Make the VdbeCursor object even smaller. But the resulting library is bigger

and slower than trunk.  This branch is a failed experiment.

FossilOrigin-Name: 896a06cc182491d87950c287df45c0656e284d35

manifest

@@ -1,5 +1,5 @@
-C Fix\sthe\sspellfix1_scriptcode()\sfunction\sto\signore\swhitespace\sand\spunctuation,\nand\sto\srecognize\shebrew\sand\sarabic\sscripts.
-D 2015-12-17T14:18:21.904
+C Make\sthe\sVdbeCursor\sobject\seven\ssmaller.\s\sBut\sthe\sresulting\slibrary\sis\sbigger\nand\sslower\sthan\strunk.\s\sThis\sbranch\sis\sa\sfailed\sexperiment.
+D 2015-12-17T19:17:43.940
 F Makefile.in 28bcd6149e050dff35d4dcfd97e890cd387a499d
 F Makefile.linux-gcc 7bc79876b875010e8c8f9502eb935ca92aa3c434
 F Makefile.msc 5fff077fcc46de7714ed6eebb6159a4c00eab751
@@ -276,8 +276,8 @@ F src/auth.c b56c78ebe40a2110fd361379f7e8162d23f92240
 F src/backup.c 2869a76c03eb393ee795416e2387005553df72bc
 F src/bitvec.c 1a78d450a17c5016710eec900bedfc5729bf9bdf
 F src/btmutex.c 45a968cc85afed9b5e6cf55bf1f42f8d18107f79
-F src/btree.c 84ede51e371a11c3dbb3e24ccc5e3e99594a6c00
-F src/btree.h 2d76dee44704c47eed323356a758662724b674a0
+F src/btree.c cb0ed74a8212a7b31fb967a162658f490a302a18
+F src/btree.h 778f36cd143dae941e8b8d0cbc7b0f43ba35dfef
 F src/btreeInt.h 3ab435ed27adea54d040584b0bcc488ee7db1e38
 F src/build.c e83da4d004a4e050c01acbb821ff7a7b1019c29b
 F src/callback.c 7b44ce59674338ad48b0e84e7b72f935ea4f68b0
@@ -398,14 +398,14 @@ F src/update.c 17332f9fe818cbc0444c36a811800af8498af4c3
 F src/utf.c fc6b889ba0779b7722634cdeaa25f1930d93820c
 F src/util.c e802e8e311a0d6c48cd1b3e89db164f6f0248d70
 F src/vacuum.c 2ddd5cad2a7b9cef7f9e431b8c7771634c6b1701
-F src/vdbe.c 984c2be6691d3f67deb2e6747c2132150d776f32
+F src/vdbe.c 3bedca4adcf7dc42224a20049883c89819c459b0
 F src/vdbe.h efb7a8c1459e31f3ea4377824c6a7e4cb5068637
-F src/vdbeInt.h 75c2e82ee3357e9210c06474f8d9bdf12c81105d
+F src/vdbeInt.h 06caadd917765d7b981686b1dd33845023ccfbdc
 F src/vdbeapi.c 020681b943e77766b32ae1cddf86d7831b7374ca
-F src/vdbeaux.c 68082d9991fc1b8625d34c8b5db1775c9dee426e
+F src/vdbeaux.c b0d427a5070bae99f137368356674457d018c168
 F src/vdbeblob.c fdc4a81605ae7a35ae94a55bd768b66d6be16f15
 F src/vdbemem.c fdd1578e47bea61390d472de53c565781d81e045
-F src/vdbesort.c a7ec02da4494c59dfd071126dd3726be5a11459d
+F src/vdbesort.c 90a3545ed856e1007c77ca3ac4f9c1975a64ed23
 F src/vdbetrace.c 8befe829faff6d9e6f6e4dee5a7d3f85cc85f1a0
 F src/vtab.c 2a8b44aa372c33f6154208e7a7f6c44254549806
 F src/vxworks.h c18586c8edc1bddbc15c004fa16aeb1e1342b4fb
@@ -1405,7 +1405,7 @@ F tool/vdbe_profile.tcl 246d0da094856d72d2c12efec03250d71639d19f
 F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4
 F tool/warnings.sh 48bd54594752d5be3337f12c72f28d2080cb630b
 F tool/win/sqlite.vsix deb315d026cc8400325c5863eef847784a219a2f
-P 85ebd46c701e0a094a4690cd8f1d0cbae9aa257c
-R 70cdc580d7d9b92b032d33f5e0d50f2e
+P 98b710c36343fc213c8223f353907934be60b60d
+R 10fdd2deb8319d6498b358eb4665321f
 U drh
-Z 6d4b5ed9cd1870281d7d851922f323d8
+Z dceb428fbc78dc00f293c1c742052765

