1 /*
   2  * Copyright (c) 1998, 2014, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "ci/ciCallSite.hpp"
  27 #include "ci/ciMethodHandle.hpp"
  28 #include "classfile/vmSymbols.hpp"
  29 #include "compiler/compileBroker.hpp"
  30 #include "compiler/compileLog.hpp"
  31 #include "interpreter/linkResolver.hpp"
  32 #include "opto/addnode.hpp"
  33 #include "opto/callGenerator.hpp"
  34 #include "opto/castnode.hpp"
  35 #include "opto/cfgnode.hpp"
  36 #include "opto/mulnode.hpp"
  37 #include "opto/parse.hpp"
  38 #include "opto/rootnode.hpp"
  39 #include "opto/runtime.hpp"
  40 #include "opto/subnode.hpp"
  41 #include "prims/nativeLookup.hpp"
  42 #include "runtime/sharedRuntime.hpp"
  43 
  44 void trace_type_profile(Compile* C, ciMethod *method, int depth, int bci, ciMethod *prof_method, ciKlass *prof_klass, int site_count, int receiver_count) {
  45   if (TraceTypeProfile || C->print_inlining()) {
  46     outputStream* out = tty;
  47     if (!C->print_inlining()) {
  48       if (NOT_PRODUCT(!PrintOpto &&) !PrintCompilation) {
  49         method->print_short_name();
  50         tty->cr();
  51       }
  52       CompileTask::print_inlining(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='%g'",
  98                     log->identify(callee), site_count, prof_factor);
  99     if (call_does_dispatch)  log->print(" virtual='1'");
 100     if (allow_inline)     log->print(" inline='1'");
 101     if (receiver_count >= 0) {
 102       log->print(" receiver='%d' receiver_count='%d'", rid, receiver_count);
 103       if (profile.has_receiver(1)) {
 104         log->print(" receiver2='%d' receiver2_count='%d'", r2id, profile.receiver_count(1));
 105       }
 106     }
 107     if (callee->is_method_handle_intrinsic()) {
 108       log->print(" method_handle_intrinsic='1'");
 109     }
 110     log->end_elem();
 111   }
 112 
 113   // Special case the handling of certain common, profitable library
 114   // methods.  If these methods are replaced with specialized code,
 115   // then we return it as the inlined version of the call.
 116   // We do this before the strict f.p. check below because the
 117   // intrinsics handle strict f.p. correctly.
 118   CallGenerator* cg_intrinsic = NULL;
 119   if (allow_inline && allow_intrinsics) {
 120     CallGenerator* cg = find_intrinsic(callee, call_does_dispatch);
 121     if (cg != NULL) {
 122       if (cg->is_predicated()) {
 123         // Code without intrinsic but, hopefully, inlined.
 124         CallGenerator* inline_cg = this->call_generator(callee,
 125               vtable_index, call_does_dispatch, jvms, allow_inline, prof_factor, speculative_receiver_type, false);
 126         if (inline_cg != NULL) {
 127           cg = CallGenerator::for_predicated_intrinsic(cg, inline_cg);
 128         }
 129       }
 130 
 131       // If intrinsic does the virtual dispatch, we try to use the type profile
 132       // first, and hopefully inline it as the regular virtual call below.
 133       // We will retry the intrinsic if nothing had claimed it afterwards.
 134       if (cg->does_virtual_dispatch()) {
 135         cg_intrinsic = cg;
 136         cg = NULL;
 137       } else {
 138         return cg;
 139       }
 140     }
 141   }
 142 
 143   // Do method handle calls.
 144   // NOTE: This must happen before normal inlining logic below since
 145   // MethodHandle.invoke* are native methods which obviously don't
 146   // have bytecodes and so normal inlining fails.
 147   if (callee->is_method_handle_intrinsic()) {
 148     CallGenerator* cg = CallGenerator::for_method_handle_call(jvms, caller, callee, delayed_forbidden);
 149     assert(cg == NULL || !delayed_forbidden || !cg->is_late_inline() || cg->is_mh_late_inline(), "unexpected CallGenerator");
 150     return cg;
 151   }
 152 
 153   // Do not inline strict fp into non-strict code, or the reverse
 154   if (caller->is_strict() ^ callee->is_strict()) {
 155     allow_inline = false;
 156   }
 157 
 158   // Attempt to inline...
 159   if (allow_inline) {
 160     // The profile data is only partly attributable to this caller,
 161     // scale back the call site information.
 162     float past_uses = jvms->method()->scale_count(site_count, prof_factor);
 163     // This is the number of times we expect the call code to be used.
 164     float expected_uses = past_uses;
 165 
 166     // Try inlining a bytecoded method:
 167     if (!call_does_dispatch) {
 168       InlineTree* ilt = InlineTree::find_subtree_from_root(this->ilt(), jvms->caller(), jvms->method());
 169       WarmCallInfo scratch_ci;
 170       bool should_delay = false;
 171       WarmCallInfo* ci = ilt->ok_to_inline(callee, jvms, profile, &scratch_ci, should_delay);
 172       assert(ci != &scratch_ci, "do not let this pointer escape");
 173       bool allow_inline   = (ci != NULL && !ci->is_cold());
 174       bool require_inline = (allow_inline && ci->is_hot());
 175 
 176       if (allow_inline) {
 177         CallGenerator* cg = CallGenerator::for_inline(callee, expected_uses);
 178 
 179         if (require_inline && cg != NULL) {
 180           // Delay the inlining of this method to give us the
 181           // opportunity to perform some high level optimizations
 182           // first.
 183           if (should_delay_string_inlining(callee, jvms)) {
 184             assert(!delayed_forbidden, "strange");
 185             return CallGenerator::for_string_late_inline(callee, cg);
 186           } else if (should_delay_boxing_inlining(callee, jvms)) {
 187             assert(!delayed_forbidden, "strange");
 188             return CallGenerator::for_boxing_late_inline(callee, cg);
 189           } else if ((should_delay || AlwaysIncrementalInline) && !delayed_forbidden) {
 190             return CallGenerator::for_late_inline(callee, cg);
 191           }
 192         }
 193         if (cg == NULL || should_delay) {
 194           // Fall through.
