< prev index next >

src/hotspot/share/services/heapDumper.cpp

Print this page
@@ -40,13 +40,16 @@
  #include "memory/universe.hpp"
  #include "oops/fieldStreams.inline.hpp"
  #include "oops/klass.inline.hpp"
  #include "oops/objArrayKlass.hpp"
  #include "oops/objArrayOop.inline.hpp"
+ #include "oops/flatArrayKlass.hpp"
+ #include "oops/flatArrayOop.inline.hpp"
  #include "oops/oop.inline.hpp"
  #include "oops/typeArrayOop.inline.hpp"
  #include "runtime/continuationWrapper.inline.hpp"
+ #include "runtime/fieldDescriptor.inline.hpp"
  #include "runtime/frame.inline.hpp"
  #include "runtime/handles.inline.hpp"
  #include "runtime/javaCalls.hpp"
  #include "runtime/javaThread.inline.hpp"
  #include "runtime/jniHandles.hpp"

@@ -314,10 +317,32 @@
   *
   *                u4        0x00000001: alloc traces on/off
   *                          0x00000002: cpu sampling on/off
   *                u2        stack trace depth
   *
+  * HPROF_FLAT_ARRAYS        list of flat arrays
+  *
+  *               [flat array sub-records]*
+  *
+  *               HPROF_FLAT_ARRAY      flat array
+  *
+  *                          id         array object ID (dumped as HPROF_GC_PRIM_ARRAY_DUMP)
+  *                          id         element class ID (dumped by HPROF_GC_CLASS_DUMP)
+  *
+  * HPROF_INLINED_FIELDS     decribes inlined fields
+  *
+  *               [class with inlined fields sub-records]*
+  *
+  *               HPROF_CLASS_WITH_INLINED_FIELDS
+  *
+  *                          id         class ID (dumped as HPROF_GC_CLASS_DUMP)
+  *
+  *                          u2         number of instance inlined fields (not including super)
+  *                          [u2,       inlined field index,
+  *                           u2,       synthetic field count,
+  *                           id,       original field name,
+  *                           id]*      inlined field class ID (dumped by HPROF_GC_CLASS_DUMP)
   *
   * When the header is "JAVA PROFILE 1.0.2" a heap dump can optionally
   * be generated as a sequence of heap dump segments. This sequence is
   * terminated by an end record. The additional tags allowed by format
   * "JAVA PROFILE 1.0.2" are:

@@ -351,10 +376,17 @@
  
    // 1.0.2 record types
    HPROF_HEAP_DUMP_SEGMENT       = 0x1C,
    HPROF_HEAP_DUMP_END           = 0x2C,
  
+   // inlined object support
+   HPROF_FLAT_ARRAYS             = 0x12,
+   HPROF_INLINED_FIELDS          = 0x13,
+   // inlined object subrecords
+   HPROF_FLAT_ARRAY                  = 0x01,
+   HPROF_CLASS_WITH_INLINED_FIELDS   = 0x01,
+ 
    // field types
    HPROF_ARRAY_OBJECT            = 0x01,
    HPROF_NORMAL_OBJECT           = 0x02,
    HPROF_BOOLEAN                 = 0x04,
    HPROF_CHAR                    = 0x05,

@@ -385,10 +417,75 @@
  enum {
    STACK_TRACE_ID = 1,
    INITIAL_CLASS_COUNT = 200
  };
  
+ 
+ class AbstractDumpWriter;
+ 
+ class InlinedObjects {
+ 
+   struct ClassInlinedFields {
+     const Klass *klass;
+     uintx base_index;   // base index of the inlined field names (1st field has index base_index+1).
+     ClassInlinedFields(const Klass *klass = nullptr, uintx base_index = 0) : klass(klass), base_index(base_index) {}
+ 
+     // For GrowableArray::find_sorted().
+     static int compare(const ClassInlinedFields& a, const ClassInlinedFields& b) {
+       return a.klass - b.klass;
+     }
+     // For GrowableArray::sort().
+     static int compare(ClassInlinedFields* a, ClassInlinedFields* b) {
+       return compare(*a, *b);
+     }
+   };
+ 
+   uintx _min_string_id;
+   uintx _max_string_id;
+ 
+   GrowableArray<ClassInlinedFields> *_inlined_field_map;
+ 
+   // counters for classes with inlined fields and for the fields
+   int _classes_count;
+   int _inlined_fields_count;
+ 
+   static InlinedObjects *_instance;
+ 
+   static void inlined_field_names_callback(InlinedObjects* _this, const Klass *klass, uintx base_index, int count);
+ 
+   GrowableArray<oop> *_flat_arrays;
+ 
+ public:
+   InlinedObjects()
+     : _min_string_id(0), _max_string_id(0),
+     _inlined_field_map(nullptr),
+     _classes_count(0), _inlined_fields_count(0),
+     _flat_arrays(nullptr) {
+   }
+ 
+   static InlinedObjects* get_instance() {
+     return _instance;
+   }
+ 
+   void init();
+   void release();
+ 
+   void dump_inlined_field_names(AbstractDumpWriter *writer);
+ 
+   uintx get_base_index_for(Klass* k);
+   uintx get_next_string_id(uintx id);
+ 
+   void dump_classed_with_inlined_fields(AbstractDumpWriter* writer);
+ 
+   void add_flat_array(oop array);
+   void dump_flat_arrays(AbstractDumpWriter* writer);
+ 
+ };
+ 
+ InlinedObjects *InlinedObjects::_instance = nullptr;
+ 
+ 
  // Supports I/O operations for a dump
  // Base class for dump and parallel dump
  class AbstractDumpWriter : public CHeapObj<mtInternal> {
   protected:
    enum {

