1 /*
   2  * Copyright (c) 1997, 2017, 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 "classfile/systemDictionary.hpp"
  27 #include "code/codeCache.hpp"
  28 #include "code/compiledIC.hpp"
  29 #include "code/icBuffer.hpp"
  30 #include "code/nmethod.hpp"
  31 #include "code/vtableStubs.hpp"
  32 #include "interpreter/interpreter.hpp"
  33 #include "interpreter/linkResolver.hpp"
  34 #include "memory/metadataFactory.hpp"
  35 #include "memory/oopFactory.hpp"
  36 #include "oops/method.hpp"
  37 #include "oops/oop.inline.hpp"
  38 #include "oops/symbol.hpp"
  39 #include "runtime/icache.hpp"
  40 #include "runtime/sharedRuntime.hpp"
  41 #include "runtime/stubRoutines.hpp"
  42 #include "utilities/events.hpp"
  43 
  44 
  45 // Every time a compiled IC is changed or its type is being accessed,
  46 // either the CompiledIC_lock must be set or we must be at a safe point.
  47 
  48 //-----------------------------------------------------------------------------
  49 // Low-level access to an inline cache. Private, since they might not be
  50 // MT-safe to use.
  51 
  52 void* CompiledIC::cached_value() const {
  53   assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
  54   assert (!is_optimized(), "an optimized virtual call does not have a cached metadata");
  55 
  56   if (!is_in_transition_state()) {
  57     void* data = (void*)_value->data();
  58     // If we let the metadata value here be initialized to zero...
  59     assert(data != NULL || Universe::non_oop_word() == NULL,
  60            "no raw nulls in CompiledIC metadatas, because of patching races");
  61     return (data == (void*)Universe::non_oop_word()) ? NULL : data;
  62   } else {
  63     return InlineCacheBuffer::cached_value_for((CompiledIC *)this);
  64   }
  65 }
  66 
  67 
  68 void CompiledIC::internal_set_ic_destination(address entry_point, bool is_icstub, void* cache, bool is_icholder) {
  69   assert(entry_point != NULL, "must set legal entry point");
  70   assert(CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
  71   assert (!is_optimized() || cache == NULL, "an optimized virtual call does not have a cached metadata");
  72   assert (cache == NULL || cache != (Metadata*)badOopVal, "invalid metadata");
  73 
  74   assert(!is_icholder || is_icholder_entry(entry_point), "must be");
  75 
  76   // Don't use ic_destination for this test since that forwards
  77   // through ICBuffer instead of returning the actual current state of
  78   // the CompiledIC.
  79   if (is_icholder_entry(_ic_call->destination())) {
  80     // When patching for the ICStub case the cached value isn't
  81     // overwritten until the ICStub copied into the CompiledIC during
  82     // the next safepoint.  Make sure that the CompiledICHolder* is
  83     // marked for release at this point since it won't be identifiable
  84     // once the entry point is overwritten.
  85     InlineCacheBuffer::queue_for_release((CompiledICHolder*)_value->data());
  86   }
  87 
  88   if (TraceCompiledIC) {
  89     tty->print("  ");
  90     print_compiled_ic();
  91     tty->print(" changing destination to " INTPTR_FORMAT, p2i(entry_point));
  92     if (!is_optimized()) {
  93       tty->print(" changing cached %s to " INTPTR_FORMAT, is_icholder ? "icholder" : "metadata", p2i((address)cache));
  94     }
  95     if (is_icstub) {
  96       tty->print(" (icstub)");
  97     }
  98     tty->cr();
  99   }
 100 
 101   {
 102     MutexLockerEx pl(SafepointSynchronize::is_at_safepoint() ? NULL : Patching_lock, Mutex::_no_safepoint_check_flag);
 103 #ifdef ASSERT
 104     CodeBlob* cb = CodeCache::find_blob_unsafe(_ic_call);
 105     assert(cb != NULL && cb->is_nmethod(), "must be nmethod");
 106 #endif
 107      _ic_call->set_destination_mt_safe(entry_point);
 108   }
 109 
 110   if (is_optimized() || is_icstub) {
 111     // Optimized call sites don't have a cache value and ICStub call
 112     // sites only change the entry point.  Changing the value in that
 113     // case could lead to MT safety issues.
