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ffmpeg/libavcodec/aarch64/opus_imdct_neon.S

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aarch64: opus NEON iMDCT and FFT Opus celt decoding 11% faster and the iMDCT over 2.5 times faster on Apple's A7.
2014-04-28 15:56:43 +00:00
/*
* Copyright (c) 2014 Janne Grunau <janne-libav@jannau.net>
*
Merge commit 'd3f5b94762fb803c0f3b29f9ad6c5eaa813998ba' * commit 'd3f5b94762fb803c0f3b29f9ad6c5eaa813998ba': aarch64: opus NEON iMDCT and FFT Merged-by: Michael Niedermayer <michaelni@gmx.at>
2014-05-15 19:13:31 +00:00
* This file is part of FFmpeg.
aarch64: opus NEON iMDCT and FFT Opus celt decoding 11% faster and the iMDCT over 2.5 times faster on Apple's A7.
2014-04-28 15:56:43 +00:00
*
Merge commit 'd3f5b94762fb803c0f3b29f9ad6c5eaa813998ba' * commit 'd3f5b94762fb803c0f3b29f9ad6c5eaa813998ba': aarch64: opus NEON iMDCT and FFT Merged-by: Michael Niedermayer <michaelni@gmx.at>
2014-05-15 19:13:31 +00:00
* FFmpeg is free software; you can redistribute it and/or
aarch64: opus NEON iMDCT and FFT Opus celt decoding 11% faster and the iMDCT over 2.5 times faster on Apple's A7.
2014-04-28 15:56:43 +00:00
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
Merge commit 'd3f5b94762fb803c0f3b29f9ad6c5eaa813998ba' * commit 'd3f5b94762fb803c0f3b29f9ad6c5eaa813998ba': aarch64: opus NEON iMDCT and FFT Merged-by: Michael Niedermayer <michaelni@gmx.at>
2014-05-15 19:13:31 +00:00
* FFmpeg is distributed in the hope that it will be useful,
aarch64: opus NEON iMDCT and FFT Opus celt decoding 11% faster and the iMDCT over 2.5 times faster on Apple's A7.
2014-04-28 15:56:43 +00:00
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
Merge commit 'd3f5b94762fb803c0f3b29f9ad6c5eaa813998ba' * commit 'd3f5b94762fb803c0f3b29f9ad6c5eaa813998ba': aarch64: opus NEON iMDCT and FFT Merged-by: Michael Niedermayer <michaelni@gmx.at>
2014-05-15 19:13:31 +00:00
* License along with FFmpeg; if not, write to the Free Software
aarch64: opus NEON iMDCT and FFT Opus celt decoding 11% faster and the iMDCT over 2.5 times faster on Apple's A7.
2014-04-28 15:56:43 +00:00
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "libavutil/aarch64/asm.S"
#include "asm-offsets.h"
.macro shuffle a, b, c, d
const shuffle_\a\b\c\d align=4
.byte (\a * 4), (\a * 4 + 1), (\a * 4 + 2), (\a * 4 + 3)
.byte (\b * 4), (\b * 4 + 1), (\b * 4 + 2), (\b * 4 + 3)
.byte (\c * 4), (\c * 4 + 1), (\c * 4 + 2), (\c * 4 + 3)
