This patch removes nblocksx, nblocksy arrays from pipe_texture (can be
recalculated if needed). Furthermore, pipe_format_block struct is gone
completely (again, contains just derived state).
nblocksx, nblocksy, block are also removed from pipe_transfer, together with
the format enum (can be obtained from the texture associated with the transfer).
The leading underscore is meaningful... This function is used by
_warning and _error functions as well as the more common
debug_printf().
debug_printf (without underscore) gets turned off when DEBUG is
disabled, but warning/error messages still use this function to get
their message out.
(cherry picked from commit 0ac879dca7)
The core reference counting code is centralized in p_refcnt.h.
This has some consequences related to struct pipe_buffer:
* The screen member of struct pipe_buffer must be initialized, or
pipe_buffer_reference() will crash trying to destroy a buffer with reference
count 0. u_simple_screen takes care of this, but I may have missed some of
the drivers not using it.
* Except for rare exceptions deep in winsys code, buffers must always be
allocated via pipe_buffer_create() or via screen->*buffer_create() rather
than via winsys->*buffer_create().
