8049421: G1 Class Unloading after completing a concurrent mark cycle
Reviewed-by: tschatzl, ehelin, brutisso, coleenp, roland, iveresov
Contributed-by: stefan.karlsson@oracle.com, mikael.gerdin@oracle.com
/*
* Copyright (c) 2000, 2014, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*
*/
#ifndef SHARE_VM_UTILITIES_ARRAY_HPP
#define SHARE_VM_UTILITIES_ARRAY_HPP
#include "memory/allocation.hpp"
#include "memory/allocation.inline.hpp"
#include "memory/metaspace.hpp"
#include "runtime/orderAccess.hpp"
// correct linkage required to compile w/o warnings
// (must be on file level - cannot be local)
extern "C" { typedef int (*ftype)(const void*, const void*); }
class ResourceArray: public ResourceObj {
protected:
int _length; // the number of array elements
void* _data; // the array memory
#ifdef ASSERT
int _nesting; // the resource area nesting level
#endif
// creation
ResourceArray() {
_length = 0;
_data = NULL;
DEBUG_ONLY(init_nesting();)
// client may call initialize, at most once
}
ResourceArray(size_t esize, int length) {
DEBUG_ONLY(_data = NULL);
initialize(esize, length);
}
void initialize(size_t esize, int length) {
assert(length >= 0, "illegal length");
assert(StressRewriter || _data == NULL, "must be new object");
_length = length;
_data = resource_allocate_bytes(esize * length);
DEBUG_ONLY(init_nesting();)
}
#ifdef ASSERT
void init_nesting();
#endif
// helper functions
void sort (size_t esize, ftype f); // sort the array
void expand (size_t esize, int i, int& size);// expand the array to include slot i
void remove_at(size_t esize, int i); // remove the element in slot i
public:
// standard operations
int length() const { return _length; }
bool is_empty() const { return length() == 0; }
};
template <MEMFLAGS F>class CHeapArray: public CHeapObj<F> {
protected:
int _length; // the number of array elements
void* _data; // the array memory
// creation
CHeapArray() {
_length = 0;
_data = NULL;
}
CHeapArray(size_t esize, int length) {
assert(length >= 0, "illegal length");
_length = length;
_data = (void*) NEW_C_HEAP_ARRAY(char *, esize * length, F);
}
void initialize(size_t esize, int length) {
// In debug set array to 0?
}
#ifdef ASSERT
void init_nesting();
#endif
// helper functions
void sort (size_t esize, ftype f); // sort the array
void expand (size_t esize, int i, int& size);// expand the array to include slot i
void remove_at(size_t esize, int i); // remove the element in slot i
public:
// standard operations
int length() const { return _length; }
bool is_empty() const { return length() == 0; }
};
#define define_generic_array(array_name,element_type, base_class) \
class array_name: public base_class { \
protected: \
typedef element_type etype; \
enum { esize = sizeof(etype) }; \
\
void base_remove_at(size_t size, int i) { base_class::remove_at(size, i); } \
\
public: \
/* creation */ \
array_name() : base_class() {} \
explicit array_name(const int length) : base_class(esize, length) {} \
array_name(const int length, const etype fx) { initialize(length, fx); } \
void initialize(const int length) { base_class::initialize(esize, length); } \
void initialize(const int length, const etype fx) { \
initialize(length); \
for (int i = 0; i < length; i++) ((etype*)_data)[i] = fx; \
} \
\
/* standard operations */ \
etype& operator [] (const int i) const { \
assert(0 <= i && i < length(), "index out of bounds"); \
return ((etype*)_data)[i]; \
} \
\
int index_of(const etype x) const { \
int i = length(); \
while (i-- > 0 && ((etype*)_data)[i] != x) ; \
/* i < 0 || ((etype*)_data)_data[i] == x */ \
return i; \
} \
\
void sort(int f(etype*, etype*)) { base_class::sort(esize, (ftype)f); } \
bool contains(const etype x) const { return index_of(x) >= 0; } \
\
/* deprecated operations - for compatibility with GrowableArray only */ \
etype at(const int i) const { return (*this)[i]; } \
void at_put(const int i, const etype x) { (*this)[i] = x; } \
etype* adr_at(const int i) { return &(*this)[i]; } \
int find(const etype x) { return index_of(x); } \
}; \
#define define_array(array_name,element_type) \
define_generic_array(array_name, element_type, ResourceArray)
#define define_stack(stack_name,array_name) \
class stack_name: public array_name { \
protected: \
int _size; \
\
void grow(const int i, const etype fx) { \
