From ec050e08a420558bc5d81c75246f478e606ea8f2 Mon Sep 17 00:00:00 2001
From: Arseny Kapoulkine <arseny.kapoulkine@gmail.com>
Date: Wed, 24 Sep 2014 05:22:26 +0000
Subject: [PATCH] Optimize xml_buffered_writer::write(const char_t*)
Instead of computing the length and doing memcpy we now copy the head of
the string into the buffer (like strcpy) and then use memcpy for tail if
necessary. This results in 10-15% speedup for writing typical documents with
a mix of short and long strings.
git-svn-id: https://pugixml.googlecode.com/svn/trunk@1023 99668b35-9821-0410-8761-19e4c4f06640
---
src/pugixml.cpp | 33 ++++++++++++++++++++++++++++-----
1 file changed, 28 insertions(+), 5 deletions(-)
diff --git a/src/pugixml.cpp b/src/pugixml.cpp
index 18c89e21..b9eab78a 100644
--- a/src/pugixml.cpp
+++ b/src/pugixml.cpp
@@ -2888,7 +2888,7 @@ PUGI__NS_BEGIN
#ifdef PUGIXML_WCHAR_MODE
PUGI__FN size_t get_valid_length(const char_t* data, size_t length)
{
- assert(length > 0);
+ if (length < 1) return 0;
// discard last character if it's the lead of a surrogate pair
return (sizeof(wchar_t) == 2 && static_cast<unsigned int>(static_cast<uint16_t>(data[length - 1]) - 0xD800) < 0x400) ? length - 1 : length;
@@ -2960,7 +2960,7 @@ PUGI__NS_BEGIN
#else
PUGI__FN size_t get_valid_length(const char_t* data, size_t length)
{
- assert(length > 4);
+ if (length < 5) return 0;
for (size_t i = 1; i <= 4; ++i)
{
@@ -3080,6 +3080,7 @@ PUGI__NS_BEGIN
// get chunk size by selecting such number of characters that are guaranteed to fit into scratch buffer
// and form a complete codepoint sequence (i.e. discard start of last codepoint if necessary)
size_t chunk_size = get_valid_length(data, bufcapacity);
+ assert(chunk_size);
// convert chunk and write
flush(data, chunk_size);
@@ -3112,7 +3113,27 @@ PUGI__NS_BEGIN
void write(const char_t* data)
{
- write(data, strlength(data));
+ // write the part of the string that fits in the buffer
+ size_t offset = bufsize;
+
+ while (*data && offset < bufcapacity)
+ buffer[offset++] = *data++;
+
+ // write the rest
+ if (offset < bufcapacity)
+ {
+ bufsize = offset;
+ }
+ else
+ {
+ // backtrack a bit if we have split the codepoint
+ size_t length = offset - bufsize;
+ size_t extra = length - get_valid_length(data - length, length);
+
+ bufsize = offset - extra;
+
+ write_direct(data - extra, strlength(data) + extra);
+ }
}
void write(char_t d0)
@@ -8265,7 +8286,8 @@ PUGI__NS_BEGIN
switch (_test)
{
case nodetest_name:
- if (strequal(name, _data.nodetest)) ns.push_back(xpath_node(a, parent), alloc);
+ if (strequal(name, _data.nodetest))
+ ns.push_back(xpath_node(a, parent), alloc);
break;
case nodetest_type_node:
@@ -8290,7 +8312,8 @@ PUGI__NS_BEGIN
switch (_test)
{
case nodetest_name:
- if (n.type() == node_element && strequal(n.name(), _data.nodetest)) ns.push_back(n, alloc);
+ if (n.type() == node_element && strequal(n.name(), _data.nodetest))
+ ns.push_back(n, alloc);
break;
case nodetest_type_node:
--
GitLab