diff options
Diffstat (limited to 'chromium/third_party/sqlite/sqlite-src-3240000/src/expr.c')
| -rw-r--r-- | chromium/third_party/sqlite/sqlite-src-3240000/src/expr.c | 5519 |
1 files changed, 0 insertions, 5519 deletions
diff --git a/chromium/third_party/sqlite/sqlite-src-3240000/src/expr.c b/chromium/third_party/sqlite/sqlite-src-3240000/src/expr.c deleted file mode 100644 index 91eb44b8eba..00000000000 --- a/chromium/third_party/sqlite/sqlite-src-3240000/src/expr.c +++ /dev/null @@ -1,5519 +0,0 @@ -/* -** 2001 September 15 -** -** The author disclaims copyright to this source code. In place of -** a legal notice, here is a blessing: -** -** May you do good and not evil. -** May you find forgiveness for yourself and forgive others. -** May you share freely, never taking more than you give. -** -************************************************************************* -** This file contains routines used for analyzing expressions and -** for generating VDBE code that evaluates expressions in SQLite. -*/ -#include "sqliteInt.h" - -/* Forward declarations */ -static void exprCodeBetween(Parse*,Expr*,int,void(*)(Parse*,Expr*,int,int),int); -static int exprCodeVector(Parse *pParse, Expr *p, int *piToFree); - -/* -** Return the affinity character for a single column of a table. -*/ -char sqlite3TableColumnAffinity(Table *pTab, int iCol){ - assert( iCol<pTab->nCol ); - return iCol>=0 ? pTab->aCol[iCol].affinity : SQLITE_AFF_INTEGER; -} - -/* -** Return the 'affinity' of the expression pExpr if any. -** -** If pExpr is a column, a reference to a column via an 'AS' alias, -** or a sub-select with a column as the return value, then the -** affinity of that column is returned. Otherwise, 0x00 is returned, -** indicating no affinity for the expression. -** -** i.e. the WHERE clause expressions in the following statements all -** have an affinity: -** -** CREATE TABLE t1(a); -** SELECT * FROM t1 WHERE a; -** SELECT a AS b FROM t1 WHERE b; -** SELECT * FROM t1 WHERE (select a from t1); -*/ -char sqlite3ExprAffinity(Expr *pExpr){ - int op; - pExpr = sqlite3ExprSkipCollate(pExpr); - if( pExpr->flags & EP_Generic ) return 0; - op = pExpr->op; - if( op==TK_SELECT ){ - assert( pExpr->flags&EP_xIsSelect ); - return sqlite3ExprAffinity(pExpr->x.pSelect->pEList->a[0].pExpr); - } - if( op==TK_REGISTER ) op = pExpr->op2; -#ifndef SQLITE_OMIT_CAST - if( op==TK_CAST ){ - assert( !ExprHasProperty(pExpr, EP_IntValue) ); - return sqlite3AffinityType(pExpr->u.zToken, 0); - } -#endif - if( (op==TK_AGG_COLUMN || op==TK_COLUMN) && pExpr->pTab ){ - return sqlite3TableColumnAffinity(pExpr->pTab, pExpr->iColumn); - } - if( op==TK_SELECT_COLUMN ){ - assert( pExpr->pLeft->flags&EP_xIsSelect ); - return sqlite3ExprAffinity( - pExpr->pLeft->x.pSelect->pEList->a[pExpr->iColumn].pExpr - ); - } - return pExpr->affinity; -} - -/* -** Set the collating sequence for expression pExpr to be the collating -** sequence named by pToken. Return a pointer to a new Expr node that -** implements the COLLATE operator. -** -** If a memory allocation error occurs, that fact is recorded in pParse->db -** and the pExpr parameter is returned unchanged. -*/ -Expr *sqlite3ExprAddCollateToken( - Parse *pParse, /* Parsing context */ - Expr *pExpr, /* Add the "COLLATE" clause to this expression */ - const Token *pCollName, /* Name of collating sequence */ - int dequote /* True to dequote pCollName */ -){ - if( pCollName->n>0 ){ - Expr *pNew = sqlite3ExprAlloc(pParse->db, TK_COLLATE, pCollName, dequote); - if( pNew ){ - pNew->pLeft = pExpr; - pNew->flags |= EP_Collate|EP_Skip; - pExpr = pNew; - } - } - return pExpr; -} -Expr *sqlite3ExprAddCollateString(Parse *pParse, Expr *pExpr, const char *zC){ - Token s; - assert( zC!=0 ); - sqlite3TokenInit(&s, (char*)zC); - return sqlite3ExprAddCollateToken(pParse, pExpr, &s, 0); -} - -/* -** Skip over any TK_COLLATE operators and any unlikely() -** or likelihood() function at the root of an expression. -*/ -Expr *sqlite3ExprSkipCollate(Expr *pExpr){ - while( pExpr && ExprHasProperty(pExpr, EP_Skip) ){ - if( ExprHasProperty(pExpr, EP_Unlikely) ){ - assert( !ExprHasProperty(pExpr, EP_xIsSelect) ); - assert( pExpr->x.pList->nExpr>0 ); - assert( pExpr->op==TK_FUNCTION ); - pExpr = pExpr->x.pList->a[0].pExpr; - }else{ - assert( pExpr->op==TK_COLLATE ); - pExpr = pExpr->pLeft; - } - } - return pExpr; -} - -/* -** Return the collation sequence for the expression pExpr. If -** there is no defined collating sequence, return NULL. -** -** See also: sqlite3ExprNNCollSeq() -** -** The sqlite3ExprNNCollSeq() works the same exact that it returns the -** default collation if pExpr has no defined collation. -** -** The collating sequence might be determined by a COLLATE operator -** or by the presence of a column with a defined collating sequence. -** COLLATE operators take first precedence. Left operands take -** precedence over right operands. -*/ -CollSeq *sqlite3ExprCollSeq(Parse *pParse, Expr *pExpr){ - sqlite3 *db = pParse->db; - CollSeq *pColl = 0; - Expr *p = pExpr; - while( p ){ - int op = p->op; - if( p->flags & EP_Generic ) break; - if( op==TK_CAST || op==TK_UPLUS ){ - p = p->pLeft; - continue; - } - if( op==TK_COLLATE || (op==TK_REGISTER && p->op2==TK_COLLATE) ){ - pColl = sqlite3GetCollSeq(pParse, ENC(db), 0, p->u.zToken); - break; - } - if( (op==TK_AGG_COLUMN || op==TK_COLUMN - || op==TK_REGISTER || op==TK_TRIGGER) - && p->pTab!=0 - ){ - /* op==TK_REGISTER && p->pTab!=0 happens when pExpr was originally - ** a TK_COLUMN but was previously evaluated and cached in a register */ - int j = p->iColumn; - if( j>=0 ){ - const char *zColl = p->pTab->aCol[j].zColl; - pColl = sqlite3FindCollSeq(db, ENC(db), zColl, 0); - } - break; - } - if( p->flags & EP_Collate ){ - if( p->pLeft && (p->pLeft->flags & EP_Collate)!=0 ){ - p = p->pLeft; - }else{ - Expr *pNext = p->pRight; - /* The Expr.x union is never used at the same time as Expr.pRight */ - assert( p->x.pList==0 || p->pRight==0 ); - /* p->flags holds EP_Collate and p->pLeft->flags does not. And - ** p->x.pSelect cannot. So if p->x.pLeft exists, it must hold at - ** least one EP_Collate. Thus the following two ALWAYS. */ - if( p->x.pList!=0 && ALWAYS(!ExprHasProperty(p, EP_xIsSelect)) ){ - int i; - for(i=0; ALWAYS(i<p->x.pList->nExpr); i++){ - if( ExprHasProperty(p->x.pList->a[i].pExpr, EP_Collate) ){ - pNext = p->x.pList->a[i].pExpr; - break; - } - } - } - p = pNext; - } - }else{ - break; - } - } - if( sqlite3CheckCollSeq(pParse, pColl) ){ - pColl = 0; - } - return pColl; -} - -/* -** Return the collation sequence for the expression pExpr. If -** there is no defined collating sequence, return a pointer to the -** defautl collation sequence. -** -** See also: sqlite3ExprCollSeq() -** -** The sqlite3ExprCollSeq() routine works the same except that it -** returns NULL if there is no defined collation. -*/ -CollSeq *sqlite3ExprNNCollSeq(Parse *pParse, Expr *pExpr){ - CollSeq *p = sqlite3ExprCollSeq(pParse, pExpr); - if( p==0 ) p = pParse->db->pDfltColl; - assert( p!=0 ); - return p; -} - -/* -** Return TRUE if the two expressions have equivalent collating sequences. -*/ -int sqlite3ExprCollSeqMatch(Parse *pParse, Expr *pE1, Expr *pE2){ - CollSeq *pColl1 = sqlite3ExprNNCollSeq(pParse, pE1); - CollSeq *pColl2 = sqlite3ExprNNCollSeq(pParse, pE2); - return sqlite3StrICmp(pColl1->zName, pColl2->zName)==0; -} - -/* -** pExpr is an operand of a comparison operator. aff2 is the -** type affinity of the other operand. This routine returns the -** type affinity that should be used for the comparison operator. -*/ -char sqlite3CompareAffinity(Expr *pExpr, char aff2){ - char aff1 = sqlite3ExprAffinity(pExpr); - if( aff1 && aff2 ){ - /* Both sides of the comparison are columns. If one has numeric - ** affinity, use that. Otherwise use no affinity. - */ - if( sqlite3IsNumericAffinity(aff1) || sqlite3IsNumericAffinity(aff2) ){ - return SQLITE_AFF_NUMERIC; - }else{ - return SQLITE_AFF_BLOB; - } - }else if( !aff1 && !aff2 ){ - /* Neither side of the comparison is a column. Compare the - ** results directly. - */ - return SQLITE_AFF_BLOB; - }else{ - /* One side is a column, the other is not. Use the columns affinity. */ - assert( aff1==0 || aff2==0 ); - return (aff1 + aff2); - } -} - -/* -** pExpr is a comparison operator. Return the type affinity that should -** be applied to both operands prior to doing the comparison. -*/ -static char comparisonAffinity(Expr *pExpr){ - char aff; - assert( pExpr->op==TK_EQ || pExpr->op==TK_IN || pExpr->op==TK_LT || - pExpr->op==TK_GT || pExpr->op==TK_GE || pExpr->op==TK_LE || - pExpr->op==TK_NE || pExpr->op==TK_IS || pExpr->op==TK_ISNOT ); - assert( pExpr->pLeft ); - aff = sqlite3ExprAffinity(pExpr->pLeft); - if( pExpr->pRight ){ - aff = sqlite3CompareAffinity(pExpr->pRight, aff); - }else if( ExprHasProperty(pExpr, EP_xIsSelect) ){ - aff = sqlite3CompareAffinity(pExpr->x.pSelect->pEList->a[0].pExpr, aff); - }else if( aff==0 ){ - aff = SQLITE_AFF_BLOB; - } - return aff; -} - -/* -** pExpr is a comparison expression, eg. '=', '<', IN(...) etc. -** idx_affinity is the affinity of an indexed column. Return true -** if the index with affinity idx_affinity may be used to implement -** the comparison in pExpr. -*/ -int sqlite3IndexAffinityOk(Expr *pExpr, char idx_affinity){ - char aff = comparisonAffinity(pExpr); - switch( aff ){ - case SQLITE_AFF_BLOB: - return 1; - case SQLITE_AFF_TEXT: - return idx_affinity==SQLITE_AFF_TEXT; - default: - return sqlite3IsNumericAffinity(idx_affinity); - } -} - -/* -** Return the P5 value that should be used for a binary comparison -** opcode (OP_Eq, OP_Ge etc.) used to compare pExpr1 and pExpr2. -*/ -static u8 binaryCompareP5(Expr *pExpr1, Expr *pExpr2, int jumpIfNull){ - u8 aff = (char)sqlite3ExprAffinity(pExpr2); - aff = (u8)sqlite3CompareAffinity(pExpr1, aff) | (u8)jumpIfNull; - return aff; -} - -/* -** Return a pointer to the collation sequence that should be used by -** a binary comparison operator comparing pLeft and pRight. -** -** If the left hand expression has a collating sequence type, then it is -** used. Otherwise the collation sequence for the right hand expression -** is used, or the default (BINARY) if neither expression has a collating -** type. -** -** Argument pRight (but not pLeft) may be a null pointer. In this case, -** it is not considered. -*/ -CollSeq *sqlite3BinaryCompareCollSeq( - Parse *pParse, - Expr *pLeft, - Expr *pRight -){ - CollSeq *pColl; - assert( pLeft ); - if( pLeft->flags & EP_Collate ){ - pColl = sqlite3ExprCollSeq(pParse, pLeft); - }else if( pRight && (pRight->flags & EP_Collate)!=0 ){ - pColl = sqlite3ExprCollSeq(pParse, pRight); - }else{ - pColl = sqlite3ExprCollSeq(pParse, pLeft); - if( !pColl ){ - pColl = sqlite3ExprCollSeq(pParse, pRight); - } - } - return pColl; -} - -/* -** Generate code for a comparison operator. -*/ -static int codeCompare( - Parse *pParse, /* The parsing (and code generating) context */ - Expr *pLeft, /* The left operand */ - Expr *pRight, /* The right operand */ - int opcode, /* The comparison opcode */ - int in1, int in2, /* Register holding operands */ - int dest, /* Jump here if true. */ - int jumpIfNull /* If true, jump if either operand is NULL */ -){ - int p5; - int addr; - CollSeq *p4; - - p4 = sqlite3BinaryCompareCollSeq(pParse, pLeft, pRight); - p5 = binaryCompareP5(pLeft, pRight, jumpIfNull); - addr = sqlite3VdbeAddOp4(pParse->pVdbe, opcode, in2, dest, in1, - (void*)p4, P4_COLLSEQ); - sqlite3VdbeChangeP5(pParse->pVdbe, (u8)p5); - return addr; -} - -/* -** Return true if expression pExpr is a vector, or false otherwise. -** -** A vector is defined as any expression that results in two or more -** columns of result. Every TK_VECTOR node is an vector because the -** parser will not generate a TK_VECTOR with fewer than two entries. -** But a TK_SELECT might be either a vector or a scalar. It is only -** considered a vector if it has two or more result columns. -*/ -int sqlite3ExprIsVector(Expr *pExpr){ - return sqlite3ExprVectorSize(pExpr)>1; -} - -/* -** If the expression passed as the only argument is of type TK_VECTOR -** return the number of expressions in the vector. Or, if the expression -** is a sub-select, return the number of columns in the sub-select. For -** any other type of expression, return 1. -*/ -int sqlite3ExprVectorSize(Expr *pExpr){ - u8 op = pExpr->op; - if( op==TK_REGISTER ) op = pExpr->op2; - if( op==TK_VECTOR ){ - return pExpr->x.pList->nExpr; - }else if( op==TK_SELECT ){ - return pExpr->x.pSelect->pEList->nExpr; - }else{ - return 1; - } -} - -/* -** Return a pointer to a subexpression of pVector that is the i-th -** column of the vector (numbered starting with 0). The caller must -** ensure that i is within range. -** -** If pVector is really a scalar (and "scalar" here includes subqueries -** that return a single column!) then return pVector unmodified. -** -** pVector retains ownership of the returned subexpression. -** -** If the vector is a (SELECT ...) then the expression returned is -** just the expression for the i-th term of the result set, and may -** not be ready for evaluation because the table cursor has not yet -** been positioned. -*/ -Expr *sqlite3VectorFieldSubexpr(Expr *pVector, int i){ - assert( i<sqlite3ExprVectorSize(pVector) ); - if( sqlite3ExprIsVector(pVector) ){ - assert( pVector->op2==0 || pVector->op==TK_REGISTER ); - if( pVector->op==TK_SELECT || pVector->op2==TK_SELECT ){ - return pVector->x.pSelect->pEList->a[i].pExpr; - }else{ - return pVector->x.pList->a[i].pExpr; - } - } - return pVector; -} - -/* -** Compute and return a new Expr object which when passed to -** sqlite3ExprCode() will generate all necessary code to compute -** the iField-th column of the vector expression pVector. -** -** It is ok for pVector to be a scalar (as long as iField==0). -** In that case, this routine works like sqlite3ExprDup(). -** -** The caller owns the returned Expr object and is responsible for -** ensuring that the returned value eventually gets freed. -** -** The caller retains ownership of pVector. If pVector is a TK_SELECT, -** then the returned object will reference pVector and so pVector must remain -** valid for the life of the returned object. If pVector is a TK_VECTOR -** or a scalar expression, then it can be deleted as soon as this routine -** returns. -** -** A trick to cause a TK_SELECT pVector to be deleted together with -** the returned Expr object is to attach the pVector to the pRight field -** of the returned TK_SELECT_COLUMN Expr object. -*/ -Expr *sqlite3ExprForVectorField( - Parse *pParse, /* Parsing context */ - Expr *pVector, /* The vector. List of expressions or a sub-SELECT */ - int iField /* Which column of the vector to return */ -){ - Expr *pRet; - if( pVector->op==TK_SELECT ){ - assert( pVector->flags & EP_xIsSelect ); - /* The TK_SELECT_COLUMN Expr node: - ** - ** pLeft: pVector containing TK_SELECT. Not deleted. - ** pRight: not used. But recursively deleted. - ** iColumn: Index of a column in pVector - ** iTable: 0 or the number of columns on the LHS of an assignment - ** pLeft->iTable: First in an array of register holding result, or 0 - ** if the result is not yet computed. - ** - ** sqlite3ExprDelete() specifically skips the recursive delete of - ** pLeft on TK_SELECT_COLUMN nodes. But pRight is followed, so pVector - ** can be attached to pRight to cause this node to take ownership of - ** pVector. Typically there will be multiple TK_SELECT_COLUMN nodes - ** with the same pLeft pointer to the pVector, but only one of them - ** will own the pVector. - */ - pRet = sqlite3PExpr(pParse, TK_SELECT_COLUMN, 0, 0); - if( pRet ){ - pRet->iColumn = iField; - pRet->pLeft = pVector; - } - assert( pRet==0 || pRet->iTable==0 ); - }else{ - if( pVector->op==TK_VECTOR ) pVector = pVector->x.pList->a[iField].pExpr; - pRet = sqlite3ExprDup(pParse->db, pVector, 0); - } - return pRet; -} - -/* -** If expression pExpr is of type TK_SELECT, generate code to evaluate -** it. Return the register in which the result is stored (or, if the -** sub-select returns more than one column, the first in an array -** of registers in which the result is stored). -** -** If pExpr is not a TK_SELECT expression, return 0. -*/ -static int exprCodeSubselect(Parse *pParse, Expr *pExpr){ - int reg = 0; -#ifndef SQLITE_OMIT_SUBQUERY - if( pExpr->op==TK_SELECT ){ - reg = sqlite3CodeSubselect(pParse, pExpr, 0, 0); - } -#endif - return reg; -} - -/* -** Argument pVector points to a vector expression - either a TK_VECTOR -** or TK_SELECT that returns more than one column. This function returns -** the register number of a register that contains the value of -** element iField of the vector. -** -** If pVector is a TK_SELECT expression, then code for it must have -** already been generated using the exprCodeSubselect() routine. In this -** case parameter regSelect should be the first in an array of registers -** containing the results of the sub-select. -** -** If pVector is of type TK_VECTOR, then code for the requested field -** is generated. In this case (*pRegFree) may be set to the number of -** a temporary register to be freed by the caller before returning. -** -** Before returning, output parameter (*ppExpr) is set to point to the -** Expr object corresponding to element iElem of the vector. -*/ -static int exprVectorRegister( - Parse *pParse, /* Parse context */ - Expr *pVector, /* Vector to extract element from */ - int iField, /* Field to extract from pVector */ - int regSelect, /* First in array of registers */ - Expr **ppExpr, /* OUT: Expression element */ - int *pRegFree /* OUT: Temp register to free */ -){ - u8 op = pVector->op; - assert( op==TK_VECTOR || op==TK_REGISTER || op==TK_SELECT ); - if( op==TK_REGISTER ){ - *ppExpr = sqlite3VectorFieldSubexpr(pVector, iField); - return pVector->iTable+iField; - } - if( op==TK_SELECT ){ - *ppExpr = pVector->x.pSelect->pEList->a[iField].pExpr; - return regSelect+iField; - } - *ppExpr = pVector->x.pList->a[iField].pExpr; - return sqlite3ExprCodeTemp(pParse, *ppExpr, pRegFree); -} - -/* -** Expression pExpr is a comparison between two vector values. Compute -** the result of the comparison (1, 0, or NULL) and write that -** result into register dest. -** -** The caller must satisfy the following preconditions: -** -** if pExpr->op==TK_IS: op==TK_EQ and p5==SQLITE_NULLEQ -** if pExpr->op==TK_ISNOT: op==TK_NE and p5==SQLITE_NULLEQ -** otherwise: op==pExpr->op and p5==0 -*/ -static void codeVectorCompare( - Parse *pParse, /* Code generator context */ - Expr *pExpr, /* The comparison operation */ - int dest, /* Write results into this register */ - u8 op, /* Comparison operator */ - u8 p5 /* SQLITE_NULLEQ or zero */ -){ - Vdbe *v = pParse->pVdbe; - Expr *pLeft = pExpr->pLeft; - Expr *pRight = pExpr->pRight; - int nLeft = sqlite3ExprVectorSize(pLeft); - int i; - int regLeft = 0; - int regRight = 0; - u8 opx = op; - int addrDone = sqlite3VdbeMakeLabel(v); - - if( nLeft!=sqlite3ExprVectorSize(pRight) ){ - sqlite3ErrorMsg(pParse, "row value misused"); - return; - } - assert( pExpr->op==TK_EQ || pExpr->op==TK_NE - || pExpr->op==TK_IS || pExpr->op==TK_ISNOT - || pExpr->op==TK_LT || pExpr->op==TK_GT - || pExpr->op==TK_LE || pExpr->op==TK_GE - ); - assert( pExpr->op==op || (pExpr->op==TK_IS && op==TK_EQ) - || (pExpr->op==TK_ISNOT && op==TK_NE) ); - assert( p5==0 || pExpr->op!=op ); - assert( p5==SQLITE_NULLEQ || pExpr->op==op ); - - p5 |= SQLITE_STOREP2; - if( opx==TK_LE ) opx = TK_LT; - if( opx==TK_GE ) opx = TK_GT; - - regLeft = exprCodeSubselect(pParse, pLeft); - regRight = exprCodeSubselect(pParse, pRight); - - for(i=0; 1 /*Loop exits by "break"*/; i++){ - int regFree1 = 0, regFree2 = 0; - Expr *pL, *pR; - int r1, r2; - assert( i>=0 && i<nLeft ); - if( i>0 ) sqlite3ExprCachePush(pParse); - r1 = exprVectorRegister(pParse, pLeft, i, regLeft, &pL, ®Free1); - r2 = exprVectorRegister(pParse, pRight, i, regRight, &pR, ®Free2); - codeCompare(pParse, pL, pR, opx, r1, r2, dest, p5); - testcase(op==OP_Lt); VdbeCoverageIf(v,op==OP_Lt); - testcase(op==OP_Le); VdbeCoverageIf(v,op==OP_Le); - testcase(op==OP_Gt); VdbeCoverageIf(v,op==OP_Gt); - testcase(op==OP_Ge); VdbeCoverageIf(v,op==OP_Ge); - testcase(op==OP_Eq); VdbeCoverageIf(v,op==OP_Eq); - testcase(op==OP_Ne); VdbeCoverageIf(v,op==OP_Ne); - sqlite3ReleaseTempReg(pParse, regFree1); - sqlite3ReleaseTempReg(pParse, regFree2); - if( i>0 ) sqlite3ExprCachePop(pParse); - if( i==nLeft-1 ){ - break; - } - if( opx==TK_EQ ){ - sqlite3VdbeAddOp2(v, OP_IfNot, dest, addrDone); VdbeCoverage(v); - p5 |= SQLITE_KEEPNULL; - }else if( opx==TK_NE ){ - sqlite3VdbeAddOp2(v, OP_If, dest, addrDone); VdbeCoverage(v); - p5 |= SQLITE_KEEPNULL; - }else{ - assert( op==TK_LT || op==TK_GT || op==TK_LE || op==TK_GE ); - sqlite3VdbeAddOp2(v, OP_ElseNotEq, 0, addrDone); - VdbeCoverageIf(v, op==TK_LT); - VdbeCoverageIf(v, op==TK_GT); - VdbeCoverageIf(v, op==TK_LE); - VdbeCoverageIf(v, op==TK_GE); - if( i==nLeft-2 ) opx = op; - } - } - sqlite3VdbeResolveLabel(v, addrDone); -} - -#if SQLITE_MAX_EXPR_DEPTH>0 -/* -** Check that argument nHeight is less than or equal to the maximum -** expression depth allowed. If it is not, leave an error message in -** pParse. -*/ -int sqlite3ExprCheckHeight(Parse *pParse, int nHeight){ - int rc = SQLITE_OK; - int mxHeight = pParse->db->aLimit[SQLITE_LIMIT_EXPR_DEPTH]; - if( nHeight>mxHeight ){ - sqlite3ErrorMsg(pParse, - "Expression tree is too large (maximum depth %d)", mxHeight - ); - rc = SQLITE_ERROR; - } - return rc; -} - -/* The following three functions, heightOfExpr(), heightOfExprList() -** and heightOfSelect(), are used to determine the maximum height -** of any expression tree referenced by the structure passed as the -** first argument. -** -** If this maximum height is greater than the current value pointed -** to by pnHeight, the second parameter, then set *pnHeight to that -** value. -*/ -static void heightOfExpr(Expr *p, int *pnHeight){ - if( p ){ - if( p->nHeight>*pnHeight ){ - *pnHeight = p->nHeight; - } - } -} -static void heightOfExprList(ExprList *p, int *pnHeight){ - if( p ){ - int i; - for(i=0; i<p->nExpr; i++){ - heightOfExpr(p->a[i].pExpr, pnHeight); - } - } -} -static void heightOfSelect(Select *pSelect, int *pnHeight){ - Select *p; - for(p=pSelect; p; p=p->pPrior){ - heightOfExpr(p->pWhere, pnHeight); - heightOfExpr(p->pHaving, pnHeight); - heightOfExpr(p->pLimit, pnHeight); - heightOfExprList(p->pEList, pnHeight); - heightOfExprList(p->pGroupBy, pnHeight); - heightOfExprList(p->pOrderBy, pnHeight); - } -} - -/* -** Set the Expr.nHeight variable in the structure passed as an -** argument. An expression with no children, Expr.pList or -** Expr.pSelect member has a height of 1. Any other expression -** has a height equal to the maximum height of any other -** referenced Expr plus one. -** -** Also propagate EP_Propagate flags up from Expr.x.pList to Expr.flags, -** if appropriate. -*/ -static void exprSetHeight(Expr *p){ - int nHeight = 0; - heightOfExpr(p->pLeft, &nHeight); - heightOfExpr(p->pRight, &nHeight); - if( ExprHasProperty(p, EP_xIsSelect) ){ - heightOfSelect(p->x.pSelect, &nHeight); - }else if( p->x.pList ){ - heightOfExprList(p->x.pList, &nHeight); - p->flags |= EP_Propagate & sqlite3ExprListFlags(p->x.pList); - } - p->nHeight = nHeight + 1; -} - -/* -** Set the Expr.nHeight variable using the exprSetHeight() function. If -** the height is greater than the maximum allowed expression depth, -** leave an error in pParse. -** -** Also propagate all EP_Propagate flags from the Expr.x.pList into -** Expr.flags. -*/ -void sqlite3ExprSetHeightAndFlags(Parse *pParse, Expr *p){ - if( pParse->nErr ) return; - exprSetHeight(p); - sqlite3ExprCheckHeight(pParse, p->nHeight); -} - -/* -** Return the maximum height of any expression tree referenced -** by the select statement passed as an argument. -*/ -int sqlite3SelectExprHeight(Select *p){ - int nHeight = 0; - heightOfSelect(p, &nHeight); - return nHeight; -} -#else /* ABOVE: Height enforcement enabled. BELOW: Height enforcement off */ -/* -** Propagate all EP_Propagate flags from the Expr.x.pList into -** Expr.flags. -*/ -void sqlite3ExprSetHeightAndFlags(Parse *pParse, Expr *p){ - if( p && p->x.pList && !ExprHasProperty(p, EP_xIsSelect) ){ - p->flags |= EP_Propagate & sqlite3ExprListFlags(p->x.pList); - } -} -#define exprSetHeight(y) -#endif /* SQLITE_MAX_EXPR_DEPTH>0 */ - -/* -** This routine is the core allocator for Expr nodes. -** -** Construct a new expression node and return a pointer to it. Memory -** for this node and for the pToken argument is a single allocation -** obtained from sqlite3DbMalloc(). The calling function -** is responsible for making sure the node eventually gets freed. -** -** If dequote is true, then the token (if it exists) is dequoted. -** If dequote is false, no dequoting is performed. The deQuote -** parameter is ignored if pToken is NULL or if the token does not -** appear to be quoted. If the quotes were of the form "..." (double-quotes) -** then the EP_DblQuoted flag is set on the expression node. -** -** Special case: If op==TK_INTEGER and pToken points to a string that -** can be translated into a 32-bit integer, then the token is not -** stored in u.zToken. Instead, the integer values is written -** into u.iValue and the EP_IntValue flag is set. No extra storage -** is allocated to hold the integer text and the dequote flag is ignored. -*/ -Expr *sqlite3ExprAlloc( - sqlite3 *db, /* Handle for sqlite3DbMallocRawNN() */ - int op, /* Expression opcode */ - const Token *pToken, /* Token argument. Might be NULL */ - int dequote /* True to dequote */ -){ - Expr *pNew; - int nExtra = 0; - int iValue = 0; - - assert( db!