/*
* ChaCha/XChaCha NEON helper functions
*
* Copyright (C) 2016-2018 Linaro, Ltd. <ard.biesheuvel@linaro.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* Originally based on:
* ChaCha20 256-bit cipher algorithm, RFC7539, x64 SSSE3 functions
*
* Copyright (C) 2015 Martin Willi
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*/
#include <linux/linkage.h>
#include <asm/assembler.h>
#include <asm/cache.h>
.text
.align 6
/*
* chacha_permute - permute one block
*
* Permute one 64-byte block where the state matrix is stored in the four NEON
* registers v0-v3. It performs matrix operations on four words in parallel,
* but requires shuffling to rearrange the words after each round.
*
* The round count is given in w3.
*
* Clobbers: w3, x10, v4, v12
*/
SYM_FUNC_START_LOCAL(chacha_permute)
adr_l x10, ROT8
ld1 {v12.4s}, [x10]
.Ldoubleround:
// x0 += x1, x3 = rotl32(x3 ^ x0, 16)
add v0.4s, v0.4s, v1.4s
eor v3.16b, v3.16b, v0.16b
rev32 v3.8h, v3.8h
// x2 += x3, x1 = rotl32(x1 ^ x2, 12)
add v2.4s, v2.4s, v3.4s
eor v4.16b, v1.16b, v2.16b
shl v1.4s, v4.4s, #12
sri v1.4s, v4.4s, #20
// x0 += x1, x3 = rotl32(x3 ^ x0, 8)
add v0.4s, v0.4s, v1.4s
eor v3.16b, v3.16b, v0.16b
tbl v3.16b, {v3.16b}, v12.16b
// x2 += x3, x1 = rotl32(x1 ^ x2, 7)
add v2.4s, v2.4s, v3.4s
eor v4.16b, v1.16b, v2.16b
shl v1.4s, v4.4s, #7
sri v1.4s, v4.4s, #25
// x1 = shuffle32(x1, MASK(0, 3, 2, 1))
ext v1.16b, v1.16b, v1.16b, #4
// x2 = shuffle32(x2, MASK(1, 0, 3, 2))
ext v2.16b, v2.16b, v2.16b, #8
// x3 = shuffle32(x3, MASK(2, 1, 0, 3))
ext v3.16b, v3.16b, v3.16b, #12
// x0 += x1, x3 = rotl32(x3 ^ x0, 16)
add v0.4s, v0.4s, v1.4s
eor v3.16b, v3.16b, v0.16b
rev32 v3.8h, v3.8h
// x2 += x3, x1 = rotl32(x1 ^ x2, 12)
add v2.4s, v2.4s, v3.4s
eor v4.16b, v1.16b, v2.16b
shl v1.4s, v4.4s, #12
sri v1.4s, v4.4s, #20
// x0 += x1, x3 = rotl32(x3 ^ x0, 8)
add v0.4s, v0.4s, v1.4s
eor v3.16b, v3.16b, v0.16b
tbl v3.16b, {v3.16b}, v12.16b
// x2 += x3, x1 = rotl32(x1 ^ x2, 7)
add v2.4s, v2.4s, v3.4s
eor v4.16b, v1.16b, v2.16b
shl v1.4s, v4.4s, #7
sri v1.4s, v4.4s, #25
// x1 = shuffle32(x1, MASK(2, 1, 0, 3))
ext v1.16b, v1.16b, v1.16b, #12
// x2 = shuffle32(x2, MASK(1, 0, 3, 2))
ext v2.16b, v2.16b, v2.16b, #8
// x3 = shuffle32(x3, MASK(0, 3, 2, 1))
ext v3.16b, v3.16b, v3.16b, #4
subs w3, w3, #2
b.ne .Ldoubleround
ret
SYM_FUNC_END(chacha_permute)
SYM_FUNC_START(chacha_block_xor_neon)
// x0: Input state matrix, s
// x1: 1 data block output, o
// x2: 1 data block input, i
// w3: nrounds
stp x29, x30, [sp, #-16]!
