/*
** 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.
**
** $Id: expr.c,v 1.399 2008/10/11 16:47:36 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>
/*
** 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 expresssions 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->op;
if( op==TK_SELECT ){
return sqlite3ExprAffinity(pExpr->pSelect->pEList->a[0].pExpr);
}
#ifndef SQLITE_OMIT_CAST
if( op==TK_CAST ){
return sqlite3AffinityType(&pExpr->token);
}
#endif
if( (op==TK_COLUMN || op==TK_REGISTER) && pExpr->pTab!=0 ){
/* op==TK_REGISTER && pExpr->pTab!=0 happens when pExpr was originally
** a TK_COLUMN but was previously evaluated and cached in a register */
int j = pExpr->iColumn;
if( j<0 ) return SQLITE_AFF_INTEGER;
assert( pExpr->pTab && j<pExpr->pTab->nCol );
return pExpr->pTab->aCol[j].affinity;
}
return pExpr->affinity;
}
/*
** Set the collating sequence for expression pExpr to be the collating
** sequence named by pToken. Return a pointer to the revised expression.
** The collating sequence is marked as "explicit" using the EP_ExpCollate
** flag. An explicit collating sequence will override implicit
** collating sequences.
*/
Expr *sqlite3ExprSetColl(Parse *pParse, Expr *pExpr, Token *pCollName){
char *zColl = 0; /* Dequoted name of collation sequence */
CollSeq *pColl;
sqlite3 *db = pParse->db;
zColl = sqlite3NameFromToken(db, pCollName);
if( pExpr && zColl ){
pColl = sqlite3LocateCollSeq(pParse, zColl, -1);
if( pColl ){
pExpr->pColl = pColl;
pExpr->flags |= EP_ExpCollate;
}
}
sqlite3DbFree(db, zColl);
return pExpr;
}
/*
** Return the default collation sequence for the expression pExpr. If
** there is no default collation type, return 0.
*/
CollSeq *sqlite3ExprCollSeq(Parse *pParse, Expr *pExpr){
CollSeq *pColl = 0;
Expr *p = pExpr;
while( p ){
int op;
pColl = p->pColl;
if( pColl ) break;
op = p->op;
if( (op==TK_COLUMN || op==TK_REGISTER) && 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 */
const char *zColl;
int j = p->iColumn;
if( j>=0 ){
sqlite3 *db = pParse->db;
zColl = p->pTab->aCol[j].zColl;
pColl = sqlite3FindCollSeq(db, ENC(db), zColl, -1, 0);
pExpr->pColl = pColl;
}
break;
}
if( op!=TK_CAST && op!=TK_UPLUS ){
break;
}
p = p->pLeft;
}
if( sqlite3CheckCollSeq(pParse, pColl) ){
pColl = 0;
}
return pColl;
}
/*
** 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_NONE;
}
}else if( !aff1 && !aff2 ){
/* Neither side of the comparison is a column. Compare the
** results directly.
*/
return SQLITE_AFF_NONE;
}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 );
assert( pExpr->pLeft );
aff = sqlite3ExprAffinity(pExpr->pLeft);
if( pExpr->pRight ){
aff = sqlite3CompareAffinity(pExpr->pRight, aff);
}
else if( pExpr->pSelect ){
aff = sqlite3CompareAffinity(pExpr->pSelect->pEList->a[0].pExpr, aff);
}
else if( !aff ){
aff = SQLITE_AFF_NONE;
}
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_NONE:
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 = sqlite3CompareAffinity(pExpr1, aff) | 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_ExpCollate ){
assert( pLeft->pColl );
pColl = pLeft->pColl;
}else if( pRight && pRight->flags & EP_ExpCollate ){
assert( pRight->pColl );
pColl = pRight->pColl;
}else{
pColl = sqlite3ExprCollSeq(pParse, pLeft);
if( !pColl ){
pColl = sqlite3ExprCollSeq(pParse, pRight);
}
}
return pColl;
}
/*
** Generate the operands for a comparison operation. Before
** generating the code for each operand, set the EP_AnyAff
** flag on the expression so that it will be able to used a
** cached column value that has previously undergone an
** affinity change.
*/
static void codeCompareOperands(
Parse *pParse, /* Parsing and code generating context */
Expr *pLeft, /* The left operand */
int *pRegLeft, /* Register where left operand is stored */
int *pFreeLeft, /* Free this register when done */
Expr *pRight, /* The right operand */
int *pRegRight, /* Register where right operand is stored */
int *pFreeRight /* Write temp register for right operand there */
){
while( pLeft->op==TK_UPLUS ) pLeft = pLeft->pLeft;
pLeft->flags |= EP_AnyAff;
*pRegLeft = sqlite3ExprCodeTemp(pParse, pLeft, pFreeLeft);
while( pRight->op==TK_UPLUS ) pRight = pRight->pLeft;
pRight->flags |= EP_AnyAff;
*pRegRight = sqlite3ExprCodeTemp(pParse, pRight, pFreeRight);
}
/*
** 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, p5);
if( (p5 & SQLITE_AFF_MASK)!=SQLITE_AFF_NONE ){
sqlite3ExprCacheAffinityChange(pParse, in1, 1);
sqlite3ExprCacheAffinityChange(pParse, in2, 1);
}
return addr;
}
#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 *p, int *pnHeight){
if( p ){
heightOfExpr(p->pWhere, pnHeight);
heightOfExpr(p->pHaving, pnHeight);
heightOfExpr(p->pLimit, pnHeight);
heightOfExpr(p->pOffset, pnHeight);
heightOfExprList(p->pEList, pnHeight);
heightOfExprList(p->pGroupBy, pnHeight);
heightOfExprList(p->pOrderBy, pnHeight);
heightOfSelect(p->pPrior, 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.
*/
static void exprSetHeight(Expr *p){
int nHeight = 0;
heightOfExpr(p->pLeft, &nHeight);
heightOfExpr(p->pRight, &nHeight);
heightOfExprList(p->pList, &nHeight);
heightOfSelect(p->pSelect, &nHeight);
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.
*/
void sqlite3ExprSetHeight(Parse *pParse, Expr *p){
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
#define exprSetHeight(y)
#endif /* SQLITE_MAX_EXPR_DEPTH>0 */
/*
** Construct a new expression node and return a pointer to it. Memory
** for this node is obtained from sqlite3_malloc(). The calling function
** is responsible for making sure the node eventually gets freed.
*/
Expr *sqlite3Expr(
sqlite3 *db, /* Handle for sqlite3DbMallocZero() (may be null) */
int op, /* Expression opcode */
Expr *pLeft, /* Left operand */
Expr *pRight, /* Right operand */
const Token *pToken /* Argument token */
){
Expr *pNew;
pNew = sqlite3DbMallocZero(db, sizeof(Expr));
if( pNew==0 ){
/* When malloc fails, delete pLeft and pRight. Expressions passed to
** this function must always be allocated with sqlite3Expr() for this
** reason.
*/
sqlite3ExprDelete(db, pLeft);
sqlite3ExprDelete(db, pRight);
return 0;
}
pNew->op = op;
pNew->pLeft = pLeft;
pNew->pRight = pRight;
pNew->iAgg = -1;
pNew->span.z = (u8*)"";
if( pToken ){
assert( pToken->dyn==0 );
pNew->span = pNew->token = *pToken;
}else if( pLeft ){
if( pRight ){
if( pRight->span.dyn==0 && pLeft->span.dyn==0 ){
sqlite3ExprSpan(pNew, &pLeft->span, &pRight->span);
}
if( pRight->flags & EP_ExpCollate ){
pNew->flags |= EP_ExpCollate;
pNew->pColl = pRight->pColl;
}
}
if( pLeft->flags & EP_ExpCollate ){
pNew->flags |= EP_ExpCollate;
pNew->pColl = pLeft->pColl;
}
}
exprSetHeight(pNew);
return pNew;
}
/*
** Works like sqlite3Expr() except that it takes an extra Parse*
** argument and notifies the associated connection object if malloc fails.
*/
Expr *sqlite3PExpr(
Parse *pParse, /* Parsing context */
int op, /* Expression opcode */
Expr *pLeft, /* Left operand */
Expr *pRight, /* Right operand */
const Token *pToken /* Argument token */
){
Expr *p = sqlite3Expr(pParse->db, op, pLeft, pRight, pToken);
if( p ){
sqlite3ExprCheckHeight(pParse, p->nHeight);
}
return p;
}
/*
** When doing a nested parse, you can include terms in an expression
** that look like this: #1 #2 ... These terms refer to registers
** in the virtual machine. #N is the N-th register.
**
** This routine is called by the parser to deal with on of those terms.
** It immediately generates code to store the value in a memory location.
** The returns an expression that will code to extract the value from
** that memory location as needed.
*/
Expr *sqlite3RegisterExpr(Parse *pParse, Token *pToken){
Vdbe *v = pParse->pVdbe;
Expr *p;
if( pParse->nested==0 ){
sqlite3ErrorMsg(pParse, "near \"%T\": syntax error", pToken);
return sqlite3PExpr(pParse, TK_NULL, 0, 0, 0);
}
if( v==0 ) return 0;
p = sqlite3PExpr(pParse, TK_REGISTER, 0, 0, pToken);
if( p==0 ){
return 0; /* Malloc failed */
}
p->iTable = atoi((char*)&pToken->z[1]);
return p;
}
/*
** Join two expressions using an AND operator. If either expression is
** NULL, then just return the other expression.
*/
Expr *sqlite3ExprAnd(sqlite3 *db, Expr *pLeft, Expr *pRight){
if( pLeft==0 ){
return pRight;
}else if( pRight==0 ){
return pLeft;
}else{
return sqlite3Expr(db, TK_AND, pLeft, pRight, 0);
}
}
/*
** Set the Expr.span field of the given expression to span all
** text between the two given tokens. Both tokens must be pointing
** at the same string.
*/
void sqlite3ExprSpan(Expr *pExpr, Token *pLeft, Token *pRight){
assert( pRight!=0 );
assert( pLeft!=0 );
if( pExpr ){
pExpr->span.z = pLeft->z;
pExpr->span.n = pRight->n + (pRight->z - pLeft->z);
}
}
/*
** 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 = sqlite3DbMallocZero(db, sizeof(Expr) );
if( pNew==0 ){
sqlite3ExprListDelete(db, pList); /* Avoid leaking memory when malloc fails */
return 0;
}
pNew->op = TK_FUNCTION;
pNew->pList = pList;
assert( pToken->dyn==0 );
pNew->token = *pToken;
pNew->span = pNew->token;
sqlite3ExprSetHeight(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 be to avoid a denial of service attack when
