1 /*
2 * Copyright (c) 1998, 2019, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "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) {
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 if (should_delay_vector_inlining(callee, jvms)) {
138 return CallGenerator::for_late_inline(callee, cg);
139 } else {
140 return cg;
141 }
142 }
143 }
144
145 // Do method handle calls.
146 // NOTE: This must happen before normal inlining logic below since
147 // MethodHandle.invoke* are native methods which obviously don't
148 // have bytecodes and so normal inlining fails.
149 if (callee->is_method_handle_intrinsic()) {
150 CallGenerator* cg = CallGenerator::for_method_handle_call(jvms, caller, callee);
151 return cg;
152 }
153
154 // If explicit rounding is required, do not inline strict into non-strict code (or the reverse).
155 if (Matcher::strict_fp_requires_explicit_rounding &&
156 caller->is_strict() != callee->is_strict()) {
157 allow_inline = false;
158 }
159
160 // Attempt to inline...
161 if (allow_inline) {
162 // The profile data is only partly attributable to this caller,
163 // scale back the call site information.
164 float past_uses = jvms->method()->scale_count(site_count, prof_factor);
165 // This is the number of times we expect the call code to be used.
166 float expected_uses = past_uses;
167
168 // Try inlining a bytecoded method:
169 if (!call_does_dispatch) {
170 InlineTree* ilt = InlineTree::find_subtree_from_root(this->ilt(), jvms->caller(), jvms->method());
171 WarmCallInfo scratch_ci;
172 bool should_delay = false;
173 WarmCallInfo* ci = ilt->ok_to_inline(callee, jvms, profile, &scratch_ci, should_delay);
174 assert(ci != &scratch_ci, "do not let this pointer escape");
175 bool allow_inline = (ci != NULL && !ci->is_cold());
176 bool require_inline = (allow_inline && ci->is_hot());
177
178 if (allow_inline) {
179 CallGenerator* cg = CallGenerator::for_inline(callee, expected_uses);
180
181 if (require_inline && cg != NULL) {
182 // Delay the inlining of this method to give us the
183 // opportunity to perform some high level optimizations
184 // first.
185 if (should_delay_string_inlining(callee, jvms)) {
186 return CallGenerator::for_string_late_inline(callee, cg);
187 } else if (should_delay_boxing_inlining(callee, jvms)) {
188 return CallGenerator::for_boxing_late_inline(callee, cg);
189 } else if (should_delay_vector_reboxing_inlining(callee, jvms)) {
190 return CallGenerator::for_vector_reboxing_late_inline(callee, cg);
191 } else if ((should_delay || AlwaysIncrementalInline)) {
192 return CallGenerator::for_late_inline(callee, cg);
193 }
194 }
195 if (cg == NULL || should_delay) {
196 // Fall through.
197 } else if (require_inline || !InlineWarmCalls) {
198 return cg;
199 } else {
200 CallGenerator* cold_cg = call_generator(callee, vtable_index, call_does_dispatch, jvms, false, prof_factor);
201 return CallGenerator::for_warm_call(ci, cold_cg, cg);
202 }
203 }
204 }
205
206 // Try using the type profile.
207 if (call_does_dispatch && site_count > 0 && UseTypeProfile) {
208 // The major receiver's count >= TypeProfileMajorReceiverPercent of site_count.
209 bool have_major_receiver = profile.has_receiver(0) && (100.*profile.receiver_prob(0) >= (float)TypeProfileMajorReceiverPercent);
210 ciMethod* receiver_method = NULL;
211
212 int morphism = profile.morphism();
213 if (speculative_receiver_type != NULL) {
214 if (!too_many_traps_or_recompiles(caller, bci, Deoptimization::Reason_speculate_class_check)) {
215 // We have a speculative type, we should be able to resolve
216 // the call. We do that before looking at the profiling at
217 // this invoke because it may lead to bimorphic inlining which
218 // a speculative type should help us avoid.
219 receiver_method = callee->resolve_invoke(jvms->method()->holder(),
220 speculative_receiver_type);
221 if (receiver_method == NULL) {
222 speculative_receiver_type = NULL;
223 } else {
224 morphism = 1;
225 }
226 } else {
227 // speculation failed before. Use profiling at the call
228 // (could allow bimorphic inlining for instance).
229 speculative_receiver_type = NULL;
230 }
231 }
232 if (receiver_method == NULL &&
233 (have_major_receiver || morphism == 1 ||
234 (morphism == 2 && UseBimorphicInlining))) {
235 // receiver_method = profile.method();
236 // Profiles do not suggest methods now. Look it up in the major receiver.
237 receiver_method = callee->resolve_invoke(jvms->method()->holder(),
238 profile.receiver(0));
239 }
240 if (receiver_method != NULL) {
241 // The single majority receiver sufficiently outweighs the minority.
242 CallGenerator* hit_cg = this->call_generator(receiver_method,
243 vtable_index, !call_does_dispatch, jvms, allow_inline, prof_factor);
244 if (hit_cg != NULL) {
245 // Look up second receiver.
246 CallGenerator* next_hit_cg = NULL;
247 ciMethod* next_receiver_method = NULL;
248 if (morphism == 2 && UseBimorphicInlining) {
249 next_receiver_method = callee->resolve_invoke(jvms->method()->holder(),
250 profile.receiver(1));
251 if (next_receiver_method != NULL) {
252 next_hit_cg = this->call_generator(next_receiver_method,
253 vtable_index, !call_does_dispatch, jvms,
254 allow_inline, prof_factor);
255 if (next_hit_cg != NULL && !next_hit_cg->is_inline() &&
256 have_major_receiver && UseOnlyInlinedBimorphic) {
257 // Skip if we can't inline second receiver's method
258 next_hit_cg = NULL;
259 }
260 }
261 }
262 CallGenerator* miss_cg;
263 Deoptimization::DeoptReason reason = (morphism == 2
264 ? Deoptimization::Reason_bimorphic
265 : Deoptimization::reason_class_check(speculative_receiver_type != NULL));
266 if ((morphism == 1 || (morphism == 2 && next_hit_cg != NULL)) &&
267 !too_many_traps_or_recompiles(caller, bci, reason)
268 ) {
269 // Generate uncommon trap for class check failure path
270 // in case of monomorphic or bimorphic virtual call site.