mov x29, sp
// x0..3 = s0..3
ld1 {v0.4s-v3.4s}, [x0]
ld1 {v8.4s-v11.4s}, [x0]
bl chacha_permute
ld1 {v4.16b-v7.16b}, [x2]
// o0 = i0 ^ (x0 + s0)
add v0.4s, v0.4s, v8.4s
eor v0.16b, v0.16b, v4.16b
// o1 = i1 ^ (x1 + s1)
add v1.4s, v1.4s, v9.4s
eor v1.16b, v1.16b, v5.16b
// o2 = i2 ^ (x2 + s2)
add v2.4s, v2.4s, v10.4s
eor v2.16b, v2.16b, v6.16b
// o3 = i3 ^ (x3 + s3)
add v3.4s, v3.4s, v11.4s
eor v3.16b, v3.16b, v7.16b
st1 {v0.16b-v3.16b}, [x1]
ldp x29, x30, [sp], #16
ret
SYM_FUNC_END(chacha_block_xor_neon)
SYM_FUNC_START(hchacha_block_neon)
// x0: Input state matrix, s
// x1: output (8 32-bit words)
// w2: nrounds
stp x29, x30, [sp, #-16]!
mov x29, sp
ld1 {v0.4s-v3.4s}, [x0]
mov w3, w2
bl chacha_permute
st1 {v0.4s}, [x1], #16
st1 {v3.4s}, [x1]
ldp x29, x30, [sp], #16
ret
SYM_FUNC_END(hchacha_block_neon)
a0 .req w12
a1 .req w13
a2 .req w14
a3 .req w15
a4 .req w16
a5 .req w17
a6 .req w19
a7 .req w20
a8 .req w21
a9 .req w22
a10 .req w23
a11 .req w24
a12 .req w25
a13 .req w26
a14 .req w27
a15 .req w28
.align 6
SYM_FUNC_START(chacha_4block_xor_neon)
frame_push 10
// x0: Input state matrix, s
// x1: 4 data blocks output, o
// x2: 4 data blocks input, i
// w3: nrounds
// x4: byte count
adr_l x10, .Lpermute
and x5, x4, #63
add x10, x10, x5
//
// This function encrypts four consecutive ChaCha blocks by loading
// the state matrix in NEON registers four times. The algorithm performs
// each operation on the corresponding word of each state matrix, hence
// requires no word shuffling. For final XORing step we transpose the
// matrix by interleaving 32- and then 64-bit words, which allows us to
// do XOR in NEON registers.
//
// At the same time, a fifth block is encrypted in parallel using
// scalar registers
//
adr_l x9, CTRINC // ... and ROT8
ld1 {v30.4s-v31.4s}, [x9]
// x0..15[0-3] = s0..3[0..3]
add x8, x0, #16
ld4r { v0.4s- v3.4s}, [x0]
ld4r { v4.4s- v7.4s}, [x8], #16
ld4r { v8.4s-v11.4s}, [x8], #16
ld4r {v12.4s-v15.4s}, [x8]
mov a0, v0.s[0]
mov a1, v1.s[0]
mov a2, v2.s[0]
mov a3, v3.s[0]
mov a4, v4.s[0]
mov a5, v5.s[0]
mov a6, v6.s[0]
mov a7, v7.s[0]
mov a8, v8.s[0]
mov a9, v9.s[0]
mov a10, v10.s[0]
mov a11, v11.s[0]
mov a12, v12.s[0]
mov a13, v13.s[0]
mov a14, v14.s[0]
mov a15, v15.s[0]
// x12 += counter values 1-4
add v12.4s, v12.4s, v30.4s
.Ldoubleround4:
// x0 += x4, x12 = rotl32(x12 ^ x0, 16)
// x1 += x5, x13 = rotl32(x13 ^ x1, 16)
// x2 += x6, x14 = rotl32(x14 ^ x2, 16)
// x3 += x7, x15 = rotl32(x15 ^ x3, 16)
add v0.4s, v0.4s, v4.4s
add a0, a0, a4
add v1.4s, v1.4s, v5.4s