** the SQL statement comes from an external source.
**
** Wildcards of the form ":aaa" or "$aaa" are assigned the same number
** as the previous instance of the same wildcard. Or if this is the first
** instance of the wildcard, the next sequenial variable number is
** assigned.
*/
void sqlite3ExprAssignVarNumber(Parse *pParse, Expr *pExpr){
Token *pToken;
sqlite3 *db = pParse->db;
if( pExpr==0 ) return;
pToken = &pExpr->token;
assert( pToken->n>=1 );
assert( pToken->z!=0 );
assert( pToken->z[0]!=0 );
if( pToken->n==1 ){
/* Wildcard of the form "?". Assign the next variable number */
pExpr->iTable = ++pParse->nVar;
}else if( pToken->z[0]=='?' ){
/* Wildcard of the form "?nnn". Convert "nnn" to an integer and
** use it as the variable number */
int i;
pExpr->iTable = i = atoi((char*)&pToken->z[1]);
testcase( i==0 );
testcase( i==1 );
testcase( i==db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER]-1 );
testcase( i==db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] );
if( i<1 || i>db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] ){
sqlite3ErrorMsg(pParse, "variable number must be between ?1 and ?%d",
db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER]);
}
if( i>pParse->nVar ){
pParse->nVar = i;
}
}else{
/* Wildcards of the form ":aaa" or "$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
*/
int i, n;
n = pToken->n;
for(i=0; i<pParse->nVarExpr; i++){
Expr *pE;
if( (pE = pParse->apVarExpr[i])!=0
&& pE->token.n==n
&& memcmp(pE->token.z, pToken->z, n)==0 ){
pExpr->iTable = pE->iTable;
break;
}
}
if( i>=pParse->nVarExpr ){
pExpr->iTable = ++pParse->nVar;
if( pParse->nVarExpr>=pParse->nVarExprAlloc-1 ){
pParse->nVarExprAlloc += pParse->nVarExprAlloc + 10;
pParse->apVarExpr =
sqlite3DbReallocOrFree(
db,
pParse->apVarExpr,
pParse->nVarExprAlloc*sizeof(pParse->apVarExpr[0])
);
}
if( !db->mallocFailed ){
assert( pParse->apVarExpr!=0 );
pParse->apVarExpr[pParse->nVarExpr++] = pExpr;
}
}
}
if( !pParse->nErr && pParse->nVar>db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] ){
sqlite3ErrorMsg(pParse, "too many SQL variables");
}
}
/*
** Clear an expression structure without deleting the structure itself.
** Substructure is deleted.
*/
void sqlite3ExprClear(sqlite3 *db, Expr *p){
if( p->span.dyn ) sqlite3DbFree(db, (char*)p->span.z);
if( p->token.dyn ) sqlite3DbFree(db, (char*)p->token.z);
sqlite3ExprDelete(db, p->pLeft);
sqlite3ExprDelete(db, p->pRight);
sqlite3ExprListDelete(db, p->pList);
sqlite3SelectDelete(db, p->pSelect);
}
/*
** Recursively delete an expression tree.
*/
void sqlite3ExprDelete(sqlite3 *db, Expr *p){
if( p==0 ) return;
sqlite3ExprClear(db, p);
sqlite3DbFree(db, p);
}
/*
** The Expr.token field might be a string literal that is quoted.
** If so, remove the quotation marks.
*/
void sqlite3DequoteExpr(sqlite3 *db, Expr *p){
if( ExprHasAnyProperty(p, EP_Dequoted) ){
return;
}
ExprSetProperty(p, EP_Dequoted);
if( p->token.dyn==0 ){
sqlite3TokenCopy(db, &p->token, &p->token);
}
sqlite3Dequote((char*)p->token.z);
}
/*
** 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.
*/
Expr *sqlite3ExprDup(sqlite3 *db, Expr *p){
Expr *pNew;
if( p==0 ) return 0;
pNew = sqlite3DbMallocRaw(db, sizeof(*p) );
if( pNew==0 ) return 0;
memcpy(pNew, p, sizeof(*pNew));
if( p->token.z!=0 ){
pNew->token.z = (u8*)sqlite3DbStrNDup(db, (char*)p->token.z, p->token.n);
pNew->token.dyn = 1;
}else{
assert( pNew->token.z==0 );
}
pNew->span.z = 0;
pNew->pLeft = sqlite3ExprDup(db, p->pLeft);
pNew->pRight = sqlite3ExprDup(db, p->pRight);
pNew->pList = sqlite3ExprListDup(db, p->pList);
pNew->pSelect = sqlite3SelectDup(db, p->pSelect);
return pNew;
}
void sqlite3TokenCopy(sqlite3 *db, Token *pTo, Token *pFrom){
if( pTo->dyn ) sqlite3DbFree(db, (char*)pTo->z);
if( pFrom->z ){
pTo->n = pFrom->n;
pTo->z = (u8*)sqlite3DbStrNDup(db, (char*)pFrom->z, pFrom->n);
pTo->dyn = 1;
}else{
pTo->z = 0;
}
}
ExprList *sqlite3ExprListDup(sqlite3 *db, ExprList *p){
ExprList *pNew;
struct ExprList_item *pItem, *pOldItem;
int i;
if( p==0 ) return 0;
pNew = sqlite3DbMallocRaw(db, sizeof(*pNew) );
if( pNew==0 ) return 0;
pNew->iECursor = 0;
pNew->nExpr = pNew->nAlloc = p->nExpr;
pNew->a = pItem = sqlite3DbMallocRaw(db, p->nExpr*sizeof(p->a[0]) );
if( pItem==0 ){
sqlite3DbFree(db, pNew);
return 0;
}
pOldItem = p->a;
for(i=0; i<p->nExpr; i++, pItem++, pOldItem++){
Expr *pNewExpr, *pOldExpr;
pItem->pExpr = pNewExpr = sqlite3ExprDup(db, pOldExpr = pOldItem->pExpr);
if( pOldExpr->span.z!=0 && pNewExpr ){
/* Always make a copy of the span for top-level expressions in the
** expression list. The logic in SELECT processing that determines
** the names of columns in the result set needs this information */
sqlite3TokenCopy(db, &pNewExpr->span, &pOldExpr->span);
}
assert( pNewExpr==0 || pNewExpr->span.z!=0
|| pOldExpr->span.z==0
|| db->mallocFailed );
pItem->zName = sqlite3DbStrDup(db, pOldItem->zName);
pItem->sortOrder = pOldItem->sortOrder;
pItem->done = 0;
pItem->iCol = pOldItem->iCol;
pItem->iAlias = pOldItem->iAlias;
}
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){
SrcList *pNew;
int i;
int nByte;
if( p==0 ) return 0;
nByte = sizeof(*p) + (p->nSrc>0 ? sizeof(p->a[0]) * (p->nSrc-1) : 0);
pNew = sqlite3DbMallocRaw(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->zDatabase = sqlite3DbStrDup(db, pOldItem->zDatabase);
pNewItem->zName = sqlite3DbStrDup(db, pOldItem->zName);
pNewItem->zAlias = sqlite3DbStrDup(db, pOldItem->zAlias);
pNewItem->jointype = pOldItem->jointype;
pNewItem->iCursor = pOldItem->iCursor;
pNewItem->isPopulated = pOldItem->isPopulated;
pNewItem->zIndex = sqlite3DbStrDup(db, pOldItem->zIndex);
pNewItem->notIndexed = pOldItem->notIndexed;
pNewItem->pIndex = pOldItem->pIndex;
pTab = pNewItem->pTab = pOldItem->pTab;
if( pTab ){
pTab->nRef++;
}
pNewItem->pSelect = sqlite3SelectDup(db, pOldItem->pSelect);
pNewItem->pOn = sqlite3ExprDup(db, pOldItem->pOn);
pNewItem->pUsing = sqlite3IdListDup(db, pOldItem->pUsing);
pNewItem->colUsed = pOldItem->colUsed;
}
return pNew;
}
IdList *sqlite3IdListDup(sqlite3 *db, IdList *p){
IdList *pNew;
int i;
if( p==0 ) return 0;
pNew = sqlite3DbMallocRaw(db, sizeof(*pNew) );
if( pNew==0 ) return 0;
pNew->nId = pNew->nAlloc = p->nId;
pNew->a = sqlite3DbMallocRaw(db, p->nId*sizeof(p->a[0]) );
if( pNew->a==0 ){
sqlite3DbFree(db, pNew);
return 0;
}
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 *p){
Select *pNew;
if( p==0 ) return 0;
pNew = sqlite3DbMallocRaw(db, sizeof(*p) );
if( pNew==0 ) return 0;
pNew->pEList = sqlite3ExprListDup(db, p->pEList);
pNew->pSrc = sqlite3SrcListDup(db, p->pSrc);
pNew->pWhere = sqlite3ExprDup(db, p->pWhere);
pNew->pGroupBy = sqlite3ExprListDup(db, p->pGroupBy);
pNew->pHaving = sqlite3ExprDup(db, p->pHaving);
pNew->pOrderBy = sqlite3ExprListDup(db, p->pOrderBy);
pNew->op = p->op;
pNew->pPrior = sqlite3SelectDup(db, p->pPrior);
pNew->pLimit = sqlite3ExprDup(db, p->pLimit);
pNew->pOffset = sqlite3ExprDup(db, p->pOffset);
pNew->iLimit = 0;
pNew->iOffset = 0;
pNew->selFlags = p->selFlags & ~SF_UsesEphemeral;
pNew->pRightmost = 0;
pNew->addrOpenEphm[0] = -1;
pNew->addrOpenEphm[1] = -1;
pNew->addrOpenEphm[2] = -1;
return pNew;
}
#else
Select *sqlite3SelectDup(sqlite3 *db, Select *p){
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.