271 miss_cg = CallGenerator::for_uncommon_trap(callee, reason,
272 Deoptimization::Action_maybe_recompile);
273 } else {
274 // Generate virtual call for class check failure path
275 // in case of polymorphic virtual call site.
276 miss_cg = CallGenerator::for_virtual_call(callee, vtable_index);
277 }
278 if (miss_cg != NULL) {
279 if (next_hit_cg != NULL) {
280 assert(speculative_receiver_type == NULL, "shouldn't end up here if we used speculation");
281 trace_type_profile(C, jvms->method(), jvms->depth() - 1, jvms->bci(), next_receiver_method, profile.receiver(1), site_count, profile.receiver_count(1));
282 // We don't need to record dependency on a receiver here and below.
283 // Whenever we inline, the dependency is added by Parse::Parse().
284 miss_cg = CallGenerator::for_predicted_call(profile.receiver(1), miss_cg, next_hit_cg, PROB_MAX);
285 }
286 if (miss_cg != NULL) {
287 ciKlass* k = speculative_receiver_type != NULL ? speculative_receiver_type : profile.receiver(0);
288 trace_type_profile(C, jvms->method(), jvms->depth() - 1, jvms->bci(), receiver_method, k, site_count, receiver_count);
289 float hit_prob = speculative_receiver_type != NULL ? 1.0 : profile.receiver_prob(0);
290 CallGenerator* cg = CallGenerator::for_predicted_call(k, miss_cg, hit_cg, hit_prob);
291 if (cg != NULL) return cg;
292 }
293 }
294 }
295 }
296 }
297
298 // If there is only one implementor of this interface then we
299 // may be able to bind this invoke directly to the implementing
300 // klass but we need both a dependence on the single interface
301 // and on the method we bind to. Additionally since all we know
302 // about the receiver type is that it's supposed to implement the
303 // interface we have to insert a check that it's the class we
304 // expect. Interface types are not checked by the verifier so
305 // they are roughly equivalent to Object.
306 // The number of implementors for declared_interface is less or
307 // equal to the number of implementors for target->holder() so
308 // if number of implementors of target->holder() == 1 then
309 // number of implementors for decl_interface is 0 or 1. If
310 // it's 0 then no class implements decl_interface and there's
311 // no point in inlining.
312 if (call_does_dispatch && bytecode == Bytecodes::_invokeinterface) {
313 ciInstanceKlass* declared_interface =
314 caller->get_declared_method_holder_at_bci(bci)->as_instance_klass();
315 ciInstanceKlass* singleton = declared_interface->unique_implementor();
316
317 if (singleton != NULL &&
318 (!callee->is_default_method() || callee->is_overpass()) /* CHA doesn't support default methods yet */) {
319 assert(singleton != declared_interface, "not a unique implementor");
320
321 ciMethod* cha_monomorphic_target =
322 callee->find_monomorphic_target(caller->holder(), declared_interface, singleton);
323
324 if (cha_monomorphic_target != NULL &&
325 cha_monomorphic_target->holder() != env()->Object_klass()) { // subtype check against Object is useless
326 ciKlass* holder = cha_monomorphic_target->holder();
327
328 // Try to inline the method found by CHA. Inlined method is guarded by the type check.
329 CallGenerator* hit_cg = call_generator(cha_monomorphic_target,
330 vtable_index, !call_does_dispatch, jvms, allow_inline, prof_factor);
331
332 // Deoptimize on type check fail. The interpreter will throw ICCE for us.
333 CallGenerator* miss_cg = CallGenerator::for_uncommon_trap(callee,
334 Deoptimization::Reason_class_check, Deoptimization::Action_none);
335
336 CallGenerator* cg = CallGenerator::for_guarded_call(holder, miss_cg, hit_cg);
337 if (hit_cg != NULL && cg != NULL) {
338 dependencies()->assert_unique_concrete_method(declared_interface, cha_monomorphic_target);
339 return cg;
340 }
341 }
342 }
343 }
344 }
345
346 // Nothing claimed the intrinsic, we go with straight-forward inlining
347 // for already discovered intrinsic.
348 if (allow_inline && allow_intrinsics && cg_intrinsic != NULL) {
349 assert(cg_intrinsic->does_virtual_dispatch(), "sanity");
350 return cg_intrinsic;
351 }
352
353 // There was no special inlining tactic, or it bailed out.
354 // Use a more generic tactic, like a simple call.
355 if (call_does_dispatch) {
356 const char* msg = "virtual call";
357 if (PrintInlining) print_inlining(callee, jvms->depth() - 1, jvms->bci(), msg);
358 C->log_inline_failure(msg);
359 return CallGenerator::for_virtual_call(callee, vtable_index);
360 } else {
361 // Class Hierarchy Analysis or Type Profile reveals a unique target,
362 // or it is a static or special call.
363 return CallGenerator::for_direct_call(callee, should_delay_inlining(callee, jvms));
364 }
365 }
366
367 // Return true for methods that shouldn't be inlined early so that
368 // they are easier to analyze and optimize as intrinsics.