add a1, a1, a5
add v2.4s, v2.4s, v6.4s
add a2, a2, a6
add v3.4s, v3.4s, v7.4s
add a3, a3, a7
eor v12.16b, v12.16b, v0.16b
eor a12, a12, a0
eor v13.16b, v13.16b, v1.16b
eor a13, a13, a1
eor v14.16b, v14.16b, v2.16b
eor a14, a14, a2
eor v15.16b, v15.16b, v3.16b
eor a15, a15, a3
rev32 v12.8h, v12.8h
ror a12, a12, #16
rev32 v13.8h, v13.8h
ror a13, a13, #16
rev32 v14.8h, v14.8h
ror a14, a14, #16
rev32 v15.8h, v15.8h
ror a15, a15, #16
// x8 += x12, x4 = rotl32(x4 ^ x8, 12)
// x9 += x13, x5 = rotl32(x5 ^ x9, 12)
// x10 += x14, x6 = rotl32(x6 ^ x10, 12)
// x11 += x15, x7 = rotl32(x7 ^ x11, 12)
add v8.4s, v8.4s, v12.4s
add a8, a8, a12
add v9.4s, v9.4s, v13.4s
add a9, a9, a13
add v10.4s, v10.4s, v14.4s
add a10, a10, a14
add v11.4s, v11.4s, v15.4s
add a11, a11, a15
eor v16.16b, v4.16b, v8.16b
eor a4, a4, a8
eor v17.16b, v5.16b, v9.16b
eor a5, a5, a9
eor v18.16b, v6.16b, v10.16b
eor a6, a6, a10
eor v19.16b, v7.16b, v11.16b
eor a7, a7, a11
shl v4.4s, v16.4s, #12
shl v5.4s, v17.4s, #12
shl v6.4s, v18.4s, #12
shl v7.4s, v19.4s, #12
sri v4.4s, v16.4s, #20
ror a4, a4, #20
sri v5.4s, v17.4s, #20
ror a5, a5, #20
sri v6.4s, v18.4s, #20
ror a6, a6, #20
sri v7.4s, v19.4s, #20
ror a7, a7, #20
// x0 += x4, x12 = rotl32(x12 ^ x0, 8)
// x1 += x5, x13 = rotl32(x13 ^ x1, 8)
// x2 += x6, x14 = rotl32(x14 ^ x2, 8)
// x3 += x7, x15 = rotl32(x15 ^ x3, 8)
add v0.4s, v0.4s, v4.4s
add a0, a0, a4
add v1.4s, v1.4s, v5.4s
add a1, a1, a5
add v2.4s, v2.4s, v6.4s
add a2, a2, a6
add v3.4s, v3.4s, v7.4s
add a3, a3, a7
eor v12.16b, v12.16b, v0.16b
eor a12, a12, a0
eor v13.16b, v13.16b, v1.16b
eor a13, a13, a1
eor v14.16b, v14.16b, v2.16b
eor a14, a14, a2
eor v15.16b, v15.16b, v3.16b
eor a15, a15, a3
tbl v12.16b, {v12.16b}, v31.16b
ror a12, a12, #24
tbl v13.16b, {v13.16b}, v31.16b
ror a13, a13, #24
tbl v14.16b, {v14.16b}, v31.16b
ror a14, a14, #24
tbl v15.16b, {v15.16b}, v31.16b
ror a15, a15, #24
// x8 += x12, x4 = rotl32(x4 ^ x8, 7)
// x9 += x13, x5 = rotl32(x5 ^ x9, 7)
// x10 += x14, x6 = rotl32(x6 ^ x10, 7)
// x11 += x15, x7 = rotl32(x7 ^ x11, 7)
add v8.4s, v8.4s, v12.4s
add a8, a8, a12
add v9.4s, v9.4s, v13.4s
add a9, a9, a13
add v10.4s, v10.4s, v14.4s
add a10, a10, a14
add v11.4s, v11.4s, v15.4s
add a11, a11, a15
eor v16.16b, v4.16b, v8.16b
eor a4, a4, a8
eor v17.16b, v5.16b, v9.16b
eor a5, a5, a9
eor v18.16b, v6.16b, v10.16b
eor a6, a6, a10
eor v19.16b, v7.16b, v11.16b
eor a7, a7, a11
shl v4.4s, v16.4s, #7
shl v5.4s, v17.4s, #7
shl v6.4s, v18.4s, #7
shl v7.4s, v19.4s, #7
sri v4.4s, v16.4s, #25
ror a4, a4, #25