assert(i >= length(), "index too small"); \
if (i >= size()) expand(esize, i, _size); \
for (int j = length(); j <= i; j++) ((etype*)_data)[j] = fx; \
_length = i+1; \
} \
\
public: \
/* creation */ \
stack_name() : array_name() { _size = 0; } \
stack_name(const int size) { initialize(size); } \
stack_name(const int size, const etype fx) { initialize(size, fx); } \
void initialize(const int size, const etype fx) { \
_size = size; \
array_name::initialize(size, fx); \
/* _length == size, allocation and size are the same */ \
} \
void initialize(const int size) { \
_size = size; \
array_name::initialize(size); \
_length = 0; /* reset length to zero; _size records the allocation */ \
} \
\
/* standard operations */ \
int size() const { return _size; } \
\
int push(const etype x) { \
int len = length(); \
if (len >= size()) expand(esize, len, _size); \
((etype*)_data)[len] = x; \
_length = len+1; \
return len; \
} \
\
etype pop() { \
assert(!is_empty(), "stack is empty"); \
return ((etype*)_data)[--_length]; \
} \
\
etype top() const { \
assert(!is_empty(), "stack is empty"); \
return ((etype*)_data)[length() - 1]; \
} \
\
void push_all(const stack_name* stack) { \
const int l = stack->length(); \
for (int i = 0; i < l; i++) push(((etype*)(stack->_data))[i]); \
} \
\
etype at_grow(const int i, const etype fx) { \
if (i >= length()) grow(i, fx); \
return ((etype*)_data)[i]; \
} \
\
void at_put_grow(const int i, const etype x, const etype fx) { \
if (i >= length()) grow(i, fx); \
((etype*)_data)[i] = x; \
} \
\
void truncate(const int length) { \
assert(0 <= length && length <= this->length(), "illegal length"); \
_length = length; \
} \
\
void remove_at(int i) { base_remove_at(esize, i); } \
void remove(etype x) { remove_at(index_of(x)); } \
\
/* inserts the given element before the element at index i */ \
void insert_before(const int i, const etype el) { \
int len = length(); \
int new_length = len + 1; \
if (new_length >= size()) expand(esize, new_length, _size); \
for (int j = len - 1; j >= i; j--) { \
((etype*)_data)[j + 1] = ((etype*)_data)[j]; \
} \
_length = new_length; \
at_put(i, el); \
} \
\
/* inserts contents of the given stack before the element at index i */ \
void insert_before(const int i, const stack_name *st) { \
if (st->length() == 0) return; \
int len = length(); \
int st_len = st->length(); \
int new_length = len + st_len; \
if (new_length >= size()) expand(esize, new_length, _size); \
int j; \
for (j = len - 1; j >= i; j--) { \
((etype*)_data)[j + st_len] = ((etype*)_data)[j]; \
} \
for (j = 0; j < st_len; j++) { \
((etype*)_data)[i + j] = ((etype*)st->_data)[j]; \
} \
_length = new_length; \
} \
\
/* deprecated operations - for compatibility with GrowableArray only */ \
int capacity() const { return size(); } \
void clear() { truncate(0); } \
void trunc_to(const int length) { truncate(length); } \
int append(const etype x) { return push(x); } \
void appendAll(const stack_name* stack) { push_all(stack); } \
etype last() const { return top(); } \
}; \
#define define_resource_list(element_type) \
define_generic_array(element_type##Array, element_type, ResourceArray) \
define_stack(element_type##List, element_type##Array)
#define define_resource_pointer_list(element_type) \
define_generic_array(element_type##Array, element_type *, ResourceArray) \
define_stack(element_type##List, element_type##Array)
#define define_c_heap_list(element_type) \
define_generic_array(element_type##Array, element_type, CHeapArray) \
define_stack(element_type##List, element_type##Array)
#define define_c_heap_pointer_list(element_type) \
define_generic_array(element_type##Array, element_type *, CHeapArray) \
define_stack(element_type##List, element_type##Array)
// Arrays for basic types
define_array(boolArray, bool) define_stack(boolStack, boolArray)
define_array(intArray , int ) define_stack(intStack , intArray )
// Array for metadata allocation
template <typename T>
class Array: public MetaspaceObj {
friend class MetadataFactory;
friend class VMStructs;
friend class MethodHandleCompiler; // special case
friend class WhiteBox;
protected:
int _length; // the number of array elements
T _data[1]; // the array memory
void initialize(int length) {
_length = length;
}
private:
// Turn off copy constructor and assignment operator.