369 bool Compile::should_delay_string_inlining(ciMethod* call_method, JVMState* jvms) {
370 if (has_stringbuilder()) {
371
372 if ((call_method->holder() == C->env()->StringBuilder_klass() ||
373 call_method->holder() == C->env()->StringBuffer_klass()) &&
374 (jvms->method()->holder() == C->env()->StringBuilder_klass() ||
375 jvms->method()->holder() == C->env()->StringBuffer_klass())) {
376 // Delay SB calls only when called from non-SB code
377 return false;
378 }
379
380 switch (call_method->intrinsic_id()) {
381 case vmIntrinsics::_StringBuilder_void:
382 case vmIntrinsics::_StringBuilder_int:
383 case vmIntrinsics::_StringBuilder_String:
384 case vmIntrinsics::_StringBuilder_append_char:
385 case vmIntrinsics::_StringBuilder_append_int:
386 case vmIntrinsics::_StringBuilder_append_String:
387 case vmIntrinsics::_StringBuilder_toString:
388 case vmIntrinsics::_StringBuffer_void:
389 case vmIntrinsics::_StringBuffer_int:
390 case vmIntrinsics::_StringBuffer_String:
391 case vmIntrinsics::_StringBuffer_append_char:
392 case vmIntrinsics::_StringBuffer_append_int:
393 case vmIntrinsics::_StringBuffer_append_String:
394 case vmIntrinsics::_StringBuffer_toString:
395 case vmIntrinsics::_Integer_toString:
396 return true;
397
398 case vmIntrinsics::_String_String:
399 {
400 Node* receiver = jvms->map()->in(jvms->argoff() + 1);
401 if (receiver->is_Proj() && receiver->in(0)->is_CallStaticJava()) {
402 CallStaticJavaNode* csj = receiver->in(0)->as_CallStaticJava();
403 ciMethod* m = csj->method();
404 if (m != NULL &&
405 (m->intrinsic_id() == vmIntrinsics::_StringBuffer_toString ||
406 m->intrinsic_id() == vmIntrinsics::_StringBuilder_toString))
407 // Delay String.<init>(new SB())
408 return true;
409 }
410 return false;
411 }
412
413 default:
414 return false;
415 }
416 }
417 return false;
418 }
419
420 bool Compile::should_delay_boxing_inlining(ciMethod* call_method, JVMState* jvms) {
421 if (eliminate_boxing() && call_method->is_boxing_method()) {
422 set_has_boxed_value(true);
423 return aggressive_unboxing();
424 }
425 return false;
426 }
427
428 bool Compile::should_delay_vector_inlining(ciMethod* call_method, JVMState* jvms) {
429 return EnableVectorSupport && call_method->is_vector_method();
430 }
431
432 bool Compile::should_delay_vector_reboxing_inlining(ciMethod* call_method, JVMState* jvms) {
433 return EnableVectorSupport && (call_method->intrinsic_id() == vmIntrinsics::_VectorRebox);
434 }
435
436 // uncommon-trap call-sites where callee is unloaded, uninitialized or will not link
437 bool Parse::can_not_compile_call_site(ciMethod *dest_method, ciInstanceKlass* klass) {
438 // Additional inputs to consider...
439 // bc = bc()
440 // caller = method()
441 // iter().get_method_holder_index()
442 assert( dest_method->is_loaded(), "ciTypeFlow should not let us get here" );
443 // Interface classes can be loaded & linked and never get around to
444 // being initialized. Uncommon-trap for not-initialized static or
445 // v-calls. Let interface calls happen.
446 ciInstanceKlass* holder_klass = dest_method->holder();
447 if (!holder_klass->is_being_initialized() &&
448 !holder_klass->is_initialized() &&
449 !holder_klass->is_interface()) {
450 uncommon_trap(Deoptimization::Reason_uninitialized,
451 Deoptimization::Action_reinterpret,
452 holder_klass);
453 return true;
454 }
455
456 assert(dest_method->is_loaded(), "dest_method: typeflow responsibility");
457 return false;
458 }
459
460 #ifdef ASSERT
461 static bool check_call_consistency(JVMState* jvms, CallGenerator* cg) {
462 ciMethod* symbolic_info = jvms->method()->get_method_at_bci(jvms->bci());
463 ciMethod* resolved_method = cg->method();
464 if (!ciMethod::is_consistent_info(symbolic_info, resolved_method)) {
465 tty->print_cr("JVMS:");
466 jvms->dump();
467 tty->print_cr("Bytecode info:");
468 jvms->method()->get_method_at_bci(jvms->bci())->print(); tty->cr();
469 tty->print_cr("Resolved method:");
470 cg->method()->print(); tty->cr();
471 return false;
472 }
473 return true;
474 }
475 #endif // ASSERT
476
477 //------------------------------do_call----------------------------------------
478 // Handle your basic call. Inline if we can & want to, else just setup call.
479 void Parse::do_call() {
480 // It's likely we are going to add debug info soon.
481 // Also, if we inline a guy who eventually needs debug info for this JVMS,
482 // our contribution to it is cleaned up right here.
483 kill_dead_locals();
484
485 C->print_inlining_assert_ready();
486
487 // Set frequently used booleans
488 const bool is_virtual = bc() == Bytecodes::_invokevirtual;
489 const bool is_virtual_or_interface = is_virtual || bc() == Bytecodes::_invokeinterface;
490 const bool has_receiver = Bytecodes::has_receiver(bc());
491
492 // Find target being called
493 bool will_link;
494 ciSignature* declared_signature = NULL;
495 ciMethod* orig_callee = iter().get_method(will_link, &declared_signature); // callee in the bytecode
496 ciInstanceKlass* holder_klass = orig_callee->holder();
497 ciKlass* holder = iter().get_declared_method_holder();
498 ciInstanceKlass* klass = ciEnv::get_instance_klass_for_declared_method_holder(holder);
499 assert(declared_signature != NULL, "cannot be null");
500
501 // Bump max node limit for JSR292 users
502 if (bc() == Bytecodes::_invokedynamic || orig_callee->is_method_handle_intrinsic()) {
503 C->set_max_node_limit(3*MaxNodeLimit);
504 }
505
506 // uncommon-trap when callee is unloaded, uninitialized or will not link
507 // bailout when too many arguments for register representation
508 if (!will_link || can_not_compile_call_site(orig_callee, klass)) {
509 if (PrintOpto && (Verbose || WizardMode)) {
510 method()->print_name(); tty->print_cr(" can not compile call at bci %d to:", bci());
511 orig_callee->print_name(); tty->cr();
512 }
513 return;
514 }
515 assert(holder_klass->is_loaded(), "");
516 //assert((bc_callee->is_static() || is_invokedynamic) == !has_receiver , "must match bc"); // XXX invokehandle (cur_bc_raw)
517 // Note: this takes into account invokeinterface of methods declared in java/lang/Object,
518 // which should be invokevirtuals but according to the VM spec may be invokeinterfaces
519 assert(holder_klass->is_interface() || holder_klass->super() == NULL || (bc() != Bytecodes::_invokeinterface), "must match bc");
520 // Note: In the absence of miranda methods, an abstract class K can perform
521 // an invokevirtual directly on an interface method I.m if K implements I.
522
523 // orig_callee is the resolved callee which's signature includes the
524 // appendix argument.
525 const int nargs = orig_callee->arg_size();
526 const bool is_signature_polymorphic = MethodHandles::is_signature_polymorphic(orig_callee->intrinsic_id());
527
528 // Push appendix argument (MethodType, CallSite, etc.), if one.
