aoqi@0: /*
aoqi@0:  * Copyright (c) 2009, 2012, Oracle and/or its affiliates. All rights reserved.
aoqi@0:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
aoqi@0:  *
aoqi@0:  * This code is free software; you can redistribute it and/or modify it
aoqi@0:  * under the terms of the GNU General Public License version 2 only, as
aoqi@0:  * published by the Free Software Foundation.
aoqi@0:  *
aoqi@0:  * This code is distributed in the hope that it will be useful, but WITHOUT
aoqi@0:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
aoqi@0:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
aoqi@0:  * version 2 for more details (a copy is included in the LICENSE file that
aoqi@0:  * accompanied this code).
aoqi@0:  *
aoqi@0:  * You should have received a copy of the GNU General Public License version
aoqi@0:  * 2 along with this work; if not, write to the Free Software Foundation,
aoqi@0:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
aoqi@0:  *
aoqi@0:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
aoqi@0:  * or visit www.oracle.com if you need additional information or have any
aoqi@0:  * questions.
aoqi@0:  *
aoqi@0:  */
aoqi@0: 
aoqi@0: #ifndef SHARE_VM_UTILITIES_STACK_INLINE_HPP
aoqi@0: #define SHARE_VM_UTILITIES_STACK_INLINE_HPP
aoqi@0: 
aoqi@0: #include "utilities/stack.hpp"
aoqi@0: 
aoqi@0: template <MEMFLAGS F> StackBase<F>::StackBase(size_t segment_size, size_t max_cache_size,
aoqi@0:                      size_t max_size):
aoqi@0:   _seg_size(segment_size),
aoqi@0:   _max_cache_size(max_cache_size),
aoqi@0:   _max_size(adjust_max_size(max_size, segment_size))
aoqi@0: {
aoqi@0:   assert(_max_size % _seg_size == 0, "not a multiple");
aoqi@0: }
aoqi@0: 
aoqi@0: template <MEMFLAGS F> size_t StackBase<F>::adjust_max_size(size_t max_size, size_t seg_size)
aoqi@0: {
aoqi@0:   assert(seg_size > 0, "cannot be 0");
aoqi@0:   assert(max_size >= seg_size || max_size == 0, "max_size too small");
aoqi@0:   const size_t limit = max_uintx - (seg_size - 1);
aoqi@0:   if (max_size == 0 || max_size > limit) {
aoqi@0:     max_size = limit;
aoqi@0:   }
aoqi@0:   return (max_size + seg_size - 1) / seg_size * seg_size;
aoqi@0: }
aoqi@0: 
aoqi@0: template <class E, MEMFLAGS F>
aoqi@0: Stack<E, F>::Stack(size_t segment_size, size_t max_cache_size, size_t max_size):
aoqi@0:   StackBase<F>(adjust_segment_size(segment_size), max_cache_size, max_size)
aoqi@0: {
aoqi@0:   reset(true);
aoqi@0: }
aoqi@0: 
aoqi@0: template <class E, MEMFLAGS F>
aoqi@0: void Stack<E, F>::push(E item)
aoqi@0: {
aoqi@0:   assert(!is_full(), "pushing onto a full stack");
aoqi@0:   if (this->_cur_seg_size == this->_seg_size) {
aoqi@0:     push_segment();
aoqi@0:   }
aoqi@0:   this->_cur_seg[this->_cur_seg_size] = item;
aoqi@0:   ++this->_cur_seg_size;
aoqi@0: }
aoqi@0: 
aoqi@0: template <class E, MEMFLAGS F>
aoqi@0: E Stack<E, F>::pop()
aoqi@0: {
aoqi@0:   assert(!is_empty(), "popping from an empty stack");
aoqi@0:   if (this->_cur_seg_size == 1) {
aoqi@0:     E tmp = _cur_seg[--this->_cur_seg_size];
aoqi@0:     pop_segment();
aoqi@0:     return tmp;
aoqi@0:   }
aoqi@0:   return this->_cur_seg[--this->_cur_seg_size];
aoqi@0: }
aoqi@0: 
aoqi@0: template <class E, MEMFLAGS F>
aoqi@0: void Stack<E, F>::clear(bool clear_cache)
aoqi@0: {
aoqi@0:   free_segments(_cur_seg);
aoqi@0:   if (clear_cache) free_segments(_cache);
aoqi@0:   reset(clear_cache);
aoqi@0: }
aoqi@0: 
aoqi@0: template <class E, MEMFLAGS F>
aoqi@0: size_t Stack<E, F>::default_segment_size()
aoqi@0: {
aoqi@0:   // Number of elements that fit in 4K bytes minus the size of two pointers
aoqi@0:   // (link field and malloc header).