 114     assert(cache == NULL, "must be null");
 115     return;
 116   }
 117 
 118   if (cache == NULL)  cache = (void*)Universe::non_oop_word();
 119 
 120   _value->set_data((intptr_t)cache);
 121 }
 122 
 123 
 124 void CompiledIC::set_ic_destination(ICStub* stub) {
 125   internal_set_ic_destination(stub->code_begin(), true, NULL, false);
 126 }
 127 
 128 
 129 
 130 address CompiledIC::ic_destination() const {
 131  assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
 132  if (!is_in_transition_state()) {
 133    return _ic_call->destination();
 134  } else {
 135    return InlineCacheBuffer::ic_destination_for((CompiledIC *)this);
 136  }
 137 }
 138 
 139 
 140 bool CompiledIC::is_in_transition_state() const {
 141   assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
 142   return InlineCacheBuffer::contains(_ic_call->destination());
 143 }
 144 
 145 
 146 bool CompiledIC::is_icholder_call() const {
 147   assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
 148   return !_is_optimized && is_icholder_entry(ic_destination());
 149 }
 150 
 151 // Returns native address of 'call' instruction in inline-cache. Used by
 152 // the InlineCacheBuffer when it needs to find the stub.
 153 address CompiledIC::stub_address() const {
 154   assert(is_in_transition_state(), "should only be called when we are in a transition state");
 155   return _ic_call->destination();
 156 }
 157 
 158 // Clears the IC stub if the compiled IC is in transition state
 159 void CompiledIC::clear_ic_stub() {
 160   if (is_in_transition_state()) {
 161     ICStub* stub = ICStub_from_destination_address(stub_address());
 162     stub->clear();
 163   }
 164 }
 165 
 166 
 167 //-----------------------------------------------------------------------------
 168 // High-level access to an inline cache. Guaranteed to be MT-safe.
 169 
 170 void CompiledIC::initialize_from_iter(RelocIterator* iter) {
 171   assert(iter->addr() == _ic_call->instruction_address(), "must find ic_call");
 172 
 173   if (iter->type() == relocInfo::virtual_call_type) {
 174     virtual_call_Relocation* r = iter->virtual_call_reloc();
 175     _is_optimized = false;
 176     _value = nativeMovConstReg_at(r->cached_value());
 177   } else {
 178     assert(iter->type() == relocInfo::opt_virtual_call_type, "must be a virtual call");
 179     _is_optimized = true;
 180     _value = NULL;
 181   }
 182 }
 183 
 184 CompiledIC::CompiledIC(nmethod* nm, NativeCall* call)
 185   : _ic_call(call)
 186 {
 187   address ic_call = _ic_call->instruction_address();
 188 
 189   assert(ic_call != NULL, "ic_call address must be set");
 190   assert(nm != NULL, "must pass nmethod");
 191   assert(nm->contains(ic_call), "must be in nmethod");
 192 
 193   // Search for the ic_call at the given address.
 194   RelocIterator iter(nm, ic_call, ic_call+1);
 195   bool ret = iter.next();
 196   assert(ret == true, "relocInfo must exist at this address");
 197   assert(iter.addr() == ic_call, "must find ic_call");
 198 
 199   initialize_from_iter(&iter);
 200 }
 201 
 202 CompiledIC::CompiledIC(RelocIterator* iter)
 203   : _ic_call(nativeCall_at(iter->addr()))
 204 {
 205   address ic_call = _ic_call->instruction_address();
 206 
 207   nmethod* nm = iter->code();
 208   assert(ic_call != NULL, "ic_call address must be set");
 209   assert(nm != NULL, "must pass nmethod");
 210   assert(nm->contains(ic_call), "must be in nmethod");
 211 
 212   initialize_from_iter(iter);
 213 }
 214 
 215 bool CompiledIC::set_to_megamorphic(CallInfo* call_info, Bytecodes::Code bytecode, TRAPS) {
 216   assert(CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
 217   assert(!is_optimized(), "cannot set an optimized virtual call to megamorphic");
 218   assert(is_call_to_compiled() || is_call_to_interpreted(), "going directly to megamorphic?");
 219 
 220   address entry;
 221   if (call_info->call_kind() == CallInfo::itable_call) {
 222     assert(bytecode == Bytecodes::_invokeinterface, "");
 223     int itable_index = call_info->itable_index();
 224     entry = VtableStubs::find_itable_stub(itable_index);
 225     if (entry == false) {
 226       return false;
 227     }
 228 #ifdef ASSERT
 229     int index = call_info->resolved_method()->itable_index();
 230     assert(index == itable_index, "CallInfo pre-computes this");
 231     InstanceKlass* k = call_info->resolved_method()->method_holder();
 232     assert(k->verify_itable_index(itable_index), "sanity check");
 233 #endif //ASSERT
 234     CompiledICHolder* holder = new CompiledICHolder(call_info->resolved_method()->method_holder(),
 235                                                     call_info->resolved_klass()(), false);
 236     holder->claim();
 237     InlineCacheBuffer::create_transition_stub(this, holder, entry);
 238   } else {
 239     assert(call_info->call_kind() == CallInfo::vtable_call, "either itable or vtable");
 240     // Can be different than selected_method->vtable_index(), due to package-private etc.
