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