/ Check-in [8a6ea455]
Login
Home Timeline Branches Tags Tickets Wiki More...

Many hyperlinks are disabled.
Use anonymous login to enable hyperlinks.

Overview
Comment:Add the EP_Leaf flag bit to the Expr.flags field to indicate Expr nodes that do not have substructure. Use that bit to avoid unnecessary recursion.
Downloads: Tarball | ZIP archive | SQL archive
Timelines: family | ancestors | descendants | both | trunk
Files: files | file ages | folders
SHA1: 8a6ea455cd1bf42ae0a7f1f1789baf88d782db13
User & Date: drh 2016-09-23 21:36:24
Context
2016-09-24
01:41
Add -DSQLITE_MAX_EXPR_DEPTH=0 to the --lean option on speed-check.sh. check-in: a8cb1390 user: drh tags: trunk
2016-09-23
21:36
Add the EP_Leaf flag bit to the Expr.flags field to indicate Expr nodes that do not have substructure. Use that bit to avoid unnecessary recursion. check-in: 8a6ea455 user: drh tags: trunk
20:59
Use sqlite3ExprAlloc() instead of sqlite3PExpr() for leaf nodes in the expression tree, where appropriate. This is both smaller and faster. check-in: afac0709 user: drh tags: trunk
Changes
Hide Diffs Unified Diffs Ignore Whitespace Patch

Changes to src/attach.c. 

526
527
528
529
530
531
532
533
534
535
536
537
538
539
540

      if( pFix->pParse->db->init.busy ){
        pExpr->op = TK_NULL;
      }else{
        sqlite3ErrorMsg(pFix->pParse, "%s cannot use variables", pFix->zType);
        return 1;
      }
    }
    if( ExprHasProperty(pExpr, EP_TokenOnly) ) break;
    if( ExprHasProperty(pExpr, EP_xIsSelect) ){
      if( sqlite3FixSelect(pFix, pExpr->x.pSelect) ) return 1;
    }else{
      if( sqlite3FixExprList(pFix, pExpr->x.pList) ) return 1;
    }
    if( sqlite3FixExpr(pFix, pExpr->pRight) ){
      return 1;








|








526
527
528
529
530
531
532
533
534
535
536
537
538
539
540

      if( pFix->pParse->db->init.busy ){
        pExpr->op = TK_NULL;
      }else{
        sqlite3ErrorMsg(pFix->pParse, "%s cannot use variables", pFix->zType);
        return 1;
      }
    }
    if( ExprHasProperty(pExpr, EP_TokenOnly|EP_Leaf) ) break;
    if( ExprHasProperty(pExpr, EP_xIsSelect) ){
      if( sqlite3FixSelect(pFix, pExpr->x.pSelect) ) return 1;
    }else{
      if( sqlite3FixExprList(pFix, pExpr->x.pList) ) return 1;
    }
    if( sqlite3FixExpr(pFix, pExpr->pRight) ){
      return 1;

Changes to src/expr.c. 

1012
1013
1014
1015
1016
1017
1018

1019






1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030

1031
1032
1033
1034
1035
1036
1037
....
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236

/*
** Recursively delete an expression tree.
*/
static SQLITE_NOINLINE void sqlite3ExprDeleteNN(sqlite3 *db, Expr *p){
  assert( p!=0 );
  /* Sanity check: Assert that the IntValue is non-negative if it exists */
  assert( !ExprHasProperty(p, EP_IntValue) || p->u.iValue>=0 );

  if( !ExprHasProperty(p, EP_TokenOnly) ){






    /* The Expr.x union is never used at the same time as Expr.pRight */
    assert( p->x.pList==0 || p->pRight==0 );
    if( p->pLeft && p->op!=TK_SELECT_COLUMN ) sqlite3ExprDeleteNN(db, p->pLeft);
    sqlite3ExprDelete(db, p->pRight);
    if( ExprHasProperty(p, EP_MemToken) ) sqlite3DbFree(db, p->u.zToken);
    if( ExprHasProperty(p, EP_xIsSelect) ){
      sqlite3SelectDelete(db, p->x.pSelect);
    }else{
      sqlite3ExprListDelete(db, p->x.pList);
    }
  }

  if( !ExprHasProperty(p, EP_Static) ){
    sqlite3DbFree(db, p);
  }
}
void sqlite3ExprDelete(sqlite3 *db, Expr *p){
  if( p ) sqlite3ExprDeleteNN(db, p);
}
................................................................................