 241     int vtable_index = call_info->vtable_index();
 242     assert(call_info->resolved_klass()->verify_vtable_index(vtable_index), "sanity check");
 243     entry = VtableStubs::find_vtable_stub(vtable_index);
 244     if (entry == NULL) {
 245       return false;
 246     }
 247     InlineCacheBuffer::create_transition_stub(this, NULL, entry);
 248   }
 249 
 250   if (TraceICs) {
 251     ResourceMark rm;
 252     tty->print_cr ("IC@" INTPTR_FORMAT ": to megamorphic %s entry: " INTPTR_FORMAT,
 253                    p2i(instruction_address()), call_info->selected_method()->print_value_string(), p2i(entry));
 254   }
 255 
 256   // We can't check this anymore. With lazy deopt we could have already
 257   // cleaned this IC entry before we even return. This is possible if
 258   // we ran out of space in the inline cache buffer trying to do the
 259   // set_next and we safepointed to free up space. This is a benign
 260   // race because the IC entry was complete when we safepointed so
 261   // cleaning it immediately is harmless.
 262   // assert(is_megamorphic(), "sanity check");
 263   return true;
 264 }
 265 
 266 
 267 // true if destination is megamorphic stub
 268 bool CompiledIC::is_megamorphic() const {
 269   assert(CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
 270   assert(!is_optimized(), "an optimized call cannot be megamorphic");
 271 
 272   // Cannot rely on cached_value. It is either an interface or a method.
 273   return VtableStubs::entry_point(ic_destination()) != NULL;
 274 }
 275 
 276 bool CompiledIC::is_call_to_compiled() const {
 277   assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
 278 
 279   // Use unsafe, since an inline cache might point to a zombie method. However, the zombie
 280   // method is guaranteed to still exist, since we only remove methods after all inline caches
 281   // has been cleaned up
 282   CodeBlob* cb = CodeCache::find_blob_unsafe(ic_destination());
 283   bool is_monomorphic = (cb != NULL && cb->is_nmethod());
 284   // Check that the cached_value is a klass for non-optimized monomorphic calls
 285   // This assertion is invalid for compiler1: a call that does not look optimized (no static stub) can be used
 286   // for calling directly to vep without using the inline cache (i.e., cached_value == NULL)
 287 #ifdef ASSERT
 288   CodeBlob* caller = CodeCache::find_blob_unsafe(instruction_address());
 289   bool is_c1_method = caller->is_compiled_by_c1();
 290   assert( is_c1_method ||
 291          !is_monomorphic ||
 292          is_optimized() ||
 293          !caller->is_alive() ||
 294          (cached_metadata() != NULL && cached_metadata()->is_klass()), "sanity check");
 295 #endif // ASSERT
 296   return is_monomorphic;
 297 }
 298 
 299 
 300 bool CompiledIC::is_call_to_interpreted() const {
 301   assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
 302   // Call to interpreter if destination is either calling to a stub (if it
 303   // is optimized), or calling to an I2C blob
 304   bool is_call_to_interpreted = false;
 305   if (!is_optimized()) {
 306     // must use unsafe because the destination can be a zombie (and we're cleaning)
 307     // and the print_compiled_ic code wants to know if site (in the non-zombie)
 308     // is to the interpreter.