*/
ExprList *sqlite3ExprListAppend(
Parse *pParse, /* Parsing context */
ExprList *pList, /* List to which to append. Might be NULL */
Expr *pExpr, /* Expression to be appended */
Token *pName /* AS keyword for the expression */
){
sqlite3 *db = pParse->db;
if( pList==0 ){
pList = sqlite3DbMallocZero(db, sizeof(ExprList) );
if( pList==0 ){
goto no_mem;
}
assert( pList->nAlloc==0 );
}
if( pList->nAlloc<=pList->nExpr ){
struct ExprList_item *a;
int n = pList->nAlloc*2 + 4;
a = sqlite3DbRealloc(db, pList->a, n*sizeof(pList->a[0]));
if( a==0 ){
goto no_mem;
}
pList->a = a;
pList->nAlloc = n;
}
assert( pList->a!=0 );
if( pExpr || pName ){
struct ExprList_item *pItem = &pList->a[pList->nExpr++];
memset(pItem, 0, sizeof(*pItem));
pItem->zName = sqlite3NameFromToken(db, pName);
pItem->pExpr = pExpr;
pItem->iAlias = 0;
}
return pList;
no_mem:
/* Avoid leaking memory if malloc has failed. */
sqlite3ExprDelete(db, pExpr);
sqlite3ExprListDelete(db, pList);
return 0;
}
/*
** 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.
*/
void sqlite3ExprListDelete(sqlite3 *db, ExprList *pList){
int i;
struct ExprList_item *pItem;
if( pList==0 ) return;
assert( pList->a!=0 || (pList->nExpr==0 && pList->nAlloc==0) );
assert( pList->nExpr<=pList->nAlloc );
for(pItem=pList->a, i=0; i<pList->nExpr; i++, pItem++){
sqlite3ExprDelete(db, pItem->pExpr);
sqlite3DbFree(db, pItem->zName);
}
sqlite3DbFree(db, pList->a);
sqlite3DbFree(db, pList);
}
/*
** These routines are Walker callbacks. Walker.u.pi is a pointer
** to an integer. These routines are checking an expression to see
** if it is a constant. Set *Walker.u.pi to 0 if the expression is
** not constant.
**
** These callback routines are used to implement the following:
**
** sqlite3ExprIsConstant()
** sqlite3ExprIsConstantNotJoin()
** sqlite3ExprIsConstantOrFunction()
**
*/
static int exprNodeIsConstant(Walker *pWalker, Expr *pExpr){
/* If pWalker->u.i is 3 then any term of the expression that comes from
** the ON or USING clauses of a join disqualifies the expression
** from being considered constant. */
if( pWalker->u.i==3 && ExprHasAnyProperty(pExpr, EP_FromJoin) ){
pWalker->u.i = 0;
return WRC_Abort;
}
switch( pExpr->op ){
/* Consider functions to be constant if all their arguments are constant
** and pWalker->u.i==2 */
case TK_FUNCTION:
if( pWalker->u.i==2 ) return 0;
/* Fall through */
case TK_ID:
case TK_COLUMN:
case TK_DOT:
case TK_AGG_FUNCTION:
case TK_AGG_COLUMN:
#ifndef SQLITE_OMIT_SUBQUERY
case TK_SELECT:
case TK_EXISTS:
testcase( pExpr->op==TK_SELECT );
testcase( pExpr->op==TK_EXISTS );
#endif
testcase( pExpr->op==TK_ID );
testcase( pExpr->op==TK_COLUMN );
testcase( pExpr->op==TK_DOT );
testcase( pExpr->op==TK_AGG_FUNCTION );
testcase( pExpr->op==TK_AGG_COLUMN );
pWalker->u.i = 0;
return WRC_Abort;
default:
return WRC_Continue;
}
}
static int selectNodeIsConstant(Walker *pWalker, Select *pSelect){
pWalker->u.i = 0;
return WRC_Abort;
}
static int exprIsConst(Expr *p, int initFlag){
Walker w;
w.u.i = initFlag;
w.xExprCallback = exprNodeIsConstant;
w.xSelectCallback = selectNodeIsConstant;
sqlite3WalkExpr(&w, p);
return w.u.i;
}
/*
** Walk an expression tree. Return 1 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);
}
/*
** Walk an expression tree. Return 1 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, 3);
}
/*
** Walk an expression tree. Return 1 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){
return exprIsConst(p, 2);
}
/*
** 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->flags & EP_IntValue ){
*pValue = p->iTable;
return 1;
}
switch( p->op ){
case TK_INTEGER: {
rc = sqlite3GetInt32((char*)p->token.z, pValue);
break;
}
case TK_UPLUS: {
rc = sqlite3ExprIsInteger(p->pLeft, pValue);
break;
}
case TK_UMINUS: {
int v;
if( sqlite3ExprIsInteger(p->pLeft, &v) ){
*pValue = -v;
rc = 1;
}
break;
}
default: break;
}
if( rc ){
p->op = TK_INTEGER;
p->flags |= EP_IntValue;
p->iTable = *pValue;
}
return rc;
}
/*
** 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;
}
#ifdef SQLITE_TEST
int sqlite3_enable_in_opt = 1;
#else
#define sqlite3_enable_in_opt 1
#endif
/*
** Return true if the IN operator optimization is enabled and
** the SELECT statement p exists and is of the
** simple form:
**
** SELECT <column> FROM <table>
**
** If this is the case, it may be possible to use an existing table
** or index instead of generating an epheremal table.
*/
#ifndef SQLITE_OMIT_SUBQUERY
static int isCandidateForInOpt(Select *p){
SrcList *pSrc;
ExprList *pEList;
Table *pTab;
if( !sqlite3_enable_in_opt ) return 0; /* IN optimization must be enabled */
if( p==0 ) return 0; /* right-hand side of IN is SELECT */
if( p->pPrior ) return 0; /* Not a compound SELECT */
if( p->selFlags & (SF_Distinct|SF_Aggregate) ){
return 0; /* No DISTINCT keyword and no aggregate functions */
}
if( p->pGroupBy ) return 0; /* Has no GROUP BY clause */
if( p->pLimit ) return 0; /* Has no LIMIT clause */
if( p->pOffset ) return 0;
if( p->pWhere ) return 0; /* Has no WHERE clause */
pSrc = p->pSrc;
if( pSrc==0 ) return 0; /* A single table in the FROM clause */
if( pSrc->nSrc!=1 ) return 0;
if( pSrc->a[0].pSelect ) return 0; /* FROM clause is not a subquery */
pTab = pSrc->a[0].pTab;
if( pTab==0 ) return 0;
if( pTab->pSelect ) return 0; /* FROM clause is not a view */
if( IsVirtual(pTab) ) return 0; /* FROM clause not a virtual table */
pEList = p->pEList;
if( pEList->nExpr!=1 ) return 0; /* One column in the result set */
if( pEList->a[0].pExpr->op!=TK_COLUMN ) return 0; /* Result is a column */
return 1;
}
#endif /* SQLITE_OMIT_SUBQUERY */
/*
** This function is used by the implementation of the IN (...) operator.
** It's job is to find or create a b-tree structure that may be used
** either to test for membership of the (...) set or to iterate through
** its members, skipping duplicates.
**
** The cursor opened on the structure (database table, database index
** or ephermal table) is stored in pX->iTable before this function returns.
** The returned value indicates the structure type, as follows:
**
** IN_INDEX_ROWID - The cursor was opened on a database table.
** IN_INDEX_INDEX - The cursor was opened on a database index.
** IN_INDEX_EPH - The cursor was opened on a specially created and
** populated epheremal table.
**
** An existing structure may only be used if the SELECT is of the simple
** form:
**
** SELECT <column> FROM <table>
**
** If prNotFound parameter is 0, then the structure will be used to iterate
** through the set members, skipping any duplicates. In this case an
** epheremal table must be used unless the selected <column> is guaranteed
** to be unique - either because it is an INTEGER PRIMARY KEY or it
** is unique by virtue of a constraint or implicit index.
**
** If the prNotFound parameter is not 0, then the structure will be used
** for fast set membership tests. In this case an epheremal table must
** be used unless <column> is an INTEGER PRIMARY KEY or an index can
** be found with <column> as its left-most column.
**
** When the structure is being used for set membership tests, the user
** needs to know whether or not the structure contains an SQL NULL
** value in order to correctly evaluate expressions like "X IN (Y, Z)".
** If there is a chance that the structure may contain a NULL value at
** runtime, then a register is allocated and the register number written
** to *prNotFound. If there is no chance that the structure contains a
** NULL value, then *prNotFound is left unchanged.
**
** If a register is allocated and its location stored in *prNotFound, then
** its initial value is NULL. If the structure does not remain constant
** for the duration of the query (i.e. the set is a correlated sub-select),
** the value of the allocated register is reset to NULL each time the
** structure is repopulated. This allows the caller to use vdbe code
** equivalent to the following:
**
** if( register==NULL ){
** has_null = <test if data structure contains null>
** register = 1
** }
**
** in order to avoid running the <test if data structure contains null>
** test more often than is necessary.
*/
#ifndef SQLITE_OMIT_SUBQUERY
int sqlite3FindInIndex(Parse *pParse, Expr *pX, int *prNotFound){
Select *p;
int eType = 0;
int iTab = pParse->nTab++;
int mustBeUnique = !prNotFound;
/* The follwing if(...) expression is true if the SELECT is of the
** simple form:
**
** SELECT <column> FROM <table>
**
** If this is the case, it may be possible to use an existing table
** or index instead of generating an epheremal table.
*/
p = pX->pSelect;
if( isCandidateForInOpt(p) ){
sqlite3 *db = pParse->db;
Index *pIdx;
Expr *pExpr = p->pEList->a[0].pExpr;
int iCol = pExpr->iColumn;
Vdbe *v = sqlite3GetVdbe(pParse);
/* This function is only called from two places. In both cases the vdbe
** has already been allocated. So assume sqlite3GetVdbe() is always
** successful here.
*/
assert(v);
if( iCol<0 ){
int iMem = ++pParse->nMem;
int iAddr;
Table *pTab = p->pSrc->a[0].pTab;
int iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
sqlite3VdbeUsesBtree(v, iDb);
iAddr = sqlite3VdbeAddOp1(v, OP_If, iMem);
sqlite3VdbeAddOp2(v, OP_Integer, 1, iMem);
sqlite3OpenTable(pParse, iTab, iDb, pTab, OP_OpenRead);
eType = IN_INDEX_ROWID;
sqlite3VdbeJumpHere(v, iAddr);
}else{
/* The collation sequence used by the comparison. If an index is to
** be used in place of a temp-table, it must be ordered according
** to this collation sequence.
*/
CollSeq *pReq = sqlite3BinaryCompareCollSeq(pParse, pX->pLeft, pExpr);
