btr_pcur_restore_position(): Add const qualifiers.
buf_LRU_block_remove_hashed_page(): Reduce the amount
of buf_page_hash_get() calls and add a UNIV_UNLIKELY hint
to an assertion-like test.
btr_cur_pessimistic_insert(): Remove local variable "block". Replace
an extraneous call to btr_cur_position() [with wrong "block", in r948]
with a debug assertion that the cursor is positioned on the preceding
record after the page split.
btr_pcur_restore_position(): Do not use btr_pcur_get_page(), because
the debug assertion there could fail. This bug was introduced in r928.
btr_cur_t: Move page_block to page_cur_t::block.
page_cur_get_block(), page_cur_get_page_zip(): New functions.
page_cur_position(): Add parameter block.
Remove many page_zip parameters, now that there is page_cur_get_page_zip().
Replace some page, page_zip parameters with block.
Add some const qualifiers to function parameters and remove casts.
PAGE_HEAP_NO_INFIMUM, PAGE_HEAP_NO_SUPREMUM, PAGE_HEAP_NO_USER_LOW:
New constants.
Replace some cursor code in low-level diagnostic functions with
direct management of rec, because buf_block_t::buf_fix_count may be 0
when the functions are called, and debug assertions would fail.
ibuf_reset_free_bits(): Remove, as there already is a similar function
ibuf_reset_free_bits_with_type().
ibuf_reset_free_bits_with_type(), ibuf_set_free_bits(),
ibuf_update_free_bits_if_full(), btr_leaf_page_release(),
buf_page_make_young(): Replace page_t with buf_block_t.
btr_compress(): Replace btr_page_get() with btr_block_get().
with page_get_page_no() and page_get_space_id(). We want to avoid
buf_block_align() calls, and the page_no and space_id are now stamped
on the pages early on.
Replace ut_ad(mtr_memo_contains(mtr, buf_block_align(ptr), ...))
with ut_ad(mtr_memo_contains_page(mtr, ptr, ...)) in order to reduce the
number of buf_block_align() calls.