.byte (\d * 4), (\d * 4 + 1), (\d * 4 + 2), (\d * 4 + 3)
endconst
.endm
shuffle 0, 2, 1, 3
shuffle 1, 0, 3, 2
shuffle 2, 3, 0, 1
shuffle 3, 1, 2, 0
function fft5_neon
lsl x2, x2, #3
ld1 {v24.2s}, [x1], x2
ld2 {v25.s,v26.s}[0], [x1], x2
ld2 {v25.s,v26.s}[1], [x1], x2
ld2 {v25.s,v26.s}[2], [x1], x2
ld2 {v25.s,v26.s}[3], [x1]
dup v6.4s, v24.s[0]
dup v7.4s, v24.s[1]
faddp v0.4s, v25.4s, v26.4s
// z[][0], z[][3]
fmul v16.4s, v25.4s, v15.s[0] // rr
fmul v17.4s, v25.4s, v15.s[1] // ri
fmul v18.4s, v26.4s, v15.s[0] // ir
fmul v19.4s, v26.4s, v15.s[1] // ii
faddp v0.4s, v0.4s, v0.4s
// z[][1], z[][2]
fmul v20.4s, v25.4s, v15.s[2] // rr
fmul v21.4s, v25.4s, v15.s[3] // ri
fmul v22.4s, v26.4s, v15.s[2] // ir
fmul v23.4s, v26.4s, v15.s[3] // ii
fadd v0.2s, v24.2s, v0.2s // out[0]
// z[0123][0], z[0123][3]
fsub v24.4s, v16.4s, v19.4s // (c).re = rr - ii;
fadd v27.4s, v16.4s, v19.4s // (d).re = rr + ii;
ld1 {v16.16b}, [x11]
ld1 {v19.16b}, [x14]
fadd v28.4s, v17.4s, v18.4s // (c).im = ri + ir;
fsub v31.4s, v18.4s, v17.4s // (d).im = -ri + ir;
ld1 {v17.16b}, [x12]
// z[0123][1], z[0123][2]
fsub v25.4s, v20.4s, v23.4s // (c).re = rr - ii;
fadd v26.4s, v20.4s, v23.4s // (d).re = rr + ii;
ld1 {v18.16b}, [x13]
fadd v29.4s, v21.4s, v22.4s // (c).im = ri + ir;
fsub v30.4s, v22.4s, v21.4s // (d).im = -ri + ir;
//real
tbl v20.16b, {v24.16b}, v16.16b
tbl v21.16b, {v25.16b}, v17.16b
tbl v22.16b, {v26.16b}, v18.16b
tbl v23.16b, {v27.16b}, v19.16b
//imag
tbl v16.16b, {v28.16b}, v16.16b
tbl v17.16b, {v29.16b}, v17.16b
tbl v18.16b, {v30.16b}, v18.16b
tbl v19.16b, {v31.16b}, v19.16b
fadd v6.4s, v6.4s, v20.4s
fadd v22.4s, v22.4s, v23.4s
fadd v7.4s, v7.4s, v16.4s
fadd v18.4s, v18.4s, v19.4s
fadd v21.4s, v21.4s, v22.4s
fadd v17.4s, v17.4s, v18.4s
fadd v6.4s, v6.4s, v21.4s
fadd v7.4s, v7.4s, v17.4s
ret
endfunc
function fft15_neon
mov x8, x1
mov x9, x30
add x2, x3, x3, lsl #1 // 3 * stride
add x1, x8, x3, lsl #3 // in + 1 * stride
bl fft5_neon
mov v1.8b, v0.8b
mov v2.16b, v6.16b
mov v3.16b, v7.16b
add x1, x8, x3, lsl #4 // in + 2 * stride
add x2, x3, x3, lsl #1 // 3 * stride
bl fft5_neon
zip1 v1.4s, v1.4s, v0.4s
mov v4.16b, v6.16b
mov v5.16b, v7.16b
mov x1, x8 // in + 0 * stride
add x2, x3, x3, lsl #1 // 3 * stride
bl fft5_neon
faddp v20.4s, v1.4s, v1.4s
ext v18.16b, v8.16b, v8.16b, #4
ext v19.16b, v9.16b, v9.16b, #4
mov v16.16b, v6.16b
mov v17.16b, v7.16b
fadd v20.2s, v20.2s, v0.2s
uzp1 v18.4s, v18.4s, v10.4s // exp[2,4,6,8].re
