C++ p2i函数代码示例

void ThreadLocalAllocBuffer::resize() {
  // Compute the next tlab size using expected allocation amount
  assert(ResizeTLAB, "Should not call this otherwise");
  size_t alloc = (size_t)(_allocation_fraction.average() *
                          (Universe::heap()->tlab_capacity(myThread()) / HeapWordSize));
  size_t new_size = alloc / _target_refills;

  new_size = MIN2(MAX2(new_size, min_size()), max_size());

  size_t aligned_new_size = align_object_size(new_size);

  if (PrintTLAB && Verbose) {
    gclog_or_tty->print("TLAB new size: thread: " INTPTR_FORMAT " [id: %2d]"
                        " refills %d  alloc: %8.6f desired_size: " SIZE_FORMAT " -> " SIZE_FORMAT "\n",
                        p2i(myThread()), myThread()->osthread()->thread_id(),
                        _target_refills, _allocation_fraction.average(), desired_size(), aligned_new_size);
  }
  set_desired_size(aligned_new_size);
  set_refill_waste_limit(initial_refill_waste_limit());
}

 // The rate estimate is in blocks per second.
 void compute_desired(size_t count,
                      float inter_sweep_current,
                      float inter_sweep_estimate,
                      float intra_sweep_estimate) {
   // If the latest inter-sweep time is below our granularity
   // of measurement, we may call in here with
   // inter_sweep_current == 0. However, even for suitably small
   // but non-zero inter-sweep durations, we may not trust the accuracy
   // of accumulated data, since it has not been "integrated"
   // (read "low-pass-filtered") long enough, and would be
   // vulnerable to noisy glitches. In such cases, we
   // ignore the current sample and use currently available
   // historical estimates.
   assert(prev_sweep() + split_births() + coal_births()        // "Total Production Stock"
          >= split_deaths() + coal_deaths() + (ssize_t)count, // "Current stock + depletion"
          "Conservation Principle");
   if (inter_sweep_current > _threshold) {
     ssize_t demand = prev_sweep() - (ssize_t)count + split_births() + coal_births()
                      - split_deaths() - coal_deaths();
     assert(demand >= 0,
            err_msg("Demand (" SSIZE_FORMAT ") should be non-negative for "
                    PTR_FORMAT " (size=" SIZE_FORMAT ")",
                    demand, p2i(this), count));
     // Defensive: adjust for imprecision in event counting
     if (demand < 0) {
       demand = 0;
     }
     float old_rate = _demand_rate_estimate.padded_average();
     float rate = ((float)demand)/inter_sweep_current;
     _demand_rate_estimate.sample(rate);
     float new_rate = _demand_rate_estimate.padded_average();
     ssize_t old_desired = _desired;
     float delta_ise = (CMSExtrapolateSweep ? intra_sweep_estimate : 0.0);
     _desired = (ssize_t)(new_rate * (inter_sweep_estimate + delta_ise));
     if (PrintFLSStatistics > 1) {
       gclog_or_tty->print_cr("demand: " SSIZE_FORMAT ", old_rate: %f, current_rate: %f, "
                              "new_rate: %f, old_desired: " SSIZE_FORMAT ", new_desired: " SSIZE_FORMAT,
                               demand, old_rate, rate, new_rate, old_desired, _desired);
     }
   }
 }

// Walk the next batch of stack frames
//
// Parameters:
//   stackStream    StackStream object
//   mode           Stack walking mode.
//   magic          Must be valid value to continue the stack walk
//   frame_count    Number of frames to be decoded.
//   start_index    Start index to the user-supplied buffers.
//   frames_array   Buffer to store StackFrame in, starting at start_index.
//
// Returns the end index of frame filled in the buffer.
//
jint StackWalk::moreFrames(Handle stackStream, jlong mode, jlong magic,
                           int frame_count, int start_index,
                           objArrayHandle frames_array,
                           TRAPS)
{
  JavaThread* jt = (JavaThread*)THREAD;
  JavaFrameStream* existing_stream = JavaFrameStream::from_current(jt, magic, frames_array);
  if (existing_stream == NULL) {
    THROW_MSG_(vmSymbols::java_lang_InternalError(), "doStackWalk: corrupted buffers", 0L);
  }