sri v5.4s, v17.4s, #25
ror a5, a5, #25
sri v6.4s, v18.4s, #25
ror a6, a6, #25
sri v7.4s, v19.4s, #25
ror a7, a7, #25
// x0 += x5, x15 = rotl32(x15 ^ x0, 16)
// x1 += x6, x12 = rotl32(x12 ^ x1, 16)
// x2 += x7, x13 = rotl32(x13 ^ x2, 16)
// x3 += x4, x14 = rotl32(x14 ^ x3, 16)
add v0.4s, v0.4s, v5.4s
add a0, a0, a5
add v1.4s, v1.4s, v6.4s
add a1, a1, a6
add v2.4s, v2.4s, v7.4s
add a2, a2, a7
add v3.4s, v3.4s, v4.4s
add a3, a3, a4
eor v15.16b, v15.16b, v0.16b
eor a15, a15, a0
eor v12.16b, v12.16b, v1.16b
eor a12, a12, a1
eor v13.16b, v13.16b, v2.16b
eor a13, a13, a2
eor v14.16b, v14.16b, v3.16b
eor a14, a14, a3
rev32 v15.8h, v15.8h
ror a15, a15, #16
rev32 v12.8h, v12.8h
ror a12, a12, #16
rev32 v13.8h, v13.8h
ror a13, a13, #16
rev32 v14.8h, v14.8h
ror a14, a14, #16
// x10 += x15, x5 = rotl32(x5 ^ x10, 12)
// x11 += x12, x6 = rotl32(x6 ^ x11, 12)
// x8 += x13, x7 = rotl32(x7 ^ x8, 12)
// x9 += x14, x4 = rotl32(x4 ^ x9, 12)
add v10.4s, v10.4s, v15.4s
add a10, a10, a15
add v11.4s, v11.4s, v12.4s
add a11, a11, a12
add v8.4s, v8.4s, v13.4s
add a8, a8, a13
add v9.4s, v9.4s, v14.4s
add a9, a9, a14
eor v16.16b, v5.16b, v10.16b
eor a5, a5, a10
eor v17.16b, v6.16b, v11.16b
eor a6, a6, a11
eor v18.16b, v7.16b, v8.16b
eor a7, a7, a8
eor v19.16b, v4.16b, v9.16b
eor a4, a4, a9
shl v5.4s, v16.4s, #12
shl v6.4s, v17.4s, #12
shl v7.4s, v18.4s, #12
shl v4.4s, v19.4s, #12
sri v5.4s, v16.4s, #20
ror a5, a5, #20
sri v6.4s, v17.4s, #20
ror a6, a6, #20
sri v7.4s, v18.4s, #20
ror a7, a7, #20
sri v4.4s, v19.4s, #20
ror a4, a4, #20
// x0 += x5, x15 = rotl32(x15 ^ x0, 8)
// x1 += x6, x12 = rotl32(x12 ^ x1, 8)
// x2 += x7, x13 = rotl32(x13 ^ x2, 8)
// x3 += x4, x14 = rotl32(x14 ^ x3, 8)
add v0.4s, v0.4s, v5.4s
add a0, a0, a5
add v1.4s, v1.4s, v6.4s
add a1, a1, a6
add v2.4s, v2.4s, v7.4s
add a2, a2, a7
add v3.4s, v3.4s, v4.4s
add a3, a3, a4
eor v15.16b, v15.16b, v0.16b
eor a15, a15, a0
eor v12.16b, v12.16b, v1.16b
eor a12, a12, a1
eor v13.16b, v13.16b, v2.16b
eor a13, a13, a2
eor v14.16b, v14.16b, v3.16b
eor a14, a14, a3
tbl v15.16b, {v15.16b}, v31.16b
ror a15, a15, #24
tbl v12.16b, {v12.16b}, v31.16b
ror a12, a12, #24
tbl v13.16b, {v13.16b}, v31.16b
ror a13, a13, #24
tbl v14.16b, {v14.16b}, v31.16b
ror a14, a14, #24
// x10 += x15, x5 = rotl32(x5 ^ x10, 7)
// x11 += x12, x6 = rotl32(x6 ^ x11, 7)
// x8 += x13, x7 = rotl32(x7 ^ x8, 7)
// x9 += x14, x4 = rotl32(x4 ^ x9, 7)
add v10.4s, v10.4s, v15.4s
add a10, a10, a15
add v11.4s, v11.4s, v12.4s
add a11, a11, a12
add v8.4s, v8.4s, v13.4s
add a8, a8, a13
