compiledIC.cpp revision 9248:6ab7e19c9220
1/*
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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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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
52void* 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
68void 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
124void CompiledIC::set_ic_destination(ICStub* stub) {
125  internal_set_ic_destination(stub->code_begin(), true, NULL, false);
126}
127
128
129
130address 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
140bool 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
146bool 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.
153address 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
159void 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
170void 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
184CompiledIC::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
202CompiledIC::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
215bool 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#endif //ASSERT
232    InstanceKlass* k = call_info->resolved_method()->method_holder();
233    assert(k->verify_itable_index(itable_index), "sanity check");
234    InlineCacheBuffer::create_transition_stub(this, k, entry);
235  } else {
236    assert(call_info->call_kind() == CallInfo::vtable_call, "either itable or vtable");
237    // Can be different than selected_method->vtable_index(), due to package-private etc.
238    int vtable_index = call_info->vtable_index();
239    assert(call_info->resolved_klass()->verify_vtable_index(vtable_index), "sanity check");
240    entry = VtableStubs::find_vtable_stub(vtable_index);
241    if (entry == NULL) {
242      return false;
243    }
244    InlineCacheBuffer::create_transition_stub(this, NULL, entry);
245  }
246
247  if (TraceICs) {
248    ResourceMark rm;
249    tty->print_cr ("IC@" INTPTR_FORMAT ": to megamorphic %s entry: " INTPTR_FORMAT,
250                   p2i(instruction_address()), call_info->selected_method()->print_value_string(), p2i(entry));
251  }
252
253  // We can't check this anymore. With lazy deopt we could have already
254  // cleaned this IC entry before we even return. This is possible if
255  // we ran out of space in the inline cache buffer trying to do the
256  // set_next and we safepointed to free up space. This is a benign
257  // race because the IC entry was complete when we safepointed so
258  // cleaning it immediately is harmless.
259  // assert(is_megamorphic(), "sanity check");
260  return true;
261}
262
263
264// true if destination is megamorphic stub
265bool CompiledIC::is_megamorphic() const {
266  assert(CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
267  assert(!is_optimized(), "an optimized call cannot be megamorphic");
268
269  // Cannot rely on cached_value. It is either an interface or a method.
270  return VtableStubs::is_entry_point(ic_destination());
271}
272
273bool CompiledIC::is_call_to_compiled() const {
274  assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
275
276  // Use unsafe, since an inline cache might point to a zombie method. However, the zombie
277  // method is guaranteed to still exist, since we only remove methods after all inline caches
278  // has been cleaned up
279  CodeBlob* cb = CodeCache::find_blob_unsafe(ic_destination());
280  bool is_monomorphic = (cb != NULL && cb->is_nmethod());
281  // Check that the cached_value is a klass for non-optimized monomorphic calls
282  // This assertion is invalid for compiler1: a call that does not look optimized (no static stub) can be used
283  // for calling directly to vep without using the inline cache (i.e., cached_value == NULL).
284  // For JVMCI this occurs because CHA is only used to improve inlining so call sites which could be optimized
285  // virtuals because there are no currently loaded subclasses of a type are left as virtual call sites.
286#ifdef ASSERT
287  CodeBlob* caller = CodeCache::find_blob_unsafe(instruction_address());
288  bool is_c1_or_jvmci_method = caller->is_compiled_by_c1() || caller->is_compiled_by_jvmci();
289  assert( is_c1_or_jvmci_method ||
290         !is_monomorphic ||
291         is_optimized() ||
292         !caller->is_alive() ||
293         (cached_metadata() != NULL && cached_metadata()->is_klass()), "sanity check");
294#endif // ASSERT
295  return is_monomorphic;
296}
297
298
299bool CompiledIC::is_call_to_interpreted() const {
300  assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
301  // Call to interpreter if destination is either calling to a stub (if it
302  // is optimized), or calling to an I2C blob
303  bool is_call_to_interpreted = false;
304  if (!is_optimized()) {
305    // must use unsafe because the destination can be a zombie (and we're cleaning)
306    // and the print_compiled_ic code wants to know if site (in the non-zombie)
307    // is to the interpreter.
