1 /*
   2  * Copyright (c) 1997, 2016, 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 "memory/resourceArea.hpp"
  37 #include "oops/method.hpp"
  38 #include "oops/oop.inline.hpp"
  39 #include "oops/symbol.hpp"
  40 #include "runtime/icache.hpp"
  41 #include "runtime/sharedRuntime.hpp"
  42 #include "runtime/stubRoutines.hpp"
  43 #include "utilities/events.hpp"
  44 
  45 
  46 // Every time a compiled IC is changed or its type is being accessed,
  47 // either the CompiledIC_lock must be set or we must be at a safe point.
  48 
  49 //-----------------------------------------------------------------------------
  50 // Low-level access to an inline cache. Private, since they might not be
  51 // MT-safe to use.
  52 
  53 void* CompiledIC::cached_value() const {
  54   assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
  55   assert (!is_optimized(), "an optimized virtual call does not have a cached metadata");
  56 
  57   if (!is_in_transition_state()) {
  58     void* data = (void*)_value->data();
  59     // If we let the metadata value here be initialized to zero...
  60     assert(data != NULL || Universe::non_oop_word() == NULL,
  61            "no raw nulls in CompiledIC metadatas, because of patching races");
  62     return (data == (void*)Universe::non_oop_word()) ? NULL : data;
  63   } else {
  64     return InlineCacheBuffer::cached_value_for((CompiledIC *)this);
  65   }
  66 }
  67 
  68 
  69 void CompiledIC::internal_set_ic_destination(address entry_point, bool is_icstub, void* cache, bool is_icholder) {
  70   assert(entry_point != NULL, "must set legal entry point");
  71   assert(CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
  72   assert (!is_optimized() || cache == NULL, "an optimized virtual call does not have a cached metadata");
  73   assert (cache == NULL || cache != (Metadata*)badOopVal, "invalid metadata");
  74 
  75   assert(!is_icholder || is_icholder_entry(entry_point), "must be");
  76 
  77   // Don't use ic_destination for this test since that forwards
  78   // through ICBuffer instead of returning the actual current state of
  79   // the CompiledIC.
  80   if (is_icholder_entry(_ic_call->destination())) {
  81     // When patching for the ICStub case the cached value isn't
  82     // overwritten until the ICStub copied into the CompiledIC during
  83     // the next safepoint.  Make sure that the CompiledICHolder* is
  84     // marked for release at this point since it won't be identifiable
  85     // once the entry point is overwritten.
  86     InlineCacheBuffer::queue_for_release((CompiledICHolder*)_value->data());
  87   }
  88 
  89   if (TraceCompiledIC) {
  90     tty->print("  ");
  91     print_compiled_ic();
  92     tty->print(" changing destination to " INTPTR_FORMAT, p2i(entry_point));
  93     if (!is_optimized()) {
  94       tty->print(" changing cached %s to " INTPTR_FORMAT, is_icholder ? "icholder" : "metadata", p2i((address)cache));
  95     }
  96     if (is_icstub) {
  97       tty->print(" (icstub)");
  98     }
  99     tty->cr();
 100   }
 101 
 102   {
 103     MutexLockerEx pl(SafepointSynchronize::is_at_safepoint() ? NULL : Patching_lock, Mutex::_no_safepoint_check_flag);
 104 #ifdef ASSERT
 105     CodeBlob* cb = CodeCache::find_blob_unsafe(_ic_call);
 106     assert(cb != NULL && cb->is_compiled(), "must be compiled");
 107 #endif
 108      _ic_call->set_destination_mt_safe(entry_point);
 109   }
 110 
 111   if (is_optimized() || is_icstub) {
 112     // Optimized call sites don't have a cache value and ICStub call
 113     // sites only change the entry point.  Changing the value in that
 114     // case could lead to MT safety issues.
