Simplification and performance improvements in sqlite3ExprDup() and its

subroutines.  More work is possible in this area.

FossilOrigin-Name: 476cc2838824e0667e80ce527b9caa551dee4a77

diff --git a/manifest b/manifest
index 8bc65f07d125fc9a9185ef1e6301a159a151eda9..c6cd43627ed5ae4e339c4bf33eecc4ac21516e81 100644 (file)
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Rename\sthe\sOP_MX_JUMP\smacro\sto\sSQLITE_MX_JUMP_OPCODE\sto\savoid\sconfusing\sthe\nopcode\sname\sgenerator.
-D 2016-04-11T16:35:05.793
+C Simplification\sand\sperformance\simprovements\sin\ssqlite3ExprDup()\sand\sits\nsubroutines.\s\sMore\swork\sis\spossible\sin\sthis\sarea.
+D 2016-04-11T16:43:43.285
 F Makefile.in eba680121821b8a60940a81454316f47a341487a
 F Makefile.linux-gcc 7bc79876b875010e8c8f9502eb935ca92aa3c434
 F Makefile.msc 1f123a0757f6f04f0341accb46457e116817159a
@@ -329,7 +329,7 @@ F src/ctime.c 60e135af364d777a9ab41c97e5e89cd224da6198
 F src/date.c 0b73e681c11fca867fec554750c07fe0d4e417c1
 F src/dbstat.c c845548d4346e606e2f2b7d2e714ace2b8a7dd1b
 F src/delete.c 78eb999114ec04fcf1b7d123ccedb4b5b734930e
-F src/expr.c 702260035c6f23051bdae7a0be28e4884b892386
+F src/expr.c 16829fcf84b41d16b3d2e74e4e30ea8315cbba88
 F src/fault.c 160a0c015b6c2629d3899ed2daf63d75754a32bb
 F src/fkey.c 4c0bd09e602b8ae8d36d81e31e4872d0b53c87bb
 F src/func.c 552d300265aed09eea21f68ac742a440550c0062
@@ -1482,7 +1482,7 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P 60ad80e3af4bae9f5c74fedf09eec9689e2e3dbf
-R f6edf7124a508a9e875e2a5fe8999259
+P e554a4c38bda9c73bf129bb7c665c53ccc4d96a8
+R ddaad63736e0e0e6322e4bbbe74f8062
 U drh
-Z 1a9da7914d71f57fbfab1a0d0fb98803
+Z db16ea712247dfbc518b4dea8f54265a

diff --git a/manifest.uuid b/manifest.uuid
index d8dad99228e6475040d00ece8c2f9244391b8b0f..c7adec1100ad86d16e81f756a483a3ecdebb0b78 100644 (file)
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-e554a4c38bda9c73bf129bb7c665c53ccc4d96a8
\ No newline at end of file
+476cc2838824e0667e80ce527b9caa551dee4a77
\ No newline at end of file

diff --git a/src/expr.c b/src/expr.c
index d11a7a87b0440ad53c8335155bc1a3dc7e4bf869..53ba58101c606248eafd0fc0ceff89b569f03a02 100644 (file)
--- a/src/expr.c
+++ b/src/expr.c
@@ -812,7 +812,7 @@ static int dupedExprStructSize(Expr *p, int flags){
   assert( flags==EXPRDUP_REDUCE || flags==0 ); /* Only one flag value allowed */
   assert( EXPR_FULLSIZE<=0xfff );
   assert( (0xfff & (EP_Reduced|EP_TokenOnly))==0 );
-  if( 0==(flags&EXPRDUP_REDUCE) ){
+  if( 0==flags ){
     nSize = EXPR_FULLSIZE;
   }else{
     assert( !ExprHasProperty(p, EP_TokenOnly|EP_Reduced) );
@@ -874,88 +874,88 @@ static int dupedExprSize(Expr *p, int flags){
 ** if any. Before returning, *pzBuffer is set to the first byte past the
 ** portion of the buffer copied into by this function.
 */
-static Expr *exprDup(sqlite3 *db, Expr *p, int flags, u8 **pzBuffer){
-  Expr *pNew = 0;                      /* Value to return */
-  assert( flags==0 || flags==EXPRDUP_REDUCE );
-  assert( db!=0 );
-  if( p ){
-    const int isReduced = (flags&EXPRDUP_REDUCE);
-    u8 *zAlloc;
-    u32 staticFlag = 0;
+static Expr *exprDup(sqlite3 *db, Expr *p, int dupFlags, u8 **pzBuffer){
+  Expr *pNew;           /* Value to return */
+  u8 *zAlloc;           /* Memory space from which to build Expr object */
+  u32 staticFlag;       /* EP_Static if space not obtained from malloc */
 