308    CodeBlob* cb = CodeCache::find_blob_unsafe(ic_destination());
309    is_call_to_interpreted = (cb != NULL && cb->is_adapter_blob());
310    assert(!is_call_to_interpreted || (is_icholder_call() && cached_icholder() != NULL), "sanity check");
311  } else {
312    // Check if we are calling into our own codeblob (i.e., to a stub)
313    CodeBlob* cb = CodeCache::find_blob(_ic_call->instruction_address());
314    address dest = ic_destination();
315#ifdef ASSERT
316    {
317      CodeBlob* db = CodeCache::find_blob_unsafe(dest);
318      assert(!db->is_adapter_blob(), "must use stub!");
319    }
320#endif /* ASSERT */
321    is_call_to_interpreted = cb->contains(dest);
322  }
323  return is_call_to_interpreted;
324}
325
326
327void CompiledIC::set_to_clean(bool in_use) {
328  assert(SafepointSynchronize::is_at_safepoint() || CompiledIC_lock->is_locked() , "MT-unsafe call");
329  if (TraceInlineCacheClearing || TraceICs) {
330    tty->print_cr("IC@" INTPTR_FORMAT ": set to clean", p2i(instruction_address()));
331    print();
332  }
333
334  address entry;
335  if (is_optimized()) {
336    entry = SharedRuntime::get_resolve_opt_virtual_call_stub();
337  } else {
338    entry = SharedRuntime::get_resolve_virtual_call_stub();
339  }
340
341  // A zombie transition will always be safe, since the metadata has already been set to NULL, so
342  // we only need to patch the destination
343  bool safe_transition = !in_use || is_optimized() || SafepointSynchronize::is_at_safepoint();
344
345  if (safe_transition) {
346    // Kill any leftover stub we might have too
347    clear_ic_stub();
348    if (is_optimized()) {
349      set_ic_destination(entry);
350    } else {
351      set_ic_destination_and_value(entry, (void*)NULL);
352    }
353  } else {
354    // Unsafe transition - create stub.
355    InlineCacheBuffer::create_transition_stub(this, NULL, entry);
356  }
357  // We can't check this anymore. With lazy deopt we could have already
358  // cleaned this IC entry before we even return. This is possible if
359  // we ran out of space in the inline cache buffer trying to do the
360  // set_next and we safepointed to free up space. This is a benign
361  // race because the IC entry was complete when we safepointed so
362  // cleaning it immediately is harmless.
363  // assert(is_clean(), "sanity check");
364}
365
366
367bool CompiledIC::is_clean() const {
368  assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
369  bool is_clean = false;
370  address dest = ic_destination();
371  is_clean = dest == SharedRuntime::get_resolve_opt_virtual_call_stub() ||
372             dest == SharedRuntime::get_resolve_virtual_call_stub();
373  assert(!is_clean || is_optimized() || cached_value() == NULL, "sanity check");
374  return is_clean;
375}
376
377
378void CompiledIC::set_to_monomorphic(CompiledICInfo& info) {
379  assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
380  // Updating a cache to the wrong entry can cause bugs that are very hard
381  // to track down - if cache entry gets invalid - we just clean it. In
382  // this way it is always the same code path that is responsible for
383  // updating and resolving an inline cache
384  //
385  // The above is no longer true. SharedRuntime::fixup_callers_callsite will change optimized
386  // callsites. In addition ic_miss code will update a site to monomorphic if it determines
387  // that an monomorphic call to the interpreter can now be monomorphic to compiled code.