@@ -737,11 +834,11 @@
    // returns hprof tag for the given basic type
    static hprofTag type2tag(BasicType type);
    // Returns the size of the data to write.
    static u4 sig2size(Symbol* sig);
  
-   // returns the size of the instance of the given class
+   // calculates the total size of the all fields of the given class.
    static u4 instance_size(InstanceKlass* ik, DumperClassCacheTableEntry* class_cache_entry = nullptr);
  
    // dump a jfloat
    static void dump_float(AbstractDumpWriter* writer, jfloat f);
    // dump a jdouble

@@ -750,32 +847,43 @@
    static void dump_field_value(AbstractDumpWriter* writer, char type, oop obj, int offset);
    // returns the size of the static fields; also counts the static fields
    static u4 get_static_fields_size(InstanceKlass* ik, u2& field_count);
    // dumps static fields of the given class
    static void dump_static_fields(AbstractDumpWriter* writer, Klass* k);
-   // dump the raw values of the instance fields of the given object
-   static void dump_instance_fields(AbstractDumpWriter* writer, oop o, DumperClassCacheTableEntry* class_cache_entry);
+   // dump the raw values of the instance fields of the given identity or inlined object;
+   // for identity objects offset is 0 and 'klass' is o->klass(),
+   // for inlined objects offset is the offset in the holder object, 'klass' is inlined object class
+   static void dump_instance_fields(AbstractDumpWriter* writer, oop o, int offset, DumperClassCacheTable* class_cache, DumperClassCacheTableEntry* class_cache_entry);
+   // dump the raw values of the instance fields of the given inlined object;
+   // dump_instance_fields wrapper for inlined objects
+   static void dump_inlined_object_fields(AbstractDumpWriter* writer, oop o, int offset, DumperClassCacheTable* class_cache, DumperClassCacheTableEntry* class_cache_entry);
+ 
    // get the count of the instance fields for a given class
    static u2 get_instance_fields_count(InstanceKlass* ik);
    // dumps the definition of the instance fields for a given class
-   static void dump_instance_field_descriptors(AbstractDumpWriter* writer, Klass* k);
+   static void dump_instance_field_descriptors(AbstractDumpWriter* writer, InstanceKlass* k, uintx *inlined_fields_index = nullptr);
    // creates HPROF_GC_INSTANCE_DUMP record for the given object
    static void dump_instance(AbstractDumpWriter* writer, oop o, DumperClassCacheTable* class_cache);
    // creates HPROF_GC_CLASS_DUMP record for the given instance class
    static void dump_instance_class(AbstractDumpWriter* writer, Klass* k);
    // creates HPROF_GC_CLASS_DUMP record for a given array class
    static void dump_array_class(AbstractDumpWriter* writer, Klass* k);
  
    // creates HPROF_GC_OBJ_ARRAY_DUMP record for the given object array
    static void dump_object_array(AbstractDumpWriter* writer, objArrayOop array);
+   // creates HPROF_GC_PRIM_ARRAY_DUMP record for the given flat array
+   static void dump_flat_array(AbstractDumpWriter* writer, flatArrayOop array, DumperClassCacheTable* class_cache);
    // creates HPROF_GC_PRIM_ARRAY_DUMP record for the given type array
    static void dump_prim_array(AbstractDumpWriter* writer, typeArrayOop array);
    // create HPROF_FRAME record for the given method and bci
    static void dump_stack_frame(AbstractDumpWriter* writer, int frame_serial_num, int class_serial_num, Method* m, int bci);
  
    // check if we need to truncate an array
    static int calculate_array_max_length(AbstractDumpWriter* writer, arrayOop array, short header_size);
+   // extended version to dump flat arrays as primitive arrays;
+   // type_size specifies size of the inlined objects.
+   static int calculate_array_max_length(AbstractDumpWriter* writer, arrayOop array, int type_size, short header_size);
  
    // fixes up the current dump record and writes HPROF_HEAP_DUMP_END record
    static void end_of_dump(AbstractDumpWriter* writer);
  
    static oop mask_dormant_archived_object(oop o, oop ref_obj) {

@@ -787,10 +895,20 @@
      } else {
        return o;
      }
    }
  
+   // helper methods for inlined fields.
+   static bool is_inlined_field(const fieldDescriptor& fld) {
+     return fld.is_flat();
+   }
+   static InlineKlass* get_inlined_field_klass(const fieldDescriptor& fld) {
+     assert(is_inlined_field(fld), "must be inlined field");
+     InstanceKlass* holder_klass = fld.field_holder();
+     return InlineKlass::cast(holder_klass->get_inline_type_field_klass(fld.index()));
+   }
+ 
    static void report_dormant_archived_object(oop o, oop ref_obj) {
      if (log_is_enabled(Trace, cds, heap)) {
        ResourceMark rm;
        if (ref_obj != nullptr) {
          log_trace(cds, heap)("skipped dormant archived object " INTPTR_FORMAT " (%s) referenced by " INTPTR_FORMAT " (%s)",

