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Inline basic UTF-8 functions.

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Shows a measurable speedup when processing UTF-8 data, such as with
the new builtin collation provider.

Discussion: https://postgr.es/m/163f4e2190cdf67f67016044e503c5004547e5a9.camel@j-davis.com
Reviewed-by: Peter Eisentraut
This commit is contained in:
Jeff Davis 2024-03-20 09:40:57 -07:00
parent 2b520860c0
commit 9acae56ce0
2 changed files with 61 additions and 61 deletions
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61
src/common/wchar.c
View File

@ -476,39 +476,6 @@ pg_utf2wchar_with_len(const unsigned char *from, pg_wchar *to, int len)
}
/*
* Map a Unicode code point to UTF-8. utf8string must have at least
* unicode_utf8len(c) bytes available.
*/
unsigned char *
unicode_to_utf8(pg_wchar c, unsigned char *utf8string)
{
if (c <= 0x7F)
{
utf8string[0] = c;
}
else if (c <= 0x7FF)
{
utf8string[0] = 0xC0 | ((c >> 6) & 0x1F);
utf8string[1] = 0x80 | (c & 0x3F);
}
else if (c <= 0xFFFF)
{
utf8string[0] = 0xE0 | ((c >> 12) & 0x0F);
utf8string[1] = 0x80 | ((c >> 6) & 0x3F);
utf8string[2] = 0x80 | (c & 0x3F);
}
else
{
utf8string[0] = 0xF0 | ((c >> 18) & 0x07);
utf8string[1] = 0x80 | ((c >> 12) & 0x3F);
utf8string[2] = 0x80 | ((c >> 6) & 0x3F);
utf8string[3] = 0x80 | (c & 0x3F);
}
return utf8string;
}
/*
* Trivial conversion from pg_wchar to UTF-8.
* caller should allocate enough space for "to"
@ -670,34 +637,6 @@ ucs_wcwidth(pg_wchar ucs)
return 1;
}
/*
* Convert a UTF-8 character to a Unicode code point.
* This is a one-character version of pg_utf2wchar_with_len.
*
* No error checks here, c must point to a long-enough string.
*/
pg_wchar
utf8_to_unicode(const unsigned char *c)
{
if ((*c & 0x80) == 0)
return (pg_wchar) c[0];
else if ((*c & 0xe0) == 0xc0)
return (pg_wchar) (((c[0] & 0x1f) << 6) |
(c[1] & 0x3f));
else if ((*c & 0xf0) == 0xe0)
return (pg_wchar) (((c[0] & 0x0f) << 12) |
((c[1] & 0x3f) << 6) |
(c[2] & 0x3f));
else if ((*c & 0xf8) == 0xf0)
return (pg_wchar) (((c[0] & 0x07) << 18) |
((c[1] & 0x3f) << 12) |
((c[2] & 0x3f) << 6) |
(c[3] & 0x3f));
else
/* that is an invalid code on purpose */
return 0xffffffff;
}
static int
pg_utf_dsplen(const unsigned char *s)
{

61
src/include/mb/pg_wchar.h
View File

@ -555,6 +555,67 @@ surrogate_pair_to_codepoint(pg_wchar first, pg_wchar second)
return ((first & 0x3FF) << 10) + 0x10000 + (second & 0x3FF);
}
/*
* Convert a UTF-8 character to a Unicode code point.
* This is a one-character version of pg_utf2wchar_with_len.
*
* No error checks here, c must point to a long-enough string.
*/
static inline pg_wchar
utf8_to_unicode(const unsigned char *c)
{
if ((*c & 0x80) == 0)
return (pg_wchar) c[0];
else if ((*c & 0xe0) == 0xc0)
return (pg_wchar) (((c[0] & 0x1f) << 6) |
(c[1] & 0x3f));
else if ((*c & 0xf0) == 0xe0)
return (pg_wchar) (((c[0] & 0x0f) << 12) |
((c[1] & 0x3f) << 6) |
(c[2] & 0x3f));
else if ((*c & 0xf8) == 0xf0)
return (pg_wchar) (((c[0] & 0x07) << 18) |
((c[1] & 0x3f) << 12) |
((c[2] & 0x3f) << 6) |
(c[3] & 0x3f));
else
/* that is an invalid code on purpose */
return 0xffffffff;
}
/*
* Map a Unicode code point to UTF-8. utf8string must have at least
* unicode_utf8len(c) bytes available.
*/
static inline unsigned char *
unicode_to_utf8(pg_wchar c, unsigned char *utf8string)
{
if (c <= 0x7F)
{
utf8string[0] = c;
}
else if (c <= 0x7FF)
{
utf8string[0] = 0xC0 | ((c >> 6) & 0x1F);
utf8string[1] = 0x80 | (c & 0x3F);
}
else if (c <= 0xFFFF)
{
utf8string[0] = 0xE0 | ((c >> 12) & 0x0F);
utf8string[1] = 0x80 | ((c >> 6) & 0x3F);
utf8string[2] = 0x80 | (c & 0x3F);
}
else
{
utf8string[0] = 0xF0 | ((c >> 18) & 0x07);
utf8string[1] = 0x80 | ((c >> 12) & 0x3F);
utf8string[2] = 0x80 | ((c >> 6) & 0x3F);
utf8string[3] = 0x80 | (c & 0x3F);
}
return utf8string;
}
/*
* Number of bytes needed to represent the given char in UTF8.
*/