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More performance optimization for the LIKE and GLOB operators.

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FossilOrigin-Name: 5ab1023d6cfe31fa8a194804b8216058977ac973
This commit is contained in:
drh
2014-09-25 03:51:37 +00:00
parent 97348b37c2
commit 88b3322f27
3 changed files with 86 additions and 74 deletions
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146
src/func.c
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@@ -567,10 +567,12 @@ struct compareInfo {
** whereas only characters less than 0x80 do in ASCII.
*/
#if defined(SQLITE_EBCDIC)
# define sqlite3Utf8Read(A) (*((*A)++))
# define GlobUpperToLower(A) A = sqlite3UpperToLower[A]
# define sqlite3Utf8Read(A) (*((*A)++))
# define GlobUpperToLower(A) A = sqlite3UpperToLower[A]
# define GlobUpperToLowerAscii(A) A = sqlite3UpperToLower[A]
#else
# define GlobUpperToLower(A) if( !((A)&~0x7f) ){ A = sqlite3UpperToLower[A]; }
# define GlobUpperToLower(A) if( A<=0x7f ){ A = sqlite3UpperToLower[A]; }
# define GlobUpperToLowerAscii(A) A = sqlite3UpperToLower[A]
#endif
static const struct compareInfo globInfo = { '*', '?', '[', 0 };
@@ -618,10 +620,17 @@ static int patternCompare(
u32 c, c2;
int invert;
int seen;
u8 matchOne = pInfo->matchOne;
u8 matchAll = pInfo->matchAll;
u8 matchSet = pInfo->matchSet;
u8 noCase = pInfo->noCase;
u32 matchOne = pInfo->matchOne;
u32 matchAll = pInfo->matchAll;
u32 matchOther;
u8 noCase = pInfo->noCase;
/* The GLOB operator does not have an ESCAPE clause. And LIKE does not
** have the matchSet operator. So we either have to look for one or
** the other, never both. Hence the single variable matchOther is used
** to store the one we have to look for.
*/
matchOther = esc ? esc : pInfo->matchSet;
while( (c = sqlite3Utf8Read(&zPattern))!=0 ){
if( c==matchAll ){
@@ -633,26 +642,26 @@ static int patternCompare(
}
if( c==0 ){
return 1;
}else if( c==esc ){
c = sqlite3Utf8Read(&zPattern);
if( c==0 ){
return 0;
}else if( c==matchOther ){
if( esc ){
c = sqlite3Utf8Read(&zPattern);
if( c==0 ) return 0;
}else{
assert( matchOther<0x80 ); /* '[' is a single-byte character */
while( *zString
&& patternCompare(&zPattern[-1],zString,pInfo,esc)==0 ){
SQLITE_SKIP_UTF8(zString);
}
return *zString!=0;
}
}else if( c==matchSet ){
assert( esc==0 ); /* This is GLOB, not LIKE */
assert( matchSet<0x80 ); /* '[' is a single-byte character */
while( *zString && patternCompare(&zPattern[-1],zString,pInfo,esc)==0 ){
SQLITE_SKIP_UTF8(zString);
}
return *zString!=0;
}
while( (c2 = sqlite3Utf8Read(&zString))!=0 ){
if( noCase ){
if( noCase && c<0x80 ){
GlobUpperToLower(c2);
GlobUpperToLower(c);
GlobUpperToLowerAscii(c);
while( c2 != 0 && c2 != c ){
c2 = sqlite3Utf8Read(&zString);
GlobUpperToLower(c2);
do{ c2 = *(zString++); }while( c2>0x7f );
GlobUpperToLowerAscii(c2);
}
}else{
while( c2 != 0 && c2 != c ){
@@ -663,55 +672,58 @@ static int patternCompare(
if( patternCompare(zPattern,zString,pInfo,esc) ) return 1;
}
return 0;
}else if( c==matchOne ){
}
if( c==matchOne ){
if( sqlite3Utf8Read(&zString)==0 ){
return 0;
}
}else if( c==matchSet ){
u32 prior_c = 0;
assert( esc==0 ); /* This only occurs for GLOB, not LIKE */
seen = 0;
invert = 0;
c = sqlite3Utf8Read(&zString);
if( c==0 ) return 0;
c2 = sqlite3Utf8Read(&zPattern);
if( c2=='^' ){
invert = 1;
c2 = sqlite3Utf8Read(&zPattern);
}
if( c2==']' ){
if( c==']' ) seen = 1;
c2 = sqlite3Utf8Read(&zPattern);
}
while( c2 && c2!=']' ){
if( c2=='-' && zPattern[0]!=']' && zPattern[0]!=0 && prior_c>0 ){
c2 = sqlite3Utf8Read(&zPattern);
if( c>=prior_c && c<=c2 ) seen = 1;
prior_c = 0;
}else{
if( c==c2 ){
seen = 1;
}
prior_c = c2;
}
c2 = sqlite3Utf8Read(&zPattern);
}
if( c2==0 || (seen ^ invert)==0 ){
return 0;
}
}else{
c2 = sqlite3Utf8Read(&zString);
if( c==esc ){
c = sqlite3Utf8Read(&zPattern);
}
if( noCase ){
GlobUpperToLower(c);
GlobUpperToLower(c2);
}
if( c!=c2 ){
return 0;
}else{
continue;
}
}
if( c==matchOther ){
if( esc ){
c = sqlite3Utf8Read(&zPattern);
if( c==0 ) return 0;
}else{
u32 prior_c = 0;
seen = 0;
invert = 0;
c = sqlite3Utf8Read(&zString);
if( c==0 ) return 0;
c2 = sqlite3Utf8Read(&zPattern);
if( c2=='^' ){
invert = 1;
c2 = sqlite3Utf8Read(&zPattern);
}
if( c2==']' ){
if( c==']' ) seen = 1;
c2 = sqlite3Utf8Read(&zPattern);
}
while( c2 && c2!=']' ){
if( c2=='-' && zPattern[0]!=']' && zPattern[0]!=0 && prior_c>0 ){
c2 = sqlite3Utf8Read(&zPattern);
if( c>=prior_c && c<=c2 ) seen = 1;
prior_c = 0;
}else{
if( c==c2 ){
seen = 1;
}
prior_c = c2;
}
c2 = sqlite3Utf8Read(&zPattern);
}
if( c2==0 || (seen ^ invert)==0 ){
return 0;
}
continue;
}
}
c2 = sqlite3Utf8Read(&zString);
if( c==c2 ) continue;
if( !noCase ) return 0;
GlobUpperToLower(c);
GlobUpperToLower(c2);
if( c!=c2 ) return 0;
}
return *zString==0;
}