@@ -811,18 +929,22 @@
  class DumperClassCacheTableEntry : public CHeapObj<mtServiceability> {
    friend class DumperClassCacheTable;
  private:
    GrowableArray<char> _sigs_start;
    GrowableArray<int> _offsets;
+   GrowableArray<InlineKlass*> _inline_klasses;
    u4 _instance_size;
    int _entries;
  
  public:
    DumperClassCacheTableEntry() : _instance_size(0), _entries(0) {};
  
    int field_count()             { return _entries; }
    char sig_start(int field_idx) { return _sigs_start.at(field_idx); }
+   void push_sig_start_inlined() { _sigs_start.push('Q'); }
+   bool is_inlined(int field_idx){ return _sigs_start.at(field_idx) == 'Q'; }
+   InlineKlass* inline_klass(int field_idx) { assert(is_inlined(field_idx), "Not inlined"); return _inline_klasses.at(field_idx); }
    int offset(int field_idx)     { return _offsets.at(field_idx); }
    u4 instance_size()            { return _instance_size; }
  };
  
  class DumperClassCacheTable {

@@ -867,15 +989,23 @@
      DumperClassCacheTableEntry** from_cache = _ptrs->get(ik);
      if (from_cache == nullptr) {
        entry = new DumperClassCacheTableEntry();
        for (HierarchicalFieldStream<JavaFieldStream> fld(ik); !fld.done(); fld.next()) {
          if (!fld.access_flags().is_static()) {
-           Symbol* sig = fld.signature();
-           entry->_sigs_start.push(sig->char_at(0));
+           InlineKlass* inlineKlass = nullptr;
+           if (DumperSupport::is_inlined_field(fld.field_descriptor())) {
+             inlineKlass = DumperSupport::get_inlined_field_klass(fld.field_descriptor());
+             entry->push_sig_start_inlined();
+             entry->_instance_size += DumperSupport::instance_size(inlineKlass);
+           } else {
+             Symbol* sig = fld.signature();
+             entry->_sigs_start.push(sig->char_at(0));
+             entry->_instance_size += DumperSupport::sig2size(sig);
+           }
+           entry->_inline_klasses.push(inlineKlass);
            entry->_offsets.push(fld.offset());
            entry->_entries++;
-           entry->_instance_size += DumperSupport::sig2size(sig);
          }
        }
  
        if (_ptrs->number_of_entries() >= CACHE_TOP) {
          // We do not track the individual hit rates for table entries.

@@ -981,10 +1111,11 @@
    } else {
      writer->write_u8(bit_cast<u8>(d));
    }
  }
  
+ 
  // dumps the raw value of the given field
  void DumperSupport::dump_field_value(AbstractDumpWriter* writer, char type, oop obj, int offset) {
    switch (type) {
      case JVM_SIGNATURE_CLASS :
      case JVM_SIGNATURE_ARRAY : {

@@ -1039,19 +1170,23 @@
        break;
      }
    }
  }
  
- // returns the size of the instance of the given class
+ // calculates the total size of the all fields of the given class.
  u4 DumperSupport::instance_size(InstanceKlass* ik, DumperClassCacheTableEntry* class_cache_entry) {
    if (class_cache_entry != nullptr) {
      return class_cache_entry->instance_size();
    } else {
      u4 size = 0;
      for (HierarchicalFieldStream<JavaFieldStream> fld(ik); !fld.done(); fld.next()) {
        if (!fld.access_flags().is_static()) {
-         size += sig2size(fld.signature());
+         if (is_inlined_field(fld.field_descriptor())) {
+           size += instance_size(get_inlined_field_klass(fld.field_descriptor()));
+         } else {
+           size += sig2size(fld.signature());
+         }
        }
      }
      return size;
    }
  }

@@ -1060,10 +1195,12 @@
    field_count = 0;
    u4 size = 0;
  
    for (JavaFieldStream fldc(ik); !fldc.done(); fldc.next()) {
      if (fldc.access_flags().is_static()) {
+       assert(!is_inlined_field(fldc.field_descriptor()), "static fields cannot be inlined");
+ 
        field_count++;
        size += sig2size(fldc.signature());
      }
    }
  

@@ -1094,10 +1231,12 @@
    InstanceKlass* ik = InstanceKlass::cast(k);
  
    // dump the field descriptors and raw values
    for (JavaFieldStream fld(ik); !fld.done(); fld.next()) {
      if (fld.access_flags().is_static()) {
+       assert(!is_inlined_field(fld.field_descriptor()), "static fields cannot be inlined");
+ 
        Symbol* sig = fld.signature();
  
        writer->write_symbolID(fld.name());   // name
        writer->write_u1(sig2tag(sig));       // type
  

@@ -1122,40 +1261,90 @@
        prev = prev->previous_versions();
      }
    }
  }
  