=0 ); - if( pToken ){ - if( op!=TK_INTEGER || pToken->z==0 - || sqlite3GetInt32(pToken->z, &iValue)==0 ){ - nExtra = pToken->n+1; - assert( iValue>=0 ); - } - } - pNew = sqlite3DbMallocRawNN(db, sizeof(Expr)+nExtra); - if( pNew ){ - memset(pNew, 0, sizeof(Expr)); - pNew->op = (u8)op; - pNew->iAgg = -1; - if( pToken ){ - if( nExtra==0 ){ - pNew->flags |= EP_IntValue|EP_Leaf; - pNew->u.iValue = iValue; - }else{ - 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 && sqlite3Isquote(pNew->u.zToken[0]) ){ - if( pNew->u.zToken[0]=='"' ) pNew->flags |= EP_DblQuoted; - sqlite3Dequote(pNew->u.zToken); - } - } - } -#if SQLITE_MAX_EXPR_DEPTH>0 - pNew->nHeight = 1; -#endif - } - return pNew; -} - -/* -** Allocate a new expression node from a zero-terminated token that has -** already been dequoted. -*/ -Expr *sqlite3Expr( - sqlite3 *db, /* Handle for sqlite3DbMallocZero() (may be null) */ - int op, /* Expression opcode */ - const char *zToken /* Token argument. Might be NULL */ -){ - Token x; - x.z = zToken; - x.n = sqlite3Strlen30(zToken); - return sqlite3ExprAlloc(db, op, &x, 0); -} - -/* -** Attach subtrees pLeft and pRight to the Expr node pRoot. -** -** If pRoot==NULL that means that a memory allocation error has occurred. -** In that case, delete the subtrees pLeft and pRight. -*/ -void sqlite3ExprAttachSubtrees( - sqlite3 *db, - Expr *pRoot, - Expr *pLeft, - Expr *pRight -){ - if( pRoot==0 ){ - assert( db->mallocFailed ); - sqlite3ExprDelete(db, pLeft); - sqlite3ExprDelete(db, pRight); - }else{ - if( pRight ){ - pRoot->pRight = pRight; - pRoot->flags |= EP_Propagate & pRight->flags; - } - if( pLeft ){ - pRoot->pLeft = pLeft; - pRoot->flags |= EP_Propagate & pLeft->flags; - } - exprSetHeight(pRoot); - } -} - -/* -** Allocate an Expr node which joins as many as two subtrees. -** -** One or both of the subtrees can be NULL. Return a pointer to the new -** Expr node. Or, if an OOM error occurs, set pParse->db->mallocFailed, -** free the subtrees and return NULL. -*/ -Expr *sqlite3PExpr( - Parse *pParse, /* Parsing context */ - int op, /* Expression opcode */ - Expr *pLeft, /* Left operand */ - Expr *pRight /* Right operand */ -){ - Expr *p; - if( op==TK_AND && pParse->nErr==0 ){ - /* Take advantage of short-circuit false optimization for AND */ - p = sqlite3ExprAnd(pParse->db, pLeft, pRight); - }else{ - p = sqlite3DbMallocRawNN(pParse->db, sizeof(Expr)); - if( p ){ - memset(p, 0, sizeof(Expr)); - p->op = op & TKFLG_MASK; - p->iAgg = -1; - } - sqlite3ExprAttachSubtrees(pParse->db, p, pLeft, pRight); - } - if( p ) { - sqlite3ExprCheckHeight(pParse, p->nHeight); - } - return p; -} - -/* -** Add pSelect to the Expr.x.pSelect field. Or, if pExpr is NULL (due -** do a memory allocation failure) then delete the pSelect object. -*/ -void sqlite3PExprAddSelect(Parse *pParse, Expr *pExpr, Select *pSelect){ - if( pExpr ){ - pExpr->x.pSelect = pSelect; - ExprSetProperty(pExpr, EP_xIsSelect|EP_Subquery); - sqlite3ExprSetHeightAndFlags(pParse, pExpr); - }else{ - assert( pParse->db->mallocFailed ); - sqlite3SelectDelete(pParse->db, pSelect); - } -} - - -/* -** If the expression is always either TRUE or FALSE (respectively), -** then return 1. If one cannot determine the truth value of the -** expression at compile-time return 0. -** -** This is an optimization. If is OK to return 0 here even if -** the expression really is always false or false (a false negative). -** But it is a bug to return 1 if the expression might have different -** boolean values in different circumstances (a false positive.) -** -** Note that if the expression is part of conditional for a -** LEFT JOIN, then we cannot determine at compile-time whether or not -** is it true or false, so always return 0. -*/ -static int exprAlwaysTrue(Expr *p){ - int v = 0; - if( ExprHasProperty(p, EP_FromJoin) ) return 0; - if( !sqlite3ExprIsInteger(p, &v) ) return 0; - return v!=0; -} -static int exprAlwaysFalse(Expr *p){ - int v = 0; - if( ExprHasProperty(p, EP_FromJoin) ) return 0; - if( !sqlite3ExprIsInteger(p, &v) ) return 0; - return v==0; -} - -/* -** Join two expressions using an AND operator. If either expression is -** NULL, then just return the other expression. -** -** If one side or the other of the AND is known to be false, then instead -** of returning an AND expression, just return a constant expression with -** a value of false. -*/ -Expr *sqlite3ExprAnd(sqlite3 *db, Expr *pLeft, Expr *pRight){ - if( pLeft==0 ){ - return pRight; - }else if( pRight==0 ){ - return pLeft; - }else if( exprAlwaysFalse(pLeft) || exprAlwaysFalse(pRight) ){ - sqlite3ExprDelete(db, pLeft); - sqlite3ExprDelete(db, pRight); - return sqlite3ExprAlloc(db, TK_INTEGER, &sqlite3IntTokens[0], 0); - }else{ - Expr *pNew = sqlite3ExprAlloc(db, TK_AND, 0, 0); - sqlite3ExprAttachSubtrees(db, pNew, pLeft, pRight); - return pNew; - } -} - -/* -** Construct a new expression node for a function with multiple -** arguments. -*/ -Expr *sqlite3ExprFunction(Parse *pParse, ExprList *pList, Token *pToken){ - Expr *pNew; - sqlite3 *db = pParse->db; - assert( pToken ); - pNew = sqlite3ExprAlloc(db, TK_FUNCTION, pToken, 1); - if( pNew==0 ){ - sqlite3ExprListDelete(db, pList); /* Avoid memory leak when malloc fails */ - return 0; - } - pNew->x.pList = pList; - ExprSetProperty(pNew, EP_HasFunc); - assert( !ExprHasProperty(pNew, EP_xIsSelect) ); - sqlite3ExprSetHeightAndFlags(pParse, pNew); - return pNew; -} - -/* -** Assign a variable number to an expression that encodes a wildcard -** in the original SQL statement. -** -** Wildcards consisting of a single "?" are assigned the next sequential -** variable number. -** -** Wildcards of the form "?nnn" are assigned the number "nnn". We make -** sure "nnn" is not too big to avoid a denial of service attack when -** the SQL statement comes from an external source. -** -** Wildcards of the form ":aaa", "@aaa", or "$aaa" are assigned the same number -** as the previous instance of the same wildcard. Or if this is the first -** instance of the wildcard, the next sequential variable number is -** assigned. -*/ -void sqlite3ExprAssignVarNumber(Parse *pParse, Expr *pExpr, u32 n){ - sqlite3 *db = pParse->db; - const char *z; - ynVar x; - - if( pExpr==0 ) return; - assert( !ExprHasProperty(pExpr, EP_IntValue|EP_Reduced|EP_TokenOnly) ); - z = pExpr->u.zToken; - assert( z!=0 ); - assert( z[0]!=0 ); - assert( n==(u32)sqlite3Strlen30(z) ); - if( z[1]==0 ){ - /* Wildcard of the form "?". Assign the next variable number */ - assert( z[0]=='?' ); - x = (ynVar)(++pParse->nVar); - }else{ - int doAdd = 0; - if( z[0]=='?' ){ - /* Wildcard of the form "?nnn". Convert "nnn" to an integer and - ** use it as the variable number */ - i64 i; - int bOk; - if( n==2 ){ /*OPTIMIZATION-IF-TRUE*/ - i = z[1]-'0'; /* The common case of ?N for a single digit N */ - bOk = 1; - }else{ - bOk = 0==sqlite3Atoi64(&z[1], &i, n-1, SQLITE_UTF8); - } - testcase( i==0 ); - testcase( i==1 ); - testcase( i==db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER]-1 ); - testcase( i==db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] ); - if( bOk==0 || i<1 || i>db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] ){ - sqlite3ErrorMsg(pParse, "variable number must be between ?1 and ?%d", - db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER]); - return; - } - x = (ynVar)i; - if( x>pParse->nVar ){ - pParse->nVar = (int)x; - doAdd = 1; - }else if( sqlite3VListNumToName(pParse->pVList, x)==0 ){ - doAdd = 1; - } - }else{ - /* Wildcards like ":aaa", "$aaa" or "@aaa". Reuse the same variable - ** number as the prior appearance of the same name, or if the name - ** has never appeared before, reuse the same variable number - */ - x = (ynVar)sqlite3VListNameToNum(pParse->pVList, z, n); - if( x==0 ){ - x = (ynVar)(++pParse->nVar); - doAdd = 1; - } - } - if( doAdd ){ - pParse->pVList = sqlite3VListAdd(db, pParse->pVList, z, n, x); - } - } - pExpr->iColumn = x; - if( x>db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] ){ - sqlite3ErrorMsg(pParse, "too many SQL variables"); - } -} - -/* -** Recursively delete an expression tree. -*/ -static SQLITE_NOINLINE void sqlite3ExprDeleteNN(sqlite3 *db, Expr *p){ - assert( p!=0 ); - /* Sanity check: Assert that the IntValue is non-negative if it exists */ - assert( !ExprHasProperty(p, EP_IntValue) || p->u.iValue>=0 ); -#ifdef SQLITE_DEBUG - if( ExprHasProperty(p, EP_Leaf) && !ExprHasProperty(p, EP_TokenOnly) ){ - assert( p->pLeft==0 ); - assert( p->pRight==0 ); - assert( p->x.pSelect==0 ); - } -#endif - if( !ExprHasProperty(p, (EP_TokenOnly|EP_Leaf)) ){ - /* The Expr.x union is never used at the same time as Expr.pRight */ - assert( p->x.pList==0 || p->pRight==0 ); - if( p->pLeft && p->op!=TK_SELECT_COLUMN ) sqlite3ExprDeleteNN(db, p->pLeft); - if( p->pRight ){ - sqlite3ExprDeleteNN(db, p->pRight); - }else if( ExprHasProperty(p, EP_xIsSelect) ){ - sqlite3SelectDelete(db, p->x.pSelect); - }else{ - sqlite3ExprListDelete(db, p->x.pList); - } - } - if( ExprHasProperty(p, EP_MemToken) ) sqlite3DbFree(db, p->u.zToken); - if( !ExprHasProperty(p, EP_Static) ){ - sqlite3DbFreeNN(db, p); - } -} -void sqlite3ExprDelete(sqlite3 *db, Expr *p){ - if( p ) sqlite3ExprDeleteNN(db, p); -} - -/* -** Return the number of bytes allocated for the expression structure -** passed as the first argument. This is always one of EXPR_FULLSIZE, -** EXPR_REDUCEDSIZE or EXPR_TOKENONLYSIZE. -*/ -static int exprStructSize(Expr *p){ - if( ExprHasProperty(p, EP_TokenOnly) ) return EXPR_TOKENONLYSIZE; - if( ExprHasProperty(p, EP_Reduced) ) return EXPR_REDUCEDSIZE; - return EXPR_FULLSIZE; -} - -/* -** The dupedExpr*Size() routines each return the number of bytes required -** to store a copy of an expression or expression tree. They differ in -** how much of the tree is measured. -** -** dupedExprStructSize() Size of only the Expr structure -** dupedExprNodeSize() Size of Expr + space for token -** dupedExprSize() Expr + token + subtree components -** -*************************************************************************** -** -** The dupedExprStructSize() function returns two values OR-ed together: -** (1) the space required for a copy of the Expr structure only and -** (2) the EP_xxx flags that indicate what the structure size should be. -** The return values is always one of: -** -** EXPR_FULLSIZE -** EXPR_REDUCEDSIZE | EP_Reduced -** EXPR_TOKENONLYSIZE | EP_TokenOnly -** -** The size of the structure can be found by masking the return value -** of this routine with 0xfff. The flags can be found by masking the -** return value with EP_Reduced|EP_TokenOnly. -** -** Note that with flags==EXPRDUP_REDUCE, this routines works on full-size -** (unreduced) Expr objects as they or originally constructed by the parser. -** During expression analysis, extra information is computed and moved into -** later parts of teh Expr object and that extra information might get chopped -** off if the expression is reduced. Note also that it does not work to -** make an EXPRDUP_REDUCE copy of a reduced expression. It is only legal -** to reduce a pristine expression tree from the parser. The implementation -** of dupedExprStructSize() contain multiple assert() statements that attempt -** to enforce this constraint. -*/ -static int dupedExprStructSize(Expr *p, int flags){ - int nSize; - assert( flags==EXPRDUP_REDUCE || flags==0 ); /* Only one flag value allowed */ - assert( EXPR_FULLSIZE<=0xfff ); - assert( (0xfff & (EP_Reduced|EP_TokenOnly))==0 ); - if( 0==flags || p->op==TK_SELECT_COLUMN ){ - nSize = EXPR_FULLSIZE; - }else{ - assert( !ExprHasProperty(p, EP_TokenOnly|EP_Reduced) ); - assert( !ExprHasProperty(p, EP_FromJoin) ); - assert( !ExprHasProperty(p, EP_MemToken) ); - assert( !ExprHasProperty(p, EP_NoReduce) ); - if( p->pLeft || p->x.pList ){ - nSize = EXPR_REDUCEDSIZE | EP_Reduced; - }else{ - assert( p->pRight==0 ); - nSize = EXPR_TOKENONLYSIZE | EP_TokenOnly; - } - } - return nSize; -} - -/* -** This function returns the space in bytes required to store the copy -** of the Expr structure and a copy of the Expr.u.zToken string (if that -** string is defined.) -*/ -static int dupedExprNodeSize(Expr *p, int flags){ - int nByte = dupedExprStructSize(p, flags) & 0xfff; - if( !ExprHasProperty(p, EP_IntValue) && p->u.zToken ){ - nByte += sqlite3Strlen30(p->u.zToken)+1; - } - return ROUND8(nByte); -} - -/* -** Return the number of bytes required to create a duplicate of the -** expression passed as the first argument. The second argument is a -** mask containing EXPRDUP_XXX flags. -** -** The value returned includes space to create a copy of the Expr struct -** itself and the buffer referred to by Expr.u.zToken, if any. -** -** If the EXPRDUP_REDUCE flag is set, then the return value includes -** space to duplicate all Expr nodes in the tree formed by Expr.pLeft -** and Expr.pRight variables (but not for any structures pointed to or -** descended from the Expr.x.pList or Expr.x.pSelect variables). -*/ -static int dupedExprSize(Expr *p, int flags){ - int nByte = 0; - if( p ){ - nByte = dupedExprNodeSize(p, flags); - if( flags&EXPRDUP_REDUCE ){ - nByte += dupedExprSize(p->pLeft, flags) + dupedExprSize(p->pRight, flags); - } - } - return nByte; -} - -/* -** This function is similar to sqlite3ExprDup(), except that if pzBuffer -** is not NULL then *pzBuffer is assumed to point to a buffer large enough -** to store the copy of expression p, the copies of p->u.zToken -** (if applicable), and the copies of the p->pLeft and p->pRight expressions, -** if any. Before returning, *pzBuffer is set to the first byte past the -** portion of the buffer copied into by this function. -*/ -static Expr *exprDup(sqlite3 *db, Expr *p, int dupFlags, u8 **pzBuffer){ - Expr *pNew; /* Value to return */ - u8 *zAlloc; /* Memory space from which to build Expr object */ - u32 staticFlag; /* EP_Static if space not obtained from malloc */ - - assert( db!=0 ); - assert( p ); - assert( dupFlags==0 || dupFlags==EXPRDUP_REDUCE ); - assert( pzBuffer==0 || dupFlags==EXPRDUP_REDUCE ); - - /* Figure out where to write the new Expr structure. */ - if( pzBuffer ){ - zAlloc = *pzBuffer; - staticFlag = EP_Static; - }else{ - zAlloc = sqlite3DbMallocRawNN(db, dupedExprSize(p, dupFlags)); - staticFlag = 0; - } - pNew = (Expr *)zAlloc; - - if( pNew ){ - /* Set nNewSize to the size allocated for the structure pointed to - ** by pNew. This is either EXPR_FULLSIZE, EXPR_REDUCEDSIZE or - ** EXPR_TOKENONLYSIZE. nToken is set to the number of bytes consumed - ** by the copy of the p->u.zToken string (if any). - */ - const unsigned nStructSize = dupedExprStructSize(p, dupFlags); - const int nNewSize = nStructSize & 0xfff; - int nToken; - if( !ExprHasProperty(p, EP_IntValue) && p->u.zToken ){ - nToken = sqlite3Strlen30(p->u.zToken) + 1; - }else{ - nToken = 0; - } - if( dupFlags ){ - assert( ExprHasProperty(p, EP_Reduced)==0 ); - memcpy(zAlloc, p, nNewSize); - }else{ - u32 nSize = (u32)exprStructSize(p); - memcpy(zAlloc, p, nSize); - if( nSize<EXPR_FULLSIZE ){ - memset(&zAlloc[nSize], 0, EXPR_FULLSIZE-nSize); - } - } - - /* Set the EP_Reduced, EP_TokenOnly, and EP_Static flags appropriately. */ - pNew->flags &= ~(EP_Reduced|EP_TokenOnly|EP_Static|EP_MemToken); - pNew->flags |= nStructSize & (EP_Reduced|EP_TokenOnly); - pNew->flags |= staticFlag; - - /* Copy the p->u.zToken string, if any. */ - if( nToken ){ - char *zToken = pNew->u.zToken = (char*)&zAlloc[nNewSize]; - memcpy(zToken, p->u.zToken, nToken); - } - - if( 0==((p->flags|pNew->flags) & (EP_TokenOnly|EP_Leaf)) ){ - /* Fill in the pNew->x.pSelect or pNew->x.pList member. */ - if( ExprHasProperty(p, EP_xIsSelect) ){ - pNew->x.pSelect = sqlite3SelectDup(db, p->x.pSelect, dupFlags); - }else{ - pNew->x.pList = sqlite3ExprListDup(db, p->x.pList, dupFlags); - } - } - - /* Fill in pNew->pLeft and pNew->pRight. */ - if( ExprHasProperty(pNew, EP_Reduced|EP_TokenOnly) ){ - zAlloc += dupedExprNodeSize(p, dupFlags); - if( !ExprHasProperty(pNew, EP_TokenOnly|EP_Leaf) ){ - pNew->pLeft = p->pLeft ? - exprDup(db, p->pLeft, EXPRDUP_REDUCE, &zAlloc) : 0; - pNew->pRight = p->pRight ? - exprDup(db, p->pRight, EXPRDUP_REDUCE, &zAlloc) : 0; - } - if( pzBuffer ){ - *pzBuffer = zAlloc; - } - }else{ - if( !ExprHasProperty(p, EP_TokenOnly|EP_Leaf) ){ - if( pNew->op==TK_SELECT_COLUMN ){ - pNew->pLeft = p->pLeft; - assert( p->iColumn==0 || p->pRight==0 ); - assert( p->pRight==0 || p->pRight==p->pLeft ); - }else{ - pNew->pLeft = sqlite3ExprDup(db, p->pLeft, 0); - } - pNew->pRight = sqlite3ExprDup(db, p->pRight, 0); - } - } - } - return pNew; -} - -/* -** Create and return a deep copy of the object passed as the second -** argument. If an OOM condition is encountered, NULL is returned -** and the db->mallocFailed flag set. -*/ -#ifndef SQLITE_OMIT_CTE -static With *withDup(sqlite3 *db, With *p){ - With *pRet = 0; - if( p ){ - int nByte = sizeof(*p) + sizeof(p->a[0]) * (p->nCte-1); - pRet = sqlite3DbMallocZero(db, nByte); - if( pRet ){ - int i; - pRet->nCte = p->nCte; - for(i=0; i<p->nCte; i++){ - pRet->a[i].pSelect = sqlite3SelectDup(db, p->a[i].pSelect, 0); - pRet->a[i].pCols = sqlite3ExprListDup(db, p->a[i].pCols, 0); - pRet->a[i].zName = sqlite3DbStrDup(db, p->a[i].zName); - } - } - } - return pRet; -} -#else -# define withDup(x,y) 0 -#endif - -/* -** The following group of routines make deep copies of expressions, -** expression lists, ID lists, and select statements. The copies can -** be deleted (by being passed to their respective ...Delete() routines) -** without effecting the originals. -** -** The expression list, ID, and source lists return by sqlite3ExprListDup(), -** sqlite3IdListDup(), and sqlite3SrcListDup() can not be further expanded -** by subsequent calls to sqlite*ListAppend() routines. -** -** Any tables that the SrcList might point to are not duplicated. -** -** The flags parameter contains a combination of the EXPRDUP_XXX flags. -** If the EXPRDUP_REDUCE flag is set, then the structure returned is a -** truncated version of the usual Expr structure that will be stored as -** part of the in-memory representation of the database schema. -*/ -Expr *sqlite3ExprDup(sqlite3 *db, Expr *p, int flags){ - assert( flags==0 || flags==EXPRDUP_REDUCE ); - return p ? exprDup(db, p, flags, 0) : 0; -} -ExprList *sqlite3ExprListDup(sqlite3 *db, ExprList *p, int flags){ - ExprList *pNew; - struct ExprList_item *pItem, *pOldItem; - int i; - Expr *pPriorSelectCol = 0; - assert( db!=0 ); - if( p==0 ) return 0; - pNew = sqlite3DbMallocRawNN(db, sqlite3DbMallocSize(db, p)); - if( pNew==0 ) return 0; - pNew->nExpr = p->nExpr; - pItem = pNew->a; - pOldItem = p->a; - for(i=0; i<p->nExpr; i++, pItem++, pOldItem++){ - Expr *pOldExpr = pOldItem->pExpr; - Expr *pNewExpr; - pItem->pExpr = sqlite3ExprDup(db, pOldExpr, flags); - if( pOldExpr - && pOldExpr->op==TK_SELECT_COLUMN - && (pNewExpr = pItem->pExpr)!=0 - ){ - assert( pNewExpr->iColumn==0 || i>0 ); - if( pNewExpr->iColumn==0 ){ - assert( pOldExpr->pLeft==pOldExpr->pRight ); - pPriorSelectCol = pNewExpr->pLeft = pNewExpr->pRight; - }else{ - assert( i>0 ); - assert( pItem[-1].pExpr!=0 ); - assert( pNewExpr->iColumn==pItem[-1].pExpr->iColumn+1 ); - assert( pPriorSelectCol==pItem[-1].pExpr->pLeft ); - pNewExpr->pLeft = pPriorSelectCol; - } - } - pItem->zName = sqlite3DbStrDup(db, pOldItem->zName); - pItem->zSpan = sqlite3DbStrDup(db, pOldItem->zSpan); - pItem->sortOrder = pOldItem->sortOrder; - pItem->done = 0; - pItem->bSpanIsTab = pOldItem->bSpanIsTab; - pItem->bSorterRef = pOldItem->bSorterRef; - pItem->u = pOldItem->u; - } - return pNew; -} - -/* -** If cursors, triggers, views and subqueries are all omitted from -** the build, then none of the following routines, except for -** sqlite3SelectDup(), can be called. sqlite3SelectDup() is sometimes -** called with a NULL argument. -*/ -#if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_TRIGGER) \ - || !defined(SQLITE_OMIT_SUBQUERY) -SrcList *sqlite3SrcListDup(sqlite3 *db, SrcList *p, int flags){ - SrcList *pNew; - int i; - int nByte; - assert( db!