manifest.uuid

@@ -1 +1 @@
-7adfa4a5794e47f97491c08abeaaac90e826b331
+896a06cc182491d87950c287df45c0656e284d35

src/btree.c

@@ -4182,6 +4182,14 @@ void sqlite3BtreeCursorZero(BtCursor *p){
   memset(p, 0, offsetof(BtCursor, iPage));
 }
 
+/*
+** Return the Btree object associated with a BtCursor.
+*/
+Btree *sqlite3BtreeOfCursor(BtCursor *p){
+  assert( p!=0 );
+  return p->pBtree;
+}
+
 /*
 ** Close a cursor.  The read lock on the database file is released
 ** when the last cursor is closed.

src/btree.h

@@ -221,6 +221,7 @@ int sqlite3BtreeCursor(
 int sqlite3BtreeCursorSize(void);
 void sqlite3BtreeCursorZero(BtCursor*);
 void sqlite3BtreeCursorHintFlags(BtCursor*, unsigned);
+Btree *sqlite3BtreeOfCursor(BtCursor*);
 #ifdef SQLITE_ENABLE_CURSOR_HINTS
 void sqlite3BtreeCursorHint(BtCursor*, int, ...);
 #endif

src/vdbe.c

@@ -3441,6 +3441,7 @@ case OP_OpenAutoindex:
 case OP_OpenEphemeral: {
   VdbeCursor *pCx;
   KeyInfo *pKeyInfo;
+  Btree *pBt;
 
