Performance optimizations in the VDBE and especially to the OP_Next and

related opcodes and in the sqlite3BtreeNext() and sqlite3BtreePrevious()
routines.  This is a cherrypick of [6f99b54aedeb], [d2efea1682a7], and
[d78c5d89de4b].

FossilOrigin-Name: 7f72fc4f47445a2c01910b268335873de9f75059

manifest

@@ -1,5 +1,5 @@
-C Performance\simprovement\sin\ssqlite3BtreeNext()\sand\ssqlite3BtreePrevious()\nfor\sthe\scommon\scase\sof\sa\svalid\scursor.
+C Performance\soptimizations\sin\sthe\sVDBE\sand\sespecially\sto\sthe\sOP_Next\sand\nrelated\sopcodes\sand\sin\sthe\ssqlite3BtreeNext()\sand\ssqlite3BtreePrevious()\nroutines.\s\sThis\sis\sa\scherrypick\sof\s[6f99b54aedeb],\s[d2efea1682a7],\sand\n[d78c5d89de4b].
-D 2013-08-19T20:04:10.623
+D 2013-08-20T03:13:51.513
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in 5e41da95d92656a5004b03d3576e8b226858a28e
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -163,9 +163,9 @@ F src/auth.c 523da7fb4979469955d822ff9298352d6b31de34
 F src/backup.c 43b348822db3e4cef48b2ae5a445fbeb6c73a165
 F src/bitvec.c 19a4ba637bd85f8f63fc8c9bae5ade9fb05ec1cb
 F src/btmutex.c 976f45a12e37293e32cae0281b15a21d48a8aaa7
-F src/btree.c 78287b3012fe65fd5e38927d40c01e01a783e016
+F src/btree.c adea13e65d6c7b969bcd74cea6ae79b2d3c393fa
 F src/btree.h bfe0e8c5759b4ec77b0d18390064a6ef3cdffaaf
-F src/btreeInt.h eecc84f02375b2bb7a44abbcbbe3747dde73edb2
+F src/btreeInt.h 51cf220a9b9223354770883e93a859dc377aa27f
 F src/build.c f99a715ff9290996b579d5e1ec8e94239dc9ae5e
 F src/callback.c d7e46f40c3cf53c43550b7da7a1d0479910b62cc
 F src/complete.c dc1d136c0feee03c2f7550bafc0d29075e36deac
@@ -277,10 +277,10 @@ F src/update.c 7f3fe64d8f3b44c44a1eac293f0f85f87c355b7a
 F src/utf.c 8d819e2e5104a430fc2005f018db14347c95a38f
 F src/util.c f566b5138099a2df8533b190d0dcc74b7dfbe0c9
 F src/vacuum.c d9c5759f4c5a438bb43c2086f72c5d2edabc36c8
-F src/vdbe.c 0fbe7a904a1187dc6c8a2dbe2f594f0ce8d01401
+F src/vdbe.c 938feb53407dee2234849aad0f103ae9b941595e
 F src/vdbe.h 4f554b5627f26710c4c36d919110a3fc611ca5c4
-F src/vdbeInt.h e9b7c6b165a31a4715c5aa97223d20d265515231
+F src/vdbeInt.h cbe71b8b36d8b3bba5709cc3f436c7e3b47b7b08
-F src/vdbeapi.c 4d13580bd058b39623e8fcfc233b7df4b8191e8b
+F src/vdbeapi.c 96b24b946cf21894f63d9393e821baa2f0a80979
 F src/vdbeaux.c a6ea36a9dc714e1128a0173249a0532ddcab0489
 F src/vdbeblob.c 5dc79627775bd9a9b494dd956e26297946417d69
 F src/vdbemem.c 833005f1cbbf447289f1973dba2a0c2228c7b8ab
@@ -1105,7 +1105,10 @@ F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4
 F tool/warnings.sh fbc018d67fd7395f440c28f33ef0f94420226381
 F tool/wherecosttest.c f407dc4c79786982a475261866a161cd007947ae
 F tool/win/sqlite.vsix 97894c2790eda7b5bce3cc79cb2a8ec2fde9b3ac
-P d6c4d48a002a6d7057fccc30064ce0b049678f0c
+P dc65ad8c4c67b21e3b042b8df6580d02b634a90b
-R 5570190c517979d35e3b41a2553566a9
+Q +6f99b54aedeb91e46d52f65504d02a9cc61c0062
+Q +d2efea1682a7e708000c1f5d36370aaf1199b3be
+Q +d78c5d89de4b840351b026c9db1952fc24e689d0
+R 539c71750e964e780f11bfb1b59ee716
 U drh
-Z 8413b4240dd170b2f74e62b701d0cb1c
+Z feae42d544c0a4532e8cd3cb8461eca6