 309     CodeBlob* cb = CodeCache::find_blob_unsafe(ic_destination());
 310     is_call_to_interpreted = (cb != NULL && cb->is_adapter_blob());
 311     assert(!is_call_to_interpreted || (is_icholder_call() && cached_icholder() != NULL), "sanity check");
 312   } else {
 313     // Check if we are calling into our own codeblob (i.e., to a stub)
 314     CodeBlob* cb = CodeCache::find_blob(_ic_call->instruction_address());
 315     address dest = ic_destination();
 316 #ifdef ASSERT
 317     {
 318       CodeBlob* db = CodeCache::find_blob_unsafe(dest);
 319       assert(!db->is_adapter_blob(), "must use stub!");
 320     }
 321 #endif /* ASSERT */
 322     is_call_to_interpreted = cb->contains(dest);
 323   }
 324   return is_call_to_interpreted;
 325 }
 326 
 327 
 328 void CompiledIC::set_to_clean(bool in_use) {
 329   assert(SafepointSynchronize::is_at_safepoint() || CompiledIC_lock->is_locked() , "MT-unsafe call");
 330   if (TraceInlineCacheClearing || TraceICs) {
 331     tty->print_cr("IC@" INTPTR_FORMAT ": set to clean", p2i(instruction_address()));
 332     print();
 333   }
 334 
 335   address entry;
 336   if (is_optimized()) {
 337     entry = SharedRuntime::get_resolve_opt_virtual_call_stub();
 338   } else {
 339     entry = SharedRuntime::get_resolve_virtual_call_stub();
 340   }
 341 
 342   // A zombie transition will always be safe, since the metadata has already been set to NULL, so
 343   // we only need to patch the destination
 344   bool safe_transition = !in_use || is_optimized() || SafepointSynchronize::is_at_safepoint();
 345 
 346   if (safe_transition) {
 347     // Kill any leftover stub we might have too
 348     clear_ic_stub();
 349     if (is_optimized()) {
 350       set_ic_destination(entry);
 351     } else {
 352       set_ic_destination_and_value(entry, (void*)NULL);
 353     }
 354   } else {
 355     // Unsafe transition - create stub.
 356     InlineCacheBuffer::create_transition_stub(this, NULL, entry);
 357   }
 358   // We can't check this anymore. With lazy deopt we could have already
 359   // cleaned this IC entry before we even return. This is possible if
 360   // we ran out of space in the inline cache buffer trying to do the
 361   // set_next and we safepointed to free up space. This is a benign
 362   // race because the IC entry was complete when we safepointed so
 363   // cleaning it immediately is harmless.
 364   // assert(is_clean(), "sanity check");
 365 }
 366 
 367 
 368 bool CompiledIC::is_clean() const {
 369   assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
 370   bool is_clean = false;
 371   address dest = ic_destination();
 372   is_clean = dest == SharedRuntime::get_resolve_opt_virtual_call_stub() ||
 373              dest == SharedRuntime::get_resolve_virtual_call_stub();
 374   assert(!is_clean || is_optimized() || cached_value() == NULL, "sanity check");
 375   return is_clean;
 376 }
 377 
 378 
 379 void CompiledIC::set_to_monomorphic(CompiledICInfo& info) {
 380   assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
 381   // Updating a cache to the wrong entry can cause bugs that are very hard
 382   // to track down - if cache entry gets invalid - we just clean it. In
 383   // this way it is always the same code path that is responsible for
 384   // updating and resolving an inline cache
 385   //
 386   // The above is no longer true. SharedRuntime::fixup_callers_callsite will change optimized
 387   // callsites. In addition ic_miss code will update a site to monomorphic if it determines
 388   // that an monomorphic call to the interpreter can now be monomorphic to compiled code.
