Quite often, the original weights are multiple of 512. By prescaling them
by 1/512 when they are computed (once per frame), no intermediate shifting
is needed, and no prescaling on each call either.
The x86 code already used that trick.
Signed-off-by: Ronald S. Bultje <rsbultje@gmail.com>
The were broken since August of 2010 without anyone noticing until
three weeks ago. Nobody cares about it anymore and hopefully Marvell
will support NEON like in the PXA978 from now on.
There is only one caller, which does not need the shifting. Other use cases
are situations where different roundings would be needed.
The x86 and neon versions are modified accordingly.
Signed-off-by: Ronald S. Bultje <rsbultje@gmail.com>
This prevents having to sign-extend on 64-bit systems with 32-bit ints,
such as x86-64. Also fixes crashes on systems where we don't do it and
arguments are not in registers, such as Win64 for all weight functions.
Overall almost 4% faster, idct_add down from 350 to 85 cycles, idct_dc_add
down from 83 to 30 cycles.
squash: rv34 idct rearrange partial register loads
The alignment directive must obviously precede the label.
This was never noticed in ARM mode since the location is
already aligned there.
Signed-off-by: Mans Rullgard <mans@mansr.com>
Due to apprent bugs in the GNU assembler and/or linker, relocations
can be incorrectly processed if the alignment of a Thumb instruction
is changed in the output file compared to the input object.
This fixes crashes in h264 decoding with Thumb enabled. No effect in
ARM mode since everything is 4-byte aligned there.
Signed-off-by: Mans Rullgard <mans@mansr.com>
Perform dequantization while decoding coefficients instead of performing it
on the entire coefficients buffer.
Since quantized coefficients are very sparse, this usually causes a small
speedup. Speedup of around 1% on Panda board compared to the removed here
neon code. Global speedup is probably around 3%.
Signed-off-by: Kostya Shishkov <kostya.shishkov@gmail.com>
This is a hand-tuned version of the code with impossible parts of
the FASTDIV function ommitted.
2-5% faster overall on Cortex-A8.
Signed-off-by: Mans Rullgard <mans@mansr.com>
This prevents build errors when compiler and assembler default
targets differ. Ideally each file would declare the highest
level it requires. This is however not easily possible as it
complicates assembling pre-armv6t2 code in Thumb-2 mode.
HAVE_NEON is used as indicator for ARMv7-A since no other
symbol exists for this and NEON is only available in this
variant.
Signed-off-by: Mans Rullgard <mans@mansr.com>
The inline asm added in bf5d46d uses the 'y' modifier which
is only supported from gcc 4.5. This check allows building
with older compilers.
Signed-off-by: Mans Rullgard <mans@mansr.com>
