| /* |
| * Copyright (c) 2009, 2016, 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_STACK_INLINE_HPP |
| #define SHARE_VM_UTILITIES_STACK_INLINE_HPP |
| |
| #include "utilities/align.hpp" |
| #include "utilities/stack.hpp" |
| #include "utilities/copy.hpp" |
| |
| template <MEMFLAGS F> StackBase<F>::StackBase(size_t segment_size, size_t max_cache_size, |
| size_t max_size): |
| _seg_size(segment_size), |
| _max_cache_size(max_cache_size), |
| _max_size(adjust_max_size(max_size, segment_size)) |
| { |
| assert(_max_size % _seg_size == 0, "not a multiple"); |
| } |
| |
| template <MEMFLAGS F> size_t StackBase<F>::adjust_max_size(size_t max_size, size_t seg_size) |
| { |
| assert(seg_size > 0, "cannot be 0"); |
| assert(max_size >= seg_size || max_size == 0, "max_size too small"); |
| const size_t limit = max_uintx - (seg_size - 1); |
| if (max_size == 0 || max_size > limit) { |
| max_size = limit; |
| } |
| return (max_size + seg_size - 1) / seg_size * seg_size; |
| } |
| |
| template <class E, MEMFLAGS F> |
| Stack<E, F>::Stack(size_t segment_size, size_t max_cache_size, size_t max_size): |
| StackBase<F>(adjust_segment_size(segment_size), max_cache_size, max_size) |
| { |
| reset(true); |
| } |
| |
| template <class E, MEMFLAGS F> |
| void Stack<E, F>::push(E item) |
| { |
| assert(!is_full(), "pushing onto a full stack"); |
| if (this->_cur_seg_size == this->_seg_size) { |
| push_segment(); |
| } |
| this->_cur_seg[this->_cur_seg_size] = item; |
| ++this->_cur_seg_size; |
| } |
| |
| template <class E, MEMFLAGS F> |
| E Stack<E, F>::pop() |
| { |
| assert(!is_empty(), "popping from an empty stack"); |
| if (this->_cur_seg_size == 1) { |
| E tmp = _cur_seg[--this->_cur_seg_size]; |
| pop_segment(); |
| return tmp; |
| } |
| return this->_cur_seg[--this->_cur_seg_size]; |
| } |
| |
| template <class E, MEMFLAGS F> |
| void Stack<E, F>::clear(bool clear_cache) |
| { |
| free_segments(_cur_seg); |
| if (clear_cache) free_segments(_cache); |
| reset(clear_cache); |
| } |
| |
| template <class E, MEMFLAGS F> |
| size_t Stack<E, F>::adjust_segment_size(size_t seg_size) |
| { |
| const size_t elem_sz = sizeof(E); |
| const size_t ptr_sz = sizeof(E*); |
| assert(elem_sz % ptr_sz == 0 || ptr_sz % elem_sz == 0, "bad element size"); |
| if (elem_sz < ptr_sz) { |
| return align_up(seg_size * elem_sz, ptr_sz) / elem_sz; |
| } |
| return seg_size; |
| } |
| |
| template <class E, MEMFLAGS F> |
| size_t Stack<E, F>::link_offset() const |
| { |
| return align_up(this->_seg_size * sizeof(E), sizeof(E*)); |
| } |
| |
| template <class E, MEMFLAGS F> |
| size_t Stack<E, F>::segment_bytes() const |
| { |
| return link_offset() + sizeof(E*); |
| } |
| |
| template <class E, MEMFLAGS F> |
| E** Stack<E, F>::link_addr(E* seg) const |
| { |
| return (E**) ((char*)seg + link_offset()); |
| } |
| |
| template <class E, MEMFLAGS F> |
| E* Stack<E, F>::get_link(E* seg) const |
| { |
| return *link_addr(seg); |
| } |
| |
| template <class E, MEMFLAGS F> |
| E* Stack<E, F>::set_link(E* new_seg, E* old_seg) |
| { |
| *link_addr(new_seg) = old_seg; |
| return new_seg; |
| } |
| |
| template <class E, MEMFLAGS F> |
| E* Stack<E, F>::alloc(size_t bytes) |
| { |
| return (E*) NEW_C_HEAP_ARRAY(char, bytes, F); |
| } |
| |
| template <class E, MEMFLAGS F> |
| void Stack<E, F>::free(E* addr, size_t bytes) |
| { |
| FREE_C_HEAP_ARRAY(char, (char*) addr); |
| } |
| |
| // Stack is used by the GC code and in some hot paths a lot of the Stack |
| // code gets inlined. This is generally good, but when too much code has |
| // been inlined, no further inlining is allowed by GCC. Therefore we need |
| // to prevent parts of the slow path in Stack to be inlined to allow other |
| // code to be. |
| template <class E, MEMFLAGS F> |
| NOINLINE void Stack<E, F>::push_segment() |