  if (frames_array.is_null()) {
    THROW_MSG_(vmSymbols::java_lang_NullPointerException(), "frames_array is NULL", 0L);
  }

  if (TraceStackWalk) {
    tty->print_cr("StackWalk::moreFrames frame_count %d existing_stream " PTR_FORMAT " start %d frames %d",
                  frame_count, p2i(existing_stream), start_index, frames_array->length());
  }
  int end_index = start_index;
  if (frame_count <= 0) {
    return end_index;        // No operation.
  }

  int count = frame_count + start_index;
  assert (frames_array->length() >= count, "not enough space in buffers");

  JavaFrameStream& stream = (*existing_stream);
  if (!stream.at_end()) {
    stream.next(); // advance past the last frame decoded in previous batch
    if (!stream.at_end()) {
      int n = fill_in_frames(mode, stream, frame_count, start_index,
                             frames_array, end_index, CHECK_0);
      if (n < 1) {
        THROW_MSG_(vmSymbols::java_lang_InternalError(), "doStackWalk: later decode failed", 0L);
      }
      return end_index;
    }
  }
  return end_index;
}

size_t ContiguousSpace::block_size(const HeapWord* p) const {
  assert(MemRegion(bottom(), end()).contains(p),
         "p (" PTR_FORMAT ") not in space [" PTR_FORMAT ", " PTR_FORMAT ")",
         p2i(p), p2i(bottom()), p2i(end()));
  HeapWord* current_top = top();
  assert(p <= current_top,
         "p > current top - p: " PTR_FORMAT ", current top: " PTR_FORMAT,
         p2i(p), p2i(current_top));
  assert(p == current_top || oop(p)->is_oop(),
         "p (" PTR_FORMAT ") is not a block start - "
         "current_top: " PTR_FORMAT ", is_oop: %s",
         p2i(p), p2i(current_top), BOOL_TO_STR(oop(p)->is_oop()));
  if (p < current_top) {
    return oop(p)->size();
  } else {
    assert(p == current_top, "just checking");
    return pointer_delta(end(), (HeapWord*) p);
  }
}

void HeapRegionManager::verify() {
  guarantee(length() <= _allocated_heapregions_length,
            "invariant: _length: %u _allocated_length: %u",
            length(), _allocated_heapregions_length);
  guarantee(_allocated_heapregions_length <= max_length(),
            "invariant: _allocated_length: %u _max_length: %u",
            _allocated_heapregions_length, max_length());

  bool prev_committed = true;
  uint num_committed = 0;
  HeapWord* prev_end = heap_bottom();
  for (uint i = 0; i < _allocated_heapregions_length; i++) {
    if (!is_available(i)) {
      prev_committed = false;
      continue;
    }
    num_committed++;
    HeapRegion* hr = _regions.get_by_index(i);
    guarantee(hr != NULL, "invariant: i: %u", i);
    guarantee(!prev_committed || hr->bottom() == prev_end,
              "invariant i: %u " HR_FORMAT " prev_end: " PTR_FORMAT,
              i, HR_FORMAT_PARAMS(hr), p2i(prev_end));
    guarantee(hr->hrm_index() == i,
              "invariant: i: %u hrm_index(): %u", i, hr->hrm_index());
    // Asserts will fire if i is >= _length
    HeapWord* addr = hr->bottom();
    guarantee(addr_to_region(addr) == hr, "sanity");
    // We cannot check whether the region is part of a particular set: at the time
    // this method may be called, we have only completed allocation of the regions,
    // but not put into a region set.
    prev_committed = true;
    prev_end = hr->end();
  }
  for (uint i = _allocated_heapregions_length; i < max_length(); i++) {
    guarantee(_regions.get_by_index(i) == NULL, "invariant i: %u", i);
  }

  guarantee(num_committed == _num_committed, "Found %u committed regions, but should be %u", num_committed, _num_committed);
  _free_list.verify();
}

int fcloseTIMEOUT_FL(FL_PAR,FILE *fp)
{	int rcode;

	if( fileno(fp) < 0 ){
		porting_dbg("+++EPIPE[%d] fcloseTIMEOUT() for EOF",fileno(fp));
		/*
		return EOF;
		9.8.2 should free the FILE structure.
		*/
		rcode = fcloseFILE(fp);
		return rcode;
	}