- // dump the raw values of the instance fields of the given object
- void DumperSupport::dump_instance_fields(AbstractDumpWriter* writer, oop o, DumperClassCacheTableEntry* class_cache_entry) {
+ // dump the raw values of the instance fields of the given identity or inlined object;
+ // for identity objects offset is 0 and 'klass' is o->klass(),
+ // for inlined objects offset is the offset in the holder object, 'klass' is inlined object class.
+ void DumperSupport::dump_instance_fields(AbstractDumpWriter* writer, oop o, int offset, DumperClassCacheTable* class_cache, DumperClassCacheTableEntry* class_cache_entry) {
    assert(class_cache_entry != nullptr, "Pre-condition: must be provided");
    for (int idx = 0; idx < class_cache_entry->field_count(); idx++) {
-     dump_field_value(writer, class_cache_entry->sig_start(idx), o, class_cache_entry->offset(idx));
+     if (class_cache_entry->is_inlined(idx)) {
+       InlineKlass* field_klass = class_cache_entry->inline_klass(idx);
+       int fields_offset = offset + (class_cache_entry->offset(idx) - field_klass->first_field_offset());
+       DumperClassCacheTableEntry* inline_class_cache_entry = class_cache->lookup_or_create(field_klass);
+       dump_inlined_object_fields(writer, o, fields_offset, class_cache, inline_class_cache_entry);
+     } else {
+       dump_field_value(writer, class_cache_entry->sig_start(idx), o, class_cache_entry->offset(idx));
+     }
    }
  }
  
- // dumps the definition of the instance fields for a given class
+ void DumperSupport::dump_inlined_object_fields(AbstractDumpWriter* writer, oop o, int offset, DumperClassCacheTable* class_cache, DumperClassCacheTableEntry* class_cache_entry) {
+   // the object is inlined, so all its fields are stored without headers.
+   dump_instance_fields(writer, o, offset, class_cache, class_cache_entry);
+ }
+ 
+ // gets the count of the instance fields for a given class
  u2 DumperSupport::get_instance_fields_count(InstanceKlass* ik) {
    u2 field_count = 0;
  
    for (JavaFieldStream fldc(ik); !fldc.done(); fldc.next()) {
-     if (!fldc.access_flags().is_static()) field_count++;
+     if (!fldc.access_flags().is_static()) {
+       if (is_inlined_field(fldc.field_descriptor())) {
+         // add "synthetic" fields for inlined fields.
+         field_count += get_instance_fields_count(get_inlined_field_klass(fldc.field_descriptor()));
+       } else {
+         field_count++;
+       }
+     }
    }
  
    return field_count;
  }
  
  // dumps the definition of the instance fields for a given class
- void DumperSupport::dump_instance_field_descriptors(AbstractDumpWriter* writer, Klass* k) {
-   InstanceKlass* ik = InstanceKlass::cast(k);
+ // inlined_fields_id is not-nullptr for inlined fields (to get synthetic field name IDs
+ // by using InlinedObjects::get_next_string_id()).
+ void DumperSupport::dump_instance_field_descriptors(AbstractDumpWriter* writer, InstanceKlass* ik, uintx* inlined_fields_id) {
+   // inlined_fields_id != nullptr means ik is a class of inlined field.
+   // Inlined field id pointer for this class; lazyly initialized
+   // if the class has inlined field(s) and the caller didn't provide inlined_fields_id.
+   uintx *this_klass_inlined_fields_id = inlined_fields_id;
+   uintx inlined_id = 0;
  
    // dump the field descriptors
    for (JavaFieldStream fld(ik); !fld.done(); fld.next()) {
      if (!fld.access_flags().is_static()) {
-       Symbol* sig = fld.signature();
+       if (is_inlined_field(fld.field_descriptor())) {
+         // dump "synthetic" fields for inlined fields.
+         if (this_klass_inlined_fields_id == nullptr) {
+           inlined_id = InlinedObjects::get_instance()->get_base_index_for(ik);
+           this_klass_inlined_fields_id = &inlined_id;
+         }
+         dump_instance_field_descriptors(writer, get_inlined_field_klass(fld.field_descriptor()), this_klass_inlined_fields_id);
+       } else {
+         Symbol* sig = fld.signature();
+         Symbol* name = nullptr;
+         // Use inlined_fields_id provided by caller.
+         if (inlined_fields_id != nullptr) {
+           uintx name_id = InlinedObjects::get_instance()->get_next_string_id(*inlined_fields_id);
+ 
+           // name_id == 0 is returned on error. use original field signature.
+           if (name_id != 0) {
+             *inlined_fields_id = name_id;
+             name = reinterpret_cast<Symbol*>(name_id);
+           }
+         }
+         if (name == nullptr) {
+           name = fld.name();
+         }
  
-       writer->write_symbolID(fld.name());   // name
-       writer->write_u1(sig2tag(sig));       // type
+         writer->write_symbolID(name);         // name
+         writer->write_u1(sig2tag(sig));       // type
+       }
      }
    }
  }
  
  // creates HPROF_GC_INSTANCE_DUMP record for the given object

@@ -1176,11 +1365,11 @@
  
    // number of bytes that follow
    writer->write_u4(is);
  
    // field values
-   dump_instance_fields(writer, o, cache_entry);
+   dump_instance_fields(writer, o, 0, class_cache, cache_entry);
  
    writer->end_sub_record();
  }
  
  // creates HPROF_GC_CLASS_DUMP record for the given instance class

@@ -1221,11 +1410,11 @@
    // reserved
    writer->write_objectID(oop(nullptr));
    writer->write_objectID(oop(nullptr));
  
    // instance size
-   writer->write_u4(DumperSupport::instance_size(ik));
+   writer->write_u4(HeapWordSize * ik->size_helper());
  