aoqi@0:   return (4096 - 2 * sizeof(E*)) / sizeof(E);
aoqi@0: }
aoqi@0: 
aoqi@0: template <class E, MEMFLAGS F>
aoqi@0: size_t Stack<E, F>::adjust_segment_size(size_t seg_size)
aoqi@0: {
aoqi@0:   const size_t elem_sz = sizeof(E);
aoqi@0:   const size_t ptr_sz = sizeof(E*);
aoqi@0:   assert(elem_sz % ptr_sz == 0 || ptr_sz % elem_sz == 0, "bad element size");
aoqi@0:   if (elem_sz < ptr_sz) {
aoqi@0:     return align_size_up(seg_size * elem_sz, ptr_sz) / elem_sz;
aoqi@0:   }
aoqi@0:   return seg_size;
aoqi@0: }
aoqi@0: 
aoqi@0: template <class E, MEMFLAGS F>
aoqi@0: size_t Stack<E, F>::link_offset() const
aoqi@0: {
aoqi@0:   return align_size_up(this->_seg_size * sizeof(E), sizeof(E*));
aoqi@0: }
aoqi@0: 
aoqi@0: template <class E, MEMFLAGS F>
aoqi@0: size_t Stack<E, F>::segment_bytes() const
aoqi@0: {
aoqi@0:   return link_offset() + sizeof(E*);
aoqi@0: }
aoqi@0: 
aoqi@0: template <class E, MEMFLAGS F>
aoqi@0: E** Stack<E, F>::link_addr(E* seg) const
aoqi@0: {
aoqi@0:   return (E**) ((char*)seg + link_offset());
aoqi@0: }
aoqi@0: 
aoqi@0: template <class E, MEMFLAGS F>
aoqi@0: E* Stack<E, F>::get_link(E* seg) const
aoqi@0: {
aoqi@0:   return *link_addr(seg);
aoqi@0: }
aoqi@0: 
aoqi@0: template <class E, MEMFLAGS F>
aoqi@0: E* Stack<E, F>::set_link(E* new_seg, E* old_seg)
aoqi@0: {
aoqi@0:   *link_addr(new_seg) = old_seg;
aoqi@0:   return new_seg;
aoqi@0: }
aoqi@0: 
aoqi@0: template <class E, MEMFLAGS F>
aoqi@0: E* Stack<E, F>::alloc(size_t bytes)
aoqi@0: {
aoqi@0:   return (E*) NEW_C_HEAP_ARRAY(char, bytes, F);
aoqi@0: }
aoqi@0: 
aoqi@0: template <class E, MEMFLAGS F>
aoqi@0: void Stack<E, F>::free(E* addr, size_t bytes)
aoqi@0: {
aoqi@0:   FREE_C_HEAP_ARRAY(char, (char*) addr, F);
aoqi@0: }
aoqi@0: 
aoqi@0: template <class E, MEMFLAGS F>
aoqi@0: void Stack<E, F>::push_segment()
aoqi@0: {
aoqi@0:   assert(this->_cur_seg_size == this->_seg_size, "current segment is not full");
aoqi@0:   E* next;
aoqi@0:   if (this->_cache_size > 0) {
aoqi@0:     // Use a cached segment.
aoqi@0:     next = _cache;
aoqi@0:     _cache = get_link(_cache);
aoqi@0:     --this->_cache_size;
aoqi@0:   } else {
aoqi@0:     next = alloc(segment_bytes());
aoqi@0:     DEBUG_ONLY(zap_segment(next, true);)
aoqi@0:   }
aoqi@0:   const bool at_empty_transition = is_empty();
aoqi@0:   this->_cur_seg = set_link(next, _cur_seg);
aoqi@0:   this->_cur_seg_size = 0;
aoqi@0:   this->_full_seg_size += at_empty_transition ? 0 : this->_seg_size;
aoqi@0:   DEBUG_ONLY(verify(at_empty_transition);)
aoqi@0: }
aoqi@0: 
aoqi@0: template <class E, MEMFLAGS F>
aoqi@0: void Stack<E, F>::pop_segment()
aoqi@0: {
aoqi@0:   assert(this->_cur_seg_size == 0, "current segment is not empty");
aoqi@0:   E* const prev = get_link(_cur_seg);
aoqi@0:   if (this->_cache_size < this->_max_cache_size) {
aoqi@0:     // Add the current segment to the cache.
