Removing "DTCollation Arg_comparator::cmp_collation".

Using a CHARSET_INFO pointer instead.

Author: Alexander Barkov

sql/item_cmpfunc.cc

@@ -494,10 +494,13 @@ bool Item_func::setup_args_and_comparator(THD *thd, Arg_comparator *cmp)
  DBUG_ASSERT(arg_count >= 2); // Item_func_nullif has arg_count == 3
 
  if (args[0]->cmp_type() == STRING_RESULT &&
- args[1]->cmp_type() == STRING_RESULT &&
- agg_arg_charsets_for_comparison(cmp->cmp_collation, args, 2))
+ args[1]->cmp_type() == STRING_RESULT)
+ {
+ DTCollation tmp;
+ if (agg_arg_charsets_for_comparison(tmp, args, 2))
  return true;
-
+ cmp->m_compare_collation= tmp.collation;
+ }
  // Convert constants when compared to int/year field
  DBUG_ASSERT(functype() != LIKE_FUNC);
  convert_const_compared_to_int_field(thd);
@@ -528,7 +531,7 @@ int Arg_comparator::set_compare_func(Item_func_or_sum *item, Item_result type)
 
  switch (type) {
  case TIME_RESULT:
- cmp_collation.collation= &my_charset_numeric;
+ m_compare_collation= &my_charset_numeric;
  break;
  case ROW_RESULT:
  {
@@ -666,17 +669,19 @@ bool get_mysql_time_from_str(THD *thd, String *str, timestamp_type warn_type,
 */
 bool Arg_comparator::agg_arg_charsets_for_comparison()
 {
- if (cmp_collation.set((*a)->collation, (*b)->collation, MY_COLL_CMP_CONV) ||
- cmp_collation.derivation == DERIVATION_NONE)
+ DTCollation tmp;
+ if (tmp.set((*a)->collation, (*b)->collation, MY_COLL_CMP_CONV) ||
+ tmp.derivation == DERIVATION_NONE)
  {
  my_coll_agg_error((*a)->collation, (*b)->collation, owner->func_name());
  return true;
  }
- if (agg_item_set_converter(cmp_collation, owner->func_name(),
+ if (agg_item_set_converter(tmp, owner->func_name(),
  a, 1, MY_COLL_CMP_CONV, 1) ||
- agg_item_set_converter(cmp_collation, owner->func_name(),
+ agg_item_set_converter(tmp, owner->func_name(),
  b, 1, MY_COLL_CMP_CONV, 1))
  return true;
+ m_compare_collation= tmp.collation;
  return false;
 }
 
@@ -909,7 +914,7 @@ int Arg_comparator::compare_string()
  {
  if (set_null)
  owner->null_value= 0;
- return sortcmp(res1,res2,cmp_collation.collation);
+ return sortcmp(res1, res2, compare_collation());
  }
  }
  if (set_null)
@@ -930,7 +935,7 @@ int Arg_comparator::compare_e_string()
  res2= (*b)->val_str(&value2);
  if (!res1 || !res2)
  return MY_TEST(res1 == res2);
- return MY_TEST(sortcmp(res1, res2, cmp_collation.collation) == 0);
+ return MY_TEST(sortcmp(res1, res2, compare_collation()) == 0);
 }
 
 

sql/item_cmpfunc.h

@@ -48,6 +48,7 @@ class Arg_comparator: public Sql_alloc
 {
  Item **a, **b;
  Item_result m_compare_type;
+ CHARSET_INFO *m_compare_collation;
  arg_cmp_func func;
  Item_func_or_sum *owner;
  bool set_null; // TRUE <=> set owner->null_value
@@ -65,16 +66,18 @@ class Arg_comparator: public Sql_alloc
  int compare_e_temporal(enum_field_types type);
 
 public:
- DTCollation cmp_collation;
  /* Allow owner function to use string buffers. */
  String value1, value2;
 
  Arg_comparator(): m_compare_type(STRING_RESULT),
+ m_compare_collation(&my_charset_bin),
  set_null(TRUE), comparators(0), thd(0),
  a_cache(0), b_cache(0) {};
  Arg_comparator(Item **a1, Item **a2): a(a1), b(a2),
- m_compare_type(STRING_RESULT), set_null(TRUE),
- comparators(0), thd(0), a_cache(0), b_cache(0) {};
+ m_compare_type(STRING_RESULT),
+ m_compare_collation(&my_charset_bin),
+ set_null(TRUE), comparators(0), thd(0),
+ a_cache(0), b_cache(0) {};
 
 public:
  inline int set_cmp_func(Item_func_or_sum *owner_arg,
@@ -115,6 +118,7 @@ class Arg_comparator: public Sql_alloc
  ((Item_func*)owner)->functype() == Item_func::EQUAL_FUNC);
  }
  Item_result compare_type() const { return m_compare_type; }
+ CHARSET_INFO *compare_collation() const { return m_compare_collation; }
  Arg_comparator *subcomparators() const { return comparators; }
  void cleanup()
  {
@@ -401,8 +405,7 @@ class Item_bool_rowready_func2 :public Item_bool_func2
  {
  return cmp.set_cmp_func(this, tmp_arg, tmp_arg + 1, true);
  }
- CHARSET_INFO *compare_collation() const
- { return cmp.cmp_collation.collation; }
+ CHARSET_INFO *compare_collation() const { return cmp.compare_collation(); }
  Item_result compare_type() const { return cmp.compare_type(); }
  Arg_comparator *get_comparator() { return &cmp; }
  void cleanup()
@@ -931,7 +934,7 @@ class Item_func_nullif :public Item_func_hybrid_field_type
  bool is_null();
  Item* propagate_equal_fields(THD *thd, const Context &ctx, COND_EQUAL *cond)
  {
- Context cmpctx(ANY_SUBST, cmp.compare_type(), cmp.cmp_collation.collation);
+ Context cmpctx(ANY_SUBST, cmp.compare_type(), cmp.compare_collation());
  args[0]->propagate_equal_fields_and_change_item_tree(thd, cmpctx,
  cond, &args[0]);
  args[1]->propagate_equal_fields_and_change_item_tree(thd, cmpctx,

sql/sql_select.cc

@@ -12766,7 +12766,7 @@ static bool check_row_equality(THD *thd, const Arg_comparator *comparators,
  is_converted= check_simple_equality(thd,
  Item::Context(Item::ANY_SUBST,
  tmp->compare_type(),
- tmp->cmp_collation.collation),
+  tmp->compare_collation()),
  left_item, right_item,
  cond_equal);
  }