External/pugixml
8
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Eliminate redundant strlen calls during set_value/set

Browse Source 
Since we use manual integer conversion we know the length of the string.

This makes set_value(int) ~30% faster for 4-digit numbers.
This commit is contained in:
Arseny Kapoulkine 2015-09-20 00:24:07 -07:00
parent 5750b7cc19
commit 9c539f92ab
1 changed files with 19 additions and 16 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

35
src/pugixml.cpp
View File

@ -4541,25 +4541,24 @@ PUGI__NS_BEGIN
#endif
template <typename U>
PUGI__FN char_t* integer_to_string(char_t (&buf)[64], U value, bool negative)
PUGI__FN char_t* integer_to_string(char_t* begin, char_t* end, U value, bool negative)
{
char_t* end = buf + sizeof(buf) / sizeof(buf[0]) - 1;
char_t* result = end - 1;
U rest = negative ? 0 - value : value;
*end-- = 0;
do
{
*end-- = static_cast<char_t>('0' + (rest % 10));
*result-- = static_cast<char_t>('0' + (rest % 10));
rest /= 10;
}
while (rest);
assert(end >= buf);
assert(result >= begin);
(void)begin;
*end = '-';
*result = '-';
return end + !negative;
return result + !negative;
}
// set value with conversion functions
@ -4580,18 +4579,20 @@ PUGI__NS_BEGIN
PUGI__FN bool set_value_convert(String& dest, Header& header, uintptr_t header_mask, int value)
{
char_t buf[64];
char_t* begin = integer_to_string<unsigned int>(buf, value, value < 0);
char_t* end = buf + sizeof(buf) / sizeof(buf[0]);
char_t* begin = integer_to_string<unsigned int>(buf, end, value, value < 0);
return strcpy_insitu(dest, header, header_mask, begin, strlength(begin));
return strcpy_insitu(dest, header, header_mask, begin, end - begin);
}
template <typename String, typename Header>
PUGI__FN bool set_value_convert(String& dest, Header& header, uintptr_t header_mask, unsigned int value)
{
char_t buf[64];
char_t* begin = integer_to_string<unsigned int>(buf, value, false);
char_t* end = buf + sizeof(buf) / sizeof(buf[0]);
char_t* begin = integer_to_string<unsigned int>(buf, end, value, false);
return strcpy_insitu(dest, header, header_mask, begin, strlength(begin));
return strcpy_insitu(dest, header, header_mask, begin, end - begin);
}
template <typename String, typename Header>
@ -4623,18 +4624,20 @@ PUGI__NS_BEGIN
PUGI__FN bool set_value_convert(String& dest, Header& header, uintptr_t header_mask, long long value)
{
char_t buf[64];
char_t* begin = integer_to_string<unsigned long long>(buf, value, value < 0);
char_t* end = buf + sizeof(buf) / sizeof(buf[0]);
char_t* begin = integer_to_string<unsigned long long>(buf, end, value, value < 0);
return strcpy_insitu(dest, header, header_mask, begin, strlength(begin));
return strcpy_insitu(dest, header, header_mask, begin, end - begin);
}
template <typename String, typename Header>
PUGI__FN bool set_value_convert(String& dest, Header& header, uintptr_t header_mask, unsigned long long value)
{
char_t buf[64];
char_t* begin = integer_to_string<unsigned long long>(buf, value, false);
char_t* end = buf + sizeof(buf) / sizeof(buf[0]);
char_t* begin = integer_to_string<unsigned long long>(buf, end, value, false);
return strcpy_insitu(dest, header, header_mask, begin, strlength(begin));
return strcpy_insitu(dest, header, header_mask, begin, end - begin);
}
#endif