 195         } else if (require_inline || !InlineWarmCalls) {
 196           return cg;
 197         } else {
 198           CallGenerator* cold_cg = call_generator(callee, vtable_index, call_does_dispatch, jvms, false, prof_factor);
 199           return CallGenerator::for_warm_call(ci, cold_cg, cg);
 200         }
 201       }
 202     }
 203 
 204     // Try using the type profile.
 205     if (call_does_dispatch && site_count > 0 && receiver_count > 0) {
 206       // The major receiver's count >= TypeProfileMajorReceiverPercent of site_count.
 207       bool have_major_receiver = (100.*profile.receiver_prob(0) >= (float)TypeProfileMajorReceiverPercent);
 208       ciMethod* receiver_method = NULL;
 209 
 210       int morphism = profile.morphism();
 211       if (speculative_receiver_type != NULL) {
 212         // We have a speculative type, we should be able to resolve
 213         // the call. We do that before looking at the profiling at
 214         // this invoke because it may lead to bimorphic inlining which
 215         // a speculative type should help us avoid.
 216         receiver_method = callee->resolve_invoke(jvms->method()->holder(),
 217                                                  speculative_receiver_type);
 218         if (receiver_method == NULL) {
 219           speculative_receiver_type = NULL;
 220         } else {
 221           morphism = 1;
 222         }
 223       }
 224       if (receiver_method == NULL &&
 225           (have_major_receiver || morphism == 1 ||
 226            (morphism == 2 && UseBimorphicInlining))) {
 227         // receiver_method = profile.method();
 228         // Profiles do not suggest methods now.  Look it up in the major receiver.
 229         receiver_method = callee->resolve_invoke(jvms->method()->holder(),
 230                                                       profile.receiver(0));
 231       }
 232       if (receiver_method != NULL) {
 233         // The single majority receiver sufficiently outweighs the minority.
 234         CallGenerator* hit_cg = this->call_generator(receiver_method,
 235               vtable_index, !call_does_dispatch, jvms, allow_inline, prof_factor);
 236         if (hit_cg != NULL) {
 237           // Look up second receiver.
 238           CallGenerator* next_hit_cg = NULL;
 239           ciMethod* next_receiver_method = NULL;
 240           if (morphism == 2 && UseBimorphicInlining) {
 241             next_receiver_method = callee->resolve_invoke(jvms->method()->holder(),
 242                                                                profile.receiver(1));
 243             if (next_receiver_method != NULL) {
 244               next_hit_cg = this->call_generator(next_receiver_method,
 245                                   vtable_index, !call_does_dispatch, jvms,
 246                                   allow_inline, prof_factor);
 247               if (next_hit_cg != NULL && !next_hit_cg->is_inline() &&
 248                   have_major_receiver && UseOnlyInlinedBimorphic) {
 249                   // Skip if we can't inline second receiver's method
 250                   next_hit_cg = NULL;
 251               }
 252             }
 253           }
 254           CallGenerator* miss_cg;
 255           Deoptimization::DeoptReason reason = morphism == 2 ?
 256             Deoptimization::Reason_bimorphic : Deoptimization::reason_class_check(speculative_receiver_type != NULL);
 257           if ((morphism == 1 || (morphism == 2 && next_hit_cg != NULL)) &&
 258               !too_many_traps(jvms->method(), jvms->bci(), reason)
 259              ) {
 260             // Generate uncommon trap for class check failure path
 261             // in case of monomorphic or bimorphic virtual call site.
 262             miss_cg = CallGenerator::for_uncommon_trap(callee, reason,
 263                         Deoptimization::Action_maybe_recompile);
 264           } else {
 265             // Generate virtual call for class check failure path
 266             // in case of polymorphic virtual call site.
 267             miss_cg = CallGenerator::for_virtual_call(callee, vtable_index);
 268           }
 269           if (miss_cg != NULL) {
 270             if (next_hit_cg != NULL) {
 271               assert(speculative_receiver_type == NULL, "shouldn't end up here if we used speculation");
 272               trace_type_profile(C, jvms->method(), jvms->depth() - 1, jvms->bci(), next_receiver_method, profile.receiver(1), site_count, profile.receiver_count(1));
 273               // We don't need to record dependency on a receiver here and below.
 274               // Whenever we inline, the dependency is added by Parse::Parse().
 275               miss_cg = CallGenerator::for_predicted_call(profile.receiver(1), miss_cg, next_hit_cg, PROB_MAX);
 276             }
 277             if (miss_cg != NULL) {
 278               trace_type_profile(C, jvms->method(), jvms->depth() - 1, jvms->bci(), receiver_method, profile.receiver(0), site_count, receiver_count);
 279               ciKlass* k = speculative_receiver_type != NULL ? speculative_receiver_type : profile.receiver(0);
 280               float hit_prob = speculative_receiver_type != NULL ? 1.0 : profile.receiver_prob(0);
 281               CallGenerator* cg = CallGenerator::for_predicted_call(k, miss_cg, hit_cg, hit_prob);
 282               if (cg != NULL)  return cg;
 283             }
 284           }
 285         }
 286       }
 287     }
 288   }
 289 
 290   // Nothing claimed the intrinsic, we go with straight-forward inlining
 291   // for already discovered intrinsic.
 292   if (allow_inline && allow_intrinsics && cg_intrinsic != NULL) {
 293     assert(cg_intrinsic->does_virtual_dispatch(), "sanity");
 294     return cg_intrinsic;
 295   }
 296 
 297   // There was no special inlining tactic, or it bailed out.
 298   // Use a more generic tactic, like a simple call.
 299   if (call_does_dispatch) {
 300     const char* msg = "virtual call";
 301     if (PrintInlining) print_inlining(callee, jvms->depth() - 1, jvms->bci(), msg);
 302     C->log_inline_failure(msg);
 303     return CallGenerator::for_virtual_call(callee, vtable_index);
 304   } else {
 305     // Class Hierarchy Analysis or Type Profile reveals a unique target,
 306     // or it is a static or special call.
 307     return CallGenerator::for_direct_call(callee, should_delay_inlining(callee, jvms));
 308   }
 309 }
 310 
 311 // Return true for methods that shouldn't be inlined early so that
 312 // they are easier to analyze and optimize as intrinsics.
