hotspot/src/share/vm/oops/constantPoolKlass.cpp
author ysr
Thu, 03 Dec 2009 15:01:57 -0800
changeset 4461 c17c526d36ef
parent 2570 ecc7862946d4
child 4584 e2a449e8cc6f
permissions -rw-r--r--
6906727: UseCompressedOops: some card-marking fixes related to object arrays Summary: Introduced a new write_ref_array(HeapWords* start, size_t count) method that does the requisite MemRegion range calculation so (some of the) clients of the erstwhile write_ref_array(MemRegion mr) do not need to worry. This removed all external uses of array_size(), which was also simplified and made private. Asserts were added to catch other possible issues. Further, less essential, fixes stemming from this investigation are deferred to CR 6904516 (to follow shortly in hs17). Reviewed-by: kvn, coleenp, jmasa

/*
 * Copyright 1997-2009 Sun Microsystems, Inc.  All Rights Reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
 * CA 95054 USA or visit www.sun.com if you need additional information or
 * have any questions.
 *
 */

# include "incls/_precompiled.incl"
# include "incls/_constantPoolKlass.cpp.incl"

constantPoolOop constantPoolKlass::allocate(int length, bool is_conc_safe, TRAPS) {
  int size = constantPoolOopDesc::object_size(length);
  KlassHandle klass (THREAD, as_klassOop());
  constantPoolOop c =
    (constantPoolOop)CollectedHeap::permanent_obj_allocate(klass, size, CHECK_NULL);

  c->set_length(length);
  c->set_tags(NULL);
  c->set_cache(NULL);
  c->set_pool_holder(NULL);
  c->set_flags(0);
  // only set to non-zero if constant pool is merged by RedefineClasses
  c->set_orig_length(0);
  // if constant pool may change during RedefineClasses, it is created
  // unsafe for GC concurrent processing.
  c->set_is_conc_safe(is_conc_safe);
  // all fields are initialized; needed for GC

  // initialize tag array
  // Note: cannot introduce constant pool handle before since it is not
  //       completely initialized (no class) -> would cause assertion failure
  constantPoolHandle pool (THREAD, c);
  typeArrayOop t_oop = oopFactory::new_permanent_byteArray(length, CHECK_NULL);
  typeArrayHandle tags (THREAD, t_oop);
  for (int index = 0; index < length; index++) {
    tags()->byte_at_put(index, JVM_CONSTANT_Invalid);
  }
  pool->set_tags(tags());

  return pool();
}

klassOop constantPoolKlass::create_klass(TRAPS) {
  constantPoolKlass o;
  KlassHandle h_this_klass(THREAD, Universe::klassKlassObj());
  KlassHandle k = base_create_klass(h_this_klass, header_size(), o.vtbl_value(), CHECK_NULL);
  // Make sure size calculation is right
  assert(k()->size() == align_object_size(header_size()), "wrong size for object");
  java_lang_Class::create_mirror(k, CHECK_NULL); // Allocate mirror
  return k();
}

int constantPoolKlass::oop_size(oop obj) const {
  assert(obj->is_constantPool(), "must be constantPool");
  return constantPoolOop(obj)->object_size();
}


void constantPoolKlass::oop_follow_contents(oop obj) {
  assert (obj->is_constantPool(), "obj must be constant pool");
  constantPoolOop cp = (constantPoolOop) obj;
  // Performance tweak: We skip iterating over the klass pointer since we
  // know that Universe::constantPoolKlassObj never moves.

  // If the tags array is null we are in the middle of allocating this constant pool
  if (cp->tags() != NULL) {
    // gc of constant pool contents
    oop* base = (oop*)cp->base();
    for (int i = 0; i < cp->length(); i++) {
      if (cp->is_pointer_entry(i)) {
        if (*base != NULL) MarkSweep::mark_and_push(base);
      }
      base++;
    }
    // gc of constant pool instance variables
    MarkSweep::mark_and_push(cp->tags_addr());
    MarkSweep::mark_and_push(cp->cache_addr());
    MarkSweep::mark_and_push(cp->pool_holder_addr());
  }
}

#ifndef SERIALGC
void constantPoolKlass::oop_follow_contents(ParCompactionManager* cm,
                                            oop obj) {
  assert (obj->is_constantPool(), "obj must be constant pool");
  constantPoolOop cp = (constantPoolOop) obj;
  // Performance tweak: We skip iterating over the klass pointer since we
  // know that Universe::constantPoolKlassObj never moves.