=0 ); - if( p==0 ) return 0; - nByte = sizeof(*p) + (p->nSrc>0 ? sizeof(p->a[0]) * (p->nSrc-1) : 0); - pNew = sqlite3DbMallocRawNN(db, nByte ); - if( pNew==0 ) return 0; - pNew->nSrc = pNew->nAlloc = p->nSrc; - for(i=0; i<p->nSrc; i++){ - struct SrcList_item *pNewItem = &pNew->a[i]; - struct SrcList_item *pOldItem = &p->a[i]; - Table *pTab; - pNewItem->pSchema = pOldItem->pSchema; - pNewItem->zDatabase = sqlite3DbStrDup(db, pOldItem->zDatabase); - pNewItem->zName = sqlite3DbStrDup(db, pOldItem->zName); - pNewItem->zAlias = sqlite3DbStrDup(db, pOldItem->zAlias); - pNewItem->fg = pOldItem->fg; - pNewItem->iCursor = pOldItem->iCursor; - pNewItem->addrFillSub = pOldItem->addrFillSub; - pNewItem->regReturn = pOldItem->regReturn; - if( pNewItem->fg.isIndexedBy ){ - pNewItem->u1.zIndexedBy = sqlite3DbStrDup(db, pOldItem->u1.zIndexedBy); - } - pNewItem->pIBIndex = pOldItem->pIBIndex; - if( pNewItem->fg.isTabFunc ){ - pNewItem->u1.pFuncArg = - sqlite3ExprListDup(db, pOldItem->u1.pFuncArg, flags); - } - pTab = pNewItem->pTab = pOldItem->pTab; - if( pTab ){ - pTab->nTabRef++; - } - pNewItem->pSelect = sqlite3SelectDup(db, pOldItem->pSelect, flags); - pNewItem->pOn = sqlite3ExprDup(db, pOldItem->pOn, flags); - pNewItem->pUsing = sqlite3IdListDup(db, pOldItem->pUsing); - pNewItem->colUsed = pOldItem->colUsed; - } - return pNew; -} -IdList *sqlite3IdListDup(sqlite3 *db, IdList *p){ - IdList *pNew; - int i; - assert( db!=0 ); - if( p==0 ) return 0; - pNew = sqlite3DbMallocRawNN(db, sizeof(*pNew) ); - if( pNew==0 ) return 0; - pNew->nId = p->nId; - pNew->a = sqlite3DbMallocRawNN(db, p->nId*sizeof(p->a[0]) ); - if( pNew->a==0 ){ - sqlite3DbFreeNN(db, pNew); - return 0; - } - /* Note that because the size of the allocation for p->a[] is not - ** necessarily a power of two, sqlite3IdListAppend() may not be called - ** on the duplicate created by this function. */ - for(i=0; i<p->nId; i++){ - struct IdList_item *pNewItem = &pNew->a[i]; - struct IdList_item *pOldItem = &p->a[i]; - pNewItem->zName = sqlite3DbStrDup(db, pOldItem->zName); - pNewItem->idx = pOldItem->idx; - } - return pNew; -} -Select *sqlite3SelectDup(sqlite3 *db, Select *pDup, int flags){ - Select *pRet = 0; - Select *pNext = 0; - Select **pp = &pRet; - Select *p; - - assert( db!=0 ); - for(p=pDup; p; p=p->pPrior){ - Select *pNew = sqlite3DbMallocRawNN(db, sizeof(*p) ); - if( pNew==0 ) break; - pNew->pEList = sqlite3ExprListDup(db, p->pEList, flags); - pNew->pSrc = sqlite3SrcListDup(db, p->pSrc, flags); - pNew->pWhere = sqlite3ExprDup(db, p->pWhere, flags); - pNew->pGroupBy = sqlite3ExprListDup(db, p->pGroupBy, flags); - pNew->pHaving = sqlite3ExprDup(db, p->pHaving, flags); - pNew->pOrderBy = sqlite3ExprListDup(db, p->pOrderBy, flags); - pNew->op = p->op; - pNew->pNext = pNext; - pNew->pPrior = 0; - pNew->pLimit = sqlite3ExprDup(db, p->pLimit, flags); - pNew->iLimit = 0; - pNew->iOffset = 0; - pNew->selFlags = p->selFlags & ~SF_UsesEphemeral; - pNew->addrOpenEphm[0] = -1; - pNew->addrOpenEphm[1] = -1; - pNew->nSelectRow = p->nSelectRow; - pNew->pWith = withDup(db, p->pWith); - sqlite3SelectSetName(pNew, p->zSelName); - *pp = pNew; - pp = &pNew->pPrior; - pNext = pNew; - } - - return pRet; -} -#else -Select *sqlite3SelectDup(sqlite3 *db, Select *p, int flags){ - assert( p==0 ); - return 0; -} -#endif - - -/* -** Add a new element to the end of an expression list. If pList is -** initially NULL, then create a new expression list. -** -** The pList argument must be either NULL or a pointer to an ExprList -** obtained from a prior call to sqlite3ExprListAppend(). This routine -** may not be used with an ExprList obtained from sqlite3ExprListDup(). -** Reason: This routine assumes that the number of slots in pList->a[] -** is a power of two. That is true for sqlite3ExprListAppend() returns -** but is not necessarily true from the return value of sqlite3ExprListDup(). -** -** If a memory allocation error occurs, the entire list is freed and -** NULL is returned. If non-NULL is returned, then it is guaranteed -** that the new entry was successfully appended. -*/ -ExprList *sqlite3ExprListAppend( - Parse *pParse, /* Parsing context */ - ExprList *pList, /* List to which to append. Might be NULL */ - Expr *pExpr /* Expression to be appended. Might be NULL */ -){ - struct ExprList_item *pItem; - sqlite3 *db = pParse->db; - assert( db!=0 ); - if( pList==0 ){ - pList = sqlite3DbMallocRawNN(db, sizeof(ExprList) ); - if( pList==0 ){ - goto no_mem; - } - pList->nExpr = 0; - }else if( (pList->nExpr & (pList->nExpr-1))==0 ){ - ExprList *pNew; - pNew = sqlite3DbRealloc(db, pList, - sizeof(*pList)+(2*pList->nExpr - 1)*sizeof(pList->a[0])); - if( pNew==0 ){ - goto no_mem; - } - pList = pNew; - } - pItem = &pList->a[pList->nExpr++]; - assert( offsetof(struct ExprList_item,zName)==sizeof(pItem->pExpr) ); - assert( offsetof(struct ExprList_item,pExpr)==0 ); - memset(&pItem->zName,0,sizeof(*pItem)-offsetof(struct ExprList_item,zName)); - pItem->pExpr = pExpr; - return pList; - -no_mem: - /* Avoid leaking memory if malloc has failed. */ - sqlite3ExprDelete(db, pExpr); - sqlite3ExprListDelete(db, pList); - return 0; -} - -/* -** pColumns and pExpr form a vector assignment which is part of the SET -** clause of an UPDATE statement. Like this: -** -** (a,b,c) = (expr1,expr2,expr3) -** Or: (a,b,c) = (SELECT x,y,z FROM ....) -** -** For each term of the vector assignment, append new entries to the -** expression list pList. In the case of a subquery on the RHS, append -** TK_SELECT_COLUMN expressions. -*/ -ExprList *sqlite3ExprListAppendVector( - Parse *pParse, /* Parsing context */ - ExprList *pList, /* List to which to append. Might be NULL */ - IdList *pColumns, /* List of names of LHS of the assignment */ - Expr *pExpr /* Vector expression to be appended. Might be NULL */ -){ - sqlite3 *db = pParse->db; - int n; - int i; - int iFirst = pList ? pList->nExpr : 0; - /* pColumns can only be NULL due to an OOM but an OOM will cause an - ** exit prior to this routine being invoked */ - if( NEVER(pColumns==0) ) goto vector_append_error; - if( pExpr==0 ) goto vector_append_error; - - /* If the RHS is a vector, then we can immediately check to see that - ** the size of the RHS and LHS match. But if the RHS is a SELECT, - ** wildcards ("*") in the result set of the SELECT must be expanded before - ** we can do the size check, so defer the size check until code generation. - */ - if( pExpr->op!=TK_SELECT && pColumns->nId!=(n=sqlite3ExprVectorSize(pExpr)) ){ - sqlite3ErrorMsg(pParse, "%d columns assigned %d values", - pColumns->nId, n); - goto vector_append_error; - } - - for(i=0; i<pColumns->nId; i++){ - Expr *pSubExpr = sqlite3ExprForVectorField(pParse, pExpr, i); - pList = sqlite3ExprListAppend(pParse, pList, pSubExpr); - if( pList ){ - assert( pList->nExpr==iFirst+i+1 ); - pList->a[pList->nExpr-1].zName = pColumns->a[i].zName; - pColumns->a[i].zName = 0; - } - } - - if( !db->mallocFailed && pExpr->op==TK_SELECT && ALWAYS(pList!=0) ){ - Expr *pFirst = pList->a[iFirst].pExpr; - assert( pFirst!=0 ); - assert( pFirst->op==TK_SELECT_COLUMN ); - - /* Store the SELECT statement in pRight so it will be deleted when - ** sqlite3ExprListDelete() is called */ - pFirst->pRight = pExpr; - pExpr = 0; - - /* Remember the size of the LHS in iTable so that we can check that - ** the RHS and LHS sizes match during code generation. */ - pFirst->iTable = pColumns->nId; - } - -vector_append_error: - sqlite3ExprDelete(db, pExpr); - sqlite3IdListDelete(db, pColumns); - return pList; -} - -/* -** Set the sort order for the last element on the given ExprList. -*/ -void sqlite3ExprListSetSortOrder(ExprList *p, int iSortOrder){ - if( p==0 ) return; - assert( SQLITE_SO_UNDEFINED<0 && SQLITE_SO_ASC>=0 && SQLITE_SO_DESC>0 ); - assert( p->nExpr>0 ); - if( iSortOrder<0 ){ - assert( p->a[p->nExpr-1].sortOrder==SQLITE_SO_ASC ); - return; - } - p->a[p->nExpr-1].sortOrder = (u8)iSortOrder; -} - -/* -** Set the ExprList.a[].zName element of the most recently added item -** on the expression list. -** -** pList might be NULL following an OOM error. But pName should never be -** NULL. If a memory allocation fails, the pParse->db->mallocFailed flag -** is set. -*/ -void sqlite3ExprListSetName( - Parse *pParse, /* Parsing context */ - ExprList *pList, /* List to which to add the span. */ - Token *pName, /* Name to be added */ - int dequote /* True to cause the name to be dequoted */ -){ - assert( pList!=0 || pParse->db->mallocFailed!=0 ); - if( pList ){ - struct ExprList_item *pItem; - assert( pList->nExpr>0 ); - pItem = &pList->a[pList->nExpr-1]; - assert( pItem->zName==0 ); - pItem->zName = sqlite3DbStrNDup(pParse->db, pName->z, pName->n); - if( dequote ) sqlite3Dequote(pItem->zName); - } -} - -/* -** Set the ExprList.a[].zSpan element of the most recently added item -** on the expression list. -** -** pList might be NULL following an OOM error. But pSpan should never be -** NULL. If a memory allocation fails, the pParse->db->mallocFailed flag -** is set. -*/ -void sqlite3ExprListSetSpan( - Parse *pParse, /* Parsing context */ - ExprList *pList, /* List to which to add the span. */ - const char *zStart, /* Start of the span */ - const char *zEnd /* End of the span */ -){ - sqlite3 *db = pParse->db; - assert( pList!=0 || db->mallocFailed!=0 ); - if( pList ){ - struct ExprList_item *pItem = &pList->a[pList->nExpr-1]; - assert( pList->nExpr>0 ); - sqlite3DbFree(db, pItem->zSpan); - pItem->zSpan = sqlite3DbSpanDup(db, zStart, zEnd); - } -} - -/* -** If the expression list pEList contains more than iLimit elements, -** leave an error message in pParse. -*/ -void sqlite3ExprListCheckLength( - Parse *pParse, - ExprList *pEList, - const char *zObject -){ - int mx = pParse->db->aLimit[SQLITE_LIMIT_COLUMN]; - testcase( pEList && pEList->nExpr==mx ); - testcase( pEList && pEList->nExpr==mx+1 ); - if( pEList && pEList->nExpr>mx ){ - sqlite3ErrorMsg(pParse, "too many columns in %s", zObject); - } -} - -/* -** Delete an entire expression list. -*/ -static SQLITE_NOINLINE void exprListDeleteNN(sqlite3 *db, ExprList *pList){ - int i = pList->nExpr; - struct ExprList_item *pItem = pList->a; - assert( pList->nExpr>0 ); - do{ - sqlite3ExprDelete(db, pItem->pExpr); - sqlite3DbFree(db, pItem->zName); - sqlite3DbFree(db, pItem->zSpan); - pItem++; - }while( --i>0 ); - sqlite3DbFreeNN(db, pList); -} -void sqlite3ExprListDelete(sqlite3 *db, ExprList *pList){ - if( pList ) exprListDeleteNN(db, pList); -} - -/* -** Return the bitwise-OR of all Expr.flags fields in the given -** ExprList. -*/ -u32 sqlite3ExprListFlags(const ExprList *pList){ - int i; - u32 m = 0; - assert( pList!=0 ); - for(i=0; i<pList->nExpr; i++){ - Expr *pExpr = pList->a[i].pExpr; - assert( pExpr!=0 ); - m |= pExpr->flags; - } - return m; -} - -/* -** This is a SELECT-node callback for the expression walker that -** always "fails". By "fail" in this case, we mean set -** pWalker->eCode to zero and abort. -** -** This callback is used by multiple expression walkers. -*/ -int sqlite3SelectWalkFail(Walker *pWalker, Select *NotUsed){ - UNUSED_PARAMETER(NotUsed); - pWalker->eCode = 0; - return WRC_Abort; -} - -/* -** If the input expression is an ID with the name "true" or "false" -** then convert it into an TK_TRUEFALSE term. Return non-zero if -** the conversion happened, and zero if the expression is unaltered. -*/ -int sqlite3ExprIdToTrueFalse(Expr *pExpr){ - assert( pExpr->op==TK_ID || pExpr->op==TK_STRING ); - if( sqlite3StrICmp(pExpr->u.zToken, "true")==0 - || sqlite3StrICmp(pExpr->u.zToken, "false")==0 - ){ - pExpr->op = TK_TRUEFALSE; - return 1; - } - return 0; -} - -/* -** The argument must be a TK_TRUEFALSE Expr node. Return 1 if it is TRUE -** and 0 if it is FALSE. -*/ -int sqlite3ExprTruthValue(const Expr *pExpr){ - assert( pExpr->op==TK_TRUEFALSE ); - assert( sqlite3StrICmp(pExpr->u.zToken,"true")==0 - || sqlite3StrICmp(pExpr->u.zToken,"false")==0 ); - return pExpr->u.zToken[4]==0; -} - - -/* -** These routines are Walker callbacks used to check expressions to -** see if they are "constant" for some definition of constant. The -** Walker.eCode value determines the type of "constant" we are looking -** for. -** -** These callback routines are used to implement the following: -** -** sqlite3ExprIsConstant() pWalker->eCode==1 -** sqlite3ExprIsConstantNotJoin() pWalker->eCode==2 -** sqlite3ExprIsTableConstant() pWalker->eCode==3 -** sqlite3ExprIsConstantOrFunction() pWalker->eCode==4 or 5 -** -** In all cases, the callbacks set Walker.eCode=0 and abort if the expression -** is found to not be a constant. -** -** The sqlite3ExprIsConstantOrFunction() is used for evaluating expressions -** in a CREATE TABLE statement. The Walker.eCode value is 5 when parsing -** an existing schema and 4 when processing a new statement. A bound -** parameter raises an error for new statements, but is silently converted -** to NULL for existing schemas. This allows sqlite_master tables that -** contain a bound parameter because they were generated by older versions -** of SQLite to be parsed by newer versions of SQLite without raising a -** malformed schema error. -*/ -static int exprNodeIsConstant(Walker *pWalker, Expr *pExpr){ - - /* If pWalker->eCode is 2 then any term of the expression that comes from - ** the ON or USING clauses of a left join disqualifies the expression - ** from being considered constant. */ - if( pWalker->eCode==2 && ExprHasProperty(pExpr, EP_FromJoin) ){ - pWalker->eCode = 0; - return WRC_Abort; - } - - switch( pExpr->op ){ - /* Consider functions to be constant if all their arguments are constant - ** and either pWalker->eCode==4 or 5 or the function has the - ** SQLITE_FUNC_CONST flag. */ - case TK_FUNCTION: - if( pWalker->eCode>=4 || ExprHasProperty(pExpr,EP_ConstFunc) ){ - return WRC_Continue; - }else{ - pWalker->eCode = 0; - return WRC_Abort; - } - case TK_ID: - /* Convert "true" or "false" in a DEFAULT clause into the - ** appropriate TK_TRUEFALSE operator */ - if( sqlite3ExprIdToTrueFalse(pExpr) ){ - return WRC_Prune; - } - /* Fall thru */ - case TK_COLUMN: - case TK_AGG_FUNCTION: - case TK_AGG_COLUMN: - testcase( pExpr->op==TK_ID ); - testcase( pExpr->op==TK_COLUMN ); - testcase( pExpr->op==TK_AGG_FUNCTION ); - testcase( pExpr->op==TK_AGG_COLUMN ); - if( pWalker->eCode==3 && pExpr->iTable==pWalker->u.iCur ){ - return WRC_Continue; - } - /* Fall through */ - case TK_IF_NULL_ROW: - case TK_REGISTER: - testcase( pExpr->op==TK_REGISTER ); - testcase( pExpr->op==TK_IF_NULL_ROW ); - pWalker->eCode = 0; - return WRC_Abort; - case TK_VARIABLE: - if( pWalker->eCode==5 ){ - /* Silently convert bound parameters that appear inside of CREATE - ** statements into a NULL when parsing the CREATE statement text out - ** of the sqlite_master table */ - pExpr->op = TK_NULL; - }else if( pWalker->eCode==4 ){ - /* A bound parameter in a CREATE statement that originates from - ** sqlite3_prepare() causes an error */ - pWalker->eCode = 0; - return WRC_Abort; - } - /* Fall through */ - default: - testcase( pExpr->op==TK_SELECT ); /* sqlite3SelectWalkFail() disallows */ - testcase( pExpr->op==TK_EXISTS ); /* sqlite3SelectWalkFail() disallows */ - return WRC_Continue; - } -} -static int exprIsConst(Expr *p, int initFlag, int iCur){ - Walker w; - w.eCode = initFlag; - w.xExprCallback = exprNodeIsConstant; - w.xSelectCallback = sqlite3SelectWalkFail; -#ifdef SQLITE_DEBUG - w.xSelectCallback2 = sqlite3SelectWalkAssert2; -#endif - w.u.iCur = iCur; - sqlite3WalkExpr(&w, p); - return w.eCode; -} - -/* -** Walk an expression tree. Return non-zero if the expression is constant -** and 0 if it involves variables or function calls. -** -** For the purposes of this function, a double-quoted string (ex: "abc") -** is considered a variable but a single-quoted string (ex: 'abc') is -** a constant. -*/ -int sqlite3ExprIsConstant(Expr *p){ - return exprIsConst(p, 1, 0); -} - -/* -** Walk an expression tree. Return non-zero if the expression is constant -** that does no originate from the ON or USING clauses of a join. -** Return 0 if it involves variables or function calls or terms from -** an ON or USING clause. -*/ -int sqlite3ExprIsConstantNotJoin(Expr *p){ - return exprIsConst(p, 2, 0); -} - -/* -** Walk an expression tree. Return non-zero if the expression is constant -** for any single row of the table with cursor iCur. In other words, the -** expression must not refer to any non-deterministic function nor any -** table other than iCur. -*/ -int sqlite3ExprIsTableConstant(Expr *p, int iCur){ - return exprIsConst(p, 3, iCur); -} - - -/* -** sqlite3WalkExpr() callback used by sqlite3ExprIsConstantOrGroupBy(). -*/ -static int exprNodeIsConstantOrGroupBy(Walker *pWalker, Expr *pExpr){ - ExprList *pGroupBy = pWalker->u.pGroupBy; - int i; - - /* Check if pExpr is identical to any GROUP BY term. If so, consider - ** it constant. */ - for(i=0; i<pGroupBy->nExpr; i++){ - Expr *p = pGroupBy->a[i].pExpr; - if( sqlite3ExprCompare(0, pExpr, p, -1)<2 ){ - CollSeq *pColl = sqlite3ExprNNCollSeq(pWalker->pParse, p); - if( sqlite3_stricmp("BINARY", pColl->zName)==0 ){ - return WRC_Prune; - } - } - } - - /* Check if pExpr is a sub-select. If so, consider it variable. */ - if( ExprHasProperty(pExpr, EP_xIsSelect) ){ - pWalker->eCode = 0; - return WRC_Abort; - } - - return exprNodeIsConstant(pWalker, pExpr); -} - -/* -** Walk the expression tree passed as the first argument. Return non-zero -** if the expression consists entirely of constants or copies of terms -** in pGroupBy that sort with the BINARY collation sequence. -** -** This routine is used to determine if a term of the HAVING clause can -** be promoted into the WHERE clause. In order for such a promotion to work, -** the value of the HAVING clause term must be the same for all members of -** a "group". The requirement that the GROUP BY term must be BINARY -** assumes that no other collating sequence will have a finer-grained -** grouping than binary. In other words (A=B COLLATE binary) implies -** A=B in every other collating sequence. The requirement that the -** GROUP BY be BINARY is stricter than necessary. It would also work -** to promote HAVING clauses that use the same alternative collating -** sequence as the GROUP BY term, but that is much harder to check, -** alternative collating sequences are uncommon, and this is only an -** optimization, so we take the easy way out and simply require the -** GROUP BY to use the BINARY collating sequence. -*/ -int sqlite3ExprIsConstantOrGroupBy(Parse *pParse, Expr *p, ExprList *pGroupBy){ - Walker w; - w.eCode = 1; - w.xExprCallback = exprNodeIsConstantOrGroupBy; - w.xSelectCallback = 0; - w.u.pGroupBy = pGroupBy; - w.pParse = pParse; - sqlite3WalkExpr(&w, p); - return w.eCode; -} - -/* -** Walk an expression tree. Return non-zero if the expression is constant -** or a function call with constant arguments. Return and 0 if there -** are any variables. -** -** For the purposes of this function, a double-quoted string (ex: "abc") -** is considered a variable but a single-quoted string (ex: 'abc') is -** a constant. -*/ -int sqlite3ExprIsConstantOrFunction(Expr *p, u8 isInit){ - assert( isInit==0 || isInit==1 ); - return exprIsConst(p, 4+isInit, 0); -} - -#ifdef SQLITE_ENABLE_CURSOR_HINTS -/* -** Walk an expression tree. Return 1 if the expression contains a -** subquery of some kind. Return 0 if there are no subqueries. -*/ -int sqlite3ExprContainsSubquery(Expr *p){ - Walker w; - w.eCode = 1; - w.xExprCallback = sqlite3ExprWalkNoop; - w.xSelectCallback = sqlite3SelectWalkFail; -#ifdef SQLITE_DEBUG - w.xSelectCallback2 = sqlite3SelectWalkAssert2; -#endif - sqlite3WalkExpr(&w, p); - return w.eCode==0; -} -#endif - -/* -** If the expression p codes a constant integer that is small enough -** to fit in a 32-bit integer, return 1 and put the value of the integer -** in *pValue. If the expression is not an integer or if it is too big -** to fit in a signed 32-bit integer, return 0 and leave *pValue unchanged. -*/ -int sqlite3ExprIsInteger(Expr *p, int *pValue){ - int rc = 0; - if( p==0 ) return 0; /* Can only happen following on OOM */ - - /* If an expression is an integer literal that fits in a signed 32-bit - ** integer, then the EP_IntValue flag will have already been set */ - assert( p->op!=TK_INTEGER || (p->flags & EP_IntValue)!=0 - || sqlite3GetInt32(p->u.zToken, &rc)==0 ); - - if( p->flags & EP_IntValue ){ - *pValue = p->u.iValue; - return 1; - } - switch( p->op ){ - case TK_UPLUS: { - rc = sqlite3ExprIsInteger(p->pLeft, pValue); - break; - } - case TK_UMINUS: { - int v; - if( sqlite3ExprIsInteger(p->pLeft, &v) ){ - assert( v!=(-2147483647-1) ); - *pValue = -v; - rc = 1; - } - break; - } - default: break; - } - return rc; -} - -/* -** Return FALSE if there is no chance that the expression can be NULL. -** -** If the expression might be NULL or if the expression is too complex -** to tell return TRUE. -** -** This routine is used as an optimization, to skip OP_IsNull opcodes -** when we know that a value cannot be NULL. Hence, a false positive -** (returning TRUE when in fact the expression can never be NULL) might -** be a small performance hit but is otherwise harmless. On the other -** hand, a false negative (returning FALSE when the result could be NULL) -** will likely result in an incorrect answer. So when in doubt, return -** TRUE. -*/ -int sqlite3ExprCanBeNull(const Expr *p){ - u8 op; - while( p->op==TK_UPLUS || p->op==TK_UMINUS ){ p = p->pLeft; } - op = p->op; - if( op==TK_REGISTER ) op = p->op2; - switch( op ){ - case TK_INTEGER: - case TK_STRING: - case TK_FLOAT: - case TK_BLOB: - return 0; - case TK_COLUMN: - return ExprHasProperty(p, EP_CanBeNull) || - p->pTab==0 || /* Reference to column of index on expression */ - (p->iColumn>=0 && p->pTab->aCol[p->iColumn].notNull==0); - default: - return 1; - } -} - -/* -** Return TRUE if the given expression is a constant which would be -** unchanged by OP_Affinity with the affinity given in the second -** argument. -** -** This routine is used to determine if the OP_Affinity operation -** can be omitted. When in doubt return FALSE. A false negative -** is harmless. A false positive, however, can result in the wrong -** answer. -*/ -int sqlite3ExprNeedsNoAffinityChange(const Expr *p, char aff){ - u8 op; - if( aff==SQLITE_AFF_BLOB ) return 1; - while( p->op==TK_UPLUS || p->op==TK_UMINUS ){ p = p->pLeft; } - op = p->op; - if( op==TK_REGISTER ) op = p->op2; - switch( op ){ - case TK_INTEGER: { - return aff==SQLITE_AFF_INTEGER || aff==SQLITE_AFF_NUMERIC; - } - case TK_FLOAT: { - return aff==SQLITE_AFF_REAL || aff==SQLITE_AFF_NUMERIC; - } - case TK_STRING: { - return aff==SQLITE_AFF_TEXT; - } - case TK_BLOB: { - return 1; - } - case TK_COLUMN: { - assert( p->iTable>=0 ); /* p cannot be part of a CHECK constraint */ - return p->iColumn<0 - && (aff==SQLITE_AFF_INTEGER || aff==SQLITE_AFF_NUMERIC); - } - default: { - return 0; - } - } -} - -/* -** Return TRUE if the given string is a row-id column name. -*/ -int sqlite3IsRowid(const char *z){ - if( sqlite3StrICmp(z, "_ROWID_")==0 ) return 1; - if( sqlite3StrICmp(z, "ROWID")==0 ) return 1; - if( sqlite3StrICmp(z, "OID")==0 ) return 1; - return 0; -} - -/* -** pX is the RHS of an IN operator. If pX is a SELECT statement -** that can be simplified to a direct table access, then return -** a pointer to the SELECT statement. If pX is not a SELECT statement, -** or if the SELECT statement needs to be manifested into a transient -** table, then return NULL. -*/ -#ifndef SQLITE_OMIT_SUBQUERY -static Select *isCandidateForInOpt(Expr *pX){ - Select *p; - SrcList *pSrc; - ExprList *pEList; - Table *pTab; - int i; - if( !ExprHasProperty(pX, EP_xIsSelect) ) return 0; /* Not a subquery */ - if( ExprHasProperty(pX, EP_VarSelect) ) return 0; /* Correlated subq */ - p = pX->x.pSelect; - if( p->pPrior ) return 0; /* Not a compound SELECT */ - if( p->selFlags & (SF_Distinct|SF_Aggregate) ){ - testcase( (p->selFlags & (SF_Distinct|SF_Aggregate))==SF_Distinct ); - testcase( (p->selFlags & (SF_Distinct|SF_Aggregate))==SF_Aggregate ); - return 0; /* No DISTINCT keyword and no aggregate functions */ - } - assert( p->pGroupBy==0 ); /* Has no GROUP BY clause */ - if( p->pLimit ) return 0; /* Has no LIMIT clause */ - if( p->pWhere ) return 0; /* Has no WHERE clause */ - pSrc = p->pSrc; - assert( pSrc!