/* Check that the affinity that will be used to perform the
** comparison is the same as the affinity of the column. If
** it is not, it is not possible to use any index.
*/
Table *pTab = p->pSrc->a[0].pTab;
char aff = comparisonAffinity(pX);
int affinity_ok = (pTab->aCol[iCol].affinity==aff||aff==SQLITE_AFF_NONE);
for(pIdx=pTab->pIndex; pIdx && eType==0 && affinity_ok; pIdx=pIdx->pNext){
if( (pIdx->aiColumn[0]==iCol)
&& (pReq==sqlite3FindCollSeq(db, ENC(db), pIdx->azColl[0], -1, 0))
&& (!mustBeUnique || (pIdx->nColumn==1 && pIdx->onError!=OE_None))
){
int iDb;
int iMem = ++pParse->nMem;
int iAddr;
char *pKey;
pKey = (char *)sqlite3IndexKeyinfo(pParse, pIdx);
iDb = sqlite3SchemaToIndex(db, pIdx->pSchema);
sqlite3VdbeUsesBtree(v, iDb);
iAddr = sqlite3VdbeAddOp1(v, OP_If, iMem);
sqlite3VdbeAddOp2(v, OP_Integer, 1, iMem);
sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, pIdx->nColumn);
sqlite3VdbeAddOp4(v, OP_OpenRead, iTab, pIdx->tnum, iDb,
pKey,P4_KEYINFO_HANDOFF);
VdbeComment((v, "%s", pIdx->zName));
eType = IN_INDEX_INDEX;
sqlite3VdbeJumpHere(v, iAddr);
if( prNotFound && !pTab->aCol[iCol].notNull ){
*prNotFound = ++pParse->nMem;
}
}
}
}
}
if( eType==0 ){
int rMayHaveNull = 0;
eType = IN_INDEX_EPH;
if( prNotFound ){
*prNotFound = rMayHaveNull = ++pParse->nMem;
}else if( pX->pLeft->iColumn<0 && pX->pSelect==0 ){
eType = IN_INDEX_ROWID;
}
sqlite3CodeSubselect(pParse, pX, rMayHaveNull, eType==IN_INDEX_ROWID);
}else{
pX->iTable = iTab;
}
return eType;
}
#endif
/*
** Generate code for scalar subqueries used as an expression
** and 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.
*/
#ifndef SQLITE_OMIT_SUBQUERY
void sqlite3CodeSubselect(
Parse *pParse,
Expr *pExpr,
int rMayHaveNull,
int isRowid
){
int testAddr = 0; /* One-time test address */
Vdbe *v = sqlite3GetVdbe(pParse);
if( v==0 ) return;
/* This code must be run in its entirety 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( !ExprHasAnyProperty(pExpr, EP_VarSelect) && !pParse->trigStack ){
int mem = ++pParse->nMem;
sqlite3VdbeAddOp1(v, OP_If, mem);
testAddr = sqlite3VdbeAddOp2(v, OP_Integer, 1, mem);
assert( testAddr>0 || pParse->db->mallocFailed );
}
switch( pExpr->op ){
case TK_IN: {
char affinity;
KeyInfo keyInfo;
int addr; /* Address of OP_OpenEphemeral instruction */
Expr *pLeft = pExpr->pLeft;
if( rMayHaveNull ){
sqlite3VdbeAddOp2(v, OP_Null, 0, rMayHaveNull);
}
affinity = sqlite3ExprAffinity(pLeft);
/* Whether this is an 'x IN(SELECT...)' or an 'x IN(<exprlist>)'
** expression it is handled the same way. A virtual table is
** filled with single-field 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);
memset(&keyInfo, 0, sizeof(keyInfo));
keyInfo.nField = 1;
if( pExpr->pSelect ){
/* Case 1: expr IN (SELECT ...)
**
** Generate code to write the results of the select into the temporary
** table allocated and opened above.
*/
SelectDest dest;
ExprList *pEList;
assert( !isRowid );
sqlite3SelectDestInit(&dest, SRT_Set, pExpr->iTable);
dest.affinity = (int)affinity;
assert( (pExpr->iTable&0x0000FFFF)==pExpr->iTable );
if( sqlite3Select(pParse, pExpr->pSelect, &dest) ){
return;
}
pEList = pExpr->pSelect->pEList;
if( pEList && pEList->nExpr>0 ){
keyInfo.aColl[0] = sqlite3BinaryCompareCollSeq(pParse, pExpr->pLeft,
pEList->a[0].pExpr);
}
}else if( pExpr->pList ){
/* 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.
*/
int i;
ExprList *pList = pExpr->pList;
struct ExprList_item *pItem;
int r1, r2, r3;
if( !affinity ){
affinity = SQLITE_AFF_NONE;
}
keyInfo.aColl[0] = sqlite3ExprCollSeq(pParse, pExpr->pLeft);
/* Loop through each expression in <exprlist>. */
r1 = sqlite3GetTempReg(pParse);
r2 = sqlite3GetTempReg(pParse);
sqlite3VdbeAddOp2(v, OP_Null, 0, r2);
for(i=pList->nExpr, pItem=pList->a; i>0; i--, pItem++){
Expr *pE2 = pItem->pExpr;
/* 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( testAddr && !sqlite3ExprIsConstant(pE2) ){
sqlite3VdbeChangeToNoop(v, testAddr-1, 2);
testAddr = 0;
}
/* Evaluate the expression and insert it into the temp table */
pParse->disableColCache++;
r3 = sqlite3ExprCodeTarget(pParse, pE2, r1);
assert( pParse->disableColCache>0 );
pParse->disableColCache--;
if( isRowid ){
sqlite3VdbeAddOp2(v, OP_MustBeInt, r3, sqlite3VdbeCurrentAddr(v)+2);
sqlite3VdbeAddOp3(v, OP_Insert, pExpr->iTable, r2, r3);
}else{
sqlite3VdbeAddOp4(v, OP_MakeRecord, r3, 1, r2, &affinity, 1);
sqlite3ExprCacheAffinityChange(pParse, r3, 1);
sqlite3VdbeAddOp2(v, OP_IdxInsert, pExpr->iTable, r2);
}
}
sqlite3ReleaseTempReg(pParse, r1);
sqlite3ReleaseTempReg(pParse, r2);
}
if( !isRowid ){
sqlite3VdbeChangeP4(v, addr, (void *)&keyInfo, P4_KEYINFO);
}
break;
}
case TK_EXISTS:
case TK_SELECT: {
/* This has to be a scalar SELECT. Generate code to put the
** value of this select in a memory cell and record the number
** of the memory cell in iColumn.
*/
static const Token one = { (u8*)"1", 0, 1 };
Select *pSel;
SelectDest dest;
pSel = pExpr->pSelect;
sqlite3SelectDestInit(&dest, 0, ++pParse->nMem);
if( pExpr->op==TK_SELECT ){
dest.eDest = SRT_Mem;
sqlite3VdbeAddOp2(v, OP_Null, 0, dest.iParm);
VdbeComment((v, "Init subquery result"));
}else{
dest.eDest = SRT_Exists;
sqlite3VdbeAddOp2(v, OP_Integer, 0, dest.iParm);
VdbeComment((v, "Init EXISTS result"));
}
sqlite3ExprDelete(pParse->db, pSel->pLimit);
pSel->pLimit = sqlite3PExpr(pParse, TK_INTEGER, 0, 0, &one);
if( sqlite3Select(pParse, pSel, &dest) ){
return;
}
pExpr->iColumn = dest.iParm;
break;
}
}
if( testAddr ){
sqlite3VdbeJumpHere(v, testAddr-1);
}
return;
}
#endif /* SQLITE_OMIT_SUBQUERY */
/*
** Duplicate an 8-byte value
*/
static char *dup8bytes(Vdbe *v, const char *in){
char *out = sqlite3DbMallocRaw(sqlite3VdbeDb(v), 8);
if( out ){
memcpy(out, in, 8);
}
return out;
}
/*
** 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 n, int negateFlag, int iMem){
assert( z || v==0 || sqlite3VdbeDb(v)->mallocFailed );
if( z ){
double value;
char *zV;
assert( !isdigit(z[n]) );
sqlite3AtoF(z, &value);
if( sqlite3IsNaN(value) ){
sqlite3VdbeAddOp2(v, OP_Null, 0, iMem);
}else{
if( negateFlag ) value = -value;
zV = dup8bytes(v, (char*)&value);
sqlite3VdbeAddOp4(v, OP_Real, 0, iMem, 0, zV, P4_REAL);
}
}
}
/*
** Generate an instruction that will put the integer describe by
** text 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 codeInteger(Vdbe *v, Expr *pExpr, int negFlag, int iMem){
const char *z;
if( pExpr->flags & EP_IntValue ){
int i = pExpr->iTable;
if( negFlag ) i = -i;
sqlite3VdbeAddOp2(v, OP_Integer, i, iMem);
}else if( (z = (char*)pExpr->token.z)!=0 ){
int i;
int n = pExpr->token.n;
assert( !isdigit(z[n]) );
if( sqlite3GetInt32(z, &i) ){
if( negFlag ) i = -i;
sqlite3VdbeAddOp2(v, OP_Integer, i, iMem);
}else if( sqlite3FitsIn64Bits(z, negFlag) ){
i64 value;
char *zV;
sqlite3Atoi64(z, &value);
if( negFlag ) value = -value;
zV = dup8bytes(v, (char*)&value);
sqlite3VdbeAddOp4(v, OP_Int64, 0, iMem, 0, zV, P4_INT64);
}else{
codeReal(v, z, n, negFlag, iMem);
}
}
}
/*
** 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, but this is
** not guaranteed. The location of the column value is returned.
**
** 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.
**
** This routine might attempt to reuse the value of the column that
** has already been loaded into a register. The value will always
** be used if it has not undergone any affinity changes. But if
** an affinity change has occurred, then the cached value will only be
** used if allowAffChng is true.
*/
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 */
int allowAffChng /* True if prior affinity changes are OK */
){
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->affChange || allowAffChng) ){
#if 0
sqlite3VdbeAddOp0(v, OP_Noop);
VdbeComment((v, "OPT: tab%d.col%d -> r%d", iTable, iColumn, p->iReg));
#endif
return p->iReg;
}
}
assert( v!=0 );
if( iColumn<0 ){
int op = (pTab && IsVirtual(pTab)) ? OP_VRowid : OP_Rowid;
sqlite3VdbeAddOp2(v, op, iTable, iReg);
}else if( pTab==0 ){
sqlite3VdbeAddOp3(v, OP_Column, iTable, iColumn, iReg);
}else{
int op = IsVirtual(pTab) ? OP_VColumn : OP_Column;
sqlite3VdbeAddOp3(v, op, iTable, iColumn, iReg);
sqlite3ColumnDefault(v, pTab, iColumn);
#ifndef SQLITE_OMIT_FLOATING_POINT
if( pTab->aCol[iColumn].affinity==SQLITE_AFF_REAL ){
sqlite3VdbeAddOp1(v, OP_RealAffinity, iReg);
}
#endif
}
if( pParse->disableColCache==0 ){
i = pParse->iColCache;
p = &pParse->aColCache[i];
p->iTable = iTable;
p->iColumn = iColumn;
p->iReg = iReg;
p->affChange = 0;
i++;
if( i>=ArraySize(pParse->aColCache) ) i = 0;
if( i>pParse->nColCache ) pParse->nColCache = i;
pParse->iColCache = i;
}
return iReg;
