This makes the code slightly clearer, but doesn't make any functional
difference.
Signed-off-by: Martin Storsjö <martin@martin.st>

Align the second/third operands as they usually are.

Due to the wildly varying sizes of the written out operands
in aarch64 assembly, the column alignment is usually not as clear
as in arm assembly.

This is cherrypicked from libav commit
7995ebfa.
Signed-off-by: Martin Storsjö <martin@martin.st>

In the half/quarter cases where we don't use the min_eob array, defer
loading the pointer until we know it will be needed.

This is cherrypicked from libav commit
3a0d5e20.
Signed-off-by: Martin Storsjö <martin@martin.st>

This reduces the number of lines and reduces the duplication.

Also simplify the eob check for the half case.

If we are in the half case, we know we at least will need to do the
first three slices, we only need to check eob for the fourth one,
so we can hardcode the value to check against instead of loading
from the min_eob array.

Since at most one slice can be skipped in the first pass, we can
unroll the loop for filling zeros completely, as it was done for
the quarter case before.

This allows skipping loading the min_eob pointer when using the
quarter/half cases.

This is cherrypicked from libav commit
98ee855a.
Signed-off-by: Martin Storsjö <martin@martin.st>

* commit '4ab49626':
  libvpx: Cast a pointer to const to squelch a warning

This commit is a noop, see 09b3bbe6Merged-by: James Almer <jamrial@gmail.com>

* commit '721d57e6':
  vp56: Separate VP5 and VP6 dsp initialization
Merged-by: James Almer <jamrial@gmail.com>

* commit '3fd22538':
  prores: Change type of stride parameters to ptrdiff_t
Merged-by: James Almer <jamrial@gmail.com>

* commit 'f81be06c':
  cavs: Change type of stride parameters to ptrdiff_t
Merged-by: James Almer <jamrial@gmail.com>

* commit '802727b5':
  vp8: Update some assembly comments left unchanged in bd66f073Merged-by: James Almer <jamrial@gmail.com>

* commit '87c6c786':
  vp8: Change type of stride parameters to ptrdiff_t
Merged-by: James Almer <jamrial@gmail.com>

* commit 'd9d26a36':
  vp56: Change type of stride parameters to ptrdiff_t
Merged-by: James Almer <jamrial@gmail.com>

* commit '6892df92':
  vp3: Change type of stride parameters to ptrdiff_t
Merged-by: Clément Bœsch <u@pkh.me>

* commit '963b3ab1':
  doc: Document FATE option HWACCEL
Merged-by: Clément Bœsch <u@pkh.me>

* commit 'd42809f9':
  av1: Add codec_id and basic demuxing support
Merged-by: Clément Bœsch <u@pkh.me>

* commit '24130234':
  rtpdec_mpeg4: validate fmtp fields

Merged with fixed log message.
Merged-by: Clément Bœsch <u@pkh.me>

* commit '46e3936f':
  configure: Set __MSVCRT_VERSION__to 0x0700 for MinGW
Merged-by: Clément Bœsch <u@pkh.me>

* commit '6755eb5b':
  mss12: validate display dimensions

This commit is a noop, see ee9151b6Merged-by: Clément Bœsch <u@pkh.me>

* commit '33f10546':
  vc1: check that slices have a positive height

This commit is a noop, see e985cfd1Merged-by: Clément Bœsch <u@pkh.me>

* commit '09b23786':
  pcx: use the bytestream2 API for reading from input

This commit is a noop, see 8cd1c0feMerged-by: Clément Bœsch <u@pkh.me>

* commit '221402c1':
  pcx: check that the packet is large enough before reading the header

See 8cd1c0feMerged-by: Clément Bœsch <u@pkh.me>

* commit '15ee419b':
  pcx: properly pad the scanline

This commit is a noop, see d24de459Merged-by: Clément Bœsch <u@pkh.me>

* commit '409d1cd2':
  cook: use the bytestream2 API for reading extradata
Merged-by: Clément Bœsch <u@pkh.me>

* commit 'bba9d8bd':
  qpeg: fix an off by 1 error in the MV check

See dd3bfe3cMerged-by: Clément Bœsch <u@pkh.me>

* commit '796dca02':
  alac: do not return success if nothing was decoded

See e11983bdMerged-by: Clément Bœsch <u@pkh.me>

* commit 'f5d46d33':
  vmnc: check that subrectangles fit into their containing rectangles

See 6ba02602

This merge keeps our condition against w-i and h-j instead of bw and bh.
One may be more correct than the other, but I'm keeping our behaviour
here for safety reasons.

The style and formatting is merged.
Merged-by: Clément Bœsch <u@pkh.me>

* commit '83b92a85':
  golomb: Drop disabled cruft
Merged-by: Clément Bœsch <u@pkh.me>

* commit '014852e9':
  simple_idct: arm: Drop disabled code variant
Merged-by: Clément Bœsch <u@pkh.me>

* commit 'e2b99935':
  simple_idct: x86: Drop disabled IDCT implementation
Merged-by: Clément Bœsch <u@pkh.me>

* commit '7effebde':
  dvbsubdec: Remove disabled, near-duplicate debug code
Merged-by: Clément Bœsch <u@pkh.me>

* commit '93fed46a':
  timefilter: test: Drop some disabled debug cruft
Merged-by: Clément Bœsch <u@pkh.me>

* commit '0e285c2f':
  mpegvideo: Kill some disabled code
Merged-by: Clément Bœsch <u@pkh.me>

* commit 'f2f145f3':
  msmpeg4: Drop disabled debug cruft
Merged-by: Clément Bœsch <u@pkh.me>

* commit 'be1db21b':
  mathops: Drop disabled alternative mid_pred() implementation
Merged-by: Clément Bœsch <u@pkh.me>

* commit 'be3363f6':
  nsv: Drop disabled cruft
Merged-by: Clément Bœsch <u@pkh.me>

* commit 'b53d8c3c':
  mjpegdec: Drop disabled code

The last chunk is replaced with a comment describing the structure.
Merged-by: Clément Bœsch <u@pkh.me>

* commit '34c22a9c':
  faan(i)dct: Kill some disabled code
Merged-by: Clément Bœsch <u@pkh.me>

* commit 'a4b1b5aa':
  wc3movie: Drop unused cruft
Merged-by: Clément Bœsch <u@pkh.me>

* commit '17cb56b3':
  ffv1: Remove broken disabled cruft
Merged-by: Clément Bœsch <u@pkh.me>

* commit 'b96f0ab3':
  h264: Kill broken disabled cruft
Merged-by: Clément Bœsch <u@pkh.me>

* commit '42c4c2d2':
  aac: Drop broken cruft
Merged-by: Clément Bœsch <u@pkh.me>