   static const int vfsFlags = 
       SQLITE_OPEN_READWRITE |
@@ -3453,35 +3454,39 @@ case OP_OpenEphemeral: {
   pCx = allocateCursor(p, pOp->p1, pOp->p2, -1, CURTYPE_BTREE);
   if( pCx==0 ) goto no_mem;
   pCx->nullRow = 1;
-  pCx->isEphemeral = 1;
-  rc = sqlite3BtreeOpen(db->pVfs, 0, db, &pCx->pBt, 
+  rc = sqlite3BtreeOpen(db->pVfs, 0, db, &pBt, 
                         BTREE_OMIT_JOURNAL | BTREE_SINGLE | pOp->p5, vfsFlags);
   if( rc==SQLITE_OK ){
-    rc = sqlite3BtreeBeginTrans(pCx->pBt, 1);
-  }
-  if( rc==SQLITE_OK ){
-    /* If a transient index is required, create it by calling
-    ** sqlite3BtreeCreateTable() with the BTREE_BLOBKEY flag before
-    ** opening it. If a transient table is required, just use the
-    ** automatically created table with root-page 1 (an BLOB_INTKEY table).
-    */
-    if( (pKeyInfo = pOp->p4.pKeyInfo)!=0 ){
-      int pgno;
-      assert( pOp->p4type==P4_KEYINFO );
-      rc = sqlite3BtreeCreateTable(pCx->pBt, &pgno, BTREE_BLOBKEY | pOp->p5); 
-      if( rc==SQLITE_OK ){
-        assert( pgno==MASTER_ROOT+1 );
-        assert( pKeyInfo->db==db );
-        assert( pKeyInfo->enc==ENC(db) );
-        pCx->pKeyInfo = pKeyInfo;
-        rc = sqlite3BtreeCursor(pCx->pBt, pgno, BTREE_WRCSR,
-                                pKeyInfo, pCx->uc.pCursor);
+    rc = sqlite3BtreeBeginTrans(pBt, 1);
+    if( rc==SQLITE_OK ){
+      /* If a transient index is required, create it by calling
+      ** sqlite3BtreeCreateTable() with the BTREE_BLOBKEY flag before
+      ** opening it. If a transient table is required, just use the
+      ** automatically created table with root-page 1 (an BLOB_INTKEY table).
+      */
+      if( (pKeyInfo = pOp->p4.pKeyInfo)!=0 ){
+        int pgno;
+        assert( pOp->p4type==P4_KEYINFO );
+        rc = sqlite3BtreeCreateTable(pBt, &pgno, BTREE_BLOBKEY | pOp->p5); 
+        if( rc==SQLITE_OK ){
+          assert( pgno==MASTER_ROOT+1 );
+          assert( pKeyInfo->db==db );
+          assert( pKeyInfo->enc==ENC(db) );
+          pCx->pKeyInfo = pKeyInfo;
+          rc = sqlite3BtreeCursor(pBt, pgno, BTREE_WRCSR,
+                                  pKeyInfo, pCx->uc.pCursor);
+        }
+        pCx->isTable = 0;
+      }else{
+        rc = sqlite3BtreeCursor(pBt, MASTER_ROOT, BTREE_WRCSR,
+                                0, pCx->uc.pCursor);
+        pCx->isTable = 1;
       }
-      pCx->isTable = 0;
+    }
+    if( rc==SQLITE_OK ){
+      pCx->isEphemeral = 1;
     }else{
-      rc = sqlite3BtreeCursor(pCx->pBt, MASTER_ROOT, BTREE_WRCSR,
-                              0, pCx->uc.pCursor);
-      pCx->isTable = 1;
+      sqlite3BtreeClose(pBt);
     }
   }
   pCx->isOrdered = (pOp->p5!=BTREE_UNORDERED);
@@ -3524,7 +3529,8 @@ case OP_SequenceTest: {
   assert( pOp->p1>=0 && pOp->p1<p->nCursor );
   pC = p->apCsr[pOp->p1];
   assert( isSorter(pC) );
-  if( (pC->seqCount++)==0 ){
+  assert( !pC->movetoUsed );
+  if( (pC->ux.seqCount++)==0 ){
     goto jump_to_p2;
   }
   break;
@@ -3754,7 +3760,8 @@ case OP_SeekGT: {       /* jump, in3 */
       }
     } 
     rc = sqlite3BtreeMovetoUnpacked(pC->uc.pCursor, 0, (u64)iKey, 0, &res);
-    pC->movetoTarget = iKey;  /* Used by OP_Delete */
+    VVA_ONLY( pC->movetoUsed = 1; )
+    pC->ux.movetoTarget = iKey;  /* Used by OP_Delete */
     if( rc!=SQLITE_OK ){
       goto abort_due_to_error;
     }
@@ -3862,11 +3869,13 @@ case OP_Seek: {    /* in2 */
   pC = p->apCsr[pOp->p1];
   assert( pC!=0 );
   assert( pC->eCurType==CURTYPE_BTREE );
+  assert( !pC->isEphemeral );
   assert( pC->uc.pCursor!=0 );
   assert( pC->isTable );
   pC->nullRow = 0;
   pIn2 = &aMem[pOp->p2];
-  pC->movetoTarget = sqlite3VdbeIntValue(pIn2);
+  VVA_ONLY( pC->movetoUsed = 1; )
+  pC->ux.movetoTarget = sqlite3VdbeIntValue(pIn2);
   pC->deferredMoveto = 1;
   break;
 }
@@ -4055,7 +4064,8 @@ case OP_NotExists: {        /* jump, in3 */
   iKey = pIn3->u.i;
   rc = sqlite3BtreeMovetoUnpacked(pCrsr, 0, iKey, 0, &res);
   assert( rc==SQLITE_OK || res==0 );
-  pC->movetoTarget = iKey;  /* Used by OP_Delete */
+  VVA_ONLY( pC->movetoUsed = 1; )
+  pC->ux.movetoTarget = iKey;  /* Used by OP_Delete */
   pC->nullRow = 0;
   pC->cacheStatus = CACHE_STALE;
   pC->deferredMoveto = 0;
@@ -4083,9 +4093,11 @@ case OP_NotExists: {        /* jump, in3 */
 case OP_Sequence: {           /* out2 */
   assert( pOp->p1>=0 && pOp->p1<p->nCursor );
   assert( p->apCsr[pOp->p1]!=0 );
-  assert( p->apCsr[pOp->p1]->eCurType!=CURTYPE_VTAB );
+  assert( p->apCsr[pOp->p1]->eCurType==CURTYPE_BTREE );
+  assert( p->apCsr[pOp->p1]->isEphemeral );
+  assert( !p->apCsr[pOp->p1]->movetoUsed );
   pOut = out2Prerelease(p, pOp);
-  pOut->u.i = p->apCsr[pOp->p1]->seqCount++;
+  pOut->u.i = p->apCsr[pOp->p1]->ux.seqCount++;
   break;
 }
 
