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Reduce the size of the stack required by the codeOneLoopStart() function in

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where.c.

FossilOrigin-Name: eb6d4278b8516e0571269049d1eaa55066f51b1a
This commit is contained in:
drh
2013-07-30 15:10:32 +00:00
parent f67feefffc
commit 6b36e82c7b
3 changed files with 27 additions and 22 deletions
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33
src/where.c
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@@ -3250,6 +3250,7 @@ static Bitmask codeOneLoopStart(
WhereClause *pWC; /* Decomposition of the entire WHERE clause */
WhereTerm *pTerm; /* A WHERE clause term */
Parse *pParse; /* Parsing context */
sqlite3 *db; /* Database connection */
Vdbe *v; /* The prepared stmt under constructions */
struct SrcList_item *pTabItem; /* FROM clause term being coded */
int addrBrk; /* Jump here to break out of the loop */
@@ -3261,6 +3262,7 @@ static Bitmask codeOneLoopStart(
pParse = pWInfo->pParse;
v = pParse->pVdbe;
pWC = &pWInfo->sWC;
db = pParse->db;
pLevel = &pWInfo->a[iLevel];
pLoop = pLevel->pWLoop;
pTabItem = &pWInfo->pTabList->a[pLevel->iFrom];
@@ -3551,7 +3553,7 @@ static Bitmask codeOneLoopStart(
** starting at regBase.
*/
regBase = codeAllEqualityTerms(pParse,pLevel,bRev,nExtraReg,&zStartAff);
zEndAff = sqlite3DbStrDup(pParse->db, zStartAff);
zEndAff = sqlite3DbStrDup(db, zStartAff);
addrNxt = pLevel->addrNxt;
/* If we are doing a reverse order scan on an ascending index, or
@@ -3636,8 +3638,8 @@ static Bitmask codeOneLoopStart(
nConstraint++;
testcase( pRangeEnd->wtFlags & TERM_VIRTUAL ); /* EV: R-30575-11662 */
}
sqlite3DbFree(pParse->db, zStartAff);
sqlite3DbFree(pParse->db, zEndAff);
sqlite3DbFree(db, zStartAff);
sqlite3DbFree(db, zEndAff);
/* Top of the loop body */
pLevel->p2 = sqlite3VdbeCurrentAddr(v);
@@ -3764,7 +3766,7 @@ static Bitmask codeOneLoopStart(
int nNotReady; /* The number of notReady tables */
struct SrcList_item *origSrc; /* Original list of tables */
nNotReady = pWInfo->nLevel - iLevel - 1;
pOrTab = sqlite3StackAllocRaw(pParse->db,
pOrTab = sqlite3StackAllocRaw(db,
sizeof(*pOrTab)+ nNotReady*sizeof(pOrTab->a[0]));
if( pOrTab==0 ) return notReady;
pOrTab->nAlloc = (u8)(nNotReady + 1);
@@ -3818,8 +3820,8 @@ static Bitmask codeOneLoopStart(
if( ExprHasProperty(pExpr, EP_FromJoin) ) continue;
if( pWC->a[iTerm].wtFlags & (TERM_ORINFO) ) continue;
if( (pWC->a[iTerm].eOperator & WO_ALL)==0 ) continue;
pExpr = sqlite3ExprDup(pParse->db, pExpr, 0);
pAndExpr = sqlite3ExprAnd(pParse->db, pAndExpr, pExpr);
pExpr = sqlite3ExprDup(db, pExpr, 0);
pAndExpr = sqlite3ExprAnd(db, pAndExpr, pExpr);
}
if( pAndExpr ){
pAndExpr = sqlite3PExpr(pParse, TK_AND, 0, pAndExpr, 0);
@@ -3839,7 +3841,7 @@ static Bitmask codeOneLoopStart(
pSubWInfo = sqlite3WhereBegin(pParse, pOrTab, pOrExpr, 0, 0,
WHERE_OMIT_OPEN_CLOSE | WHERE_AND_ONLY |
WHERE_FORCE_TABLE | WHERE_ONETABLE_ONLY, iCovCur);
assert( pSubWInfo || pParse->nErr || pParse->db->mallocFailed );
assert( pSubWInfo || pParse->nErr || db->mallocFailed );
if( pSubWInfo ){
WhereLoop *pSubLoop;
explainOneScan(
@@ -3894,13 +3896,13 @@ static Bitmask codeOneLoopStart(
if( pCov ) pLevel->iIdxCur = iCovCur;
if( pAndExpr ){
pAndExpr->pLeft = 0;
sqlite3ExprDelete(pParse->db, pAndExpr);
sqlite3ExprDelete(db, pAndExpr);
}
sqlite3VdbeChangeP1(v, iRetInit, sqlite3VdbeCurrentAddr(v));
sqlite3VdbeAddOp2(v, OP_Goto, 0, pLevel->addrBrk);
sqlite3VdbeResolveLabel(v, iLoopBody);
if( pWInfo->nLevel>1 ) sqlite3StackFree(pParse->db, pOrTab);
if( pWInfo->nLevel>1 ) sqlite3StackFree(db, pOrTab);
if( !untestedTerms ) disableTerm(pLevel, pTerm);
}else
#endif /* SQLITE_OMIT_OR_OPTIMIZATION */
@@ -3955,9 +3957,8 @@ static Bitmask codeOneLoopStart(
** the implied "t1.a=123" constraint.
*/
for(pTerm=pWC->a, j=pWC->nTerm; j>0; j--, pTerm++){
Expr *pE;
Expr *pE, *pEAlt;
WhereTerm *pAlt;
Expr sEq;
if( pTerm->wtFlags & (TERM_VIRTUAL|TERM_CODED) ) continue;
if( pTerm->eOperator!=(WO_EQUIV|WO_EQ) ) continue;
if( pTerm->leftCursor!=iCur ) continue;
@@ -3971,9 +3972,13 @@ static Bitmask codeOneLoopStart(
testcase( pAlt->eOperator & WO_EQ );
testcase( pAlt->eOperator & WO_IN );
VdbeNoopComment((v, "begin transitive constraint"));
sEq = *pAlt->pExpr;
sEq.pLeft = pE->pLeft;
sqlite3ExprIfFalse(pParse, &sEq, addrCont, SQLITE_JUMPIFNULL);
pEAlt = sqlite3StackAllocRaw(db, sizeof(*pEAlt));
if( pEAlt ){
*pEAlt = *pAlt->pExpr;
pEAlt->pLeft = pE->pLeft;
sqlite3ExprIfFalse(pParse, pEAlt, addrCont, SQLITE_JUMPIFNULL);
sqlite3StackFree(db, pEAlt);
}
}
/* For a LEFT OUTER JOIN, generate code that will record the fact that