=0 ); - if( pSrc->nSrc!=1 ) return 0; /* Single term in FROM clause */ - if( pSrc->a[0].pSelect ) return 0; /* FROM is not a subquery or view */ - pTab = pSrc->a[0].pTab; - assert( pTab!=0 ); - assert( pTab->pSelect==0 ); /* FROM clause is not a view */ - if( IsVirtual(pTab) ) return 0; /* FROM clause not a virtual table */ - pEList = p->pEList; - assert( pEList!=0 ); - /* All SELECT results must be columns. */ - for(i=0; i<pEList->nExpr; i++){ - Expr *pRes = pEList->a[i].pExpr; - if( pRes->op!=TK_COLUMN ) return 0; - assert( pRes->iTable==pSrc->a[0].iCursor ); /* Not a correlated subquery */ - } - return p; -} -#endif /* SQLITE_OMIT_SUBQUERY */ - -#ifndef SQLITE_OMIT_SUBQUERY -/* -** Generate code that checks the left-most column of index table iCur to see if -** it contains any NULL entries. Cause the register at regHasNull to be set -** to a non-NULL value if iCur contains no NULLs. Cause register regHasNull -** to be set to NULL if iCur contains one or more NULL values. -*/ -static void sqlite3SetHasNullFlag(Vdbe *v, int iCur, int regHasNull){ - int addr1; - sqlite3VdbeAddOp2(v, OP_Integer, 0, regHasNull); - addr1 = sqlite3VdbeAddOp1(v, OP_Rewind, iCur); VdbeCoverage(v); - sqlite3VdbeAddOp3(v, OP_Column, iCur, 0, regHasNull); - sqlite3VdbeChangeP5(v, OPFLAG_TYPEOFARG); - VdbeComment((v, "first_entry_in(%d)", iCur)); - sqlite3VdbeJumpHere(v, addr1); -} -#endif - - -#ifndef SQLITE_OMIT_SUBQUERY -/* -** The argument is an IN operator with a list (not a subquery) on the -** right-hand side. Return TRUE if that list is constant. -*/ -static int sqlite3InRhsIsConstant(Expr *pIn){ - Expr *pLHS; - int res; - assert( !ExprHasProperty(pIn, EP_xIsSelect) ); - pLHS = pIn->pLeft; - pIn->pLeft = 0; - res = sqlite3ExprIsConstant(pIn); - pIn->pLeft = pLHS; - return res; -} -#endif - -/* -** This function is used by the implementation of the IN (...) operator. -** The pX parameter is the expression on the RHS of the IN operator, which -** might be either a list of expressions or a subquery. -** -** The job of this routine is to find or create a b-tree object that can -** be used either to test for membership in the RHS set or to iterate through -** all members of the RHS set, skipping duplicates. -** -** A cursor is opened on the b-tree object that is the RHS of the IN operator -** and pX->iTable is set to the index of that cursor. -** -** The returned value of this function indicates the b-tree type, as follows: -** -** IN_INDEX_ROWID - The cursor was opened on a database table. -** IN_INDEX_INDEX_ASC - The cursor was opened on an ascending index. -** IN_INDEX_INDEX_DESC - The cursor was opened on a descending index. -** IN_INDEX_EPH - The cursor was opened on a specially created and -** populated epheremal table. -** IN_INDEX_NOOP - No cursor was allocated. The IN operator must be -** implemented as a sequence of comparisons. -** -** An existing b-tree might be used if the RHS expression pX is a simple -** subquery such as: -** -** SELECT <column1>, <column2>... FROM <table> -** -** If the RHS of the IN operator is a list or a more complex subquery, then -** an ephemeral table might need to be generated from the RHS and then -** pX->iTable made to point to the ephemeral table instead of an -** existing table. -** -** The inFlags parameter must contain, at a minimum, one of the bits -** IN_INDEX_MEMBERSHIP or IN_INDEX_LOOP but not both. If inFlags contains -** IN_INDEX_MEMBERSHIP, then the generated table will be used for a fast -** membership test. When the IN_INDEX_LOOP bit is set, the IN index will -** be used to loop over all values of the RHS of the IN operator. -** -** When IN_INDEX_LOOP is used (and the b-tree will be used to iterate -** through the set members) then the b-tree must not contain duplicates. -** An epheremal table will be created unless the selected columns are guaranteed -** to be unique - either because it is an INTEGER PRIMARY KEY or due to -** a UNIQUE constraint or index. -** -** When IN_INDEX_MEMBERSHIP is used (and the b-tree will be used -** for fast set membership tests) then an epheremal table must -** be used unless <columns> is a single INTEGER PRIMARY KEY column or an -** index can be found with the specified <columns> as its left-most. -** -** If the IN_INDEX_NOOP_OK and IN_INDEX_MEMBERSHIP are both set and -** if the RHS of the IN operator is a list (not a subquery) then this -** routine might decide that creating an ephemeral b-tree for membership -** testing is too expensive and return IN_INDEX_NOOP. In that case, the -** calling routine should implement the IN operator using a sequence -** of Eq or Ne comparison operations. -** -** 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 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 *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 *prRhsHasNull, then -** the value in that register will be NULL if the b-tree contains one or more -** NULL values, and it will be some non-NULL value if the b-tree contains no -** NULL values. -** -** If the aiMap parameter is not NULL, it must point to an array containing -** one element for each column returned by the SELECT statement on the RHS -** of the IN(...) operator. The i'th entry of the array is populated with the -** offset of the index column that matches the i'th column returned by the -** SELECT. For example, if the expression and selected index are: -** -** (?,?,?) IN (SELECT a, b, c FROM t1) -** CREATE INDEX i1 ON t1(b, c, a); -** -** then aiMap[] is populated with {2, 0, 1}. -*/ -#ifndef SQLITE_OMIT_SUBQUERY -int sqlite3FindInIndex( - Parse *pParse, /* Parsing context */ - Expr *pX, /* The right-hand side (RHS) of the IN operator */ - u32 inFlags, /* IN_INDEX_LOOP, _MEMBERSHIP, and/or _NOOP_OK */ - int *prRhsHasNull, /* Register holding NULL status. See notes */ - int *aiMap /* Mapping from Index fields to RHS fields */ -){ - 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 */ - int mustBeUnique; /* True if RHS must be unique */ - Vdbe *v = sqlite3GetVdbe(pParse); /* Virtual machine being coded */ - - assert( pX->op==TK_IN ); - mustBeUnique = (inFlags & IN_INDEX_LOOP)!=0; - - /* If the RHS of this IN(...) operator is a SELECT, and if it matters - ** whether or not the SELECT result contains NULL values, check whether - ** or not NULL is actually possible (it may not be, for example, due - ** to NOT NULL constraints in the schema). If no NULL values are possible, - ** set prRhsHasNull to 0 before continuing. */ - if( prRhsHasNull && (pX->flags & EP_xIsSelect) ){ - int i; - ExprList *pEList = pX->x.pSelect->pEList; - for(i=0; i<pEList->nExpr; i++){ - if( sqlite3ExprCanBeNull(pEList->a[i].pExpr) ) break; - } - if( i==pEList->nExpr ){ - prRhsHasNull = 0; - } - } - - /* Check to see if an existing table or index can be used to - ** satisfy the query. This is preferable to generating a new - ** ephemeral table. */ - if( pParse->nErr==0 && (p = isCandidateForInOpt(pX))!=0 ){ - sqlite3 *db = pParse->db; /* Database connection */ - Table *pTab; /* Table <table>. */ - i16 iDb; /* Database idx for pTab */ - ExprList *pEList = p->pEList; - int nExpr = pEList->nExpr; - - assert( p->pEList!=0 ); /* Because of isCandidateForInOpt(p) */ - assert( p->pEList->a[0].pExpr!=0 ); /* Because of isCandidateForInOpt(p) */ - assert( p->pSrc!=0 ); /* Because of isCandidateForInOpt(p) */ - pTab = p->pSrc->a[0].pTab; - - /* Code an OP_Transaction and OP_TableLock for <table>. */ - iDb = sqlite3SchemaToIndex(db, pTab->pSchema); - sqlite3CodeVerifySchema(pParse, iDb); - sqlite3TableLock(pParse, iDb, pTab->tnum, 0, pTab->zName); - - assert(v); /* sqlite3GetVdbe() has always been previously called */ - if( nExpr==1 && pEList->a[0].pExpr->iColumn<0 ){ - /* The "x IN (SELECT rowid FROM table)" case */ - int iAddr = sqlite3VdbeAddOp0(v, OP_Once); - VdbeCoverage(v); - - sqlite3OpenTable(pParse, iTab, iDb, pTab, OP_OpenRead); - eType = IN_INDEX_ROWID; - - sqlite3VdbeJumpHere(v, iAddr); - }else{ - Index *pIdx; /* Iterator variable */ - int affinity_ok = 1; - int i; - - /* Check that the affinity that will be used to perform each - ** comparison is the same as the affinity of each column in table - ** on the RHS of the IN operator. If it not, it is not possible to - ** use any index of the RHS table. */ - for(i=0; i<nExpr && affinity_ok; i++){ - Expr *pLhs = sqlite3VectorFieldSubexpr(pX->pLeft, i); - int iCol = pEList->a[i].pExpr->iColumn; - char idxaff = sqlite3TableColumnAffinity(pTab,iCol); /* RHS table */ - char cmpaff = sqlite3CompareAffinity(pLhs, idxaff); - testcase( cmpaff==SQLITE_AFF_BLOB ); - testcase( cmpaff==SQLITE_AFF_TEXT ); - switch( cmpaff ){ - case SQLITE_AFF_BLOB: - break; - case SQLITE_AFF_TEXT: - /* sqlite3CompareAffinity() only returns TEXT if one side or the - ** other has no affinity and the other side is TEXT. Hence, - ** the only way for cmpaff to be TEXT is for idxaff to be TEXT - ** and for the term on the LHS of the IN to have no affinity. */ - assert( idxaff==SQLITE_AFF_TEXT ); - break; - default: - affinity_ok = sqlite3IsNumericAffinity(idxaff); - } - } - - if( affinity_ok ){ - /* Search for an existing index that will work for this IN operator */ - for(pIdx=pTab->pIndex; pIdx && eType==0; pIdx=pIdx->pNext){ - Bitmask colUsed; /* Columns of the index used */ - Bitmask mCol; /* Mask for the current column */ - if( pIdx->nColumn<nExpr ) continue; - /* Maximum nColumn is BMS-2, not BMS-1, so that we can compute - ** BITMASK(nExpr) without overflowing */ - testcase( pIdx->nColumn==BMS-2 ); - testcase( pIdx->nColumn==BMS-1 ); - if( pIdx->nColumn>=BMS-1 ) continue; - if( mustBeUnique ){ - if( pIdx->nKeyCol>nExpr - ||(pIdx->nColumn>nExpr && !IsUniqueIndex(pIdx)) - ){ - continue; /* This index is not unique over the IN RHS columns */ - } - } - - colUsed = 0; /* Columns of index used so far */ - for(i=0; i<nExpr; i++){ - Expr *pLhs = sqlite3VectorFieldSubexpr(pX->pLeft, i); - Expr *pRhs = pEList->a[i].pExpr; - CollSeq *pReq = sqlite3BinaryCompareCollSeq(pParse, pLhs, pRhs); - int j; - - assert( pReq!=0 || pRhs->iColumn==XN_ROWID || pParse->nErr ); - for(j=0; j<nExpr; j++){ - if( pIdx->aiColumn[j]!=pRhs->iColumn ) continue; - assert( pIdx->azColl[j] ); - if( pReq!=0 && sqlite3StrICmp(pReq->zName, pIdx->azColl[j])!=0 ){ - continue; - } - break; - } - if( j==nExpr ) break; - mCol = MASKBIT(j); - if( mCol & colUsed ) break; /* Each column used only once */ - colUsed |= mCol; - if( aiMap ) aiMap[i] = j; - } - - assert( i==nExpr || colUsed!=(MASKBIT(nExpr)-1) ); - if( colUsed==(MASKBIT(nExpr)-1) ){ - /* If we reach this point, that means the index pIdx is usable */ - int iAddr = sqlite3VdbeAddOp0(v, OP_Once); VdbeCoverage(v); - ExplainQueryPlan((pParse, 0, - "USING INDEX %s FOR IN-OPERATOR",pIdx->zName)); - sqlite3VdbeAddOp3(v, OP_OpenRead, iTab, pIdx->tnum, iDb); - sqlite3VdbeSetP4KeyInfo(pParse, pIdx); - VdbeComment((v, "%s", pIdx->zName)); - assert( IN_INDEX_INDEX_DESC == IN_INDEX_INDEX_ASC+1 ); - eType = IN_INDEX_INDEX_ASC + pIdx->aSortOrder[0]; - - if( prRhsHasNull ){ -#ifdef SQLITE_ENABLE_COLUMN_USED_MASK - i64 mask = (1<<nExpr)-1; - sqlite3VdbeAddOp4Dup8(v, OP_ColumnsUsed, - iTab, 0, 0, (u8*)&mask, P4_INT64); -#endif - *prRhsHasNull = ++pParse->nMem; - if( nExpr==1 ){ - sqlite3SetHasNullFlag(v, iTab, *prRhsHasNull); - } - } - sqlite3VdbeJumpHere(v, iAddr); - } - } /* End loop over indexes */ - } /* End if( affinity_ok ) */ - } /* End if not an rowid index */ - } /* End attempt to optimize using an index */ - - /* If no preexisting index is available for the IN clause - ** and IN_INDEX_NOOP is an allowed reply - ** and the RHS of the IN operator is a list, not a subquery - ** and the RHS is not constant or has two or fewer terms, - ** then it is not worth creating an ephemeral table to evaluate - ** the IN operator so return IN_INDEX_NOOP. - */ - if( eType==0 - && (inFlags & IN_INDEX_NOOP_OK) - && !ExprHasProperty(pX, EP_xIsSelect) - && (!sqlite3InRhsIsConstant(pX) || pX->x.pList->nExpr<=2) - ){ - eType = IN_INDEX_NOOP; - } - - if( eType==0 ){ - /* Could not find an existing table or index to use as the RHS b-tree. - ** We will have to generate an ephemeral table to do the job. - */ - u32 savedNQueryLoop = pParse->nQueryLoop; - int rMayHaveNull = 0; - eType = IN_INDEX_EPH; - if( inFlags & IN_INDEX_LOOP ){ - pParse->nQueryLoop = 0; - if( pX->pLeft->iColumn<0 && !ExprHasProperty(pX, EP_xIsSelect) ){ - eType = IN_INDEX_ROWID; - } - }else if( prRhsHasNull ){ - *prRhsHasNull = rMayHaveNull = ++pParse->nMem; - } - sqlite3CodeSubselect(pParse, pX, rMayHaveNull, eType==IN_INDEX_ROWID); - pParse->nQueryLoop = savedNQueryLoop; - }else{ - pX->iTable = iTab; - } - - if( aiMap && eType!=IN_INDEX_INDEX_ASC && eType!=IN_INDEX_INDEX_DESC ){ - int i, n; - n = sqlite3ExprVectorSize(pX->pLeft); - for(i=0; i<n; i++) aiMap[i] = i; - } - return eType; -} -#endif - -#ifndef SQLITE_OMIT_SUBQUERY -/* -** Argument pExpr is an (?, ?...) IN(...) expression. This -** function allocates and returns a nul-terminated string containing -** the affinities to be used for each column of the comparison. -** -** It is the responsibility of the caller to ensure that the returned -** string is eventually freed using sqlite3DbFree(). -*/ -static char *exprINAffinity(Parse *pParse, Expr *pExpr){ - Expr *pLeft = pExpr->pLeft; - int nVal = sqlite3ExprVectorSize(pLeft); - Select *pSelect = (pExpr->flags & EP_xIsSelect) ? pExpr->x.pSelect : 0; - char *zRet; - - assert( pExpr->op==TK_IN ); - zRet = sqlite3DbMallocRaw(pParse->db, nVal+1); - if( zRet ){ - int i; - for(i=0; i<nVal; i++){ - Expr *pA = sqlite3VectorFieldSubexpr(pLeft, i); - char a = sqlite3ExprAffinity(pA); - if( pSelect ){ - zRet[i] = sqlite3CompareAffinity(pSelect->pEList->a[i].pExpr, a); - }else{ - zRet[i] = a; - } - } - zRet[nVal] = '\0'; - } - return zRet; -} -#endif - -#ifndef SQLITE_OMIT_SUBQUERY -/* -** Load the Parse object passed as the first argument with an error -** message of the form: -** -** "sub-select returns N columns - expected M" -*/ -void sqlite3SubselectError(Parse *pParse, int nActual, int nExpect){ - const char *zFmt = "sub-select returns %d columns - expected %d"; - sqlite3ErrorMsg(pParse, zFmt, nActual, nExpect); -} -#endif - -/* -** Expression pExpr is a vector that has been used in a context where -** it is not permitted. If pExpr is a sub-select vector, this routine -** loads the Parse object with a message of the form: -** -** "sub-select returns N columns - expected 1" -** -** Or, if it is a regular scalar vector: -** -** "row value misused" -*/ -void sqlite3VectorErrorMsg(Parse *pParse, Expr *pExpr){ -#ifndef SQLITE_OMIT_SUBQUERY - if( pExpr->flags & EP_xIsSelect ){ - sqlite3SubselectError(pParse, pExpr->x.pSelect->pEList->nExpr, 1); - }else -#endif - { - sqlite3ErrorMsg(pParse, "row value misused"); - } -} - -/* -** Generate code for scalar subqueries used as a subquery expression, EXISTS, -** or IN operators. Examples: -** -** (SELECT a FROM b) -- subquery -** EXISTS (SELECT a FROM b) -- EXISTS subquery -** x IN (4,5,11) -- IN operator with list on right-hand side -** x IN (SELECT a FROM b) -- IN operator with subquery on the right -** -** The pExpr parameter describes the expression that contains the IN -** operator or subquery. -** -** If parameter isRowid is non-zero, then expression pExpr is guaranteed -** to be of the form "<rowid> IN (?, ?, ?)", where <rowid> is a reference -** to some integer key column of a table B-Tree. In this case, use an -** intkey B-Tree to store the set of IN(...) values instead of the usual -** (slower) variable length keys B-Tree. -** -** If rMayHaveNull is non-zero, that means that the operation is an IN -** (not a SELECT or EXISTS) and that the RHS might contains NULLs. -** All this routine does is initialize the register given by rMayHaveNull -** to NULL. Calling routines will take care of changing this register -** value to non-NULL if the RHS is NULL-free. -** -** For a SELECT or EXISTS operator, return the register that holds the -** result. For a multi-column SELECT, the result is stored in a contiguous -** array of registers and the return value is the register of the left-most -** result column. Return 0 for IN operators or if an error occurs. -*/ -#ifndef SQLITE_OMIT_SUBQUERY -int sqlite3CodeSubselect( - Parse *pParse, /* Parsing context */ - Expr *pExpr, /* The IN, SELECT, or EXISTS operator */ - int rHasNullFlag, /* Register that records whether NULLs exist in RHS */ - int isRowid /* If true, LHS of IN operator is a rowid */ -){ - int jmpIfDynamic = -1; /* One-time test address */ - int rReg = 0; /* Register storing resulting */ - Vdbe *v = sqlite3GetVdbe(pParse); - if( NEVER(v==0) ) return 0; - sqlite3ExprCachePush(pParse); - - /* The evaluation of the IN/EXISTS/SELECT must be repeated every time it - ** is encountered if any of the following is true: - ** - ** * The right-hand side is a correlated subquery - ** * The right-hand side is an expression list containing variables - ** * We are inside a trigger - ** - ** If all of the above are false, then we can run this code just once - ** save the results, and reuse the same result on subsequent invocations. - */ - if( !ExprHasProperty(pExpr, EP_VarSelect) ){ - jmpIfDynamic = sqlite3VdbeAddOp0(v, OP_Once); VdbeCoverage(v); - } - - switch( pExpr->op ){ - case TK_IN: { - int addr; /* Address of OP_OpenEphemeral instruction */ - Expr *pLeft = pExpr->pLeft; /* the LHS of the IN operator */ - KeyInfo *pKeyInfo = 0; /* Key information */ - int nVal; /* Size of vector pLeft */ - - nVal = sqlite3ExprVectorSize(pLeft); - assert( !isRowid || nVal==1 ); - - /* Whether this is an 'x IN(SELECT...)' or an 'x IN(<exprlist>)' - ** expression it is handled the same way. An ephemeral table is - ** filled with index keys representing the results from the - ** SELECT or the <exprlist>. - ** - ** If the 'x' expression is a column value, or the SELECT... - ** statement returns a column value, then the affinity of that - ** column is used to build the index keys. If both 'x' and the - ** SELECT... statement are columns, then numeric affinity is used - ** if either column has NUMERIC or INTEGER affinity. If neither - ** 'x' nor the SELECT... statement are columns, then numeric affinity - ** is used. - */ - pExpr->iTable = pParse->nTab++; - addr = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, - pExpr->iTable, (isRowid?0:nVal)); - pKeyInfo = isRowid ? 0 : sqlite3KeyInfoAlloc(pParse->db, nVal, 1); - - if( ExprHasProperty(pExpr, EP_xIsSelect) ){ - /* Case 1: expr IN (SELECT ...) - ** - ** Generate code to write the results of the select into the temporary - ** table allocated and opened above. - */ - Select *pSelect = pExpr->x.pSelect; - ExprList *pEList = pSelect->pEList; - - ExplainQueryPlan((pParse, 1, "%sLIST SUBQUERY", - jmpIfDynamic>=0?"":"CORRELATED " - )); - assert( !isRowid ); - /* If the LHS and RHS of the IN operator do not match, that - ** error will have been caught long before we reach this point. */ - if( ALWAYS(pEList->nExpr==nVal) ){ - SelectDest dest; - int i; - sqlite3SelectDestInit(&dest, SRT_Set, pExpr->iTable); - dest.zAffSdst = exprINAffinity(pParse, pExpr); - pSelect->iLimit = 0; - testcase( pSelect->selFlags & SF_Distinct ); - testcase( pKeyInfo==0 ); /* Caused by OOM in sqlite3KeyInfoAlloc() */ - if( sqlite3Select(pParse, pSelect, &dest) ){ - sqlite3DbFree(pParse->db, dest.zAffSdst); - sqlite3KeyInfoUnref(pKeyInfo); - return 0; - } - sqlite3DbFree(pParse->db, dest.zAffSdst); - assert( pKeyInfo!=0 ); /* OOM will cause exit after sqlite3Select() */ - assert( pEList!=0 ); - assert( pEList->nExpr>0 ); - assert( sqlite3KeyInfoIsWriteable(pKeyInfo) ); - for(i=0; i<nVal; i++){ - Expr *p = sqlite3VectorFieldSubexpr(pLeft, i); - pKeyInfo->aColl[i] = sqlite3BinaryCompareCollSeq( - pParse, p, pEList->a[i].pExpr - ); - } - } - }else if( ALWAYS(pExpr->x.pList!