529 if (iter().has_appendix()) {
530 ciObject* appendix_arg = iter().get_appendix();
531 const TypeOopPtr* appendix_arg_type = TypeOopPtr::make_from_constant(appendix_arg, /* require_const= */ true);
532 Node* appendix_arg_node = _gvn.makecon(appendix_arg_type);
533 push(appendix_arg_node);
534 }
535
536 // ---------------------
537 // Does Class Hierarchy Analysis reveal only a single target of a v-call?
538 // Then we may inline or make a static call, but become dependent on there being only 1 target.
539 // Does the call-site type profile reveal only one receiver?
540 // Then we may introduce a run-time check and inline on the path where it succeeds.
541 // The other path may uncommon_trap, check for another receiver, or do a v-call.
542
543 // Try to get the most accurate receiver type
544 ciMethod* callee = orig_callee;
545 int vtable_index = Method::invalid_vtable_index;
546 bool call_does_dispatch = false;
547
548 // Speculative type of the receiver if any
549 ciKlass* speculative_receiver_type = NULL;
550 if (is_virtual_or_interface) {
551 Node* receiver_node = stack(sp() - nargs);
552 const TypeOopPtr* receiver_type = _gvn.type(receiver_node)->isa_oopptr();
553 // call_does_dispatch and vtable_index are out-parameters. They might be changed.
554 // For arrays, klass below is Object. When vtable calls are used,
555 // resolving the call with Object would allow an illegal call to
556 // finalize() on an array. We use holder instead: illegal calls to
557 // finalize() won't be compiled as vtable calls (IC call
558 // resolution will catch the illegal call) and the few legal calls
559 // on array types won't be either.
560 callee = C->optimize_virtual_call(method(), bci(), klass, holder, orig_callee,
561 receiver_type, is_virtual,
562 call_does_dispatch, vtable_index); // out-parameters
563 speculative_receiver_type = receiver_type != NULL ? receiver_type->speculative_type() : NULL;
564 }
565
566 // Additional receiver subtype checks for interface calls via invokespecial or invokeinterface.
567 ciKlass* receiver_constraint = NULL;
568 if (iter().cur_bc_raw() == Bytecodes::_invokespecial && !orig_callee->is_object_initializer()) {
569 ciInstanceKlass* calling_klass = method()->holder();
570 ciInstanceKlass* sender_klass =
571 calling_klass->is_unsafe_anonymous() ? calling_klass->unsafe_anonymous_host() :
572 calling_klass;
573 if (sender_klass->is_interface()) {
574 receiver_constraint = sender_klass;
575 }
576 } else if (iter().cur_bc_raw() == Bytecodes::_invokeinterface && orig_callee->is_private()) {
577 assert(holder->is_interface(), "How did we get a non-interface method here!");
578 receiver_constraint = holder;
579 }
580
581 if (receiver_constraint != NULL) {
582 Node* receiver_node = stack(sp() - nargs);
583 Node* cls_node = makecon(TypeKlassPtr::make(receiver_constraint));
584 Node* bad_type_ctrl = NULL;
585 Node* casted_receiver = gen_checkcast(receiver_node, cls_node, &bad_type_ctrl);
586 if (bad_type_ctrl != NULL) {
587 PreserveJVMState pjvms(this);
588 set_control(bad_type_ctrl);
589 uncommon_trap(Deoptimization::Reason_class_check,
590 Deoptimization::Action_none);
591 }
592 if (stopped()) {
593 return; // MUST uncommon-trap?
594 }
595 set_stack(sp() - nargs, casted_receiver);
596 }
597
598 // Note: It's OK to try to inline a virtual call.
599 // The call generator will not attempt to inline a polymorphic call
600 // unless it knows how to optimize the receiver dispatch.
601 bool try_inline = (C->do_inlining() || InlineAccessors);
602
603 // ---------------------
604 dec_sp(nargs); // Temporarily pop args for JVM state of call
605 JVMState* jvms = sync_jvms();
606
607 // ---------------------
608 // Decide call tactic.
609 // This call checks with CHA, the interpreter profile, intrinsics table, etc.
610 // It decides whether inlining is desirable or not.
611 CallGenerator* cg = C->call_generator(callee, vtable_index, call_does_dispatch, jvms, try_inline, prof_factor(), speculative_receiver_type);
612
613 // NOTE: Don't use orig_callee and callee after this point! Use cg->method() instead.
614 orig_callee = callee = NULL;
615
616 // ---------------------
617 // Round double arguments before call
618 round_double_arguments(cg->method());
619
620 // Feed profiling data for arguments to the type system so it can
621 // propagate it as speculative types
622 record_profiled_arguments_for_speculation(cg->method(), bc());
623
624 #ifndef PRODUCT
625 // bump global counters for calls
626 count_compiled_calls(/*at_method_entry*/ false, cg->is_inline());
627
628 // Record first part of parsing work for this call
629 parse_histogram()->record_change();
630 #endif // not PRODUCT
631
632 assert(jvms == this->jvms(), "still operating on the right JVMS");
633 assert(jvms_in_sync(), "jvms must carry full info into CG");
634
635 // save across call, for a subsequent cast_not_null.
636 Node* receiver = has_receiver ? argument(0) : NULL;
637
638 // The extra CheckCastPPs for speculative types mess with PhaseStringOpts
639 if (receiver != NULL && !call_does_dispatch && !cg->is_string_late_inline()) {
640 // Feed profiling data for a single receiver to the type system so
641 // it can propagate it as a speculative type
642 receiver = record_profiled_receiver_for_speculation(receiver);
643 }
644
645 // Bump method data counters (We profile *before* the call is made
646 // because exceptions don't return to the call site.)
647 profile_call(receiver);
648
649 JVMState* new_jvms = cg->generate(jvms);
650 if (new_jvms == NULL) {
651 // When inlining attempt fails (e.g., too many arguments),
652 // it may contaminate the current compile state, making it
653 // impossible to pull back and try again. Once we call
654 // cg->generate(), we are committed. If it fails, the whole
655 // compilation task is compromised.