@@ -4370,17 +4382,17 @@ case OP_Delete: {
 
   hasUpdateCallback = db->xUpdateCallback && pOp->p4.z && pC->isTable;
   if( pOp->p5 && hasUpdateCallback ){
-    sqlite3BtreeKeySize(pC->uc.pCursor, &pC->movetoTarget);
+    sqlite3BtreeKeySize(pC->uc.pCursor, &pC->ux.movetoTarget);
   }
 
 #ifdef SQLITE_DEBUG
   /* The seek operation that positioned the cursor prior to OP_Delete will
-  ** have also set the pC->movetoTarget field to the rowid of the row that
+  ** have also set the pC->ux.movetoTarget field to the rowid of the row that
   ** is being deleted */
   if( pOp->p4.z && pC->isTable && pOp->p5==0 ){
     i64 iKey = 0;
     sqlite3BtreeKeySize(pC->uc.pCursor, &iKey);
-    assert( pC->movetoTarget==iKey ); 
+    assert( pC->ux.movetoTarget==iKey ); 
   }
 #endif
  
@@ -4390,7 +4402,7 @@ case OP_Delete: {
   /* Invoke the update-hook if required. */
   if( rc==SQLITE_OK && hasUpdateCallback ){
     db->xUpdateCallback(db->pUpdateArg, SQLITE_DELETE,
-                        db->aDb[pC->iDb].zName, pOp->p4.z, pC->movetoTarget);
+                        db->aDb[pC->iDb].zName, pOp->p4.z, pC->ux.movetoTarget);
     assert( pC->iDb>=0 );
   }
   if( pOp->p2 & OPFLAG_NCHANGE ) p->nChange++;
@@ -4581,7 +4593,7 @@ case OP_Rowid: {                 /* out2 */
     pOut->flags = MEM_Null;
     break;
   }else if( pC->deferredMoveto ){
-    v = pC->movetoTarget;
+    v = pC->ux.movetoTarget;
 #ifndef SQLITE_OMIT_VIRTUALTABLE
   }else if( pC->eCurType==CURTYPE_VTAB ){
     assert( pC->uc.pVCur!=0 );