}
/*
** Clear all column cache entries associated with the vdbe
** cursor with cursor number iTable.
*/
void sqlite3ExprClearColumnCache(Parse *pParse, int iTable){
if( iTable<0 ){
pParse->nColCache = 0;
pParse->iColCache = 0;
}else{
int i;
for(i=0; i<pParse->nColCache; i++){
if( pParse->aColCache[i].iTable==iTable ){
testcase( i==pParse->nColCache-1 );
pParse->aColCache[i] = pParse->aColCache[--pParse->nColCache];
pParse->iColCache = pParse->nColCache;
}
}
}
}
/*
** Record the fact that an affinity change has occurred on iCount
** registers starting with iStart.
*/
void sqlite3ExprCacheAffinityChange(Parse *pParse, int iStart, int iCount){
int iEnd = iStart + iCount - 1;
int i;
for(i=0; i<pParse->nColCache; i++){
int r = pParse->aColCache[i].iReg;
if( r>=iStart && r<=iEnd ){
pParse->aColCache[i].affChange = 1;
}
}
}
/*
** 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){
int i;
if( iFrom==iTo ) return;
sqlite3VdbeAddOp3(pParse->pVdbe, OP_Move, iFrom, iTo, nReg);
for(i=0; i<pParse->nColCache; i++){
int x = pParse->aColCache[i].iReg;
if( x>=iFrom && x<iFrom+nReg ){
pParse->aColCache[i].iReg += iTo-iFrom;
}
}
}
/*
** Generate code to copy content from registers iFrom...iFrom+nReg-1
** over to iTo..iTo+nReg-1.
*/
void sqlite3ExprCodeCopy(Parse *pParse, int iFrom, int iTo, int nReg){
int i;
if( iFrom==iTo ) return;
for(i=0; i<nReg; i++){
sqlite3VdbeAddOp2(pParse->pVdbe, OP_Copy, iFrom+i, iTo+i);
}
}
/*
** Return true if any register in the range iFrom..iTo (inclusive)
** is used as part of the column cache.
*/
static int usedAsColumnCache(Parse *pParse, int iFrom, int iTo){
int i;
for(i=0; i<pParse->nColCache; i++){
int r = pParse->aColCache[i].iReg;
if( r>=iFrom && r<=iTo ) return 1;
}
return 0;
}
/*
** Theres is a value in register iCurrent. We ultimately want
** the value to be in register iTarget. It might be that
** iCurrent and iTarget are the same register.
**
** We are going to modify the value, so we need to make sure it
** is not a cached register. If iCurrent is a cached register,
** then try to move the value over to iTarget. If iTarget is a
** cached register, then clear the corresponding cache line.
**
** Return the register that the value ends up in.
*/
int sqlite3ExprWritableRegister(Parse *pParse, int iCurrent, int iTarget){
int i;
assert( pParse->pVdbe!=0 );
if( !usedAsColumnCache(pParse, iCurrent, iCurrent) ){
return iCurrent;
}
if( iCurrent!=iTarget ){
sqlite3VdbeAddOp2(pParse->pVdbe, OP_SCopy, iCurrent, iTarget);
}
for(i=0; i<pParse->nColCache; i++){
if( pParse->aColCache[i].iReg==iTarget ){
pParse->aColCache[i] = pParse->aColCache[--pParse->nColCache];
pParse->iColCache = pParse->nColCache;
}
}
return iTarget;
}
/*
** If the last instruction coded is an ephemeral copy of any of
** the registers in the nReg registers beginning with iReg, then
** convert the last instruction from OP_SCopy to OP_Copy.
*/
void sqlite3ExprHardCopy(Parse *pParse, int iReg, int nReg){
int addr;
VdbeOp *pOp;
Vdbe *v;
v = pParse->pVdbe;
addr = sqlite3VdbeCurrentAddr(v);
pOp = sqlite3VdbeGetOp(v, addr-1);
assert( pOp || pParse->db->mallocFailed );
if( pOp && pOp->opcode==OP_SCopy && pOp->p1>=iReg && pOp->p1<iReg+nReg ){
pOp->opcode = OP_Copy;
}
}
/*
** Generate code to store the value of the iAlias-th alias in register
** target. The first time this is called, pExpr is evaluated to compute
** the value of the alias. The value is stored in an auxiliary register
** and the number of that register is returned. On subsequent calls,
** the register number is returned without generating any code.
**
** Note that in order for this to work, code must be generated in the
** same order that it is executed.
**
** Aliases are numbered starting with 1. So iAlias is in the range
** of 1 to pParse->nAlias inclusive.
**
** pParse->aAlias[iAlias-1] records the register number where the value
** of the iAlias-th alias is stored. If zero, that means that the
** alias has not yet been computed.
*/
static int codeAlias(Parse *pParse, int iAlias, Expr *pExpr, int target){
sqlite3 *db = pParse->db;
int iReg;
if( pParse->nAliasAlloc<pParse->nAlias ){
pParse->aAlias = sqlite3DbReallocOrFree(db, pParse->aAlias,
sizeof(pParse->aAlias[0])*pParse->nAlias );
testcase( db->mallocFailed && pParse->nAliasAlloc>0 );
if( db->mallocFailed ) return 0;
memset(&pParse->aAlias[pParse->nAliasAlloc], 0,
(pParse->nAlias-pParse->nAliasAlloc)*sizeof(pParse->aAlias[0]));
pParse->nAliasAlloc = pParse->nAlias;
}
assert( iAlias>0 && iAlias<=pParse->nAlias );
iReg = pParse->aAlias[iAlias-1];
if( iReg==0 ){
if( pParse->disableColCache ){
iReg = sqlite3ExprCodeTarget(pParse, pExpr, target);
}else{
iReg = ++pParse->nMem;
sqlite3ExprCode(pParse, pExpr, iReg);
pParse->aAlias[iAlias-1] = iReg;
}
}
return iReg;
}
/*
** 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, r3, r4; /* Various register numbers */
sqlite3 *db;
db = pParse->db;
assert( v!=0 || db->mallocFailed );
assert( target>0 && target<=pParse->nMem );
if( v==0 ) return 0;
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 );
inReg = pCol->iMem;
break;
}else if( pAggInfo->useSortingIdx ){
sqlite3VdbeAddOp3(v, OP_Column, pAggInfo->sortingIdx,
pCol->iSorterColumn, target);
break;
}
/* Otherwise, fall thru into the TK_COLUMN case */
}
case TK_COLUMN: {
if( pExpr->iTable<0 ){
/* This only happens when coding check constraints */
assert( pParse->ckBase>0 );
inReg = pExpr->iColumn + pParse->ckBase;
}else{
testcase( (pExpr->flags & EP_AnyAff)!=0 );
inReg = sqlite3ExprCodeGetColumn(pParse, pExpr->pTab,
pExpr->iColumn, pExpr->iTable, target,
pExpr->flags & EP_AnyAff);
}
break;
}
case TK_INTEGER: {
codeInteger(v, pExpr, 0, target);
break;
}
case TK_FLOAT: {
codeReal(v, (char*)pExpr->token.z, pExpr->token.n, 0, target);
break;
}
case TK_STRING: {
sqlite3DequoteExpr(db, pExpr);
sqlite3VdbeAddOp4(v,OP_String8, 0, target, 0,
(char*)pExpr->token.z, pExpr->token.n);
break;
}
case TK_NULL: {
sqlite3VdbeAddOp2(v, OP_Null, 0, target);
break;
}
#ifndef SQLITE_OMIT_BLOB_LITERAL
case TK_BLOB: {
int n;
const char *z;
char *zBlob;
assert( pExpr->token.n>=3 );
assert( pExpr->token.z[0]=='x' || pExpr->token.z[0]=='X' );
assert( pExpr->token.z[1]=='\'' );
assert( pExpr->token.z[pExpr->token.n-1]=='\'' );
n = pExpr->token.n - 3;
z = (char*)pExpr->token.z + 2;
zBlob = sqlite3HexToBlob(sqlite3VdbeDb(v), z, n);
sqlite3VdbeAddOp4(v, OP_Blob, n/2, target, 0, zBlob, P4_DYNAMIC);
break;
}
#endif
case TK_VARIABLE: {
sqlite3VdbeAddOp2(v, OP_Variable, pExpr->iTable, target);
if( pExpr->token.n>1 ){
sqlite3VdbeChangeP4(v, -1, (char*)pExpr->token.z, pExpr->token.n);
}
break;
}
case TK_REGISTER: {
inReg = pExpr->iTable;
break;
}
case TK_AS: {
inReg = codeAlias(pParse, pExpr->iTable, pExpr->pLeft, target);
break;
}
#ifndef SQLITE_OMIT_CAST
case TK_CAST: {
/* Expressions of the form: CAST(pLeft AS token) */
int aff, to_op;
inReg = sqlite3ExprCodeTarget(pParse, pExpr->pLeft, target);
aff = sqlite3AffinityType(&pExpr->token);
to_op = aff - SQLITE_AFF_TEXT + OP_ToText;
assert( to_op==OP_ToText || aff!=SQLITE_AFF_TEXT );
assert( to_op==OP_ToBlob || aff!=SQLITE_AFF_NONE );
assert( to_op==OP_ToNumeric || aff!=SQLITE_AFF_NUMERIC );
assert( to_op==OP_ToInt || aff!=SQLITE_AFF_INTEGER );
assert( to_op==OP_ToReal || aff!=SQLITE_AFF_REAL );
testcase( to_op==OP_ToText );
testcase( to_op==OP_ToBlob );
testcase( to_op==OP_ToNumeric );
testcase( to_op==OP_ToInt );
testcase( to_op==OP_ToReal );
if( inReg!=target ){
sqlite3VdbeAddOp2(v, OP_SCopy, inReg, target);
inReg = target;
}
sqlite3VdbeAddOp1(v, to_op, inReg);
testcase( usedAsColumnCache(pParse, inReg, inReg) );
sqlite3ExprCacheAffinityChange(pParse, inReg, 1);
break;
}
#endif /* SQLITE_OMIT_CAST */
case TK_LT:
case TK_LE:
case TK_GT:
case TK_GE:
case TK_NE:
case TK_EQ: {
assert( TK_LT==OP_Lt );
assert( TK_LE==OP_Le );
assert( TK_GT==OP_Gt );
assert( TK_GE==OP_Ge );
assert( TK_EQ==OP_Eq );
assert( TK_NE==OP_Ne );
testcase( op==TK_LT );
testcase( op==TK_LE );
testcase( op==TK_GT );
testcase( op==TK_GE );