656 if (failing()) return;
657
658 // This can happen if a library intrinsic is available, but refuses
659 // the call site, perhaps because it did not match a pattern the
660 // intrinsic was expecting to optimize. Should always be possible to
661 // get a normal java call that may inline in that case
662 cg = C->call_generator(cg->method(), vtable_index, call_does_dispatch, jvms, try_inline, prof_factor(), speculative_receiver_type, /* allow_intrinsics= */ false);
663 new_jvms = cg->generate(jvms);
664 if (new_jvms == NULL) {
665 guarantee(failing(), "call failed to generate: calls should work");
666 return;
667 }
668 }
669
670 if (cg->is_inline()) {
671 // Accumulate has_loops estimate
672 C->set_has_loops(C->has_loops() || cg->method()->has_loops());
673 C->env()->notice_inlined_method(cg->method());
674 }
675
676 // Reset parser state from [new_]jvms, which now carries results of the call.
677 // Return value (if any) is already pushed on the stack by the cg.
678 add_exception_states_from(new_jvms);
679 if (new_jvms->map()->control() == top()) {
680 stop_and_kill_map();
681 } else {
682 assert(new_jvms->same_calls_as(jvms), "method/bci left unchanged");
683 set_jvms(new_jvms);
684 }
685
686 assert(check_call_consistency(jvms, cg), "inconsistent info");
687
688 if (!stopped()) {
689 // This was some sort of virtual call, which did a null check for us.
690 // Now we can assert receiver-not-null, on the normal return path.
691 if (receiver != NULL && cg->is_virtual()) {
692 Node* cast = cast_not_null(receiver);
693 // %%% assert(receiver == cast, "should already have cast the receiver");
694 }
695
696 // Round double result after a call from strict to non-strict code
697 round_double_result(cg->method());
698
699 ciType* rtype = cg->method()->return_type();
700 ciType* ctype = declared_signature->return_type();
701
702 if (Bytecodes::has_optional_appendix(iter().cur_bc_raw()) || is_signature_polymorphic) {
703 // Be careful here with return types.
704 if (ctype != rtype) {
705 BasicType rt = rtype->basic_type();
706 BasicType ct = ctype->basic_type();
707 if (ct == T_VOID) {
708 // It's OK for a method to return a value that is discarded.
709 // The discarding does not require any special action from the caller.
710 // The Java code knows this, at VerifyType.isNullConversion.
711 pop_node(rt); // whatever it was, pop it
712 } else if (rt == T_INT || is_subword_type(rt)) {
713 // Nothing. These cases are handled in lambda form bytecode.
714 assert(ct == T_INT || is_subword_type(ct), "must match: rt=%s, ct=%s", type2name(rt), type2name(ct));
715 } else if (is_reference_type(rt)) {
716 assert(is_reference_type(ct), "rt=%s, ct=%s", type2name(rt), type2name(ct));
717 if (ctype->is_loaded()) {
718 const TypeOopPtr* arg_type = TypeOopPtr::make_from_klass(rtype->as_klass());
719 const Type* sig_type = TypeOopPtr::make_from_klass(ctype->as_klass());
720 if (arg_type != NULL && !arg_type->higher_equal(sig_type)) {
721 Node* retnode = pop();
722 Node* cast_obj = _gvn.transform(new CheckCastPPNode(control(), retnode, sig_type));
723 push(cast_obj);
724 }
725 }
726 } else {
727 assert(rt == ct, "unexpected mismatch: rt=%s, ct=%s", type2name(rt), type2name(ct));
728 // push a zero; it's better than getting an oop/int mismatch
729 pop_node(rt);
730 Node* retnode = zerocon(ct);
731 push_node(ct, retnode);
732 }
733 // Now that the value is well-behaved, continue with the call-site type.
734 rtype = ctype;
735 }
736 } else {
737 // Symbolic resolution enforces the types to be the same.
738 // NOTE: We must relax the assert for unloaded types because two
739 // different ciType instances of the same unloaded class type
740 // can appear to be "loaded" by different loaders (depending on
741 // the accessing class).
742 assert(!rtype->is_loaded() || !ctype->is_loaded() || rtype == ctype,
743 "mismatched return types: rtype=%s, ctype=%s", rtype->name(), ctype->name());
744 }
745
746 // If the return type of the method is not loaded, assert that the
747 // value we got is a null. Otherwise, we need to recompile.
748 if (!rtype->is_loaded()) {
749 if (PrintOpto && (Verbose || WizardMode)) {
750 method()->print_name(); tty->print_cr(" asserting nullness of result at bci: %d", bci());
751 cg->method()->print_name(); tty->cr();
752 }
753 if (C->log() != NULL) {
754 C->log()->elem("assert_null reason='return' klass='%d'",
755 C->log()->identify(rtype));
756 }
757 // If there is going to be a trap, put it at the next bytecode:
758 set_bci(iter().next_bci());
759 null_assert(peek());
760 set_bci(iter().cur_bci()); // put it back
761 }
762 BasicType ct = ctype->basic_type();
763 if (is_reference_type(ct)) {
764 record_profiled_return_for_speculation();
765 }
766 }
767
768 // Restart record of parsing work after possible inlining of call
769 #ifndef PRODUCT
770 parse_histogram()->set_initial_state(bc());
771 #endif
772 }
773
774 //---------------------------catch_call_exceptions-----------------------------
775 // Put a Catch and CatchProj nodes behind a just-created call.
776 // Send their caught exceptions to the proper handler.
777 // This may be used after a call to the rethrow VM stub,
778 // when it is needed to process unloaded exception classes.
779 void Parse::catch_call_exceptions(ciExceptionHandlerStream& handlers) {
780 // Exceptions are delivered through this channel:
781 Node* i_o = this->i_o();
782
783 // Add a CatchNode.
784 GrowableArray<int>* bcis = new (C->node_arena()) GrowableArray<int>(C->node_arena(), 8, 0, -1);
785 GrowableArray<const Type*>* extypes = new (C->node_arena()) GrowableArray<const Type*>(C->node_arena(), 8, 0, NULL);
786 GrowableArray<int>* saw_unloaded = new (C->node_arena()) GrowableArray<int>(C->node_arena(), 8, 0, 0);
787
788 bool default_handler = false;
789 for (; !handlers.is_done(); handlers.next()) {
790 ciExceptionHandler* h = handlers.handler();
791 int h_bci = h->handler_bci();
792 ciInstanceKlass* h_klass = h->is_catch_all() ? env()->Throwable_klass() : h->catch_klass();
793 // Do not introduce unloaded exception types into the graph:
794 if (!h_klass->is_loaded()) {
795 if (saw_unloaded->contains(h_bci)) {
796 /* We've already seen an unloaded exception with h_bci,
797 so don't duplicate. Duplication will cause the CatchNode to be
798 unnecessarily large. See 4713716. */
799 continue;
800 } else {
801 saw_unloaded->append(h_bci);
802 }
803 }
804 const Type* h_extype = TypeOopPtr::make_from_klass(h_klass);
805 // (We use make_from_klass because it respects UseUniqueSubclasses.)
