From: drh <drh@noemail.net>
Date: Wed, 14 Dec 2016 11:14:13 +0000 (+0000)
Subject: Three times faster sqlite3SrcListAppend() in the common case by avoiding the
X-Git-Tag: version-3.16.0~44
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=ac178b3d7f7db2dfdf0bd693cb36497fc6d57dd9;p=thirdparty%2Fsqlite.git

Three times faster sqlite3SrcListAppend() in the common case by avoiding the
call to sqlite3SrcListEnlarge() for the first allocation.

FossilOrigin-Name: 0ea2762f1d8f6a93ae2ee3b7b835927a474c6f66
---

diff --git a/manifest b/manifest
index 2934b2c6ef..26d50e31a5 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Fix\sthe\soptimization\sthat\sprevents\swriting\sfreelist\spages\sto\sthe\sjournal.
-D 2016-12-14T10:30:12.405
+C Three\stimes\sfaster\ssqlite3SrcListAppend()\sin\sthe\scommon\scase\sby\savoiding\sthe\ncall\sto\ssqlite3SrcListEnlarge()\sfor\sthe\sfirst\sallocation.
+D 2016-12-14T11:14:13.907
 F Makefile.in 7639c6a09da11a9c7c6f2630fc981ee588d1072d
 F Makefile.linux-gcc 7bc79876b875010e8c8f9502eb935ca92aa3c434
 F Makefile.msc b8ca53350ae545e3562403d5da2a69cec79308da
@@ -334,7 +334,7 @@ F src/btmutex.c bc87dd3b062cc26edfe79918de2200ccb8d41e73
 F src/btree.c b2055dff0b94e03eaad48a760984a2d8e39244e6
 F src/btree.h 2349a588abcd7e0c04f984e15c5c777b61637583
 F src/btreeInt.h 10c4b77c2fb399580babbcc7cf652ac10dba796e
-F src/build.c 178f16698cbcb43402c343a9413fe22c99ffee21
+F src/build.c 66bab5ee3998b1ebbea66ce0de60a82dcf497747
 F src/callback.c 2e76147783386374bf01b227f752c81ec872d730
 F src/complete.c a3634ab1e687055cd002e11b8f43eb75c17da23e
 F src/ctime.c 9f2296a4e5d26ebf0e0d95a0af4628f1ea694e7a
@@ -1536,7 +1536,7 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P c7021960f5c070fb5c9db9e41b4000d3dc065f42
-R 29a5ab173feb9dcb847f7e97678fc3f9
+P 6aa9b26544cbd0b41115c5f127dcf9a286d17e2b
+R 5c6f1d55f58a01899a13212bdf50e07f
 U drh
-Z a1e79a7a1334afe1605804fa02a1d4f0
+Z b26cd3596202cf83d05f18857a98dc5b
diff --git a/manifest.uuid b/manifest.uuid
index e16b607041..1d21ba4de4 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-6aa9b26544cbd0b41115c5f127dcf9a286d17e2b
\ No newline at end of file
+0ea2762f1d8f6a93ae2ee3b7b835927a474c6f66
\ No newline at end of file
diff --git a/src/build.c b/src/build.c
index 0fe2032689..d613e3a9e4 100644
--- a/src/build.c
+++ b/src/build.c
@@ -3736,9 +3736,12 @@ SrcList *sqlite3SrcListAppend(
     pList = sqlite3DbMallocRawNN(db, sizeof(SrcList) );
     if( pList==0 ) return 0;
     pList->nAlloc = 1;
-    pList->nSrc = 0;
+    pList->nSrc = 1;
+    memset(&pList->a[0], 0, sizeof(pList->a[0]));
+    pList->a[0].iCursor = -1;
+  }else{
+    pList = sqlite3SrcListEnlarge(db, pList, 1, pList->nSrc);
   }
-  pList = sqlite3SrcListEnlarge(db, pList, 1, pList->nSrc);
   if( db->mallocFailed ){
     sqlite3SrcListDelete(db, pList);
     return 0;