 313 bool Compile::should_delay_string_inlining(ciMethod* call_method, JVMState* jvms) {
 314   if (has_stringbuilder()) {
 315 
 316     if ((call_method->holder() == C->env()->StringBuilder_klass() ||
 317          call_method->holder() == C->env()->StringBuffer_klass()) &&
 318         (jvms->method()->holder() == C->env()->StringBuilder_klass() ||
 319          jvms->method()->holder() == C->env()->StringBuffer_klass())) {
 320       // Delay SB calls only when called from non-SB code
 321       return false;
 322     }
 323 
 324     switch (call_method->intrinsic_id()) {
 325       case vmIntrinsics::_StringBuilder_void:
 326       case vmIntrinsics::_StringBuilder_int:
 327       case vmIntrinsics::_StringBuilder_String:
 328       case vmIntrinsics::_StringBuilder_append_char:
 329       case vmIntrinsics::_StringBuilder_append_int:
 330       case vmIntrinsics::_StringBuilder_append_String:
 331       case vmIntrinsics::_StringBuilder_toString:
 332       case vmIntrinsics::_StringBuffer_void:
 333       case vmIntrinsics::_StringBuffer_int:
 334       case vmIntrinsics::_StringBuffer_String:
 335       case vmIntrinsics::_StringBuffer_append_char:
 336       case vmIntrinsics::_StringBuffer_append_int:
 337       case vmIntrinsics::_StringBuffer_append_String:
 338       case vmIntrinsics::_StringBuffer_toString:
 339       case vmIntrinsics::_Integer_toString:
 340         return true;
 341 
 342       case vmIntrinsics::_String_String:
 343         {
 344           Node* receiver = jvms->map()->in(jvms->argoff() + 1);
 345           if (receiver->is_Proj() && receiver->in(0)->is_CallStaticJava()) {
 346             CallStaticJavaNode* csj = receiver->in(0)->as_CallStaticJava();
 347             ciMethod* m = csj->method();
 348             if (m != NULL &&
 349                 (m->intrinsic_id() == vmIntrinsics::_StringBuffer_toString ||
 350                  m->intrinsic_id() == vmIntrinsics::_StringBuilder_toString))
 351               // Delay String.<init>(new SB())
 352               return true;
 353           }
 354           return false;
 355         }
 356 
 357       default:
 358         return false;
 359     }
 360   }
 361   return false;
 362 }
 363 
 364 bool Compile::should_delay_boxing_inlining(ciMethod* call_method, JVMState* jvms) {
 365   if (eliminate_boxing() && call_method->is_boxing_method()) {
 366     set_has_boxed_value(true);
 367     return aggressive_unboxing();
 368   }
 369   return false;
 370 }
 371 
 372 // uncommon-trap call-sites where callee is unloaded, uninitialized or will not link
 373 bool Parse::can_not_compile_call_site(ciMethod *dest_method, ciInstanceKlass* klass) {
 374   // Additional inputs to consider...
 375   // bc      = bc()
 376   // caller  = method()
 377   // iter().get_method_holder_index()
 378   assert( dest_method->is_loaded(), "ciTypeFlow should not let us get here" );
 379   // Interface classes can be loaded & linked and never get around to
 380   // being initialized.  Uncommon-trap for not-initialized static or
 381   // v-calls.  Let interface calls happen.
 382   ciInstanceKlass* holder_klass = dest_method->holder();
 383   if (!holder_klass->is_being_initialized() &&
 384       !holder_klass->is_initialized() &&
 385       !holder_klass->is_interface()) {
 386     uncommon_trap(Deoptimization::Reason_uninitialized,
 387                   Deoptimization::Action_reinterpret,
 388                   holder_klass);
 389     return true;
 390   }
 391 
 392   assert(dest_method->is_loaded(), "dest_method: typeflow responsibility");
 393   return false;
 394 }
 395 
 396 
 397 //------------------------------do_call----------------------------------------
 398 // Handle your basic call.  Inline if we can & want to, else just setup call.
 399 void Parse::do_call() {
 400   // It's likely we are going to add debug info soon.
 401   // Also, if we inline a guy who eventually needs debug info for this JVMS,
 402   // our contribution to it is cleaned up right here.
 403   kill_dead_locals();
 404 
 405   C->print_inlining_assert_ready();
 406 
 407   // Set frequently used booleans
 408   const bool is_virtual = bc() == Bytecodes::_invokevirtual;
 409   const bool is_virtual_or_interface = is_virtual || bc() == Bytecodes::_invokeinterface;
 410   const bool has_receiver = Bytecodes::has_receiver(bc());
 411 
 412   // Find target being called
 413   bool             will_link;
 414   ciSignature*     declared_signature = NULL;
 415   ciMethod*        orig_callee  = iter().get_method(will_link, &declared_signature);  // callee in the bytecode
 416   ciInstanceKlass* holder_klass = orig_callee->holder();
 417   ciKlass*         holder       = iter().get_declared_method_holder();
 418   ciInstanceKlass* klass = ciEnv::get_instance_klass_for_declared_method_holder(holder);
 419   assert(declared_signature != NULL, "cannot be null");
 420 
 421   // uncommon-trap when callee is unloaded, uninitialized or will not link
 422   // bailout when too many arguments for register representation
 423   if (!will_link || can_not_compile_call_site(orig_callee, klass)) {
 424 #ifndef PRODUCT
 425     if (PrintOpto && (Verbose || WizardMode)) {
 426       method()->print_name(); tty->print_cr(" can not compile call at bci %d to:", bci());
 427       orig_callee->print_name(); tty->cr();
 428     }
 429 #endif
 430     return;
 431   }
 432   assert(holder_klass->is_loaded(), "");
 433   //assert((bc_callee->is_static() || is_invokedynamic) == !has_receiver , "must match bc");  // XXX invokehandle (cur_bc_raw)
 434   // Note: this takes into account invokeinterface of methods declared in java/lang/Object,
 435   // which should be invokevirtuals but according to the VM spec may be invokeinterfaces
 436   assert(holder_klass->is_interface() || holder_klass->super() == NULL || (bc() != Bytecodes::_invokeinterface), "must match bc");
 437   // Note:  In the absence of miranda methods, an abstract class K can perform
 438   // an invokevirtual directly on an interface method I.m if K implements I.