388  //
389  // In both of these cases the only thing being modifed is the jump/call target and these
390  // transitions are mt_safe
391
392  Thread *thread = Thread::current();
393  if (info.to_interpreter()) {
394    // Call to interpreter
395    if (info.is_optimized() && is_optimized()) {
396       assert(is_clean(), "unsafe IC path");
397       MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
398      // the call analysis (callee structure) specifies that the call is optimized
399      // (either because of CHA or the static target is final)
400      // At code generation time, this call has been emitted as static call
401      // Call via stub
402      assert(info.cached_metadata() != NULL && info.cached_metadata()->is_method(), "sanity check");
403      CompiledStaticCall* csc = compiledStaticCall_at(instruction_address());
404      methodHandle method (thread, (Method*)info.cached_metadata());
405      csc->set_to_interpreted(method, info.entry());
406      if (TraceICs) {
407         ResourceMark rm(thread);
408         tty->print_cr ("IC@" INTPTR_FORMAT ": monomorphic to interpreter: %s",
409           p2i(instruction_address()),
410           method->print_value_string());
411      }
412    } else {
413      // Call via method-klass-holder
414      InlineCacheBuffer::create_transition_stub(this, info.claim_cached_icholder(), info.entry());
415      if (TraceICs) {
416         ResourceMark rm(thread);
417         tty->print_cr ("IC@" INTPTR_FORMAT ": monomorphic to interpreter via icholder ", p2i(instruction_address()));
418      }
419    }
420  } else {
421    // Call to compiled code
422    bool static_bound = info.is_optimized() || (info.cached_metadata() == NULL);
423#ifdef ASSERT
424    CodeBlob* cb = CodeCache::find_blob_unsafe(info.entry());
425    assert (cb->is_nmethod(), "must be compiled!");
426#endif /* ASSERT */
427
428    // This is MT safe if we come from a clean-cache and go through a
429    // non-verified entry point
430    bool safe = SafepointSynchronize::is_at_safepoint() ||
431                (!is_in_transition_state() && (info.is_optimized() || static_bound || is_clean()));
432
433    if (!safe) {
434      InlineCacheBuffer::create_transition_stub(this, info.cached_metadata(), info.entry());
435    } else {
436      if (is_optimized()) {
437      set_ic_destination(info.entry());
438      } else {
439        set_ic_destination_and_value(info.entry(), info.cached_metadata());
440      }
441    }
442
443    if (TraceICs) {
444      ResourceMark rm(thread);
445      assert(info.cached_metadata() == NULL || info.cached_metadata()->is_klass(), "must be");
446      tty->print_cr ("IC@" INTPTR_FORMAT ": monomorphic to compiled (rcvr klass) %s: %s",
447        p2i(instruction_address()),
448        ((Klass*)info.cached_metadata())->print_value_string(),
449        (safe) ? "" : "via stub");
450    }
451  }
452  // We can't check this anymore. With lazy deopt we could have already
453  // cleaned this IC entry before we even return. This is possible if
454  // we ran out of space in the inline cache buffer trying to do the
455  // set_next and we safepointed to free up space. This is a benign
456  // race because the IC entry was complete when we safepointed so
457  // cleaning it immediately is harmless.
458  // assert(is_call_to_compiled() || is_call_to_interpreted(), "sanity check");
459}
460
461
462// is_optimized: Compiler has generated an optimized call (i.e., no inline
463// cache) static_bound: The call can be static bound (i.e, no need to use
464// inline cache)
465void CompiledIC::compute_monomorphic_entry(const methodHandle& method,
466                                           KlassHandle receiver_klass,
467                                           bool is_optimized,
468                                           bool static_bound,
469                                           CompiledICInfo& info,
470                                           TRAPS) {
471  nmethod* method_code = method->code();
472  address entry = NULL;
473  if (method_code != NULL && method_code->is_in_use()) {
474    // Call to compiled code
475    if (static_bound || is_optimized) {
476      entry      = method_code->verified_entry_point();
477    } else {
478      entry      = method_code->entry_point();
479    }
480  }
481  if (entry != NULL) {
482    // Call to compiled code
483    info.set_compiled_entry(entry, (static_bound || is_optimized) ? NULL : receiver_klass(), is_optimized);
484  } else {
485    // Note: the following problem exists with Compiler1:
486    //   - at compile time we may or may not know if the destination is final
487    //   - if we know that the destination is final, we will emit an optimized
488    //     virtual call (no inline cache), and need a Method* to make a call
489    //     to the interpreter
490    //   - if we do not know if the destination is final, we emit a standard
491    //     virtual call, and use CompiledICHolder to call interpreted code
492    //     (no static call stub has been generated)
493    //     However in that case we will now notice it is static_bound
494    //     and convert the call into what looks to be an optimized
495    //     virtual call. This causes problems in verifying the IC because
496    //     it look vanilla but is optimized. Code in is_call_to_interpreted
497    //     is aware of this and weakens its asserts.