    /* Copy the p->u.zToken string, if any. */
    if( nToken ){
      char *zToken = pNew->u.zToken = (char*)&zAlloc[nNewSize];
      memcpy(zToken, p->u.zToken, nToken);
    }

    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{
        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) ){
        if( pNew->op==TK_SELECT_COLUMN ){
          pNew->pLeft = p->pLeft;
        }else{
          pNew->pLeft = sqlite3ExprDup(db, p->pLeft, 0);
        }
        pNew->pRight = sqlite3ExprDup(db, p->pRight, 0);
      }








>
|
>
>
>
>
>
>




<






>







 







|











|









|








1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030

1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
....
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243

/*
** Recursively delete an expression tree.
*/
static SQLITE_NOINLINE void sqlite3ExprDeleteNN(sqlite3 *db, Expr *p){
  assert( p!=0 );
  /* Sanity check: Assert that the IntValue is non-negative if it exists */
  assert( !ExprHasProperty(p, EP_IntValue) || p->u.iValue>=0 );
#ifdef SQLITE_DEBUG
  if( ExprHasProperty(p, EP_Leaf) && !ExprHasProperty(p, EP_TokenOnly) ){
    assert( p->pLeft==0 );
    assert( p->pRight==0 );
    assert( p->x.pSelect==0 );
  }
#endif
  if( !ExprHasProperty(p, (EP_TokenOnly|EP_Leaf)) ){
    /* The Expr.x union is never used at the same time as Expr.pRight */
    assert( p->x.pList==0 || p->pRight==0 );
    if( p->pLeft && p->op!=TK_SELECT_COLUMN ) sqlite3ExprDeleteNN(db, p->pLeft);
    sqlite3ExprDelete(db, p->pRight);

    if( ExprHasProperty(p, EP_xIsSelect) ){
      sqlite3SelectDelete(db, p->x.pSelect);
    }else{
      sqlite3ExprListDelete(db, p->x.pList);
    }
  }
  if( ExprHasProperty(p, EP_MemToken) ) sqlite3DbFree(db, p->u.zToken);
  if( !ExprHasProperty(p, EP_Static) ){
    sqlite3DbFree(db, p);
  }
}
void sqlite3ExprDelete(sqlite3 *db, Expr *p){
  if( p ) sqlite3ExprDeleteNN(db, p);
}
................................................................................

    /* Copy the p->u.zToken string, if any. */
    if( nToken ){
      char *zToken = pNew->u.zToken = (char*)&zAlloc[nNewSize];
      memcpy(zToken, p->u.zToken, nToken);
    }

    if( 0==((p->flags|pNew->flags) & (EP_TokenOnly|EP_Leaf)) ){
      /* 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{
        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_TokenOnly|EP_Leaf) ){
        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|EP_Leaf) ){
        if( pNew->op==TK_SELECT_COLUMN ){
          pNew->pLeft = p->pLeft;
        }else{
          pNew->pLeft = sqlite3ExprDup(db, p->pLeft, 0);
        }
        pNew->pRight = sqlite3ExprDup(db, p->pRight, 0);
      }

Changes to src/parse.y. 

850
851
852
853
854
855
856

857
858
859
860
861
862
863

  ** new Expr to populate pOut.  Set the span of pOut to be the identifier
  ** that created the expression.
  */
  static void spanExpr(ExprSpan *pOut, Parse *pParse, int op, Token t){
    pOut->pExpr = sqlite3ExprAlloc(pParse->db, op, &t, 1);
    pOut->zStart = t.z;
    pOut->zEnd = &t.z[t.n];

  }
}

expr(A) ::= term(A).
expr(A) ::= LP(B) expr(X) RP(E).
            {spanSet(&A,&B,&E); /*A-overwrites-B*/  A.pExpr = X.pExpr;}
term(A) ::= NULL(X).        {spanExpr(&A,pParse,@X,X);/*A-overwrites-X*/}








>








850
851
852
853
854
855
856
857
858
859
860
861
862
863
864

  ** new Expr to populate pOut.  Set the span of pOut to be the identifier
  ** that created the expression.
  */
  static void spanExpr(ExprSpan *pOut, Parse *pParse, int op, Token t){
    pOut->pExpr = sqlite3ExprAlloc(pParse->db, op, &t, 1);
    pOut->zStart = t.z;
    pOut->zEnd = &t.z[t.n];
    if( pOut->pExpr ) pOut->pExpr->flags |= EP_Leaf;
  }
}

expr(A) ::= term(A).
expr(A) ::= LP(B) expr(X) RP(E).
            {spanSet(&A,&B,&E); /*A-overwrites-B*/  A.pExpr = X.pExpr;}
term(A) ::= NULL(X).        {spanExpr(&A,pParse,@X,X);/*A-overwrites-X*/}

Changes to src/sqliteInt.h. 