=0) ){ - /* Case 2: expr IN (exprlist) - ** - ** For each expression, build an index key from the evaluation and - ** store it in the temporary table. If <expr> is a column, then use - ** that columns affinity when building index keys. If <expr> is not - ** a column, use numeric affinity. - */ - char affinity; /* Affinity of the LHS of the IN */ - int i; - ExprList *pList = pExpr->x.pList; - struct ExprList_item *pItem; - int r1, r2, r3; - affinity = sqlite3ExprAffinity(pLeft); - if( !affinity ){ - affinity = SQLITE_AFF_BLOB; - } - if( pKeyInfo ){ - assert( sqlite3KeyInfoIsWriteable(pKeyInfo) ); - pKeyInfo->aColl[0] = sqlite3ExprCollSeq(pParse, pExpr->pLeft); - } - - /* Loop through each expression in <exprlist>. */ - r1 = sqlite3GetTempReg(pParse); - r2 = sqlite3GetTempReg(pParse); - if( isRowid ) sqlite3VdbeAddOp4(v, OP_Blob, 0, r2, 0, "", P4_STATIC); - for(i=pList->nExpr, pItem=pList->a; i>0; i--, pItem++){ - Expr *pE2 = pItem->pExpr; - int iValToIns; - - /* If the expression is not constant then we will need to - ** disable the test that was generated above that makes sure - ** this code only executes once. Because for a non-constant - ** expression we need to rerun this code each time. - */ - if( jmpIfDynamic>=0 && !sqlite3ExprIsConstant(pE2) ){ - sqlite3VdbeChangeToNoop(v, jmpIfDynamic); - jmpIfDynamic = -1; - } - - /* Evaluate the expression and insert it into the temp table */ - if( isRowid && sqlite3ExprIsInteger(pE2, &iValToIns) ){ - sqlite3VdbeAddOp3(v, OP_InsertInt, pExpr->iTable, r2, iValToIns); - }else{ - r3 = sqlite3ExprCodeTarget(pParse, pE2, r1); - if( isRowid ){ - sqlite3VdbeAddOp2(v, OP_MustBeInt, r3, - sqlite3VdbeCurrentAddr(v)+2); - VdbeCoverage(v); - sqlite3VdbeAddOp3(v, OP_Insert, pExpr->iTable, r2, r3); - }else{ - sqlite3VdbeAddOp4(v, OP_MakeRecord, r3, 1, r2, &affinity, 1); - sqlite3ExprCacheAffinityChange(pParse, r3, 1); - sqlite3VdbeAddOp4Int(v, OP_IdxInsert, pExpr->iTable, r2, r3, 1); - } - } - } - sqlite3ReleaseTempReg(pParse, r1); - sqlite3ReleaseTempReg(pParse, r2); - } - if( pKeyInfo ){ - sqlite3VdbeChangeP4(v, addr, (void *)pKeyInfo, P4_KEYINFO); - } - break; - } - - case TK_EXISTS: - case TK_SELECT: - default: { - /* Case 3: (SELECT ... FROM ...) - ** or: EXISTS(SELECT ... FROM ...) - ** - ** For a SELECT, generate code to put the values for all columns of - ** the first row into an array of registers and return the index of - ** the first register. - ** - ** If this is an EXISTS, write an integer 0 (not exists) or 1 (exists) - ** into a register and return that register number. - ** - ** In both cases, the query is augmented with "LIMIT 1". Any - ** preexisting limit is discarded in place of the new LIMIT 1. - */ - Select *pSel; /* SELECT statement to encode */ - SelectDest dest; /* How to deal with SELECT result */ - int nReg; /* Registers to allocate */ - Expr *pLimit; /* New limit expression */ - - testcase( pExpr->op==TK_EXISTS ); - testcase( pExpr->op==TK_SELECT ); - assert( pExpr->op==TK_EXISTS || pExpr->op==TK_SELECT ); - assert( ExprHasProperty(pExpr, EP_xIsSelect) ); - - pSel = pExpr->x.pSelect; - ExplainQueryPlan((pParse, 1, "%sSCALAR SUBQUERY", - jmpIfDynamic>=0?"":"CORRELATED ")); - nReg = pExpr->op==TK_SELECT ? pSel->pEList->nExpr : 1; - sqlite3SelectDestInit(&dest, 0, pParse->nMem+1); - pParse->nMem += nReg; - if( pExpr->op==TK_SELECT ){ - dest.eDest = SRT_Mem; - dest.iSdst = dest.iSDParm; - dest.nSdst = nReg; - sqlite3VdbeAddOp3(v, OP_Null, 0, dest.iSDParm, dest.iSDParm+nReg-1); - VdbeComment((v, "Init subquery result")); - }else{ - dest.eDest = SRT_Exists; - sqlite3VdbeAddOp2(v, OP_Integer, 0, dest.iSDParm); - VdbeComment((v, "Init EXISTS result")); - } - pLimit = sqlite3ExprAlloc(pParse->db, TK_INTEGER,&sqlite3IntTokens[1], 0); - if( pSel->pLimit ){ - sqlite3ExprDelete(pParse->db, pSel->pLimit->pLeft); - pSel->pLimit->pLeft = pLimit; - }else{ - pSel->pLimit = sqlite3PExpr(pParse, TK_LIMIT, pLimit, 0); - } - pSel->iLimit = 0; - if( sqlite3Select(pParse, pSel, &dest) ){ - return 0; - } - rReg = dest.iSDParm; - ExprSetVVAProperty(pExpr, EP_NoReduce); - break; - } - } - - if( rHasNullFlag ){ - sqlite3SetHasNullFlag(v, pExpr->iTable, rHasNullFlag); - } - - if( jmpIfDynamic>=0 ){ - sqlite3VdbeJumpHere(v, jmpIfDynamic); - } - sqlite3ExprCachePop(pParse); - - return rReg; -} -#endif /* SQLITE_OMIT_SUBQUERY */ - -#ifndef SQLITE_OMIT_SUBQUERY -/* -** Expr pIn is an IN(...) expression. This function checks that the -** sub-select on the RHS of the IN() operator has the same number of -** columns as the vector on the LHS. Or, if the RHS of the IN() is not -** a sub-query, that the LHS is a vector of size 1. -*/ -int sqlite3ExprCheckIN(Parse *pParse, Expr *pIn){ - int nVector = sqlite3ExprVectorSize(pIn->pLeft); - if( (pIn->flags & EP_xIsSelect) ){ - if( nVector!=pIn->x.pSelect->pEList->nExpr ){ - sqlite3SubselectError(pParse, pIn->x.pSelect->pEList->nExpr, nVector); - return 1; - } - }else if( nVector!=1 ){ - sqlite3VectorErrorMsg(pParse, pIn->pLeft); - return 1; - } - return 0; -} -#endif - -#ifndef SQLITE_OMIT_SUBQUERY -/* -** Generate code for an IN expression. -** -** x IN (SELECT ...) -** x IN (value, value, ...) -** -** The left-hand side (LHS) is a scalar or vector expression. The -** right-hand side (RHS) is an array of zero or more scalar values, or a -** subquery. If the RHS is a subquery, the number of result columns must -** match the number of columns in the vector on the LHS. If the RHS is -** a list of values, the LHS must be a scalar. -** -** The IN operator is true if the LHS value is contained within the RHS. -** The result is false if the LHS is definitely not in the RHS. The -** result is NULL if the presence of the LHS in the RHS cannot be -** determined due to NULLs. -** -** This routine generates code that jumps to destIfFalse if the LHS is not -** contained within the RHS. If due to NULLs we cannot determine if the LHS -** is contained in the RHS then jump to destIfNull. If the LHS is contained -** within the RHS then fall through. -** -** See the separate in-operator.md documentation file in the canonical -** SQLite source tree for additional information. -*/ -static void sqlite3ExprCodeIN( - Parse *pParse, /* Parsing and code generating context */ - Expr *pExpr, /* The IN expression */ - int destIfFalse, /* Jump here if LHS is not contained in the RHS */ - int destIfNull /* Jump here if the results are unknown due to NULLs */ -){ - int rRhsHasNull = 0; /* Register that is true if RHS contains NULL values */ - int eType; /* Type of the RHS */ - int rLhs; /* Register(s) holding the LHS values */ - int rLhsOrig; /* LHS values prior to reordering by aiMap[] */ - Vdbe *v; /* Statement under construction */ - int *aiMap = 0; /* Map from vector field to index column */ - char *zAff = 0; /* Affinity string for comparisons */ - int nVector; /* Size of vectors for this IN operator */ - int iDummy; /* Dummy parameter to exprCodeVector() */ - Expr *pLeft; /* The LHS of the IN operator */ - int i; /* loop counter */ - int destStep2; /* Where to jump when NULLs seen in step 2 */ - int destStep6 = 0; /* Start of code for Step 6 */ - int addrTruthOp; /* Address of opcode that determines the IN is true */ - int destNotNull; /* Jump here if a comparison is not true in step 6 */ - int addrTop; /* Top of the step-6 loop */ - - pLeft = pExpr->pLeft; - if( sqlite3ExprCheckIN(pParse, pExpr) ) return; - zAff = exprINAffinity(pParse, pExpr); - nVector = sqlite3ExprVectorSize(pExpr->pLeft); - aiMap = (int*)sqlite3DbMallocZero( - pParse->db, nVector*(sizeof(int) + sizeof(char)) + 1 - ); - if( pParse->db->mallocFailed ) goto sqlite3ExprCodeIN_oom_error; - - /* Attempt to compute the RHS. After this step, if anything other than - ** IN_INDEX_NOOP is returned, the table opened ith cursor pExpr->iTable - ** contains the values that make up the RHS. If IN_INDEX_NOOP is returned, - ** the RHS has not yet been coded. */ - v = pParse->pVdbe; - assert( v!=0 ); /* OOM detected prior to this routine */ - VdbeNoopComment((v, "begin IN expr")); - eType = sqlite3FindInIndex(pParse, pExpr, - IN_INDEX_MEMBERSHIP | IN_INDEX_NOOP_OK, - destIfFalse==destIfNull ? 0 : &rRhsHasNull, aiMap); - - assert( pParse->nErr || nVector==1 || eType==IN_INDEX_EPH - || eType==IN_INDEX_INDEX_ASC || eType==IN_INDEX_INDEX_DESC - ); -#ifdef SQLITE_DEBUG - /* Confirm that aiMap[] contains nVector integer values between 0 and - ** nVector-1. */ - for(i=0; i<nVector; i++){ - int j, cnt; - for(cnt=j=0; j<nVector; j++) if( aiMap[j]==i ) cnt++; - assert( cnt==1 ); - } -#endif - - /* Code the LHS, the <expr> from "<expr> IN (...)". If the LHS is a - ** vector, then it is stored in an array of nVector registers starting - ** at r1. - ** - ** sqlite3FindInIndex() might have reordered the fields of the LHS vector - ** so that the fields are in the same order as an existing index. The - ** aiMap[] array contains a mapping from the original LHS field order to - ** the field order that matches the RHS index. - */ - sqlite3ExprCachePush(pParse); - rLhsOrig = exprCodeVector(pParse, pLeft, &iDummy); - for(i=0; i<nVector && aiMap[i]==i; i++){} /* Are LHS fields reordered? */ - if( i==nVector ){ - /* LHS fields are not reordered */ - rLhs = rLhsOrig; - }else{ - /* Need to reorder the LHS fields according to aiMap */ - rLhs = sqlite3GetTempRange(pParse, nVector); - for(i=0; i<nVector; i++){ - sqlite3VdbeAddOp3(v, OP_Copy, rLhsOrig+i, rLhs+aiMap[i], 0); - } - } - - /* If sqlite3FindInIndex() did not find or create an index that is - ** suitable for evaluating the IN operator, then evaluate using a - ** sequence of comparisons. - ** - ** This is step (1) in the in-operator.md optimized algorithm. - */ - if( eType==IN_INDEX_NOOP ){ - ExprList *pList = pExpr->x.pList; - CollSeq *pColl = sqlite3ExprCollSeq(pParse, pExpr->pLeft); - int labelOk = sqlite3VdbeMakeLabel(v); - int r2, regToFree; - int regCkNull = 0; - int ii; - assert( !ExprHasProperty(pExpr, EP_xIsSelect) ); - if( destIfNull!=destIfFalse ){ - regCkNull = sqlite3GetTempReg(pParse); - sqlite3VdbeAddOp3(v, OP_BitAnd, rLhs, rLhs, regCkNull); - } - for(ii=0; ii<pList->nExpr; ii++){ - r2 = sqlite3ExprCodeTemp(pParse, pList->a[ii].pExpr, ®ToFree); - if( regCkNull && sqlite3ExprCanBeNull(pList->a[ii].pExpr) ){ - sqlite3VdbeAddOp3(v, OP_BitAnd, regCkNull, r2, regCkNull); - } - if( ii<pList->nExpr-1 || destIfNull!=destIfFalse ){ - sqlite3VdbeAddOp4(v, OP_Eq, rLhs, labelOk, r2, - (void*)pColl, P4_COLLSEQ); - VdbeCoverageIf(v, ii<pList->nExpr-1); - VdbeCoverageIf(v, ii==pList->nExpr-1); - sqlite3VdbeChangeP5(v, zAff[0]); - }else{ - assert( destIfNull==destIfFalse ); - sqlite3VdbeAddOp4(v, OP_Ne, rLhs, destIfFalse, r2, - (void*)pColl, P4_COLLSEQ); VdbeCoverage(v); - sqlite3VdbeChangeP5(v, zAff[0] | SQLITE_JUMPIFNULL); - } - sqlite3ReleaseTempReg(pParse, regToFree); - } - if( regCkNull ){ - sqlite3VdbeAddOp2(v, OP_IsNull, regCkNull, destIfNull); VdbeCoverage(v); - sqlite3VdbeGoto(v, destIfFalse); - } - sqlite3VdbeResolveLabel(v, labelOk); - sqlite3ReleaseTempReg(pParse, regCkNull); - goto sqlite3ExprCodeIN_finished; - } - - /* Step 2: Check to see if the LHS contains any NULL columns. If the - ** LHS does contain NULLs then the result must be either FALSE or NULL. - ** We will then skip the binary search of the RHS. - */ - if( destIfNull==destIfFalse ){ - destStep2 = destIfFalse; - }else{ - destStep2 = destStep6 = sqlite3VdbeMakeLabel(v); - } - for(i=0; i<nVector; i++){ - Expr *p = sqlite3VectorFieldSubexpr(pExpr->pLeft, i); - if( sqlite3ExprCanBeNull(p) ){ - sqlite3VdbeAddOp2(v, OP_IsNull, rLhs+i, destStep2); - VdbeCoverage(v); - } - } - - /* Step 3. The LHS is now known to be non-NULL. Do the binary search - ** of the RHS using the LHS as a probe. If found, the result is - ** true. - */ - if( eType==IN_INDEX_ROWID ){ - /* In this case, the RHS is the ROWID of table b-tree and so we also - ** know that the RHS is non-NULL. Hence, we combine steps 3 and 4 - ** into a single opcode. */ - sqlite3VdbeAddOp3(v, OP_SeekRowid, pExpr->iTable, destIfFalse, rLhs); - VdbeCoverage(v); - addrTruthOp = sqlite3VdbeAddOp0(v, OP_Goto); /* Return True */ - }else{ - sqlite3VdbeAddOp4(v, OP_Affinity, rLhs, nVector, 0, zAff, nVector); - if( destIfFalse==destIfNull ){ - /* Combine Step 3 and Step 5 into a single opcode */ - sqlite3VdbeAddOp4Int(v, OP_NotFound, pExpr->iTable, destIfFalse, - rLhs, nVector); VdbeCoverage(v); - goto sqlite3ExprCodeIN_finished; - } - /* Ordinary Step 3, for the case where FALSE and NULL are distinct */ - addrTruthOp = sqlite3VdbeAddOp4Int(v, OP_Found, pExpr->iTable, 0, - rLhs, nVector); VdbeCoverage(v); - } - - /* Step 4. If the RHS is known to be non-NULL and we did not find - ** an match on the search above, then the result must be FALSE. - */ - if( rRhsHasNull && nVector==1 ){ - sqlite3VdbeAddOp2(v, OP_NotNull, rRhsHasNull, destIfFalse); - VdbeCoverage(v); - } - - /* Step 5. If we do not care about the difference between NULL and - ** FALSE, then just return false. - */ - if( destIfFalse==destIfNull ) sqlite3VdbeGoto(v, destIfFalse); - - /* Step 6: Loop through rows of the RHS. Compare each row to the LHS. - ** If any comparison is NULL, then the result is NULL. If all - ** comparisons are FALSE then the final result is FALSE. - ** - ** For a scalar LHS, it is sufficient to check just the first row - ** of the RHS. - */ - if( destStep6 ) sqlite3VdbeResolveLabel(v, destStep6); - addrTop = sqlite3VdbeAddOp2(v, OP_Rewind, pExpr->iTable, destIfFalse); - VdbeCoverage(v); - if( nVector>1 ){ - destNotNull = sqlite3VdbeMakeLabel(v); - }else{ - /* For nVector==1, combine steps 6 and 7 by immediately returning - ** FALSE if the first comparison is not NULL */ - destNotNull = destIfFalse; - } - for(i=0; i<nVector; i++){ - Expr *p; - CollSeq *pColl; - int r3 = sqlite3GetTempReg(pParse); - p = sqlite3VectorFieldSubexpr(pLeft, i); - pColl = sqlite3ExprCollSeq(pParse, p); - sqlite3VdbeAddOp3(v, OP_Column, pExpr->iTable, i, r3); - sqlite3VdbeAddOp4(v, OP_Ne, rLhs+i, destNotNull, r3, - (void*)pColl, P4_COLLSEQ); - VdbeCoverage(v); - sqlite3ReleaseTempReg(pParse, r3); - } - sqlite3VdbeAddOp2(v, OP_Goto, 0, destIfNull); - if( nVector>1 ){ - sqlite3VdbeResolveLabel(v, destNotNull); - sqlite3VdbeAddOp2(v, OP_Next, pExpr->iTable, addrTop+1); - VdbeCoverage(v); - - /* Step 7: If we reach this point, we know that the result must - ** be false. */ - sqlite3VdbeAddOp2(v, OP_Goto, 0, destIfFalse); - } - - /* Jumps here in order to return true. */ - sqlite3VdbeJumpHere(v, addrTruthOp); - -sqlite3ExprCodeIN_finished: - if( rLhs!=rLhsOrig ) sqlite3ReleaseTempReg(pParse, rLhs); - sqlite3ExprCachePop(pParse); - VdbeComment((v, "end IN expr")); -sqlite3ExprCodeIN_oom_error: - sqlite3DbFree(pParse->db, aiMap); - sqlite3DbFree(pParse->db, zAff); -} -#endif /* SQLITE_OMIT_SUBQUERY */ - -#ifndef SQLITE_OMIT_FLOATING_POINT -/* -** Generate an instruction that will put the floating point -** value described by z[0..n-1] into register iMem. -** -** The z[] string will probably not be zero-terminated. But the -** z[n] character is guaranteed to be something that does not look -** like the continuation of the number. -*/ -static void codeReal(Vdbe *v, const char *z, int negateFlag, int iMem){ - if( ALWAYS(z!=0) ){ - double value; - sqlite3AtoF(z, &value, sqlite3Strlen30(z), SQLITE_UTF8); - assert( !sqlite3IsNaN(value) ); /* The new AtoF never returns NaN */ - if( negateFlag ) value = -value; - sqlite3VdbeAddOp4Dup8(v, OP_Real, 0, iMem, 0, (u8*)&value, P4_REAL); - } -} -#endif - - -/* -** Generate an instruction that will put the integer describe by -** text z[0..n-1] into register iMem. -** -** Expr.u.zToken is always UTF8 and zero-terminated. -*/ -static void codeInteger(Parse *pParse, Expr *pExpr, int negFlag, int iMem){ - Vdbe *v = pParse->pVdbe; - if( pExpr->flags & EP_IntValue ){ - int i = pExpr->u.iValue; - assert( i>=0 ); - if( negFlag ) i = -i; - sqlite3VdbeAddOp2(v, OP_Integer, i, iMem); - }else{ - int c; - i64 value; - const char *z = pExpr->u.zToken; - assert( z!=0 ); - c = sqlite3DecOrHexToI64(z, &value); - if( (c==3 && !negFlag) || (c==2) || (negFlag && value==SMALLEST_INT64)){ -#ifdef SQLITE_OMIT_FLOATING_POINT - sqlite3ErrorMsg(pParse, "oversized integer: %s%s", negFlag ? "-" : "", z); -#else -#ifndef SQLITE_OMIT_HEX_INTEGER - if( sqlite3_strnicmp(z,"0x",2)==0 ){ - sqlite3ErrorMsg(pParse, "hex literal too big: %s%s", negFlag?"-":"",z); - }else -#endif - { - codeReal(v, z, negFlag, iMem); - } -#endif - }else{ - if( negFlag ){ value = c==3 ? SMALLEST_INT64 : -value; } - sqlite3VdbeAddOp4Dup8(v, OP_Int64, 0, iMem, 0, (u8*)&value, P4_INT64); - } - } -} - -/* -** Erase column-cache entry number i -*/ -static void cacheEntryClear(Parse *pParse, int i){ - if( pParse->aColCache[i].tempReg ){ - if( pParse->nTempReg<ArraySize(pParse->aTempReg) ){ - pParse->aTempReg[pParse->nTempReg++] = pParse->aColCache[i].iReg; - } - } - pParse->nColCache--; - if( i<pParse->nColCache ){ - pParse->aColCache[i] = pParse->aColCache[pParse->nColCache]; - } -} - - -/* -** Record in the column cache that a particular column from a -** particular table is stored in a particular register. -*/ -void sqlite3ExprCacheStore(Parse *pParse, int iTab, int iCol, int iReg){ - int i; - int minLru; - int idxLru; - struct yColCache *p; - - /* Unless an error has occurred, register numbers are always positive. */ - assert( iReg>0 || pParse->nErr || pParse->db->mallocFailed ); - assert( iCol>=-1 && iCol<32768 ); /* Finite column numbers */ - - /* The SQLITE_ColumnCache flag disables the column cache. This is used - ** for testing only - to verify that SQLite always gets the same answer - ** with and without the column cache. - */ - if( OptimizationDisabled(pParse->db, SQLITE_ColumnCache) ) return; - - /* First replace any existing entry. - ** - ** Actually, the way the column cache is currently used, we are guaranteed - ** that the object will never already be in cache. Verify this guarantee. - */ -#ifndef NDEBUG - for(i=0, p=pParse->aColCache; i<pParse->nColCache; i++, p++){ - assert( p->iTable!=iTab || p->iColumn!=iCol ); - } -#endif - - /* If the cache is already full, delete the least recently used entry */ - if( pParse->nColCache>=SQLITE_N_COLCACHE ){ - minLru = 0x7fffffff; - idxLru = -1; - for(i=0, p=pParse->aColCache; i<SQLITE_N_COLCACHE; i++, p++){ - if( p->lru<minLru ){ - idxLru = i; - minLru = p->lru; - } - } - p = &pParse->aColCache[idxLru]; - }else{ - p = &pParse->aColCache[pParse->nColCache++]; - } - - /* Add the new entry to the end of the cache */ - p->iLevel = pParse->iCacheLevel; - p->iTable = iTab; - p->iColumn = iCol; - p->iReg = iReg; - p->tempReg = 0; - p->lru = pParse->iCacheCnt++; -} - -/* -** Indicate that registers between iReg..iReg+nReg-1 are being overwritten. -** Purge the range of registers from the column cache. -*/ -void sqlite3ExprCacheRemove(Parse *pParse, int iReg, int nReg){ - int i = 0; - while( i<pParse->nColCache ){ - struct yColCache *p = &pParse->aColCache[i]; - if( p->iReg >= iReg && p->iReg < iReg+nReg ){ - cacheEntryClear(pParse, i); - }else{ - i++; - } - } -} - -/* -** Remember the current column cache context. Any new entries added -** added to the column cache after this call are removed when the -** corresponding pop occurs. -*/ -void sqlite3ExprCachePush(Parse *pParse){ - pParse->iCacheLevel++; -#ifdef SQLITE_DEBUG - if( pParse->db->flags & SQLITE_VdbeAddopTrace ){ - printf("PUSH to %d\n", pParse->iCacheLevel); - } -#endif -} - -/* -** Remove from the column cache any entries that were added since the -** the previous sqlite3ExprCachePush operation. In other words, restore -** the cache to the state it was in prior the most recent Push. -*/ -void sqlite3ExprCachePop(Parse *pParse){ - int i = 0; - assert( pParse->iCacheLevel>=1 ); - pParse->iCacheLevel--; -#ifdef SQLITE_DEBUG - if( pParse->db->flags & SQLITE_VdbeAddopTrace ){ - printf("POP to %d\n", pParse->iCacheLevel); - } -#endif - while( i<pParse->nColCache ){ - if( pParse->aColCache[i].iLevel>pParse->iCacheLevel ){ - cacheEntryClear(pParse, i); - }else{ - i++; - } - } -} - -/* -** When a cached column is reused, make sure that its register is -** no longer available as a temp register. ticket #3879: that same -** register might be in the cache in multiple places, so be sure to -** get them all. -*/ -static void sqlite3ExprCachePinRegister(Parse *pParse, int iReg){ - int i; - struct yColCache *p; - for(i=0, p=pParse->aColCache; i<pParse->nColCache; i++, p++){ - if( p->iReg==iReg ){ - p->tempReg = 0; - } - } -} - -/* Generate code that will load into register regOut a value that is -** appropriate for the iIdxCol-th column of index pIdx. -*/ -void sqlite3ExprCodeLoadIndexColumn( - Parse *pParse, /* The parsing context */ - Index *pIdx, /* The index whose column is to be loaded */ - int iTabCur, /* Cursor pointing to a table row */ - int iIdxCol, /* The column of the index to be loaded */ - int regOut /* Store the index column value in this register */ -){ - i16 iTabCol = pIdx->aiColumn[iIdxCol]; - if( iTabCol==XN_EXPR ){ - assert( pIdx->aColExpr ); - assert( pIdx->aColExpr->nExpr>iIdxCol ); - pParse->iSelfTab = iTabCur + 1; - sqlite3ExprCodeCopy(pParse, pIdx->aColExpr->a[iIdxCol].pExpr, regOut); - pParse->iSelfTab = 0; - }else{ - sqlite3ExprCodeGetColumnOfTable(pParse->pVdbe, pIdx->pTable, iTabCur, - iTabCol, regOut); - } -} - -/* -** Generate code to extract the value of the iCol-th column of a table. -*/ -void sqlite3ExprCodeGetColumnOfTable( - Vdbe *v, /* The VDBE under construction */ - Table *pTab, /* The table containing the value */ - int iTabCur, /* The table cursor. Or the PK cursor for WITHOUT ROWID */ - int iCol, /* Index of the column to extract */ - int regOut /* Extract the value into this register */ -){ - if( pTab==0 ){ - sqlite3VdbeAddOp3(v, OP_Column, iTabCur, iCol, regOut); - return; - } - if( iCol<0 || iCol==pTab->iPKey ){ - sqlite3VdbeAddOp2(v, OP_Rowid, iTabCur, regOut); - }else{ - int op = IsVirtual(pTab) ? OP_VColumn : OP_Column; - int x = iCol; - if( !HasRowid(pTab) && !IsVirtual(pTab) ){ - x = sqlite3ColumnOfIndex(sqlite3PrimaryKeyIndex(pTab), iCol); - } - sqlite3VdbeAddOp3(v, op, iTabCur, x, regOut); - } - if( iCol>=0 ){ - sqlite3ColumnDefault(v, pTab, iCol, regOut); - } -} - -/* -** Generate code that will extract the iColumn-th column from -** table pTab and store the column value in a register. -** -** An effort is made to store the column value in register iReg. This -** is not garanteeed for GetColumn() - the result can be stored in -** any register. But the result is guaranteed to land in register iReg -** for GetColumnToReg(). -** -** There must be an open cursor to pTab in iTable when this routine -** is called. If iColumn<0 then code is generated that extracts the rowid. -*/ -int sqlite3ExprCodeGetColumn( - Parse *pParse, /* Parsing and code generating context */ - Table *pTab, /* Description of the table we are reading from */ - int iColumn, /* Index of the table column */ - int iTable, /* The cursor pointing to the table */ - int iReg, /* Store results here */ - u8 p5 /* P5 value for OP_Column + FLAGS */ -){ - Vdbe *v = pParse->pVdbe; - int i; - struct yColCache *p; - - for(i=0, p=pParse->aColCache; i<pParse->nColCache; i++, p++){ - if( p->iTable==iTable && p->iColumn==iColumn ){ - p->lru = pParse->iCacheCnt++; - sqlite3ExprCachePinRegister(pParse, p->iReg); - return p->iReg; - } - } - assert( v!=0 ); - sqlite3ExprCodeGetColumnOfTable(v, pTab, iTable, iColumn, iReg); - if( p5 ){ - sqlite3VdbeChangeP5(v, p5); - }else{ - sqlite3ExprCacheStore(pParse, iTable, iColumn, iReg); - } - return iReg; -} -void sqlite3ExprCodeGetColumnToReg( - Parse *pParse, /* Parsing and code generating context */ - Table *pTab, /* Description of the table we are reading from */ - int iColumn, /* Index of the table column */ - int iTable, /* The cursor pointing to the table */ - int iReg /* Store results here */ -){ - int r1 = sqlite3ExprCodeGetColumn(pParse, pTab, iColumn, iTable, iReg, 0); - if( r1!