manifest.uuid

@@ -1 +1 @@
-dc65ad8c4c67b21e3b042b8df6580d02b634a90b
+7f72fc4f47445a2c01910b268335873de9f75059

src/btree.c

@@ -724,6 +724,9 @@ static int btreeRestoreCursorPosition(BtCursor *pCur){
     sqlite3_free(pCur->pKey);
     pCur->pKey = 0;
     assert( pCur->eState==CURSOR_VALID || pCur->eState==CURSOR_INVALID );
+    if( pCur->skipNext && pCur->eState==CURSOR_VALID ){
+      pCur->eState = CURSOR_SKIPNEXT;
+    }
   }
   return rc;
 }
@@ -749,7 +752,7 @@ int sqlite3BtreeCursorHasMoved(BtCursor *pCur, int *pHasMoved){
     *pHasMoved = 1;
     return rc;
   }
-  if( pCur->eState!=CURSOR_VALID || pCur->skipNext!=0 ){
+  if( pCur->eState!=CURSOR_VALID || NEVER(pCur->skipNext!=0) ){
     *pHasMoved = 1;
   }else{
     *pHasMoved = 0;
@@ -4797,23 +4800,27 @@ int sqlite3BtreeNext(BtCursor *pCur, int *pRes){
 
   assert( cursorHoldsMutex(pCur) );
   assert( pRes!=0 );
+  assert( pCur->skipNext==0 || pCur->eState!=CURSOR_VALID );
   if( pCur->eState!=CURSOR_VALID ){
     rc = restoreCursorPosition(pCur);
     if( rc!=SQLITE_OK ){
+      *pRes = 0;
       return rc;
     }
     if( CURSOR_INVALID==pCur->eState ){
       *pRes = 1;
       return SQLITE_OK;
     }
-  }
+    if( pCur->skipNext ){
-  if( pCur->skipNext ){
+      assert( pCur->eState==CURSOR_VALID || pCur->eState==CURSOR_SKIPNEXT );
-    if( pCur->skipNext>0 ){
+      pCur->eState = CURSOR_VALID;
+      if( pCur->skipNext>0 ){
+        pCur->skipNext = 0;
+        *pRes = 0;
+        return SQLITE_OK;
+      }
       pCur->skipNext = 0;
-      *pRes = 0;
-      return SQLITE_OK;
     }
-    pCur->skipNext = 0;
   }
 
   pPage = pCur->apPage[pCur->iPage];
@@ -4832,7 +4839,10 @@ int sqlite3BtreeNext(BtCursor *pCur, int *pRes){
   if( idx>=pPage->nCell ){
     if( !pPage->leaf ){
       rc = moveToChild(pCur, get4byte(&pPage->aData[pPage->hdrOffset+8]));
-      if( rc ) return rc;
+      if( rc ){
+        *pRes = 0;
+        return rc;
+      }
       rc = moveToLeftmost(pCur);
       *pRes = 0;
       return rc;
@@ -4874,24 +4884,31 @@ int sqlite3BtreePrevious(BtCursor *pCur, int *pRes){
   MemPage *pPage;
 