	/*
	 * 9.8.2 this code is bad leaving FILE and descriptor unclosed.
	 * added in 2.4.8 maybe (?) intented to close disconnected stream
	 * without causing alarm signal for timeout (and buffer flushing ?).
	if( feof(fp) )
		return EOF;
	 */
	if( feof(fp) /*|| ferror(fp)*/ ){
		if( ferror(fp) || LOG_VERBOSE )
		sv1log("-- fcloseTIMEOUT(%X/%d/S%d) EOF=%d ERR=%d\n",
			p2i(fp),fileno(fp),SocketOf(fileno(fp)),feof(fp),ferror(fp));
		dupclosed_FL(FL_BAR,fileno(fp));
		rcode = Xfclose(FL_BAR,fp);
		return rcode;
	}

	{
	fRETURN_ONTIMEOUTX(fp,-1,EOF,LIN_TIMEOUT+2);
	/*
	rcode = fclose(fp);
	*/
	rcode = Xfclose(FL_BAR,fp);
	DONE_SUCCESSFULLY();
	return rcode;
	}
}

inline void vframeStreamCommon::fill_from_compiled_frame(int decode_offset) {
  _mode = compiled_mode;

  // Range check to detect ridiculous offsets.
  if (decode_offset == DebugInformationRecorder::serialized_null ||
      decode_offset < 0 ||
      decode_offset >= nm()->scopes_data_size()) {
    // 6379830 AsyncGetCallTrace sometimes feeds us wild frames.
    // If we read nmethod::scopes_data at serialized_null (== 0)
    // or if read some at other invalid offset, invalid values will be decoded.
    // Based on these values, invalid heap locations could be referenced
    // that could lead to crashes in product mode.
    // Therefore, do not use the decode offset if invalid, but fill the frame
    // as it were a native compiled frame (no Java-level assumptions).
#ifdef ASSERT
    if (WizardMode) {
      tty->print_cr("Error in fill_from_frame: pc_desc for "
                    INTPTR_FORMAT " not found or invalid at %d",
                    p2i(_frame.pc()), decode_offset);
      nm()->print();
      nm()->method()->print_codes();
      nm()->print_code();
      nm()->print_pcs();
    }
#endif
    // Provide a cheap fallback in product mode.  (See comment above.)
    found_bad_method_frame();
    fill_from_compiled_native_frame();
    return;
  }

  // Decode first part of scopeDesc
  DebugInfoReadStream buffer(nm(), decode_offset);
  _sender_decode_offset = buffer.read_int();
  _method               = buffer.read_method();
  _bci                  = buffer.read_bci();

  assert(_method->is_method(), "checking type of decoded method");
}

void ThreadLocalAllocBuffer::print_stats(const char* tag) {
  Thread* thrd = myThread();
  size_t waste = _gc_waste + _slow_refill_waste + _fast_refill_waste;
  size_t alloc = _number_of_refills * _desired_size;
  double waste_percent = alloc == 0 ? 0.0 :
                      100.0 * waste / alloc;
  size_t tlab_used  = Universe::heap()->tlab_used(thrd);
  gclog_or_tty->print("TLAB: %s thread: " INTPTR_FORMAT " [id: %2d]"
                      " desired_size: " SIZE_FORMAT "KB"
                      " slow allocs: %d  refill waste: " SIZE_FORMAT "B"
                      " alloc:%8.5f %8.0fKB refills: %d waste %4.1f%% gc: %dB"
                      " slow: %dB fast: %dB\n",
                      tag, p2i(thrd), thrd->osthread()->thread_id(),
                      _desired_size / (K / HeapWordSize),
                      _slow_allocations, _refill_waste_limit * HeapWordSize,
                      _allocation_fraction.average(),
                      _allocation_fraction.average() * tlab_used / K,
                      _number_of_refills, waste_percent,
                      _gc_waste * HeapWordSize,
                      _slow_refill_waste * HeapWordSize,
                      _fast_refill_waste * HeapWordSize);
}