uzp1 v19.4s, v19.4s, v11.4s // exp[2,4,6,8].im
st1 {v20.2s}, [x0], #8 // out[0]
fmla v16.4s, v2.4s, v8.4s
fmls v16.4s, v3.4s, v9.4s
fmla v17.4s, v2.4s, v9.4s
fmla v17.4s, v3.4s, v8.4s
fmla v16.4s, v4.4s, v18.4s
fmls v16.4s, v5.4s, v19.4s
fmla v17.4s, v4.4s, v19.4s
fmla v17.4s, v5.4s, v18.4s
zip1 v18.4s, v16.4s, v17.4s
zip2 v19.4s, v16.4s, v17.4s
rev64 v31.4s, v14.4s
trn1 v28.2d, v1.2d, v1.2d
trn2 v29.2d, v1.2d, v1.2d
zip1 v30.2d, v14.2d, v31.2d
zip2 v31.2d, v14.2d, v31.2d
st1 {v18.4s,v19.4s}, [x0], #32 // out[1-4]
fmul v16.4s, v28.4s, v30.4s
fmul v17.4s, v29.4s, v30.4s
fmls v16.4s, v29.4s, v31.4s
fmla v17.4s, v28.4s, v31.4s
faddp v16.4s, v16.4s, v16.4s
faddp v17.4s, v17.4s, v17.4s
zip1 v18.2s, v16.2s, v17.2s
zip2 v19.2s, v16.2s, v17.2s
fadd v18.2s, v18.2s, v0.2s
fadd v0.2s, v19.2s, v0.2s
ext v30.16b, v12.16b, v12.16b, #4
ext v31.16b, v13.16b, v13.16b, #4
mov v16.16b, v6.16b
mov v17.16b, v7.16b
uzp1 v30.4s, v30.4s, v8.4s
uzp1 v31.4s, v31.4s, v9.4s
st1 {v18.2s}, [x0], #8 // out[5]
fmla v16.4s, v2.4s, v10.4s
fmls v16.4s, v3.4s, v11.4s
fmla v17.4s, v2.4s, v11.4s
fmla v17.4s, v3.4s, v10.4s
fmla v16.4s, v4.4s, v30.4s
fmls v16.4s, v5.4s, v31.4s
fmla v17.4s, v4.4s, v31.4s
fmla v17.4s, v5.4s, v30.4s
zip1 v18.4s, v16.4s, v17.4s
zip2 v19.4s, v16.4s, v17.4s
ext v30.16b, v10.16b, v10.16b, #4
ext v31.16b, v11.16b, v11.16b, #4
fmla v6.4s, v2.4s, v12.4s
fmls v6.4s, v3.4s, v13.4s
st1 {v18.4s,v19.4s}, [x0], #32 // out[6-9]
uzp1 v30.4s, v30.4s, v12.4s
uzp1 v31.4s, v31.4s, v13.4s
fmla v7.4s, v2.4s, v13.4s
fmla v7.4s, v3.4s, v12.4s
st1 {v0.2s}, [x0], #8 // out[10]
fmla v6.4s, v4.4s, v30.4s
fmls v6.4s, v5.4s, v31.4s
fmla v7.4s, v4.4s, v31.4s
fmla v7.4s, v5.4s, v30.4s
zip1 v18.4s, v6.4s, v7.4s
zip2 v19.4s, v6.4s, v7.4s
st1 {v18.4s,v19.4s}, [x0], #32 // out[11-14]
ret x9
endfunc
// x0: out, x1: out+len2, x2: exptab, x3: len2
function fft15_pass
ands x6, x3, #3
mov x4, x0
mov x5, x1
b.eq 9f
ld1 {v0.2s}, [x0], #8
ld1 {v1.2s}, [x1], #8
sub x3, x3, x6
subs x6, x6, #1
fadd v2.2s, v0.2s, v1.2s
fsub v3.2s, v0.2s, v1.2s
add x2, x2, #8
st1 {v2.2s}, [x4], #8
st1 {v3.2s}, [x5], #8
b.eq 9f
1:
subs x6, x6, #1
ldp s4, s5, [x2], #8
ldp s2, s3, [x1], #8
ldp s0, s1, [x0], #8
fmul s6, s2, s4
fmul s7, s2, s5
fmls s6, s3, v5.s[0]
fmla s7, s3, v4.s[0]
fsub s2, s0, s6
fsub s3, s1, s7
fadd s0, s0, s6
fadd s1, s1, s7
stp s2, s3, [x5], #8
stp s0, s1, [x4], #8
b.gt 1b
9:
ld1 {v4.4s,v5.4s}, [x2], #32
ld2 {v2.4s,v3.4s}, [x1], #32