testcase( op==TK_EQ );
testcase( op==TK_NE );
codeCompareOperands(pParse, pExpr->pLeft, &r1, ®Free1,
pExpr->pRight, &r2, ®Free2);
codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op,
r1, r2, inReg, SQLITE_STOREP2);
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 );
assert( TK_OR==OP_Or );
assert( TK_PLUS==OP_Add );
assert( TK_MINUS==OP_Subtract );
assert( TK_REM==OP_Remainder );
assert( TK_BITAND==OP_BitAnd );
assert( TK_BITOR==OP_BitOr );
assert( TK_SLASH==OP_Divide );
assert( TK_LSHIFT==OP_ShiftLeft );
assert( TK_RSHIFT==OP_ShiftRight );
assert( TK_CONCAT==OP_Concat );
testcase( op==TK_AND );
testcase( op==TK_OR );
testcase( op==TK_PLUS );
testcase( op==TK_MINUS );
testcase( op==TK_REM );
testcase( op==TK_BITAND );
testcase( op==TK_BITOR );
testcase( op==TK_SLASH );
testcase( op==TK_LSHIFT );
testcase( op==TK_RSHIFT );
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_FLOAT || pLeft->op==TK_INTEGER ){
if( pLeft->op==TK_FLOAT ){
codeReal(v, (char*)pLeft->token.z, pLeft->token.n, 1, target);
}else{
codeInteger(v, pLeft, 1, target);
}
}else{
regFree1 = r1 = sqlite3GetTempReg(pParse);
sqlite3VdbeAddOp2(v, OP_Integer, 0, r1);
r2 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free2);
sqlite3VdbeAddOp3(v, OP_Subtract, r2, r1, target);
testcase( regFree2==0 );
}
inReg = target;
break;
}
case TK_BITNOT:
case TK_NOT: {
assert( TK_BITNOT==OP_BitNot );
assert( TK_NOT==OP_Not );
testcase( op==TK_BITNOT );
testcase( op==TK_NOT );
r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1);
testcase( regFree1==0 );
inReg = target;
sqlite3VdbeAddOp2(v, op, r1, inReg);
break;
}
case TK_ISNULL:
case TK_NOTNULL: {
int addr;
assert( TK_ISNULL==OP_IsNull );
assert( TK_NOTNULL==OP_NotNull );
testcase( op==TK_ISNULL );
testcase( op==TK_NOTNULL );
sqlite3VdbeAddOp2(v, OP_Integer, 1, target);
r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1);
testcase( regFree1==0 );
addr = sqlite3VdbeAddOp1(v, op, r1);
sqlite3VdbeAddOp2(v, OP_AddImm, target, -1);
sqlite3VdbeJumpHere(v, addr);
break;
}
case TK_AGG_FUNCTION: {
AggInfo *pInfo = pExpr->pAggInfo;
if( pInfo==0 ){
sqlite3ErrorMsg(pParse, "misuse of aggregate: %T",
&pExpr->span);
}else{
inReg = pInfo->aFunc[pExpr->iAgg].iMem;
}
break;
}
case TK_CONST_FUNC:
case TK_FUNCTION: {
ExprList *pList = pExpr->pList;
int nExpr = pList ? pList->nExpr : 0;
FuncDef *pDef;
int nId;
const char *zId;
int constMask = 0;
int i;
u8 enc = ENC(db);
CollSeq *pColl = 0;
testcase( op==TK_CONST_FUNC );
testcase( op==TK_FUNCTION );
zId = (char*)pExpr->token.z;
nId = pExpr->token.n;
pDef = sqlite3FindFunction(db, zId, nId, nExpr, enc, 0);
assert( pDef!=0 );
if( pList ){
nExpr = pList->nExpr;
r1 = sqlite3GetTempRange(pParse, nExpr);
sqlite3ExprCodeExprList(pParse, pList, r1, 1);
}else{
nExpr = 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( nExpr>=2 && (pExpr->flags & EP_InfixFunc) ){
pDef = sqlite3VtabOverloadFunction(db, pDef, nExpr, pList->a[1].pExpr);
}else if( nExpr>0 ){
pDef = sqlite3VtabOverloadFunction(db, pDef, nExpr, pList->a[0].pExpr);
}
#endif
for(i=0; i<nExpr && i<32; i++){
if( sqlite3ExprIsConstant(pList->a[i].pExpr) ){
constMask |= (1<<i);
}
if( (pDef->flags & SQLITE_FUNC_NEEDCOLL)!=0 && !pColl ){
pColl = sqlite3ExprCollSeq(pParse, pList->a[i].pExpr);
}
}
if( pDef->flags & SQLITE_FUNC_NEEDCOLL ){
if( !pColl ) pColl = db->pDfltColl;
sqlite3VdbeAddOp4(v, OP_CollSeq, 0, 0, 0, (char *)pColl, P4_COLLSEQ);
}
sqlite3VdbeAddOp4(v, OP_Function, constMask, r1, target,
(char*)pDef, P4_FUNCDEF);
sqlite3VdbeChangeP5(v, nExpr);
if( nExpr ){
sqlite3ReleaseTempRange(pParse, r1, nExpr);
}
sqlite3ExprCacheAffinityChange(pParse, r1, nExpr);
break;
}
#ifndef SQLITE_OMIT_SUBQUERY
case TK_EXISTS:
case TK_SELECT: {
testcase( op==TK_EXISTS );
testcase( op==TK_SELECT );
if( pExpr->iColumn==0 ){
sqlite3CodeSubselect(pParse, pExpr, 0, 0);
}
inReg = pExpr->iColumn;
break;
}
case TK_IN: {
int rNotFound = 0;
int rMayHaveNull = 0;
int j2, j3, j4, j5;
char affinity;
int eType;
VdbeNoopComment((v, "begin IN expr r%d", target));
eType = sqlite3FindInIndex(pParse, pExpr, &rMayHaveNull);
if( rMayHaveNull ){
rNotFound = ++pParse->nMem;
}
/* Figure out the affinity to use to create a key from the results
** of the expression. affinityStr stores a static string suitable for
** P4 of OP_MakeRecord.
*/
affinity = comparisonAffinity(pExpr);
/* Code the <expr> from "<expr> IN (...)". The temporary table
** pExpr->iTable contains the values that make up the (...) set.
*/
pParse->disableColCache++;
sqlite3ExprCode(pParse, pExpr->pLeft, target);
pParse->disableColCache--;
j2 = sqlite3VdbeAddOp1(v, OP_IsNull, target);
if( eType==IN_INDEX_ROWID ){
j3 = sqlite3VdbeAddOp1(v, OP_MustBeInt, target);
j4 = sqlite3VdbeAddOp3(v, OP_NotExists, pExpr->iTable, 0, target);
sqlite3VdbeAddOp2(v, OP_Integer, 1, target);
j5 = sqlite3VdbeAddOp0(v, OP_Goto);
sqlite3VdbeJumpHere(v, j3);
sqlite3VdbeJumpHere(v, j4);
sqlite3VdbeAddOp2(v, OP_Integer, 0, target);
}else{
r2 = regFree2 = sqlite3GetTempReg(pParse);
/* Create a record and test for set membership. If the set contains
** the value, then jump to the end of the test code. The target
** register still contains the true (1) value written to it earlier.
*/
sqlite3VdbeAddOp4(v, OP_MakeRecord, target, 1, r2, &affinity, 1);
sqlite3VdbeAddOp2(v, OP_Integer, 1, target);
j5 = sqlite3VdbeAddOp3(v, OP_Found, pExpr->iTable, 0, r2);
/* If the set membership test fails, then the result of the
** "x IN (...)" expression must be either 0 or NULL. If the set
** contains no NULL values, then the result is 0. If the set
** contains one or more NULL values, then the result of the
** expression is also NULL.
*/
if( rNotFound==0 ){
/* This branch runs if it is known at compile time (now) that
** the set contains no NULL values. This happens as the result
** of a "NOT NULL" constraint in the database schema. No need
** to test the data structure at runtime in this case.
*/
sqlite3VdbeAddOp2(v, OP_Integer, 0, target);
}else{
/* This block populates the rNotFound register with either NULL
** or 0 (an integer value). If the data structure contains one
** or more NULLs, then set rNotFound to NULL. Otherwise, set it
** to 0. If register rMayHaveNull is already set to some value
** other than NULL, then the test has already been run and
** rNotFound is already populated.
*/
static const char nullRecord[] = { 0x02, 0x00 };
j3 = sqlite3VdbeAddOp1(v, OP_NotNull, rMayHaveNull);
sqlite3VdbeAddOp2(v, OP_Null, 0, rNotFound);
sqlite3VdbeAddOp4(v, OP_Blob, 2, rMayHaveNull, 0,
nullRecord, P4_STATIC);
j4 = sqlite3VdbeAddOp3(v, OP_Found, pExpr->iTable, 0, rMayHaveNull);
sqlite3VdbeAddOp2(v, OP_Integer, 0, rNotFound);
sqlite3VdbeJumpHere(v, j4);
sqlite3VdbeJumpHere(v, j3);
/* Copy the value of register rNotFound (which is either NULL or 0)
** into the target register. This will be the result of the
** expression.
*/
sqlite3VdbeAddOp2(v, OP_Copy, rNotFound, target);
}
}
sqlite3VdbeJumpHere(v, j2);
sqlite3VdbeJumpHere(v, j5);
VdbeComment((v, "end IN expr r%d", target));
break;
}
#endif
/*
** 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: {
Expr *pLeft = pExpr->pLeft;
struct ExprList_item *pLItem = pExpr->pList->a;
Expr *pRight = pLItem->pExpr;
codeCompareOperands(pParse, pLeft, &r1, ®Free1,
pRight, &r2, ®Free2);
testcase( regFree1==0 );
testcase( regFree2==0 );
r3 = sqlite3GetTempReg(pParse);
r4 = sqlite3GetTempReg(pParse);
codeCompare(pParse, pLeft, pRight, OP_Ge,
r1, r2, r3, SQLITE_STOREP2);
pLItem++;
pRight = pLItem->pExpr;
sqlite3ReleaseTempReg(pParse, regFree2);
r2 = sqlite3ExprCodeTemp(pParse, pRight, ®Free2);
testcase( regFree2==0 );
codeCompare(pParse, pLeft, pRight, OP_Le, r1, r2, r4, SQLITE_STOREP2);
sqlite3VdbeAddOp3(v, OP_And, r3, r4, target);
sqlite3ReleaseTempReg(pParse, r3);
sqlite3ReleaseTempReg(pParse, r4);
break;
}
case TK_UPLUS: {
inReg = sqlite3ExprCodeTarget(pParse, pExpr->pLeft, target);
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 pExpr->pRight. The Y is also optional. If there is no