806 h_extype = h_extype->join(TypeInstPtr::NOTNULL);
807 assert(!h_extype->empty(), "sanity");
808 // Note: It's OK if the BCIs repeat themselves.
809 bcis->append(h_bci);
810 extypes->append(h_extype);
811 if (h_bci == -1) {
812 default_handler = true;
813 }
814 }
815
816 if (!default_handler) {
817 bcis->append(-1);
818 extypes->append(TypeOopPtr::make_from_klass(env()->Throwable_klass())->is_instptr());
819 }
820
821 int len = bcis->length();
822 CatchNode *cn = new CatchNode(control(), i_o, len+1);
823 Node *catch_ = _gvn.transform(cn);
824
825 // now branch with the exception state to each of the (potential)
826 // handlers
827 for(int i=0; i < len; i++) {
828 // Setup JVM state to enter the handler.
829 PreserveJVMState pjvms(this);
830 // Locals are just copied from before the call.
831 // Get control from the CatchNode.
832 int handler_bci = bcis->at(i);
833 Node* ctrl = _gvn.transform( new CatchProjNode(catch_, i+1,handler_bci));
834 // This handler cannot happen?
835 if (ctrl == top()) continue;
836 set_control(ctrl);
837
838 // Create exception oop
839 const TypeInstPtr* extype = extypes->at(i)->is_instptr();
840 Node *ex_oop = _gvn.transform(new CreateExNode(extypes->at(i), ctrl, i_o));
841
842 // Handle unloaded exception classes.
843 if (saw_unloaded->contains(handler_bci)) {
844 // An unloaded exception type is coming here. Do an uncommon trap.
845 #ifndef PRODUCT
846 // We do not expect the same handler bci to take both cold unloaded
847 // and hot loaded exceptions. But, watch for it.
848 if ((Verbose || WizardMode) && extype->is_loaded()) {
849 tty->print("Warning: Handler @%d takes mixed loaded/unloaded exceptions in ", bci());
850 method()->print_name(); tty->cr();
851 } else if (PrintOpto && (Verbose || WizardMode)) {
852 tty->print("Bailing out on unloaded exception type ");
853 extype->klass()->print_name();
854 tty->print(" at bci:%d in ", bci());
855 method()->print_name(); tty->cr();
856 }
857 #endif
858 // Emit an uncommon trap instead of processing the block.
859 set_bci(handler_bci);
860 push_ex_oop(ex_oop);
861 uncommon_trap(Deoptimization::Reason_unloaded,
862 Deoptimization::Action_reinterpret,
863 extype->klass(), "!loaded exception");
864 set_bci(iter().cur_bci()); // put it back
865 continue;
866 }
867
868 // go to the exception handler
869 if (handler_bci < 0) { // merge with corresponding rethrow node
870 throw_to_exit(make_exception_state(ex_oop));
871 } else { // Else jump to corresponding handle
872 push_ex_oop(ex_oop); // Clear stack and push just the oop.
873 merge_exception(handler_bci);
874 }
875 }
876
877 // The first CatchProj is for the normal return.
878 // (Note: If this is a call to rethrow_Java, this node goes dead.)
879 set_control(_gvn.transform( new CatchProjNode(catch_, CatchProjNode::fall_through_index, CatchProjNode::no_handler_bci)));
880 }
881
882
883 //----------------------------catch_inline_exceptions--------------------------
884 // Handle all exceptions thrown by an inlined method or individual bytecode.
885 // Common case 1: we have no handler, so all exceptions merge right into
886 // the rethrow case.
887 // Case 2: we have some handlers, with loaded exception klasses that have
888 // no subklasses. We do a Deutsch-Shiffman style type-check on the incoming
889 // exception oop and branch to the handler directly.
890 // Case 3: We have some handlers with subklasses or are not loaded at
891 // compile-time. We have to call the runtime to resolve the exception.
892 // So we insert a RethrowCall and all the logic that goes with it.
893 void Parse::catch_inline_exceptions(SafePointNode* ex_map) {
894 // Caller is responsible for saving away the map for normal control flow!
895 assert(stopped(), "call set_map(NULL) first");
896 assert(method()->has_exception_handlers(), "don't come here w/o work to do");
897
898 Node* ex_node = saved_ex_oop(ex_map);
899 if (ex_node == top()) {
900 // No action needed.
901 return;
902 }
903 const TypeInstPtr* ex_type = _gvn.type(ex_node)->isa_instptr();
904 NOT_PRODUCT(if (ex_type==NULL) tty->print_cr("*** Exception not InstPtr"));
905 if (ex_type == NULL)
906 ex_type = TypeOopPtr::make_from_klass(env()->Throwable_klass())->is_instptr();
907
908 // determine potential exception handlers
909 ciExceptionHandlerStream handlers(method(), bci(),
910 ex_type->klass()->as_instance_klass(),
911 ex_type->klass_is_exact());
912
913 // Start executing from the given throw state. (Keep its stack, for now.)
914 // Get the exception oop as known at compile time.
915 ex_node = use_exception_state(ex_map);
916
917 // Get the exception oop klass from its header
918 Node* ex_klass_node = NULL;
919 if (has_ex_handler() && !ex_type->klass_is_exact()) {
920 Node* p = basic_plus_adr( ex_node, ex_node, oopDesc::klass_offset_in_bytes());
921 ex_klass_node = _gvn.transform(LoadKlassNode::make(_gvn, NULL, immutable_memory(), p, TypeInstPtr::KLASS, TypeKlassPtr::OBJECT));
922
923 // Compute the exception klass a little more cleverly.
924 // Obvious solution is to simple do a LoadKlass from the 'ex_node'.
925 // However, if the ex_node is a PhiNode, I'm going to do a LoadKlass for
926 // each arm of the Phi. If I know something clever about the exceptions
927 // I'm loading the class from, I can replace the LoadKlass with the
928 // klass constant for the exception oop.
