-C Clean\sup\sthe\sIN\soperator\scode\sgeneration\slogic\sto\smake\sit\seasier\sto\sreason\nabout.\s\sIn\sthe\sprocess,\simprove\scode\sgeneration\sto\somit\ssome\sunused\sOP_Null\noperations.
-D 2014-08-01T15:51:36.528
+C Remove\san\sunnecessary\sOP_Null\sin\sthe\sIN-operator\slogic.\s\sAttempt\sto\sclarify\ncomments\sexplaining\sthe\sIN-operator\scode,\sthough\sit\sis\snot\sclear\sthat\sthe\ncomments\sare\scorrect\seven\syet\s-\smore\swork\sto\sbe\sdone.
+D 2014-08-01T18:00:24.770
F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
F Makefile.in 5eb79e334a5de69c87740edd56af6527dd219308
F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
F src/ctime.c 0231df905e2c4abba4483ee18ffc05adc321df2a
F src/date.c 593c744b2623971e45affd0bde347631bdfa4625
F src/delete.c bcf8f72126cea80fc3d5bc5494cf19b3f8935aaf
-F src/expr.c 1f7fa7ddbdffd89898a3ce5ff1e57d137ec87aa5
+F src/expr.c 45da7f2dd6b5c52b3210387956711d578bdceb37
F src/fault.c 160a0c015b6c2629d3899ed2daf63d75754a32bb
F src/fkey.c 8545f3b36da47473e10800ea4fb0810fd4062514
F src/func.c 3bc223ea36cd29a91c481485343d0ee4257ab8dc
F src/utf.c a0314e637768a030e6e84a957d0c4f6ba910cc05
F src/util.c 3076bdd51cdbf60a6e2e57fada745be37133c73e
F src/vacuum.c 3728d74919d4fb1356f9e9a13e27773db60b7179
-F src/vdbe.c 115e08834b883964d9a480f685d8601826c5792a
+F src/vdbe.c b9e6866e43a61ca4080410f27c4bb52823495186
F src/vdbe.h c63fad052c9e7388d551e556e119c0bcf6bebdf8
F src/vdbeInt.h f5513f2b5ac1e2c5128996c7ea23add256a301df
F src/vdbeapi.c 24e40422382beb774daab11fe9fe9d37e8a04949
F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4
F tool/warnings.sh 0abfd78ceb09b7f7c27c688c8e3fe93268a13b32
F tool/win/sqlite.vsix deb315d026cc8400325c5863eef847784a219a2f
-P 9abcf2698c09f4f6a44a68e74f9f6b538f3253d6 e13175d3579e1045165bab091b3b28951d691704
-R b49330a02feffafe84f051ae1dbb9076
-T +closed e13175d3579e1045165bab091b3b28951d691704
+P 7c6fbcfe6ed5739e8e4639b7b123fbf9828cbfc0
+R 76f22de612006799aae8055deaa164fe
U drh
-Z e21436d3fd2e7daacda65f50d724cf15
+Z ebc1ba4c7f530e221b3bc2fcb7e1119a
**
** When the b-tree is being used for membership tests, the calling function
** might need to know whether or not the RHS side of the IN operator
-** contains a NULL. If prNotFound is not NULL and
+** contains a NULL. If prRhsHasNull is not a NULL pointer and
** if there is any chance that the (...) might contain a NULL value at
** runtime, then a register is allocated and the register number written
-** to *prNotFound. If there is no chance that the (...) contains a
-** NULL value, then *prNotFound is left unchanged.
+** to *prRhsHasNull. If there is no chance that the (...) contains a
+** NULL value, then *prRhsHasNull is left unchanged.
**
-** If a register is allocated and its location stored in *prNotFound, then
-** its initial value is NULL. If the (...) does not remain constant
-** for the duration of the query (i.e. the SELECT within the (...)
-** is a correlated subquery) then the value of the allocated register is
-** reset to NULL each time the subquery is rerun. This allows the
-** caller to use vdbe code equivalent to the following:
+** If a register is allocated and its location stored in *prRhsHasNull, then
+** the value in that register will be:
**
-** if( register==NULL ){
-** has_null = <test if data structure contains null>
-** register = 1
+** 0 if the (...) contains no NULL values
+** 1 if the (...) does not contain NULL values
+** NULL if we do not yet know if (...) contains NULLs
+**
+** If the (...) does not remain constant for the duration of the query
+** (i.e. the SELECT within the (...) is a correlated subquery) then the
+** value of the allocated register is reset to NULL each time the subquery
+** is rerun. This allows the caller to use vdbe code equivalent to the
+** following:
+**
+** if( r[*prRhsHasNull] IS NULL ){
+** r[*prRhsHasNull] = <test if data structure contains null>
** }
**
** in order to avoid running the <test if data structure contains null>
** test more often than is necessary.
*/
#ifndef SQLITE_OMIT_SUBQUERY
-int sqlite3FindInIndex(Parse *pParse, Expr *pX, u32 inFlags, int *prNotFound){
+int sqlite3FindInIndex(Parse *pParse, Expr *pX, u32 inFlags, int *prRhsHasNull){
Select *p; /* SELECT to the right of IN operator */
int eType = 0; /* Type of RHS table. IN_INDEX_* */
int iTab = pParse->nTab++; /* Cursor of the RHS table */
assert( IN_INDEX_INDEX_DESC == IN_INDEX_INDEX_ASC+1 );
eType = IN_INDEX_INDEX_ASC + pIdx->aSortOrder[0];
- if( prNotFound && !pTab->aCol[iCol].notNull ){
- *prNotFound = ++pParse->nMem;
- sqlite3VdbeAddOp2(v, OP_Null, 0, *prNotFound);
+ if( prRhsHasNull && !pTab->aCol[iCol].notNull ){
+ *prRhsHasNull = ++pParse->nMem;
+ sqlite3VdbeAddOp2(v, OP_Null, 0, *prRhsHasNull);
}
sqlite3VdbeJumpHere(v, iAddr);
}
if( pX->pLeft->iColumn<0 && !ExprHasProperty(pX, EP_xIsSelect) ){
eType = IN_INDEX_ROWID;
}
- }else if( prNotFound ){
- *prNotFound = rMayHaveNull = ++pParse->nMem;
- sqlite3VdbeAddOp2(v, OP_Null, 0, rMayHaveNull);
+ }else if( prRhsHasNull ){
+ *prRhsHasNull = rMayHaveNull = ++pParse->nMem;
}
sqlite3CodeSubselect(pParse, pX, rMayHaveNull, eType==IN_INDEX_ROWID);
pParse->nQueryLoop = savedNQueryLoop;
**
** Jump to P2 if the value in register P1 is true. The value
** is considered true if it is numeric and non-zero. If the value
-** in P1 is NULL then take the jump if P3 is non-zero.
+** in P1 is NULL then take the jump if and only if P3 is non-zero.
*/
/* Opcode: IfNot P1 P2 P3 * *
**
** Jump to P2 if the value in register P1 is False. The value
** is considered false if it has a numeric value of zero. If the value
-** in P1 is NULL then take the jump if P3 is zero.
+** in P1 is NULL then take the jump if and only if P3 is non-zero.
*/
case OP_If: /* jump, in1 */
case OP_IfNot: { /* jump, in1 */
projects / thirdparty / sqlite.git / commitdiff
