Small performance and size optimization to allocateCursor().

FossilOrigin-Name: 23f042669aff535afa6ee9de367656848d01e90a1c9dab9359fa938a615b4195

manifest

@@ -1,5 +1,5 @@
-C Remove\sunnecessary\sassignment\soperations\sin\sthe\sbtree\ssearch\salgorithm,\nfor\sa\ssmall\ssize\sreduction\sand\sperformance\sincrease.
-D 2022-01-02T21:53:54.680
+C Small\sperformance\sand\ssize\soptimization\sto\sallocateCursor().
+D 2022-01-03T01:43:28.096
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@@ -622,14 +622,14 @@ F src/upsert.c 8789047a8f0a601ea42fa0256d1ba3190c13746b6ba940fe2d25643a7e991937
 F src/utf.c ee39565f0843775cc2c81135751ddd93eceb91a673ea2c57f61c76f288b041a0
 F src/util.c 89e51820bcb468ff3877a8d942f5cc807208087f021227e0927693e928a195bc
 F src/vacuum.c 6c38ddc52f0619865c91dae9c441d4d48bf3040d7dc1bc5b22da1e45547ed0b3
-F src/vdbe.c 05c8fd957820626aae224656b3db272fb4e69bf000e7bcdf62d00307cc9be873
+F src/vdbe.c 23116cc5d99ada73e8e11addabc380c27758688a16d84d0efa6dbe94c1293a4f
 F src/vdbe.h 25dabb25c7e157b84e59260cfb5b466c3ac103ede9f36f4db371332c47601abe
-F src/vdbeInt.h a7f01b0cd0dcb496343eacd37b0839250f9a718199ab6096e3995db42dec3ec8
+F src/vdbeInt.h d89d5d2150500cfb08615329fd20aea9d746bba5f2c3ecb8a17e2d2d9be029e5
 F src/vdbeapi.c 22c79072ae7d8a01e9bcae8ba16e918d60d202eaa9553b5fda38f99f7464d99a
-F src/vdbeaux.c 44b4c238425726a7e790ce54dc4aef3be3fb7ef46a70f09adb5e84c0361824ec
+F src/vdbeaux.c c1b452cc17f5887b3d36bc277a2181914d6bed508ea45827b5f348160491e6a6
 F src/vdbeblob.c 29c4118f7ee615cdee829e8401f6ead1b96b95d545b4de0042f6de39c962c652
 F src/vdbemem.c da4d594084d581be6436582bb44bb128feeb138a3e6c313eda6749ebdc3a65ec
-F src/vdbesort.c 513b481c8bab4a6578c92194a60cf3bc3b48736e4a53f8d2d7918121c5b594e7
+F src/vdbesort.c 43756031ca7430f7aec3ef904824a7883c4ede783e51f280d99b9b65c0796e35
 F src/vdbetrace.c fe0bc29ebd4e02c8bc5c1945f1d2e6be5927ec12c06d89b03ef2a4def34bf823
 F src/vdbevtab.c f99b275366c5fc5e2d99f734729880994ab9500bdafde7fae3b02d562b9d323c
 F src/vtab.c a47cc12ebaa350800c0c87b6b0095debbb5a6ed32727bcab9d82ad070a81b738
@@ -1936,8 +1936,8 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P 728e9dcc6d211acd787837c41cb62275284b5e02f55bd28bf5a44e233bcb057a
-R 8e972dcab3c6d036a102fca8bdbc15cf
+P 01bd266eb682feed901a0995c2232b62d8444d19dbb227095dfbfe8edeaa5d88
+R 8bbbbc86742a232c4562b5ad64d27946
 U drh
-Z 70eaf19d957dcced1788f060f027844f
+Z 57988afa28021d7cb9d1163c06091947
 # Remove this line to create a well-formed Fossil manifest.