   assert( cursorHoldsMutex(pCur) );
+  assert( pRes!=0 );
+  assert( pCur->skipNext==0 || pCur->eState!=CURSOR_VALID );
   pCur->atLast = 0;
   if( pCur->eState!=CURSOR_VALID ){
     if( ALWAYS(pCur->eState>=CURSOR_REQUIRESEEK) ){
       rc = btreeRestoreCursorPosition(pCur);
-      if( rc!=SQLITE_OK ) return rc;
+      if( rc!=SQLITE_OK ){
+        *pRes = 0;
+        return rc;
+      }
     }
     if( CURSOR_INVALID==pCur->eState ){
       *pRes = 1;
       return SQLITE_OK;
     }
-  }
+    if( pCur->skipNext ){
-  if( pCur->skipNext ){
+      assert( pCur->eState==CURSOR_VALID || pCur->eState==CURSOR_SKIPNEXT );
-    if( pCur->skipNext<0 ){
+      pCur->eState = CURSOR_VALID;
+      if( pCur->skipNext<0 ){
+        pCur->skipNext = 0;
+        *pRes = 0;
+        return SQLITE_OK;
+      }
       pCur->skipNext = 0;
-      *pRes = 0;
-      return SQLITE_OK;
     }
-    pCur->skipNext = 0;
   }
 
   pPage = pCur->apPage[pCur->iPage];
@@ -4900,6 +4917,7 @@ int sqlite3BtreePrevious(BtCursor *pCur, int *pRes){
     int idx = pCur->aiIdx[pCur->iPage];
     rc = moveToChild(pCur, get4byte(findCell(pPage, idx)));
     if( rc ){
+      *pRes = 0;
       return rc;
     }
     rc = moveToRightmost(pCur);

src/btreeInt.h

@@ -520,14 +520,19 @@ struct BtCursor {
 /*
 ** Potential values for BtCursor.eState.
 **
-** CURSOR_VALID:
-**   Cursor points to a valid entry. getPayload() etc. may be called.
-**
 ** CURSOR_INVALID:
 **   Cursor does not point to a valid entry. This can happen (for example) 
 **   because the table is empty or because BtreeCursorFirst() has not been
 **   called.
 **
+** CURSOR_VALID:
+**   Cursor points to a valid entry. getPayload() etc. may be called.
+**
+** CURSOR_SKIPNEXT:
+**   Cursor is valid except that the Cursor.skipNext field is non-zero
+**   indicating that the next sqlite3BtreeNext() or sqlite3BtreePrevious()
+**   operation should be a no-op.
+**
 ** CURSOR_REQUIRESEEK:
 **   The table that this cursor was opened on still exists, but has been 
 **   modified since the cursor was last used. The cursor position is saved
@@ -544,8 +549,9 @@ struct BtCursor {
 */
 #define CURSOR_INVALID           0
 #define CURSOR_VALID             1
-#define CURSOR_REQUIRESEEK       2
+#define CURSOR_SKIPNEXT          2
-#define CURSOR_FAULT             3
+#define CURSOR_REQUIRESEEK       3
+#define CURSOR_FAULT             4
 
 /* 
 ** The database page the PENDING_BYTE occupies. This page is never used.

src/vdbe.c

@@ -588,7 +588,7 @@ int sqlite3VdbeExec(
 #ifndef SQLITE_OMIT_PROGRESS_CALLBACK
   if( db->xProgress ){
     assert( 0 < db->nProgressOps );
-    nProgressLimit = (unsigned)p->aCounter[SQLITE_STMTSTATUS_VM_STEP-1];
+    nProgressLimit = (unsigned)p->aCounter[SQLITE_STMTSTATUS_VM_STEP];
     if( nProgressLimit==0 ){
       nProgressLimit = db->nProgressOps;
     }else{
@@ -1449,7 +1449,7 @@ case OP_Function: {
   sqlite3VdbeMemMove(&ctx.s, pOut);
   MemSetTypeFlag(&ctx.s, MEM_Null);
 
-  ctx.isError = 0;
+  ctx.fErrorOrAux = 0;
   if( ctx.pFunc->flags & SQLITE_FUNC_NEEDCOLL ){
     assert( pOp>aOp );
     assert( pOp[-1].p4type==P4_COLLSEQ );
@@ -1460,11 +1460,6 @@ case OP_Function: {
   (*ctx.pFunc->xFunc)(&ctx, n, apVal); /* IMP: R-24505-23230 */
   lastRowid = db->lastRowid;
 
-  /* If any auxiliary data functions have been called by this user function,
-  ** immediately call the destructor for any non-static values.
-  */
-  sqlite3VdbeDeleteAuxData(p, pc, pOp->p1);
-
   if( db->mallocFailed ){
     /* Even though a malloc() has failed, the implementation of the
     ** user function may have called an sqlite3_result_XXX() function
@@ -1476,9 +1471,12 @@ case OP_Function: {
   }
 
