Restore alphabetical order in lists, break overly long lines, do some
prettyprinting, add some explanatory section comments, group parts
together that belong together logically.
Previously, ff_h264_idct_add_neon (originally in the arm version) used
a non-regular transpose in order to be able to use more instructions
that deal with registers as 128 bit register pairs. The aarch64
translation doesn't do it to the same extent, but brought along the
same structure since it was a straight translation.
This reshuffles ff_h264_idct_add_neon, bringing it closer to
the C implementation, making the transpose_4x4H macro do a regular
transpose, usable for other algorithms as well.
Previously, the third and fourth output from transpose_4x4H were
swapped, and prior to cc29d96d5a, the same inputs as well. In
addition to just swapping the outputs, also renumber the intermediate
registers for better readability (making the register order match
transpose_4x8B).
This runs with the same number of cycles as before.
Signed-off-by: Martin Storsjö <martin@martin.st>
~25% faster dts decoding overall. The checkasm CPU cycles numbers are
not that useful since synth_filter_float() calls FFTContext.imdct_half().
cortex-a57 cortex-a53
synth_filter_float_c: 1866.2 3490.9
synth_filter_float_neon: 915.0 1531.5
With fftc.imdct_half forced to imdct_half_neon:
cortex-a57 cortex-a53
synth_filter_float_c: 1718.4 3025.3
synth_filter_float_neon: 926.2 1530.1
This allows running the code on android, where 64 bit binaries with
text relocations aren't allowed to be loaded.
Signed-off-by: Martin Storsjö <martin@martin.st>
llvm's integrated assembler does not accept spaces as macro argument
delimiter when targeting darwin. Using a explicit delimiter is a good
idea in principle since it makes case like 'macro 4 -2' vs 'macro 4 - 2'
clear.
Based on the x86 branchless get_cabac asm. get_cabac_noinline() gets
approximately 20% faster (no cycle counts available) compared to clang
from Xcode 5.1 beta5. More than 6% faster overall. A part of the overall
speedup might be explained by additional inlining of get_cabac().