manifest.uuid

@@ -1 +1 @@
-01bd266eb682feed901a0995c2232b62d8444d19dbb227095dfbfe8edeaa5d88
+23f042669aff535afa6ee9de367656848d01e90a1c9dab9359fa938a615b4195

src/vdbe.c

@@ -241,7 +241,6 @@ static VdbeCursor *allocateCursor(
   Vdbe *p,              /* The virtual machine */
   int iCur,             /* Index of the new VdbeCursor */
   int nField,           /* Number of fields in the table or index */
-  int iDb,              /* Database the cursor belongs to, or -1 */
   u8 eCurType           /* Type of the new cursor */
 ){
   /* Find the memory cell that will be used to store the blob of memory
@@ -298,7 +297,6 @@ static VdbeCursor *allocateCursor(
   p->apCsr[iCur] = pCx = (VdbeCursor*)pMem->zMalloc;
   memset(pCx, 0, offsetof(VdbeCursor,pAltCursor));
   pCx->eCurType = eCurType;
-  pCx->iDb = iDb;
   pCx->nField = nField;
   pCx->aOffset = &pCx->aType[nField];
   if( eCurType==CURTYPE_BTREE ){
@@ -2692,6 +2690,7 @@ case OP_Column: {
   assert( pC!=0 );
   assert( p2<(u32)pC->nField );
   aOffset = pC->aOffset;
+  assert( aOffset==pC->aType+pC->nField );
   assert( pC->eCurType!=CURTYPE_VTAB );
   assert( pC->eCurType!=CURTYPE_PSEUDO || pC->nullRow );
   assert( pC->eCurType!=CURTYPE_SORTER );
@@ -4019,8 +4018,9 @@ case OP_OpenWrite:
   assert( pOp->p1>=0 );
   assert( nField>=0 );
   testcase( nField==0 );  /* Table with INTEGER PRIMARY KEY and nothing else */
-  pCur = allocateCursor(p, pOp->p1, nField, iDb, CURTYPE_BTREE);
+  pCur = allocateCursor(p, pOp->p1, nField, CURTYPE_BTREE);
   if( pCur==0 ) goto no_mem;
+  pCur->iDb = iDb;
   pCur->nullRow = 1;
   pCur->isOrdered = 1;
   pCur->pgnoRoot = p2;
@@ -4062,7 +4062,7 @@ case OP_OpenDup: {
   assert( pOrig );
   assert( pOrig->isEphemeral );  /* Only ephemeral cursors can be duplicated */
 