=iReg ) sqlite3VdbeAddOp2(pParse->pVdbe, OP_SCopy, r1, iReg); -} - - -/* -** Clear all column cache entries. -*/ -void sqlite3ExprCacheClear(Parse *pParse){ - int i; - -#ifdef SQLITE_DEBUG - if( pParse->db->flags & SQLITE_VdbeAddopTrace ){ - printf("CLEAR\n"); - } -#endif - for(i=0; i<pParse->nColCache; i++){ - if( pParse->aColCache[i].tempReg - && pParse->nTempReg<ArraySize(pParse->aTempReg) - ){ - pParse->aTempReg[pParse->nTempReg++] = pParse->aColCache[i].iReg; - } - } - pParse->nColCache = 0; -} - -/* -** Record the fact that an affinity change has occurred on iCount -** registers starting with iStart. -*/ -void sqlite3ExprCacheAffinityChange(Parse *pParse, int iStart, int iCount){ - sqlite3ExprCacheRemove(pParse, iStart, iCount); -} - -/* -** Generate code to move content from registers iFrom...iFrom+nReg-1 -** over to iTo..iTo+nReg-1. Keep the column cache up-to-date. -*/ -void sqlite3ExprCodeMove(Parse *pParse, int iFrom, int iTo, int nReg){ - assert( iFrom>=iTo+nReg || iFrom+nReg<=iTo ); - sqlite3VdbeAddOp3(pParse->pVdbe, OP_Move, iFrom, iTo, nReg); - sqlite3ExprCacheRemove(pParse, iFrom, nReg); -} - -#if defined(SQLITE_DEBUG) || defined(SQLITE_COVERAGE_TEST) -/* -** Return true if any register in the range iFrom..iTo (inclusive) -** is used as part of the column cache. -** -** This routine is used within assert() and testcase() macros only -** and does not appear in a normal build. -*/ -static int usedAsColumnCache(Parse *pParse, int iFrom, int iTo){ - int i; - struct yColCache *p; - for(i=0, p=pParse->aColCache; i<pParse->nColCache; i++, p++){ - int r = p->iReg; - if( r>=iFrom && r<=iTo ) return 1; /*NO_TEST*/ - } - return 0; -} -#endif /* SQLITE_DEBUG || SQLITE_COVERAGE_TEST */ - - -/* -** Convert a scalar expression node to a TK_REGISTER referencing -** register iReg. The caller must ensure that iReg already contains -** the correct value for the expression. -*/ -static void exprToRegister(Expr *p, int iReg){ - p->op2 = p->op; - p->op = TK_REGISTER; - p->iTable = iReg; - ExprClearProperty(p, EP_Skip); -} - -/* -** Evaluate an expression (either a vector or a scalar expression) and store -** the result in continguous temporary registers. Return the index of -** the first register used to store the result. -** -** If the returned result register is a temporary scalar, then also write -** that register number into *piFreeable. If the returned result register -** is not a temporary or if the expression is a vector set *piFreeable -** to 0. -*/ -static int exprCodeVector(Parse *pParse, Expr *p, int *piFreeable){ - int iResult; - int nResult = sqlite3ExprVectorSize(p); - if( nResult==1 ){ - iResult = sqlite3ExprCodeTemp(pParse, p, piFreeable); - }else{ - *piFreeable = 0; - if( p->op==TK_SELECT ){ -#if SQLITE_OMIT_SUBQUERY - iResult = 0; -#else - iResult = sqlite3CodeSubselect(pParse, p, 0, 0); -#endif - }else{ - int i; - iResult = pParse->nMem+1; - pParse->nMem += nResult; - for(i=0; i<nResult; i++){ - sqlite3ExprCodeFactorable(pParse, p->x.pList->a[i].pExpr, i+iResult); - } - } - } - return iResult; -} - - -/* -** Generate code into the current Vdbe to evaluate the given -** expression. Attempt to store the results in register "target". -** Return the register where results are stored. -** -** With this routine, there is no guarantee that results will -** be stored in target. The result might be stored in some other -** register if it is convenient to do so. The calling function -** must check the return code and move the results to the desired -** register. -*/ -int sqlite3ExprCodeTarget(Parse *pParse, Expr *pExpr, int target){ - Vdbe *v = pParse->pVdbe; /* The VM under construction */ - int op; /* The opcode being coded */ - int inReg = target; /* Results stored in register inReg */ - int regFree1 = 0; /* If non-zero free this temporary register */ - int regFree2 = 0; /* If non-zero free this temporary register */ - int r1, r2; /* Various register numbers */ - Expr tempX; /* Temporary expression node */ - int p5 = 0; - - assert( target>0 && target<=pParse->nMem ); - if( v==0 ){ - assert( pParse->db->mallocFailed ); - return 0; - } - -expr_code_doover: - if( pExpr==0 ){ - op = TK_NULL; - }else{ - op = pExpr->op; - } - switch( op ){ - case TK_AGG_COLUMN: { - AggInfo *pAggInfo = pExpr->pAggInfo; - struct AggInfo_col *pCol = &pAggInfo->aCol[pExpr->iAgg]; - if( !pAggInfo->directMode ){ - assert( pCol->iMem>0 ); - return pCol->iMem; - }else if( pAggInfo->useSortingIdx ){ - sqlite3VdbeAddOp3(v, OP_Column, pAggInfo->sortingIdxPTab, - pCol->iSorterColumn, target); - return target; - } - /* Otherwise, fall thru into the TK_COLUMN case */ - } - case TK_COLUMN: { - int iTab = pExpr->iTable; - if( iTab<0 ){ - if( pParse->iSelfTab<0 ){ - /* Generating CHECK constraints or inserting into partial index */ - return pExpr->iColumn - pParse->iSelfTab; - }else{ - /* Coding an expression that is part of an index where column names - ** in the index refer to the table to which the index belongs */ - iTab = pParse->iSelfTab - 1; - } - } - return sqlite3ExprCodeGetColumn(pParse, pExpr->pTab, - pExpr->iColumn, iTab, target, - pExpr->op2); - } - case TK_INTEGER: { - codeInteger(pParse, pExpr, 0, target); - return target; - } - case TK_TRUEFALSE: { - sqlite3VdbeAddOp2(v, OP_Integer, sqlite3ExprTruthValue(pExpr), target); - return target; - } -#ifndef SQLITE_OMIT_FLOATING_POINT - case TK_FLOAT: { - assert( !ExprHasProperty(pExpr, EP_IntValue) ); - codeReal(v, pExpr->u.zToken, 0, target); - return target; - } -#endif - case TK_STRING: { - assert( !ExprHasProperty(pExpr, EP_IntValue) ); - sqlite3VdbeLoadString(v, target, pExpr->u.zToken); - return target; - } - case TK_NULL: { - sqlite3VdbeAddOp2(v, OP_Null, 0, target); - return target; - } -#ifndef SQLITE_OMIT_BLOB_LITERAL - case TK_BLOB: { - int n; - const char *z; - char *zBlob; - assert( !ExprHasProperty(pExpr, EP_IntValue) ); - assert( pExpr->u.zToken[0]=='x' || pExpr->u.zToken[0]=='X' ); - assert( pExpr->u.zToken[1]=='\'' ); - z = &pExpr->u.zToken[2]; - n = sqlite3Strlen30(z) - 1; - assert( z[n]=='\'' ); - zBlob = sqlite3HexToBlob(sqlite3VdbeDb(v), z, n); - sqlite3VdbeAddOp4(v, OP_Blob, n/2, target, 0, zBlob, P4_DYNAMIC); - return target; - } -#endif - case TK_VARIABLE: { - assert( !ExprHasProperty(pExpr, EP_IntValue) ); - assert( pExpr->u.zToken!=0 ); - assert( pExpr->u.zToken[0]!=0 ); - sqlite3VdbeAddOp2(v, OP_Variable, pExpr->iColumn, target); - if( pExpr->u.zToken[1]!=0 ){ - const char *z = sqlite3VListNumToName(pParse->pVList, pExpr->iColumn); - assert( pExpr->u.zToken[0]=='?' || strcmp(pExpr->u.zToken, z)==0 ); - pParse->pVList[0] = 0; /* Indicate VList may no longer be enlarged */ - sqlite3VdbeAppendP4(v, (char*)z, P4_STATIC); - } - return target; - } - case TK_REGISTER: { - return pExpr->iTable; - } -#ifndef SQLITE_OMIT_CAST - case TK_CAST: { - /* Expressions of the form: CAST(pLeft AS token) */ - inReg = sqlite3ExprCodeTarget(pParse, pExpr->pLeft, target); - if( inReg!=target ){ - sqlite3VdbeAddOp2(v, OP_SCopy, inReg, target); - inReg = target; - } - sqlite3VdbeAddOp2(v, OP_Cast, target, - sqlite3AffinityType(pExpr->u.zToken, 0)); - testcase( usedAsColumnCache(pParse, inReg, inReg) ); - sqlite3ExprCacheAffinityChange(pParse, inReg, 1); - return inReg; - } -#endif /* SQLITE_OMIT_CAST */ - case TK_IS: - case TK_ISNOT: - op = (op==TK_IS) ? TK_EQ : TK_NE; - p5 = SQLITE_NULLEQ; - /* fall-through */ - case TK_LT: - case TK_LE: - case TK_GT: - case TK_GE: - case TK_NE: - case TK_EQ: { - Expr *pLeft = pExpr->pLeft; - if( sqlite3ExprIsVector(pLeft) ){ - codeVectorCompare(pParse, pExpr, target, op, p5); - }else{ - r1 = sqlite3ExprCodeTemp(pParse, pLeft, ®Free1); - r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, ®Free2); - codeCompare(pParse, pLeft, pExpr->pRight, op, - r1, r2, inReg, SQLITE_STOREP2 | p5); - assert(TK_LT==OP_Lt); testcase(op==OP_Lt); VdbeCoverageIf(v,op==OP_Lt); - assert(TK_LE==OP_Le); testcase(op==OP_Le); VdbeCoverageIf(v,op==OP_Le); - assert(TK_GT==OP_Gt); testcase(op==OP_Gt); VdbeCoverageIf(v,op==OP_Gt); - assert(TK_GE==OP_Ge); testcase(op==OP_Ge); VdbeCoverageIf(v,op==OP_Ge); - assert(TK_EQ==OP_Eq); testcase(op==OP_Eq); VdbeCoverageIf(v,op==OP_Eq); - assert(TK_NE==OP_Ne); testcase(op==OP_Ne); VdbeCoverageIf(v,op==OP_Ne); - testcase( regFree1==0 ); - testcase( regFree2==0 ); - } - break; - } - case TK_AND: - case TK_OR: - case TK_PLUS: - case TK_STAR: - case TK_MINUS: - case TK_REM: - case TK_BITAND: - case TK_BITOR: - case TK_SLASH: - case TK_LSHIFT: - case TK_RSHIFT: - case TK_CONCAT: { - assert( TK_AND==OP_And ); testcase( op==TK_AND ); - assert( TK_OR==OP_Or ); testcase( op==TK_OR ); - assert( TK_PLUS==OP_Add ); testcase( op==TK_PLUS ); - assert( TK_MINUS==OP_Subtract ); testcase( op==TK_MINUS ); - assert( TK_REM==OP_Remainder ); testcase( op==TK_REM ); - assert( TK_BITAND==OP_BitAnd ); testcase( op==TK_BITAND ); - assert( TK_BITOR==OP_BitOr ); testcase( op==TK_BITOR ); - assert( TK_SLASH==OP_Divide ); testcase( op==TK_SLASH ); - assert( TK_LSHIFT==OP_ShiftLeft ); testcase( op==TK_LSHIFT ); - assert( TK_RSHIFT==OP_ShiftRight ); testcase( op==TK_RSHIFT ); - assert( TK_CONCAT==OP_Concat ); testcase( op==TK_CONCAT ); - r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1); - r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, ®Free2); - sqlite3VdbeAddOp3(v, op, r2, r1, target); - testcase( regFree1==0 ); - testcase( regFree2==0 ); - break; - } - case TK_UMINUS: { - Expr *pLeft = pExpr->pLeft; - assert( pLeft ); - if( pLeft->op==TK_INTEGER ){ - codeInteger(pParse, pLeft, 1, target); - return target; -#ifndef SQLITE_OMIT_FLOATING_POINT - }else if( pLeft->op==TK_FLOAT ){ - assert( !ExprHasProperty(pExpr, EP_IntValue) ); - codeReal(v, pLeft->u.zToken, 1, target); - return target; -#endif - }else{ - tempX.op = TK_INTEGER; - tempX.flags = EP_IntValue|EP_TokenOnly; - tempX.u.iValue = 0; - r1 = sqlite3ExprCodeTemp(pParse, &tempX, ®Free1); - r2 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free2); - sqlite3VdbeAddOp3(v, OP_Subtract, r2, r1, target); - testcase( regFree2==0 ); - } - break; - } - case TK_BITNOT: - case TK_NOT: { - assert( TK_BITNOT==OP_BitNot ); testcase( op==TK_BITNOT ); - assert( TK_NOT==OP_Not ); testcase( op==TK_NOT ); - r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1); - testcase( regFree1==0 ); - sqlite3VdbeAddOp2(v, op, r1, inReg); - break; - } - case TK_TRUTH: { - int isTrue; /* IS TRUE or IS NOT TRUE */ - int bNormal; /* IS TRUE or IS FALSE */ - r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1); - testcase( regFree1==0 ); - isTrue = sqlite3ExprTruthValue(pExpr->pRight); - bNormal = pExpr->op2==TK_IS; - testcase( isTrue && bNormal); - testcase( !isTrue && bNormal); - sqlite3VdbeAddOp4Int(v, OP_IsTrue, r1, inReg, !isTrue, isTrue ^ bNormal); - break; - } - case TK_ISNULL: - case TK_NOTNULL: { - int addr; - assert( TK_ISNULL==OP_IsNull ); testcase( op==TK_ISNULL ); - assert( TK_NOTNULL==OP_NotNull ); testcase( op==TK_NOTNULL ); - sqlite3VdbeAddOp2(v, OP_Integer, 1, target); - r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1); - testcase( regFree1==0 ); - addr = sqlite3VdbeAddOp1(v, op, r1); - VdbeCoverageIf(v, op==TK_ISNULL); - VdbeCoverageIf(v, op==TK_NOTNULL); - sqlite3VdbeAddOp2(v, OP_Integer, 0, target); - sqlite3VdbeJumpHere(v, addr); - break; - } - case TK_AGG_FUNCTION: { - AggInfo *pInfo = pExpr->pAggInfo; - if( pInfo==0 ){ - assert( !ExprHasProperty(pExpr, EP_IntValue) ); - sqlite3ErrorMsg(pParse, "misuse of aggregate: %s()", pExpr->u.zToken); - }else{ - return pInfo->aFunc[pExpr->iAgg].iMem; - } - break; - } - case TK_FUNCTION: { - ExprList *pFarg; /* List of function arguments */ - int nFarg; /* Number of function arguments */ - FuncDef *pDef; /* The function definition object */ - const char *zId; /* The function name */ - u32 constMask = 0; /* Mask of function arguments that are constant */ - int i; /* Loop counter */ - sqlite3 *db = pParse->db; /* The database connection */ - u8 enc = ENC(db); /* The text encoding used by this database */ - CollSeq *pColl = 0; /* A collating sequence */ - - if( ConstFactorOk(pParse) && sqlite3ExprIsConstantNotJoin(pExpr) ){ - /* SQL functions can be expensive. So try to move constant functions - ** out of the inner loop, even if that means an extra OP_Copy. */ - return sqlite3ExprCodeAtInit(pParse, pExpr, -1); - } - assert( !ExprHasProperty(pExpr, EP_xIsSelect) ); - if( ExprHasProperty(pExpr, EP_TokenOnly) ){ - pFarg = 0; - }else{ - pFarg = pExpr->x.pList; - } - nFarg = pFarg ? pFarg->nExpr : 0; - assert( !ExprHasProperty(pExpr, EP_IntValue) ); - zId = pExpr->u.zToken; - pDef = sqlite3FindFunction(db, zId, nFarg, enc, 0); -#ifdef SQLITE_ENABLE_UNKNOWN_SQL_FUNCTION - if( pDef==0 && pParse->explain ){ - pDef = sqlite3FindFunction(db, "unknown", nFarg, enc, 0); - } -#endif - if( pDef==0 || pDef->xFinalize!=0 ){ - sqlite3ErrorMsg(pParse, "unknown function: %s()", zId); - break; - } - - /* Attempt a direct implementation of the built-in COALESCE() and - ** IFNULL() functions. This avoids unnecessary evaluation of - ** arguments past the first non-NULL argument. - */ - if( pDef->funcFlags & SQLITE_FUNC_COALESCE ){ - int endCoalesce = sqlite3VdbeMakeLabel(v); - assert( nFarg>=2 ); - sqlite3ExprCode(pParse, pFarg->a[0].pExpr, target); - for(i=1; i<nFarg; i++){ - sqlite3VdbeAddOp2(v, OP_NotNull, target, endCoalesce); - VdbeCoverage(v); - sqlite3ExprCacheRemove(pParse, target, 1); - sqlite3ExprCachePush(pParse); - sqlite3ExprCode(pParse, pFarg->a[i].pExpr, target); - sqlite3ExprCachePop(pParse); - } - sqlite3VdbeResolveLabel(v, endCoalesce); - break; - } - - /* The UNLIKELY() function is a no-op. The result is the value - ** of the first argument. - */ - if( pDef->funcFlags & SQLITE_FUNC_UNLIKELY ){ - assert( nFarg>=1 ); - return sqlite3ExprCodeTarget(pParse, pFarg->a[0].pExpr, target); - } - -#ifdef SQLITE_DEBUG - /* The AFFINITY() function evaluates to a string that describes - ** the type affinity of the argument. This is used for testing of - ** the SQLite type logic. - */ - if( pDef->funcFlags & SQLITE_FUNC_AFFINITY ){ - const char *azAff[] = { "blob", "text", "numeric", "integer", "real" }; - char aff; - assert( nFarg==1 ); - aff = sqlite3ExprAffinity(pFarg->a[0].pExpr); - sqlite3VdbeLoadString(v, target, - aff ? azAff[aff-SQLITE_AFF_BLOB] : "none"); - return target; - } -#endif - - for(i=0; i<nFarg; i++){ - if( i<32 && sqlite3ExprIsConstant(pFarg->a[i].pExpr) ){ - testcase( i==31 ); - constMask |= MASKBIT32(i); - } - if( (pDef->funcFlags & SQLITE_FUNC_NEEDCOLL)!=0 && !pColl ){ - pColl = sqlite3ExprCollSeq(pParse, pFarg->a[i].pExpr); - } - } - if( pFarg ){ - if( constMask ){ - r1 = pParse->nMem+1; - pParse->nMem += nFarg; - }else{ - r1 = sqlite3GetTempRange(pParse, nFarg); - } - - /* For length() and typeof() functions with a column argument, - ** set the P5 parameter to the OP_Column opcode to OPFLAG_LENGTHARG - ** or OPFLAG_TYPEOFARG respectively, to avoid unnecessary data - ** loading. - */ - if( (pDef->funcFlags & (SQLITE_FUNC_LENGTH|SQLITE_FUNC_TYPEOF))!=0 ){ - u8 exprOp; - assert( nFarg==1 ); - assert( pFarg->a[0].pExpr!=0 ); - exprOp = pFarg->a[0].pExpr->op; - if( exprOp==TK_COLUMN || exprOp==TK_AGG_COLUMN ){ - assert( SQLITE_FUNC_LENGTH==OPFLAG_LENGTHARG ); - assert( SQLITE_FUNC_TYPEOF==OPFLAG_TYPEOFARG ); - testcase( pDef->funcFlags & OPFLAG_LENGTHARG ); - pFarg->a[0].pExpr->op2 = - pDef->funcFlags & (OPFLAG_LENGTHARG|OPFLAG_TYPEOFARG); - } - } - - sqlite3ExprCachePush(pParse); /* Ticket 2ea2425d34be */ - sqlite3ExprCodeExprList(pParse, pFarg, r1, 0, - SQLITE_ECEL_DUP|SQLITE_ECEL_FACTOR); - sqlite3ExprCachePop(pParse); /* Ticket 2ea2425d34be */ - }else{ - r1 = 0; - } -#ifndef SQLITE_OMIT_VIRTUALTABLE - /* Possibly overload the function if the first argument is - ** a virtual table column. - ** - ** For infix functions (LIKE, GLOB, REGEXP, and MATCH) use the - ** second argument, not the first, as the argument to test to - ** see if it is a column in a virtual table. This is done because - ** the left operand of infix functions (the operand we want to - ** control overloading) ends up as the second argument to the - ** function. The expression "A glob B" is equivalent to - ** "glob(B,A). We want to use the A in "A glob B" to test - ** for function overloading. But we use the B term in "glob(B,A)". - */ - if( nFarg>=2 && (pExpr->flags & EP_InfixFunc) ){ - pDef = sqlite3VtabOverloadFunction(db, pDef, nFarg, pFarg->a[1].pExpr); - }else if( nFarg>0 ){ - pDef = sqlite3VtabOverloadFunction(db, pDef, nFarg, pFarg->a[0].pExpr); - } -#endif - if( pDef->funcFlags & SQLITE_FUNC_NEEDCOLL ){ - if( !pColl ) pColl = db->pDfltColl; - sqlite3VdbeAddOp4(v, OP_CollSeq, 0, 0, 0, (char *)pColl, P4_COLLSEQ); - } -#ifdef SQLITE_ENABLE_OFFSET_SQL_FUNC - if( pDef->funcFlags & SQLITE_FUNC_OFFSET ){ - Expr *pArg = pFarg->a[0].pExpr; - if( pArg->op==TK_COLUMN ){ - sqlite3VdbeAddOp3(v, OP_Offset, pArg->iTable, pArg->iColumn, target); - }else{ - sqlite3VdbeAddOp2(v, OP_Null, 0, target); - } - }else -#endif - { - sqlite3VdbeAddOp4(v, pParse->iSelfTab ? OP_PureFunc0 : OP_Function0, - constMask, r1, target, (char*)pDef, P4_FUNCDEF); - sqlite3VdbeChangeP5(v, (u8)nFarg); - } - if( nFarg && constMask==0 ){ - sqlite3ReleaseTempRange(pParse, r1, nFarg); - } - return target; - } -#ifndef SQLITE_OMIT_SUBQUERY - case TK_EXISTS: - case TK_SELECT: { - int nCol; - testcase( op==TK_EXISTS ); - testcase( op==TK_SELECT ); - if( op==TK_SELECT && (nCol = pExpr->x.pSelect->pEList->nExpr)!=1 ){ - sqlite3SubselectError(pParse, nCol, 1); - }else{ - return sqlite3CodeSubselect(pParse, pExpr, 0, 0); - } - break; - } - case TK_SELECT_COLUMN: { - int n; - if( pExpr->pLeft->iTable==0 ){ - pExpr->pLeft->iTable = sqlite3CodeSubselect(pParse, pExpr->pLeft, 0, 0); - } - assert( pExpr->iTable==0 || pExpr->pLeft->op==TK_SELECT ); - if( pExpr->iTable - && pExpr->iTable!=(n = sqlite3ExprVectorSize(pExpr->pLeft)) - ){ - sqlite3ErrorMsg(pParse, "%d columns assigned %d values", - pExpr->iTable, n); - } - return pExpr->pLeft->iTable + pExpr->iColumn; - } - case TK_IN: { - int destIfFalse = sqlite3VdbeMakeLabel(v); - int destIfNull = sqlite3VdbeMakeLabel(v); - sqlite3VdbeAddOp2(v, OP_Null, 0, target); - sqlite3ExprCodeIN(pParse, pExpr, destIfFalse, destIfNull); - sqlite3VdbeAddOp2(v, OP_Integer, 1, target); - sqlite3VdbeResolveLabel(v, destIfFalse); - sqlite3VdbeAddOp2(v, OP_AddImm, target, 0); - sqlite3VdbeResolveLabel(v, destIfNull); - return target; - } -#endif /* SQLITE_OMIT_SUBQUERY */ - - - /* - ** x BETWEEN y AND z - ** - ** This is equivalent to - ** - ** x>=y AND x<=z - ** - ** X is stored in pExpr->pLeft. - ** Y is stored in pExpr->pList->a[0].pExpr. - ** Z is stored in pExpr->pList->a[1].pExpr. - */ - case TK_BETWEEN: { - exprCodeBetween(pParse, pExpr, target, 0, 0); - return target; - } - case TK_SPAN: - case TK_COLLATE: - case TK_UPLUS: { - pExpr = pExpr->pLeft; - goto expr_code_doover; /* 2018-04-28: Prevent deep recursion. OSSFuzz. */ - } - - case TK_TRIGGER: { - /* If the opcode is TK_TRIGGER, then the expression is a reference - ** to a column in the new.* or old.* pseudo-tables available to - ** trigger programs. In this case Expr.iTable is set to 1 for the - ** new.* pseudo-table, or 0 for the old.* pseudo-table. Expr.iColumn - ** is set to the column of the pseudo-table to read, or to -1 to - ** read the rowid field. - ** - ** The expression is implemented using an OP_Param opcode. The p1 - ** parameter is set to 0 for an old.rowid reference, or to (i+1) - ** to reference another column of the old.* pseudo-table, where - ** i is the index of the column. For a new.rowid reference, p1 is - ** set to (n+1), where n is the number of columns in each pseudo-table. - ** For a reference to any other column in the new.* pseudo-table, p1 - ** is set to (n+2+i), where n and i are as defined previously. For - ** example, if the table on which triggers are being fired is - ** declared as: - ** - ** CREATE TABLE t1(a, b); - ** - ** Then p1 is interpreted as follows: - ** - ** p1==0 -> old.rowid p1==3 -> new.rowid - ** p1==1 -> old.a p1==4 -> new.a - ** p1==2 -> old.b p1==5 -> new.b - */ - Table *pTab = pExpr->pTab; - int p1 = pExpr->iTable * (pTab->nCol+1) + 1 + pExpr->iColumn; - - assert( pExpr->iTable==0 || pExpr->iTable==1 ); - assert( pExpr->iColumn>=-1 && pExpr->iColumn<pTab->nCol ); - assert( pTab->iPKey<0 || pExpr->iColumn!=pTab->iPKey ); - assert( p1>=0 && p1<(pTab->nCol*2+2) ); - - sqlite3VdbeAddOp2(v, OP_Param, p1, target); - VdbeComment((v, "r[%d]=%s.%s", target, - (pExpr->iTable ? "new" : "old"), - (pExpr->iColumn<0 ? "rowid" : pExpr->pTab->aCol[pExpr->iColumn].zName) - )); - -#ifndef SQLITE_OMIT_FLOATING_POINT - /* If the column has REAL affinity, it may currently be stored as an - ** integer. Use OP_RealAffinity to make sure it is really real. - ** - ** EVIDENCE-OF: R-60985-57662 SQLite will convert the value back to - ** floating point when extracting it from the record. */ - if( pExpr->iColumn>=0 - && pTab->aCol[pExpr->iColumn].affinity==SQLITE_AFF_REAL - ){ - sqlite3VdbeAddOp1(v, OP_RealAffinity, target); - } -#endif - break; - } - - case TK_VECTOR: { - sqlite3ErrorMsg(pParse, "row value misused"); - break; - } - - case TK_IF_NULL_ROW: { - int addrINR; - addrINR = sqlite3VdbeAddOp1(v, OP_IfNullRow, pExpr->iTable); - sqlite3ExprCachePush(pParse); - inReg = sqlite3ExprCodeTarget(pParse, pExpr->pLeft, target); - sqlite3ExprCachePop(pParse); - sqlite3VdbeJumpHere(v, addrINR); - sqlite3VdbeChangeP3(v, addrINR, inReg); - break; - } - - /* - ** Form A: - ** CASE x WHEN e1 THEN r1 WHEN e2 THEN r2 ... WHEN eN THEN rN ELSE y END - ** - ** Form B: - ** CASE WHEN e1 THEN r1 WHEN e2 THEN r2 ... WHEN eN THEN rN ELSE y END - ** - ** Form A is can be transformed into the equivalent form B as follows: - ** CASE WHEN x=e1 THEN r1 WHEN x=e2 THEN r2 ... - ** WHEN x=eN THEN rN ELSE y END - ** - ** X (if it exists) is in pExpr->pLeft. - ** Y is in the last element of pExpr->x.pList if pExpr->x.pList->nExpr is - ** odd. The Y is also optional. If the number of elements in x.pList - ** is even, then Y is omitted and the "otherwise" result is NULL. - ** Ei is in pExpr->pList->a[i*2] and Ri is pExpr->pList->a[i*2+1]. - ** - ** The result of the expression is the Ri for the first matching Ei, - ** or if there is no matching Ei, the ELSE term Y, or if there is - ** no ELSE term, NULL. - */ - default: assert( op==TK_CASE ); { - int endLabel; /* GOTO label for end of CASE stmt */ - int nextCase; /* GOTO label for next WHEN clause */ - int nExpr; /* 2x number of WHEN terms */ - int i; /* Loop counter */ - ExprList *pEList; /* List of WHEN terms */ - struct ExprList_item *aListelem; /* Array of WHEN terms */ - Expr opCompare; /* The X==Ei expression */ - Expr *pX; /* The X expression */ - Expr *pTest = 0; /* X==Ei (form A) or just Ei (form B) */ - VVA_ONLY( int iCacheLevel = pParse->iCacheLevel; ) - - assert( !ExprHasProperty(pExpr, EP_xIsSelect) && pExpr->x.pList ); - assert(pExpr->x.pList->nExpr > 0); - pEList = pExpr->x.pList; - aListelem = pEList->a; - nExpr = pEList->nExpr; - endLabel = sqlite3VdbeMakeLabel(v); - if( (pX = pExpr->pLeft)!