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Do not reuse factored constants that might have had their encodings changed.

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FossilOrigin-Name: 487f20366ce77f0c90865d10d5aaedd95af98694
This commit is contained in:
drh
2013-11-21 21:23:31 +00:00
parent d9f158e7b2
commit d673cddad6
5 changed files with 61 additions and 16 deletions
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24
src/expr.c
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@@ -2989,13 +2989,22 @@ int sqlite3ExprCodeTarget(Parse *pParse, Expr *pExpr, int target){
/*
** Factor out the code of the given expression to initialization time.
*/
void sqlite3ExprCodeAtInit(Parse *pParse, Expr *pExpr, int regDest){
void sqlite3ExprCodeAtInit(
Parse *pParse, /* Parsing context */
Expr *pExpr, /* The expression to code when the VDBE initializes */
int regDest, /* Store the value in this register */
u8 reusable /* True if this expression is reusable */
){
ExprList *p;
assert( ConstFactorOk(pParse) );
p = pParse->pConstExpr;
pExpr = sqlite3ExprDup(pParse->db, pExpr, 0);
p = sqlite3ExprListAppend(pParse, p, pExpr);
if( p ) p->a[p->nExpr-1].u.iConstExprReg = regDest;
if( p ){
struct ExprList_item *pItem = &p->a[p->nExpr-1];
pItem->u.iConstExprReg = regDest;
pItem->reusable = reusable;
}
pParse->pConstExpr = p;
}
@@ -3023,14 +3032,15 @@ int sqlite3ExprCodeTemp(Parse *pParse, Expr *pExpr, int *pReg){
int i;
*pReg = 0;
if( p ){
for(i=0; i<p->nExpr; i++){
if( sqlite3ExprCompare(p->a[i].pExpr, pExpr, -1)==0 ){
return p->a[i].u.iConstExprReg;
struct ExprList_item *pItem;
for(pItem=p->a, i=p->nExpr; i>0; pItem++, i--){
if( pItem->reusable && sqlite3ExprCompare(pItem->pExpr,pExpr,-1)==0 ){
return pItem->u.iConstExprReg;
}
}
}
r2 = ++pParse->nMem;
sqlite3ExprCodeAtInit(pParse, pExpr, r2);
sqlite3ExprCodeAtInit(pParse, pExpr, r2, 1);
}else{
int r1 = sqlite3GetTempReg(pParse);
r2 = sqlite3ExprCodeTarget(pParse, pExpr, r1);
@@ -3399,7 +3409,7 @@ int sqlite3ExprCodeExprList(
for(pItem=pList->a, i=0; i<n; i++, pItem++){
Expr *pExpr = pItem->pExpr;
if( (flags & SQLITE_ECEL_FACTOR)!=0 && sqlite3ExprIsConstant(pExpr) ){
sqlite3ExprCodeAtInit(pParse, pExpr, target+i);
sqlite3ExprCodeAtInit(pParse, pExpr, target+i, 0);
}else{
int inReg = sqlite3ExprCodeTarget(pParse, pExpr, target+i);
if( inReg!=target+i ){