-    assert( pzBuffer==0 || isReduced );
+  assert( db!=0 );
+  assert( p );
+  assert( dupFlags==0 || dupFlags==EXPRDUP_REDUCE );
+  assert( pzBuffer==0 || dupFlags==EXPRDUP_REDUCE );
+
+  /* Figure out where to write the new Expr structure. */
+  if( pzBuffer ){
+    zAlloc = *pzBuffer;
+    staticFlag = EP_Static;
+  }else{
+    zAlloc = sqlite3DbMallocRawNN(db, dupedExprSize(p, dupFlags));
+    staticFlag = 0;
+  }
+  pNew = (Expr *)zAlloc;
 
-    /* Figure out where to write the new Expr structure. */
-    if( pzBuffer ){
-      zAlloc = *pzBuffer;
-      staticFlag = EP_Static;
+  if( pNew ){
+    /* Set nNewSize to the size allocated for the structure pointed to
+    ** by pNew. This is either EXPR_FULLSIZE, EXPR_REDUCEDSIZE or
+    ** EXPR_TOKENONLYSIZE. nToken is set to the number of bytes consumed
+    ** by the copy of the p->u.zToken string (if any).
+    */
+    const unsigned nStructSize = dupedExprStructSize(p, dupFlags);
+    const int nNewSize = nStructSize & 0xfff;
+    int nToken;
+    if( !ExprHasProperty(p, EP_IntValue) && p->u.zToken ){
+      nToken = sqlite3Strlen30(p->u.zToken) + 1;
     }else{
-      zAlloc = sqlite3DbMallocRawNN(db, dupedExprSize(p, flags));
+      nToken = 0;
     }
-    pNew = (Expr *)zAlloc;
-
-    if( pNew ){
-      /* Set nNewSize to the size allocated for the structure pointed to
-      ** by pNew. This is either EXPR_FULLSIZE, EXPR_REDUCEDSIZE or
-      ** EXPR_TOKENONLYSIZE. nToken is set to the number of bytes consumed
-      ** by the copy of the p->u.zToken string (if any).
-      */
-      const unsigned nStructSize = dupedExprStructSize(p, flags);
-      const int nNewSize = nStructSize & 0xfff;
-      int nToken;
-      if( !ExprHasProperty(p, EP_IntValue) && p->u.zToken ){
-        nToken = sqlite3Strlen30(p->u.zToken) + 1;
-      }else{
-        nToken = 0;
-      }
-      if( isReduced ){
-        assert( ExprHasProperty(p, EP_Reduced)==0 );
-        memcpy(zAlloc, p, nNewSize);
-      }else{
-        u32 nSize = (u32)exprStructSize(p);
-        memcpy(zAlloc, p, nSize);
-        if( nSize<EXPR_FULLSIZE ){ 
-          memset(&zAlloc[nSize], 0, EXPR_FULLSIZE-nSize);
-        }
+    if( dupFlags ){
+      assert( ExprHasProperty(p, EP_Reduced)==0 );
+      memcpy(zAlloc, p, nNewSize);
+    }else{
+      u32 nSize = (u32)exprStructSize(p);
+      memcpy(zAlloc, p, nSize);
+      if( nSize<EXPR_FULLSIZE ){ 
+        memset(&zAlloc[nSize], 0, EXPR_FULLSIZE-nSize);
       }
+    }
 
