Remove the use of htonl() in the previous check-in due to linkage iss…

…ues.

Add the get2byteAligned() macro and use it for access to the cell offsets
on btree pages for about a 1% performance gain.

FossilOrigin-Name: 79ff36b7170c9e7e7a9935c8b9d1665867771087

manifest

@@ -1,5 +1,5 @@
-C Make\suse\sof\shtonl()\sand\s<nowiki>__builtin_bswap32()</nowiki>\sfor\sfaster\nimplementations\sof\ssqlite3Get4byte()\sand\ssqlite3Put4byte().
-D 2015-06-30T12:47:09.735
+C Remove\sthe\suse\sof\shtonl()\sin\sthe\sprevious\scheck-in\sdue\sto\slinkage\sissues.\nAdd\sthe\sget2byteAligned()\smacro\sand\suse\sit\sfor\saccess\sto\sthe\scell\soffsets\non\sbtree\spages\sfor\sabout\sa\s1%\sperformance\sgain.
+D 2015-06-30T13:28:18.237
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in 285a0a234ed7610d431d91671c136098c2bd86a9
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -269,9 +269,9 @@ F src/auth.c b56c78ebe40a2110fd361379f7e8162d23f92240
 F src/backup.c ff743689c4d6c5cb55ad42ed9d174b2b3e71f1e3
 F src/bitvec.c d1f21d7d91690747881f03940584f4cc548c9d3d
 F src/btmutex.c 45a968cc85afed9b5e6cf55bf1f42f8d18107f79
-F src/btree.c 08ae64b0387e72b8201981a2d7b0f58b92fdff29
+F src/btree.c 3a535c0118872c3ee4e198b80a62d09315381dab
 F src/btree.h 969adc948e89e449220ff0ff724c94bb2a52e9f1
-F src/btreeInt.h e4eabc722b1ae017ac9c266a75769d4c6a9afde6
+F src/btreeInt.h 583240896ca96ba3b371b42e8cb6bd73c9e4717f
 F src/build.c b3f15255d5b16e42dafeaa638fd4f8a47c94ed70
 F src/callback.c 7b44ce59674338ad48b0e84e7b72f935ea4f68b0
 F src/complete.c addcd8160b081131005d5bc2d34adf20c1c5c92f
@@ -388,7 +388,7 @@ F src/treeview.c c84b1a8ebc7f1d00cd76ce4958eeb3ae1021beed
 F src/trigger.c 322f23aad694e8f31d384dcfa386d52a48d3c52f
 F src/update.c 487747b328b7216bb7f6af0695d6937d5c9e605f
 F src/utf.c fc6b889ba0779b7722634cdeaa25f1930d93820c
-F src/util.c 99396e37038a68073b11bd41b041eace5c1728c2
+F src/util.c 89bfe78b4610d456ba431a0865309a20acc115f3
 F src/vacuum.c 2ddd5cad2a7b9cef7f9e431b8c7771634c6b1701
 F src/vdbe.c 5ee4a2bf871418f61d06dc256b9b3a0084b5ec46
 F src/vdbe.h 7a75045d879118b9d3af7e8b3c108f2f27c51473
@@ -1364,7 +1364,7 @@ F tool/vdbe_profile.tcl 67746953071a9f8f2f668b73fe899074e2c6d8c1
 F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4
 F tool/warnings.sh 48bd54594752d5be3337f12c72f28d2080cb630b
 F tool/win/sqlite.vsix deb315d026cc8400325c5863eef847784a219a2f
-P b406b20ecdf0bff63c5c222fab11cb9acee86765
-R 52c32250d08365fc3595da7414b917a8
+P bc27ebd7f73e9fc8e00da6ec82632e439fcce812
+R be192770615d2f155ef5ba2c23f2b23e
 U drh
-Z a9454dee991519551f365a2fb6736c41
+Z ba4fa6154f0804a80e26fea56b904f4a

manifest.uuid

@@ -1 +1 @@
-bc27ebd7f73e9fc8e00da6ec82632e439fcce812
+79ff36b7170c9e7e7a9935c8b9d1665867771087

src/btree.c

@@ -971,9 +971,9 @@ static int ptrmapGet(BtShared *pBt, Pgno key, u8 *pEType, Pgno *pPgno){
 ** This routine works only for pages that do not contain overflow cells.
 */
 #define findCell(P,I) \
-  ((P)->aData + ((P)->maskPage & get2byte(&(P)->aCellIdx[2*(I)])))
+  ((P)->aData + ((P)->maskPage & get2byteAligned(&(P)->aCellIdx[2*(I)])))
 #define findCellPastPtr(P,I) \
-  ((P)->aDataOfst + ((P)->maskPage & get2byte(&(P)->aCellIdx[2*(I)])))
+  ((P)->aDataOfst + ((P)->maskPage & get2byteAligned(&(P)->aCellIdx[2*(I)])))
 