** ELSE clause and no other term matches, then the result of the
** exprssion 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.
*/
case 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 cacheX; /* Cached expression X */
Expr *pX; /* The X expression */
Expr *pTest; /* X==Ei (form A) or just Ei (form B) */
assert(pExpr->pList);
assert((pExpr->pList->nExpr % 2) == 0);
assert(pExpr->pList->nExpr > 0);
pEList = pExpr->pList;
aListelem = pEList->a;
nExpr = pEList->nExpr;
endLabel = sqlite3VdbeMakeLabel(v);
if( (pX = pExpr->pLeft)!=0 ){
cacheX = *pX;
testcase( pX->op==TK_COLUMN || pX->op==TK_REGISTER );
cacheX.iTable = sqlite3ExprCodeTemp(pParse, pX, ®Free1);
testcase( regFree1==0 );
cacheX.op = TK_REGISTER;
opCompare.op = TK_EQ;
opCompare.pLeft = &cacheX;
pTest = &opCompare;
}
pParse->disableColCache++;
for(i=0; i<nExpr; i=i+2){
if( pX ){
opCompare.pRight = aListelem[i].pExpr;
}else{
pTest = aListelem[i].pExpr;
}
nextCase = sqlite3VdbeMakeLabel(v);
testcase( pTest->op==TK_COLUMN || pTest->op==TK_REGISTER );
sqlite3ExprIfFalse(pParse, pTest, nextCase, SQLITE_JUMPIFNULL);
testcase( aListelem[i+1].pExpr->op==TK_COLUMN );
testcase( aListelem[i+1].pExpr->op==TK_REGISTER );
sqlite3ExprCode(pParse, aListelem[i+1].pExpr, target);
sqlite3VdbeAddOp2(v, OP_Goto, 0, endLabel);
sqlite3VdbeResolveLabel(v, nextCase);
}
if( pExpr->pRight ){
sqlite3ExprCode(pParse, pExpr->pRight, target);
}else{
sqlite3VdbeAddOp2(v, OP_Null, 0, target);
}
sqlite3VdbeResolveLabel(v, endLabel);
assert( pParse->disableColCache>0 );
pParse->disableColCache--;
break;
}
#ifndef SQLITE_OMIT_TRIGGER
case TK_RAISE: {
if( !pParse->trigStack ){
sqlite3ErrorMsg(pParse,
"RAISE() may only be used within a trigger-program");
return 0;
}
if( pExpr->iColumn!=OE_Ignore ){
assert( pExpr->iColumn==OE_Rollback ||
pExpr->iColumn == OE_Abort ||
pExpr->iColumn == OE_Fail );
sqlite3DequoteExpr(db, pExpr);
sqlite3VdbeAddOp4(v, OP_Halt, SQLITE_CONSTRAINT, pExpr->iColumn, 0,
(char*)pExpr->token.z, pExpr->token.n);
} else {
assert( pExpr->iColumn == OE_Ignore );
sqlite3VdbeAddOp2(v, OP_ContextPop, 0, 0);
sqlite3VdbeAddOp2(v, OP_Goto, 0, pParse->trigStack->ignoreJump);
VdbeComment((v, "raise(IGNORE)"));
}
break;
}
#endif
}
sqlite3ReleaseTempReg(pParse, regFree1);
sqlite3ReleaseTempReg(pParse, regFree2);
return inReg;
}
/*
** 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.
*/
int sqlite3ExprCodeTemp(Parse *pParse, Expr *pExpr, int *pReg){
int r1 = sqlite3GetTempReg(pParse);
int 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.
*/
int sqlite3ExprCode(Parse *pParse, Expr *pExpr, int target){
int inReg;
assert( target>0 && target<=pParse->nMem );
inReg = sqlite3ExprCodeTarget(pParse, pExpr, target);
assert( pParse->pVdbe || pParse->db->mallocFailed );
if( inReg!=target && pParse->pVdbe ){
sqlite3VdbeAddOp2(pParse->pVdbe, OP_SCopy, inReg, target);
}
return target;
}
/*
** Generate code that evalutes 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.
*/
int sqlite3ExprCodeAndCache(Parse *pParse, Expr *pExpr, int target){
Vdbe *v = pParse->pVdbe;
int inReg;
inReg = sqlite3ExprCode(pParse, pExpr, target);
assert( target>0 );
if( pExpr->op!=TK_REGISTER ){
int iMem;
iMem = ++pParse->nMem;
sqlite3VdbeAddOp2(v, OP_Copy, inReg, iMem);
pExpr->iTable = iMem;
pExpr->op = TK_REGISTER;
}
return inReg;
}
/*
** Return TRUE if pExpr is an constant expression that is appropriate
** for factoring out of a loop. Appropriate expressions are:
**
** * Any expression that evaluates to two or more opcodes.
**
** * Any OP_Integer, OP_Real, OP_String, OP_Blob, OP_Null,
** or OP_Variable that does not need to be placed in a
** specific register.
**
** There is no point in factoring out single-instruction constant
** expressions that need to be placed in a particular register.
** We could factor them out, but then we would end up adding an
** OP_SCopy instruction to move the value into the correct register
** later. We might as well just use the original instruction and
** avoid the OP_SCopy.
*/
static int isAppropriateForFactoring(Expr *p){
if( !sqlite3ExprIsConstantNotJoin(p) ){
return 0; /* Only constant expressions are appropriate for factoring */
}
if( (p->flags & EP_FixedDest)==0 ){
return 1; /* Any constant without a fixed destination is appropriate */
}
while( p->op==TK_UPLUS ) p = p->pLeft;
switch( p->op ){
#ifndef SQLITE_OMIT_BLOB_LITERAL
case TK_BLOB:
#endif
case TK_VARIABLE:
case TK_INTEGER:
case TK_FLOAT:
case TK_NULL:
case TK_STRING: {
testcase( p->op==TK_BLOB );
testcase( p->op==TK_VARIABLE );
testcase( p->op==TK_INTEGER );
testcase( p->op==TK_FLOAT );
testcase( p->op==TK_NULL );
testcase( p->op==TK_STRING );
/* Single-instruction constants with a fixed destination are
** better done in-line. If we factor them, they will just end
** up generating an OP_SCopy to move the value to the destination
** register. */
return 0;
}
case TK_UMINUS: {
if( p->pLeft->op==TK_FLOAT || p->pLeft->op==TK_INTEGER ){
return 0;
}
break;
}
default: {
break;
}
}
return 1;
}
/*
** If pExpr is a constant expression that is appropriate for
** factoring out of a loop, then evaluate the expression
** into a register and convert the expression into a TK_REGISTER
** expression.
*/
static int evalConstExpr(Walker *pWalker, Expr *pExpr){
Parse *pParse = pWalker->pParse;
switch( pExpr->op ){
case TK_REGISTER: {
return 1;
}
case TK_FUNCTION:
case TK_AGG_FUNCTION:
case TK_CONST_FUNC: {
/* The arguments to a function have a fixed destination.
** Mark them this way to avoid generated unneeded OP_SCopy
** instructions.
*/
ExprList *pList = pExpr->pList;
if( pList ){
int i = pList->nExpr;
struct ExprList_item *pItem = pList->a;
for(; i>0; i--, pItem++){
if( pItem->pExpr ) pItem->pExpr->flags |= EP_FixedDest;
}
}
break;
}
}
if( isAppropriateForFactoring(pExpr) ){
int r1 = ++pParse->nMem;
int r2;
r2 = sqlite3ExprCodeTarget(pParse, pExpr, r1);
if( r1!=r2 ) sqlite3ReleaseTempReg(pParse, r1);
pExpr->op = TK_REGISTER;
pExpr->iTable = r2;
return WRC_Prune;
}
return WRC_Continue;
}
/*
** Preevaluate constant subexpressions within pExpr and store the
** results in registers. Modify pExpr so that the constant subexpresions
** are TK_REGISTER opcodes that refer to the precomputed values.
*/
void sqlite3ExprCodeConstants(Parse *pParse, Expr *pExpr){
Walker w;
w.xExprCallback = evalConstExpr;
w.xSelectCallback = 0;
w.pParse = pParse;
sqlite3WalkExpr(&w, pExpr);
}
/*
** 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.
*/
int sqlite3ExprCodeExprList(
Parse *pParse, /* Parsing context */
ExprList *pList, /* The expression list to be coded */
int target, /* Where to write results */
int doHardCopy /* Make a hard copy of every element */
){
struct ExprList_item *pItem;
int i, n;
assert( pList!=0 );
assert( target>0 );
n = pList->nExpr;
for(pItem=pList->a, i=0; i<n; i++, pItem++){
if( pItem->iAlias ){
int iReg = codeAlias(pParse, pItem->iAlias, pItem->pExpr, target);
Vdbe *v = sqlite3GetVdbe(pParse);
if( iReg!=target+i ){
sqlite3VdbeAddOp2(v, OP_SCopy, iReg, target+i);
}
}else{
sqlite3ExprCode(pParse, pItem->pExpr, target+i);
}
if( doHardCopy ){
sqlite3ExprHardCopy(pParse, target, n);
}
}
return n;
}
/*
** 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( v==0 || pExpr==0 ) return;
op = pExpr->op;
switch( op ){
case TK_AND: {
int d2 = sqlite3VdbeMakeLabel(v);
testcase( jumpIfNull==0 );
testcase( pParse->disableColCache==0 );
sqlite3ExprIfFalse(pParse, pExpr->pLeft, d2,jumpIfNull^SQLITE_JUMPIFNULL);
pParse->disableColCache++;
sqlite3ExprIfTrue(pParse, pExpr->pRight, dest, jumpIfNull);
assert( pParse->disableColCache>0 );
pParse->disableColCache--;
sqlite3VdbeResolveLabel(v, d2);
break;
}
case TK_OR: {
testcase( jumpIfNull==0 );
testcase( pParse->disableColCache==0 );
sqlite3ExprIfTrue(pParse, pExpr->pLeft, dest, jumpIfNull);
pParse->disableColCache++;
sqlite3ExprIfTrue(pParse, pExpr->pRight, dest, jumpIfNull);
assert( pParse->disableColCache>0 );
pParse->disableColCache--;
break;
}
case TK_NOT: {
testcase( jumpIfNull==0 );
sqlite3ExprIfFalse(pParse, pExpr->pLeft, dest, jumpIfNull);
break;
}
case TK_LT:
case TK_LE:
case TK_GT:
case TK_GE:
case TK_NE:
case TK_EQ: {
assert( TK_LT==OP_Lt );
assert( TK_LE==OP_Le );
assert( TK_GT==OP_Gt );
assert( TK_GE==OP_Ge );
assert( TK_EQ==OP_Eq );
assert( TK_NE==OP_Ne );
testcase( op==TK_LT );
testcase( op==TK_LE );
testcase( op==TK_GT );
testcase( op==TK_GE );
testcase( op==TK_EQ );
testcase( op==TK_NE );
testcase( jumpIfNull==0 );
codeCompareOperands(pParse, pExpr->pLeft, &r1, ®Free1,
pExpr->pRight, &r2, ®Free2);
codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op,
r1, r2, dest, jumpIfNull);
testcase( regFree1==0 );
testcase( regFree2==0 );
break;
}
case TK_ISNULL:
case TK_NOTNULL: {
assert( TK_ISNULL==OP_IsNull );
assert( TK_NOTNULL==OP_NotNull );
testcase( op==TK_ISNULL );
testcase( op==TK_NOTNULL );
r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1);
sqlite3VdbeAddOp2(v, op, r1, dest);
testcase( regFree1==0 );
break;