929 if (ex_node->is_Phi()) {
930 ex_klass_node = new PhiNode(ex_node->in(0), TypeKlassPtr::OBJECT);
931 for (uint i = 1; i < ex_node->req(); i++) {
932 Node* ex_in = ex_node->in(i);
933 if (ex_in == top() || ex_in == NULL) {
934 // This path was not taken.
935 ex_klass_node->init_req(i, top());
936 continue;
937 }
938 Node* p = basic_plus_adr(ex_in, ex_in, oopDesc::klass_offset_in_bytes());
939 Node* k = _gvn.transform( LoadKlassNode::make(_gvn, NULL, immutable_memory(), p, TypeInstPtr::KLASS, TypeKlassPtr::OBJECT));
940 ex_klass_node->init_req( i, k );
941 }
942 _gvn.set_type(ex_klass_node, TypeKlassPtr::OBJECT);
943
944 }
945 }
946
947 // Scan the exception table for applicable handlers.
948 // If none, we can call rethrow() and be done!
949 // If precise (loaded with no subklasses), insert a D.S. style
950 // pointer compare to the correct handler and loop back.
951 // If imprecise, switch to the Rethrow VM-call style handling.
952
953 int remaining = handlers.count_remaining();
954
955 // iterate through all entries sequentially
956 for (;!handlers.is_done(); handlers.next()) {
957 ciExceptionHandler* handler = handlers.handler();
958
959 if (handler->is_rethrow()) {
960 // If we fell off the end of the table without finding an imprecise
961 // exception klass (and without finding a generic handler) then we
962 // know this exception is not handled in this method. We just rethrow
963 // the exception into the caller.
964 throw_to_exit(make_exception_state(ex_node));
965 return;
966 }
967
968 // exception handler bci range covers throw_bci => investigate further
969 int handler_bci = handler->handler_bci();
970
971 if (remaining == 1) {
972 push_ex_oop(ex_node); // Push exception oop for handler
973 if (PrintOpto && WizardMode) {
974 tty->print_cr(" Catching every inline exception bci:%d -> handler_bci:%d", bci(), handler_bci);
975 }
976 merge_exception(handler_bci); // jump to handler
977 return; // No more handling to be done here!
978 }
979
980 // Get the handler's klass
981 ciInstanceKlass* klass = handler->catch_klass();
982
983 if (!klass->is_loaded()) { // klass is not loaded?
984 // fall through into catch_call_exceptions which will emit a
985 // handler with an uncommon trap.
986 break;
987 }
988
989 if (klass->is_interface()) // should not happen, but...
990 break; // bail out
991
992 // Check the type of the exception against the catch type
993 const TypeKlassPtr *tk = TypeKlassPtr::make(klass);
994 Node* con = _gvn.makecon(tk);
995 Node* not_subtype_ctrl = gen_subtype_check(ex_klass_node, con);
996 if (!stopped()) {
997 PreserveJVMState pjvms(this);
998 const TypeInstPtr* tinst = TypeOopPtr::make_from_klass_unique(klass)->cast_to_ptr_type(TypePtr::NotNull)->is_instptr();
999 assert(klass->has_subklass() || tinst->klass_is_exact(), "lost exactness");
1000 Node* ex_oop = _gvn.transform(new CheckCastPPNode(control(), ex_node, tinst));
1001 push_ex_oop(ex_oop); // Push exception oop for handler
1002 if (PrintOpto && WizardMode) {
1003 tty->print(" Catching inline exception bci:%d -> handler_bci:%d -- ", bci(), handler_bci);
1004 klass->print_name();
1005 tty->cr();
1006 }
1007 merge_exception(handler_bci);
1008 }
1009 set_control(not_subtype_ctrl);
1010
1011 // Come here if exception does not match handler.
1012 // Carry on with more handler checks.
1013 --remaining;
1014 }
1015
1016 assert(!stopped(), "you should return if you finish the chain");
1017
1018 // Oops, need to call into the VM to resolve the klasses at runtime.
1019 // Note: This call must not deoptimize, since it is not a real at this bci!
1020 kill_dead_locals();
1021
1022 make_runtime_call(RC_NO_LEAF | RC_MUST_THROW,
1023 OptoRuntime::rethrow_Type(),
1024 OptoRuntime::rethrow_stub(),
1025 NULL, NULL,
1026 ex_node);
1027
1028 // Rethrow is a pure call, no side effects, only a result.
1029 // The result cannot be allocated, so we use I_O
1030
1031 // Catch exceptions from the rethrow
1032 catch_call_exceptions(handlers);
1033 }
1034
1035
1036 // (Note: Moved add_debug_info into GraphKit::add_safepoint_edges.)
1037
1038
1039 #ifndef PRODUCT
1040 void Parse::count_compiled_calls(bool at_method_entry, bool is_inline) {
1041 if( CountCompiledCalls ) {
1042 if( at_method_entry ) {
1043 // bump invocation counter if top method (for statistics)
1044 if (CountCompiledCalls && depth() == 1) {
1045 const TypePtr* addr_type = TypeMetadataPtr::make(method());
1046 Node* adr1 = makecon(addr_type);
1047 Node* adr2 = basic_plus_adr(adr1, adr1, in_bytes(Method::compiled_invocation_counter_offset()));
1048 increment_counter(adr2);
1049 }
1050 } else if (is_inline) {
1051 switch (bc()) {
1052 case Bytecodes::_invokevirtual: increment_counter(SharedRuntime::nof_inlined_calls_addr()); break;
1053 case Bytecodes::_invokeinterface: increment_counter(SharedRuntime::nof_inlined_interface_calls_addr()); break;
1054 case Bytecodes::_invokestatic:
1055 case Bytecodes::_invokedynamic:
1056 case Bytecodes::_invokespecial: increment_counter(SharedRuntime::nof_inlined_static_calls_addr()); break;
1057 default: fatal("unexpected call bytecode");
1058 }
1059 } else {
1060 switch (bc()) {
1061 case Bytecodes::_invokevirtual: increment_counter(SharedRuntime::nof_normal_calls_addr()); break;
1062 case Bytecodes::_invokeinterface: increment_counter(SharedRuntime::nof_interface_calls_addr()); break;
1063 case Bytecodes::_invokestatic:
1064 case Bytecodes::_invokedynamic:
1065 case Bytecodes::_invokespecial: increment_counter(SharedRuntime::nof_static_calls_addr()); break;
1066 default: fatal("unexpected call bytecode");
1067 }
1068 }
1069 }
1070 }
1071 #endif //PRODUCT
1072
1073
1074 ciMethod* Compile::optimize_virtual_call(ciMethod* caller, int bci, ciInstanceKlass* klass,
1075 ciKlass* holder, ciMethod* callee,
1076 const TypeOopPtr* receiver_type, bool is_virtual,
1077 bool& call_does_dispatch, int& vtable_index,
1078 bool check_access) {
1079 // Set default values for out-parameters.