uzp1 v6.4s, v4.4s, v5.4s
uzp2 v7.4s, v4.4s, v5.4s
ld2 {v0.4s,v1.4s}, [x0], #32
8:
subs x3, x3, #8
fmul v4.4s, v2.4s, v6.4s
fmul v5.4s, v2.4s, v7.4s
b.lt 4f
ld1 {v18.4s,v19.4s}, [x2], #32
fmls v4.4s, v3.4s, v7.4s
fmla v5.4s, v3.4s, v6.4s
ld2 {v22.4s,v23.4s}, [x1], #32
fsub v2.4s, v0.4s, v4.4s
fadd v0.4s, v0.4s, v4.4s
fsub v3.4s, v1.4s, v5.4s
fadd v1.4s, v1.4s, v5.4s
uzp1 v16.4s, v18.4s, v19.4s
uzp2 v17.4s, v18.4s, v19.4s
st2 {v2.4s,v3.4s}, [x5], #32
st2 {v0.4s,v1.4s}, [x4], #32
ld2 {v20.4s,v21.4s}, [x0], #32
fmul v18.4s, v22.4s, v16.4s
fmul v19.4s, v22.4s, v17.4s
b.eq 0f
ld1 {v4.4s,v5.4s}, [x2], #32
fmls v18.4s, v23.4s, v17.4s
fmla v19.4s, v23.4s, v16.4s
ld2 {v2.4s,v3.4s}, [x1], #32
fsub v22.4s, v20.4s, v18.4s
fadd v20.4s, v20.4s, v18.4s
fsub v23.4s, v21.4s, v19.4s
fadd v21.4s, v21.4s, v19.4s
uzp1 v6.4s, v4.4s, v5.4s
uzp2 v7.4s, v4.4s, v5.4s
st2 {v22.4s,v23.4s}, [x5], #32
st2 {v20.4s,v21.4s}, [x4], #32
ld2 {v0.4s,v1.4s}, [x0], #32
b 8b
4:
fmls v4.4s, v3.4s, v7.4s
fmla v5.4s, v3.4s, v6.4s
fsub v2.4s, v0.4s, v4.4s
fadd v0.4s, v0.4s, v4.4s
fsub v3.4s, v1.4s, v5.4s
fadd v1.4s, v1.4s, v5.4s
st2 {v2.4s,v3.4s}, [x5], #32
st2 {v0.4s,v1.4s}, [x4], #32
ret
0:
fmls v18.4s, v23.4s, v17.4s
fmla v19.4s, v23.4s, v16.4s
fsub v22.4s, v20.4s, v18.4s
fadd v20.4s, v20.4s, v18.4s
fsub v23.4s, v21.4s, v19.4s
fadd v21.4s, v21.4s, v19.4s
st2 {v22.4s,v23.4s}, [x5], #32
st2 {v20.4s,v21.4s}, [x4], #32
ret
endfunc
function fft30_neon align=6
sub sp, sp, #0x20
stp x20, x21, [sp]
stp x22, x30, [sp, #0x10]
mov x21, x1
mov x22, x2
mov x20, x4
mov x0, x21
mov x1, x22
lsl x3, x20, #1
bl fft15_neon
add x0, x21, #15*8
add x1, x22, x20, lsl #3
lsl x3, x20, #1
bl fft15_neon
ldr x2, [x10, #(CELT_EXPTAB + 8)] // s->exptab[1]
add x0, x21, #0
add x1, x21, #15*8
mov x3, #15
ldp x20, x21, [sp]
ldp x22, x30, [sp, #0x10]
add sp, sp, #0x20
b fft15_pass
endfunc
.macro def_fft n, n2
function fft\n\()_neon align=6
sub sp, sp, #0x30
stp x20, x21, [sp]
stp x22, x30, [sp, #0x10]
stp x23, x24, [sp, #0x20]
mov x21, x1
mov x22, x2
mov x23, x3
mov x20, x4
sub x3, x3, #1
lsl x4, x4, #1
bl fft\n2\()_neon
add x1, x21, #(\n2 * 8)
add x2, x22, x20, lsl #3
sub x3, x23, #1
lsl x4, x20, #1
bl fft\n2\()_neon
add x5, x10, #CELT_EXPTAB
mov x0, x21
ldr x2, [x5, x23, lsl #3] // s->exptab[N]
add x1, x21, #(\n2 * 8)
mov x3, #\n2
ldp x20, x21, [sp]
ldp x22, x30, [sp, #0x10]
ldp x23, x24, [sp, #0x20]
add sp, sp, #0x30
b fft15_pass
endfunc
.endm
def_fft 60, 30
def_fft 120, 60