  // If the tags array is null we are in the middle of allocating this constant
  // pool.
  if (cp->tags() != NULL) {
    // gc of constant pool contents
    oop* base = (oop*)cp->base();
    for (int i = 0; i < cp->length(); i++) {
      if (cp->is_pointer_entry(i)) {
        if (*base != NULL) PSParallelCompact::mark_and_push(cm, base);
      }
      base++;
    }
    // gc of constant pool instance variables
    PSParallelCompact::mark_and_push(cm, cp->tags_addr());
    PSParallelCompact::mark_and_push(cm, cp->cache_addr());
    PSParallelCompact::mark_and_push(cm, cp->pool_holder_addr());
  }
}
#endif // SERIALGC


int constantPoolKlass::oop_adjust_pointers(oop obj) {
  assert (obj->is_constantPool(), "obj must be constant pool");
  constantPoolOop cp = (constantPoolOop) obj;
  // Get size before changing pointers.
  // Don't call size() or oop_size() since that is a virtual call.
  int size = cp->object_size();
  // Performance tweak: We skip iterating over the klass pointer since we
  // know that Universe::constantPoolKlassObj never moves.

  // If the tags array is null we are in the middle of allocating this constant
  // pool.
  if (cp->tags() != NULL) {
    oop* base = (oop*)cp->base();
    for (int i = 0; i< cp->length();  i++) {
      if (cp->is_pointer_entry(i)) {
        MarkSweep::adjust_pointer(base);
      }
      base++;
    }
  }
  MarkSweep::adjust_pointer(cp->tags_addr());
  MarkSweep::adjust_pointer(cp->cache_addr());
  MarkSweep::adjust_pointer(cp->pool_holder_addr());
  return size;
}


int constantPoolKlass::oop_oop_iterate(oop obj, OopClosure* blk) {
  assert (obj->is_constantPool(), "obj must be constant pool");
  // Performance tweak: We skip iterating over the klass pointer since we
  // know that Universe::constantPoolKlassObj never moves.
  constantPoolOop cp = (constantPoolOop) obj;
  // Get size before changing pointers.
  // Don't call size() or oop_size() since that is a virtual call.
  int size = cp->object_size();

  // If the tags array is null we are in the middle of allocating this constant
  // pool.
  if (cp->tags() != NULL) {
    oop* base = (oop*)cp->base();
    for (int i = 0; i < cp->length(); i++) {
      if (cp->is_pointer_entry(i)) {
        blk->do_oop(base);
      }
      base++;
    }
  }
  blk->do_oop(cp->tags_addr());
  blk->do_oop(cp->cache_addr());
  blk->do_oop(cp->pool_holder_addr());
  return size;
}


int constantPoolKlass::oop_oop_iterate_m(oop obj, OopClosure* blk, MemRegion mr) {
  assert (obj->is_constantPool(), "obj must be constant pool");
  // Performance tweak: We skip iterating over the klass pointer since we
  // know that Universe::constantPoolKlassObj never moves.
  constantPoolOop cp = (constantPoolOop) obj;
  // Get size before changing pointers.
  // Don't call size() or oop_size() since that is a virtual call.
  int size = cp->object_size();

  // If the tags array is null we are in the middle of allocating this constant
  // pool.
  if (cp->tags() != NULL) {
    oop* base = (oop*)cp->base();
    for (int i = 0; i < cp->length(); i++) {
      if (mr.contains(base)) {
        if (cp->is_pointer_entry(i)) {
          blk->do_oop(base);
        }
      }
      base++;
    }
  }
  oop* addr;
  addr = cp->tags_addr();
  blk->do_oop(addr);
  addr = cp->cache_addr();
  blk->do_oop(addr);
  addr = cp->pool_holder_addr();
  blk->do_oop(addr);
  return size;
}

bool constantPoolKlass::oop_is_conc_safe(oop obj) const {
  assert(obj->is_constantPool(), "must be constantPool");
  return constantPoolOop(obj)->is_conc_safe();
}

#ifndef SERIALGC
int constantPoolKlass::oop_update_pointers(ParCompactionManager* cm, oop obj) {
  assert (obj->is_constantPool(), "obj must be constant pool");
  constantPoolOop cp = (constantPoolOop) obj;

  // If the tags array is null we are in the middle of allocating this constant
  // pool.
  if (cp->tags() != NULL) {
    oop* base = (oop*)cp->base();
    for (int i = 0; i < cp->length(); ++i, ++base) {
      if (cp->is_pointer_entry(i)) {
        PSParallelCompact::adjust_pointer(base);
      }
    }
  }
  PSParallelCompact::adjust_pointer(cp->tags_addr());
  PSParallelCompact::adjust_pointer(cp->cache_addr());
  PSParallelCompact::adjust_pointer(cp->pool_holder_addr());
  return cp->object_size();
}

int
constantPoolKlass::oop_update_pointers(ParCompactionManager* cm, oop obj,
                                       HeapWord* beg_addr, HeapWord* end_addr) {
  assert (obj->is_constantPool(), "obj must be constant pool");
  constantPoolOop cp = (constantPoolOop) obj;