  template <class T> void do_oop_work(T* p) {
    HeapWord* jp = (HeapWord*)p;
    assert(jp >= _begin && jp < _end,
           err_msg("Error: jp " PTR_FORMAT " should be within "
                   "[_begin, _end) = [" PTR_FORMAT "," PTR_FORMAT ")",
                   p2i(jp), p2i(_begin), p2i(_end)));
    oop obj = oopDesc::load_decode_heap_oop(p);
    if (!(obj == NULL || (HeapWord*)obj >= _boundary)) {
      tty->print_cr("pointer " PTR_FORMAT " at " PTR_FORMAT " on "
                    "clean card crosses boundary" PTR_FORMAT,
                    p2i((HeapWord*)obj), p2i(jp), p2i(_boundary));
#ifndef PRODUCT
      obj->print();
#endif
      had_error = true;
    }
  }

inline void assert_different_registers(
    AbstractRegister a,
    AbstractRegister b,
    AbstractRegister c,
    AbstractRegister d,
    AbstractRegister e,
    AbstractRegister f,
    AbstractRegister g,
    AbstractRegister h
) {
    assert(
        a != b && a != c && a != d && a != e && a != f && a != g && a != h
        && b != c && b != d && b != e && b != f && b != g && b != h
        && c != d && c != e && c != f && c != g && c != h
        && d != e && d != f && d != g && d != h
        && e != f && e != g && e != h
        && f != g && f != h
        && g != h,
        "registers must be different: a=" INTPTR_FORMAT ", b=" INTPTR_FORMAT
        ", c=" INTPTR_FORMAT ", d=" INTPTR_FORMAT ", e=" INTPTR_FORMAT
        ", f=" INTPTR_FORMAT ", g=" INTPTR_FORMAT ", h=" INTPTR_FORMAT "",
        p2i(a), p2i(b), p2i(c), p2i(d), p2i(e), p2i(f), p2i(g), p2i(h)
    );
}

void CompiledIC::set_to_clean(bool in_use) {
  assert(SafepointSynchronize::is_at_safepoint() || CompiledIC_lock->is_locked() , "MT-unsafe call");
  if (TraceInlineCacheClearing || TraceICs) {
    tty->print_cr("[email protected]" INTPTR_FORMAT ": set to clean", p2i(instruction_address()));
    print();
  }

  address entry;
  if (is_optimized()) {
    entry = SharedRuntime::get_resolve_opt_virtual_call_stub();
  } else {
    entry = SharedRuntime::get_resolve_virtual_call_stub();
  }

  // A zombie transition will always be safe, since the metadata has already been set to NULL, so
  // we only need to patch the destination
  bool safe_transition = !in_use || is_optimized() || SafepointSynchronize::is_at_safepoint();

  if (safe_transition) {
    // Kill any leftover stub we might have too
    clear_ic_stub();
    if (is_optimized()) {
      set_ic_destination(entry);
    } else {
      set_ic_destination_and_value(entry, (void*)NULL);
    }
  } else {
    // Unsafe transition - create stub.
    InlineCacheBuffer::create_transition_stub(this, NULL, entry);
  }
  // We can't check this anymore. With lazy deopt we could have already
  // cleaned this IC entry before we even return. This is possible if
  // we ran out of space in the inline cache buffer trying to do the
  // set_next and we safepointed to free up space. This is a benign
  // race because the IC entry was complete when we safepointed so
  // cleaning it immediately is harmless.
  // assert(is_clean(), "sanity check");
}