=0 ){ - tempX = *pX; - testcase( pX->op==TK_COLUMN ); - exprToRegister(&tempX, exprCodeVector(pParse, &tempX, ®Free1)); - testcase( regFree1==0 ); - memset(&opCompare, 0, sizeof(opCompare)); - opCompare.op = TK_EQ; - opCompare.pLeft = &tempX; - pTest = &opCompare; - /* Ticket b351d95f9cd5ef17e9d9dbae18f5ca8611190001: - ** The value in regFree1 might get SCopy-ed into the file result. - ** So make sure that the regFree1 register is not reused for other - ** purposes and possibly overwritten. */ - regFree1 = 0; - } - for(i=0; i<nExpr-1; i=i+2){ - sqlite3ExprCachePush(pParse); - if( pX ){ - assert( pTest!=0 ); - opCompare.pRight = aListelem[i].pExpr; - }else{ - pTest = aListelem[i].pExpr; - } - nextCase = sqlite3VdbeMakeLabel(v); - testcase( pTest->op==TK_COLUMN ); - sqlite3ExprIfFalse(pParse, pTest, nextCase, SQLITE_JUMPIFNULL); - testcase( aListelem[i+1].pExpr->op==TK_COLUMN ); - sqlite3ExprCode(pParse, aListelem[i+1].pExpr, target); - sqlite3VdbeGoto(v, endLabel); - sqlite3ExprCachePop(pParse); - sqlite3VdbeResolveLabel(v, nextCase); - } - if( (nExpr&1)!=0 ){ - sqlite3ExprCachePush(pParse); - sqlite3ExprCode(pParse, pEList->a[nExpr-1].pExpr, target); - sqlite3ExprCachePop(pParse); - }else{ - sqlite3VdbeAddOp2(v, OP_Null, 0, target); - } - assert( pParse->db->mallocFailed || pParse->nErr>0 - || pParse->iCacheLevel==iCacheLevel ); - sqlite3VdbeResolveLabel(v, endLabel); - break; - } -#ifndef SQLITE_OMIT_TRIGGER - case TK_RAISE: { - assert( pExpr->affinity==OE_Rollback - || pExpr->affinity==OE_Abort - || pExpr->affinity==OE_Fail - || pExpr->affinity==OE_Ignore - ); - if( !pParse->pTriggerTab ){ - sqlite3ErrorMsg(pParse, - "RAISE() may only be used within a trigger-program"); - return 0; - } - if( pExpr->affinity==OE_Abort ){ - sqlite3MayAbort(pParse); - } - assert( !ExprHasProperty(pExpr, EP_IntValue) ); - if( pExpr->affinity==OE_Ignore ){ - sqlite3VdbeAddOp4( - v, OP_Halt, SQLITE_OK, OE_Ignore, 0, pExpr->u.zToken,0); - VdbeCoverage(v); - }else{ - sqlite3HaltConstraint(pParse, SQLITE_CONSTRAINT_TRIGGER, - pExpr->affinity, pExpr->u.zToken, 0, 0); - } - - break; - } -#endif - } - sqlite3ReleaseTempReg(pParse, regFree1); - sqlite3ReleaseTempReg(pParse, regFree2); - return inReg; -} - -/* -** Factor out the code of the given expression to initialization time. -** -** If regDest>=0 then the result is always stored in that register and the -** result is not reusable. If regDest<0 then this routine is free to -** store the value whereever it wants. The register where the expression -** is stored is returned. When regDest<0, two identical expressions will -** code to the same register. -*/ -int sqlite3ExprCodeAtInit( - Parse *pParse, /* Parsing context */ - Expr *pExpr, /* The expression to code when the VDBE initializes */ - int regDest /* Store the value in this register */ -){ - ExprList *p; - assert( ConstFactorOk(pParse) ); - p = pParse->pConstExpr; - if( regDest<0 && p ){ - struct ExprList_item *pItem; - int i; - for(pItem=p->a, i=p->nExpr; i>0; pItem++, i--){ - if( pItem->reusable && sqlite3ExprCompare(0,pItem->pExpr,pExpr,-1)==0 ){ - return pItem->u.iConstExprReg; - } - } - } - pExpr = sqlite3ExprDup(pParse->db, pExpr, 0); - p = sqlite3ExprListAppend(pParse, p, pExpr); - if( p ){ - struct ExprList_item *pItem = &p->a[p->nExpr-1]; - pItem->reusable = regDest<0; - if( regDest<0 ) regDest = ++pParse->nMem; - pItem->u.iConstExprReg = regDest; - } - pParse->pConstExpr = p; - return regDest; -} - -/* -** Generate code to evaluate an expression and store the results -** into a register. Return the register number where the results -** are stored. -** -** If the register is a temporary register that can be deallocated, -** then write its number into *pReg. If the result register is not -** a temporary, then set *pReg to zero. -** -** If pExpr is a constant, then this routine might generate this -** code to fill the register in the initialization section of the -** VDBE program, in order to factor it out of the evaluation loop. -*/ -int sqlite3ExprCodeTemp(Parse *pParse, Expr *pExpr, int *pReg){ - int r2; - pExpr = sqlite3ExprSkipCollate(pExpr); - if( ConstFactorOk(pParse) - && pExpr->op!=TK_REGISTER - && sqlite3ExprIsConstantNotJoin(pExpr) - ){ - *pReg = 0; - r2 = sqlite3ExprCodeAtInit(pParse, pExpr, -1); - }else{ - int r1 = sqlite3GetTempReg(pParse); - r2 = sqlite3ExprCodeTarget(pParse, pExpr, r1); - if( r2==r1 ){ - *pReg = r1; - }else{ - sqlite3ReleaseTempReg(pParse, r1); - *pReg = 0; - } - } - return r2; -} - -/* -** Generate code that will evaluate expression pExpr and store the -** results in register target. The results are guaranteed to appear -** in register target. -*/ -void sqlite3ExprCode(Parse *pParse, Expr *pExpr, int target){ - int inReg; - - assert( target>0 && target<=pParse->nMem ); - if( pExpr && pExpr->op==TK_REGISTER ){ - sqlite3VdbeAddOp2(pParse->pVdbe, OP_Copy, pExpr->iTable, target); - }else{ - inReg = sqlite3ExprCodeTarget(pParse, pExpr, target); - assert( pParse->pVdbe!=0 || pParse->db->mallocFailed ); - if( inReg!=target && pParse->pVdbe ){ - sqlite3VdbeAddOp2(pParse->pVdbe, OP_SCopy, inReg, target); - } - } -} - -/* -** Make a transient copy of expression pExpr and then code it using -** sqlite3ExprCode(). This routine works just like sqlite3ExprCode() -** except that the input expression is guaranteed to be unchanged. -*/ -void sqlite3ExprCodeCopy(Parse *pParse, Expr *pExpr, int target){ - sqlite3 *db = pParse->db; - pExpr = sqlite3ExprDup(db, pExpr, 0); - if( !db->mallocFailed ) sqlite3ExprCode(pParse, pExpr, target); - sqlite3ExprDelete(db, pExpr); -} - -/* -** Generate code that will evaluate expression pExpr and store the -** results in register target. The results are guaranteed to appear -** in register target. If the expression is constant, then this routine -** might choose to code the expression at initialization time. -*/ -void sqlite3ExprCodeFactorable(Parse *pParse, Expr *pExpr, int target){ - if( pParse->okConstFactor && sqlite3ExprIsConstant(pExpr) ){ - sqlite3ExprCodeAtInit(pParse, pExpr, target); - }else{ - sqlite3ExprCode(pParse, pExpr, target); - } -} - -/* -** Generate code that evaluates the given expression and puts the result -** in register target. -** -** Also make a copy of the expression results into another "cache" register -** and modify the expression so that the next time it is evaluated, -** the result is a copy of the cache register. -** -** This routine is used for expressions that are used multiple -** times. They are evaluated once and the results of the expression -** are reused. -*/ -void sqlite3ExprCodeAndCache(Parse *pParse, Expr *pExpr, int target){ - Vdbe *v = pParse->pVdbe; - int iMem; - - assert( target>0 ); - assert( pExpr->op!=TK_REGISTER ); - sqlite3ExprCode(pParse, pExpr, target); - iMem = ++pParse->nMem; - sqlite3VdbeAddOp2(v, OP_Copy, target, iMem); - exprToRegister(pExpr, iMem); -} - -/* -** Generate code that pushes the value of every element of the given -** expression list into a sequence of registers beginning at target. -** -** Return the number of elements evaluated. The number returned will -** usually be pList->nExpr but might be reduced if SQLITE_ECEL_OMITREF -** is defined. -** -** The SQLITE_ECEL_DUP flag prevents the arguments from being -** filled using OP_SCopy. OP_Copy must be used instead. -** -** The SQLITE_ECEL_FACTOR argument allows constant arguments to be -** factored out into initialization code. -** -** The SQLITE_ECEL_REF flag means that expressions in the list with -** ExprList.a[].u.x.iOrderByCol>0 have already been evaluated and stored -** in registers at srcReg, and so the value can be copied from there. -** If SQLITE_ECEL_OMITREF is also set, then the values with u.x.iOrderByCol>0 -** are simply omitted rather than being copied from srcReg. -*/ -int sqlite3ExprCodeExprList( - Parse *pParse, /* Parsing context */ - ExprList *pList, /* The expression list to be coded */ - int target, /* Where to write results */ - int srcReg, /* Source registers if SQLITE_ECEL_REF */ - u8 flags /* SQLITE_ECEL_* flags */ -){ - struct ExprList_item *pItem; - int i, j, n; - u8 copyOp = (flags & SQLITE_ECEL_DUP) ? OP_Copy : OP_SCopy; - Vdbe *v = pParse->pVdbe; - assert( pList!=0 ); - assert( target>0 ); - assert( pParse->pVdbe!=0 ); /* Never gets this far otherwise */ - n = pList->nExpr; - if( !ConstFactorOk(pParse) ) flags &= ~SQLITE_ECEL_FACTOR; - for(pItem=pList->a, i=0; i<n; i++, pItem++){ - Expr *pExpr = pItem->pExpr; -#ifdef SQLITE_ENABLE_SORTER_REFERENCES - if( pItem->bSorterRef ){ - i--; - n--; - }else -#endif - if( (flags & SQLITE_ECEL_REF)!=0 && (j = pItem->u.x.iOrderByCol)>0 ){ - if( flags & SQLITE_ECEL_OMITREF ){ - i--; - n--; - }else{ - sqlite3VdbeAddOp2(v, copyOp, j+srcReg-1, target+i); - } - }else if( (flags & SQLITE_ECEL_FACTOR)!=0 && sqlite3ExprIsConstant(pExpr) ){ - sqlite3ExprCodeAtInit(pParse, pExpr, target+i); - }else{ - int inReg = sqlite3ExprCodeTarget(pParse, pExpr, target+i); - if( inReg!=target+i ){ - VdbeOp *pOp; - if( copyOp==OP_Copy - && (pOp=sqlite3VdbeGetOp(v, -1))->opcode==OP_Copy - && pOp->p1+pOp->p3+1==inReg - && pOp->p2+pOp->p3+1==target+i - ){ - pOp->p3++; - }else{ - sqlite3VdbeAddOp2(v, copyOp, inReg, target+i); - } - } - } - } - return n; -} - -/* -** Generate code for a BETWEEN operator. -** -** x BETWEEN y AND z -** -** The above is equivalent to -** -** x>=y AND x<=z -** -** Code it as such, taking care to do the common subexpression -** elimination of x. -** -** The xJumpIf parameter determines details: -** -** NULL: Store the boolean result in reg[dest] -** sqlite3ExprIfTrue: Jump to dest if true -** sqlite3ExprIfFalse: Jump to dest if false -** -** The jumpIfNull parameter is ignored if xJumpIf is NULL. -*/ -static void exprCodeBetween( - Parse *pParse, /* Parsing and code generating context */ - Expr *pExpr, /* The BETWEEN expression */ - int dest, /* Jump destination or storage location */ - void (*xJump)(Parse*,Expr*,int,int), /* Action to take */ - int jumpIfNull /* Take the jump if the BETWEEN is NULL */ -){ - Expr exprAnd; /* The AND operator in x>=y AND x<=z */ - Expr compLeft; /* The x>=y term */ - Expr compRight; /* The x<=z term */ - Expr exprX; /* The x subexpression */ - int regFree1 = 0; /* Temporary use register */ - - - memset(&compLeft, 0, sizeof(Expr)); - memset(&compRight, 0, sizeof(Expr)); - memset(&exprAnd, 0, sizeof(Expr)); - - assert( !ExprHasProperty(pExpr, EP_xIsSelect) ); - exprX = *pExpr->pLeft; - exprAnd.op = TK_AND; - exprAnd.pLeft = &compLeft; - exprAnd.pRight = &compRight; - compLeft.op = TK_GE; - compLeft.pLeft = &exprX; - compLeft.pRight = pExpr->x.pList->a[0].pExpr; - compRight.op = TK_LE; - compRight.pLeft = &exprX; - compRight.pRight = pExpr->x.pList->a[1].pExpr; - exprToRegister(&exprX, exprCodeVector(pParse, &exprX, ®Free1)); - if( xJump ){ - xJump(pParse, &exprAnd, dest, jumpIfNull); - }else{ - /* Mark the expression is being from the ON or USING clause of a join - ** so that the sqlite3ExprCodeTarget() routine will not attempt to move - ** it into the Parse.pConstExpr list. We should use a new bit for this, - ** for clarity, but we are out of bits in the Expr.flags field so we - ** have to reuse the EP_FromJoin bit. Bummer. */ - exprX.flags |= EP_FromJoin; - sqlite3ExprCodeTarget(pParse, &exprAnd, dest); - } - sqlite3ReleaseTempReg(pParse, regFree1); - - /* Ensure adequate test coverage */ - testcase( xJump==sqlite3ExprIfTrue && jumpIfNull==0 && regFree1==0 ); - testcase( xJump==sqlite3ExprIfTrue && jumpIfNull==0 && regFree1!=0 ); - testcase( xJump==sqlite3ExprIfTrue && jumpIfNull!=0 && regFree1==0 ); - testcase( xJump==sqlite3ExprIfTrue && jumpIfNull!=0 && regFree1!=0 ); - testcase( xJump==sqlite3ExprIfFalse && jumpIfNull==0 && regFree1==0 ); - testcase( xJump==sqlite3ExprIfFalse && jumpIfNull==0 && regFree1!=0 ); - testcase( xJump==sqlite3ExprIfFalse && jumpIfNull!=0 && regFree1==0 ); - testcase( xJump==sqlite3ExprIfFalse && jumpIfNull!=0 && regFree1!=0 ); - testcase( xJump==0 ); -} - -/* -** Generate code for a boolean expression such that a jump is made -** to the label "dest" if the expression is true but execution -** continues straight thru if the expression is false. -** -** If the expression evaluates to NULL (neither true nor false), then -** take the jump if the jumpIfNull flag is SQLITE_JUMPIFNULL. -** -** This code depends on the fact that certain token values (ex: TK_EQ) -** are the same as opcode values (ex: OP_Eq) that implement the corresponding -** operation. Special comments in vdbe.c and the mkopcodeh.awk script in -** the make process cause these values to align. Assert()s in the code -** below verify that the numbers are aligned correctly. -*/ -void sqlite3ExprIfTrue(Parse *pParse, Expr *pExpr, int dest, int jumpIfNull){ - Vdbe *v = pParse->pVdbe; - int op = 0; - int regFree1 = 0; - int regFree2 = 0; - int r1, r2; - - assert( jumpIfNull==SQLITE_JUMPIFNULL || jumpIfNull==0 ); - if( NEVER(v==0) ) return; /* Existence of VDBE checked by caller */ - if( NEVER(pExpr==0) ) return; /* No way this can happen */ - op = pExpr->op; - switch( op ){ - case TK_AND: { - int d2 = sqlite3VdbeMakeLabel(v); - testcase( jumpIfNull==0 ); - sqlite3ExprIfFalse(pParse, pExpr->pLeft, d2,jumpIfNull^SQLITE_JUMPIFNULL); - sqlite3ExprCachePush(pParse); - sqlite3ExprIfTrue(pParse, pExpr->pRight, dest, jumpIfNull); - sqlite3VdbeResolveLabel(v, d2); - sqlite3ExprCachePop(pParse); - break; - } - case TK_OR: { - testcase( jumpIfNull==0 ); - sqlite3ExprIfTrue(pParse, pExpr->pLeft, dest, jumpIfNull); - sqlite3ExprCachePush(pParse); - sqlite3ExprIfTrue(pParse, pExpr->pRight, dest, jumpIfNull); - sqlite3ExprCachePop(pParse); - break; - } - case TK_NOT: { - testcase( jumpIfNull==0 ); - sqlite3ExprIfFalse(pParse, pExpr->pLeft, dest, jumpIfNull); - break; - } - case TK_TRUTH: { - int isNot; /* IS NOT TRUE or IS NOT FALSE */ - int isTrue; /* IS TRUE or IS NOT TRUE */ - testcase( jumpIfNull==0 ); - isNot = pExpr->op2==TK_ISNOT; - isTrue = sqlite3ExprTruthValue(pExpr->pRight); - testcase( isTrue && isNot ); - testcase( !isTrue && isNot ); - if( isTrue ^ isNot ){ - sqlite3ExprIfTrue(pParse, pExpr->pLeft, dest, - isNot ? SQLITE_JUMPIFNULL : 0); - }else{ - sqlite3ExprIfFalse(pParse, pExpr->pLeft, dest, - isNot ? SQLITE_JUMPIFNULL : 0); - } - break; - } - case TK_IS: - case TK_ISNOT: - testcase( op==TK_IS ); - testcase( op==TK_ISNOT ); - op = (op==TK_IS) ? TK_EQ : TK_NE; - jumpIfNull = SQLITE_NULLEQ; - /* Fall thru */ - case TK_LT: - case TK_LE: - case TK_GT: - case TK_GE: - case TK_NE: - case TK_EQ: { - if( sqlite3ExprIsVector(pExpr->pLeft) ) goto default_expr; - testcase( jumpIfNull==0 ); - r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1); - r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, ®Free2); - codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op, - r1, r2, dest, jumpIfNull); - assert(TK_LT==OP_Lt); testcase(op==OP_Lt); VdbeCoverageIf(v,op==OP_Lt); - assert(TK_LE==OP_Le); testcase(op==OP_Le); VdbeCoverageIf(v,op==OP_Le); - assert(TK_GT==OP_Gt); testcase(op==OP_Gt); VdbeCoverageIf(v,op==OP_Gt); - assert(TK_GE==OP_Ge); testcase(op==OP_Ge); VdbeCoverageIf(v,op==OP_Ge); - assert(TK_EQ==OP_Eq); testcase(op==OP_Eq); - VdbeCoverageIf(v, op==OP_Eq && jumpIfNull==SQLITE_NULLEQ); - VdbeCoverageIf(v, op==OP_Eq && jumpIfNull!=SQLITE_NULLEQ); - assert(TK_NE==OP_Ne); testcase(op==OP_Ne); - VdbeCoverageIf(v, op==OP_Ne && jumpIfNull==SQLITE_NULLEQ); - VdbeCoverageIf(v, op==OP_Ne && jumpIfNull!=SQLITE_NULLEQ); - testcase( regFree1==0 ); - testcase( regFree2==0 ); - break; - } - case TK_ISNULL: - case TK_NOTNULL: { - assert( TK_ISNULL==OP_IsNull ); testcase( op==TK_ISNULL ); - assert( TK_NOTNULL==OP_NotNull ); testcase( op==TK_NOTNULL ); - r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1); - sqlite3VdbeAddOp2(v, op, r1, dest); - VdbeCoverageIf(v, op==TK_ISNULL); - VdbeCoverageIf(v, op==TK_NOTNULL); - testcase( regFree1==0 ); - break; - } - case TK_BETWEEN: { - testcase( jumpIfNull==0 ); - exprCodeBetween(pParse, pExpr, dest, sqlite3ExprIfTrue, jumpIfNull); - break; - } -#ifndef SQLITE_OMIT_SUBQUERY - case TK_IN: { - int destIfFalse = sqlite3VdbeMakeLabel(v); - int destIfNull = jumpIfNull ? dest : destIfFalse; - sqlite3ExprCodeIN(pParse, pExpr, destIfFalse, destIfNull); - sqlite3VdbeGoto(v, dest); - sqlite3VdbeResolveLabel(v, destIfFalse); - break; - } -#endif - default: { - default_expr: - if( exprAlwaysTrue(pExpr) ){ - sqlite3VdbeGoto(v, dest); - }else if( exprAlwaysFalse(pExpr) ){ - /* No-op */ - }else{ - r1 = sqlite3ExprCodeTemp(pParse, pExpr, ®Free1); - sqlite3VdbeAddOp3(v, OP_If, r1, dest, jumpIfNull!=0); - VdbeCoverage(v); - testcase( regFree1==0 ); - testcase( jumpIfNull==0 ); - } - break; - } - } - sqlite3ReleaseTempReg(pParse, regFree1); - sqlite3ReleaseTempReg(pParse, regFree2); -} - -/* -** Generate code for a boolean expression such that a jump is made -** to the label "dest" if the expression is false but execution -** continues straight thru if the expression is true. -** -** If the expression evaluates to NULL (neither true nor false) then -** jump if jumpIfNull is SQLITE_JUMPIFNULL or fall through if jumpIfNull -** is 0. -*/ -void sqlite3ExprIfFalse(Parse *pParse, Expr *pExpr, int dest, int jumpIfNull){ - Vdbe *v = pParse->pVdbe; - int op = 0; - int regFree1 = 0; - int regFree2 = 0; - int r1, r2; - - assert( jumpIfNull==SQLITE_JUMPIFNULL || jumpIfNull==0 ); - if( NEVER(v==0) ) return; /* Existence of VDBE checked by caller */ - if( pExpr==0 ) return; - - /* The value of pExpr->op and op are related as follows: - ** - ** pExpr->op op - ** --------- ---------- - ** TK_ISNULL OP_NotNull - ** TK_NOTNULL OP_IsNull - ** TK_NE OP_Eq - ** TK_EQ OP_Ne - ** TK_GT OP_Le - ** TK_LE OP_Gt - ** TK_GE OP_Lt - ** TK_LT OP_Ge - ** - ** For other values of pExpr->op, op is undefined and unused. - ** The value of TK_ and OP_ constants are arranged such that we - ** can compute the mapping above using the following expression. - ** Assert()s verify that the computation is correct. - */ - op = ((pExpr->op+(TK_ISNULL&1))^1)-(TK_ISNULL&1); - - /* Verify correct alignment of TK_ and OP_ constants - */ - assert( pExpr->op!=TK_ISNULL || op==OP_NotNull ); - assert( pExpr->op!=TK_NOTNULL || op==OP_IsNull ); - assert( pExpr->op!=TK_NE || op==OP_Eq ); - assert( pExpr->op!=TK_EQ || op==OP_Ne ); - assert( pExpr->op!=TK_LT || op==OP_Ge ); - assert( pExpr->op!=TK_LE || op==OP_Gt ); - assert( pExpr->op!=TK_GT || op==OP_Le ); - assert( pExpr->op!=TK_GE || op==OP_Lt ); - - switch( pExpr->op ){ - case TK_AND: { - testcase( jumpIfNull==0 ); - sqlite3ExprIfFalse(pParse, pExpr->pLeft, dest, jumpIfNull); - sqlite3ExprCachePush(pParse); - sqlite3ExprIfFalse(pParse, pExpr->pRight, dest, jumpIfNull); - sqlite3ExprCachePop(pParse); - break; - } - case TK_OR: { - int d2 = sqlite3VdbeMakeLabel(v); - testcase( jumpIfNull==0 ); - sqlite3ExprIfTrue(pParse, pExpr->pLeft, d2, jumpIfNull^SQLITE_JUMPIFNULL); - sqlite3ExprCachePush(pParse); - sqlite3ExprIfFalse(pParse, pExpr->pRight, dest, jumpIfNull); - sqlite3VdbeResolveLabel(v, d2); - sqlite3ExprCachePop(pParse); - break; - } - case TK_NOT: { - testcase( jumpIfNull==0 ); - sqlite3ExprIfTrue(pParse, pExpr->pLeft, dest, jumpIfNull); - break; - } - case TK_TRUTH: { - int isNot; /* IS NOT TRUE or IS NOT FALSE */ - int isTrue; /* IS TRUE or IS NOT TRUE */ - testcase( jumpIfNull==0 ); - isNot = pExpr->op2==TK_ISNOT; - isTrue = sqlite3ExprTruthValue(pExpr->pRight); - testcase( isTrue && isNot ); - testcase( !isTrue && isNot ); - if( isTrue ^ isNot ){ - /* IS TRUE and IS NOT FALSE */ - sqlite3ExprIfFalse(pParse, pExpr->pLeft, dest, - isNot ? 0 : SQLITE_JUMPIFNULL); - - }else{ - /* IS FALSE and IS NOT TRUE */ - sqlite3ExprIfTrue(pParse, pExpr->pLeft, dest, - isNot ? 0 : SQLITE_JUMPIFNULL); - } - break; - } - case TK_IS: - case TK_ISNOT: - testcase( pExpr->op==TK_IS ); - testcase( pExpr->op==TK_ISNOT ); - op = (pExpr->op==TK_IS) ? TK_NE : TK_EQ; - jumpIfNull = SQLITE_NULLEQ; - /* Fall thru */ - case TK_LT: - case TK_LE: - case TK_GT: - case TK_GE: - case TK_NE: - case TK_EQ: { - if( sqlite3ExprIsVector(pExpr->pLeft) ) goto default_expr; - testcase( jumpIfNull==0 ); - r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1); - r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, ®Free2); - codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op, - r1, r2, dest, jumpIfNull); - assert(TK_LT==OP_Lt); testcase(op==OP_Lt); VdbeCoverageIf(v,op==OP_Lt); - assert(TK_LE==OP_Le); testcase(op==OP_Le); VdbeCoverageIf(v,op==OP_Le); - assert(TK_GT==OP_Gt); testcase(op==OP_Gt); VdbeCoverageIf(v,op==OP_Gt); - assert(TK_GE==OP_Ge); testcase(op==OP_Ge); VdbeCoverageIf(v,op==OP_Ge); - assert(TK_EQ==OP_Eq); testcase(op==OP_Eq); - VdbeCoverageIf(v, op==OP_Eq && jumpIfNull!=SQLITE_NULLEQ); - VdbeCoverageIf(v, op==OP_Eq && jumpIfNull==SQLITE_NULLEQ); - assert(TK_NE==OP_Ne); testcase(op==OP_Ne); - VdbeCoverageIf(v, op==OP_Ne && jumpIfNull!=SQLITE_NULLEQ); - VdbeCoverageIf(v, op==OP_Ne && jumpIfNull==SQLITE_NULLEQ); - testcase( regFree1==0 ); - testcase( regFree2==0 ); - break; - } - case TK_ISNULL: - case TK_NOTNULL: { - r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1); - sqlite3VdbeAddOp2(v, op, r1, dest); - testcase( op==TK_ISNULL ); VdbeCoverageIf(v, op==TK_ISNULL); - testcase( op==TK_NOTNULL ); VdbeCoverageIf(v, op==TK_NOTNULL); - testcase( regFree1==0 ); - break; - } - case TK_BETWEEN: { - testcase( jumpIfNull==0 ); - exprCodeBetween(pParse, pExpr, dest, sqlite3ExprIfFalse, jumpIfNull); - break; - } -#ifndef SQLITE_OMIT_SUBQUERY - case TK_IN: { - if( jumpIfNull ){ - sqlite3ExprCodeIN(pParse, pExpr, dest, dest); - }else{ - int destIfNull = sqlite3VdbeMakeLabel(v); - sqlite3ExprCodeIN(pParse, pExpr, dest, destIfNull); - sqlite3VdbeResolveLabel(v, destIfNull); - } - break; - } -#endif - default: { - default_expr: - if( exprAlwaysFalse(pExpr) ){ - sqlite3VdbeGoto(v, dest); - }else if( exprAlwaysTrue(pExpr) ){ - /* no-op */ - }else{ - r1 = sqlite3ExprCodeTemp(pParse, pExpr, ®Free1); - sqlite3VdbeAddOp3(v, OP_IfNot, r1, dest, jumpIfNull!