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