 
 /*
@@ -1754,7 +1754,7 @@ static int btreeInitPage(MemPage *pPage){
 
       if( !pPage->leaf ) iCellLast--;
       for(i=0; i<pPage->nCell; i++){
-        pc = get2byte(&data[cellOffset+i*2]);
+        pc = get2byteAligned(&data[cellOffset+i*2]);
         testcase( pc==iCellFirst );
         testcase( pc==iCellLast );
         if( pc<iCellFirst || pc>iCellLast ){
@@ -6625,7 +6625,7 @@ static int editPage(
 #ifdef SQLITE_DEBUG
   for(i=0; i<nNew && !CORRUPT_DB; i++){
     u8 *pCell = pCArray->apCell[i+iNew];
-    int iOff = get2byte(&pPg->aCellIdx[i*2]);
+    int iOff = get2byteAligned(&pPg->aCellIdx[i*2]);
     if( pCell>=aData && pCell<&aData[pPg->pBt->usableSize] ){
       pCell = &pTmp[pCell - aData];
     }
@@ -7127,7 +7127,7 @@ static int balance_nonroot(
       memset(&b.szCell[b.nCell+limit], 0, sizeof(b.szCell[0])*pOld->nOverflow);
       limit = pOld->aiOvfl[0];
       for(j=0; j<limit; j++){
-        b.apCell[b.nCell] = aData + (maskPage & get2byte(piCell));
+        b.apCell[b.nCell] = aData + (maskPage & get2byteAligned(piCell));
         piCell += 2;
         b.nCell++;
       }
@@ -7140,7 +7140,7 @@ static int balance_nonroot(
     piEnd = aData + pOld->cellOffset + 2*pOld->nCell;
     while( piCell<piEnd ){
       assert( b.nCell<nMaxCells );
-      b.apCell[b.nCell] = aData + (maskPage & get2byte(piCell));
+      b.apCell[b.nCell] = aData + (maskPage & get2byteAligned(piCell));
       piCell += 2;
       b.nCell++;
     }
@@ -9105,7 +9105,7 @@ static int checkTreePage(
     /* EVIDENCE-OF: R-02776-14802 The cell pointer array consists of K 2-byte
     ** integer offsets to the cell contents. */
     for(i=0; i<nCell; i++){
-      int pc = get2byte(&data[cellStart+i*2]);
+      int pc = get2byteAligned(&data[cellStart+i*2]);
       u32 size = 65536;
       if( pc<=usableSize-4 ){
         size = pPage->xCellSize(pPage, &data[pc]);

src/btreeInt.h

@@ -691,3 +691,16 @@ struct IntegrityCk {
 #define put2byte(p,v) ((p)[0] = (u8)((v)>>8), (p)[1] = (u8)(v))
 #define get4byte sqlite3Get4byte
 #define put4byte sqlite3Put4byte
+
+/*
+** get2byteAligned(), unlike get2byte(), requires that its argument point to a
+** two-byte aligned address.  get2bytea() is only used for accessing the
+** cell addresses in a btree header.
+*/
+#if SQLITE_BYTEORDER==4321
+# define get2byteAligned(x)  (*(u16*)(x))
+#elif SQLITE_BYTEORDER==1234 && defined(__GNUC__)
+# define get2byteAligned(x)  __builtin_bswap16(*(u16*)(x))
+#else
+# define get2byteAligned(x)  ((x)[0]<<8 | (x)[1])
+#endif

src/util.c

@@ -1082,10 +1082,6 @@ u32 sqlite3Get4byte(const u8 *p){
   u32 x;
   memcpy(&x,p,4);
   return x;
-#elif defined(_MSC_VER)
-  u32 x;
-  memcpy(&x,p,4);
-  return htonl(x);
 #elif SQLITE_BYTEORDER==1234 && defined(__GNUC__)
   u32 x;
   memcpy(&x,p,4);
@@ -1098,9 +1094,6 @@ u32 sqlite3Get4byte(const u8 *p){
 void sqlite3Put4byte(unsigned char *p, u32 v){
 #if SQLITE_BYTEORDER==4321
   memcpy(p,&v,4);
-#elif defined(_MSC_VER)
-  u32 x = htonl(v);
-  memcpy(&x,p,4);
 #elif SQLITE_BYTEORDER==1234 && defined(__GNUC__)
   u32 x = __builtin_bswap32(v);
   memcpy(p,&x,4);