}
case TK_BETWEEN: {
/* x BETWEEN y AND z
**
** Is equivalent to
**
** x>=y AND x<=z
**
** Code it as such, taking care to do the common subexpression
** elementation of x.
*/
Expr exprAnd;
Expr compLeft;
Expr compRight;
Expr exprX;
exprX = *pExpr->pLeft;
exprAnd.op = TK_AND;
exprAnd.pLeft = &compLeft;
exprAnd.pRight = &compRight;
compLeft.op = TK_GE;
compLeft.pLeft = &exprX;
compLeft.pRight = pExpr->pList->a[0].pExpr;
compRight.op = TK_LE;
compRight.pLeft = &exprX;
compRight.pRight = pExpr->pList->a[1].pExpr;
exprX.iTable = sqlite3ExprCodeTemp(pParse, &exprX, ®Free1);
testcase( regFree1==0 );
exprX.op = TK_REGISTER;
testcase( jumpIfNull==0 );
sqlite3ExprIfTrue(pParse, &exprAnd, dest, jumpIfNull);
break;
}
default: {
r1 = sqlite3ExprCodeTemp(pParse, pExpr, ®Free1);
sqlite3VdbeAddOp3(v, OP_If, r1, dest, jumpIfNull!=0);
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( v==0 || 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 );
testcase( pParse->disableColCache==0 );
sqlite3ExprIfFalse(pParse, pExpr->pLeft, dest, jumpIfNull);
pParse->disableColCache++;
sqlite3ExprIfFalse(pParse, pExpr->pRight, dest, jumpIfNull);
assert( pParse->disableColCache>0 );
pParse->disableColCache--;
break;
}
case TK_OR: {
int d2 = sqlite3VdbeMakeLabel(v);
testcase( jumpIfNull==0 );
testcase( pParse->disableColCache==0 );
sqlite3ExprIfTrue(pParse, pExpr->pLeft, d2, jumpIfNull^SQLITE_JUMPIFNULL);
pParse->disableColCache++;
sqlite3ExprIfFalse(pParse, pExpr->pRight, dest, jumpIfNull);
assert( pParse->disableColCache>0 );
pParse->disableColCache--;
sqlite3VdbeResolveLabel(v, d2);
break;
}
case TK_NOT: {
sqlite3ExprIfTrue(pParse, pExpr->pLeft, dest, jumpIfNull);
break;
}
case TK_LT:
case TK_LE:
case TK_GT:
case TK_GE:
case TK_NE:
case TK_EQ: {
testcase( op==TK_LT );
testcase( op==TK_LE );
testcase( op==TK_GT );
testcase( op==TK_GE );
testcase( op==TK_EQ );
testcase( op==TK_NE );
testcase( jumpIfNull==0 );
codeCompareOperands(pParse, pExpr->pLeft, &r1, ®Free1,
pExpr->pRight, &r2, ®Free2);
codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op,
r1, r2, dest, jumpIfNull);
testcase( regFree1==0 );
testcase( regFree2==0 );
break;
}
case TK_ISNULL:
case TK_NOTNULL: {
testcase( op==TK_ISNULL );
testcase( op==TK_NOTNULL );
r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1);
sqlite3VdbeAddOp2(v, op, r1, dest);
testcase( regFree1==0 );
break;
}
case TK_BETWEEN: {
/* x BETWEEN y AND z
**
** Is equivalent to
**
** x>=y AND x<=z
**
** Code it as such, taking care to do the common subexpression
** elementation of x.
*/
Expr exprAnd;
Expr compLeft;
Expr compRight;
Expr exprX;
exprX = *pExpr->pLeft;
exprAnd.op = TK_AND;
exprAnd.pLeft = &compLeft;
exprAnd.pRight = &compRight;
compLeft.op = TK_GE;
compLeft.pLeft = &exprX;
compLeft.pRight = pExpr->pList->a[0].pExpr;
compRight.op = TK_LE;
compRight.pLeft = &exprX;
compRight.pRight = pExpr->pList->a[1].pExpr;
exprX.iTable = sqlite3ExprCodeTemp(pParse, &exprX, ®Free1);
testcase( regFree1==0 );
exprX.op = TK_REGISTER;
testcase( jumpIfNull==0 );
sqlite3ExprIfFalse(pParse, &exprAnd, dest, jumpIfNull);
break;
}
default: {
r1 = sqlite3ExprCodeTemp(pParse, pExpr, ®Free1);
sqlite3VdbeAddOp3(v, OP_IfNot, r1, dest, jumpIfNull!=0);
testcase( regFree1==0 );
testcase( jumpIfNull==0 );
break;
}
}
sqlite3ReleaseTempReg(pParse, regFree1);
sqlite3ReleaseTempReg(pParse, regFree2);
}
/*
** Do a deep comparison of two expression trees. Return TRUE (non-zero)
** if they are identical and return FALSE if they differ in any way.
**
** Sometimes this routine will return FALSE even if the two expressions
** really are equivalent. If we cannot prove that the expressions are
** identical, we return FALSE just to be safe. So if this routine
** returns false, then you do not really know for certain if the two
** expressions are the same. But if you get a TRUE 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 FALSE - that
** just might result in some slightly slower code. But returning
** an incorrect TRUE could lead to a malfunction.
*/
int sqlite3ExprCompare(Expr *pA, Expr *pB){
int i;
if( pA==0||pB==0 ){
return pB==pA;
}
if( pA->op!=pB->op ) return 0;
if( (pA->flags & EP_Distinct)!=(pB->flags & EP_Distinct) ) return 0;
if( !sqlite3ExprCompare(pA->pLeft, pB->pLeft) ) return 0;
if( !sqlite3ExprCompare(pA->pRight, pB->pRight) ) return 0;
if( pA->pList ){
if( pB->pList==0 ) return 0;
if( pA->pList->nExpr!=pB->pList->nExpr ) return 0;
for(i=0; i<pA->pList->nExpr; i++){
if( !sqlite3ExprCompare(pA->pList->a[i].pExpr, pB->pList->a[i].pExpr) ){
return 0;
}
}
}else if( pB->pList ){
return 0;
}
if( pA->pSelect || pB->pSelect ) return 0;
if( pA->iTable!=pB->iTable || pA->iColumn!=pB->iColumn ) return 0;
if( pA->op!=TK_COLUMN && pA->token.z ){
if( pB->token.z==0 ) return 0;
if( pB->token.n!=pA->token.n ) return 0;
if( sqlite3StrNICmp((char*)pA->token.z,(char*)pB->token.z,pB->token.n)!=0 ){
return 0;
}
}
return 1;
}
/*
** 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]),
3,
&pInfo->nColumn,
&pInfo->nColumnAlloc,
&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]),
3,
&pInfo->nFunc,
&pInfo->nFuncAlloc,
&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->pAggInfo;
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( pSrcList ){
struct SrcList_item *pItem = pSrcList->a;
for(i=0; i<pSrcList->nSrc; i++, pItem++){
struct AggInfo_col *pCol;
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.
*/
pExpr->pAggInfo = pAggInfo;
pExpr->op = TK_AGG_COLUMN;
pExpr->iAgg = k;
break;
} /* endif pExpr->iTable==pItem->iCursor */
} /* end loop over pSrcList */
}
return WRC_Prune;
}
case TK_AGG_FUNCTION: {
/* The pNC->nDepth==0 test causes aggregate functions in subqueries
** to be ignored */
if( pNC->nDepth==0 ){
/* 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(pItem->pExpr, pExpr) ){
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 ){
pItem = &pAggInfo->aFunc[i];
pItem->pExpr = pExpr;
pItem->iMem = ++pParse->nMem;
pItem->pFunc = sqlite3FindFunction(pParse->db,
(char*)pExpr->token.z, pExpr->token.n,
pExpr->pList ? pExpr->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
*/
pExpr->iAgg = i;
pExpr->pAggInfo = pAggInfo;
return WRC_Prune;
}
}
}
return WRC_Continue;
}
static int analyzeAggregatesInSelect(Walker *pWalker, Select *pSelect){
NameContext *pNC = pWalker->u.pNC;
if( pNC->nDepth==0 ){
pNC->nDepth++;
sqlite3WalkSelect(pWalker, pSelect);
pNC->nDepth--;
return WRC_Prune;
}else{
return WRC_Continue;
}
}
/*
** Analyze the given expression looking for aggregate functions and
** for variables that need to be added to the pParse->aAgg[] array.
** Make additional entries to the pParse->aAgg[] array 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.u.pNC = pNC;
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 or deallocate temporary use registers during code generation.
*/
int sqlite3GetTempReg(Parse *pParse){
if( pParse->nTempReg==0 ){
return ++pParse->nMem;
}
return pParse->aTempReg[--pParse->nTempReg];
}
void sqlite3ReleaseTempReg(Parse *pParse, int iReg){
if( iReg && pParse->nTempReg<ArraySize(pParse->aTempReg) ){
sqlite3ExprWritableRegister(pParse, iReg, iReg);
pParse->aTempReg[pParse->nTempReg++] = iReg;
}
}
/*
** Allocate or deallocate a block of nReg consecutive registers
*/
int sqlite3GetTempRange(Parse *pParse, int nReg){
int i, n;
i = pParse->iRangeReg;
n = pParse->nRangeReg;
if( nReg<=n && !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>pParse->nRangeReg ){
pParse->nRangeReg = nReg;
pParse->iRangeReg = iReg;
}
}