Make sure the KeyInfo.aSortOrder array is always allocated so that we never

have to test for KeyInfo.aSortOrder==0 in performance-critical loops.

FossilOrigin-Name: 45793f0b844fee7445bc9269b403f89a58f77150

3 files changed, 12 insertions, 6 deletions

diff --git a/src/expr.c b/src/expr.c
index 89172f94b..3fb51cf11 100644
--- a/src/expr.c
+++ b/src/expr.c
@@ -1662,6 +1662,7 @@ int sqlite3CodeSubselect(
     case TK_IN: {
       char affinity;              /* Affinity of the LHS of the IN */
       KeyInfo keyInfo;            /* Keyinfo for the generated table */
+      static u8 sortOrder = 0;    /* Fake aSortOrder for keyInfo */
       int addr;                   /* Address of OP_OpenEphemeral instruction */
       Expr *pLeft = pExpr->pLeft; /* the LHS of the IN operator */
 
@@ -1689,6 +1690,7 @@ int sqlite3CodeSubselect(
       if( rMayHaveNull==0 ) sqlite3VdbeChangeP5(v, BTREE_UNORDERED);
       memset(&keyInfo, 0, sizeof(keyInfo));
       keyInfo.nField = 1;
+      keyInfo.aSortOrder = &sortOrder;
 
       if( ExprHasProperty(pExpr, EP_xIsSelect) ){
         /* Case 1:     expr IN (SELECT ...)
@@ -1729,6 +1731,7 @@ int sqlite3CodeSubselect(
           affinity = SQLITE_AFF_NONE;
         }
         keyInfo.aColl[0] = sqlite3ExprCollSeq(pParse, pExpr->pLeft);
+        keyInfo.aSortOrder = &sortOrder;
 
         /* Loop through each expression in <exprlist>. */
         r1 = sqlite3GetTempReg(pParse);
diff --git a/src/select.c b/src/select.c
index 0bf47e852..656f39d6e 100644
--- a/src/select.c
+++ b/src/select.c
@@ -1892,6 +1892,7 @@ static int multiSelect(
         *apColl = db->pDfltColl;
       }
     }
+    pKeyInfo->aSortOrder = (u8*)apColl;
 
     for(pLoop=p; pLoop; pLoop=pLoop->pPrior){
       for(i=0; i<2; i++){
diff --git a/src/vdbeaux.c b/src/vdbeaux.c
index dd23d395b..9db3bf435 100644
--- a/src/vdbeaux.c
+++ b/src/vdbeaux.c
@@ -745,10 +745,9 @@ void sqlite3VdbeChangeP4(Vdbe *p, int addr, const char *zP4, int n){
       u8 *aSortOrder;
       memcpy((char*)pKeyInfo, zP4, nByte - nField);
       aSortOrder = pKeyInfo->aSortOrder;
-      if( aSortOrder ){
-        pKeyInfo->aSortOrder = (unsigned char*)&pKeyInfo->aColl[nField];
-        memcpy(pKeyInfo->aSortOrder, aSortOrder, nField);
-      }
+      assert( aSortOrder!=0 );
+      pKeyInfo->aSortOrder = (unsigned char*)&pKeyInfo->aColl[nField];
+      memcpy(pKeyInfo->aSortOrder, aSortOrder, nField);
       pOp->p4type = P4_KEYINFO;
     }else{
       p->db->mallocFailed = 1;
@@ -861,6 +860,7 @@ static char *displayP4(Op *pOp, char *zTemp, int nTemp){
     case P4_KEYINFO: {
       int i, j;
       KeyInfo *pKeyInfo = pOp->p4.pKeyInfo;
+      assert( pKeyInfo->aSortOrder!=0 );
       sqlite3_snprintf(nTemp, zTemp, "keyinfo(%d", pKeyInfo->nField);
       i = sqlite3Strlen30(zTemp);
       for(j=0; j<pKeyInfo->nField; j++){
@@ -872,7 +872,7 @@ static char *displayP4(Op *pOp, char *zTemp, int nTemp){
             break;
           }
           zTemp[i++] = ',';
-          if( pKeyInfo->aSortOrder && pKeyInfo->aSortOrder[j] ){
+          if( pKeyInfo->aSortOrder[j] ){
             zTemp[i++] = '-';
           }
           memcpy(&zTemp[i], pColl->zName,n+1);
@@ -2877,6 +2877,7 @@ UnpackedRecord *sqlite3VdbeAllocUnpackedRecord(
   }
 
   p->aMem = (Mem*)&((char*)p)[ROUND8(sizeof(UnpackedRecord))];
+  assert( pKeyInfo->aSortOrder!=0 );
   p->pKeyInfo = pKeyInfo;
   p->nField = pKeyInfo->nField + 1;
   return p;
@@ -2970,6 +2971,7 @@ int sqlite3VdbeRecordCompare(
   idx1 = getVarint32(aKey1, szHdr1);
   d1 = szHdr1;
   nField = pKeyInfo->nField;
+  assert( pKeyInfo->aSortOrder!=0 );
   while( idx1<szHdr1 && i<pPKey2->nField ){
     u32 serial_type1;
 
@@ -2989,7 +2991,7 @@ int sqlite3VdbeRecordCompare(
       assert( mem1.zMalloc==0 );  /* See comment below */
 
       /* Invert the result if we are using DESC sort order. */
-      if( pKeyInfo->aSortOrder && i<nField && pKeyInfo->aSortOrder[i] ){
+      if( i<nField && pKeyInfo->aSortOrder[i] ){
         rc = -rc;
       }