 439 
 440   // orig_callee is the resolved callee which's signature includes the
 441   // appendix argument.
 442   const int nargs = orig_callee->arg_size();
 443   const bool is_signature_polymorphic = MethodHandles::is_signature_polymorphic(orig_callee->intrinsic_id());
 444 
 445   // Push appendix argument (MethodType, CallSite, etc.), if one.
 446   if (iter().has_appendix()) {
 447     ciObject* appendix_arg = iter().get_appendix();
 448     const TypeOopPtr* appendix_arg_type = TypeOopPtr::make_from_constant(appendix_arg);
 449     Node* appendix_arg_node = _gvn.makecon(appendix_arg_type);
 450     push(appendix_arg_node);
 451   }
 452 
 453   // ---------------------
 454   // Does Class Hierarchy Analysis reveal only a single target of a v-call?
 455   // Then we may inline or make a static call, but become dependent on there being only 1 target.
 456   // Does the call-site type profile reveal only one receiver?
 457   // Then we may introduce a run-time check and inline on the path where it succeeds.
 458   // The other path may uncommon_trap, check for another receiver, or do a v-call.
 459 
 460   // Try to get the most accurate receiver type
 461   ciMethod* callee             = orig_callee;
 462   int       vtable_index       = Method::invalid_vtable_index;
 463   bool      call_does_dispatch = false;
 464 
 465   // Speculative type of the receiver if any
 466   ciKlass* speculative_receiver_type = NULL;
 467   if (is_virtual_or_interface) {
 468     Node* receiver_node             = stack(sp() - nargs);
 469     const TypeOopPtr* receiver_type = _gvn.type(receiver_node)->isa_oopptr();
 470     // call_does_dispatch and vtable_index are out-parameters.  They might be changed.
 471     // For arrays, klass below is Object. When vtable calls are used,
 472     // resolving the call with Object would allow an illegal call to
 473     // finalize() on an array. We use holder instead: illegal calls to
 474     // finalize() won't be compiled as vtable calls (IC call
 475     // resolution will catch the illegal call) and the few legal calls
 476     // on array types won't be either.
 477     callee = C->optimize_virtual_call(method(), bci(), klass, holder, orig_callee,
 478                                       receiver_type, is_virtual,
 479                                       call_does_dispatch, vtable_index);  // out-parameters
 480     speculative_receiver_type = receiver_type != NULL ? receiver_type->speculative_type() : NULL;
 481   }
 482 
 483   // Note:  It's OK to try to inline a virtual call.
 484   // The call generator will not attempt to inline a polymorphic call
 485   // unless it knows how to optimize the receiver dispatch.
 486   bool try_inline = (C->do_inlining() || InlineAccessors);
 487 
 488   // ---------------------
 489   dec_sp(nargs);              // Temporarily pop args for JVM state of call
 490   JVMState* jvms = sync_jvms();
 491 
 492   // ---------------------
 493   // Decide call tactic.
 494   // This call checks with CHA, the interpreter profile, intrinsics table, etc.
 495   // It decides whether inlining is desirable or not.
 496   CallGenerator* cg = C->call_generator(callee, vtable_index, call_does_dispatch, jvms, try_inline, prof_factor(), speculative_receiver_type);
 497 
 498   // NOTE:  Don't use orig_callee and callee after this point!  Use cg->method() instead.
 499   orig_callee = callee = NULL;
 500 
 501   // ---------------------
 502   // Round double arguments before call
 503   round_double_arguments(cg->method());
 504 
 505   // Feed profiling data for arguments to the type system so it can
 506   // propagate it as speculative types
 507   record_profiled_arguments_for_speculation(cg->method(), bc());
 508 
 509 #ifndef PRODUCT
 510   // bump global counters for calls
 511   count_compiled_calls(/*at_method_entry*/ false, cg->is_inline());
 512 
 513   // Record first part of parsing work for this call
 514   parse_histogram()->record_change();
 515 #endif // not PRODUCT
 516 
 517   assert(jvms == this->jvms(), "still operating on the right JVMS");
 518   assert(jvms_in_sync(),       "jvms must carry full info into CG");
 519 
 520   // save across call, for a subsequent cast_not_null.
 521   Node* receiver = has_receiver ? argument(0) : NULL;
 522 
 523   // The extra CheckCastPP for speculative types mess with PhaseStringOpts
 524   if (receiver != NULL && !call_does_dispatch && !cg->is_string_late_inline()) {
 525     // Feed profiling data for a single receiver to the type system so
 526     // it can propagate it as a speculative type
 527     receiver = record_profiled_receiver_for_speculation(receiver);
 528   }
 529 
 530   // Bump method data counters (We profile *before* the call is made
 531   // because exceptions don't return to the call site.)
 532   profile_call(receiver);
 533 
 534   JVMState* new_jvms = cg->generate(jvms);
 535   if (new_jvms == NULL) {
 536     // When inlining attempt fails (e.g., too many arguments),
 537     // it may contaminate the current compile state, making it
 538     // impossible to pull back and try again.  Once we call
 539     // cg->generate(), we are committed.  If it fails, the whole
 540     // compilation task is compromised.
 541     if (failing())  return;
 542 
 543     // This can happen if a library intrinsic is available, but refuses
 544     // the call site, perhaps because it did not match a pattern the
 545     // intrinsic was expecting to optimize. Should always be possible to
 546     // get a normal java call that may inline in that case
 547     cg = C->call_generator(cg->method(), vtable_index, call_does_dispatch, jvms, try_inline, prof_factor(), speculative_receiver_type, /* allow_intrinsics= */ false);
 548     new_jvms = cg->generate(jvms);
 549     if (new_jvms == NULL) {
 550       guarantee(failing(), "call failed to generate:  calls should work");
 551       return;
 552     }
 553   }
 554 
 555   if (cg->is_inline()) {
 556     // Accumulate has_loops estimate
 557     C->set_has_loops(C->has_loops() || cg->method()->has_loops());
 558     C->env()->notice_inlined_method(cg->method());
 559   }
 560 
 561   // Reset parser state from [new_]jvms, which now carries results of the call.
 562   // Return value (if any) is already pushed on the stack by the cg.
