Small performance optimization in btree.c.

FossilOrigin-Name: f710cce13577788cf3b95ed7089c3af2854271ff53f0a0b7b0619f315e331eff

diff --git a/manifest b/manifest
index 4ead71ff6900ce958a24a6cb6ca771b547ce88e7..1fd11cbf2118936e32df80d775fa5af67d0c6ad7 100644 (file)
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Databases\screated\susing\ssqlite3_deserialize()\sshould\sreport\stheir\sfilename\nas\san\sempty\sstring,\snot\sas\s"x".\s\sFix\sfor\sticket\s[53043c9793715f08].
-D 2022-11-19T00:08:35.872
+C Small\sperformance\soptimization\sin\sbtree.c.
+D 2022-11-19T00:22:12.991
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@@ -576,7 +576,7 @@ F src/auth.c f4fa91b6a90bbc8e0d0f738aa284551739c9543a367071f55574681e0f24f8cf
 F src/backup.c a2891172438e385fdbe97c11c9745676bec54f518d4447090af97189fd8e52d7
 F src/bitvec.c 7c849aac407230278445cb069bebc5f89bf2ddd87c5ed9459b070a9175707b3d
 F src/btmutex.c 6ffb0a22c19e2f9110be0964d0731d2ef1c67b5f7fabfbaeb7b9dabc4b7740ca
-F src/btree.c 6321ff29261bf9726e6b231058ff21b1ccf9f441a0b718b76c37341b16fa14ce
+F src/btree.c e8fae9a95ea9561aebc41e467a9ee9ba9150ca373031e65773d62ff02d8250d2
 F src/btree.h 4fcbb0b041013071dd5e9f53c538d49916c092e6ad8842185985e5270a0792de
 F src/btreeInt.h 8ce1332edd89dfd2461d561ac10a0ab5601c8e06200cb5230596c3caaf54482e
 F src/build.c d3e43e950e4e377c1d451a4862556792acdef1faba14a03f899d30d09731c48b
@@ -2055,8 +2055,8 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P 5c669f5f399fe89998b9edba6486f2a6fe5fca789ed82e8711349c8736b293d9
-R 06e897a36d76f0b40d32a92b9dcc8859
+P ff494449efd475878c549728cc22ee9b12d13674068781747fc042a0c1bd09c8
+R 8e4332decceeea7e1973b8e5ac88e8a4
 U drh
-Z 7c255a26bf6fe056b55fba3394c16cef
+Z 80da1bc9f69008afc02dd88003bee918
 # Remove this line to create a well-formed Fossil manifest.

diff --git a/manifest.uuid b/manifest.uuid
index 668e2dc4ede7d4d82a94b99863c0f4e4ba616fb7..7e33296fdede559281e92ea87fa9cd3551551772 100644 (file)
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-ff494449efd475878c549728cc22ee9b12d13674068781747fc042a0c1bd09c8
\ No newline at end of file
+f710cce13577788cf3b95ed7089c3af2854271ff53f0a0b7b0619f315e331eff
\ No newline at end of file

diff --git a/src/btree.c b/src/btree.c
index df24b7b33c2de01c66b095f437b5107a2d9ee08c..1c6c14d4b6d62972e8df277ddd4470b090434e43 100644 (file)
--- a/src/btree.c
+++ b/src/btree.c
@@ -5495,9 +5495,25 @@ int sqlite3BtreeFirst(BtCursor *pCur, int *pRes){
 ** on success.  Set *pRes to 0 if the cursor actually points to something
 ** or set *pRes to 1 if the table is empty.
 */
+static SQLITE_NOINLINE int btreeLast(BtCursor *pCur, int *pRes){
+  int rc = moveToRoot(pCur);
+  if( rc==SQLITE_OK ){
+    assert( pCur->eState==CURSOR_VALID );
+    *pRes = 0;
+    rc = moveToRightmost(pCur);
+    if( rc==SQLITE_OK ){
+      pCur->curFlags |= BTCF_AtLast;
+    }else{
+      pCur->curFlags &= ~BTCF_AtLast;
+    }
+  }else if( rc==SQLITE_EMPTY ){
+    assert( pCur->pgnoRoot==0 || pCur->pPage->nCell==0 );
+    *pRes = 1;
+    rc = SQLITE_OK;
+  }
+  return rc;
+}
 int sqlite3BtreeLast(BtCursor *pCur, int *pRes){
-  int rc;
- 
   assert( cursorOwnsBtShared(pCur) );
   assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
 
@@ -5518,23 +5534,7 @@ int sqlite3BtreeLast(BtCursor *pCur, int *pRes){
     *pRes = 0;
     return SQLITE_OK;
   }
-
-  rc = moveToRoot(pCur);
-  if( rc==SQLITE_OK ){
-    assert( pCur->eState==CURSOR_VALID );
-    *pRes = 0;
-    rc = moveToRightmost(pCur);
-    if( rc==SQLITE_OK ){
-      pCur->curFlags |= BTCF_AtLast;
-    }else{
-      pCur->curFlags &= ~BTCF_AtLast;
-    }
-  }else if( rc==SQLITE_EMPTY ){
-    assert( pCur->pgnoRoot==0 || pCur->pPage->nCell==0 );
-    *pRes = 1;
-    rc = SQLITE_OK;
-  }
-  return rc;
+  return btreeLast(pCur, pRes);
 }
 
 /* Move the cursor so that it points to an entry in a table (a.k.a INTKEY)