 115     assert(cache == NULL, "must be null");
 116     return;
 117   }
 118 
 119   if (cache == NULL)  cache = (void*)Universe::non_oop_word();
 120 
 121   _value->set_data((intptr_t)cache);
 122 }
 123 
 124 
 125 void CompiledIC::set_ic_destination(ICStub* stub) {
 126   internal_set_ic_destination(stub->code_begin(), true, NULL, false);
 127 }
 128 
 129 
 130 
 131 address CompiledIC::ic_destination() const {
 132  assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
 133  if (!is_in_transition_state()) {
 134    return _ic_call->destination();
 135  } else {
 136    return InlineCacheBuffer::ic_destination_for((CompiledIC *)this);
 137  }
 138 }
 139 
 140 
 141 bool CompiledIC::is_in_transition_state() const {
 142   assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
 143   return InlineCacheBuffer::contains(_ic_call->destination());
 144 }
 145 
 146 
 147 bool CompiledIC::is_icholder_call() const {
 148   assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
 149   return !_is_optimized && is_icholder_entry(ic_destination());
 150 }
 151 
 152 // Returns native address of 'call' instruction in inline-cache. Used by
 153 // the InlineCacheBuffer when it needs to find the stub.
 154 address CompiledIC::stub_address() const {
 155   assert(is_in_transition_state(), "should only be called when we are in a transition state");
 156   return _ic_call->destination();
 157 }
 158 
 159 // Clears the IC stub if the compiled IC is in transition state
 160 void CompiledIC::clear_ic_stub() {
 161   if (is_in_transition_state()) {
 162     ICStub* stub = ICStub_from_destination_address(stub_address());
 163     stub->clear();
 164   }
 165 }
 166 
 167 
 168 //-----------------------------------------------------------------------------
 169 // High-level access to an inline cache. Guaranteed to be MT-safe.
 170 
 171 void CompiledIC::initialize_from_iter(RelocIterator* iter) {
 172   assert(iter->addr() == _ic_call->instruction_address(), "must find ic_call");
 173 
 174   if (iter->type() == relocInfo::virtual_call_type) {
 175     virtual_call_Relocation* r = iter->virtual_call_reloc();
 176     _is_optimized = false;
 177     _value = nativeMovConstReg_at(r->cached_value());
 178   } else {
 179     assert(iter->type() == relocInfo::opt_virtual_call_type, "must be a virtual call");
 180     _is_optimized = true;
 181     _value = NULL;
 182   }
 183 }
 184 
 185 CompiledIC::CompiledIC(CompiledMethod* cm, NativeCall* call)
 186   : _ic_call(call)
 187 {
 188   address ic_call = _ic_call->instruction_address();
 189 
 190   assert(ic_call != NULL, "ic_call address must be set");
 191   assert(cm != NULL, "must pass compiled method");
 192   assert(cm->contains(ic_call), "must be in compiled method");
 193 
 194   // Search for the ic_call at the given address.
 195   RelocIterator iter(cm, ic_call, ic_call+1);
 196   bool ret = iter.next();
 197   assert(ret == true, "relocInfo must exist at this address");
 198   assert(iter.addr() == ic_call, "must find ic_call");
 199 
 200   initialize_from_iter(&iter);
 201 }
 202 
 203 CompiledIC::CompiledIC(RelocIterator* iter)
 204   : _ic_call(nativeCall_at(iter->addr()))
 205 {
 206   address ic_call = _ic_call->instruction_address();
 207 
 208   CompiledMethod* nm = iter->code();
 209   assert(ic_call != NULL, "ic_call address must be set");
 210   assert(nm != NULL, "must pass compiled method");
 211   assert(nm->contains(ic_call), "must be in compiled method");
 212 
 213   initialize_from_iter(iter);
 214 }
 215 
 216 bool CompiledIC::set_to_megamorphic(CallInfo* call_info, Bytecodes::Code bytecode, TRAPS) {
 217   assert(CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
 218   assert(!is_optimized(), "cannot set an optimized virtual call to megamorphic");
 219   assert(is_call_to_compiled() || is_call_to_interpreted(), "going directly to megamorphic?");
 220 
 221   address entry;
 222   if (call_info->call_kind() == CallInfo::itable_call) {
 223     assert(bytecode == Bytecodes::_invokeinterface, "");
 224     int itable_index = call_info->itable_index();
 225     entry = VtableStubs::find_itable_stub(itable_index);
 226     if (entry == false) {
 227       return false;
 228     }
 229 #ifdef ASSERT
 230     int index = call_info->resolved_method()->itable_index();
 231     assert(index == itable_index, "CallInfo pre-computes this");
 232 #endif //ASSERT
 233     InstanceKlass* k = call_info->resolved_method()->method_holder();
 234     assert(k->verify_itable_index(itable_index), "sanity check");
 235     InlineCacheBuffer::create_transition_stub(this, k, entry);
 236   } else {
 237     assert(call_info->call_kind() == CallInfo::vtable_call, "either itable or vtable");
 238     // Can be different than selected_method->vtable_index(), due to package-private etc.