  // If the tags array is null we are in the middle of allocating this constant
  // pool.
  if (cp->tags() != NULL) {
    oop* base = (oop*)cp->base();
    oop* const beg_oop = MAX2((oop*)beg_addr, base);
    oop* const end_oop = MIN2((oop*)end_addr, base + cp->length());
    const size_t beg_idx = pointer_delta(beg_oop, base, sizeof(oop*));
    const size_t end_idx = pointer_delta(end_oop, base, sizeof(oop*));
    for (size_t cur_idx = beg_idx; cur_idx < end_idx; ++cur_idx, ++base) {
      if (cp->is_pointer_entry(int(cur_idx))) {
        PSParallelCompact::adjust_pointer(base);
      }
    }
  }

  oop* p;
  p = cp->tags_addr();
  PSParallelCompact::adjust_pointer(p, beg_addr, end_addr);
  p = cp->cache_addr();
  PSParallelCompact::adjust_pointer(p, beg_addr, end_addr);
  p = cp->pool_holder_addr();
  PSParallelCompact::adjust_pointer(p, beg_addr, end_addr);

  return cp->object_size();
}

void constantPoolKlass::oop_copy_contents(PSPromotionManager* pm, oop obj) {
  assert(obj->is_constantPool(), "should be constant pool");
  constantPoolOop cp = (constantPoolOop) obj;
  if (AnonymousClasses && cp->has_pseudo_string() && cp->tags() != NULL) {
    oop* base = (oop*)cp->base();
    for (int i = 0; i < cp->length(); ++i, ++base) {
      if (cp->tag_at(i).is_string()) {
        if (PSScavenge::should_scavenge(base)) {
          pm->claim_or_forward_breadth(base);
        }
      }
    }
  }
}

void constantPoolKlass::oop_push_contents(PSPromotionManager* pm, oop obj) {
  assert(obj->is_constantPool(), "should be constant pool");
  constantPoolOop cp = (constantPoolOop) obj;
  if (AnonymousClasses && cp->has_pseudo_string() && cp->tags() != NULL) {
    oop* base = (oop*)cp->base();
    for (int i = 0; i < cp->length(); ++i, ++base) {
      if (cp->tag_at(i).is_string()) {
        if (PSScavenge::should_scavenge(base)) {
          pm->claim_or_forward_depth(base);
        }
      }
    }
  }
}
#endif // SERIALGC

#ifndef PRODUCT

// Printing

void constantPoolKlass::oop_print_on(oop obj, outputStream* st) {
  EXCEPTION_MARK;
  oop anObj;
  assert(obj->is_constantPool(), "must be constantPool");
  Klass::oop_print_on(obj, st);
  constantPoolOop cp = constantPoolOop(obj);
  if (cp->flags() != 0) {
    st->print(" - flags : 0x%x", cp->flags());
    if (cp->has_pseudo_string()) st->print(" has_pseudo_string");
    if (cp->has_invokedynamic()) st->print(" has_invokedynamic");
    st->cr();
  }

  // Temp. remove cache so we can do lookups with original indicies.
  constantPoolCacheHandle cache (THREAD, cp->cache());
  cp->set_cache(NULL);

  for (int index = 1; index < cp->length(); index++) {      // Index 0 is unused
    st->print(" - %3d : ", index);
    cp->tag_at(index).print_on(st);
    st->print(" : ");
    switch (cp->tag_at(index).value()) {
      case JVM_CONSTANT_Class :
        { anObj = cp->klass_at(index, CATCH);
          anObj->print_value_on(st);
          st->print(" {0x%lx}", (address)anObj);
        }
        break;
      case JVM_CONSTANT_Fieldref :
      case JVM_CONSTANT_Methodref :
      case JVM_CONSTANT_InterfaceMethodref :
        st->print("klass_index=%d", cp->klass_ref_index_at(index));
        st->print(" name_and_type_index=%d", cp->name_and_type_ref_index_at(index));
        break;
      case JVM_CONSTANT_UnresolvedString :
      case JVM_CONSTANT_String :
        if (cp->is_pseudo_string_at(index)) {
          anObj = cp->pseudo_string_at(index);
        } else {
          anObj = cp->string_at(index, CATCH);
        }
        anObj->print_value_on(st);
        st->print(" {0x%lx}", (address)anObj);
        break;
      case JVM_CONSTANT_Integer :
        st->print("%d", cp->int_at(index));
        break;
      case JVM_CONSTANT_Float :
        st->print("%f", cp->float_at(index));
        break;
      case JVM_CONSTANT_Long :
        st->print_jlong(cp->long_at(index));
        index++;   // Skip entry following eigth-byte constant
        break;
      case JVM_CONSTANT_Double :
        st->print("%lf", cp->double_at(index));
        index++;   // Skip entry following eigth-byte constant
        break;
      case JVM_CONSTANT_NameAndType :
        st->print("name_index=%d", cp->name_ref_index_at(index));
        st->print(" signature_index=%d", cp->signature_ref_index_at(index));
        break;
      case JVM_CONSTANT_Utf8 :
        cp->symbol_at(index)->print_value_on(st);
        break;
      case JVM_CONSTANT_UnresolvedClass :               // fall-through
      case JVM_CONSTANT_UnresolvedClassInError: {
        // unresolved_klass_at requires lock or safe world.
        oop entry = *cp->obj_at_addr(index);
        entry->print_value_on(st);
        }
        break;
      default:
        ShouldNotReachHere();
        break;
    }
    st->cr();
  }
  st->cr();