add v9.4s, v9.4s, v14.4s
add a9, a9, a14
eor v16.16b, v5.16b, v10.16b
eor a5, a5, a10
eor v17.16b, v6.16b, v11.16b
eor a6, a6, a11
eor v18.16b, v7.16b, v8.16b
eor a7, a7, a8
eor v19.16b, v4.16b, v9.16b
eor a4, a4, a9
shl v5.4s, v16.4s, #7
shl v6.4s, v17.4s, #7
shl v7.4s, v18.4s, #7
shl v4.4s, v19.4s, #7
sri v5.4s, v16.4s, #25
ror a5, a5, #25
sri v6.4s, v17.4s, #25
ror a6, a6, #25
sri v7.4s, v18.4s, #25
ror a7, a7, #25
sri v4.4s, v19.4s, #25
ror a4, a4, #25
subs w3, w3, #2
b.ne .Ldoubleround4
ld4r {v16.4s-v19.4s}, [x0], #16
ld4r {v20.4s-v23.4s}, [x0], #16
// x12 += counter values 0-3
add v12.4s, v12.4s, v30.4s
// x0[0-3] += s0[0]
// x1[0-3] += s0[1]
// x2[0-3] += s0[2]
// x3[0-3] += s0[3]
add v0.4s, v0.4s, v16.4s
mov w6, v16.s[0]
mov w7, v17.s[0]
add v1.4s, v1.4s, v17.4s
mov w8, v18.s[0]
mov w9, v19.s[0]
add v2.4s, v2.4s, v18.4s
add a0, a0, w6
add a1, a1, w7
add v3.4s, v3.4s, v19.4s
add a2, a2, w8
add a3, a3, w9
CPU_BE( rev a0, a0 )
CPU_BE( rev a1, a1 )
CPU_BE( rev a2, a2 )
CPU_BE( rev a3, a3 )
ld4r {v24.4s-v27.4s}, [x0], #16
ld4r {v28.4s-v31.4s}, [x0]
// x4[0-3] += s1[0]
// x5[0-3] += s1[1]
// x6[0-3] += s1[2]
// x7[0-3] += s1[3]
add v4.4s, v4.4s, v20.4s
mov w6, v20.s[0]
mov w7, v21.s[0]
add v5.4s, v5.4s, v21.4s
mov w8, v22.s[0]
mov w9, v23.s[0]
add v6.4s, v6.4s, v22.4s
add a4, a4, w6
add a5, a5, w7
add v7.4s, v7.4s, v23.4s
add a6, a6, w8
add a7, a7, w9
CPU_BE( rev a4, a4 )
CPU_BE( rev a5, a5 )
CPU_BE( rev a6, a6 )
CPU_BE( rev a7, a7 )
// x8[0-3] += s2[0]
// x9[0-3] += s2[1]
// x10[0-3] += s2[2]
// x11[0-3] += s2[3]
add v8.4s, v8.4s, v24.4s
mov w6, v24.s[0]
mov w7, v25.s[0]
add v9.4s, v9.4s, v25.4s
mov w8, v26.s[0]
mov w9, v27.s[0]
add v10.4s, v10.4s, v26.4s
add a8, a8, w6
add a9, a9, w7
add v11.4s, v11.4s, v27.4s
add a10, a10, w8
add a11, a11, w9
CPU_BE( rev a8, a8 )
CPU_BE( rev a9, a9 )
CPU_BE( rev a10, a10 )
CPU_BE( rev a11, a11 )
// x12[0-3] += s3[0]
// x13[0-3] += s3[1]
// x14[0-3] += s3[2]
// x15[0-3] += s3[3]
add v12.4s, v12.4s, v28.4s
mov w6, v28.s[0]
mov w7, v29.s[0]
add v13.4s, v13.4s, v29.4s
mov w8, v30.s[0]
mov w9, v31.s[0]
add v14.4s, v14.4s, v30.4s
add a12, a12, w6
add a13, a13, w7
add v15.4s, v15.4s, v31.4s
add a14, a14, w8
add a15, a15, w9
CPU_BE( rev a12, a12 )
CPU_BE( rev a13, a13 )
CPU_BE( rev a14, a14 )
CPU_BE( rev a15, a15 )
// interleave 32-bit words in state n, n+1
ldp w6, w7, [x2], #64
zip1 v16.4s, v0.4s, v1.4s
ldp w8, w9, [x2, #-56]
eor a0, a0, w6
zip2 v17.4s, v0.4s, v1.4s
eor a1, a1, w7
zip1 v18.4s, v2.4s, v3.4s
eor a2, a2, w8