 563   add_exception_states_from(new_jvms);
 564   if (new_jvms->map()->control() == top()) {
 565     stop_and_kill_map();
 566   } else {
 567     assert(new_jvms->same_calls_as(jvms), "method/bci left unchanged");
 568     set_jvms(new_jvms);
 569   }
 570 
 571   if (!stopped()) {
 572     // This was some sort of virtual call, which did a null check for us.
 573     // Now we can assert receiver-not-null, on the normal return path.
 574     if (receiver != NULL && cg->is_virtual()) {
 575       Node* cast = cast_not_null(receiver);
 576       // %%% assert(receiver == cast, "should already have cast the receiver");
 577     }
 578 
 579     // Round double result after a call from strict to non-strict code
 580     round_double_result(cg->method());
 581 
 582     ciType* rtype = cg->method()->return_type();
 583     ciType* ctype = declared_signature->return_type();
 584 
 585     if (Bytecodes::has_optional_appendix(iter().cur_bc_raw()) || is_signature_polymorphic) {
 586       // Be careful here with return types.
 587       if (ctype != rtype) {
 588         BasicType rt = rtype->basic_type();
 589         BasicType ct = ctype->basic_type();
 590         if (ct == T_VOID) {
 591           // It's OK for a method  to return a value that is discarded.
 592           // The discarding does not require any special action from the caller.
 593           // The Java code knows this, at VerifyType.isNullConversion.
 594           pop_node(rt);  // whatever it was, pop it
 595         } else if (rt == T_INT || is_subword_type(rt)) {
 596           // Nothing.  These cases are handled in lambda form bytecode.
 597           assert(ct == T_INT || is_subword_type(ct), err_msg_res("must match: rt=%s, ct=%s", type2name(rt), type2name(ct)));
 598         } else if (rt == T_OBJECT || rt == T_ARRAY) {
 599           assert(ct == T_OBJECT || ct == T_ARRAY, err_msg_res("rt=%s, ct=%s", type2name(rt), type2name(ct)));
 600           if (ctype->is_loaded()) {
 601             const TypeOopPtr* arg_type = TypeOopPtr::make_from_klass(rtype->as_klass());
 602             const Type*       sig_type = TypeOopPtr::make_from_klass(ctype->as_klass());
 603             if (arg_type != NULL && !arg_type->higher_equal(sig_type)) {
 604               Node* retnode = pop();
 605               Node* cast_obj = _gvn.transform(new CheckCastPPNode(control(), retnode, sig_type));
 606               push(cast_obj);
 607             }
 608           }
 609         } else {
 610           assert(rt == ct, err_msg_res("unexpected mismatch: rt=%s, ct=%s", type2name(rt), type2name(ct)));
 611           // push a zero; it's better than getting an oop/int mismatch
 612           pop_node(rt);
 613           Node* retnode = zerocon(ct);
 614           push_node(ct, retnode);
 615         }
 616         // Now that the value is well-behaved, continue with the call-site type.
 617         rtype = ctype;
 618       }
 619     } else {
 620       // Symbolic resolution enforces the types to be the same.
 621       // NOTE: We must relax the assert for unloaded types because two
 622       // different ciType instances of the same unloaded class type
 623       // can appear to be "loaded" by different loaders (depending on
 624       // the accessing class).
 625       assert(!rtype->is_loaded() || !ctype->is_loaded() || rtype == ctype,
 626              err_msg_res("mismatched return types: rtype=%s, ctype=%s", rtype->name(), ctype->name()));
 627     }
 628 
 629     // If the return type of the method is not loaded, assert that the
 630     // value we got is a null.  Otherwise, we need to recompile.
 631     if (!rtype->is_loaded()) {
 632 #ifndef PRODUCT
 633       if (PrintOpto && (Verbose || WizardMode)) {
 634         method()->print_name(); tty->print_cr(" asserting nullness of result at bci: %d", bci());
 635         cg->method()->print_name(); tty->cr();
 636       }
 637 #endif
 638       if (C->log() != NULL) {
 639         C->log()->elem("assert_null reason='return' klass='%d'",
 640                        C->log()->identify(rtype));
 641       }
 642       // If there is going to be a trap, put it at the next bytecode:
 643       set_bci(iter().next_bci());
 644       null_assert(peek());
 645       set_bci(iter().cur_bci()); // put it back
 646     }
 647     BasicType ct = ctype->basic_type();
 648     if (ct == T_OBJECT || ct == T_ARRAY) {
 649       record_profiled_return_for_speculation();
 650     }
 651   }
 652 
 653   // Restart record of parsing work after possible inlining of call
 654 #ifndef PRODUCT
 655   parse_histogram()->set_initial_state(bc());
 656 #endif
 657 }
 658 
 659 //---------------------------catch_call_exceptions-----------------------------
 660 // Put a Catch and CatchProj nodes behind a just-created call.
 661 // Send their caught exceptions to the proper handler.
 662 // This may be used after a call to the rethrow VM stub,
 663 // when it is needed to process unloaded exception classes.
 664 void Parse::catch_call_exceptions(ciExceptionHandlerStream& handlers) {
 665   // Exceptions are delivered through this channel:
 666   Node* i_o = this->i_o();
 667 
 668   // Add a CatchNode.
 669   GrowableArray<int>* bcis = new (C->node_arena()) GrowableArray<int>(C->node_arena(), 8, 0, -1);
 670   GrowableArray<const Type*>* extypes = new (C->node_arena()) GrowableArray<const Type*>(C->node_arena(), 8, 0, NULL);
 671   GrowableArray<int>* saw_unloaded = new (C->node_arena()) GrowableArray<int>(C->node_arena(), 8, 0, 0);
 672 
 673   for (; !handlers.is_done(); handlers.next()) {
 674     ciExceptionHandler* h        = handlers.handler();
 675     int                 h_bci    = h->handler_bci();
 676     ciInstanceKlass*    h_klass  = h->is_catch_all() ? env()->Throwable_klass() : h->catch_klass();
 677     // Do not introduce unloaded exception types into the graph:
 678     if (!h_klass->is_loaded()) {
 679       if (saw_unloaded->contains(h_bci)) {
 680         /* We've already seen an unloaded exception with h_bci,
 681            so don't duplicate. Duplication will cause the CatchNode to be
 682            unnecessarily large. See 4713716. */
 683         continue;
 684       } else {
 685         saw_unloaded->append(h_bci);
 686       }
 687     }
 688     const Type*         h_extype = TypeOopPtr::make_from_klass(h_klass);
 689     // (We use make_from_klass because it respects UseUniqueSubclasses.)