 389   //
 390   // In both of these cases the only thing being modifed is the jump/call target and these
 391   // transitions are mt_safe
 392 
 393   Thread *thread = Thread::current();
 394   if (info.to_interpreter()) {
 395     // Call to interpreter
 396     if (info.is_optimized() && is_optimized()) {
 397        assert(is_clean(), "unsafe IC path");
 398        MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
 399       // the call analysis (callee structure) specifies that the call is optimized
 400       // (either because of CHA or the static target is final)
 401       // At code generation time, this call has been emitted as static call
 402       // Call via stub
 403       assert(info.cached_metadata() != NULL && info.cached_metadata()->is_method(), "sanity check");
 404       CompiledStaticCall* csc = compiledStaticCall_at(instruction_address());
 405       methodHandle method (thread, (Method*)info.cached_metadata());
 406       csc->set_to_interpreted(method, info.entry());
 407       if (TraceICs) {
 408          ResourceMark rm(thread);
 409          tty->print_cr ("IC@" INTPTR_FORMAT ": monomorphic to interpreter: %s",
 410            p2i(instruction_address()),
 411            method->print_value_string());
 412       }
 413     } else {
 414       // Call via method-klass-holder
 415       InlineCacheBuffer::create_transition_stub(this, info.claim_cached_icholder(), info.entry());
 416       if (TraceICs) {
 417          ResourceMark rm(thread);
 418          tty->print_cr ("IC@" INTPTR_FORMAT ": monomorphic to interpreter via icholder ", p2i(instruction_address()));
 419       }
 420     }
 421   } else {
 422     // Call to compiled code
 423     bool static_bound = info.is_optimized() || (info.cached_metadata() == NULL);
 424 #ifdef ASSERT
 425     CodeBlob* cb = CodeCache::find_blob_unsafe(info.entry());
 426     assert (cb->is_nmethod(), "must be compiled!");
 427 #endif /* ASSERT */
 428 
 429     // This is MT safe if we come from a clean-cache and go through a
 430     // non-verified entry point
 431     bool safe = SafepointSynchronize::is_at_safepoint() ||
 432                 (!is_in_transition_state() && (info.is_optimized() || static_bound || is_clean()));
 433 
 434     if (!safe) {
 435       InlineCacheBuffer::create_transition_stub(this, info.cached_metadata(), info.entry());
 436     } else {
 437       if (is_optimized()) {
 438       set_ic_destination(info.entry());
 439       } else {
 440         set_ic_destination_and_value(info.entry(), info.cached_metadata());
 441       }
 442     }
 443 
 444     if (TraceICs) {
 445       ResourceMark rm(thread);
 446       assert(info.cached_metadata() == NULL || info.cached_metadata()->is_klass(), "must be");
 447       tty->print_cr ("IC@" INTPTR_FORMAT ": monomorphic to compiled (rcvr klass) %s: %s",
 448         p2i(instruction_address()),
 449         ((Klass*)info.cached_metadata())->print_value_string(),
 450         (safe) ? "" : "via stub");
 451     }
 452   }
 453   // We can't check this anymore. With lazy deopt we could have already
 454   // cleaned this IC entry before we even return. This is possible if
 455   // we ran out of space in the inline cache buffer trying to do the
 456   // set_next and we safepointed to free up space. This is a benign
 457   // race because the IC entry was complete when we safepointed so
 458   // cleaning it immediately is harmless.
 459   // assert(is_call_to_compiled() || is_call_to_interpreted(), "sanity check");
 460 }
 461 
 462 
 463 // is_optimized: Compiler has generated an optimized call (i.e., no inline
 464 // cache) static_bound: The call can be static bound (i.e, no need to use
 465 // inline cache)
 466 void CompiledIC::compute_monomorphic_entry(methodHandle method,
 467                                            KlassHandle receiver_klass,
 468                                            bool is_optimized,
 469                                            bool static_bound,
 470                                            CompiledICInfo& info,
 471                                            TRAPS) {
 472   nmethod* method_code = method->code();
 473   address entry = NULL;
 474   if (method_code != NULL && method_code->is_in_use()) {
 475     // Call to compiled code
 476     if (static_bound || is_optimized) {
 477       entry      = method_code->verified_entry_point();
 478     } else {
 479       entry      = method_code->entry_point();
 480     }
 481   }
 482   if (entry != NULL) {
 483     // Call to compiled code
 484     info.set_compiled_entry(entry, (static_bound || is_optimized) ? NULL : receiver_klass(), is_optimized);
 485   } else {
 486     // Note: the following problem exists with Compiler1:
 487     //   - at compile time we may or may not know if the destination is final
 488     //   - if we know that the destination is final, we will emit an optimized
 489     //     virtual call (no inline cache), and need a Method* to make a call
 490     //     to the interpreter
 491     //   - if we do not know if the destination is final, we emit a standard
 492     //     virtual call, and use CompiledICHolder to call interpreted code
 493     //     (no static call stub has been generated)
 494     //     However in that case we will now notice it is static_bound
 495     //     and convert the call into what looks to be an optimized
 496     //     virtual call. This causes problems in verifying the IC because
 497     //     it look vanilla but is optimized. Code in is_call_to_interpreted
 498     //     is aware of this and weakens its asserts.
