Additional refinements to Expr handling. Restore compression of trigger

expressions.  Change Expr.zToken to Expr.u.zToken and added Expr.u.iValue.
Remove an unnecessary ExprDup from CHECK constraint processing.  And so forth. (CVS 6682)

FossilOrigin-Name: 4ac2bdfbb4230b6ceaae87e738fa61036bbe03cb

1 files changed, 18 insertions, 16 deletions

diff --git a/src/resolve.c b/src/resolve.c
index b9c7face3..015fe4bf7 100644
--- a/src/resolve.c
+++ b/src/resolve.c
@@ -14,7 +14,7 @@
 ** resolve all identifiers by associating them with a particular
 ** table and column.
 **
-** $Id: resolve.c,v 1.23 2009/05/27 10:31:29 drh Exp $
+** $Id: resolve.c,v 1.24 2009/05/28 01:00:55 drh Exp $
 */
 #include "sqliteInt.h"
 #include <stdlib.h>
@@ -72,15 +72,15 @@ static void resolveAlias(
     }
     pDup->iTable = pEList->a[iCol].iAlias;
   }else{
-    char *zToken = pOrig->zToken;
-    pOrig->zToken = 0;
+    char *zToken = pOrig->u.zToken;
+    pOrig->u.zToken = 0;
     pDup = sqlite3ExprDup(db, pOrig, 0);
-    pOrig->zToken = zToken;
+    pOrig->u.zToken = zToken;
     if( pDup==0 ) return;
     if( zToken ){
       assert( (pDup->flags & (EP_Reduced|EP_TokenOnly))==0 );
-      pDup->flags2 |= EP2_FreeToken;
-      pDup->zToken = sqlite3DbStrDup(db, zToken);
+      pDup->flags2 |= EP2_MallocedToken;
+      pDup->u.zToken = sqlite3DbStrDup(db, zToken);
     }
   }
   if( pExpr->flags & EP_ExpCollate ){
@@ -138,10 +138,12 @@ static int lookupName(
 
   assert( pNC );     /* the name context cannot be NULL. */
   assert( zCol );    /* The Z in X.Y.Z cannot be NULL */
+  assert( ~ExprHasAnyProperty(pExpr, EP_TokenOnly|EP_Reduced) );
 
   /* Initialize the node to no-match */
   pExpr->iTable = -1;
   pExpr->pTab = 0;
+  ExprSetIrreducible(pExpr);
 
   /* Start at the inner-most context and move outward until a match is found */
   while( pNC && cnt==0 ){
@@ -439,7 +441,7 @@ static int resolveExprStep(Walker *pWalker, Expr *pExpr){
     /* A lone identifier is the name of a column.
     */
     case TK_ID: {
-      lookupName(pParse, 0, 0, pExpr->zToken, pNC, pExpr);
+      lookupName(pParse, 0, 0, pExpr->u.zToken, pNC, pExpr);
       return WRC_Prune;
     }
   
@@ -456,13 +458,13 @@ static int resolveExprStep(Walker *pWalker, Expr *pExpr){
       pRight = pExpr->pRight;
       if( pRight->op==TK_ID ){
         zDb = 0;
-        zTable = pExpr->pLeft->zToken;
-        zColumn = pRight->zToken;
+        zTable = pExpr->pLeft->u.zToken;
+        zColumn = pRight->u.zToken;
       }else{
         assert( pRight->op==TK_DOT );
-        zDb = pExpr->pLeft->zToken;
-        zTable = pRight->pLeft->zToken;
-        zColumn = pRight->pRight->zToken;
+        zDb = pExpr->pLeft->u.zToken;
+        zTable = pRight->pLeft->u.zToken;
+        zColumn = pRight->pRight->u.zToken;
       }
       lookupName(pParse, zDb, zTable, zColumn, pNC, pExpr);
       return WRC_Prune;
@@ -484,7 +486,7 @@ static int resolveExprStep(Walker *pWalker, Expr *pExpr){
       u8 enc = ENC(pParse->db);   /* The database encoding */
 
       assert( !ExprHasProperty(pExpr, EP_xIsSelect) );
-      zId = pExpr->zToken;
+      zId = pExpr->u.zToken;
       nId = sqlite3Strlen30(zId);
       pDef = sqlite3FindFunction(pParse->db, zId, nId, n, enc, 0);
       if( pDef==0 ){
@@ -586,8 +588,8 @@ static int resolveAsName(
 ){
   int i;             /* Loop counter */
 
-  if( pE->op==TK_ID || (pE->op==TK_STRING && pE->zToken[0]!='\'') ){
-    char *zCol = pE->zToken;
+  if( pE->op==TK_ID || (pE->op==TK_STRING && pE->u.zToken[0]!='\'') ){
+    char *zCol = pE->u.zToken;
     for(i=0; i<pEList->nExpr; i++){
       char *zAs = pEList->a[i].zName;
       if( zAs!=0 && sqlite3StrICmp(zAs, zCol)==0 ){
@@ -748,7 +750,7 @@ static int resolveCompoundOrderBy(
         if( pE==0 ) return 1;
         pE->pColl = pColl;
         pE->flags |= EP_IntValue | flags;
-        pE->iTable = iCol;
+        pE->u.iValue = iCol;
         pItem->iCol = (u16)iCol;
         pItem->done = 1;
       }else{