From: drh <drh@noemail.net>
Date: Tue, 1 Apr 2008 00:36:10 +0000 (+0000)
Subject: Break up the implementation of OP_Move, OP_Copy, and OP_SCopy to reduce
X-Git-Tag: version-3.6.10~1232
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=e1349cb0f0d2178fa584d2e16dde7b35eeefcbd0;p=thirdparty%2Fsqlite.git

Break up the implementation of OP_Move, OP_Copy, and OP_SCopy to reduce
the number of branch instructions. (CVS 4945)

FossilOrigin-Name: 53e533d3a764d1973c24bffaacc505ea4b61a2b9
---

diff --git a/manifest b/manifest
index a49a7e5251..71cda47697 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Add\sthe\sveryquick.test\sscript\sfor\sa\svery\sfast\soverview\stest\sthat\somits\nall\si/o\sand\smalloc\stesting.\s(CVS\s4944)
-D 2008-03-31T23:51:35
+C Break\sup\sthe\simplementation\sof\sOP_Move,\sOP_Copy,\sand\sOP_SCopy\sto\sreduce\nthe\snumber\sof\sbranch\sinstructions.\s(CVS\s4945)
+D 2008-04-01T00:36:10
 F Makefile.arm-wince-mingw32ce-gcc ac5f7b2cef0cd850d6f755ba6ee4ab961b1fadf7
 F Makefile.in cf434ce8ca902e69126ae0f94fc9f7dc7428a5fa
 F Makefile.linux-gcc d53183f4aa6a9192d249731c90dbdffbd2c68654
@@ -174,7 +174,7 @@ F src/update.c e23e83cf481b25d5fc7beb92efbb71d297712fd3
 F src/utf.c 8c94fa10efc78c2568d08d436acc59df4df7191b
 F src/util.c dba9e04121eb17ec4643d6ca231ff859452cf0e2
 F src/vacuum.c 3524411bfb58aac0d87eadd3e5b7cd532772af30
-F src/vdbe.c 07f500db3880a8555f7d76ef5f3cc405725ae9b8
+F src/vdbe.c 1a8f3ececaa93d4932d27ba87946a6907625338c
 F src/vdbe.h f72201a0657d5f3d6cc008d1f8d9cc65768518c9
 F src/vdbeInt.h 0b96efdeecb0803e504bf1c16b198f87c91d6019
 F src/vdbeapi.c ab6e99f8a6b7fcb82c2c698da7a36762a7593f0a
@@ -620,7 +620,7 @@ F www/tclsqlite.tcl 8be95ee6dba05eabcd27a9d91331c803f2ce2130
 F www/vdbe.tcl 87a31ace769f20d3627a64fa1fade7fed47b90d0
 F www/version3.tcl 890248cf7b70e60c383b0e84d77d5132b3ead42b
 F www/whentouse.tcl fc46eae081251c3c181bd79c5faef8195d7991a5
-P c29ee0fed23dcdbd9dde6b1e42b603100ea2389c
-R ea5dee7bb1231c90f372bc524dc68887
+P f61df8daa89f07dad2a0ded00c326ef35dead257
+R 70671ac2da4a3b5255caf0a8bf9dc874
 U drh
-Z 9099251370f41c7219918acc2b43b496
+Z cb426daa3c0350483da8130288b38568
diff --git a/manifest.uuid b/manifest.uuid
index b195260ad3..8ffb8a4ad3 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-f61df8daa89f07dad2a0ded00c326ef35dead257
\ No newline at end of file
+53e533d3a764d1973c24bffaacc505ea4b61a2b9
\ No newline at end of file
diff --git a/src/vdbe.c b/src/vdbe.c
index f969bbcd56..b9e2d1aa41 100644
--- a/src/vdbe.c
+++ b/src/vdbe.c
@@ -43,7 +43,7 @@
 ** in this file for details.  If in doubt, do not deviate from existing
 ** commenting and indentation practices when changing or adding code.
 **
-** $Id: vdbe.c,v 1.723 2008/03/31 18:19:54 drh Exp $
+** $Id: vdbe.c,v 1.724 2008/04/01 00:36:10 drh Exp $
 */
 #include "sqliteInt.h"
 #include <ctype.h>
@@ -971,6 +971,24 @@ case OP_Variable: {           /* out2-prerelease */
 ** is left holding a NULL.  It is an error for P1 and P2 to be the
 ** same register.
 */
+case OP_Move: {
+  char *zMalloc;
+  assert( pOp->p1>0 );
+  assert( pOp->p1<=p->nMem );
+  pIn1 = &p->aMem[pOp->p1];
+  REGISTER_TRACE(pOp->p1, pIn1);
+  assert( pOp->p2>0 );
+  assert( pOp->p2<=p->nMem );
+  pOut = &p->aMem[pOp->p2];
+  assert( pOut!=pIn1 );
+  zMalloc = pOut->zMalloc;
+  pOut->zMalloc = 0;
+  sqlite3VdbeMemMove(pOut, pIn1);
+  pIn1->zMalloc = zMalloc;
+  REGISTER_TRACE(pOp->p2, pOut);
+  break;
+}
+
 /* Opcode: Copy P1 P2 * * *
 **
 ** Make a copy of register P1 into register P2.
@@ -978,6 +996,21 @@ case OP_Variable: {           /* out2-prerelease */
 ** This instruction makes a deep copy of the value.  A duplicate
 ** is made of any string or blob constant.  See also OP_SCopy.
 */
+case OP_Copy: {
+  assert( pOp->p1>0 );
+  assert( pOp->p1<=p->nMem );
+  pIn1 = &p->aMem[pOp->p1];
+  REGISTER_TRACE(pOp->p1, pIn1);
+  assert( pOp->p2>0 );
+  assert( pOp->p2<=p->nMem );
+  pOut = &p->aMem[pOp->p2];
+  assert( pOut!=pIn1 );
+  sqlite3VdbeMemShallowCopy(pOut, pIn1, MEM_Ephem);
+  Deephemeralize(pOut);
+  REGISTER_TRACE(pOp->p2, pOut);
+  break;
+}
+
 /* Opcode: SCopy P1 P2 * * *
 **
 ** Make a shallow copy of register P1 into register P2.
@@ -990,8 +1023,6 @@ case OP_Variable: {           /* out2-prerelease */
 ** during the lifetime of the copy.  Use OP_Copy to make a complete
 ** copy.
 */
-case OP_Move:
-case OP_Copy:
 case OP_SCopy: {
   assert( pOp->p1>0 );
   assert( pOp->p1<=p->nMem );
@@ -1001,17 +1032,7 @@ case OP_SCopy: {
   assert( pOp->p2<=p->nMem );
   pOut = &p->aMem[pOp->p2];
   assert( pOut!=pIn1 );
-  if( pOp->opcode==OP_Move ){
-    char *zMalloc = pOut->zMalloc;
-    pOut->zMalloc = 0;
-    sqlite3VdbeMemMove(pOut, pIn1);
-    pIn1->zMalloc = zMalloc;
-  }else{
-    sqlite3VdbeMemShallowCopy(pOut, pIn1, MEM_Ephem);
-    if( pOp->opcode==OP_Copy ){
-      Deephemeralize(pOut);
-    }
-  }
+  sqlite3VdbeMemShallowCopy(pOut, pIn1, MEM_Ephem);
   REGISTER_TRACE(pOp->p2, pOut);
   break;
 }