Performance optimization to sqlite3Dequote() and its callers.

FossilOrigin-Name: 9efe2265b1e70172778d333c5b9d9a76095427ab

4 files changed, 14 insertions, 19 deletions

diff --git a/src/expr.c b/src/expr.c
index 0de6378c0..094a454ab 100644
--- a/src/expr.c
+++ b/src/expr.c
@@ -471,15 +471,13 @@ Expr *sqlite3ExprAlloc(
         pNew->flags |= EP_IntValue;
         pNew->u.iValue = iValue;
       }else{
-        int c;
         pNew->u.zToken = (char*)&pNew[1];
         assert( pToken->z!=0 || pToken->n==0 );
         if( pToken->n ) memcpy(pNew->u.zToken, pToken->z, pToken->n);
         pNew->u.zToken[pToken->n] = 0;
-        if( dequote && nExtra>=3 
-             && ((c = pToken->z[0])=='\'' || c=='"' || c=='[' || c=='`') ){
+        if( dequote && sqlite3Isquote(pNew->u.zToken[0]) ){
+          if( pNew->u.zToken[0]=='"' ) pNew->flags |= EP_DblQuoted;
           sqlite3Dequote(pNew->u.zToken);
-          if( c=='"' ) pNew->flags |= EP_DblQuoted;
         }
       }
     }
@@ -1229,7 +1227,7 @@ void sqlite3ExprListSetName(
     pItem = &pList->a[pList->nExpr-1];
     assert( pItem->zName==0 );
     pItem->zName = sqlite3DbStrNDup(pParse->db, pName->z, pName->n);
-    if( dequote && pItem->zName ) sqlite3Dequote(pItem->zName);
+    if( dequote ) sqlite3Dequote(pItem->zName);
   }
 }
 
diff --git a/src/global.c b/src/global.c
index bd70b3827..76901a89b 100644
--- a/src/global.c
+++ b/src/global.c
@@ -70,6 +70,7 @@ const unsigned char sqlite3UpperToLower[] = {
 **   isxdigit()                       0x08
 **   toupper()                        0x20
 **   SQLite identifier character      0x40
+**   Quote character                  0x80
 **
 ** Bit 0x20 is set if the mapped character requires translation to upper
 ** case. i.e. if the character is a lower-case ASCII character.
@@ -95,7 +96,7 @@ const unsigned char sqlite3CtypeMap[256] = {
   0x00, 0x01, 0x01, 0x01, 0x01, 0x01, 0x00, 0x00,  /* 08..0f    ........ */
   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  /* 10..17    ........ */
   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  /* 18..1f    ........ */
-  0x01, 0x00, 0x00, 0x00, 0x40, 0x00, 0x00, 0x00,  /* 20..27     !"#$%&' */
+  0x01, 0x00, 0x80, 0x00, 0x40, 0x00, 0x00, 0x80,  /* 20..27     !"#$%&' */
   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  /* 28..2f    ()*+,-./ */
   0x0c, 0x0c, 0x0c, 0x0c, 0x0c, 0x0c, 0x0c, 0x0c,  /* 30..37    01234567 */
   0x0c, 0x0c, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,  /* 38..3f    89:;<=>? */
@@ -103,8 +104,8 @@ const unsigned char sqlite3CtypeMap[256] = {
   0x00, 0x0a, 0x0a, 0x0a, 0x0a, 0x0a, 0x0a, 0x02,  /* 40..47    @ABCDEFG */
   0x02, 0x02, 0x02, 0x02, 0x02, 0x02, 0x02, 0x02,  /* 48..4f    HIJKLMNO */
   0x02, 0x02, 0x02, 0x02, 0x02, 0x02, 0x02, 0x02,  /* 50..57    PQRSTUVW */
-  0x02, 0x02, 0x02, 0x00, 0x00, 0x00, 0x00, 0x40,  /* 58..5f    XYZ[\]^_ */
-  0x00, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x22,  /* 60..67    `abcdefg */
+  0x02, 0x02, 0x02, 0x80, 0x00, 0x00, 0x00, 0x40,  /* 58..5f    XYZ[\]^_ */
+  0x80, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x2a, 0x22,  /* 60..67    `abcdefg */
   0x22, 0x22, 0x22, 0x22, 0x22, 0x22, 0x22, 0x22,  /* 68..6f    hijklmno */
   0x22, 0x22, 0x22, 0x22, 0x22, 0x22, 0x22, 0x22,  /* 70..77    pqrstuvw */
   0x22, 0x22, 0x22, 0x00, 0x00, 0x00, 0x00, 0x00,  /* 78..7f    xyz{|}~. */
diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index 1b0325254..f9fab8e32 100644
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -3302,6 +3302,7 @@ int sqlite3CantopenError(int);
 # define sqlite3Isdigit(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x04)
 # define sqlite3Isxdigit(x)  (sqlite3CtypeMap[(unsigned char)(x)]&0x08)
 # define sqlite3Tolower(x)   (sqlite3UpperToLower[(unsigned char)(x)])
+# define sqlite3Isquote(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x80)
 #else
 # define sqlite3Toupper(x)   toupper((unsigned char)(x))
 # define sqlite3Isspace(x)   isspace((unsigned char)(x))
@@ -3310,6 +3311,7 @@ int sqlite3CantopenError(int);
 # define sqlite3Isdigit(x)   isdigit((unsigned char)(x))
 # define sqlite3Isxdigit(x)  isxdigit((unsigned char)(x))
 # define sqlite3Tolower(x)   tolower((unsigned char)(x))
+# define sqlite3Isquote(x)   ((x)=='"'||(x)=='\''||(x)=='['||(x)=='`')
 #endif
 #ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
 int sqlite3IsIdChar(u8);
@@ -3433,7 +3435,7 @@ char *sqlite3VMPrintf(sqlite3*,const char*, va_list);
 
 void sqlite3SetString(char **, sqlite3*, const char*);
 void sqlite3ErrorMsg(Parse*, const char*, ...);
-int sqlite3Dequote(char*);
+void sqlite3Dequote(char*);
 void sqlite3TokenInit(Token*,char*);
 int sqlite3KeywordCode(const unsigned char*, int);
 int sqlite3RunParser(Parse*, const char*, char **);
diff --git a/src/util.c b/src/util.c
index d2c6ec8e8..2f77a6033 100644
--- a/src/util.c
+++ b/src/util.c
@@ -242,18 +242,13 @@ void sqlite3ErrorMsg(Parse *pParse, const char *zFormat, ...){
 ** brackets from around identifiers.  For example:  "[a-b-c]" becomes
 ** "a-b-c".
 */
-int sqlite3Dequote(char *z){
+void sqlite3Dequote(char *z){
   char quote;
   int i, j;
-  if( z==0 ) return -1;
+  if( z==0 ) return;
   quote = z[0];
-  switch( quote ){
-    case '\'':  break;
-    case '"':   break;
-    case '`':   break;                /* For MySQL compatibility */
-    case '[':   quote = ']';  break;  /* For MS SqlServer compatibility */
-    default:    return -1;
-  }
+  if( !sqlite3Isquote(quote) ) return;
+  if( quote=='[' ) quote = ']';
   for(i=1, j=0;; i++){
     assert( z[i] );
     if( z[i]==quote ){
@@ -268,7 +263,6 @@ int sqlite3Dequote(char *z){
     }
   }
   z[j] = 0;
-  return j;
 }
 
 /*