  // Restore cache
  cp->set_cache(cache());
}


#endif

const char* constantPoolKlass::internal_name() const {
  return "{constant pool}";
}

// Verification

void constantPoolKlass::oop_verify_on(oop obj, outputStream* st) {
  Klass::oop_verify_on(obj, st);
  guarantee(obj->is_constantPool(), "object must be constant pool");
  constantPoolOop cp = constantPoolOop(obj);
  guarantee(cp->is_perm(), "should be in permspace");
  if (!cp->partially_loaded()) {
    oop* base = (oop*)cp->base();
    for (int i = 0; i< cp->length();  i++) {
      if (cp->tag_at(i).is_klass()) {
        guarantee((*base)->is_perm(),     "should be in permspace");
        guarantee((*base)->is_klass(),    "should be klass");
      }
      if (cp->tag_at(i).is_unresolved_klass()) {
        guarantee((*base)->is_perm(),     "should be in permspace");
        guarantee((*base)->is_symbol() || (*base)->is_klass(),
                  "should be symbol or klass");
      }
      if (cp->tag_at(i).is_symbol()) {
        guarantee((*base)->is_perm(),     "should be in permspace");
        guarantee((*base)->is_symbol(),   "should be symbol");
      }
      if (cp->tag_at(i).is_unresolved_string()) {
        guarantee((*base)->is_perm(),     "should be in permspace");
        guarantee((*base)->is_symbol() || (*base)->is_instance(),
                  "should be symbol or instance");
      }
      if (cp->tag_at(i).is_string()) {
        if (!cp->has_pseudo_string()) {
          guarantee((*base)->is_perm(),   "should be in permspace");
          guarantee((*base)->is_instance(), "should be instance");
        } else {
          // can be non-perm, can be non-instance (array)
        }
      }
      base++;
    }
    guarantee(cp->tags()->is_perm(),         "should be in permspace");
    guarantee(cp->tags()->is_typeArray(),    "should be type array");
    if (cp->cache() != NULL) {
      // Note: cache() can be NULL before a class is completely setup or
      // in temporary constant pools used during constant pool merging
      guarantee(cp->cache()->is_perm(),              "should be in permspace");
      guarantee(cp->cache()->is_constantPoolCache(), "should be constant pool cache");
    }
    if (cp->pool_holder() != NULL) {
      // Note: pool_holder() can be NULL in temporary constant pools
      // used during constant pool merging
      guarantee(cp->pool_holder()->is_perm(),  "should be in permspace");
      guarantee(cp->pool_holder()->is_klass(), "should be klass");
    }
  }
}

bool constantPoolKlass::oop_partially_loaded(oop obj) const {
  assert(obj->is_constantPool(), "object must be constant pool");
  constantPoolOop cp = constantPoolOop(obj);
  return cp->tags() == NULL || cp->pool_holder() == (klassOop) cp;   // Check whether pool holder points to self
}


void constantPoolKlass::oop_set_partially_loaded(oop obj) {
  assert(obj->is_constantPool(), "object must be constant pool");
  constantPoolOop cp = constantPoolOop(obj);
  assert(cp->pool_holder() == NULL, "just checking");
  cp->set_pool_holder((klassOop) cp);   // Temporarily set pool holder to point to self
}

#ifndef PRODUCT
// CompileTheWorld support. Preload all classes loaded references in the passed in constantpool
void constantPoolKlass::preload_and_initialize_all_classes(oop obj, TRAPS) {
  guarantee(obj->is_constantPool(), "object must be constant pool");
  constantPoolHandle cp(THREAD, (constantPoolOop)obj);
  guarantee(!cp->partially_loaded(), "must be fully loaded");

  for (int i = 0; i< cp->length();  i++) {
    if (cp->tag_at(i).is_unresolved_klass()) {
      // This will force loading of the class
      klassOop klass = cp->klass_at(i, CHECK);
      if (klass->is_instance()) {
        // Force initialization of class
        instanceKlass::cast(klass)->initialize(CHECK);
      }
    }
  }
}

#endif