 239     int vtable_index = call_info->vtable_index();
 240     assert(call_info->resolved_klass()->verify_vtable_index(vtable_index), "sanity check");
 241     entry = VtableStubs::find_vtable_stub(vtable_index);
 242     if (entry == NULL) {
 243       return false;
 244     }
 245     InlineCacheBuffer::create_transition_stub(this, NULL, entry);
 246   }
 247 
 248   if (TraceICs) {
 249     ResourceMark rm;
 250     tty->print_cr ("IC@" INTPTR_FORMAT ": to megamorphic %s entry: " INTPTR_FORMAT,
 251                    p2i(instruction_address()), call_info->selected_method()->print_value_string(), p2i(entry));
 252   }
 253 
 254   // We can't check this anymore. With lazy deopt we could have already
 255   // cleaned this IC entry before we even return. This is possible if
 256   // we ran out of space in the inline cache buffer trying to do the
 257   // set_next and we safepointed to free up space. This is a benign
 258   // race because the IC entry was complete when we safepointed so
 259   // cleaning it immediately is harmless.
 260   // assert(is_megamorphic(), "sanity check");
 261   return true;
 262 }
 263 
 264 
 265 // true if destination is megamorphic stub
 266 bool CompiledIC::is_megamorphic() const {
 267   assert(CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
 268   assert(!is_optimized(), "an optimized call cannot be megamorphic");
 269 
 270   // Cannot rely on cached_value. It is either an interface or a method.
 271   return VtableStubs::is_entry_point(ic_destination());
 272 }
 273 
 274 bool CompiledIC::is_call_to_compiled() const {
 275   assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
 276 
 277   // Use unsafe, since an inline cache might point to a zombie method. However, the zombie
 278   // method is guaranteed to still exist, since we only remove methods after all inline caches
 279   // has been cleaned up
 280   CodeBlob* cb = CodeCache::find_blob_unsafe(ic_destination());
 281   bool is_monomorphic = (cb != NULL && cb->is_compiled());
 282   // Check that the cached_value is a klass for non-optimized monomorphic calls
 283   // This assertion is invalid for compiler1: a call that does not look optimized (no static stub) can be used
 284   // for calling directly to vep without using the inline cache (i.e., cached_value == NULL).
 285   // For JVMCI this occurs because CHA is only used to improve inlining so call sites which could be optimized
 286   // virtuals because there are no currently loaded subclasses of a type are left as virtual call sites.
 287 #ifdef ASSERT
 288   CodeBlob* caller = CodeCache::find_blob_unsafe(instruction_address());
 289   bool is_c1_or_jvmci_method = caller->is_compiled_by_c1() || caller->is_compiled_by_jvmci();
 290   assert( is_c1_or_jvmci_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_compiled(), "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(const methodHandle& method,
 467                                            KlassHandle receiver_klass,
 468                                            bool is_optimized,
 469                                            bool static_bound,
 470                                            CompiledICInfo& info,
 471                                            TRAPS) {
 472   CompiledMethod* method_code = method->code();
 473 
 474   address entry = NULL;
 475   if (method_code != NULL && method_code->is_in_use()) {
 476     assert(method_code->is_compiled(), "must be compiled");
 477     // Call to compiled code
 478     if (is_optimized) {
 479       entry      = method_code->verified_entry_point();
 480     } else {
 481       entry      = method_code->entry_point();
 482     }
 483   }
 484   if (entry != NULL) {
 485     // Call to compiled code
 486     info.set_compiled_entry(entry, (static_bound || is_optimized) ? NULL : receiver_klass(), is_optimized);
 487   } else {
 488     // Note: the following problem exists with Compiler1:
 489     //   - at compile time we may or may not know if the destination is final
 490     //   - if we know that the destination is final, we will emit an optimized
 491     //     virtual call (no inline cache), and need a Method* to make a call
 492     //     to the interpreter
 493     //   - if we do not know if the destination is final, we emit a standard
 494     //     virtual call, and use CompiledICHolder to call interpreted code
 495     //     (no static call stub has been generated)
 496     //     However in that case we will now notice it is static_bound
 497     //     and convert the call into what looks to be an optimized
 498     //     virtual call. This causes problems in verifying the IC because
 499     //     it look vanilla but is optimized. Code in is_call_to_interpreted
 500     //     is aware of this and weakens its asserts.
