, actual_receiver, check_access);
1136 if (cha_monomorphic_target != NULL) {
1137 assert(!cha_monomorphic_target->is_abstract(), "");
1138 // Look at the method-receiver type. Does it add "too much information"?
1139 ciKlass* mr_klass = cha_monomorphic_target->holder();
1140 const Type* mr_type = TypeInstPtr::make(TypePtr::BotPTR, mr_klass);
1141 if (receiver_type == NULL || !receiver_type->higher_equal(mr_type)) {
1142 // Calling this method would include an implicit cast to its holder.
1143 // %%% Not yet implemented. Would throw minor asserts at present.
1144 // %%% The most common wins are already gained by +UseUniqueSubclasses.
1145 // To fix, put the higher_equal check at the call of this routine,
1146 // and add a CheckCastPP to the receiver.
1147 if (TraceDependencies) {
1148 tty->print_cr("found unique CHA method, but could not cast up");
1149 tty->print(" method = ");
1150 cha_monomorphic_target->print();
1151 tty->cr();
1152 }
1153 if (log() != NULL) {
1154 log()->elem("missed_CHA_opportunity klass='%d' method='%d'",
1155 log()->identify(klass),
1156 log()->identify(cha_monomorphic_target));
1157 }
1158 cha_monomorphic_target = NULL;
1159 }
1160 }
1161
1162 if (cha_monomorphic_target != NULL) {
1163 // Hardwiring a virtual.
1164 assert(!callee->can_be_statically_bound(), "should have been handled earlier");
1165 assert(!cha_monomorphic_target->is_abstract(), "");
1166 if (!cha_monomorphic_target->can_be_statically_bound(actual_receiver)) {
1167 // If we inlined because CHA revealed only a single target method,
1168 // then we are dependent on that target method not getting overridden
1169 // by dynamic class loading. Be sure to test the "static" receiver
1170 // dest_method here, as opposed to the actual receiver, which may
1171 // falsely lead us to believe that the receiver is final or private.
1172 dependencies()->assert_unique_concrete_method(actual_receiver, cha_monomorphic_target);
1173 }
1174 return cha_monomorphic_target;
1175 }
1176
1177 // If the type is exact, we can still bind the method w/o a vcall.
1178 // (This case comes after CHA so we can see how much extra work it does.)
1179 if (actual_receiver_is_exact) {
1180 // In case of evolution, there is a dependence on every inlined method, since each
1181 // such method can be changed when its class is redefined.
1182 ciMethod* exact_method = callee->resolve_invoke(calling_klass, actual_receiver);
1183 if (exact_method != NULL) {
1184 if (PrintOpto) {
1185 tty->print(" Calling method via exact type @%d --- ", bci);
1186 exact_method->print_name();
1187 tty->cr();
1188 }
1189 return exact_method;
1190 }
1191 }
1192
1193 return NULL;
1194 }