/*
 * Copyright (c) 2021 Arm Limited.
 *
 * SPDX-License-Identifier: MIT
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to
 * deal in the Software without restriction, including without limitation the
 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
 * sell copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#include <cstdint>

#if defined(__aarch64__)

namespace arm_conv {
namespace pooling {


void a64_u8_nhwc_max_generic_depthfirst_impl(
  const uint64_t,
  const uint64_t n_valid_cells,
  uint64_t n_channels,
  const uint8_t *const *const inptrs,
  uint8_t *outptr
)
{
  __asm__ __volatile__(
    "mov x28, #0x0\n"
    "mov x27, #0x10\n" // cntb _, ALL, #1
    "mov x26, #0x20\n" // cntb _, ALL, #2
    "mov x25, #0x30\n" // cntb _, ALL, #3
    "cmp %x[n_channels], #0x40\n"
    "blt 7f\n"
    "1:"  // 4-vectors of channels
    "movi v7.16b, #0x0\n"
    "mov x19, %x[inptrs]\n"
    "movi v6.16b, #0x0\n"
    "lsr x24, %x[n_valid_cells], #0x2\n"
    "movi v5.16b, #0x0\n"
    "movi v4.16b, #0x0\n"
    "cbz x24, 4f\n"
    "ldp x23, x22, [x19, #0x0]\n"
    "ldp x21, x20, [x19, #0x10]\n"
    "add x19, x19, #0x20\n"
    "subs x24, x24, #0x1\n"
    "ldr q3, [x23, x28]\n"
    "ldr q2, [x22, x28]\n"
    "ldr q1, [x21, x28]\n"
    "ldr q0, [x20, x28]\n"
    "ldr q31, [x23, x27]\n"
    "ldr q30, [x22, x27]\n"
    "ldr q29, [x21, x27]\n"
    "ldr q28, [x20, x27]\n"
    "ldr q27, [x23, x26]\n"
    "ldr q21, [x22, x26]\n"
    "ldr q26, [x21, x26]\n"
    "ldr q17, [x20, x26]\n"
    "ldr q25, [x23, x25]\n"
    "ldr q20, [x22, x25]\n"
    "ldr q24, [x21, x25]\n"
    "ldr q16, [x20, x25]\n"
    "beq 3f\n"
    "2:"  // 4-vectors of channels: 4 inputs loop
    "umax v23.16b, v3.16b, v2.16b\n"
    "ldp x23, x22, [x19, #0x0]\n"
    "subs x24, x24, #0x1\n"
    "umax v19.16b, v1.16b, v0.16b\n"
    "ldp x21, x20, [x19, #0x10]\n"
    "add x19, x19, #0x20\n"
    "umax v22.16b, v31.16b, v30.16b\n"
    "ldr q3, [x23, x28]\n"
    "umax v18.16b, v29.16b, v28.16b\n"
    "umax v21.16b, v27.16b, v21.16b\n"
    "ldr q2, [x22, x28]\n"
    "umax v17.16b, v26.16b, v17.16b\n"
    "ldr q1, [x21, x28]\n"
    "umax v20.16b, v25.16b, v20.16b\n"
    "ldr q0, [x20, x28]\n"
    "umax v16.16b, v24.16b, v16.16b\n"
    "ldr q31, [x23, x27]\n"
    "umax v19.16b, v23.16b, v19.16b\n"
    "ldr q30, [x22, x27]\n"
    "umax v18.16b, v22.16b, v18.16b\n"
    "ldr q29, [x21, x27]\n"
    "umax v17.16b, v21.16b, v17.16b\n"
    "ldr q28, [x20, x27]\n"
    "umax v16.16b, v20.16b, v16.16b\n"
    "ldr q27, [x23, x26]\n"
    "umax v7.16b, v7.16b, v19.16b\n"
    "ldr q21, [x22, x26]\n"
    "umax v6.16b, v6.16b, v18.16b\n"
    "ldr q26, [x21, x26]\n"
    "umax v5.16b, v5.16b, v17.16b\n"
    "ldr q17, [x20, x26]\n"
    "umax v4.16b, v4.16b, v16.16b\n"
    "ldr q25, [x23, x25]\n"
    "ldr q20, [x22, x25]\n"