-      /* Set the EP_Reduced, EP_TokenOnly, and EP_Static flags appropriately. */
-      pNew->flags &= ~(EP_Reduced|EP_TokenOnly|EP_Static|EP_MemToken);
-      pNew->flags |= nStructSize & (EP_Reduced|EP_TokenOnly);
-      pNew->flags |= staticFlag;
-
-      /* Copy the p->u.zToken string, if any. */
-      if( nToken ){
-        char *zToken = pNew->u.zToken = (char*)&zAlloc[nNewSize];
-        memcpy(zToken, p->u.zToken, nToken);
-      }
+    /* Set the EP_Reduced, EP_TokenOnly, and EP_Static flags appropriately. */
+    pNew->flags &= ~(EP_Reduced|EP_TokenOnly|EP_Static|EP_MemToken);
+    pNew->flags |= nStructSize & (EP_Reduced|EP_TokenOnly);
+    pNew->flags |= staticFlag;
 
-      if( 0==((p->flags|pNew->flags) & EP_TokenOnly) ){
-        /* Fill in the pNew->x.pSelect or pNew->x.pList member. */
-        if( ExprHasProperty(p, EP_xIsSelect) ){
-          pNew->x.pSelect = sqlite3SelectDup(db, p->x.pSelect, isReduced);
-        }else{
-          pNew->x.pList = sqlite3ExprListDup(db, p->x.pList, isReduced);
-        }
-      }
+    /* Copy the p->u.zToken string, if any. */
+    if( nToken ){
+      char *zToken = pNew->u.zToken = (char*)&zAlloc[nNewSize];
+      memcpy(zToken, p->u.zToken, nToken);
+    }
 
-      /* Fill in pNew->pLeft and pNew->pRight. */
-      if( ExprHasProperty(pNew, EP_Reduced|EP_TokenOnly) ){
-        zAlloc += dupedExprNodeSize(p, flags);
-        if( ExprHasProperty(pNew, EP_Reduced) ){
-          pNew->pLeft = exprDup(db, p->pLeft, EXPRDUP_REDUCE, &zAlloc);
-          pNew->pRight = exprDup(db, p->pRight, EXPRDUP_REDUCE, &zAlloc);
-        }
-        if( pzBuffer ){
-          *pzBuffer = zAlloc;
-        }
+    if( 0==((p->flags|pNew->flags) & EP_TokenOnly) ){
+      /* Fill in the pNew->x.pSelect or pNew->x.pList member. */
+      if( ExprHasProperty(p, EP_xIsSelect) ){
+        pNew->x.pSelect = sqlite3SelectDup(db, p->x.pSelect, dupFlags);
       }else{
-        if( !ExprHasProperty(p, EP_TokenOnly) ){
-          pNew->pLeft = sqlite3ExprDup(db, p->pLeft, 0);
-          pNew->pRight = sqlite3ExprDup(db, p->pRight, 0);
-        }
+        pNew->x.pList = sqlite3ExprListDup(db, p->x.pList, dupFlags);
       }
+    }
 
+    /* Fill in pNew->pLeft and pNew->pRight. */
+    if( ExprHasProperty(pNew, EP_Reduced|EP_TokenOnly) ){
+      zAlloc += dupedExprNodeSize(p, dupFlags);
+      if( ExprHasProperty(pNew, EP_Reduced) ){
+        pNew->pLeft = p->pLeft ?
+                      exprDup(db, p->pLeft, EXPRDUP_REDUCE, &zAlloc) : 0;
+        pNew->pRight = p->pRight ?
+                       exprDup(db, p->pRight, EXPRDUP_REDUCE, &zAlloc) : 0;
+      }
+      if( pzBuffer ){
+        *pzBuffer = zAlloc;
+      }
+    }else{
+      if( !ExprHasProperty(p, EP_TokenOnly) ){
+        pNew->pLeft = sqlite3ExprDup(db, p->pLeft, 0);
+        pNew->pRight = sqlite3ExprDup(db, p->pRight, 0);
+      }
     }
   }
   return pNew;
@@ -1007,7 +1007,7 @@ static With *withDup(sqlite3 *db, With *p){
 */
 Expr *sqlite3ExprDup(sqlite3 *db, Expr *p, int flags){
   assert( flags==0 || flags==EXPRDUP_REDUCE );
-  return exprDup(db, p, flags, 0);
+  return p ? exprDup(db, p, flags, 0) : 0;
 }
 ExprList *sqlite3ExprListDup(sqlite3 *db, ExprList *p, int flags){
   ExprList *pNew;