def_fft 240, 120
def_fft 480, 240
def_fft 960, 480
function fft_b15_calc_neon
sub sp, sp, #0x50
ldr x8, [x0, #CELT_EXPTAB] // s->exptab[0]
movrel x6, fact5
movrel x11, shuffle_0213
movrel x12, shuffle_1032
movrel x13, shuffle_2301
movrel x14, shuffle_3120
add x8, x8, #8
movrel x5, fft_tab_neon
stp x20, x30, [sp]
stp d8, d9, [sp, #0x10]
stp d10, d11, [sp, #0x20]
stp d12, d13, [sp, #0x30]
stp d14, d15, [sp, #0x40]
ld1 {v15.4s}, [x6]
ld1 {v0.4s,v1.4s}, [x8], #32
ld1 {v6.2s}, [x8], #8
ld1 {v2.4s,v3.4s}, [x8], #32
ld1 {v7.2s}, [x8], #8
ld1 {v4.4s,v5.4s}, [x8], #32
uzp1 v8.4s, v0.4s, v1.4s // exp[ 1 - 4].re
uzp2 v9.4s, v0.4s, v1.4s // exp[ 1 - 4].im
uzp1 v10.4s, v2.4s, v3.4s // exp[ 6 - 9].re
uzp2 v11.4s, v2.4s, v3.4s // exp[ 6 - 9].im
uzp1 v12.4s, v4.4s, v5.4s // exp[11 - 14].re
uzp2 v13.4s, v4.4s, v5.4s // exp[11 - 14].im
zip1 v14.4s, v6.4s, v7.4s // exp[5,10].re/exp[5,10].im
add x5, x5, x3, lsl #3
ldr x5, [x5]
mov x10, x0
blr x5
ldp x20, x30, [sp]
ldp d8, d9, [sp, #0x10]
ldp d10, d11, [sp, #0x20]
ldp d12, d13, [sp, #0x30]
ldp d14, d15, [sp, #0x40]
add sp, sp, #0x50
ret
endfunc
const fft_tab_neon
.quad fft15_neon
.quad fft30_neon
.quad fft60_neon
.quad fft120_neon
.quad fft240_neon
.quad fft480_neon
.quad fft960_neon
endconst
function ff_celt_imdct_half_neon, export=1
sub sp, sp, #0x20
stp x21, x30, [sp]
str s0, [sp, #0x10]
ldp w5, w6, [x0, #CELT_LEN2] // CELT_LEN4
mov x10, x0
mov x21, x1
sub w5, w5, #1
lsl x7, x3, #3 // 2 * stride * sizeof(float)
sub x8, xzr, x3, lsl #3 // -2 * stride * sizeof(float)
mul x5, x5, x3
ldp x9, x10, [x0, #CELT_TMP] // CELT_TWIDDLE
ldr w3, [x0, #CELT_FFT_N]
add x5, x2, x5, lsl #2
mov x11, x9
sub w6, w6, #4
ld1 {v0.s}[0], [x5], x8
ld1 {v1.s}[0], [x2], x7
ld1 {v4.4s,v5.4s}, [x10], #32
ld1 {v0.s}[1], [x5], x8
ld1 {v1.s}[1], [x2], x7
uzp1 v2.4s, v4.4s, v5.4s
ld1 {v0.s}[2], [x5], x8
ld1 {v1.s}[2], [x2], x7
uzp2 v3.4s, v4.4s, v5.4s
ld1 {v0.s}[3], [x5], x8
ld1 {v1.s}[3], [x2], x7
1:
subs w6, w6, #4
ld1 {v20.s}[0], [x5], x8
ld1 {v21.s}[0], [x2], x7
ld1 {v4.4s,v5.4s}, [x10], #32
fmul v6.4s, v0.4s, v2.4s
fmul v7.4s, v0.4s, v3.4s
ld1 {v20.s}[1], [x5], x8
ld1 {v21.s}[1], [x2], x7
fmls v6.4s, v1.4s, v3.4s
fmla v7.4s, v1.4s, v2.4s
ld1 {v20.s}[2], [x5], x8
ld1 {v21.s}[2], [x2], x7
uzp1 v2.4s, v4.4s, v5.4s
uzp2 v3.4s, v4.4s, v5.4s
ld1 {v20.s}[3], [x5], x8
ld1 {v21.s}[3], [x2], x7
zip1 v4.4s, v6.4s, v7.4s
zip2 v5.4s, v6.4s, v7.4s
fmul v6.4s, v20.4s, v2.4s
fmul v7.4s, v20.4s, v3.4s
