From 628197f8c8d54c6ed3260ee4a2fe6b92b281aa0e Mon Sep 17 00:00:00 2001 From: "arseny.kapoulkine" Date: Mon, 13 Sep 2010 20:34:53 +0000 Subject: XPath: Minor speed/memory improvements git-svn-id: http://pugixml.googlecode.com/svn/trunk@726 99668b35-9821-0410-8761-19e4c4f06640 --- src/pugixml.cpp | 85 +++++++++++++++++++++++++++++++++------------------------ 1 file changed, 49 insertions(+), 36 deletions(-) (limited to 'src') diff --git a/src/pugixml.cpp b/src/pugixml.cpp index 3e32217..1303939 100644 --- a/src/pugixml.cpp +++ b/src/pugixml.cpp @@ -4787,19 +4787,24 @@ namespace pugi void* reallocate(void* ptr, size_t old_size, size_t new_size) { + // align size so that we're able to store pointers in subsequent blocks + old_size = (old_size + sizeof(void*) - 1) & ~(sizeof(void*) - 1); + new_size = (new_size + sizeof(void*) - 1) & ~(sizeof(void*) - 1); + // we can only reallocate the last object - assert(static_cast(ptr) + old_size == _root->data + _root_size); + assert(ptr == 0 || static_cast(ptr) + old_size == _root->data + _root_size); // adjust root size so that we have not allocated the object at all - _root_size -= old_size; - bool only_object = (_root_size == 0); + bool only_object = (_root_size == old_size); + + if (ptr) _root_size -= old_size; // allocate a new version (this will obviously reuse the memory if possible) void* result = allocate(new_size); if (!result) return 0; // $$ out of memory // we have a new block - if (result != ptr) + if (result != ptr && ptr) { // copy old data assert(new_size > old_size); @@ -4975,12 +4980,13 @@ namespace size_t length = target_length + source_length; // allocate new buffer - char_t* result = static_cast(alloc->allocate((length + 1) * sizeof(char_t))); + char_t* result = static_cast(alloc->reallocate(_uses_heap ? const_cast(_buffer) : 0, (target_length + 1) * sizeof(char_t), (length + 1) * sizeof(char_t))); if (!result) return; // $$ out of memory - // $$ reallocate - // append both strings in the new buffer - memcpy(result, _buffer, target_length * sizeof(char_t)); + // append first string to the new buffer in case there was no reallocation + if (!_uses_heap) memcpy(result, _buffer, target_length * sizeof(char_t)); + + // append second string to the new buffer memcpy(result + target_length, o._buffer, source_length * sizeof(char_t)); result[length] = 0; @@ -5874,21 +5880,8 @@ namespace size_t new_capacity = capacity + capacity / 2 + 1; // reallocate the old array or allocate a new one - xpath_node* data = 0; - - if (_begin) - { - data = static_cast(alloc->reallocate(_begin, capacity * sizeof(xpath_node), new_capacity * sizeof(xpath_node))); - if (!data) return; // $$ out of memory - } - else - { - data = static_cast(alloc->allocate(new_capacity * sizeof(xpath_node))); - if (!data) return; // $$ out of memory - - memcpy(data, _begin, capacity * sizeof(xpath_node)); - } - + xpath_node* data = static_cast(alloc->reallocate(_begin, capacity * sizeof(xpath_node), new_capacity * sizeof(xpath_node))); + if (!data) return; // $$ out of memory // finalize _begin = data; @@ -5899,6 +5892,28 @@ namespace *_end++ = node; } + void append(const xpath_node* begin, const xpath_node* end, xpath_allocator* alloc) + { + size_t size = static_cast(_end - _begin); + size_t capacity = static_cast(_eos - _begin); + size_t count = static_cast(end - begin); + + if (size + count > capacity) + { + // reallocate the old array or allocate a new one + xpath_node* data = static_cast(alloc->reallocate(_begin, capacity * sizeof(xpath_node), (size + count) * sizeof(xpath_node))); + if (!data) return; // $$ out of memory + + // finalize + _begin = data; + _end = data + size; + _eos = data + size + count; + } + + memcpy(_end, begin, count * sizeof(xpath_node)); + _end += count; + } + void sort() { _type = xpath_sort(_begin, _end, _type, false); @@ -7419,7 +7434,11 @@ namespace pugi xpath_node_set_raw ns = _left->eval_node_set(c, stack); for (const xpath_node* it = ns.begin(); it != ns.end(); ++it) + { + xpath_allocator_capture cri(stack.result); + r += convert_string_to_number(string_value(*it, stack.result).c_str()); + } return r; } @@ -7488,7 +7507,7 @@ namespace pugi xpath_allocator_capture ct(stack.temp); // count the string number - unsigned int count = 1; + size_t count = 1; for (xpath_ast_node* nc = _right; nc; nc = nc->_next) count++; // gather all strings @@ -7513,7 +7532,7 @@ namespace pugi // get total length size_t length = 0; - for (unsigned int i = 0; i < count; ++i) length += buffer[i].length(); + for (size_t i = 0; i < count; ++i) length += buffer[i].length(); // create final string char_t* result = static_cast(stack.result->allocate((length + 1) * sizeof(char_t))); @@ -7522,7 +7541,7 @@ namespace pugi { char_t* ri = result; - for (unsigned int i = 0; i < count; ++i) + for (size_t i = 0; i < count; ++i) for (const char_t* bi = buffer[i].c_str(); *bi; ++bi) *ri++ = *bi; @@ -7677,11 +7696,9 @@ namespace pugi assert(1 <= pos && pos <= end && end <= s_length + 1); const char_t* rbegin = s.c_str() + (pos - 1); + const char_t* rend = s.c_str() + (end - 1); - if (end == s_length + 1) - return s.uses_heap() ? xpath_string(rbegin, stack.result) : xpath_string_const(rbegin); - else - return xpath_string(s.c_str() + (pos - 1), s.c_str() + (end - 1), stack.result); + return (end == s_length + 1 && !s.uses_heap()) ? xpath_string_const(rbegin) : xpath_string(rbegin, rend, stack.result); } case ast_func_normalize_space_0: @@ -7771,9 +7788,7 @@ namespace pugi // we can optimize merging two sorted sets, but this is a very rare operation, so don't bother rs.set_type(xpath_node_set::type_unsorted); - for (const xpath_node* li = ls.begin(); li != ls.end(); ++li) - rs.push_back(*li, stack.result); - + rs.append(ls.begin(), ls.end(), stack.result); rs.remove_duplicates(); return rs; @@ -7866,9 +7881,7 @@ namespace pugi xpath_node_set_raw ns; ns.set_type(s.type()); - - for (xpath_node_set::const_iterator i = s.begin(); i != s.end(); ++i) - ns.push_back(*i, stack.result); + ns.append(s.begin(), s.end(), stack.result); return ns; } -- cgit v1.2.3