MDEV-20950 Reduce size of record offsetsbb-10.2-MDEV-20950-stack-offsets

offset_t: this is a type which represents one record offset.
It's unsigned short int.

a lot of functions: replace ulint with offset_t

btr_pcur_restore_position_func(),
page_validate(),
row_ins_scan_sec_index_for_duplicate(),
row_upd_clust_rec_by_insert_inherit_func(),
row_vers_impl_x_locked_low(),
trx_undo_prev_version_build():
  allocate record offsets on the stack instead of waiting for rec_get_offsets()
  to allocate it from mem_heap_t. So, reducing  memory allocations.

RECORD_OFFSET, INDEX_OFFSET:
  now it's less convenient to store pointers in offset_t*
  array. One pointer occupies now several offset_t. And those constant are start
  indexes into array to places where to store pointer values

REC_OFFS_HEADER_SIZE: adjusted for the new reality

REC_OFFS_NORMAL_SIZE:
  increase size from 100 to 300 which means less heap allocations.
  And sizeof(offset_t[REC_OFFS_NORMAL_SIZE]) now is 600 bytes which
  is smaller than previous 800 bytes.

REC_OFFS_SEC_INDEX_SIZE: adjusted for the new reality

rem0rec.h, rem0rec.ic, rem0rec.cc:
  various arguments, return values and local variables types were changed to
  fix numerous integer conversions issues.

enum field_type_t:
  offset types concept was introduces which replaces old offset flags stuff.
  Like in earlier version, 2 upper bits are used to store offset type.
  And this enum represents those types.

REC_OFFS_SQL_NULL, REC_OFFS_MASK: removed

get_type(), set_type(), get_value(), combine():
  these are convenience functions to work with offsets and it's types

rec_offs_base()[0]:
  still uses an old scheme with flags REC_OFFS_COMPACT and REC_OFFS_EXTERNAL

rec_offs_base()[i]:
  these have type offset_t now. Two upper bits contains type.

1 files changed, 8 insertions, 7 deletions

diff --git a/storage/innobase/include/page0cur.h b/storage/innobase/include/page0cur.h
index 18cc058ca6d..d91f1bd7ba7 100644
--- a/storage/innobase/include/page0cur.h
+++ b/storage/innobase/include/page0cur.h
@@ -29,6 +29,7 @@ Created 10/4/1994 Heikki Tuuri
 
 #include "buf0types.h"
 #include "page0page.h"
+#include "rem0types.h"
 #include "rem0rec.h"
 #include "data0data.h"
 #include "mtr0mtr.h"
@@ -151,7 +152,7 @@ page_cur_tuple_insert(
 	page_cur_t*	cursor,	/*!< in/out: a page cursor */
 	const dtuple_t*	tuple,	/*!< in: pointer to a data tuple */
 	dict_index_t*	index,	/*!< in: record descriptor */
-	ulint**		offsets,/*!< out: offsets on *rec */
+	offset_t**	offsets,/*!< out: offsets on *rec */
 	mem_heap_t**	heap,	/*!< in/out: pointer to memory heap, or NULL */
 	ulint		n_ext,	/*!< in: number of externally stored columns */
 	mtr_t*		mtr,	/*!< in: mini-transaction handle, or NULL */
@@ -178,7 +179,7 @@ page_cur_rec_insert(
 	page_cur_t*	cursor,	/*!< in/out: a page cursor */
 	const rec_t*	rec,	/*!< in: record to insert */
 	dict_index_t*	index,	/*!< in: record descriptor */
-	ulint*		offsets,/*!< in/out: rec_get_offsets(rec, index) */
+	offset_t*	offsets,/*!< in/out: rec_get_offsets(rec, index) */
 	mtr_t*		mtr);	/*!< in: mini-transaction handle, or NULL */
 /***********************************************************//**
 Inserts a record next to page cursor on an uncompressed page.
@@ -192,7 +193,7 @@ page_cur_insert_rec_low(
 				which the new record is inserted */
 	dict_index_t*	index,	/*!< in: record descriptor */
 	const rec_t*	rec,	/*!< in: pointer to a physical record */
-	ulint*		offsets,/*!< in/out: rec_get_offsets(rec, index) */
+	offset_t*	offsets,/*!< in/out: rec_get_offsets(rec, index) */
 	mtr_t*		mtr)	/*!< in: mini-transaction handle, or NULL */
 	MY_ATTRIBUTE((nonnull(1,2,3,4), warn_unused_result));
 
@@ -214,7 +215,7 @@ page_cur_insert_rec_zip(
 	page_cur_t*	cursor,	/*!< in/out: page cursor */
 	dict_index_t*	index,	/*!< in: record descriptor */
 	const rec_t*	rec,	/*!< in: pointer to a physical record */
-	ulint*		offsets,/*!< in/out: rec_get_offsets(rec, index) */
+	offset_t*	offsets,/*!< in/out: rec_get_offsets(rec, index) */
 	mtr_t*		mtr)	/*!< in: mini-transaction handle, or NULL */
 	MY_ATTRIBUTE((nonnull(1,2,3,4), warn_unused_result));
 /*************************************************************//**
@@ -240,7 +241,7 @@ page_cur_delete_rec(
 /*================*/
 	page_cur_t*		cursor,	/*!< in/out: a page cursor */
 	const dict_index_t*	index,	/*!< in: record descriptor */
-	const ulint*		offsets,/*!< in: rec_get_offsets(
+	const offset_t*		offsets,/*!< in: rec_get_offsets(
 					cursor->rec, index) */
 	mtr_t*			mtr);	/*!< in: mini-transaction handle */
 
@@ -388,14 +389,14 @@ page_delete_rec(
 	page_cur_t*		pcur,	/*!< in/out: page cursor on record
 					to delete */
 	page_zip_des_t*		page_zip,/*!< in: compressed page descriptor */
-	const ulint*		offsets);/*!< in: offsets for record */
+	const offset_t*		offsets);/*!< in: offsets for record */
 
 /** Index page cursor */
 
 struct page_cur_t{
 	const dict_index_t*	index;
 	rec_t*		rec;	/*!< pointer to a record on page */
-	ulint*		offsets;
+	offset_t*	offsets;
 	buf_block_t*	block;	/*!< pointer to the block containing rec */
 };