aarch64: vp9itxfm: Do separate functions for half/quarter idct16 and idct32
authorMartin Storsjö <martin@martin.st>
Tue, 22 Nov 2016 20:58:35 +0000 (22:58 +0200)
committerMartin Storsjö <martin@martin.st>
Sat, 11 Mar 2017 11:14:25 +0000 (13:14 +0200)
commit9532a7d4d060f2a2741225a76945daed52dbc478
treec79b4c2db06447907fb34ce7c7d031c13f03305a
parent824589556cb7c4bfafb8a0190e71a10c628f5339
aarch64: vp9itxfm: Do separate functions for half/quarter idct16 and idct32

This work is sponsored by, and copyright, Google.

This avoids loading and calculating coefficients that we know will
be zero, and avoids filling the temp buffer with zeros in places
where we know the second pass won't read.

This gives a pretty substantial speedup for the smaller subpartitions.

The code size increases from 14740 bytes to 24292 bytes.

The idct16/32_end macros are moved above the individual functions; the
instructions themselves are unchanged, but since new functions are added
at the same place where the code is moved from, the diff looks rather
messy.

Before:
vp9_inv_dct_dct_16x16_sub1_add_neon:     236.7
vp9_inv_dct_dct_16x16_sub2_add_neon:    1051.0
vp9_inv_dct_dct_16x16_sub4_add_neon:    1051.0
vp9_inv_dct_dct_16x16_sub8_add_neon:    1051.0
vp9_inv_dct_dct_16x16_sub12_add_neon:   1387.4
vp9_inv_dct_dct_16x16_sub16_add_neon:   1387.6
vp9_inv_dct_dct_32x32_sub1_add_neon:     554.1
vp9_inv_dct_dct_32x32_sub2_add_neon:    5198.5
vp9_inv_dct_dct_32x32_sub4_add_neon:    5198.6
vp9_inv_dct_dct_32x32_sub8_add_neon:    5196.3
vp9_inv_dct_dct_32x32_sub12_add_neon:   6183.4
vp9_inv_dct_dct_32x32_sub16_add_neon:   6174.3
vp9_inv_dct_dct_32x32_sub20_add_neon:   7151.4
vp9_inv_dct_dct_32x32_sub24_add_neon:   7145.3
vp9_inv_dct_dct_32x32_sub28_add_neon:   8119.3
vp9_inv_dct_dct_32x32_sub32_add_neon:   8118.7

After:
vp9_inv_dct_dct_16x16_sub1_add_neon:     236.7
vp9_inv_dct_dct_16x16_sub2_add_neon:     640.8
vp9_inv_dct_dct_16x16_sub4_add_neon:     639.0
vp9_inv_dct_dct_16x16_sub8_add_neon:     842.0
vp9_inv_dct_dct_16x16_sub12_add_neon:   1388.3
vp9_inv_dct_dct_16x16_sub16_add_neon:   1389.3
vp9_inv_dct_dct_32x32_sub1_add_neon:     554.1
vp9_inv_dct_dct_32x32_sub2_add_neon:    3685.5
vp9_inv_dct_dct_32x32_sub4_add_neon:    3685.1
vp9_inv_dct_dct_32x32_sub8_add_neon:    3684.4
vp9_inv_dct_dct_32x32_sub12_add_neon:   5312.2
vp9_inv_dct_dct_32x32_sub16_add_neon:   5315.4
vp9_inv_dct_dct_32x32_sub20_add_neon:   7154.9
vp9_inv_dct_dct_32x32_sub24_add_neon:   7154.5
vp9_inv_dct_dct_32x32_sub28_add_neon:   8126.6
vp9_inv_dct_dct_32x32_sub32_add_neon:   8127.2

This is cherrypicked from libav commit
a63da4511d0fee66695ff4afd264ba1dbf1e812d.

Signed-off-by: Martin Storsjö <martin@martin.st>
libavcodec/aarch64/vp9itxfm_neon.S