 499 
 500     // static_bound should imply is_optimized -- otherwise we have a
 501     // performance bug (statically-bindable method is called via
 502     // dynamically-dispatched call note: the reverse implication isn't
 503     // necessarily true -- the call may have been optimized based on compiler
 504     // analysis (static_bound is only based on "final" etc.)
 505 #ifdef COMPILER2
 506 #ifdef TIERED
 507 #if defined(ASSERT)
 508     // can't check the assert because we don't have the CompiledIC with which to
 509     // find the address if the call instruction.
 510     //
 511     // CodeBlob* cb = find_blob_unsafe(instruction_address());
 512     // assert(cb->is_compiled_by_c1() || !static_bound || is_optimized, "static_bound should imply is_optimized");
 513 #endif // ASSERT
 514 #else
 515     assert(!static_bound || is_optimized, "static_bound should imply is_optimized");
 516 #endif // TIERED
 517 #endif // COMPILER2
 518     if (is_optimized) {
 519       // Use stub entry
 520       info.set_interpreter_entry(method()->get_c2i_entry(), method());
 521     } else {
 522       // Use icholder entry
 523       CompiledICHolder* holder = new CompiledICHolder(method(), receiver_klass());
 524       info.set_icholder_entry(method()->get_c2i_unverified_entry(), holder);
 525     }
 526   }
 527   assert(info.is_optimized() == is_optimized, "must agree");
 528 }
 529 
 530 
 531 bool CompiledIC::is_icholder_entry(address entry) {
 532   CodeBlob* cb = CodeCache::find_blob_unsafe(entry);
 533   if (cb != NULL && cb->is_adapter_blob()) {
 534     return true;
 535   }
 536   // itable stubs also use CompiledICHolder
 537   if (cb != NULL && cb->is_vtable_blob()) {
 538     VtableStub* s = VtableStubs::entry_point(entry); 
 539     return (s != NULL) && s->is_itable_stub(); 
 540   }
 541 
 542   return false;
 543 }
 544 
 545 // ----------------------------------------------------------------------------
 546 
 547 void CompiledStaticCall::set_to_clean() {
 548   assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "mt unsafe call");
 549   // Reset call site
 550   MutexLockerEx pl(SafepointSynchronize::is_at_safepoint() ? NULL : Patching_lock, Mutex::_no_safepoint_check_flag);
 551 #ifdef ASSERT
 552   CodeBlob* cb = CodeCache::find_blob_unsafe(this);
 553   assert(cb != NULL && cb->is_nmethod(), "must be nmethod");
 554 #endif
 555   set_destination_mt_safe(SharedRuntime::get_resolve_static_call_stub());
 556 
 557   // Do not reset stub here:  It is too expensive to call find_stub.
 558   // Instead, rely on caller (nmethod::clear_inline_caches) to clear
 559   // both the call and its stub.
