Performance optimization in btree.c. (CVS 2990)

FossilOrigin-Name: 3e1e6affe256a950a81ad5939b628bafb8463b42

manifest

@@ -1,5 +1,5 @@
-C Code\ssize\sreductions\sin\sselect.c.\s(CVS\s2989)
-D 2006-01-22T00:42:09
+C Performance\soptimization\sin\sbtree.c.\s(CVS\s2990)
+D 2006-01-22T21:52:57
 F Makefile.in ab3ffd8d469cef4477257169b82810030a6bb967
 F Makefile.linux-gcc aee18d8a05546dcf1888bd4547e442008a49a092
 F README 9c4e2d6706bdcc3efdd773ce752a8cdab4f90028
@@ -34,7 +34,7 @@ F src/alter.c 90b779cf00489535cab6490df6dc050f40e4e874
 F src/analyze.c 7d2b7ab9a9c2fd6e55700f69064dfdd3e36d7a8a
 F src/attach.c 0081040e9a5d13669b6712e947688c10f030bfc1
 F src/auth.c 9ae84d2d94eb96195e04515715e08e85963e96c2
-F src/btree.c c6ebb78756ec98ded27a3cb6678481e0555b6b13
+F src/btree.c 9de685a11ede765542a644441340cbed32380c3d
 F src/btree.h 5663c4f43e8521546ccebc8fc95acb013b8f3184
 F src/build.c 15224e2fd348ad32b9044aaa5bdc912e4067da15
 F src/callback.c 1bf497306c32229114f826707054df7ebe10abf2
@@ -66,7 +66,7 @@ F src/pragma.c 4496cc77dc35824e1c978c3d1413b8a5a4c777d3
 F src/prepare.c 5d6f5b7194ee72cecd66cab49d15159e55d63f28
 F src/printf.c f47a2f4b5387cd2ebb12e9117a1a5d6bd9a2b812
 F src/random.c d40f8d356cecbd351ccfab6eaedd7ec1b54f5261
-F src/select.c bdfc4b1615757a75cc999a6264f791bd133c0c49
+F src/select.c 11ad28afb33bb83b655074c87557d4686c67f92f
 F src/server.c 087b92a39d883e3fa113cae259d64e4c7438bc96
 F src/shell.c 66b073375efbdee19045e7e0cd38b85f9aff71da
 F src/sqlite.h.in 492580f7e3ff71eb43193eb7bb98e2d549889ce3
@@ -344,7 +344,7 @@ F www/tclsqlite.tcl bb0d1357328a42b1993d78573e587c6dcbc964b9
 F www/vdbe.tcl 87a31ace769f20d3627a64fa1fade7fed47b90d0
 F www/version3.tcl a99cf5f6d8bd4d5537584a2b342f0fb9fa601d8b
 F www/whentouse.tcl 97e2b5cd296f7d8057e11f44427dea8a4c2db513
-P 72a067f0df5818c0fdb3b9f8af20f83bb2e1dd34
-R 7149efc6bca05d61f3d140a668bc0541
+P 3c2eee5e1f6c7d701a6d362a04cf896d44e97fd9
+R 79b2ebcd5c87d6676140e58c49de75b7
 U drh
-Z 8f5502aac66dc065c601250997c9db38
+Z fd205e297bbdc82d40fc2de1ce715a4f

manifest.uuid

@@ -1 +1 @@
-3c2eee5e1f6c7d701a6d362a04cf896d44e97fd9
+3e1e6affe256a950a81ad5939b628bafb8463b42

src/btree.c

@@ -9,7 +9,7 @@
 **    May you share freely, never taking more than you give.
 **
 *************************************************************************
-** $Id: btree.c,v 1.306 2006/01/21 12:08:54 danielk1977 Exp $
+** $Id: btree.c,v 1.307 2006/01/22 21:52:57 drh Exp $
 **
 ** This file implements a external (disk-based) database using BTrees.
 ** For a detailed discussion of BTrees, refer to
@@ -462,7 +462,8 @@ static void put4byte(unsigned char *p, u32 v){
 ** file.
 */
 #define getVarint    sqlite3GetVarint
-#define getVarint32  sqlite3GetVarint32
+/* #define getVarint32  sqlite3GetVarint32 */
+#define getVarint32(A,B)  ((*B=*(A))<=0x7f?1:sqlite3GetVarint32(A,B))
 #define putVarint    sqlite3PutVarint
 
 /* The database page the PENDING_BYTE occupies. This page is never used.
@@ -920,12 +921,16 @@ static void parseCellPtr(
   }else{
     nPayload = 0;
   }
-  n += getVarint(&pCell[n], (u64 *)&pInfo->nKey);
-  pInfo->nHeader = n;
   pInfo->nData = nPayload;
-  if( !pPage->intKey ){
-    nPayload += pInfo->nKey;
+  if( pPage->intKey ){
+    n += getVarint(&pCell[n], (u64 *)&pInfo->nKey);
+  }else{
+    u32 x;
+    n += getVarint32(&pCell[n], &x);
+    pInfo->nKey = x;
+    nPayload += x;
   }
+  pInfo->nHeader = n;
   if( nPayload<=pPage->maxLocal ){
     /* This is the (easy) common case where the entire payload fits
     ** on the local page.  No overflow is required.

src/select.c

@@ -12,7 +12,7 @@
 ** This file contains C code routines that are called by the parser
 ** to handle SELECT statements in SQLite.
 **
-** $Id: select.c,v 1.298 2006/01/22 00:42:09 drh Exp $
+** $Id: select.c,v 1.299 2006/01/22 21:52:57 drh Exp $
 */
 #include "sqliteInt.h"
 
@@ -566,7 +566,7 @@ static int selectInnerLoop(
       break;
     }
 
-    /* If any row exists in the result set, record that fact and abort.
+    /* If any row exist in the result set, record that fact and abort.
     */
     case SRT_Exists: {
       sqlite3VdbeAddOp(v, OP_MemInt, 1, iParm);