 690     h_extype = h_extype->join(TypeInstPtr::NOTNULL);
 691     assert(!h_extype->empty(), "sanity");
 692     // Note:  It's OK if the BCIs repeat themselves.
 693     bcis->append(h_bci);
 694     extypes->append(h_extype);
 695   }
 696 
 697   int len = bcis->length();
 698   CatchNode *cn = new CatchNode(control(), i_o, len+1);
 699   Node *catch_ = _gvn.transform(cn);
 700 
 701   // now branch with the exception state to each of the (potential)
 702   // handlers
 703   for(int i=0; i < len; i++) {
 704     // Setup JVM state to enter the handler.
 705     PreserveJVMState pjvms(this);
 706     // Locals are just copied from before the call.
 707     // Get control from the CatchNode.
 708     int handler_bci = bcis->at(i);
 709     Node* ctrl = _gvn.transform( new CatchProjNode(catch_, i+1,handler_bci));
 710     // This handler cannot happen?
 711     if (ctrl == top())  continue;
 712     set_control(ctrl);
 713 
 714     // Create exception oop
 715     const TypeInstPtr* extype = extypes->at(i)->is_instptr();
 716     Node *ex_oop = _gvn.transform(new CreateExNode(extypes->at(i), ctrl, i_o));
 717 
 718     // Handle unloaded exception classes.
 719     if (saw_unloaded->contains(handler_bci)) {
 720       // An unloaded exception type is coming here.  Do an uncommon trap.
 721 #ifndef PRODUCT
 722       // We do not expect the same handler bci to take both cold unloaded
 723       // and hot loaded exceptions.  But, watch for it.
 724       if ((Verbose || WizardMode) && extype->is_loaded()) {
 725         tty->print("Warning: Handler @%d takes mixed loaded/unloaded exceptions in ", bci());
 726         method()->print_name(); tty->cr();
 727       } else if (PrintOpto && (Verbose || WizardMode)) {
 728         tty->print("Bailing out on unloaded exception type ");
 729         extype->klass()->print_name();
 730         tty->print(" at bci:%d in ", bci());
 731         method()->print_name(); tty->cr();
 732       }
 733 #endif
 734       // Emit an uncommon trap instead of processing the block.
 735       set_bci(handler_bci);
 736       push_ex_oop(ex_oop);
 737       uncommon_trap(Deoptimization::Reason_unloaded,
 738                     Deoptimization::Action_reinterpret,
 739                     extype->klass(), "!loaded exception");
 740       set_bci(iter().cur_bci()); // put it back
 741       continue;
 742     }
 743 
 744     // go to the exception handler
 745     if (handler_bci < 0) {     // merge with corresponding rethrow node
 746       throw_to_exit(make_exception_state(ex_oop));
 747     } else {                      // Else jump to corresponding handle
 748       push_ex_oop(ex_oop);        // Clear stack and push just the oop.
 749       merge_exception(handler_bci);
 750     }
 751   }
 752 
 753   // The first CatchProj is for the normal return.
 754   // (Note:  If this is a call to rethrow_Java, this node goes dead.)
 755   set_control(_gvn.transform( new CatchProjNode(catch_, CatchProjNode::fall_through_index, CatchProjNode::no_handler_bci)));
 756 }
 757 
 758 
 759 //----------------------------catch_inline_exceptions--------------------------
 760 // Handle all exceptions thrown by an inlined method or individual bytecode.
 761 // Common case 1: we have no handler, so all exceptions merge right into
 762 // the rethrow case.
 763 // Case 2: we have some handlers, with loaded exception klasses that have
 764 // no subklasses.  We do a Deutsch-Shiffman style type-check on the incoming
 765 // exception oop and branch to the handler directly.
 766 // Case 3: We have some handlers with subklasses or are not loaded at
 767 // compile-time.  We have to call the runtime to resolve the exception.
 768 // So we insert a RethrowCall and all the logic that goes with it.
 769 void Parse::catch_inline_exceptions(SafePointNode* ex_map) {
 770   // Caller is responsible for saving away the map for normal control flow!
 771   assert(stopped(), "call set_map(NULL) first");
 772   assert(method()->has_exception_handlers(), "don't come here w/o work to do");
 773 
 774   Node* ex_node = saved_ex_oop(ex_map);
 775   if (ex_node == top()) {
 776     // No action needed.
 777     return;
 778   }
 779   const TypeInstPtr* ex_type = _gvn.type(ex_node)->isa_instptr();
 780   NOT_PRODUCT(if (ex_type==NULL) tty->print_cr("*** Exception not InstPtr"));
 781   if (ex_type == NULL)
 782     ex_type = TypeOopPtr::make_from_klass(env()->Throwable_klass())->is_instptr();
 783 
 784   // determine potential exception handlers
 785   ciExceptionHandlerStream handlers(method(), bci(),
 786                                     ex_type->klass()->as_instance_klass(),
 787                                     ex_type->klass_is_exact());
 788 
 789   // Start executing from the given throw state.  (Keep its stack, for now.)
 790   // Get the exception oop as known at compile time.
 791   ex_node = use_exception_state(ex_map);
 792 
 793   // Get the exception oop klass from its header
 794   Node* ex_klass_node = NULL;
 795   if (has_ex_handler() && !ex_type->klass_is_exact()) {
 796     Node* p = basic_plus_adr( ex_node, ex_node, oopDesc::klass_offset_in_bytes());
 797     ex_klass_node = _gvn.transform( LoadKlassNode::make(_gvn, immutable_memory(), p, TypeInstPtr::KLASS, TypeKlassPtr::OBJECT) );
 798 
 799     // Compute the exception klass a little more cleverly.
 800     // Obvious solution is to simple do a LoadKlass from the 'ex_node'.
 801     // However, if the ex_node is a PhiNode, I'm going to do a LoadKlass for
 802     // each arm of the Phi.  If I know something clever about the exceptions
 803     // I'm loading the class from, I can replace the LoadKlass with the
 804     // klass constant for the exception oop.