    // size of constant pool - ignored by HAT 1.1
    writer->write_u2(0);
  
    // static fields

@@ -1275,36 +1464,43 @@
  
  }
  
  // Hprof uses an u4 as record length field,
  // which means we need to truncate arrays that are too long.
- int DumperSupport::calculate_array_max_length(AbstractDumpWriter* writer, arrayOop array, short header_size) {
-   BasicType type = ArrayKlass::cast(array->klass())->element_type();
-   assert(type >= T_BOOLEAN && type <= T_OBJECT, "invalid array element type");
- 
+ int DumperSupport::calculate_array_max_length(AbstractDumpWriter* writer, arrayOop array, int type_size, short header_size) {
    int length = array->length();
  
-   int type_size;
-   if (type == T_OBJECT) {
-     type_size = sizeof(address);
-   } else {
-     type_size = type2aelembytes(type);
-   }
- 
    size_t length_in_bytes = (size_t)length * type_size;
    uint max_bytes = max_juint - header_size;
  
    if (length_in_bytes > max_bytes) {
      length = max_bytes / type_size;
      length_in_bytes = (size_t)length * type_size;
  
+     BasicType type = ArrayKlass::cast(array->klass())->element_type();
      warning("cannot dump array of type %s[] with length %d; truncating to length %d",
              type2name_tab[type], array->length(), length);
    }
    return length;
  }
  
+ int DumperSupport::calculate_array_max_length(AbstractDumpWriter* writer, arrayOop array, short header_size) {
+   BasicType type = ArrayKlass::cast(array->klass())->element_type();
+   assert((type >= T_BOOLEAN && type <= T_OBJECT) || type == T_PRIMITIVE_OBJECT, "invalid array element type");
+   int type_size;
+   if (type == T_OBJECT) {
+     type_size = sizeof(address);
+   } else if (type == T_PRIMITIVE_OBJECT) {
+       // TODO: FIXME
+       fatal("Not supported yet"); // FIXME: JDK-8325678
+   } else {
+     type_size = type2aelembytes(type);
+   }
+ 
+   return calculate_array_max_length(writer, array, type_size, header_size);
+ }
+ 
  // creates HPROF_GC_OBJ_ARRAY_DUMP record for the given object array
  void DumperSupport::dump_object_array(AbstractDumpWriter* writer, objArrayOop array) {
    // sizeof(u1) + 2 * sizeof(u4) + sizeof(objectID) + sizeof(classID)
    short header_size = 1 + 2 * 4 + 2 * sizeof(address);
    int length = calculate_array_max_length(writer, array, header_size);

@@ -1326,10 +1522,51 @@
    }
  
    writer->end_sub_record();
  }
  
+ // creates HPROF_GC_PRIM_ARRAY_DUMP record for the given flat array
+ void DumperSupport::dump_flat_array(AbstractDumpWriter* writer, flatArrayOop array, DumperClassCacheTable* class_cache) {
+   FlatArrayKlass* array_klass = FlatArrayKlass::cast(array->klass());
+   InlineKlass* element_klass = array_klass->element_klass();
+   int element_size = instance_size(element_klass);
+   /*                          id         array object ID
+    *                          u4         stack trace serial number
+    *                          u4         number of elements
+    *                          u1         element type
+    */
+   short header_size = 1 + sizeof(address) + 2 * 4 + 1;
+ 
+   // TODO: use T_SHORT/T_INT/T_LONG if needed to avoid truncation
+   BasicType type = T_BYTE;
+   int type_size = type2aelembytes(type);
+   int length = calculate_array_max_length(writer, array, element_size, header_size);
+   u4 length_in_bytes = (u4)(length * element_size);
+   u4 size = header_size + length_in_bytes;
+ 
+   writer->start_sub_record(HPROF_GC_PRIM_ARRAY_DUMP, size);
+   writer->write_objectID(array);
+   writer->write_u4(STACK_TRACE_ID);
+   // TODO: round up array length for T_SHORT/T_INT/T_LONG
+   writer->write_u4(length * element_size);
+   writer->write_u1(type2tag(type));
+ 
+   for (int index = 0; index < length; index++) {
+     // need offset in the holder to read inlined object. calculate it from flatArrayOop::value_at_addr()
+     int offset = (int)((address)array->value_at_addr(index, array_klass->layout_helper())
+                   - cast_from_oop<address>(array));
+     DumperClassCacheTableEntry* class_cache_entry = class_cache->lookup_or_create(element_klass);
+     dump_inlined_object_fields(writer, array, offset, class_cache, class_cache_entry);
+   }
+ 
+   // TODO: write padding bytes for T_SHORT/T_INT/T_LONG
+ 
+   InlinedObjects::get_instance()->add_flat_array(array);
+ 
+   writer->end_sub_record();
+ }
+ 
  #define WRITE_ARRAY(Array, Type, Size, Length) \
    for (int i = 0; i < Length; i++) { writer->write_##Size((Size)Array->Type##_at(i)); }
  
  // creates HPROF_GC_PRIM_ARRAY_DUMP record for the given type array
  void DumperSupport::dump_prim_array(AbstractDumpWriter* writer, typeArrayOop array) {