   /* If the function returned an error, throw an exception */
-  if( ctx.isError ){
+  if( ctx.fErrorOrAux ){
-    sqlite3SetString(&p->zErrMsg, db, "%s", sqlite3_value_text(&ctx.s));
+    if( ctx.isError ){
-    rc = ctx.isError;
+      sqlite3SetString(&p->zErrMsg, db, "%s", sqlite3_value_text(&ctx.s));
+      rc = ctx.isError;
+    }
+    sqlite3VdbeDeleteAuxData(p, pc, pOp->p1);
   }
 
   /* Copy the result of the function into register P3 */
@@ -1850,12 +1848,12 @@ case OP_Ge: {             /* same as TK_GE, jump, in1, in3 */
       ** then the result is always NULL.
       ** The jump is taken if the SQLITE_JUMPIFNULL bit is set.
       */
-      if( pOp->p5 & SQLITE_STOREP2 ){
+      if( pOp->p5 & SQLITE_JUMPIFNULL ){
+        pc = pOp->p2-1;
+      }else if( pOp->p5 & SQLITE_STOREP2 ){
         pOut = &aMem[pOp->p2];
         MemSetTypeFlag(pOut, MEM_Null);
         REGISTER_TRACE(pOp->p2, pOut);
-      }else if( pOp->p5 & SQLITE_JUMPIFNULL ){
-        pc = pOp->p2-1;
       }
       break;
     }
@@ -4440,7 +4438,7 @@ case OP_Sort: {        /* jump */
   sqlite3_sort_count++;
   sqlite3_search_count--;
 #endif
-  p->aCounter[SQLITE_STMTSTATUS_SORT-1]++;
+  p->aCounter[SQLITE_STMTSTATUS_SORT]++;
   /* Fall through into OP_Rewind */
 }
 /* Opcode: Rewind P1 P2 * * *
@@ -4519,7 +4517,7 @@ case OP_Next: {        /* jump */
   int res;
 
   assert( pOp->p1>=0 && pOp->p1<p->nCursor );
-  assert( pOp->p5<=ArraySize(p->aCounter) );
+  assert( pOp->p5<ArraySize(p->aCounter) );
   pC = p->apCsr[pOp->p1];
   if( pC==0 ){
     break;  /* See ticket #2273 */
@@ -4529,7 +4527,7 @@ case OP_Next: {        /* jump */
     assert( pOp->opcode==OP_SorterNext );
     rc = sqlite3VdbeSorterNext(db, pC, &res);
   }else{
-    res = 1;
+    /* res = 1; // Always initialized by the xAdvance() call */
     assert( pC->deferredMoveto==0 );
     assert( pC->pCursor );
     assert( pOp->opcode!=OP_Next || pOp->p4.xAdvance==sqlite3BtreeNext );
@@ -4540,7 +4538,7 @@ case OP_Next: {        /* jump */
   pC->cacheStatus = CACHE_STALE;
   if( res==0 ){
     pc = pOp->p2 - 1;
-    if( pOp->p5 ) p->aCounter[pOp->p5-1]++;
+    p->aCounter[pOp->p5]++;
 #ifdef SQLITE_TEST
     sqlite3_search_count++;
 #endif
@@ -6243,7 +6241,7 @@ vdbe_error_halt:
 vdbe_return:
   db->lastRowid = lastRowid;
   testcase( nVmStep>0 );
-  p->aCounter[SQLITE_STMTSTATUS_VM_STEP-1] += (int)nVmStep;
+  p->aCounter[SQLITE_STMTSTATUS_VM_STEP] += (int)nVmStep;
   sqlite3VdbeLeave(p);
   return rc;
 

src/vdbeInt.h

@@ -266,10 +266,11 @@ struct sqlite3_context {
   Mem s;                /* The return value is stored here */
   Mem *pMem;            /* Memory cell used to store aggregate context */
   CollSeq *pColl;       /* Collating sequence */
-  int isError;          /* Error code returned by the function. */
-  int skipFlag;         /* Skip skip accumulator loading if true */
-  int iOp;              /* Instruction number of OP_Function */
   Vdbe *pVdbe;          /* The VM that owns this context */
+  int iOp;              /* Instruction number of OP_Function */
+  int isError;          /* Error code returned by the function. */
+  u8 skipFlag;          /* Skip skip accumulator loading if true */
+  u8 fErrorOrAux;       /* isError!=0 or pVdbe->pAuxData modified */
 };
 