-  pCx = allocateCursor(p, pOp->p1, pOrig->nField, -1, CURTYPE_BTREE);
+  pCx = allocateCursor(p, pOp->p1, pOrig->nField, CURTYPE_BTREE);
   if( pCx==0 ) goto no_mem;
   pCx->nullRow = 1;
   pCx->isEphemeral = 1;
@@ -4070,10 +4070,10 @@ case OP_OpenDup: {
   pCx->isTable = pOrig->isTable;
   pCx->pgnoRoot = pOrig->pgnoRoot;
   pCx->isOrdered = pOrig->isOrdered;
-  pCx->pBtx = pOrig->pBtx;
+  pCx->ub.pBtx = pOrig->ub.pBtx;
   pCx->hasBeenDuped = 1;
   pOrig->hasBeenDuped = 1;
-  rc = sqlite3BtreeCursor(pCx->pBtx, pCx->pgnoRoot, BTREE_WRCSR, 
+  rc = sqlite3BtreeCursor(pCx->ub.pBtx, pCx->pgnoRoot, BTREE_WRCSR, 
                           pCx->pKeyInfo, pCx->uc.pCursor);
   /* The sqlite3BtreeCursor() routine can only fail for the first cursor
   ** opened for a database.  Since there is already an open cursor when this
@@ -4146,16 +4146,16 @@ case OP_OpenEphemeral: {
     assert( pCx->isEphemeral );
     pCx->seqCount = 0;
     pCx->cacheStatus = CACHE_STALE;
-    rc = sqlite3BtreeClearTable(pCx->pBtx, pCx->pgnoRoot, 0);
+    rc = sqlite3BtreeClearTable(pCx->ub.pBtx, pCx->pgnoRoot, 0);
   }else{
-    pCx = allocateCursor(p, pOp->p1, pOp->p2, -1, CURTYPE_BTREE);
+    pCx = allocateCursor(p, pOp->p1, pOp->p2, CURTYPE_BTREE);
     if( pCx==0 ) goto no_mem;
     pCx->isEphemeral = 1;
-    rc = sqlite3BtreeOpen(db->pVfs, 0, db, &pCx->pBtx, 
+    rc = sqlite3BtreeOpen(db->pVfs, 0, db, &pCx->ub.pBtx, 
                           BTREE_OMIT_JOURNAL | BTREE_SINGLE | pOp->p5,
                           vfsFlags);
     if( rc==SQLITE_OK ){
-      rc = sqlite3BtreeBeginTrans(pCx->pBtx, 1, 0);
+      rc = sqlite3BtreeBeginTrans(pCx->ub.pBtx, 1, 0);
       if( rc==SQLITE_OK ){
         /* If a transient index is required, create it by calling
         ** sqlite3BtreeCreateTable() with the BTREE_BLOBKEY flag before
@@ -4164,26 +4164,26 @@ case OP_OpenEphemeral: {
         */
         if( (pCx->pKeyInfo = pKeyInfo = pOp->p4.pKeyInfo)!=0 ){
           assert( pOp->p4type==P4_KEYINFO );
-          rc = sqlite3BtreeCreateTable(pCx->pBtx, &pCx->pgnoRoot,
+          rc = sqlite3BtreeCreateTable(pCx->ub.pBtx, &pCx->pgnoRoot,
               BTREE_BLOBKEY | pOp->p5); 
           if( rc==SQLITE_OK ){
             assert( pCx->pgnoRoot==SCHEMA_ROOT+1 );
             assert( pKeyInfo->db==db );
             assert( pKeyInfo->enc==ENC(db) );
-            rc = sqlite3BtreeCursor(pCx->pBtx, pCx->pgnoRoot, BTREE_WRCSR,
+            rc = sqlite3BtreeCursor(pCx->ub.pBtx, pCx->pgnoRoot, BTREE_WRCSR,
                 pKeyInfo, pCx->uc.pCursor);
           }
           pCx->isTable = 0;
         }else{
           pCx->pgnoRoot = SCHEMA_ROOT;
-          rc = sqlite3BtreeCursor(pCx->pBtx, SCHEMA_ROOT, BTREE_WRCSR,
+          rc = sqlite3BtreeCursor(pCx->ub.pBtx, SCHEMA_ROOT, BTREE_WRCSR,
               0, pCx->uc.pCursor);
           pCx->isTable = 1;
         }
       }
       pCx->isOrdered = (pOp->p5!=BTREE_UNORDERED);
       if( rc ){
-        sqlite3BtreeClose(pCx->pBtx);
+        sqlite3BtreeClose(pCx->ub.pBtx);
       }
     }
   }
@@ -4207,7 +4207,7 @@ case OP_SorterOpen: {
 
   assert( pOp->p1>=0 );
   assert( pOp->p2>=0 );
-  pCx = allocateCursor(p, pOp->p1, pOp->p2, -1, CURTYPE_SORTER);
+  pCx = allocateCursor(p, pOp->p1, pOp->p2, CURTYPE_SORTER);
   if( pCx==0 ) goto no_mem;
   pCx->pKeyInfo = pOp->p4.pKeyInfo;
   assert( pCx->pKeyInfo->db==db );
@@ -4256,7 +4256,7 @@ case OP_OpenPseudo: {
 
   assert( pOp->p1>=0 );
   assert( pOp->p3>=0 );
-  pCx = allocateCursor(p, pOp->p1, pOp->p3, -1, CURTYPE_PSEUDO);
+  pCx = allocateCursor(p, pOp->p1, pOp->p3, CURTYPE_PSEUDO);
   if( pCx==0 ) goto no_mem;
   pCx->nullRow = 1;
   pCx->seekResult = pOp->p2;
@@ -6196,9 +6196,9 @@ case OP_IdxRowid: {           /* out2 */
       pTabCur->movetoTarget = rowid;
       pTabCur->deferredMoveto = 1;
       assert( pOp->p4type==P4_INTARRAY || pOp->p4.ai==0 );
-      pTabCur->aAltMap = pOp->p4.ai;
-      assert( !pC->isEphemeral );
       assert( !pTabCur->isEphemeral );
+      pTabCur->ub.aAltMap = pOp->p4.ai;
+      assert( !pC->isEphemeral );
       pTabCur->pAltCursor = pC;
     }else{
       pOut = out2Prerelease(p, pOp);
@@ -7720,7 +7720,7 @@ case OP_VOpen: {
   pVCur->pVtab = pVtab;
 
