On Fri, 10 Feb 2017, Janne Grunau wrote:
>On 2017-01-15 22:55:48 +0200, Martin Storsjö wrote:
>>The theoretical maximum value of E is 193, so we can just
>>saturate the addition to 255.
>>
>>Before: Cortex A7 A8 A9 A53 A53/AArch64
>>vp9_loop_filter_v_4_8_neon: 143.0 127.7 114.8 88.0 87.7
>>vp9_loop_filter_v_8_8_neon: 241.0 197.2 173.7 140.0 136.7
>>vp9_loop_filter_v_16_8_neon: 497.0 419.5 379.7 293.0 275.7
>>vp9_loop_filter_v_16_16_neon: 965.2 818.7 731.4 579.0 452.0
>>After:
>>vp9_loop_filter_v_4_8_neon: 136.0 125.7 112.6 84.0 83.0
>>vp9_loop_filter_v_8_8_neon: 234.0 195.5 171.5 136.0 133.7
>>vp9_loop_filter_v_16_8_neon: 490.0 417.5 377.7 289.0 271.0
>>vp9_loop_filter_v_16_16_neon: 951.2 814.7 732.3 571.0 446.7
>>---
>> libavcodec/aarch64/vp9lpf_neon.S | 40
+++++++++-------------------------------
>> libavcodec/arm/vp9lpf_neon.S | 11 +++++------
>> 2 files changed, 14 insertions(+), 37 deletions(-)
>>
>>diff --git a/libavcodec/aarch64/vp9lpf_neon.S
b/libavcodec/aarch64/vp9lpf_neon.S
>>index 3b8e6eb..4553173 100644
>>--- a/libavcodec/aarch64/vp9lpf_neon.S
>>+++ b/libavcodec/aarch64/vp9lpf_neon.S
>>@@ -51,13 +51,6 @@
>> // see the arm version instead.
>>
>>
>>-.macro uabdl_sz dst1, dst2, in1, in2, sz
>>- uabdl \dst1, \in1\().8b, \in2\().8b
>>-.ifc \sz, .16b
>>- uabdl2 \dst2, \in1\().16b, \in2\().16b
>>-.endif
>>-.endm
>>-
>> .macro add_sz dst1, dst2, in1, in2, in3, in4, sz
>> add \dst1, \in1, \in3
>> .ifc \sz, .16b
>>@@ -86,20 +79,6 @@
>> .endif
>> .endm
>>
>>-.macro cmhs_sz dst1, dst2, in1, in2, in3, in4, sz
>>- cmhs \dst1, \in1, \in3
>>-.ifc \sz, .16b
>>- cmhs \dst2, \in2, \in4
>>-.endif
>>-.endm
>>-
>>-.macro xtn_sz dst, in1, in2, sz
>>- xtn \dst\().8b, \in1
>>-.ifc \sz, .16b
>>- xtn2 \dst\().16b, \in2
>>-.endif
>>-.endm
>>-
>> .macro usubl_sz dst1, dst2, in1, in2, sz
>> usubl \dst1, \in1\().8b, \in2\().8b
>> .ifc \sz, .16b
>>@@ -179,20 +158,20 @@
>> // tmpq2 == tmp3 + tmp4, etc.
>> .macro loop_filter wd, sz, mix, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7,
tmp8
>> .if \mix == 0
>>- dup v0.8h, w2 // E
>>- dup v1.8h, w2 // E
>>+ dup v0\sz, w2 // E
>> dup v2\sz, w3 // I
>> dup v3\sz, w4 // H
>> .else
>>- dup v0.8h, w2 // E
>>+ dup v0.8b, w2 // E
>> dup v2.8b, w3 // I
>> dup v3.8b, w4 // H
>>+ lsr w5, w2, #8
>> lsr w6, w3, #8
>> lsr w7, w4, #8
>>- ushr v1.8h, v0.8h, #8 // E
>>+ dup v1.8b, w5 // E
>> dup v4.8b, w6 // I
>>- bic v0.8h, #255, lsl 8 // E
>> dup v5.8b, w7 // H
>>+ trn1 v0.2d, v0.2d, v1.2d
>
>isn't this equivalent to
>
>dup v0.8h, w2
>uzp1 v0.16b, v0.16b, v0.16b
>
>on little endian?
Nice idea, but it isn't quite as straightforward on aarch64 - on arm it
would have been.
