Refactor the SrcItem object so that information about subqueries is stored

in a separately allocated Subquery object.  This reduces the memory requirements
for SrcItem and makes the code run faster.  It also provides an expansion path
for subquery processing that does not burden simple queries.  The current
checking mostly works, but there are still issues that need to be tracked
down and fixed.

FossilOrigin-Name: 8ff5dda8448d7e1a533d7f27db2573ce68fa9956b9d9847ced45e83c1f06bab0

1 files changed, 15 insertions, 5 deletions

diff --git a/src/wherecode.c b/src/wherecode.c
index ebc71d110..b0c0d9aed 100644
--- a/src/wherecode.c
+++ b/src/wherecode.c
@@ -317,7 +317,9 @@ void sqlite3WhereAddScanStatus(
         sqlite3VdbeScanStatusRange(v, addrExplain, -1, pLvl->iIdxCur);
       }
     }else{
-      int addr = pSrclist->a[pLvl->iFrom].sq.addrFillSub;
+      int addr;
+      assert( pSrclist->a[pLvl->iFrom].fg.isSubquery );
+      addr = pSrclist->a[pLvl->iFrom].u4.pSubq->addrFillSub;
       VdbeOp *pOp = sqlite3VdbeGetOp(v, addr-1);
       assert( sqlite3VdbeDb(v)->mallocFailed || pOp->opcode==OP_InitCoroutine );
       assert( sqlite3VdbeDb(v)->mallocFailed || pOp->p2>addr );
@@ -1510,8 +1512,12 @@ Bitmask sqlite3WhereCodeOneLoopStart(
 
   /* Special case of a FROM clause subquery implemented as a co-routine */
   if( pTabItem->fg.viaCoroutine ){
-    int regYield = pTabItem->sq.regReturn;
-    sqlite3VdbeAddOp3(v, OP_InitCoroutine, regYield,0,pTabItem->sq.addrFillSub);
+    int regYield;
+    Subquery *pSubq;
+    assert( pTabItem->fg.isSubquery && pTabItem->u4.pSubq!=0 );
+    pSubq = pTabItem->u4.pSubq;
+    regYield = pSubq->regReturn;
+    sqlite3VdbeAddOp3(v, OP_InitCoroutine, regYield, 0, pSubq->addrFillSub);
     pLevel->p2 =  sqlite3VdbeAddOp2(v, OP_Yield, regYield, addrBrk);
     VdbeCoverage(v);
     VdbeComment((v, "next row of %s", pTabItem->pSTab->zName));
@@ -2819,9 +2825,13 @@ SQLITE_NOINLINE void sqlite3WhereRightJoinLoop(
     pRight = &pWInfo->pTabList->a[pWInfo->a[k].iFrom];
     mAll |= pWInfo->a[k].pWLoop->maskSelf;
     if( pRight->fg.viaCoroutine ){
+      Subquery *pSubq;
+      assert( pRight->fg.isSubquery && pRight->u4.pSubq!=0 );
+      pSubq = pRight->u4.pSubq;
+      assert( pSubq->pSelect!=0 && pSubq->pSelect->pEList!=0 );
       sqlite3VdbeAddOp3(
-          v, OP_Null, 0, pRight->sq.regResult, 
-          pRight->sq.regResult + pRight->sq.pSelect->pEList->nExpr-1
+          v, OP_Null, 0, pSubq->regResult, 
+          pSubq->regResult + pSubq->pSelect->pEList->nExpr-1
       );
     }
     sqlite3VdbeAddOp1(v, OP_NullRow, pWInfo->a[k].iTabCur);