1080 call_does_dispatch = true;
1081 vtable_index = Method::invalid_vtable_index;
1082
1083 // Choose call strategy.
1084 ciMethod* optimized_virtual_method = optimize_inlining(caller, bci, klass, callee,
1085 receiver_type, check_access);
1086
1087 // Have the call been sufficiently improved such that it is no longer a virtual?
1088 if (optimized_virtual_method != NULL) {
1089 callee = optimized_virtual_method;
1090 call_does_dispatch = false;
1091 } else if (!UseInlineCaches && is_virtual && callee->is_loaded()) {
1092 // We can make a vtable call at this site
1093 vtable_index = callee->resolve_vtable_index(caller->holder(), holder);
1094 }
1095 return callee;
1096 }
1097
1098 // Identify possible target method and inlining style
1099 ciMethod* Compile::optimize_inlining(ciMethod* caller, int bci, ciInstanceKlass* klass,
1100 ciMethod* callee, const TypeOopPtr* receiver_type,
1101 bool check_access) {
1102 // only use for virtual or interface calls
1103
1104 // If it is obviously final, do not bother to call find_monomorphic_target,
1105 // because the class hierarchy checks are not needed, and may fail due to
1106 // incompletely loaded classes. Since we do our own class loading checks
1107 // in this module, we may confidently bind to any method.
1108 if (callee->can_be_statically_bound()) {
1109 return callee;
1110 }
1111
1112 // Attempt to improve the receiver
1113 bool actual_receiver_is_exact = false;
1114 ciInstanceKlass* actual_receiver = klass;
1115 if (receiver_type != NULL) {
1116 // Array methods are all inherited from Object, and are monomorphic.
1117 // finalize() call on array is not allowed.
1118 if (receiver_type->isa_aryptr() &&
1119 callee->holder() == env()->Object_klass() &&
1120 callee->name() != ciSymbol::finalize_method_name()) {
1121 return callee;
1122 }
1123
1124 // All other interesting cases are instance klasses.
1125 if (!receiver_type->isa_instptr()) {
1126 return NULL;
1127 }
1128
1129 ciInstanceKlass *ikl = receiver_type->klass()->as_instance_klass();
1130 if (ikl->is_loaded() && ikl->is_initialized() && !ikl->is_interface() &&
1131 (ikl == actual_receiver || ikl->is_subtype_of(actual_receiver))) {
1132 // ikl is a same or better type than the original actual_receiver,
1133 // e.g. static receiver from bytecodes.
1134 actual_receiver = ikl;
1135 // Is the actual_receiver exact?
1136 actual_receiver_is_exact = receiver_type->klass_is_exact();
1137 }
1138 }
1139
1140 ciInstanceKlass* calling_klass = caller->holder();
1141 ciMethod* cha_monomorphic_target = callee->find_monomorphic_target(calling_klass, klass, actual_receiver, check_access);
1142 if (cha_monomorphic_target != NULL) {
1143 assert(!cha_monomorphic_target->is_abstract(), "");
1144 // Look at the method-receiver type. Does it add "too much information"?
1145 ciKlass* mr_klass = cha_monomorphic_target->holder();
1146 const Type* mr_type = TypeInstPtr::make(TypePtr::BotPTR, mr_klass);
1147 if (receiver_type == NULL || !receiver_type->higher_equal(mr_type)) {
1148 // Calling this method would include an implicit cast to its holder.
1149 // %%% Not yet implemented. Would throw minor asserts at present.
1150 // %%% The most common wins are already gained by +UseUniqueSubclasses.
1151 // To fix, put the higher_equal check at the call of this routine,
1152 // and add a CheckCastPP to the receiver.
1153 if (TraceDependencies) {
1154 tty->print_cr("found unique CHA method, but could not cast up");
1155 tty->print(" method = ");
1156 cha_monomorphic_target->print();
1157 tty->cr();
1158 }
1159 if (log() != NULL) {
1160 log()->elem("missed_CHA_opportunity klass='%d' method='%d'",
1161 log()->identify(klass),
1162 log()->identify(cha_monomorphic_target));
1163 }
1164 cha_monomorphic_target = NULL;
1165 }
1166 }
1167
1168 if (cha_monomorphic_target != NULL) {
1169 // Hardwiring a virtual.
1170 assert(!callee->can_be_statically_bound(), "should have been handled earlier");
1171 assert(!cha_monomorphic_target->is_abstract(), "");
1172 if (!cha_monomorphic_target->can_be_statically_bound(actual_receiver)) {
1173 // If we inlined because CHA revealed only a single target method,
1174 // then we are dependent on that target method not getting overridden
1175 // by dynamic class loading. Be sure to test the "static" receiver
1176 // dest_method here, as opposed to the actual receiver, which may
1177 // falsely lead us to believe that the receiver is final or private.
1178 dependencies()->assert_unique_concrete_method(actual_receiver, cha_monomorphic_target);
1179 }
1180 return cha_monomorphic_target;
1181 }
1182
1183 // If the type is exact, we can still bind the method w/o a vcall.
1184 // (This case comes after CHA so we can see how much extra work it does.)
1185 if (actual_receiver_is_exact) {
1186 // In case of evolution, there is a dependence on every inlined method, since each
1187 // such method can be changed when its class is redefined.
1188 ciMethod* exact_method = callee->resolve_invoke(calling_klass, actual_receiver);
1189 if (exact_method != NULL) {
1190 if (PrintOpto) {
1191 tty->print(" Calling method via exact type @%d --- ", bci);
1192 exact_method->print_name();
1193 tty->cr();
1194 }
1195 return exact_method;
1196 }
1197 }
1198
1199 return NULL;
1200 }