@@ -1447,10 +1684,274 @@
    writer->write_u4(class_serial_num);               // class serial number
    writer->write_u4((u4) line_number);               // line number
  }
  
  
+ class InlinedFieldNameDumper : public LockedClassesDo {
+ public:
+   typedef void (*Callback)(InlinedObjects *owner, const Klass *klass, uintx base_index, int count);
+ 
+ private:
+   AbstractDumpWriter* _writer;
+   InlinedObjects *_owner;
+   Callback       _callback;
+   uintx _index;
+ 
+   void dump_inlined_field_names(GrowableArray<Symbol*>* super_names, Symbol* field_name, InlineKlass* klass) {
+     super_names->push(field_name);
+     for (HierarchicalFieldStream<JavaFieldStream> fld(klass); !fld.done(); fld.next()) {
+       if (!fld.access_flags().is_static()) {
+         if (DumperSupport::is_inlined_field(fld.field_descriptor())) {
+           dump_inlined_field_names(super_names, fld.name(), DumperSupport::get_inlined_field_klass(fld.field_descriptor()));
+         } else {
+           // get next string ID.
+           uintx next_index = _owner->get_next_string_id(_index);
+           if (next_index == 0) {
+             // something went wrong (overflow?)
+             // stop generation; the rest of inlined objects will have original field names.
+             return;
+           }
+           _index = next_index;
+ 
+           // Calculate length.
+           int len = fld.name()->utf8_length();
+           for (GrowableArrayIterator<Symbol*> it = super_names->begin(); it != super_names->end(); ++it) {
+             len += (*it)->utf8_length() + 1;    // +1 for ".".
+           }
+ 
+           DumperSupport::write_header(_writer, HPROF_UTF8, oopSize + len);
+           _writer->write_symbolID(reinterpret_cast<Symbol*>(_index));
+           // Write the string value.
+           // 1) super_names.
+           for (GrowableArrayIterator<Symbol*> it = super_names->begin(); it != super_names->end(); ++it) {
+             _writer->write_raw((*it)->bytes(), (*it)->utf8_length());
+             _writer->write_u1('.');
+           }
+           // 2) field name.
+           _writer->write_raw(fld.name()->bytes(), fld.name()->utf8_length());
+         }
+       }
+     }
+     super_names->pop();
+   }
+ 
+   void dump_inlined_field_names(Symbol* field_name, InlineKlass* field_klass) {
+     GrowableArray<Symbol*> super_names(4, mtServiceability);
+     dump_inlined_field_names(&super_names, field_name, field_klass);
+   }
+ 
+ public:
+   InlinedFieldNameDumper(AbstractDumpWriter* writer, InlinedObjects* owner, Callback callback)
+     : _writer(writer), _owner(owner), _callback(callback), _index(0)  {
+   }
+ 
+   void do_klass(Klass* k) {
+     if (!k->is_instance_klass()) {
+       return;
+     }
+     InstanceKlass* ik = InstanceKlass::cast(k);
+     // if (ik->has_inline_type_fields()) {
+     //   return;
+     // }
+ 
+     uintx base_index = _index;
+     int count = 0;
+ 
+     for (HierarchicalFieldStream<JavaFieldStream> fld(ik); !fld.done(); fld.next()) {
+       if (!fld.access_flags().is_static()) {
+         if (DumperSupport::is_inlined_field(fld.field_descriptor())) {
+           dump_inlined_field_names(fld.name(), DumperSupport::get_inlined_field_klass(fld.field_descriptor()));
+           count++;
+         }
+       }
+     }
+ 
+     if (count != 0) {
+       _callback(_owner, k, base_index, count);
+     }
+   }
+ };
+ 
+ class InlinedFieldsDumper : public LockedClassesDo {
+ private:
+   AbstractDumpWriter* _writer;
+ 
+ public:
+   InlinedFieldsDumper(AbstractDumpWriter* writer) : _writer(writer) {}
+ 
+   void do_klass(Klass* k) {
+     if (!k->is_instance_klass()) {
+       return;
+     }
+     InstanceKlass* ik = InstanceKlass::cast(k);
+     // if (ik->has_inline_type_fields()) {
+     //   return;
+     // }
+ 
+     // We can be at a point where java mirror does not exist yet.
+     // So we need to check that the class is at least loaded, to avoid crash from a null mirror.
+     if (!ik->is_loaded()) {
+       return;
+     }
+ 
+     u2 inlined_count = 0;
+     for (HierarchicalFieldStream<JavaFieldStream> fld(ik); !fld.done(); fld.next()) {
+       if (!fld.access_flags().is_static()) {
+         if (DumperSupport::is_inlined_field(fld.field_descriptor())) {
+           inlined_count++;
+         }
+       }
+     }
+     if (inlined_count != 0) {
+       _writer->write_u1(HPROF_CLASS_WITH_INLINED_FIELDS);
+ 
+       // class ID
+       _writer->write_classID(ik);
+       // number of inlined fields
+       _writer->write_u2(inlined_count);
+       u2 index = 0;
+       for (HierarchicalFieldStream<JavaFieldStream> fld(ik); !fld.done(); fld.next()) {
+         if (!fld.access_flags().is_static()) {
+           if (DumperSupport::is_inlined_field(fld.field_descriptor())) {