 /*
@@ -345,7 +346,7 @@ struct Vdbe {
   yDbMask btreeMask;      /* Bitmask of db->aDb[] entries referenced */
   yDbMask lockMask;       /* Subset of btreeMask that requires a lock */
   int iStatement;         /* Statement number (or 0 if has not opened stmt) */
-  int aCounter[4];        /* Counters used by sqlite3_stmt_status() */
+  u32 aCounter[5];        /* Counters used by sqlite3_stmt_status() */
 #ifndef SQLITE_OMIT_TRACE
   i64 startTime;          /* Time when query started - used for profiling */
 #endif

src/vdbeapi.c

@@ -211,12 +211,14 @@ void sqlite3_result_double(sqlite3_context *pCtx, double rVal){
 void sqlite3_result_error(sqlite3_context *pCtx, const char *z, int n){
   assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
   pCtx->isError = SQLITE_ERROR;
+  pCtx->fErrorOrAux = 1;
   sqlite3VdbeMemSetStr(&pCtx->s, z, n, SQLITE_UTF8, SQLITE_TRANSIENT);
 }
 #ifndef SQLITE_OMIT_UTF16
 void sqlite3_result_error16(sqlite3_context *pCtx, const void *z, int n){
   assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
   pCtx->isError = SQLITE_ERROR;
+  pCtx->fErrorOrAux = 1;
   sqlite3VdbeMemSetStr(&pCtx->s, z, n, SQLITE_UTF16NATIVE, SQLITE_TRANSIENT);
 }
 #endif
@@ -280,6 +282,7 @@ void sqlite3_result_zeroblob(sqlite3_context *pCtx, int n){
 }
 void sqlite3_result_error_code(sqlite3_context *pCtx, int errCode){
   pCtx->isError = errCode;
+  pCtx->fErrorOrAux = 1;
   if( pCtx->s.flags & MEM_Null ){
     sqlite3VdbeMemSetStr(&pCtx->s, sqlite3ErrStr(errCode), -1, 
                          SQLITE_UTF8, SQLITE_STATIC);
@@ -290,6 +293,7 @@ void sqlite3_result_error_code(sqlite3_context *pCtx, int errCode){
 void sqlite3_result_error_toobig(sqlite3_context *pCtx){
   assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
   pCtx->isError = SQLITE_TOOBIG;
+  pCtx->fErrorOrAux = 1;
   sqlite3VdbeMemSetStr(&pCtx->s, "string or blob too big", -1, 
                        SQLITE_UTF8, SQLITE_STATIC);
 }
@@ -299,6 +303,7 @@ void sqlite3_result_error_nomem(sqlite3_context *pCtx){
   assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
   sqlite3VdbeMemSetNull(&pCtx->s);
   pCtx->isError = SQLITE_NOMEM;
+  pCtx->fErrorOrAux = 1;
   pCtx->s.db->mallocFailed = 1;
 }
 
@@ -621,6 +626,10 @@ void sqlite3_set_auxdata(
     pAuxData->iArg = iArg;
     pAuxData->pNext = pVdbe->pAuxData;
     pVdbe->pAuxData = pAuxData;
+    if( pCtx->fErrorOrAux==0 ){
+      pCtx->isError = 0;
+      pCtx->fErrorOrAux = 1;
+    }
   }else if( pAuxData->xDelete ){
     pAuxData->xDelete(pAuxData->pAux);
   }
@@ -1289,7 +1298,7 @@ sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt){
 */
 int sqlite3_stmt_status(sqlite3_stmt *pStmt, int op, int resetFlag){
   Vdbe *pVdbe = (Vdbe*)pStmt;
-  int v = pVdbe->aCounter[op-1];
+  u32 v = pVdbe->aCounter[op];
-  if( resetFlag ) pVdbe->aCounter[op-1] = 0;
+  if( resetFlag ) pVdbe->aCounter[op] = 0;
-  return v;
+  return (int)v;
 }