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 
1156   if (cha_monomorphic_target != NULL) {
1157     // Hardwiring a virtual.
1158     assert(!callee->can_be_statically_bound(), "should have been handled earlier");
1159     assert(!cha_monomorphic_target->is_abstract(), "");
1160     if (!cha_monomorphic_target->can_be_statically_bound(actual_receiver)) {
1161       // If we inlined because CHA revealed only a single target method,
1162       // then we are dependent on that target method not getting overridden
1163       // by dynamic class loading.  Be sure to test the "static" receiver
1164       // dest_method here, as opposed to the actual receiver, which may
1165       // falsely lead us to believe that the receiver is final or private.
1166       dependencies()->assert_unique_concrete_method(actual_receiver, cha_monomorphic_target);
1167     }
1168     return cha_monomorphic_target;
1169   }
1170 
1171   // If the type is exact, we can still bind the method w/o a vcall.
1172   // (This case comes after CHA so we can see how much extra work it does.)
1173   if (actual_receiver_is_exact) {
1174     // In case of evolution, there is a dependence on every inlined method, since each
1175     // such method can be changed when its class is redefined.
1176     ciMethod* exact_method = callee->resolve_invoke(calling_klass, actual_receiver);
1177     if (exact_method != NULL) {
1178       if (PrintOpto) {
1179         tty->print("  Calling method via exact type @%d --- ", bci);
1180         exact_method->print_name();
1181         tty->cr();
1182       }
1183       return exact_method;
1184     }
1185   }
1186 
1187   return NULL;
1188 }