   /* Initialize vdbe cursor object */
-  pCur = allocateCursor(p, pOp->p1, 0, -1, CURTYPE_VTAB);
+  pCur = allocateCursor(p, pOp->p1, 0, CURTYPE_VTAB);
   if( pCur ){
     pCur->uc.pVCur = pVCur;
     pVtab->nRef++;

src/vdbeInt.h

@@ -75,7 +75,7 @@ typedef struct AuxData AuxData;
 typedef struct VdbeCursor VdbeCursor;
 struct VdbeCursor {
   u8 eCurType;            /* One of the CURTYPE_* values above */
-  i8 iDb;                 /* Index of cursor database in db->aDb[] (or -1) */
+  i8 iDb;                 /* Index of cursor database in db->aDb[] */
   u8 nullRow;             /* True if pointing to a row with no data */
   u8 deferredMoveto;      /* A call to sqlite3BtreeMoveto() is needed */
   u8 isTable;             /* True for rowid tables.  False for indexes */
@@ -88,9 +88,11 @@ struct VdbeCursor {
   Bool isOrdered:1;       /* True if the table is not BTREE_UNORDERED */
   Bool hasBeenDuped:1;    /* This cursor was source or target of OP_OpenDup */
   u16 seekHit;            /* See the OP_SeekHit and OP_IfNoHope opcodes */
-  Btree *pBtx;            /* Separate file holding temporary table */
+  union {                 /* pBtx for isEphermeral.  pAltMap otherwise */
+    Btree *pBtx;            /* Separate file holding temporary table */
+    u32 *aAltMap;           /* Mapping from table to index column numbers */
+  } ub;
   i64 seqCount;           /* Sequence counter */
-  u32 *aAltMap;           /* Mapping from table to index column numbers */
 
   /* Cached OP_Column parse information is only valid if cacheStatus matches
   ** Vdbe.cacheCtr.  Vdbe.cacheCtr will never take on the value of

src/vdbeaux.c

@@ -2470,8 +2470,6 @@ void sqlite3VdbeFreeCursor(Vdbe *p, VdbeCursor *pCx){
   if( pCx==0 ){
     return;
   }
-  assert( pCx->pBtx==0 || pCx->eCurType==CURTYPE_BTREE );
-  assert( pCx->pBtx==0 || pCx->isEphemeral );
   switch( pCx->eCurType ){
     case CURTYPE_SORTER: {
       sqlite3VdbeSorterClose(p->db, pCx);
@@ -3573,7 +3571,7 @@ int sqlite3VdbeCursorMoveto(VdbeCursor **pp, u32 *piCol){
   if( p->deferredMoveto ){
     u32 iMap;
     assert( !p->isEphemeral );
-    if( p->aAltMap && (iMap = p->aAltMap[1+*piCol])>0 && !p->nullRow ){
+    if( p->ub.aAltMap && (iMap = p->ub.aAltMap[1+*piCol])>0 && !p->nullRow ){
       *pp = p->pAltCursor;
       *piCol = iMap - 1;
       return SQLITE_OK;

src/vdbesort.c

@@ -960,7 +960,8 @@ int sqlite3VdbeSorterInit(
   }
 #endif
 
-  assert( pCsr->pKeyInfo && pCsr->pBtx==0 );
+  assert( pCsr->pKeyInfo );
+  assert( !pCsr->isEphemeral );
   assert( pCsr->eCurType==CURTYPE_SORTER );
   szKeyInfo = sizeof(KeyInfo) + (pCsr->pKeyInfo->nKeyField-1)*sizeof(CollSeq*);
   sz = sizeof(VdbeSorter) + nWorker * sizeof(SortSubtask);