Array(const Array<T>&);
void operator=(const Array<T>&);
void* operator new(size_t size, ClassLoaderData* loader_data, int length, bool read_only, TRAPS) throw() {
size_t word_size = Array::size(length);
return (void*) Metaspace::allocate(loader_data, word_size, read_only,
MetaspaceObj::array_type(sizeof(T)), CHECK_NULL);
}
static size_t byte_sizeof(int length) { return sizeof(Array<T>) + MAX2(length - 1, 0) * sizeof(T); }
// WhiteBox API helper.
static int bytes_to_length(size_t bytes) {
assert(is_size_aligned(bytes, BytesPerWord), "Must be, for now");
if (sizeof(Array<T>) >= bytes) {
return 0;
}
size_t left = bytes - sizeof(Array<T>);
assert(is_size_aligned(left, sizeof(T)), "Must be");
size_t elements = left / sizeof(T);
assert(elements <= (size_t)INT_MAX, err_msg("number of elements " SIZE_FORMAT "doesn't fit into an int.", elements));
int length = (int)elements;
assert((size_t)size(length) * BytesPerWord == bytes,
err_msg("Expected: " SIZE_FORMAT " got: " SIZE_FORMAT,
bytes, (size_t)size(length) * BytesPerWord));
return length;
}
explicit Array(int length) : _length(length) {
assert(length >= 0, "illegal length");
}
Array(int length, T init) : _length(length) {
assert(length >= 0, "illegal length");
for (int i = 0; i < length; i++) {
_data[i] = init;
}
}
public:
// standard operations
int length() const { return _length; }
T* data() { return _data; }
bool is_empty() const { return length() == 0; }
int index_of(const T& x) const {
int i = length();
while (i-- > 0 && _data[i] != x) ;
return i;
}
// sort the array.
bool contains(const T& x) const { return index_of(x) >= 0; }
T at(int i) const { assert(i >= 0 && i< _length, err_msg("oob: 0 <= %d < %d", i, _length)); return _data[i]; }
void at_put(const int i, const T& x) { assert(i >= 0 && i< _length, err_msg("oob: 0 <= %d < %d", i, _length)); _data[i] = x; }
T* adr_at(const int i) { assert(i >= 0 && i< _length, err_msg("oob: 0 <= %d < %d", i, _length)); return &_data[i]; }
int find(const T& x) { return index_of(x); }
T at_acquire(const int which) { return OrderAccess::load_acquire(adr_at(which)); }
void release_at_put(int which, T contents) { OrderAccess::release_store(adr_at(which), contents); }
static int size(int length) {
return align_size_up(byte_sizeof(length), BytesPerWord) / BytesPerWord;
}
int size() {
return size(_length);
}
static int length_offset_in_bytes() { return (int) (offset_of(Array<T>, _length)); }
// Note, this offset don't have to be wordSize aligned.
static int base_offset_in_bytes() { return (int) (offset_of(Array<T>, _data)); };
// FIXME: How to handle this?
void print_value_on(outputStream* st) const {
st->print("Array<T>(" INTPTR_FORMAT ")", p2i(this));
}
#ifndef PRODUCT
void print(outputStream* st) {
for (int i = 0; i< _length; i++) {
st->print_cr("%d: " INTPTR_FORMAT, i, (intptr_t)at(i));
}
}
void print() { print(tty); }
#endif // PRODUCT
};
#endif // SHARE_VM_UTILITIES_ARRAY_HPP