 805     if( ex_node->is_Phi() ) {
 806       ex_klass_node = new PhiNode( ex_node->in(0), TypeKlassPtr::OBJECT );
 807       for( uint i = 1; i < ex_node->req(); i++ ) {
 808         Node* p = basic_plus_adr( ex_node->in(i), ex_node->in(i), oopDesc::klass_offset_in_bytes() );
 809         Node* k = _gvn.transform( LoadKlassNode::make(_gvn, immutable_memory(), p, TypeInstPtr::KLASS, TypeKlassPtr::OBJECT) );
 810         ex_klass_node->init_req( i, k );
 811       }
 812       _gvn.set_type(ex_klass_node, TypeKlassPtr::OBJECT);
 813 
 814     }
 815   }
 816 
 817   // Scan the exception table for applicable handlers.
 818   // If none, we can call rethrow() and be done!
 819   // If precise (loaded with no subklasses), insert a D.S. style
 820   // pointer compare to the correct handler and loop back.
 821   // If imprecise, switch to the Rethrow VM-call style handling.
 822 
 823   int remaining = handlers.count_remaining();
 824 
 825   // iterate through all entries sequentially
 826   for (;!handlers.is_done(); handlers.next()) {
 827     ciExceptionHandler* handler = handlers.handler();
 828 
 829     if (handler->is_rethrow()) {
 830       // If we fell off the end of the table without finding an imprecise
 831       // exception klass (and without finding a generic handler) then we
 832       // know this exception is not handled in this method.  We just rethrow
 833       // the exception into the caller.
 834       throw_to_exit(make_exception_state(ex_node));
 835       return;
 836     }
 837 
 838     // exception handler bci range covers throw_bci => investigate further
 839     int handler_bci = handler->handler_bci();
 840 
 841     if (remaining == 1) {
 842       push_ex_oop(ex_node);        // Push exception oop for handler
 843 #ifndef PRODUCT
 844       if (PrintOpto && WizardMode) {
 845         tty->print_cr("  Catching every inline exception bci:%d -> handler_bci:%d", bci(), handler_bci);
 846       }
 847 #endif
 848       merge_exception(handler_bci); // jump to handler
 849       return;                   // No more handling to be done here!
 850     }
 851 
 852     // Get the handler's klass
 853     ciInstanceKlass* klass = handler->catch_klass();
 854 
 855     if (!klass->is_loaded()) {  // klass is not loaded?
 856       // fall through into catch_call_exceptions which will emit a
 857       // handler with an uncommon trap.
 858       break;
 859     }
 860 
 861     if (klass->is_interface())  // should not happen, but...
 862       break;                    // bail out
 863 
 864     // Check the type of the exception against the catch type
 865     const TypeKlassPtr *tk = TypeKlassPtr::make(klass);
 866     Node* con = _gvn.makecon(tk);
 867     Node* not_subtype_ctrl = gen_subtype_check(ex_klass_node, con);
 868     if (!stopped()) {
 869       PreserveJVMState pjvms(this);
 870       const TypeInstPtr* tinst = TypeOopPtr::make_from_klass_unique(klass)->cast_to_ptr_type(TypePtr::NotNull)->is_instptr();
 871       assert(klass->has_subklass() || tinst->klass_is_exact(), "lost exactness");
 872       Node* ex_oop = _gvn.transform(new CheckCastPPNode(control(), ex_node, tinst));
 873       push_ex_oop(ex_oop);      // Push exception oop for handler
 874 #ifndef PRODUCT
 875       if (PrintOpto && WizardMode) {
 876         tty->print("  Catching inline exception bci:%d -> handler_bci:%d -- ", bci(), handler_bci);
 877         klass->print_name();
 878         tty->cr();
 879       }
 880 #endif
 881       merge_exception(handler_bci);
 882     }
 883     set_control(not_subtype_ctrl);
 884 
 885     // Come here if exception does not match handler.
 886     // Carry on with more handler checks.
 887     --remaining;
 888   }
 889 
 890   assert(!stopped(), "you should return if you finish the chain");
 891 
 892   // Oops, need to call into the VM to resolve the klasses at runtime.
 893   // Note:  This call must not deoptimize, since it is not a real at this bci!
 894   kill_dead_locals();
 895 
 896   make_runtime_call(RC_NO_LEAF | RC_MUST_THROW,
 897                     OptoRuntime::rethrow_Type(),
 898                     OptoRuntime::rethrow_stub(),
 899                     NULL, NULL,
 900                     ex_node);
 901 
 902   // Rethrow is a pure call, no side effects, only a result.
 903   // The result cannot be allocated, so we use I_O
 904 
 905   // Catch exceptions from the rethrow
 906   catch_call_exceptions(handlers);
 907 }
 908 
 909 
 910 // (Note:  Moved add_debug_info into GraphKit::add_safepoint_edges.)
 911 
 912 
 913 #ifndef PRODUCT
 914 void Parse::count_compiled_calls(bool at_method_entry, bool is_inline) {
 915   if( CountCompiledCalls ) {
 916     if( at_method_entry ) {
 917       // bump invocation counter if top method (for statistics)
 918       if (CountCompiledCalls && depth() == 1) {
 919         const TypePtr* addr_type = TypeMetadataPtr::make(method());
 920         Node* adr1 = makecon(addr_type);
 921         Node* adr2 = basic_plus_adr(adr1, adr1, in_bytes(Method::compiled_invocation_counter_offset()));
 922         increment_counter(adr2);
 923       }
 924     } else if (is_inline) {
 925       switch (bc()) {
 926       case Bytecodes::_invokevirtual:   increment_counter(SharedRuntime::nof_inlined_calls_addr()); break;
 927       case Bytecodes::_invokeinterface: increment_counter(SharedRuntime::nof_inlined_interface_calls_addr()); break;
 928       case Bytecodes::_invokestatic:
 929       case Bytecodes::_invokedynamic:
 930       case Bytecodes::_invokespecial:   increment_counter(SharedRuntime::nof_inlined_static_calls_addr()); break;
 931       default: fatal("unexpected call bytecode");
 932       }
 933     } else {
 934       switch (bc()) {
 935       case Bytecodes::_invokevirtual:   increment_counter(SharedRuntime::nof_normal_calls_addr()); break;
 936       case Bytecodes::_invokeinterface: increment_counter(SharedRuntime::nof_interface_calls_addr()); break;
 937       case Bytecodes::_invokestatic:
 938       case Bytecodes::_invokedynamic:
 939       case Bytecodes::_invokespecial:   increment_counter(SharedRuntime::nof_static_calls_addr()); break;
 940       default: fatal("unexpected call bytecode");
 941       }
 942     }
 943   }
 944 }
 945 #endif //PRODUCT
 946 
 947 
 948 ciMethod* Compile::optimize_virtual_call(ciMethod* caller, int bci, ciInstanceKlass* klass,
 949                                          ciKlass* holder, ciMethod* callee,
 950                                          const TypeOopPtr* receiver_type, bool is_virtual,
 951                                          bool& call_does_dispatch, int& vtable_index) {
 952   // Set default values for out-parameters.