void AdaptiveFreeList<Chunk>::verify_stats() const {
  // The +1 of the LH comparand is to allow some "looseness" in
  // checking: we usually call this interface when adding a block
  // and we'll subsequently update the stats; we cannot update the
  // stats beforehand because in the case of the large-block BT
  // dictionary for example, this might be the first block and
  // in that case there would be no place that we could record
  // the stats (which are kept in the block itself).
  assert((_allocation_stats.prev_sweep() + _allocation_stats.split_births()
          + _allocation_stats.coal_births() + 1)   // Total Production Stock + 1
         >= (_allocation_stats.split_deaths() + _allocation_stats.coal_deaths()
             + (ssize_t)count()),                // Total Current Stock + depletion
         err_msg("FreeList " PTR_FORMAT " of size " SIZE_FORMAT
                 " violates Conservation Principle: "
                 "prev_sweep(" SIZE_FORMAT ")"
                 " + split_births(" SIZE_FORMAT ")"
                 " + coal_births(" SIZE_FORMAT ") + 1 >= "
                 " split_deaths(" SIZE_FORMAT ")"
                 " coal_deaths(" SIZE_FORMAT ")"
                 " + count(" SSIZE_FORMAT ")",
                 p2i(this), size(), _allocation_stats.prev_sweep(), _allocation_stats.split_births(),
                 _allocation_stats.split_births(), _allocation_stats.split_deaths(),
                 _allocation_stats.coal_deaths(), count()));
}

void ClassLoadingService::notify_class_unloaded(InstanceKlass* k) {
  DTRACE_CLASSLOAD_PROBE(unloaded, k, false);
  // Classes that can be unloaded must be non-shared
  _classes_unloaded_count->inc();

  if (UsePerfData) {
    // add the class size
    size_t size = compute_class_size(k);
    _classbytes_unloaded->inc(size);

    // Compute method size & subtract from running total.
    // We are called during phase 1 of mark sweep, so it's
    // still ok to iterate through Method*s here.
    Array<Method*>* methods = k->methods();
    for (int i = 0; i < methods->length(); i++) {
      _class_methods_size->inc(-methods->at(i)->size());
    }
  }

  if (TraceClassUnloading) {
    ResourceMark rm;
    tty->print_cr("[Unloading class %s " INTPTR_FORMAT "]", k->external_name(), p2i(k));
  }
}

inline void assert_different_registers(
  AbstractRegister a,
  AbstractRegister b,
  AbstractRegister c,
  AbstractRegister d,
  AbstractRegister e,
  AbstractRegister f
) {
  assert(
    a != b && a != c && a != d && a != e && a != f
           && b != c && b != d && b != e && b != f
                     && c != d && c != e && c != f
                               && d != e && d != f
                                         && e != f,
    err_msg_res("registers must be different: a=" INTPTR_FORMAT ", b=" INTPTR_FORMAT
                ", c=" INTPTR_FORMAT ", d=" INTPTR_FORMAT ", e=" INTPTR_FORMAT
                ", f=" INTPTR_FORMAT "",
                p2i(a), p2i(b), p2i(c), p2i(d), p2i(e), p2i(f))
  );
}

inline void CompactibleSpace::scan_and_adjust_pointers(SpaceType* space) {
  // adjust all the interior pointers to point at the new locations of objects
  // Used by MarkSweep::mark_sweep_phase3()

  HeapWord* cur_obj = space->bottom();
  HeapWord* const end_of_live = space->_end_of_live;  // Established by "scan_and_forward".
  HeapWord* const first_dead = space->_first_dead;    // Established by "scan_and_forward".

  assert(first_dead <= end_of_live, "Stands to reason, no?");

  const intx interval = PrefetchScanIntervalInBytes;

  debug_only(HeapWord* prev_obj = NULL);
  while (cur_obj < end_of_live) {
    Prefetch::write(cur_obj, interval);
    if (cur_obj < first_dead || oop(cur_obj)->is_gc_marked()) {
      // cur_obj is alive
      // point all the oops to the new location
      size_t size = MarkSweep::adjust_pointers(oop(cur_obj));
      size = space->adjust_obj_size(size);
      debug_only(prev_obj = cur_obj);
      cur_obj += size;
    } else {
      debug_only(prev_obj = cur_obj);
      // cur_obj is not a live object, instead it points at the next live object
      cur_obj = *(HeapWord**)cur_obj;
      assert(cur_obj > prev_obj, "we should be moving forward through memory, cur_obj: " PTR_FORMAT ", prev_obj: " PTR_FORMAT, p2i(cur_obj), p2i(prev_obj));
    }
  }

  assert(cur_obj == end_of_live, "just checking");
}