zip2 v19.4s, v2.4s, v3.4s
eor a3, a3, w9
ldp w6, w7, [x2, #-48]
zip1 v20.4s, v4.4s, v5.4s
ldp w8, w9, [x2, #-40]
eor a4, a4, w6
zip2 v21.4s, v4.4s, v5.4s
eor a5, a5, w7
zip1 v22.4s, v6.4s, v7.4s
eor a6, a6, w8
zip2 v23.4s, v6.4s, v7.4s
eor a7, a7, w9
ldp w6, w7, [x2, #-32]
zip1 v24.4s, v8.4s, v9.4s
ldp w8, w9, [x2, #-24]
eor a8, a8, w6
zip2 v25.4s, v8.4s, v9.4s
eor a9, a9, w7
zip1 v26.4s, v10.4s, v11.4s
eor a10, a10, w8
zip2 v27.4s, v10.4s, v11.4s
eor a11, a11, w9
ldp w6, w7, [x2, #-16]
zip1 v28.4s, v12.4s, v13.4s
ldp w8, w9, [x2, #-8]
eor a12, a12, w6
zip2 v29.4s, v12.4s, v13.4s
eor a13, a13, w7
zip1 v30.4s, v14.4s, v15.4s
eor a14, a14, w8
zip2 v31.4s, v14.4s, v15.4s
eor a15, a15, w9
add x3, x2, x4
sub x3, x3, #128 // start of last block
subs x5, x4, #128
csel x2, x2, x3, ge
// interleave 64-bit words in state n, n+2
zip1 v0.2d, v16.2d, v18.2d
zip2 v4.2d, v16.2d, v18.2d
stp a0, a1, [x1], #64
zip1 v8.2d, v17.2d, v19.2d
zip2 v12.2d, v17.2d, v19.2d
stp a2, a3, [x1, #-56]
subs x6, x4, #192
ld1 {v16.16b-v19.16b}, [x2], #64
csel x2, x2, x3, ge
zip1 v1.2d, v20.2d, v22.2d
zip2 v5.2d, v20.2d, v22.2d
stp a4, a5, [x1, #-48]
zip1 v9.2d, v21.2d, v23.2d
zip2 v13.2d, v21.2d, v23.2d
stp a6, a7, [x1, #-40]
subs x7, x4, #256
ld1 {v20.16b-v23.16b}, [x2], #64
csel x2, x2, x3, ge
zip1 v2.2d, v24.2d, v26.2d
zip2 v6.2d, v24.2d, v26.2d
stp a8, a9, [x1, #-32]
zip1 v10.2d, v25.2d, v27.2d
zip2 v14.2d, v25.2d, v27.2d
stp a10, a11, [x1, #-24]
subs x8, x4, #320
ld1 {v24.16b-v27.16b}, [x2], #64
csel x2, x2, x3, ge
zip1 v3.2d, v28.2d, v30.2d
zip2 v7.2d, v28.2d, v30.2d
stp a12, a13, [x1, #-16]
zip1 v11.2d, v29.2d, v31.2d
zip2 v15.2d, v29.2d, v31.2d
stp a14, a15, [x1, #-8]
tbnz x5, #63, .Lt128
ld1 {v28.16b-v31.16b}, [x2]
// xor with corresponding input, write to output
eor v16.16b, v16.16b, v0.16b
eor v17.16b, v17.16b, v1.16b
eor v18.16b, v18.16b, v2.16b
eor v19.16b, v19.16b, v3.16b
tbnz x6, #63, .Lt192
eor v20.16b, v20.16b, v4.16b
eor v21.16b, v21.16b, v5.16b
eor v22.16b, v22.16b, v6.16b
eor v23.16b, v23.16b, v7.16b
st1 {v16.16b-v19.16b}, [x1], #64
tbnz x7, #63, .Lt256
eor v24.16b, v24.16b, v8.16b
eor v25.16b, v25.16b, v9.16b
eor v26.16b, v26.16b, v10.16b
eor v27.16b, v27.16b, v11.16b
st1 {v20.16b-v23.16b}, [x1], #64
tbnz x8, #63, .Lt320
eor v28.16b, v28.16b, v12.16b
eor v29.16b, v29.16b, v13.16b
eor v30.16b, v30.16b, v14.16b
eor v31.16b, v31.16b, v15.16b
st1 {v24.16b-v27.16b}, [x1], #64
st1 {v28.16b-v31.16b}, [x1]
.Lout: frame_pop
ret
// fewer than 192 bytes of in/output
.Lt192: cbz x5, 1f // exactly 128 bytes?