 953   call_does_dispatch = true;
 954   vtable_index       = Method::invalid_vtable_index;
 955 
 956   // Choose call strategy.
 957   ciMethod* optimized_virtual_method = optimize_inlining(caller, bci, klass, callee, receiver_type);
 958 
 959   // Have the call been sufficiently improved such that it is no longer a virtual?
 960   if (optimized_virtual_method != NULL) {
 961     callee             = optimized_virtual_method;
 962     call_does_dispatch = false;
 963   } else if (!UseInlineCaches && is_virtual && callee->is_loaded()) {
 964     // We can make a vtable call at this site
 965     vtable_index = callee->resolve_vtable_index(caller->holder(), holder);
 966   }
 967   return callee;
 968 }
 969 
 970 // Identify possible target method and inlining style
 971 ciMethod* Compile::optimize_inlining(ciMethod* caller, int bci, ciInstanceKlass* klass,
 972                                      ciMethod* callee, const TypeOopPtr* receiver_type) {
 973   // only use for virtual or interface calls
 974 
 975   // If it is obviously final, do not bother to call find_monomorphic_target,
 976   // because the class hierarchy checks are not needed, and may fail due to
 977   // incompletely loaded classes.  Since we do our own class loading checks
 978   // in this module, we may confidently bind to any method.
 979   if (callee->can_be_statically_bound()) {
 980     return callee;
 981   }
 982 
 983   // Attempt to improve the receiver
 984   bool actual_receiver_is_exact = false;
 985   ciInstanceKlass* actual_receiver = klass;
 986   if (receiver_type != NULL) {
 987     // Array methods are all inherited from Object, and are monomorphic.
 988     // finalize() call on array is not allowed.
 989     if (receiver_type->isa_aryptr() &&
 990         callee->holder() == env()->Object_klass() &&
 991         callee->name() != ciSymbol::finalize_method_name()) {
 992       return callee;
 993     }
 994 
 995     // All other interesting cases are instance klasses.
 996     if (!receiver_type->isa_instptr()) {
 997       return NULL;
 998     }
 999 
1000     ciInstanceKlass *ikl = receiver_type->klass()->as_instance_klass();
1001     if (ikl->is_loaded() && ikl->is_initialized() && !ikl->is_interface() &&
1002         (ikl == actual_receiver || ikl->is_subtype_of(actual_receiver))) {
1003       // ikl is a same or better type than the original actual_receiver,
1004       // e.g. static receiver from bytecodes.
1005       actual_receiver = ikl;
1006       // Is the actual_receiver exact?
1007       actual_receiver_is_exact = receiver_type->klass_is_exact();
1008     }
1009   }
1010 
1011   ciInstanceKlass*   calling_klass = caller->holder();
1012   ciMethod* cha_monomorphic_target = callee->find_monomorphic_target(calling_klass, klass, actual_receiver);
1013   if (cha_monomorphic_target != NULL) {
1014     assert(!cha_monomorphic_target->is_abstract(), "");
1015     // Look at the method-receiver type.  Does it add "too much information"?
1016     ciKlass*    mr_klass = cha_monomorphic_target->holder();
1017     const Type* mr_type  = TypeInstPtr::make(TypePtr::BotPTR, mr_klass);
1018     if (receiver_type == NULL || !receiver_type->higher_equal(mr_type)) {
1019       // Calling this method would include an implicit cast to its holder.
1020       // %%% Not yet implemented.  Would throw minor asserts at present.
1021       // %%% The most common wins are already gained by +UseUniqueSubclasses.
1022       // To fix, put the higher_equal check at the call of this routine,
1023       // and add a CheckCastPP to the receiver.
1024       if (TraceDependencies) {
1025         tty->print_cr("found unique CHA method, but could not cast up");
1026         tty->print("  method  = ");
1027         cha_monomorphic_target->print();
1028         tty->cr();
1029       }
1030       if (log() != NULL) {
1031         log()->elem("missed_CHA_opportunity klass='%d' method='%d'",
1032                        log()->identify(klass),
1033                        log()->identify(cha_monomorphic_target));
1034       }
1035       cha_monomorphic_target = NULL;
1036     }
1037   }
1038   if (cha_monomorphic_target != NULL) {
1039     // Hardwiring a virtual.
1040     // If we inlined because CHA revealed only a single target method,
1041     // then we are dependent on that target method not getting overridden
1042     // by dynamic class loading.  Be sure to test the "static" receiver
1043     // dest_method here, as opposed to the actual receiver, which may
1044     // falsely lead us to believe that the receiver is final or private.
1045     dependencies()->assert_unique_concrete_method(actual_receiver, cha_monomorphic_target);
1046     return cha_monomorphic_target;
1047   }
1048 
1049   // If the type is exact, we can still bind the method w/o a vcall.
1050   // (This case comes after CHA so we can see how much extra work it does.)
1051   if (actual_receiver_is_exact) {
1052     // In case of evolution, there is a dependence on every inlined method, since each
1053     // such method can be changed when its class is redefined.
1054     ciMethod* exact_method = callee->resolve_invoke(calling_klass, actual_receiver);
1055     if (exact_method != NULL) {
1056 #ifndef PRODUCT
1057       if (PrintOpto) {
1058         tty->print("  Calling method via exact type @%d --- ", bci);
1059         exact_method->print_name();
1060         tty->cr();
1061       }
1062 #endif
1063       return exact_method;
1064     }
1065   }
1066 
1067   return NULL;
1068 }