2334
2335
2336
2337
2338
2339
2340

2341
2342
2343
2344
2345
2346
2347

#define EP_MemToken  0x010000 /* Need to sqlite3DbFree() Expr.zToken */
#define EP_NoReduce  0x020000 /* Cannot EXPRDUP_REDUCE this Expr */
#define EP_Unlikely  0x040000 /* unlikely() or likelihood() function */
#define EP_ConstFunc 0x080000 /* A SQLITE_FUNC_CONSTANT or _SLOCHNG function */
#define EP_CanBeNull 0x100000 /* Can be null despite NOT NULL constraint */
#define EP_Subquery  0x200000 /* Tree contains a TK_SELECT operator */
#define EP_Alias     0x400000 /* Is an alias for a result set column */


/*
** Combinations of two or more EP_* flags
*/
#define EP_Propagate (EP_Collate|EP_Subquery) /* Propagate these bits up tree */

/*








>








2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348

#define EP_MemToken  0x010000 /* Need to sqlite3DbFree() Expr.zToken */
#define EP_NoReduce  0x020000 /* Cannot EXPRDUP_REDUCE this Expr */
#define EP_Unlikely  0x040000 /* unlikely() or likelihood() function */
#define EP_ConstFunc 0x080000 /* A SQLITE_FUNC_CONSTANT or _SLOCHNG function */
#define EP_CanBeNull 0x100000 /* Can be null despite NOT NULL constraint */
#define EP_Subquery  0x200000 /* Tree contains a TK_SELECT operator */
#define EP_Alias     0x400000 /* Is an alias for a result set column */
#define EP_Leaf      0x800000 /* Expr.pLeft, .pRight, .u.pSelect all NULL */

/*
** Combinations of two or more EP_* flags
*/
#define EP_Propagate (EP_Collate|EP_Subquery) /* Propagate these bits up tree */

/*

Changes to src/walker.c. 

37
38
39
40
41
42
43
44


45
46
47
48
49
50
51

** and WRC_Continue to continue.
*/
static SQLITE_NOINLINE int walkExpr(Walker *pWalker, Expr *pExpr){
  int rc;
  testcase( ExprHasProperty(pExpr, EP_TokenOnly) );
  testcase( ExprHasProperty(pExpr, EP_Reduced) );
  rc = pWalker->xExprCallback(pWalker, pExpr);
  if( rc || ExprHasProperty(pExpr,EP_TokenOnly) ) return rc & WRC_Abort;


  if( pExpr->pLeft && walkExpr(pWalker, pExpr->pLeft) ) return WRC_Abort;
  if( pExpr->pRight && walkExpr(pWalker, pExpr->pRight) ) return WRC_Abort;
  if( ExprHasProperty(pExpr, EP_xIsSelect) ){
    if( sqlite3WalkSelect(pWalker, pExpr->x.pSelect) ) return WRC_Abort;
  }else if( pExpr->x.pList ){
    if( sqlite3WalkExprList(pWalker, pExpr->x.pList) ) return WRC_Abort;
  }








|
>
>








37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53

** and WRC_Continue to continue.
*/
static SQLITE_NOINLINE int walkExpr(Walker *pWalker, Expr *pExpr){
  int rc;
  testcase( ExprHasProperty(pExpr, EP_TokenOnly) );
  testcase( ExprHasProperty(pExpr, EP_Reduced) );
  rc = pWalker->xExprCallback(pWalker, pExpr);
  if( rc || ExprHasProperty(pExpr,(EP_TokenOnly|EP_Leaf)) ){
    return rc & WRC_Abort;
  }
  if( pExpr->pLeft && walkExpr(pWalker, pExpr->pLeft) ) return WRC_Abort;
  if( pExpr->pRight && walkExpr(pWalker, pExpr->pRight) ) return WRC_Abort;
  if( ExprHasProperty(pExpr, EP_xIsSelect) ){
    if( sqlite3WalkSelect(pWalker, pExpr->x.pSelect) ) return WRC_Abort;
  }else if( pExpr->x.pList ){
    if( sqlite3WalkExprList(pWalker, pExpr->x.pList) ) return WRC_Abort;
  }

This page was generated in about 0.02s by Fossil 2.9 [5b6be64760] 2019-06-14 00:24:04