src/vdbeInt.h

@@ -77,16 +77,18 @@ typedef struct AuxData AuxData;
 struct VdbeCursor {
   u8 eCurType;          /* One of the CURTYPE_* values above */
   i8 iDb;               /* Index of cursor database in db->aDb[] (or -1) */
-  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 */
 #ifdef SQLITE_DEBUG
   u8 seekOp;            /* Most recent seek operation on this cursor */
+  Bool movetoUsed:1;    /* True if ux.movetoTarget has been used */
 #endif
+  Bool nullRow:1;        /* True if pointing to a row with no data */
+  Bool deferredMoveto:1; /* A call to sqlite3BtreeMoveto() is needed */
+  Bool isTable:1;        /* True for rowid tables.  False for indexes */
   Bool isEphemeral:1;   /* True for an ephemeral table */
   Bool useRandomRowid:1;/* Generate new record numbers semi-randomly */
   Bool isOrdered:1;     /* True if the underlying table is BTREE_UNORDERED */
   Pgno pgnoRoot;        /* Root page of the open btree cursor */
+  int seekResult;       /* Result of previous sqlite3BtreeMoveto() */
   i16 nField;           /* Number of fields in the header */
   u16 nHdrParsed;       /* Number of header fields parsed so far */
   union {
@@ -95,11 +97,11 @@ struct VdbeCursor {
     int pseudoTableReg;         /* CURTYPE_PSEUDO. Reg holding content. */
     VdbeSorter *pSorter;        /* CURTYPE_SORTER. Sorter object */
   } uc;
-  Btree *pBt;           /* Separate file holding temporary table */
   KeyInfo *pKeyInfo;    /* Info about index keys needed by index cursors */
-  int seekResult;       /* Result of previous sqlite3BtreeMoveto() */
-  i64 seqCount;         /* Sequence counter */
-  i64 movetoTarget;     /* Argument to the deferred sqlite3BtreeMoveto() */
+  union {
+    i64 seqCount;         /* Sequence counter.  Only valid if movetoUsed==0 */
+    i64 movetoTarget;     /* Rowid moved to. */
+  } ux;
 #ifdef SQLITE_ENABLE_COLUMN_USED_MASK
   u64 maskUsed;         /* Mask of columns used by this cursor */
 #endif

src/vdbeaux.c

@@ -1925,19 +1925,19 @@ void sqlite3VdbeFreeCursor(Vdbe *p, VdbeCursor *pCx){
   if( pCx==0 ){
     return;
   }
-  assert( pCx->pBt==0 || pCx->eCurType==CURTYPE_BTREE );
+  assert( pCx->isEphemeral==0 || pCx->eCurType==CURTYPE_BTREE );
   switch( pCx->eCurType ){
     case CURTYPE_SORTER: {
       sqlite3VdbeSorterClose(p->db, pCx);
       break;
     }
     case CURTYPE_BTREE: {
-      if( pCx->pBt ){
-        sqlite3BtreeClose(pCx->pBt);
+      assert( pCx->uc.pCursor!=0 );
+      if( pCx->isEphemeral ){
+        sqlite3BtreeClose(sqlite3BtreeOfCursor(pCx->uc.pCursor));
         /* The pCx->pCursor will be close automatically, if it exists, by
         ** the call above. */
       }else{
-        assert( pCx->uc.pCursor!=0 );
         sqlite3BtreeCloseCursor(pCx->uc.pCursor);
       }
       break;
@@ -2940,7 +2940,9 @@ static int SQLITE_NOINLINE handleDeferredMoveto(VdbeCursor *p){
   assert( p->deferredMoveto );
   assert( p->isTable );
   assert( p->eCurType==CURTYPE_BTREE );
-  rc = sqlite3BtreeMovetoUnpacked(p->uc.pCursor, 0, p->movetoTarget, 0, &res);
+  assert( !p->isEphemeral );
+  assert( p->movetoUsed );
+  rc = sqlite3BtreeMovetoUnpacked(p->uc.pCursor, 0, p->ux.movetoTarget, 0,&res);
   if( rc ) return rc;
   if( res!=0 ) return SQLITE_CORRUPT_BKPT;
 #ifdef SQLITE_TEST

src/vdbesort.c

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