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| author | drh <drh@noemail.net> | 2011-09-16 01:34:43 +0000 |
|---|---|---|
| committer | drh <drh@noemail.net> | 2011-09-16 01:34:43 +0000 |
| commit | 48f2d3b10a5ac48ae2a1a24f77c7cb1aab6ea978 (patch) | |
| tree | 0b02d36b1ecb60c458133c090c14df3c131b6151 /src/select.c | |
| parent | 5b6a9ed49556deac6d48be80b6ef2816102f1951 (diff) | |
| download | sqlite-48f2d3b10a5ac48ae2a1a24f77c7cb1aab6ea978.tar.gz sqlite-48f2d3b10a5ac48ae2a1a24f77c7cb1aab6ea978.zip | |
Add the new OP_Once opcode. Use it to clean up and simplify various
one-time initialization sections in the code, including the fix for
ticket [002caede898ae].
FossilOrigin-Name: 7f00552b739fad79517b042a6ed61abe743a917b
Diffstat (limited to 'src/select.c')
| -rw-r--r-- | src/select.c | 13 |
1 files changed, 6 insertions, 7 deletions
diff --git a/src/select.c b/src/select.c index 2ddc751b5..277f5c026 100644 --- a/src/select.c +++ b/src/select.c @@ -3831,7 +3831,7 @@ int sqlite3Select( ** is a register allocated to hold the subroutine return address */ int topAddr = sqlite3VdbeAddOp0(v, OP_Goto); - int regOnce = 0; + int onceAddr = 0; assert( pItem->addrFillSub==0 ); pItem->addrFillSub = topAddr+1; pItem->regReturn = ++pParse->nMem; @@ -3839,15 +3839,14 @@ int sqlite3Select( /* If the subquery is no correlated and if we are not inside of ** a trigger, then we only need to compute the value of the subquery ** once. */ - regOnce = ++pParse->nMem; - sqlite3VdbeAddOp1(v, OP_If, regOnce); - sqlite3VdbeAddOp2(v, OP_Integer, 1, regOnce); + int regOnce = ++pParse->nMem; + onceAddr = sqlite3VdbeAddOp1(v, OP_Once, regOnce); } sqlite3SelectDestInit(&dest, SRT_EphemTab, pItem->iCursor); explainSetInteger(pItem->iSelectId, (u8)pParse->iNextSelectId); sqlite3Select(pParse, pSub, &dest); pItem->pTab->nRowEst = (unsigned)pSub->nSelectRow; - if( regOnce ) sqlite3VdbeJumpHere(v, topAddr+1); + if( onceAddr ) sqlite3VdbeJumpHere(v, onceAddr); sqlite3VdbeAddOp1(v, OP_Return, pItem->regReturn); sqlite3VdbeJumpHere(v, topAddr); sqlite3VdbeAddOp2(v, OP_Gosub, pItem->regReturn, topAddr+1); @@ -3991,7 +3990,7 @@ int sqlite3Select( ** into an OP_Noop. */ if( addrSortIndex>=0 && pOrderBy==0 ){ - sqlite3VdbeChangeToNoop(v, addrSortIndex, 1); + sqlite3VdbeChangeToNoop(v, addrSortIndex); p->addrOpenEphm[2] = -1; } @@ -4274,7 +4273,7 @@ int sqlite3Select( sqlite3VdbeAddOp2(v, OP_SorterNext, sAggInfo.sortingIdx, addrTopOfLoop); }else{ sqlite3WhereEnd(pWInfo); - sqlite3VdbeChangeToNoop(v, addrSortingIdx, 1); + sqlite3VdbeChangeToNoop(v, addrSortingIdx); } /* Output the final row of result |