 560 }
 561 
 562 
 563 bool CompiledStaticCall::is_clean() const {
 564   return destination() == SharedRuntime::get_resolve_static_call_stub();
 565 }
 566 
 567 bool CompiledStaticCall::is_call_to_compiled() const {
 568   return CodeCache::contains(destination());
 569 }
 570 
 571 
 572 bool CompiledStaticCall::is_call_to_interpreted() const {
 573   // It is a call to interpreted, if it calls to a stub. Hence, the destination
 574   // must be in the stub part of the nmethod that contains the call
 575   nmethod* nm = CodeCache::find_nmethod(instruction_address());
 576   return nm->stub_contains(destination());
 577 }
 578 
 579 void CompiledStaticCall::set(const StaticCallInfo& info) {
 580   assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "mt unsafe call");
 581   MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
 582   // Updating a cache to the wrong entry can cause bugs that are very hard
 583   // to track down - if cache entry gets invalid - we just clean it. In
 584   // this way it is always the same code path that is responsible for
 585   // updating and resolving an inline cache
 586   assert(is_clean(), "do not update a call entry - use clean");
 587 
 588   if (info._to_interpreter) {
 589     // Call to interpreted code
 590     set_to_interpreted(info.callee(), info.entry());
 591   } else {
 592     if (TraceICs) {
 593       ResourceMark rm;
 594       tty->print_cr("CompiledStaticCall@" INTPTR_FORMAT ": set_to_compiled " INTPTR_FORMAT,
 595                     p2i(instruction_address()),
 596                     p2i(info.entry()));
 597     }
 598     // Call to compiled code
 599     assert (CodeCache::contains(info.entry()), "wrong entry point");
 600     set_destination_mt_safe(info.entry());
 601   }
 602 }
 603 
 604 
 605 // Compute settings for a CompiledStaticCall. Since we might have to set
 606 // the stub when calling to the interpreter, we need to return arguments.
 607 void CompiledStaticCall::compute_entry(methodHandle m, StaticCallInfo& info) {
 608   nmethod* m_code = m->code();
 609   info._callee = m;
 610   if (m_code != NULL && m_code->is_in_use()) {
 611     info._to_interpreter = false;
 612     info._entry  = m_code->verified_entry_point();
 613   } else {
 614     // Callee is interpreted code.  In any case entering the interpreter
 615     // puts a converter-frame on the stack to save arguments.
 616     assert(!m->is_method_handle_intrinsic(), "Compiled code should never call interpreter MH intrinsics");
 617     info._to_interpreter = true;
 618     info._entry      = m()->get_c2i_entry();
 619   }
 620 }
 621 
 622 address CompiledStaticCall::find_stub() {
 623   // Find reloc. information containing this call-site
 624   RelocIterator iter((nmethod*)NULL, instruction_address());
 625   while (iter.next()) {
 626     if (iter.addr() == instruction_address()) {
 627       switch(iter.type()) {
 628         case relocInfo::static_call_type:
 629           return iter.static_call_reloc()->static_stub();
 630         // We check here for opt_virtual_call_type, since we reuse the code
 631         // from the CompiledIC implementation
 632         case relocInfo::opt_virtual_call_type:
 633           return iter.opt_virtual_call_reloc()->static_stub();
 634         case relocInfo::poll_type:
 635         case relocInfo::poll_return_type: // A safepoint can't overlap a call.
 636         default:
 637           ShouldNotReachHere();
 638       }
 639     }
 640   }
 641   return NULL;
 642 }
 643 
 644 
 645 //-----------------------------------------------------------------------------
 646 // Non-product mode code
 647 #ifndef PRODUCT
 648 
 649 void CompiledIC::verify() {
 650   // make sure code pattern is actually a call imm32 instruction
 651   _ic_call->verify();
 652   if (os::is_MP()) {
 653     _ic_call->verify_alignment();
 654   }
 655   assert(is_clean() || is_call_to_compiled() || is_call_to_interpreted()
 656           || is_optimized() || is_megamorphic(), "sanity check");
 657 }
 658 
 659 void CompiledIC::print() {
 660   print_compiled_ic();
 661   tty->cr();
 662 }
 663 
 664 void CompiledIC::print_compiled_ic() {
 665   tty->print("Inline cache at " INTPTR_FORMAT ", calling %s " INTPTR_FORMAT " cached_value " INTPTR_FORMAT,
 666              p2i(instruction_address()), is_call_to_interpreted() ? "interpreted " : "", p2i(ic_destination()), p2i(is_optimized() ? NULL : cached_value()));
 667 }
 668 
 669 void CompiledStaticCall::print() {
 670   tty->print("static call at " INTPTR_FORMAT " -> ", p2i(instruction_address()));
 671   if (is_clean()) {
 672     tty->print("clean");
 673   } else if (is_call_to_compiled()) {
 674     tty->print("compiled");
 675   } else if (is_call_to_interpreted()) {
 676     tty->print("interpreted");
 677   }
 678   tty->cr();
 679 }
 680 
 681 #endif // !PRODUCT