st1 {v4.4s,v5.4s}, [x9], #32
fmls v6.4s, v21.4s, v3.4s
fmla v7.4s, v21.4s, v2.4s
b.eq 3f
subs w6, w6, #4
ld1 {v4.4s,v5.4s}, [x10], #32
ld1 {v0.s}[0], [x5], x8
ld1 {v1.s}[0], [x2], x7
uzp1 v2.4s, v4.4s, v5.4s
ld1 {v0.s}[1], [x5], x8
ld1 {v1.s}[1], [x2], x7
uzp2 v3.4s, v4.4s, v5.4s
ld1 {v0.s}[2], [x5], x8
ld1 {v1.s}[2], [x2], x7
zip1 v4.4s, v6.4s, v7.4s
zip2 v5.4s, v6.4s, v7.4s
ld1 {v0.s}[3], [x5], x8
ld1 {v1.s}[3], [x2], x7
st1 {v4.4s,v5.4s}, [x9], #32
b.gt 1b
fmul v6.4s, v0.4s, v2.4s
fmul v7.4s, v0.4s, v3.4s
fmls v6.4s, v1.4s, v3.4s
fmla v7.4s, v1.4s, v2.4s
3:
zip1 v4.4s, v6.4s, v7.4s
zip2 v5.4s, v6.4s, v7.4s
st1 {v4.4s,v5.4s}, [x9], #32
mov x2, x11
mov x4, #1
bl fft_b15_calc_neon
ldr w5, [x10, #CELT_LEN4]
ldr x6, [x10, #CELT_TWIDDLE]
ldr s31, [sp, #0x10]
add x1, x21, x5, lsl #2
add x3, x6, x5, lsl #2
sub x0, x1, #16
sub x2, x3, #16
mov x8, #-16
mov x7, #16
mov x10, x0
mov x11, x1
sub w5, w5, #4
ld1 {v0.4s}, [x0], x8
ld1 {v1.4s}, [x1], x7
ld1 {v2.4s}, [x2], x8
ld1 {v3.4s}, [x3], x7
uzp1 v4.4s, v0.4s, v1.4s // z[-i-2, -i-1, +i, i+1].re
uzp2 v6.4s, v0.4s, v1.4s // z[-i-2, -i-1, +i, i+1].im
uzp1 v5.4s, v2.4s, v3.4s // twidlle_exptab[-i-2, -i-1, +i, i+1].re
uzp2 v7.4s, v2.4s, v3.4s // twidlle_exptab[-i-2, -i-1, +i, i+1].im
fmul v1.4s, v6.4s, v5.4s
fmul v0.4s, v6.4s, v7.4s
2:
subs w5, w5, #4
ld1 {v20.4s}, [x0], x8
fmla v1.4s, v4.4s, v7.4s
fmls v0.4s, v4.4s, v5.4s
ld1 {v21.4s}, [x1], x7
ext v1.16b, v1.16b, v1.16b, #8
fmul v0.4s, v0.4s, v31.s[0]
ld1 {v2.4s}, [x2], x8
rev64 v1.4s, v1.4s
fmul v1.4s, v1.4s, v31.s[0]
ld1 {v3.4s}, [x3], x7
zip1 v5.4s, v0.4s, v1.4s
zip2 v7.4s, v0.4s, v1.4s
uzp1 v4.4s, v20.4s, v21.4s // z[-i-2, -i-1, +i, i+1].re
uzp2 v6.4s, v20.4s, v21.4s // z[-i-2, -i-1, +i, i+1].im
st1 {v5.4s}, [x10], x8
st1 {v7.4s}, [x11], x7
uzp1 v5.4s, v2.4s, v3.4s // twidlle_exptab[-i-2, -i-1, +i, i+1].re
uzp2 v7.4s, v2.4s, v3.4s // twidlle_exptab[-i-2, -i-1, +i, i+1].im
fmul v1.4s, v6.4s, v5.4s
fmul v0.4s, v6.4s, v7.4s
b.gt 2b
fmla v1.4s, v4.4s, v7.4s
fmls v0.4s, v4.4s, v5.4s
ext v1.16b, v1.16b, v1.16b, #8
fmul v0.4s, v0.4s, v31.s[0]
rev64 v1.4s, v1.4s
fmul v1.4s, v1.4s, v31.s[0]
zip1 v5.4s, v0.4s, v1.4s
zip2 v7.4s, v0.4s, v1.4s
st1 {v5.4s}, [x10], x8
st1 {v7.4s}, [x11], x7
ldp x21, x30, [sp]
add sp, sp, #0x20
ret
endfunc
// [0] = exp(2 * i * pi / 5), [1] = exp(2 * i * pi * 2 / 5)
const fact5 align=4
.float 0.30901699437494745, 0.95105651629515353
.float -0.80901699437494734, 0.58778525229247325
endconst