+             // inlined field index
+             _writer->write_u2(index);
+             // synthetic field count
+             u2 field_count = DumperSupport::get_instance_fields_count(DumperSupport::get_inlined_field_klass(fld.field_descriptor()));
+             _writer->write_u2(field_count);
+             // original field name
+             _writer->write_symbolID(fld.name());
+             // inlined field class ID
+             _writer->write_classID(DumperSupport::get_inlined_field_klass(fld.field_descriptor()));
+ 
+             index += field_count;
+           } else {
+             index++;
+           }
+         }
+       }
+     }
+   }
+ };
+ 
+ 
+ void InlinedObjects::init() {
+   _instance = this;
+ 
+   struct Closure : public SymbolClosure {
+     uintx _min_id = max_uintx;
+     uintx _max_id = 0;
+     Closure() : _min_id(max_uintx), _max_id(0) {}
+ 
+     void do_symbol(Symbol** p) {
+       uintx val = reinterpret_cast<uintx>(*p);
+       if (val < _min_id) {
+         _min_id = val;
+       }
+       if (val > _max_id) {
+         _max_id = val;
+       }
+     }
+   } closure;
+ 
+   SymbolTable::symbols_do(&closure);
+ 
+   _min_string_id = closure._min_id;
+   _max_string_id = closure._max_id;
+ }
+ 
+ void InlinedObjects::release() {
+   _instance = nullptr;
+ 
+   if (_inlined_field_map != nullptr) {
+     delete _inlined_field_map;
+     _inlined_field_map = nullptr;
+   }
+   if (_flat_arrays != nullptr) {
+     delete _flat_arrays;
+     _flat_arrays = nullptr;
+   }
+ }
+ 
+ void InlinedObjects::inlined_field_names_callback(InlinedObjects* _this, const Klass* klass, uintx base_index, int count) {
+   if (_this->_inlined_field_map == nullptr) {
+     _this->_inlined_field_map = new (mtServiceability) GrowableArray<ClassInlinedFields>(100, mtServiceability);
+   }
+   _this->_inlined_field_map->append(ClassInlinedFields(klass, base_index));
+ 
+   // counters for dumping classes with inlined fields
+   _this->_classes_count++;
+   _this->_inlined_fields_count += count;
+ }
+ 
+ void InlinedObjects::dump_inlined_field_names(AbstractDumpWriter* writer) {
+   InlinedFieldNameDumper nameDumper(writer, this, inlined_field_names_callback);
+   ClassLoaderDataGraph::classes_do(&nameDumper);
+ 
+   if (_inlined_field_map != nullptr) {
+     // prepare the map for  get_base_index_for().
+     _inlined_field_map->sort(ClassInlinedFields::compare);
+   }
+ }
+ 
+ uintx InlinedObjects::get_base_index_for(Klass* k) {
+   if (_inlined_field_map != nullptr) {
+     bool found = false;
+     int idx = _inlined_field_map->find_sorted<ClassInlinedFields, ClassInlinedFields::compare>(ClassInlinedFields(k, 0), found);
+     if (found) {
+         return _inlined_field_map->at(idx).base_index;
+     }
+   }
+ 
+   // return max_uintx, so get_next_string_id returns 0.
+   return max_uintx;
+ }
+ 
+ uintx InlinedObjects::get_next_string_id(uintx id) {
+   if (++id == _min_string_id) {
+     return _max_string_id + 1;
+   }
+   return id;
+ }
+ 
+ void InlinedObjects::dump_classed_with_inlined_fields(AbstractDumpWriter* writer) {
+   if (_classes_count != 0) {
+     // Record for each class contains tag(u1), class ID and count(u2)
+     // for each inlined field index(u2), synthetic fields count(u2), original field name and class ID
+     int size = _classes_count * (1 + sizeof(address) + 2)
+              + _inlined_fields_count * (2 + 2 + sizeof(address) + sizeof(address));
+     DumperSupport::write_header(writer, HPROF_INLINED_FIELDS, (u4)size);
+ 
+     InlinedFieldsDumper dumper(writer);
+     ClassLoaderDataGraph::classes_do(&dumper);
+   }
+ }
+ 
+ void InlinedObjects::add_flat_array(oop array) {
+   if (_flat_arrays == nullptr) {
+     _flat_arrays = new (mtServiceability) GrowableArray<oop>(100, mtServiceability);
+   }
+   _flat_arrays->append(array);
+ }
+ 
+ void InlinedObjects::dump_flat_arrays(AbstractDumpWriter* writer) {
+   if (_flat_arrays != nullptr) {
+     // For each flat array the record contains tag (u1), object ID and class ID.
+     int size = _flat_arrays->length() * (1 + sizeof(address) + sizeof(address));
+ 
+     DumperSupport::write_header(writer, HPROF_FLAT_ARRAYS, (u4)size);
+     for (GrowableArrayIterator<oop> it = _flat_arrays->begin(); it != _flat_arrays->end(); ++it) {
+       flatArrayOop array = flatArrayOop(*it);
+       FlatArrayKlass* array_klass = FlatArrayKlass::cast(array->klass());
+       InlineKlass* element_klass = array_klass->element_klass();
+       writer->write_u1(HPROF_FLAT_ARRAY);
+       writer->write_objectID(array);
+       writer->write_classID(element_klass);
+     }
+   }
+ }
+ 
+ 
  // Support class used to generate HPROF_UTF8 records from the entries in the
  // SymbolTable.
  