498
499    // static_bound should imply is_optimized -- otherwise we have a
500    // performance bug (statically-bindable method is called via
501    // dynamically-dispatched call note: the reverse implication isn't
502    // necessarily true -- the call may have been optimized based on compiler
503    // analysis (static_bound is only based on "final" etc.)
504#ifdef COMPILER2
505#ifdef TIERED
506#if defined(ASSERT)
507    // can't check the assert because we don't have the CompiledIC with which to
508    // find the address if the call instruction.
509    //
510    // CodeBlob* cb = find_blob_unsafe(instruction_address());
511    // assert(cb->is_compiled_by_c1() || !static_bound || is_optimized, "static_bound should imply is_optimized");
512#endif // ASSERT
513#else
514    assert(!static_bound || is_optimized, "static_bound should imply is_optimized");
515#endif // TIERED
516#endif // COMPILER2
517    if (is_optimized) {
518      // Use stub entry
519      info.set_interpreter_entry(method()->get_c2i_entry(), method());
520    } else {
521      // Use icholder entry
522      CompiledICHolder* holder = new CompiledICHolder(method(), receiver_klass());
523      info.set_icholder_entry(method()->get_c2i_unverified_entry(), holder);
524    }
525  }
526  assert(info.is_optimized() == is_optimized, "must agree");
527}
528
529
530bool CompiledIC::is_icholder_entry(address entry) {
531  CodeBlob* cb = CodeCache::find_blob_unsafe(entry);
532  return (cb != NULL && cb->is_adapter_blob());
533}
534
535// ----------------------------------------------------------------------------
536
537void CompiledStaticCall::set_to_clean() {
538  assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "mt unsafe call");
539  // Reset call site
540  MutexLockerEx pl(SafepointSynchronize::is_at_safepoint() ? NULL : Patching_lock, Mutex::_no_safepoint_check_flag);
541#ifdef ASSERT
542  CodeBlob* cb = CodeCache::find_blob_unsafe(this);
543  assert(cb != NULL && cb->is_nmethod(), "must be nmethod");
544#endif
545  set_destination_mt_safe(SharedRuntime::get_resolve_static_call_stub());
546
547  // Do not reset stub here:  It is too expensive to call find_stub.
548  // Instead, rely on caller (nmethod::clear_inline_caches) to clear
549  // both the call and its stub.
