[Tarantool-patches] [PATCH v4 00/16] sql: refactor aggregate functions

[Mergen Imeev via Tarantool-patches <tarantool-patches@dev.tarantool.org>]

This patch-set refactor the aggregate functions and does some refactoring of the
SQL function infrastructure as a whole.

https://github.com/tarantool/tarantool/issues/4145
https://github.com/tarantool/tarantool/tree/imeevma/gh-4145-aggregate-functions

Changes in v2:
 - Added commit to remove possible UB in int-to-double implicit cast function.
 - Added commit to drop argv from struct sql_context.
 - Review fixes.

Changes in v3:
 - All functional changes were carried over from this patch-set. All that's left
   is refactoring.

Changes in v4:
 - Zeroblob optimization was removed, which allowed to simplify code and avoid
   some errors.

Mergen Imeev (16):
  sql: remove MEM_Zero flag from struct MEM
  sql: fix possible undefined behavior during cast
  sql: use register P1 for number of arguments
  sql: remove AggStep0 and OP_BuiltinFunction0
  sql: move collation to struct sql_context
  sql: introduce mem_append()
  sql: remove sql_vdbemem_finalize()
  sql: refactor SUM() function
  sql: refactor TOTAL() function
  sql: refactor AVG() function
  sql: refactor COUNT() function
  sql: refactor MIN() and MAX() functions
  sql: refactor GROUP_CONCAT() function
  sql: remove copying of result in finalizers
  sql: remove MEM_TYPE_AGG
  sql: remove field argv from struct sql_context

 src/box/sql/date.c    |  43 ---
 src/box/sql/expr.c    |  19 +-
 src/box/sql/func.c    | 812 +++++++++++++++++++-----------------------
 src/box/sql/main.c    |   5 +-
 src/box/sql/mem.c     | 200 ++---------
 src/box/sql/mem.h     |  51 +--
 src/box/sql/select.c  |  35 +-
 src/box/sql/sqlInt.h  |  40 +--
 src/box/sql/vdbe.c    | 202 ++---------
 src/box/sql/vdbeInt.h |   7 +-
 src/box/sql/vdbeapi.c | 108 ------
 src/box/sql/vdbeaux.c |  21 +-
 12 files changed, 504 insertions(+), 1039 deletions(-)

-- 
2.25.1