NOT elimination moved in parsing (suggested by Monty)

sql/item_cmpfunc.cc

@@ -2030,15 +2030,6 @@ void Item_cond::neg_arguments(THD *thd)
     {
       if (!(new_item= new Item_func_not(item)))
 	return;					// Fatal OEM error
-      /*
-	We can use 0 as tables list because Item_func_not do not use it
-	on fix_fields and its arguments are already fixed.
-
-	We do not check results of fix_fields, because there are not way
-	to return error in this functions interface, thd->net.report_error
-	will be checked on upper level call.
-      */
-      new_item->fix_fields(thd, 0, &new_item);
     }
     VOID(li.replace(new_item));
   }
@@ -2734,18 +2725,6 @@ Item *Item_func_not::neg_transformer(THD *thd)	/* NOT(x)  ->  x */
 Item *Item_bool_rowready_func2::neg_transformer(THD *thd)
 {
   Item *item= negated_item();
-  if (item)
-  {
-    /*
-      We can use 0 as tables list because Item_func* family do not use it
-      on fix_fields and its arguments are already fixed.
-      
-      We do not check results of fix_fields, because there are not way
-      to return error in this functions interface, thd->net.report_error
-      will be checked on upper level call.
-    */
-    item->fix_fields(thd, 0, &item);
-  }
   return item;
 }
 
@@ -2754,9 +2733,6 @@ Item *Item_bool_rowready_func2::neg_transformer(THD *thd)
 Item *Item_func_isnull::neg_transformer(THD *thd)
 {
   Item *item= new Item_func_isnotnull(args[0]);
-  // see comment before fix_fields in Item_bool_rowready_func2::neg_transformer
-  if (item)
-    item->fix_fields(thd, 0, &item);
   return item;
 }
 
@@ -2765,9 +2741,6 @@ Item *Item_func_isnull::neg_transformer(THD *thd)
 Item *Item_func_isnotnull::neg_transformer(THD *thd)
 {
   Item *item= new Item_func_isnull(args[0]);
-  // see comment before fix_fields in Item_bool_rowready_func2::neg_transformer
-  if (item)
-    item->fix_fields(thd, 0, &item);
   return item;
 }
 
@@ -2777,9 +2750,6 @@ Item *Item_cond_and::neg_transformer(THD *thd)	/* NOT(a AND b AND ...)  -> */
 {
   neg_arguments(thd);
   Item *item= new Item_cond_or(list);
-  // see comment before fix_fields in Item_bool_rowready_func2::neg_transformer
-  if (item)
-    item->fix_fields(thd, 0, &item);
   return item;
 }
 
@@ -2789,9 +2759,6 @@ Item *Item_cond_or::neg_transformer(THD *thd)	/* NOT(a OR b OR ...)  -> */
 {
   neg_arguments(thd);
   Item *item= new Item_cond_and(list);
-  // see comment before fix_fields in Item_bool_rowready_func2::neg_transformer
-  if (item)
-    item->fix_fields(thd, 0, &item);
   return item;
 }
 

sql/item_cmpfunc.h

@@ -274,7 +274,7 @@ class Item_func_equal :public Item_bool_rowready_func2
   enum Functype rev_functype() const { return EQUAL_FUNC; }
   cond_result eq_cmp_result() const { return COND_TRUE; }
   const char *func_name() const { return "<=>"; }
-  Item* neg_transformer(THD *thd) { return 0; }
+  Item *neg_transformer(THD *thd) { return 0; }
 };
 
 

sql/sql_select.cc

@@ -4401,19 +4401,6 @@ optimize_cond(THD *thd, COND *conds, Item::cond_result *cond_value)
   if (conds)
   {
     DBUG_EXECUTE("where", print_where(conds, "original"););
-    /* Eliminate NOT operators; in case of PS/SP do it once */
-    if (thd->current_arena->is_first_stmt_execute())
-    {
-      Item_arena *arena= thd->current_arena, backup;
-      thd->set_n_backup_item_arena(arena, &backup);
-      conds= eliminate_not_funcs(thd, conds);
-      select->prep_where= conds->copy_andor_structure(thd);
-      thd->restore_backup_item_arena(arena, &backup);
-    }
-    else
-      conds= eliminate_not_funcs(thd, conds);
-    DBUG_EXECUTE("where", print_where(conds, "after negation elimination"););
-
     /* change field = field to field = const for each found field = const */
     propagate_cond_constants((I_List<COND_CMP> *) 0, conds, conds);
     /*

sql/sql_yacc.yy

@@ -2755,8 +2755,16 @@ simple_expr:
 	| '+' expr %prec NEG	{ $$= $2; }
 	| '-' expr %prec NEG    { $$= new Item_func_neg($2); }
 	| '~' expr %prec NEG	{ $$= new Item_func_bit_neg($2); }
-	| NOT expr %prec NEG	{ $$= new Item_func_not($2); }
-	| '!' expr %prec NEG	{ $$= new Item_func_not($2); }
+	| NOT expr %prec NEG
+          {
+            if (($$= $2->neg_transformer(YYTHD)) == 0)
+              $$= new Item_func_not($2);
+          }
+	| '!' expr %prec NEG
+          {
+            if (($$= $2->neg_transformer(YYTHD)) == 0)
+              $$= new Item_func_not($2);
+          }
 	| '(' expr ')'		{ $$= $2; }
 	| '(' expr ',' expr_list ')'
 	  {