 501 
 502     // static_bound should imply is_optimized -- otherwise we have a
 503     // performance bug (statically-bindable method is called via
 504     // dynamically-dispatched call note: the reverse implication isn't
 505     // necessarily true -- the call may have been optimized based on compiler
 506     // analysis (static_bound is only based on "final" etc.)
 507 #ifdef COMPILER2
 508 #ifdef TIERED
 509 #if defined(ASSERT)
 510     // can't check the assert because we don't have the CompiledIC with which to
 511     // find the address if the call instruction.
 512     //
 513     // CodeBlob* cb = find_blob_unsafe(instruction_address());
 514     // assert(cb->is_compiled_by_c1() || !static_bound || is_optimized, "static_bound should imply is_optimized");
 515 #endif // ASSERT
 516 #else
 517     assert(!static_bound || is_optimized, "static_bound should imply is_optimized");
 518 #endif // TIERED
 519 #endif // COMPILER2
 520     if (is_optimized) {
 521       // Use stub entry
 522       info.set_interpreter_entry(method()->get_c2i_entry(), method());
 523     } else {
 524       // Use icholder entry
 525       assert(method_code == NULL || method_code->is_compiled(), "must be compiled");
 526       CompiledICHolder* holder = new CompiledICHolder(method(), receiver_klass());
 527       info.set_icholder_entry(method()->get_c2i_unverified_entry(), holder);
 528     }
 529   }
 530   assert(info.is_optimized() == is_optimized, "must agree");
 531 }
 532 
 533 
 534 bool CompiledIC::is_icholder_entry(address entry) {
 535   CodeBlob* cb = CodeCache::find_blob_unsafe(entry);
 536   return (cb != NULL && cb->is_adapter_blob());
 537 }
 538 
 539 // Release the CompiledICHolder* associated with this call site is there is one.
 540 void CompiledIC::cleanup_call_site(virtual_call_Relocation* call_site) {
 541   // This call site might have become stale so inspect it carefully.
 542   NativeCall* call = nativeCall_at(call_site->addr());
 543   if (is_icholder_entry(call->destination())) {
 544     NativeMovConstReg* value = nativeMovConstReg_at(call_site->cached_value());
 545     InlineCacheBuffer::queue_for_release((CompiledICHolder*)value->data());
 546   }
 547 }
 548 
 549 bool CompiledIC::is_icholder_call_site(virtual_call_Relocation* call_site) {
 550   // This call site might have become stale so inspect it carefully.
 551   NativeCall* call = nativeCall_at(call_site->addr());
 552   return is_icholder_entry(call->destination());
 553 }
 554 
 555 // ----------------------------------------------------------------------------
 556 
 557 void CompiledStaticCall::set_to_clean() {
 558   assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "mt unsafe call");
 559   // Reset call site
 560   MutexLockerEx pl(SafepointSynchronize::is_at_safepoint() ? NULL : Patching_lock, Mutex::_no_safepoint_check_flag);
 561 #ifdef ASSERT
 562   CodeBlob* cb = CodeCache::find_blob_unsafe(this);
 563   assert(cb != NULL && cb->is_compiled(), "must be compiled");
 564 #endif
 565   set_destination_mt_safe(SharedRuntime::get_resolve_static_call_stub());
 566 
 567   // Do not reset stub here:  It is too expensive to call find_stub.
 568   // Instead, rely on caller (nmethod::clear_inline_caches) to clear
 569   // both the call and its stub.
