Split out all four cases of cellSizePtr() into different methods, each optimized

for the specific page type.  This gives a 0.36% performance increase at a cost
of about 300 bytes of code.

FossilOrigin-Name: 522502ec18bffbb8e1516de542be270a9302df1c

manifest

@@ -1,5 +1,5 @@
-C Update\sthe\sfuzztest\sdata\susing\sthe\slatest\stest\svectors\sdiscovered\sby\sAFL.
-D 2015-06-20T14:11:56.166
+C Split\sout\sall\sfour\scases\sof\scellSizePtr()\sinto\sdifferent\smethods,\seach\soptimized\nfor\sthe\sspecific\spage\stype.\s\sThis\sgives\sa\s0.36%\sperformance\sincrease\sat\sa\scost\nof\sabout\s300\sbytes\sof\scode.
+D 2015-06-20T18:13:59.692
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in 1063c58075b7400d93326b0eb332b48a54f53025
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -192,7 +192,7 @@ F src/auth.c b56c78ebe40a2110fd361379f7e8162d23f92240
 F src/backup.c ff743689c4d6c5cb55ad42ed9d174b2b3e71f1e3
 F src/bitvec.c 5eb7958c3bf65210211cbcfc44eff86d0ded7c9d
 F src/btmutex.c 45a968cc85afed9b5e6cf55bf1f42f8d18107f79
-F src/btree.c 173c2ba1b8cf941971683f584965369791125f12
+F src/btree.c a311c31f1d8da477c37ae7217ea6624312b2148d
 F src/btree.h 969adc948e89e449220ff0ff724c94bb2a52e9f1
 F src/btreeInt.h 6ece2dd9c8e2eac05f0a8ded8772a44e96486c65
 F src/build.c b3f15255d5b16e42dafeaa638fd4f8a47c94ed70
@@ -1286,7 +1286,10 @@ F tool/vdbe_profile.tcl 67746953071a9f8f2f668b73fe899074e2c6d8c1
 F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4
 F tool/warnings.sh 48bd54594752d5be3337f12c72f28d2080cb630b
 F tool/win/sqlite.vsix deb315d026cc8400325c5863eef847784a219a2f
-P 7cdbae625eb029538a693d2bebec465a6f65fb90
-R 5add07a39efb3611e2cfa0ac20a2c5f5
+P b97f9cf73e503c7285ba3a801e1f932f222d96b2
+R abd877b06a45970f5668a06bcf76a6b3
+T *branch * btree-opt
+T *sym-btree-opt *
+T -sym-trunk *
 U drh
-Z 71db4d574368380e4b14cadc01f6d8d0
+Z 3e76e6635cfc3906ab35c190cf944ecd

manifest.uuid

@@ -1 +1 @@
-b97f9cf73e503c7285ba3a801e1f932f222d96b2
+522502ec18bffbb8e1516de542be270a9302df1c

src/btree.c

@@ -1175,10 +1175,12 @@ static void btreeParseCell(
 ** the space used by the cell pointer.
 **
 ** cellSizePtrNoPayload()    =>   table internal nodes
-** cellSizePtr()             =>   all index nodes & table leaf nodes
+** cellSizeTableLeaf()       =>   table leaf nodes
+** cellSizeIndexInternal()   =>   internal index nodes
+** cellSizeIndexLeaf()       =>   leaf index nodes
 */
-static u16 cellSizePtr(MemPage *pPage, u8 *pCell){
-  u8 *pIter = pCell + pPage->childPtrSize; /* For looping over bytes of pCell */
+static u16 cellSizeTableLeaf(MemPage *pPage, u8 *pCell){
+  u8 *pIter = pCell;                       /* For looping over bytes of pCell */
   u8 *pEnd;                                /* End mark for a varint */
   u32 nSize;                               /* Size value to return */
 