aoqi@0:     DEBUG_ONLY(zap_segment(_cur_seg, false);)
aoqi@0:     _cache = set_link(_cur_seg, _cache);
aoqi@0:     ++this->_cache_size;
aoqi@0:   } else {
aoqi@0:     DEBUG_ONLY(zap_segment(_cur_seg, true);)
aoqi@0:     free(_cur_seg, segment_bytes());
aoqi@0:   }
aoqi@0:   const bool at_empty_transition = prev == NULL;
aoqi@0:   this->_cur_seg = prev;
aoqi@0:   this->_cur_seg_size = this->_seg_size;
aoqi@0:   this->_full_seg_size -= at_empty_transition ? 0 : this->_seg_size;
aoqi@0:   DEBUG_ONLY(verify(at_empty_transition);)
aoqi@0: }
aoqi@0: 
aoqi@0: template <class E, MEMFLAGS F>
aoqi@0: void Stack<E, F>::free_segments(E* seg)
aoqi@0: {
aoqi@0:   const size_t bytes = segment_bytes();
aoqi@0:   while (seg != NULL) {
aoqi@0:     E* const prev = get_link(seg);
aoqi@0:     free(seg, bytes);
aoqi@0:     seg = prev;
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: template <class E, MEMFLAGS F>
aoqi@0: void Stack<E, F>::reset(bool reset_cache)
aoqi@0: {
aoqi@0:   this->_cur_seg_size = this->_seg_size; // So push() will alloc a new segment.
aoqi@0:   this->_full_seg_size = 0;
aoqi@0:   _cur_seg = NULL;
aoqi@0:   if (reset_cache) {
aoqi@0:     this->_cache_size = 0;
aoqi@0:     _cache = NULL;
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: #ifdef ASSERT
aoqi@0: template <class E, MEMFLAGS F>
aoqi@0: void Stack<E, F>::verify(bool at_empty_transition) const
aoqi@0: {
aoqi@0:   assert(size() <= this->max_size(), "stack exceeded bounds");
aoqi@0:   assert(this->cache_size() <= this->max_cache_size(), "cache exceeded bounds");
aoqi@0:   assert(this->_cur_seg_size <= this->segment_size(), "segment index exceeded bounds");
aoqi@0: 
aoqi@0:   assert(this->_full_seg_size % this->_seg_size == 0, "not a multiple");
aoqi@0:   assert(at_empty_transition || is_empty() == (size() == 0), "mismatch");
aoqi@0:   assert((_cache == NULL) == (this->cache_size() == 0), "mismatch");
aoqi@0: 
aoqi@0:   if (is_empty()) {
aoqi@0:     assert(this->_cur_seg_size == this->segment_size(), "sanity");
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: template <class E, MEMFLAGS F>
aoqi@0: void Stack<E, F>::zap_segment(E* seg, bool zap_link_field) const
aoqi@0: {
aoqi@0:   if (!ZapStackSegments) return;
aoqi@0:   const size_t zap_bytes = segment_bytes() - (zap_link_field ? 0 : sizeof(E*));
aoqi@0:   uint32_t* cur = (uint32_t*)seg;
aoqi@0:   const uint32_t* end = cur + zap_bytes / sizeof(uint32_t);
aoqi@0:   while (cur < end) {
aoqi@0:     *cur++ = 0xfadfaded;
aoqi@0:   }
aoqi@0: }
aoqi@0: #endif
aoqi@0: 
aoqi@0: template <class E, MEMFLAGS F>
aoqi@0: E* ResourceStack<E, F>::alloc(size_t bytes)
aoqi@0: {
aoqi@0:   return (E*) resource_allocate_bytes(bytes);
aoqi@0: }
aoqi@0: 
aoqi@0: template <class E, MEMFLAGS F>
aoqi@0: void ResourceStack<E, F>::free(E* addr, size_t bytes)
aoqi@0: {
aoqi@0:   resource_free_bytes((char*) addr, bytes);
aoqi@0: }
aoqi@0: 
aoqi@0: template <class E, MEMFLAGS F>
aoqi@0: void StackIterator<E, F>::sync()
aoqi@0: {
aoqi@0:   _full_seg_size = _stack._full_seg_size;
aoqi@0:   _cur_seg_size = _stack._cur_seg_size;
aoqi@0:   _cur_seg = _stack._cur_seg;
aoqi@0: }
aoqi@0: 
aoqi@0: template <class E, MEMFLAGS F>
aoqi@0: E* StackIterator<E, F>::next_addr()
aoqi@0: {
aoqi@0:   assert(!is_empty(), "no items left");
aoqi@0:   if (_cur_seg_size == 1) {
aoqi@0:     E* addr = _cur_seg;
aoqi@0:     _cur_seg = _stack.get_link(_cur_seg);
aoqi@0:     _cur_seg_size = _stack.segment_size();
aoqi@0:     _full_seg_size -= _stack.segment_size();
aoqi@0:     return addr;
aoqi@0:   }
aoqi@0:   return _cur_seg + --_cur_seg_size;
aoqi@0: }
aoqi@0: 
aoqi@0: #endif // SHARE_VM_UTILITIES_STACK_INLINE_HPP