ld1 {v28.16b-v31.16b}, [x10]
add x5, x5, x1
tbl v28.16b, {v4.16b-v7.16b}, v28.16b
tbl v29.16b, {v4.16b-v7.16b}, v29.16b
tbl v30.16b, {v4.16b-v7.16b}, v30.16b
tbl v31.16b, {v4.16b-v7.16b}, v31.16b
0: eor v20.16b, v20.16b, v28.16b
eor v21.16b, v21.16b, v29.16b
eor v22.16b, v22.16b, v30.16b
eor v23.16b, v23.16b, v31.16b
st1 {v20.16b-v23.16b}, [x5] // overlapping stores
1: st1 {v16.16b-v19.16b}, [x1]
b .Lout
// fewer than 128 bytes of in/output
.Lt128: ld1 {v28.16b-v31.16b}, [x10]
add x5, x5, x1
sub x1, x1, #64
tbl v28.16b, {v0.16b-v3.16b}, v28.16b
tbl v29.16b, {v0.16b-v3.16b}, v29.16b
tbl v30.16b, {v0.16b-v3.16b}, v30.16b
tbl v31.16b, {v0.16b-v3.16b}, v31.16b
ld1 {v16.16b-v19.16b}, [x1] // reload first output block
b 0b
// fewer than 256 bytes of in/output
.Lt256: cbz x6, 2f // exactly 192 bytes?
ld1 {v4.16b-v7.16b}, [x10]
add x6, x6, x1
tbl v0.16b, {v8.16b-v11.16b}, v4.16b
tbl v1.16b, {v8.16b-v11.16b}, v5.16b
tbl v2.16b, {v8.16b-v11.16b}, v6.16b
tbl v3.16b, {v8.16b-v11.16b}, v7.16b
eor v28.16b, v28.16b, v0.16b
eor v29.16b, v29.16b, v1.16b
eor v30.16b, v30.16b, v2.16b
eor v31.16b, v31.16b, v3.16b
st1 {v28.16b-v31.16b}, [x6] // overlapping stores
2: st1 {v20.16b-v23.16b}, [x1]
b .Lout
// fewer than 320 bytes of in/output
.Lt320: cbz x7, 3f // exactly 256 bytes?
ld1 {v4.16b-v7.16b}, [x10]
add x7, x7, x1
tbl v0.16b, {v12.16b-v15.16b}, v4.16b
tbl v1.16b, {v12.16b-v15.16b}, v5.16b
tbl v2.16b, {v12.16b-v15.16b}, v6.16b
tbl v3.16b, {v12.16b-v15.16b}, v7.16b
eor v28.16b, v28.16b, v0.16b
eor v29.16b, v29.16b, v1.16b
eor v30.16b, v30.16b, v2.16b
eor v31.16b, v31.16b, v3.16b
st1 {v28.16b-v31.16b}, [x7] // overlapping stores
3: st1 {v24.16b-v27.16b}, [x1]
b .Lout
SYM_FUNC_END(chacha_4block_xor_neon)
.section ".rodata", "a", %progbits
.align L1_CACHE_SHIFT
.Lpermute:
.set .Li, 0
.rept 128
.byte (.Li - 64)
.set .Li, .Li + 1
.endr
CTRINC: .word 1, 2, 3, 4
ROT8: .word 0x02010003, 0x06050407, 0x0a09080b, 0x0e0d0c0f