 570 }
 571 
 572 
 573 bool CompiledStaticCall::is_clean() const {
 574   return destination() == SharedRuntime::get_resolve_static_call_stub();
 575 }
 576 
 577 bool CompiledStaticCall::is_call_to_compiled() const {
 578   return CodeCache::contains(destination());
 579 }
 580 
 581 
 582 bool CompiledStaticCall::is_call_to_interpreted() const {
 583   // It is a call to interpreted, if it calls to a stub. Hence, the destination
 584   // must be in the stub part of the nmethod that contains the call
 585   CompiledMethod* cm = CodeCache::find_compiled(instruction_address());
 586   return cm->stub_contains(destination());
 587 }
 588 
 589 void CompiledStaticCall::set(const StaticCallInfo& info) {
 590   assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "mt unsafe call");
 591   MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
 592   // Updating a cache to the wrong entry can cause bugs that are very hard
 593   // to track down - if cache entry gets invalid - we just clean it. In
 594   // this way it is always the same code path that is responsible for
 595   // updating and resolving an inline cache
 596   assert(is_clean(), "do not update a call entry - use clean");
 597 
 598   if (info._to_interpreter) {
 599     // Call to interpreted code
 600     set_to_interpreted(info.callee(), info.entry());
 601   } else {
 602     if (TraceICs) {
 603       ResourceMark rm;
 604       tty->print_cr("CompiledStaticCall@" INTPTR_FORMAT ": set_to_compiled " INTPTR_FORMAT,
 605                     p2i(instruction_address()),
 606                     p2i(info.entry()));
 607     }
 608     // Call to compiled code
 609     assert (CodeCache::contains(info.entry()), "wrong entry point");
 610     set_destination_mt_safe(info.entry());
 611   }
 612 }
 613 
 614 
 615 // Compute settings for a CompiledStaticCall. Since we might have to set
 616 // the stub when calling to the interpreter, we need to return arguments.
 617 void CompiledStaticCall::compute_entry(const methodHandle& m, StaticCallInfo& info) {
 618   CompiledMethod* m_code = m->code();
 619   info._callee = m;
 620   if (m_code != NULL && m_code->is_in_use()) {
 621     info._to_interpreter = false;
 622     info._entry  = m_code->verified_entry_point();
 623   } else {
 624     // Callee is interpreted code.  In any case entering the interpreter
 625     // puts a converter-frame on the stack to save arguments.
 626     assert(!m->is_method_handle_intrinsic(), "Compiled code should never call interpreter MH intrinsics");
 627     info._to_interpreter = true;
 628     info._entry      = m()->get_c2i_entry();
 629   }
 630 }
 631 
 632 address CompiledStaticCall::find_stub() {
 633   // Find reloc. information containing this call-site
 634   RelocIterator iter((nmethod*)NULL, instruction_address());
 635   while (iter.next()) {
 636     if (iter.addr() == instruction_address()) {
 637       switch(iter.type()) {
 638         case relocInfo::static_call_type:
 639           return iter.static_call_reloc()->static_stub();
 640         // We check here for opt_virtual_call_type, since we reuse the code
 641         // from the CompiledIC implementation
 642         case relocInfo::opt_virtual_call_type:
 643           return iter.opt_virtual_call_reloc()->static_stub();
 644         case relocInfo::poll_type:
 645         case relocInfo::poll_return_type: // A safepoint can't overlap a call.
 646         default:
 647           ShouldNotReachHere();
 648       }
 649     }
 650   }
 651   return NULL;
 652 }
 653 
 654 
 655 //-----------------------------------------------------------------------------
 656 // Non-product mode code
 657 #ifndef PRODUCT
 658 
 659 void CompiledIC::verify() {
 660   // make sure code pattern is actually a call imm32 instruction
 661   _ic_call->verify();
 662   if (os::is_MP()) {
 663     _ic_call->verify_alignment();
 664   }
 665   assert(is_clean() || is_call_to_compiled() || is_call_to_interpreted()
 666           || is_optimized() || is_megamorphic(), "sanity check");
 667 }
 668 
 669 void CompiledIC::print() {
 670   print_compiled_ic();
 671   tty->cr();
 672 }
 673 
 674 void CompiledIC::print_compiled_ic() {
 675   tty->print("Inline cache at " INTPTR_FORMAT ", calling %s " INTPTR_FORMAT " cached_value " INTPTR_FORMAT,
 676              p2i(instruction_address()), is_call_to_interpreted() ? "interpreted " : "", p2i(ic_destination()), p2i(is_optimized() ? NULL : cached_value()));
 677 }
 678 
 679 void CompiledStaticCall::print() {
 680   tty->print("static call at " INTPTR_FORMAT " -> ", p2i(instruction_address()));
 681   if (is_clean()) {
 682     tty->print("clean");
 683   } else if (is_call_to_compiled()) {
 684     tty->print("compiled");
 685   } else if (is_call_to_interpreted()) {
 686     tty->print("interpreted");
 687   }
 688   tty->cr();
 689 }
 690 
 691 #endif // !PRODUCT