=0); - VdbeCoverage(v); - testcase( regFree1==0 ); - testcase( jumpIfNull==0 ); - } - break; - } - } - sqlite3ReleaseTempReg(pParse, regFree1); - sqlite3ReleaseTempReg(pParse, regFree2); -} - -/* -** Like sqlite3ExprIfFalse() except that a copy is made of pExpr before -** code generation, and that copy is deleted after code generation. This -** ensures that the original pExpr is unchanged. -*/ -void sqlite3ExprIfFalseDup(Parse *pParse, Expr *pExpr, int dest,int jumpIfNull){ - sqlite3 *db = pParse->db; - Expr *pCopy = sqlite3ExprDup(db, pExpr, 0); - if( db->mallocFailed==0 ){ - sqlite3ExprIfFalse(pParse, pCopy, dest, jumpIfNull); - } - sqlite3ExprDelete(db, pCopy); -} - -/* -** Expression pVar is guaranteed to be an SQL variable. pExpr may be any -** type of expression. -** -** If pExpr is a simple SQL value - an integer, real, string, blob -** or NULL value - then the VDBE currently being prepared is configured -** to re-prepare each time a new value is bound to variable pVar. -** -** Additionally, if pExpr is a simple SQL value and the value is the -** same as that currently bound to variable pVar, non-zero is returned. -** Otherwise, if the values are not the same or if pExpr is not a simple -** SQL value, zero is returned. -*/ -static int exprCompareVariable(Parse *pParse, Expr *pVar, Expr *pExpr){ - int res = 0; - int iVar; - sqlite3_value *pL, *pR = 0; - - sqlite3ValueFromExpr(pParse->db, pExpr, SQLITE_UTF8, SQLITE_AFF_BLOB, &pR); - if( pR ){ - iVar = pVar->iColumn; - sqlite3VdbeSetVarmask(pParse->pVdbe, iVar); - pL = sqlite3VdbeGetBoundValue(pParse->pReprepare, iVar, SQLITE_AFF_BLOB); - if( pL ){ - if( sqlite3_value_type(pL)==SQLITE_TEXT ){ - sqlite3_value_text(pL); /* Make sure the encoding is UTF-8 */ - } - res = 0==sqlite3MemCompare(pL, pR, 0); - } - sqlite3ValueFree(pR); - sqlite3ValueFree(pL); - } - - return res; -} - -/* -** Do a deep comparison of two expression trees. Return 0 if the two -** expressions are completely identical. Return 1 if they differ only -** by a COLLATE operator at the top level. Return 2 if there are differences -** other than the top-level COLLATE operator. -** -** If any subelement of pB has Expr.iTable==(-1) then it is allowed -** to compare equal to an equivalent element in pA with Expr.iTable==iTab. -** -** The pA side might be using TK_REGISTER. If that is the case and pB is -** not using TK_REGISTER but is otherwise equivalent, then still return 0. -** -** Sometimes this routine will return 2 even if the two expressions -** really are equivalent. If we cannot prove that the expressions are -** identical, we return 2 just to be safe. So if this routine -** returns 2, then you do not really know for certain if the two -** expressions are the same. But if you get a 0 or 1 return, then you -** can be sure the expressions are the same. In the places where -** this routine is used, it does not hurt to get an extra 2 - that -** just might result in some slightly slower code. But returning -** an incorrect 0 or 1 could lead to a malfunction. -** -** If pParse is not NULL then TK_VARIABLE terms in pA with bindings in -** pParse->pReprepare can be matched against literals in pB. The -** pParse->pVdbe->expmask bitmask is updated for each variable referenced. -** If pParse is NULL (the normal case) then any TK_VARIABLE term in -** Argument pParse should normally be NULL. If it is not NULL and pA or -** pB causes a return value of 2. -*/ -int sqlite3ExprCompare(Parse *pParse, Expr *pA, Expr *pB, int iTab){ - u32 combinedFlags; - if( pA==0 || pB==0 ){ - return pB==pA ? 0 : 2; - } - if( pParse && pA->op==TK_VARIABLE && exprCompareVariable(pParse, pA, pB) ){ - return 0; - } - combinedFlags = pA->flags | pB->flags; - if( combinedFlags & EP_IntValue ){ - if( (pA->flags&pB->flags&EP_IntValue)!=0 && pA->u.iValue==pB->u.iValue ){ - return 0; - } - return 2; - } - if( pA->op!=pB->op ){ - if( pA->op==TK_COLLATE && sqlite3ExprCompare(pParse, pA->pLeft,pB,iTab)<2 ){ - return 1; - } - if( pB->op==TK_COLLATE && sqlite3ExprCompare(pParse, pA,pB->pLeft,iTab)<2 ){ - return 1; - } - return 2; - } - if( pA->op!=TK_COLUMN && pA->op!=TK_AGG_COLUMN && pA->u.zToken ){ - if( pA->op==TK_FUNCTION ){ - if( sqlite3StrICmp(pA->u.zToken,pB->u.zToken)!=0 ) return 2; - }else if( pA->op==TK_COLLATE ){ - if( sqlite3_stricmp(pA->u.zToken,pB->u.zToken)!=0 ) return 2; - }else if( strcmp(pA->u.zToken,pB->u.zToken)!=0 ){ - return 2; - } - } - if( (pA->flags & EP_Distinct)!=(pB->flags & EP_Distinct) ) return 2; - if( ALWAYS((combinedFlags & EP_TokenOnly)==0) ){ - if( combinedFlags & EP_xIsSelect ) return 2; - if( sqlite3ExprCompare(pParse, pA->pLeft, pB->pLeft, iTab) ) return 2; - if( sqlite3ExprCompare(pParse, pA->pRight, pB->pRight, iTab) ) return 2; - if( sqlite3ExprListCompare(pA->x.pList, pB->x.pList, iTab) ) return 2; - assert( (combinedFlags & EP_Reduced)==0 ); - if( pA->op!=TK_STRING && pA->op!=TK_TRUEFALSE ){ - if( pA->iColumn!=pB->iColumn ) return 2; - if( pA->iTable!=pB->iTable - && (pA->iTable!=iTab || NEVER(pB->iTable>=0)) ) return 2; - } - } - return 0; -} - -/* -** Compare two ExprList objects. Return 0 if they are identical and -** non-zero if they differ in any way. -** -** If any subelement of pB has Expr.iTable==(-1) then it is allowed -** to compare equal to an equivalent element in pA with Expr.iTable==iTab. -** -** This routine might return non-zero for equivalent ExprLists. The -** only consequence will be disabled optimizations. But this routine -** must never return 0 if the two ExprList objects are different, or -** a malfunction will result. -** -** Two NULL pointers are considered to be the same. But a NULL pointer -** always differs from a non-NULL pointer. -*/ -int sqlite3ExprListCompare(ExprList *pA, ExprList *pB, int iTab){ - int i; - if( pA==0 && pB==0 ) return 0; - if( pA==0 || pB==0 ) return 1; - if( pA->nExpr!=pB->nExpr ) return 1; - for(i=0; i<pA->nExpr; i++){ - Expr *pExprA = pA->a[i].pExpr; - Expr *pExprB = pB->a[i].pExpr; - if( pA->a[i].sortOrder!=pB->a[i].sortOrder ) return 1; - if( sqlite3ExprCompare(0, pExprA, pExprB, iTab) ) return 1; - } - return 0; -} - -/* -** Like sqlite3ExprCompare() except COLLATE operators at the top-level -** are ignored. -*/ -int sqlite3ExprCompareSkip(Expr *pA, Expr *pB, int iTab){ - return sqlite3ExprCompare(0, - sqlite3ExprSkipCollate(pA), - sqlite3ExprSkipCollate(pB), - iTab); -} - -/* -** Return true if we can prove the pE2 will always be true if pE1 is -** true. Return false if we cannot complete the proof or if pE2 might -** be false. Examples: -** -** pE1: x==5 pE2: x==5 Result: true -** pE1: x>0 pE2: x==5 Result: false -** pE1: x=21 pE2: x=21 OR y=43 Result: true -** pE1: x!=123 pE2: x IS NOT NULL Result: true -** pE1: x!=?1 pE2: x IS NOT NULL Result: true -** pE1: x IS NULL pE2: x IS NOT NULL Result: false -** pE1: x IS ?2 pE2: x IS NOT NULL Reuslt: false -** -** When comparing TK_COLUMN nodes between pE1 and pE2, if pE2 has -** Expr.iTable<0 then assume a table number given by iTab. -** -** If pParse is not NULL, then the values of bound variables in pE1 are -** compared against literal values in pE2 and pParse->pVdbe->expmask is -** modified to record which bound variables are referenced. If pParse -** is NULL, then false will be returned if pE1 contains any bound variables. -** -** When in doubt, return false. Returning true might give a performance -** improvement. Returning false might cause a performance reduction, but -** it will always give the correct answer and is hence always safe. -*/ -int sqlite3ExprImpliesExpr(Parse *pParse, Expr *pE1, Expr *pE2, int iTab){ - if( sqlite3ExprCompare(pParse, pE1, pE2, iTab)==0 ){ - return 1; - } - if( pE2->op==TK_OR - && (sqlite3ExprImpliesExpr(pParse, pE1, pE2->pLeft, iTab) - || sqlite3ExprImpliesExpr(pParse, pE1, pE2->pRight, iTab) ) - ){ - return 1; - } - if( pE2->op==TK_NOTNULL && pE1->op!=TK_ISNULL && pE1->op!=TK_IS ){ - Expr *pX = sqlite3ExprSkipCollate(pE1->pLeft); - testcase( pX!=pE1->pLeft ); - if( sqlite3ExprCompare(pParse, pX, pE2->pLeft, iTab)==0 ) return 1; - } - return 0; -} - -/* -** This is the Expr node callback for sqlite3ExprImpliesNotNullRow(). -** If the expression node requires that the table at pWalker->iCur -** have a non-NULL column, then set pWalker->eCode to 1 and abort. -*/ -static int impliesNotNullRow(Walker *pWalker, Expr *pExpr){ - /* This routine is only called for WHERE clause expressions and so it - ** cannot have any TK_AGG_COLUMN entries because those are only found - ** in HAVING clauses. We can get a TK_AGG_FUNCTION in a WHERE clause, - ** but that is an illegal construct and the query will be rejected at - ** a later stage of processing, so the TK_AGG_FUNCTION case does not - ** need to be considered here. */ - assert( pExpr->op!=TK_AGG_COLUMN ); - testcase( pExpr->op==TK_AGG_FUNCTION ); - - if( ExprHasProperty(pExpr, EP_FromJoin) ) return WRC_Prune; - switch( pExpr->op ){ - case TK_ISNOT: - case TK_NOT: - case TK_ISNULL: - case TK_IS: - case TK_OR: - case TK_CASE: - case TK_IN: - case TK_FUNCTION: - testcase( pExpr->op==TK_ISNOT ); - testcase( pExpr->op==TK_NOT ); - testcase( pExpr->op==TK_ISNULL ); - testcase( pExpr->op==TK_IS ); - testcase( pExpr->op==TK_OR ); - testcase( pExpr->op==TK_CASE ); - testcase( pExpr->op==TK_IN ); - testcase( pExpr->op==TK_FUNCTION ); - return WRC_Prune; - case TK_COLUMN: - if( pWalker->u.iCur==pExpr->iTable ){ - pWalker->eCode = 1; - return WRC_Abort; - } - return WRC_Prune; - - /* Virtual tables are allowed to use constraints like x=NULL. So - ** a term of the form x=y does not prove that y is not null if x - ** is the column of a virtual table */ - case TK_EQ: - case TK_NE: - case TK_LT: - case TK_LE: - case TK_GT: - case TK_GE: - testcase( pExpr->op==TK_EQ ); - testcase( pExpr->op==TK_NE ); - testcase( pExpr->op==TK_LT ); - testcase( pExpr->op==TK_LE ); - testcase( pExpr->op==TK_GT ); - testcase( pExpr->op==TK_GE ); - if( (pExpr->pLeft->op==TK_COLUMN && IsVirtual(pExpr->pLeft->pTab)) - || (pExpr->pRight->op==TK_COLUMN && IsVirtual(pExpr->pRight->pTab)) - ){ - return WRC_Prune; - } - default: - return WRC_Continue; - } -} - -/* -** Return true (non-zero) if expression p can only be true if at least -** one column of table iTab is non-null. In other words, return true -** if expression p will always be NULL or false if every column of iTab -** is NULL. -** -** False negatives are acceptable. In other words, it is ok to return -** zero even if expression p will never be true of every column of iTab -** is NULL. A false negative is merely a missed optimization opportunity. -** -** False positives are not allowed, however. A false positive may result -** in an incorrect answer. -** -** Terms of p that are marked with EP_FromJoin (and hence that come from -** the ON or USING clauses of LEFT JOINS) are excluded from the analysis. -** -** This routine is used to check if a LEFT JOIN can be converted into -** an ordinary JOIN. The p argument is the WHERE clause. If the WHERE -** clause requires that some column of the right table of the LEFT JOIN -** be non-NULL, then the LEFT JOIN can be safely converted into an -** ordinary join. -*/ -int sqlite3ExprImpliesNonNullRow(Expr *p, int iTab){ - Walker w; - w.xExprCallback = impliesNotNullRow; - w.xSelectCallback = 0; - w.xSelectCallback2 = 0; - w.eCode = 0; - w.u.iCur = iTab; - sqlite3WalkExpr(&w, p); - return w.eCode; -} - -/* -** An instance of the following structure is used by the tree walker -** to determine if an expression can be evaluated by reference to the -** index only, without having to do a search for the corresponding -** table entry. The IdxCover.pIdx field is the index. IdxCover.iCur -** is the cursor for the table. -*/ -struct IdxCover { - Index *pIdx; /* The index to be tested for coverage */ - int iCur; /* Cursor number for the table corresponding to the index */ -}; - -/* -** Check to see if there are references to columns in table -** pWalker->u.pIdxCover->iCur can be satisfied using the index -** pWalker->u.pIdxCover->pIdx. -*/ -static int exprIdxCover(Walker *pWalker, Expr *pExpr){ - if( pExpr->op==TK_COLUMN - && pExpr->iTable==pWalker->u.pIdxCover->iCur - && sqlite3ColumnOfIndex(pWalker->u.pIdxCover->pIdx, pExpr->iColumn)<0 - ){ - pWalker->eCode = 1; - return WRC_Abort; - } - return WRC_Continue; -} - -/* -** Determine if an index pIdx on table with cursor iCur contains will -** the expression pExpr. Return true if the index does cover the -** expression and false if the pExpr expression references table columns -** that are not found in the index pIdx. -** -** An index covering an expression means that the expression can be -** evaluated using only the index and without having to lookup the -** corresponding table entry. -*/ -int sqlite3ExprCoveredByIndex( - Expr *pExpr, /* The index to be tested */ - int iCur, /* The cursor number for the corresponding table */ - Index *pIdx /* The index that might be used for coverage */ -){ - Walker w; - struct IdxCover xcov; - memset(&w, 0, sizeof(w)); - xcov.iCur = iCur; - xcov.pIdx = pIdx; - w.xExprCallback = exprIdxCover; - w.u.pIdxCover = &xcov; - sqlite3WalkExpr(&w, pExpr); - return !w.eCode; -} - - -/* -** An instance of the following structure is used by the tree walker -** to count references to table columns in the arguments of an -** aggregate function, in order to implement the -** sqlite3FunctionThisSrc() routine. -*/ -struct SrcCount { - SrcList *pSrc; /* One particular FROM clause in a nested query */ - int nThis; /* Number of references to columns in pSrcList */ - int nOther; /* Number of references to columns in other FROM clauses */ -}; - -/* -** Count the number of references to columns. -*/ -static int exprSrcCount(Walker *pWalker, Expr *pExpr){ - /* The NEVER() on the second term is because sqlite3FunctionUsesThisSrc() - ** is always called before sqlite3ExprAnalyzeAggregates() and so the - ** TK_COLUMNs have not yet been converted into TK_AGG_COLUMN. If - ** sqlite3FunctionUsesThisSrc() is used differently in the future, the - ** NEVER() will need to be removed. */ - if( pExpr->op==TK_COLUMN || NEVER(pExpr->op==TK_AGG_COLUMN) ){ - int i; - struct SrcCount *p = pWalker->u.pSrcCount; - SrcList *pSrc = p->pSrc; - int nSrc = pSrc ? pSrc->nSrc : 0; - for(i=0; i<nSrc; i++){ - if( pExpr->iTable==pSrc->a[i].iCursor ) break; - } - if( i<nSrc ){ - p->nThis++; - }else{ - p->nOther++; - } - } - return WRC_Continue; -} - -/* -** Determine if any of the arguments to the pExpr Function reference -** pSrcList. Return true if they do. Also return true if the function -** has no arguments or has only constant arguments. Return false if pExpr -** references columns but not columns of tables found in pSrcList. -*/ -int sqlite3FunctionUsesThisSrc(Expr *pExpr, SrcList *pSrcList){ - Walker w; - struct SrcCount cnt; - assert( pExpr->op==TK_AGG_FUNCTION ); - w.xExprCallback = exprSrcCount; - w.xSelectCallback = 0; - w.u.pSrcCount = &cnt; - cnt.pSrc = pSrcList; - cnt.nThis = 0; - cnt.nOther = 0; - sqlite3WalkExprList(&w, pExpr->x.pList); - return cnt.nThis>0 || cnt.nOther==0; -} - -/* -** Add a new element to the pAggInfo->aCol[] array. Return the index of -** the new element. Return a negative number if malloc fails. -*/ -static int addAggInfoColumn(sqlite3 *db, AggInfo *pInfo){ - int i; - pInfo->aCol = sqlite3ArrayAllocate( - db, - pInfo->aCol, - sizeof(pInfo->aCol[0]), - &pInfo->nColumn, - &i - ); - return i; -} - -/* -** Add a new element to the pAggInfo->aFunc[] array. Return the index of -** the new element. Return a negative number if malloc fails. -*/ -static int addAggInfoFunc(sqlite3 *db, AggInfo *pInfo){ - int i; - pInfo->aFunc = sqlite3ArrayAllocate( - db, - pInfo->aFunc, - sizeof(pInfo->aFunc[0]), - &pInfo->nFunc, - &i - ); - return i; -} - -/* -** This is the xExprCallback for a tree walker. It is used to -** implement sqlite3ExprAnalyzeAggregates(). See sqlite3ExprAnalyzeAggregates -** for additional information. -*/ -static int analyzeAggregate(Walker *pWalker, Expr *pExpr){ - int i; - NameContext *pNC = pWalker->u.pNC; - Parse *pParse = pNC->pParse; - SrcList *pSrcList = pNC->pSrcList; - AggInfo *pAggInfo = pNC->uNC.pAggInfo; - - assert( pNC->ncFlags & NC_UAggInfo ); - switch( pExpr->op ){ - case TK_AGG_COLUMN: - case TK_COLUMN: { - testcase( pExpr->op==TK_AGG_COLUMN ); - testcase( pExpr->op==TK_COLUMN ); - /* Check to see if the column is in one of the tables in the FROM - ** clause of the aggregate query */ - if( ALWAYS(pSrcList!=0) ){ - struct SrcList_item *pItem = pSrcList->a; - for(i=0; i<pSrcList->nSrc; i++, pItem++){ - struct AggInfo_col *pCol; - assert( !ExprHasProperty(pExpr, EP_TokenOnly|EP_Reduced) ); - if( pExpr->iTable==pItem->iCursor ){ - /* If we reach this point, it means that pExpr refers to a table - ** that is in the FROM clause of the aggregate query. - ** - ** Make an entry for the column in pAggInfo->aCol[] if there - ** is not an entry there already. - */ - int k; - pCol = pAggInfo->aCol; - for(k=0; k<pAggInfo->nColumn; k++, pCol++){ - if( pCol->iTable==pExpr->iTable && - pCol->iColumn==pExpr->iColumn ){ - break; - } - } - if( (k>=pAggInfo->nColumn) - && (k = addAggInfoColumn(pParse->db, pAggInfo))>=0 - ){ - pCol = &pAggInfo->aCol[k]; - pCol->pTab = pExpr->pTab; - pCol->iTable = pExpr->iTable; - pCol->iColumn = pExpr->iColumn; - pCol->iMem = ++pParse->nMem; - pCol->iSorterColumn = -1; - pCol->pExpr = pExpr; - if( pAggInfo->pGroupBy ){ - int j, n; - ExprList *pGB = pAggInfo->pGroupBy; - struct ExprList_item *pTerm = pGB->a; - n = pGB->nExpr; - for(j=0; j<n; j++, pTerm++){ - Expr *pE = pTerm->pExpr; - if( pE->op==TK_COLUMN && pE->iTable==pExpr->iTable && - pE->iColumn==pExpr->iColumn ){ - pCol->iSorterColumn = j; - break; - } - } - } - if( pCol->iSorterColumn<0 ){ - pCol->iSorterColumn = pAggInfo->nSortingColumn++; - } - } - /* There is now an entry for pExpr in pAggInfo->aCol[] (either - ** because it was there before or because we just created it). - ** Convert the pExpr to be a TK_AGG_COLUMN referring to that - ** pAggInfo->aCol[] entry. - */ - ExprSetVVAProperty(pExpr, EP_NoReduce); - pExpr->pAggInfo = pAggInfo; - pExpr->op = TK_AGG_COLUMN; - pExpr->iAgg = (i16)k; - break; - } /* endif pExpr->iTable==pItem->iCursor */ - } /* end loop over pSrcList */ - } - return WRC_Prune; - } - case TK_AGG_FUNCTION: { - if( (pNC->ncFlags & NC_InAggFunc)==0 - && pWalker->walkerDepth==pExpr->op2 - ){ - /* Check to see if pExpr is a duplicate of another aggregate - ** function that is already in the pAggInfo structure - */ - struct AggInfo_func *pItem = pAggInfo->aFunc; - for(i=0; i<pAggInfo->nFunc; i++, pItem++){ - if( sqlite3ExprCompare(0, pItem->pExpr, pExpr, -1)==0 ){ - break; - } - } - if( i>=pAggInfo->nFunc ){ - /* pExpr is original. Make a new entry in pAggInfo->aFunc[] - */ - u8 enc = ENC(pParse->db); - i = addAggInfoFunc(pParse->db, pAggInfo); - if( i>=0 ){ - assert( !ExprHasProperty(pExpr, EP_xIsSelect) ); - pItem = &pAggInfo->aFunc[i]; - pItem->pExpr = pExpr; - pItem->iMem = ++pParse->nMem; - assert( !ExprHasProperty(pExpr, EP_IntValue) ); - pItem->pFunc = sqlite3FindFunction(pParse->db, - pExpr->u.zToken, - pExpr->x.pList ? pExpr->x.pList->nExpr : 0, enc, 0); - if( pExpr->flags & EP_Distinct ){ - pItem->iDistinct = pParse->nTab++; - }else{ - pItem->iDistinct = -1; - } - } - } - /* Make pExpr point to the appropriate pAggInfo->aFunc[] entry - */ - assert( !ExprHasProperty(pExpr, EP_TokenOnly|EP_Reduced) ); - ExprSetVVAProperty(pExpr, EP_NoReduce); - pExpr->iAgg = (i16)i; - pExpr->pAggInfo = pAggInfo; - return WRC_Prune; - }else{ - return WRC_Continue; - } - } - } - return WRC_Continue; -} -static int analyzeAggregatesInSelect(Walker *pWalker, Select *pSelect){ - UNUSED_PARAMETER(pSelect); - pWalker->walkerDepth++; - return WRC_Continue; -} -static void analyzeAggregatesInSelectEnd(Walker *pWalker, Select *pSelect){ - UNUSED_PARAMETER(pSelect); - pWalker->walkerDepth--; -} - -/* -** Analyze the pExpr expression looking for aggregate functions and -** for variables that need to be added to AggInfo object that pNC->pAggInfo -** points to. Additional entries are made on the AggInfo object as -** necessary. -** -** This routine should only be called after the expression has been -** analyzed by sqlite3ResolveExprNames(). -*/ -void sqlite3ExprAnalyzeAggregates(NameContext *pNC, Expr *pExpr){ - Walker w; - w.xExprCallback = analyzeAggregate; - w.xSelectCallback = analyzeAggregatesInSelect; - w.xSelectCallback2 = analyzeAggregatesInSelectEnd; - w.walkerDepth = 0; - w.u.pNC = pNC; - assert( pNC->pSrcList!=0 ); - sqlite3WalkExpr(&w, pExpr); -} - -/* -** Call sqlite3ExprAnalyzeAggregates() for every expression in an -** expression list. Return the number of errors. -** -** If an error is found, the analysis is cut short. -*/ -void sqlite3ExprAnalyzeAggList(NameContext *pNC, ExprList *pList){ - struct ExprList_item *pItem; - int i; - if( pList ){ - for(pItem=pList->a, i=0; i<pList->nExpr; i++, pItem++){ - sqlite3ExprAnalyzeAggregates(pNC, pItem->pExpr); - } - } -} - -/* -** Allocate a single new register for use to hold some intermediate result. -*/ -int sqlite3GetTempReg(Parse *pParse){ - if( pParse->nTempReg==0 ){ - return ++pParse->nMem; - } - return pParse->aTempReg[--pParse->nTempReg]; -} - -/* -** Deallocate a register, making available for reuse for some other -** purpose. -** -** If a register is currently being used by the column cache, then -** the deallocation is deferred until the column cache line that uses -** the register becomes stale. -*/ -void sqlite3ReleaseTempReg(Parse *pParse, int iReg){ - if( iReg && pParse->nTempReg<ArraySize(pParse->aTempReg) ){ - int i; - struct yColCache *p; - for(i=0, p=pParse->aColCache; i<pParse->nColCache; i++, p++){ - if( p->iReg==iReg ){ - p->tempReg = 1; - return; - } - } - pParse->aTempReg[pParse->nTempReg++] = iReg; - } -} - -/* -** Allocate or deallocate a block of nReg consecutive registers. -*/ -int sqlite3GetTempRange(Parse *pParse, int nReg){ - int i, n; - if( nReg==1 ) return sqlite3GetTempReg(pParse); - i = pParse->iRangeReg; - n = pParse->nRangeReg; - if( nReg<=n ){ - assert( !usedAsColumnCache(pParse, i, i+n-1) ); - pParse->iRangeReg += nReg; - pParse->nRangeReg -= nReg; - }else{ - i = pParse->nMem+1; - pParse->nMem += nReg; - } - return i; -} -void sqlite3ReleaseTempRange(Parse *pParse, int iReg, int nReg){ - if( nReg==1 ){ - sqlite3ReleaseTempReg(pParse, iReg); - return; - } - sqlite3ExprCacheRemove(pParse, iReg, nReg); - if( nReg>pParse->nRangeReg ){ - pParse->nRangeReg = nReg; - pParse->iRangeReg = iReg; - } -} - -/* -** Mark all temporary registers as being unavailable for reuse. -*/ -void sqlite3ClearTempRegCache(Parse *pParse){ - pParse->nTempReg = 0; - pParse->nRangeReg = 0; -} - -/* -** Validate that no temporary register falls within the range of -** iFirst..iLast, inclusive. This routine is only call from within assert() -** statements. -*/ -#ifdef SQLITE_DEBUG -int sqlite3NoTempsInRange(Parse *pParse, int iFirst, int iLast){ - int i; - if( pParse->nRangeReg>0 - && pParse->iRangeReg+pParse->nRangeReg > iFirst - && pParse->iRangeReg <= iLast - ){ - return 0; - } - for(i=0; i<pParse->nTempReg; i++){ - if( pParse->aTempReg[i]>=iFirst && pParse->aTempReg[i]<=iLast ){ - return 0; - } - } - return 1; -} -#endif /* SQLITE_DEBUG */ |