@@ -1192,6 +1194,7 @@ static u16 cellSizePtr(MemPage *pPage, u8 *pCell){
 #endif
 
   assert( pPage->noPayload==0 );
+  assert( pPage->childPtrSize==0 );
   nSize = *pIter;
   if( nSize>=0x80 ){
     pEnd = &pIter[8];
@@ -1201,13 +1204,12 @@ static u16 cellSizePtr(MemPage *pPage, u8 *pCell){
     }while( *(pIter)>=0x80 && pIter<pEnd );
   }
   pIter++;
-  if( pPage->intKey ){
-    /* pIter now points at the 64-bit integer key value, a variable length 
-    ** integer. The following block moves pIter to point at the first byte
-    ** past the end of the key value. */
-    pEnd = &pIter[9];
-    while( (*pIter++)&0x80 && pIter<pEnd );
-  }
+  assert( pPage->intKey );
+  /* pIter now points at the 64-bit integer key value, a variable length 
+  ** integer. The following block moves pIter to point at the first byte
+  ** past the end of the key value. */
+  pEnd = &pIter[9];
+  while( (*pIter++)&0x80 && pIter<pEnd );
   testcase( nSize==pPage->maxLocal );
   testcase( nSize==pPage->maxLocal+1 );
   if( nSize<=pPage->maxLocal ){
@@ -1226,6 +1228,94 @@ static u16 cellSizePtr(MemPage *pPage, u8 *pCell){
   assert( nSize==debuginfo.nSize || CORRUPT_DB );
   return (u16)nSize;
 }
+static u16 cellSizeIndexLeaf(MemPage *pPage, u8 *pCell){
+  u8 *pIter = pCell;                       /* For looping over bytes of pCell */
+  u8 *pEnd;                                /* End mark for a varint */
+  u32 nSize;                               /* Size value to return */
+
+#ifdef SQLITE_DEBUG
+  /* The value returned by this function should always be the same as
+  ** the (CellInfo.nSize) value found by doing a full parse of the
+  ** cell. If SQLITE_DEBUG is defined, an assert() at the bottom of
+  ** this function verifies that this invariant is not violated. */
+  CellInfo debuginfo;
+  pPage->xParseCell(pPage, pCell, &debuginfo);
+#endif
+
+  assert( pPage->noPayload==0 );
+  assert( pPage->childPtrSize==0 );
+  nSize = *pIter;
+  if( nSize>=0x80 ){
+    pEnd = &pIter[8];
+    nSize &= 0x7f;
+    do{
+      nSize = (nSize<<7) | (*++pIter & 0x7f);
+    }while( *(pIter)>=0x80 && pIter<pEnd );
+  }
+  pIter++;
+  assert( pPage->intKey==0 );
+  testcase( nSize==pPage->maxLocal );
+  testcase( nSize==pPage->maxLocal+1 );
+  if( nSize<=pPage->maxLocal ){
+    nSize += (u32)(pIter - pCell);
+    if( nSize<4 ) nSize = 4;
+  }else{
+    int minLocal = pPage->minLocal;
+    nSize = minLocal + (nSize - minLocal) % (pPage->pBt->usableSize - 4);
+    testcase( nSize==pPage->maxLocal );
+    testcase( nSize==pPage->maxLocal+1 );
+    if( nSize>pPage->maxLocal ){
+      nSize = minLocal;
+    }
+    nSize += 4 + (u16)(pIter - pCell);
+  }
+  assert( nSize==debuginfo.nSize || CORRUPT_DB );
+  return (u16)nSize;
+}
+static u16 cellSizePtrIndexInternal(MemPage *pPage, u8 *pCell){
+  u8 *pIter = pCell + 4;                   /* For looping over bytes of pCell */
+  u8 *pEnd;                                /* End mark for a varint */
+  u32 nSize;                               /* Size value to return */
+
+#ifdef SQLITE_DEBUG
+  /* The value returned by this function should always be the same as
+  ** the (CellInfo.nSize) value found by doing a full parse of the
+  ** cell. If SQLITE_DEBUG is defined, an assert() at the bottom of
+  ** this function verifies that this invariant is not violated. */
+  CellInfo debuginfo;
+  pPage->xParseCell(pPage, pCell, &debuginfo);
+#endif
+
+  assert( pPage->childPtrSize==4 );
+  assert( pPage->noPayload==0 );
+  nSize = *pIter;
+  if( nSize>=0x80 ){
+    pEnd = &pIter[8];
+    nSize &= 0x7f;
+    do{
+      nSize = (nSize<<7) | (*++pIter & 0x7f);
+    }while( *(pIter)>=0x80 && pIter<pEnd );
+  }
+  pIter++;
+  assert( pPage->intKey==0 );
+  testcase( nSize==pPage->maxLocal );
+  testcase( nSize==pPage->maxLocal+1 );
+  if( nSize<=pPage->maxLocal ){
+    nSize += (u32)(pIter - pCell);
+    assert( nSize>=4 );
+  }else{
+    int minLocal = pPage->minLocal;
+    nSize = minLocal + (nSize - minLocal) % (pPage->pBt->usableSize - 4);
+    testcase( nSize==pPage->maxLocal );
+    testcase( nSize==pPage->maxLocal+1 );
+    if( nSize>pPage->maxLocal ){
+      nSize = minLocal;
+    }
+    nSize += 4 + (u16)(pIter - pCell);
+  }
+  assert( nSize==debuginfo.nSize || CORRUPT_DB );
+  return (u16)nSize;
+}
 static u16 cellSizePtrNoPayload(MemPage *pPage, u8 *pCell){
   u8 *pIter = pCell + 4; /* For looping over bytes of pCell */
   u8 *pEnd;              /* End mark for a varint */
@@ -1633,7 +1723,6 @@ static int decodeFlags(MemPage *pPage, int flagByte){
   pPage->leaf = (u8)(flagByte>>3);  assert( PTF_LEAF == 1<<3 );
   flagByte &= ~PTF_LEAF;
   pPage->childPtrSize = 4-4*pPage->leaf;
-  pPage->xCellSize = cellSizePtr;
   pBt = pPage->pBt;
   if( flagByte==(PTF_LEAFDATA | PTF_INTKEY) ){
     /* EVIDENCE-OF: R-03640-13415 A value of 5 means the page is an interior
@@ -1646,6 +1735,7 @@ static int decodeFlags(MemPage *pPage, int flagByte){
     if( pPage->leaf ){
       pPage->intKeyLeaf = 1;
       pPage->noPayload = 0;
+      pPage->xCellSize = cellSizeTableLeaf;
       pPage->xParseCell = btreeParseCellPtr;
     }else{
       pPage->intKeyLeaf = 0;
@@ -1668,6 +1758,11 @@ static int decodeFlags(MemPage *pPage, int flagByte){
     pPage->xParseCell = btreeParseCellPtrIndex;
     pPage->maxLocal = pBt->maxLocal;
     pPage->minLocal = pBt->minLocal;
+    if( pPage->leaf ){
+      pPage->xCellSize = cellSizeIndexLeaf;
+    }else{
+      pPage->xCellSize = cellSizePtrIndexInternal;
+    }
   }else{
     /* EVIDENCE-OF: R-47608-56469 Any other value for the b-tree page type is
     ** an error. */