550}
551
552
553bool CompiledStaticCall::is_clean() const {
554  return destination() == SharedRuntime::get_resolve_static_call_stub();
555}
556
557bool CompiledStaticCall::is_call_to_compiled() const {
558  return CodeCache::contains(destination());
559}
560
561
562bool CompiledStaticCall::is_call_to_interpreted() const {
563  // It is a call to interpreted, if it calls to a stub. Hence, the destination
564  // must be in the stub part of the nmethod that contains the call
565  nmethod* nm = CodeCache::find_nmethod(instruction_address());
566  return nm->stub_contains(destination());
567}
568
569void CompiledStaticCall::set(const StaticCallInfo& info) {
570  assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "mt unsafe call");
571  MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
572  // Updating a cache to the wrong entry can cause bugs that are very hard
573  // to track down - if cache entry gets invalid - we just clean it. In
574  // this way it is always the same code path that is responsible for
575  // updating and resolving an inline cache
576  assert(is_clean(), "do not update a call entry - use clean");
577
578  if (info._to_interpreter) {
579    // Call to interpreted code
580    set_to_interpreted(info.callee(), info.entry());
581  } else {
582    if (TraceICs) {
583      ResourceMark rm;
584      tty->print_cr("CompiledStaticCall@" INTPTR_FORMAT ": set_to_compiled " INTPTR_FORMAT,
585                    p2i(instruction_address()),
586                    p2i(info.entry()));
587    }
588    // Call to compiled code
589    assert (CodeCache::contains(info.entry()), "wrong entry point");
590    set_destination_mt_safe(info.entry());
591  }
592}
593
594
595// Compute settings for a CompiledStaticCall. Since we might have to set
596// the stub when calling to the interpreter, we need to return arguments.
597void CompiledStaticCall::compute_entry(const methodHandle& m, StaticCallInfo& info) {
598  nmethod* m_code = m->code();
599  info._callee = m;
600  if (m_code != NULL && m_code->is_in_use()) {
601    info._to_interpreter = false;
602    info._entry  = m_code->verified_entry_point();
603  } else {
604    // Callee is interpreted code.  In any case entering the interpreter
605    // puts a converter-frame on the stack to save arguments.
606    assert(!m->is_method_handle_intrinsic(), "Compiled code should never call interpreter MH intrinsics");
607    info._to_interpreter = true;
608    info._entry      = m()->get_c2i_entry();
609  }
610}
611
612address CompiledStaticCall::find_stub() {
613  // Find reloc. information containing this call-site
614  RelocIterator iter((nmethod*)NULL, instruction_address());
615  while (iter.next()) {
616    if (iter.addr() == instruction_address()) {
617      switch(iter.type()) {
618        case relocInfo::static_call_type:
619          return iter.static_call_reloc()->static_stub();
620        // We check here for opt_virtual_call_type, since we reuse the code
621        // from the CompiledIC implementation
622        case relocInfo::opt_virtual_call_type:
623          return iter.opt_virtual_call_reloc()->static_stub();
624        case relocInfo::poll_type:
625        case relocInfo::poll_return_type: // A safepoint can't overlap a call.
626        default:
627          ShouldNotReachHere();
628      }
629    }
630  }
631  return NULL;
632}
633
634
635//-----------------------------------------------------------------------------
636// Non-product mode code
637#ifndef PRODUCT
638
639void CompiledIC::verify() {
640  // make sure code pattern is actually a call imm32 instruction
641  _ic_call->verify();
642  if (os::is_MP()) {
643    _ic_call->verify_alignment();
644  }
645  assert(is_clean() || is_call_to_compiled() || is_call_to_interpreted()
646          || is_optimized() || is_megamorphic(), "sanity check");
647}
648
649void CompiledIC::print() {
650  print_compiled_ic();
651  tty->cr();
652}
653
654void CompiledIC::print_compiled_ic() {
655  tty->print("Inline cache at " INTPTR_FORMAT ", calling %s " INTPTR_FORMAT " cached_value " INTPTR_FORMAT,
656             p2i(instruction_address()), is_call_to_interpreted() ? "interpreted " : "", p2i(ic_destination()), p2i(is_optimized() ? NULL : cached_value()));
657}
658
659void CompiledStaticCall::print() {
660  tty->print("static call at " INTPTR_FORMAT " -> ", p2i(instruction_address()));
661  if (is_clean()) {
662    tty->print("clean");
663  } else if (is_call_to_compiled()) {
664    tty->print("compiled");
665  } else if (is_call_to_interpreted()) {
666    tty->print("interpreted");
667  }
668  tty->cr();
669}
670
671#endif // !PRODUCT
672