  class SymbolTableDumper : public SymbolClosure {
   private:

@@ -1896,10 +2397,12 @@
      // create a HPROF_GC_INSTANCE record for each object
      DumperSupport::dump_instance(writer(), o, &_class_cache);
    } else if (o->is_objArray()) {
      // create a HPROF_GC_OBJ_ARRAY_DUMP record for each object array
      DumperSupport::dump_object_array(writer(), objArrayOop(o));
+   } else if (o->is_flatArray()) {
+     DumperSupport::dump_flat_array(writer(), flatArrayOop(o), &_class_cache);
    } else if (o->is_typeArray()) {
      // create a HPROF_GC_PRIM_ARRAY_DUMP record for each type array
      DumperSupport::dump_prim_array(writer(), typeArrayOop(o));
    }
  }

@@ -1939,22 +2442,24 @@
  
  // DumpMerger merges separate dump files into a complete one
  class DumpMerger : public StackObj {
  private:
    DumpWriter* _writer;
+   InlinedObjects*  _inlined_objects;
    const char* _path;
    bool _has_error;
    int _dump_seq;
  
  private:
    void merge_file(char* path);
    void merge_done();
    void set_error(const char* msg);
  
  public:
-   DumpMerger(const char* path, DumpWriter* writer, int dump_seq) :
+   DumpMerger(const char* path, DumpWriter* writer, InlinedObjects* inlined_objects, int dump_seq) :
      _writer(writer),
+     _inlined_objects(inlined_objects),
      _path(path),
      _has_error(_writer->has_error()),
      _dump_seq(dump_seq) {}
  
    void do_merge();

@@ -1962,11 +2467,13 @@
  
  void DumpMerger::merge_done() {
    // Writes the HPROF_HEAP_DUMP_END record.
    if (!_has_error) {
      DumperSupport::end_of_dump(_writer);
+     _inlined_objects->dump_flat_arrays(_writer);
      _writer->flush();
+     _inlined_objects->release();
    }
    _dump_seq = 0; //reset
  }
  
  void DumpMerger::set_error(const char* msg) {

@@ -2101,10 +2608,14 @@
    int                     _thread_dumpers_count;
    volatile int            _thread_serial_num;
    volatile int            _frame_serial_num;
  
    volatile int            _dump_seq;
+ 
+   // Inlined object support.
+   InlinedObjects          _inlined_objects;
+ 
    // parallel heap dump support
    uint                    _num_dumper_threads;
    DumperController*       _dumper_controller;
    ParallelObjectIterator* _poi;
    // worker id of VMDumper thread.

@@ -2202,10 +2713,12 @@
    }
    int dump_seq()           { return _dump_seq; }
    bool is_parallel_dump()  { return _num_dumper_threads > 1; }
    bool can_parallel_dump(WorkerThreads* workers);
  
+   InlinedObjects* inlined_objects() { return &_inlined_objects; }
+ 
    VMOp_Type type() const { return VMOp_HeapDumper; }
    virtual bool doit_prologue();
    void doit();
    void work(uint worker_id);
  };

@@ -2399,10 +2912,17 @@
      writer()->write_u8(os::javaTimeMillis());
      // HPROF_UTF8 records
      SymbolTableDumper sym_dumper(writer());
      SymbolTable::symbols_do(&sym_dumper);
  
+     // HPROF_UTF8 records for inlined field names.
+     inlined_objects()->init();
+     inlined_objects()->dump_inlined_field_names(writer());
+ 
+     // HPROF_INLINED_FIELDS
+     inlined_objects()->dump_classed_with_inlined_fields(writer());
+ 
      // write HPROF_LOAD_CLASS records
      {
        LockedClassesDo locked_load_classes(&do_load_class);
        ClassLoaderDataGraph::classes_do(&locked_load_classes);
      }

@@ -2450,11 +2970,13 @@
      HeapObjectDumper obj_dumper(writer());
      Universe::heap()->object_iterate(&obj_dumper);
      writer()->finish_dump_segment();
      // Writes the HPROF_HEAP_DUMP_END record because merge does not happen in serial dump
      DumperSupport::end_of_dump(writer());
+     inlined_objects()->dump_flat_arrays(writer());
      writer()->flush();
+     inlined_objects()->release();
    } else {
      // == Parallel dump
      ResourceMark rm;
      TraceTime timer("Dump heap objects in parallel", TRACETIME_LOG(Info, heapdump));
      DumpWriter* local_writer = is_vm_dumper(worker_id) ? writer() : create_local_writer();

@@ -2569,11 +3091,11 @@
    //          This is done by VM_HeapDumper, which is performed within safepoint.
    //
    // Phase 2: Merge multiple heap files into one complete heap dump file.
    //          This is done by DumpMerger, which is performed outside safepoint
    if (dumper.is_parallel_dump()) {
-     DumpMerger merger(path, &writer, dumper.dump_seq());
+     DumpMerger merger(path, &writer, dumper.inlined_objects(), dumper.dump_seq());
      Thread* current_thread = Thread::current();
      if (current_thread->is_AttachListener_thread()) {
        // perform heapdump file merge operation in the current thread prevents us
        // from occupying the VM Thread, which in turn affects the occurrence of
        // GC and other VM operations.
< prev index next >