| { |
| assert(this->_cur_seg_size == this->_seg_size, "current segment is not full"); |
| E* next; |
| if (this->_cache_size > 0) { |
| // Use a cached segment. |
| next = _cache; |
| _cache = get_link(_cache); |
| --this->_cache_size; |
| } else { |
| next = alloc(segment_bytes()); |
| DEBUG_ONLY(zap_segment(next, true);) |
| } |
| const bool at_empty_transition = is_empty(); |
| this->_cur_seg = set_link(next, _cur_seg); |
| this->_cur_seg_size = 0; |
| this->_full_seg_size += at_empty_transition ? 0 : this->_seg_size; |
| DEBUG_ONLY(verify(at_empty_transition);) |
| } |
| |
| template <class E, MEMFLAGS F> |
| void Stack<E, F>::pop_segment() |
| { |
| assert(this->_cur_seg_size == 0, "current segment is not empty"); |
| E* const prev = get_link(_cur_seg); |
| if (this->_cache_size < this->_max_cache_size) { |
| // Add the current segment to the cache. |
| DEBUG_ONLY(zap_segment(_cur_seg, false);) |
| _cache = set_link(_cur_seg, _cache); |
| ++this->_cache_size; |
| } else { |
| DEBUG_ONLY(zap_segment(_cur_seg, true);) |
| free(_cur_seg, segment_bytes()); |
| } |
| const bool at_empty_transition = prev == NULL; |
| this->_cur_seg = prev; |
| this->_cur_seg_size = this->_seg_size; |
| this->_full_seg_size -= at_empty_transition ? 0 : this->_seg_size; |
| DEBUG_ONLY(verify(at_empty_transition);) |
| } |
| |
| template <class E, MEMFLAGS F> |
| void Stack<E, F>::free_segments(E* seg) |
| { |
| const size_t bytes = segment_bytes(); |
| while (seg != NULL) { |
| E* const prev = get_link(seg); |
| free(seg, bytes); |
| seg = prev; |
| } |
| } |
| |
| template <class E, MEMFLAGS F> |
| void Stack<E, F>::reset(bool reset_cache) |
| { |
| this->_cur_seg_size = this->_seg_size; // So push() will alloc a new segment. |
| this->_full_seg_size = 0; |
| _cur_seg = NULL; |
| if (reset_cache) { |
| this->_cache_size = 0; |
| _cache = NULL; |
| } |
| } |
| |
| #ifdef ASSERT |
| template <class E, MEMFLAGS F> |
| void Stack<E, F>::verify(bool at_empty_transition) const |
| { |
| assert(size() <= this->max_size(), "stack exceeded bounds"); |
| assert(this->cache_size() <= this->max_cache_size(), "cache exceeded bounds"); |
| assert(this->_cur_seg_size <= this->segment_size(), "segment index exceeded bounds"); |
| |
| assert(this->_full_seg_size % this->_seg_size == 0, "not a multiple"); |
| assert(at_empty_transition || is_empty() == (size() == 0), "mismatch"); |
| assert((_cache == NULL) == (this->cache_size() == 0), "mismatch"); |
| |
| if (is_empty()) { |
| assert(this->_cur_seg_size == this->segment_size(), "sanity"); |
| } |
| } |
| |
| template <class E, MEMFLAGS F> |
| void Stack<E, F>::zap_segment(E* seg, bool zap_link_field) const |
| { |
| if (!ZapStackSegments) return; |
| const size_t zap_bytes = segment_bytes() - (zap_link_field ? 0 : sizeof(E*)); |
| Copy::fill_to_bytes(seg, zap_bytes, badStackSegVal); |
| } |
| #endif |
| |
| template <class E, MEMFLAGS F> |
| E* ResourceStack<E, F>::alloc(size_t bytes) |
| { |
| return (E*) resource_allocate_bytes(bytes); |
| } |
| |
| template <class E, MEMFLAGS F> |
| void ResourceStack<E, F>::free(E* addr, size_t bytes) |
| { |
| resource_free_bytes((char*) addr, bytes); |
| } |
| |
| template <class E, MEMFLAGS F> |
| void StackIterator<E, F>::sync() |
| { |
| _full_seg_size = _stack._full_seg_size; |
| _cur_seg_size = _stack._cur_seg_size; |
| _cur_seg = _stack._cur_seg; |
| } |
| |
| template <class E, MEMFLAGS F> |
| E* StackIterator<E, F>::next_addr() |
| { |
| assert(!is_empty(), "no items left"); |
| if (_cur_seg_size == 1) { |
| E* addr = _cur_seg; |
| _cur_seg = _stack.get_link(_cur_seg); |
| _cur_seg_size = _stack.segment_size(); |
| _full_seg_size -= _stack.segment_size(); |
| return addr; |
| } |
| return _cur_seg + --_cur_seg_size; |
| } |
| |
| #endif // SHARE_VM_UTILITIES_STACK_INLINE_HPP |