    "ldr q24, [x21, x25]\n"
    "ldr q16, [x20, x25]\n"
    "bgt 2b\n"
    "3:"  // 4-vectors of channels: 4 inputs tail
    "umax v23.16b, v3.16b, v2.16b\n"
    "umax v19.16b, v1.16b, v0.16b\n"
    "umax v22.16b, v31.16b, v30.16b\n"
    "umax v18.16b, v29.16b, v28.16b\n"
    "umax v21.16b, v27.16b, v21.16b\n"
    "umax v17.16b, v26.16b, v17.16b\n"
    "umax v20.16b, v25.16b, v20.16b\n"
    "umax v16.16b, v24.16b, v16.16b\n"
    "umax v19.16b, v23.16b, v19.16b\n"
    "umax v18.16b, v22.16b, v18.16b\n"
    "umax v17.16b, v21.16b, v17.16b\n"
    "umax v16.16b, v20.16b, v16.16b\n"
    "umax v7.16b, v7.16b, v19.16b\n"
    "umax v6.16b, v6.16b, v18.16b\n"
    "umax v5.16b, v5.16b, v17.16b\n"
    "umax v4.16b, v4.16b, v16.16b\n"
    "4:"  // 4-vectors of channels: After loop
    "ands x20, %x[n_valid_cells], #0x3\n"
    "beq 6f\n"
    "5:"  // 4-vectors of channels: Single input loop
    "ldr x23, [x19], #0x8\n"
    "subs x20, x20, #0x1\n"
    "ldr q3, [x23, x28]\n"
    "umax v7.16b, v7.16b, v3.16b\n"
    "ldr q31, [x23, x27]\n"
    "ldr q27, [x23, x26]\n"
    "umax v6.16b, v6.16b, v31.16b\n"
    "ldr q25, [x23, x25]\n"
    "umax v5.16b, v5.16b, v27.16b\n"
    "umax v4.16b, v4.16b, v25.16b\n"
    "bgt 5b\n"
    "6:"  // 4-vectors of channels: Single input loop: End
    "str q7, [%x[outptr], x28]\n"
    "add x28, x28, #0x40\n"
    "str q6, [%x[outptr], x27]\n"
    "add x27, x27, #0x40\n"
    "str q5, [%x[outptr], x26]\n"
    "add x26, x26, #0x40\n"
    "str q4, [%x[outptr], x25]\n"
    "add x25, x25, #0x40\n"
    "sub %x[n_channels], %x[n_channels], #0x40\n"
    "cmp %x[n_channels], #0x40\n"
    "bge 1b\n"
    "cbz %x[n_channels], 43f\n"
    "7:"  // Single vector of channels
    "cmp %x[n_channels], #0x10\n"
    "blt 14f\n"
    "8:"  // Single vector of channels: Loop
    "movi v7.16b, #0x0\n"
    "mov x19, %x[inptrs]\n"
    "lsr x24, %x[n_valid_cells], #0x2\n"
    "cbz x24, 11f\n"
    "ldp x23, x22, [x19, #0x0]\n"
    "ldp x21, x20, [x19, #0x10]\n"
    "add x19, x19, #0x20\n"
    "subs x24, x24, #0x1\n"
    "ldr q3, [x23, x28]\n"
    "ldr q2, [x22, x28]\n"
    "ldr q1, [x21, x28]\n"
    "ldr q0, [x20, x28]\n"
    "beq 10f\n"
    "9:"  // Single vector of channels: Loop: 4 inputs loop
    "umax v23.16b, v3.16b, v2.16b\n"
    "ldp x23, x22, [x19, #0x0]\n"
    "subs x24, x24, #0x1\n"
    "umax v19.16b, v1.16b, v0.16b\n"
    "ldp x21, x20, [x19, #0x10]\n"
    "add x19, x19, #0x20\n"
    "umax v19.16b, v23.16b, v19.16b\n"
    "ldr q3, [x23, x28]\n"
    "ldr q2, [x22, x28]\n"
    "umax v7.16b, v7.16b, v19.16b\n"
    "ldr q1, [x21, x28]\n"
    "ldr q0, [x20, x28]\n"
    "bgt 9b\n"
    "10:"  // Single vector of channels: Loop: 4 inputs tail
    "umax v23.16b, v3.16b, v2.16b\n"
    "umax v19.16b, v1.16b, v0.16b\n"
    "umax v19.16b, v23.16b, v19.16b\n"
    "umax v7.16b, v7.16b, v19.16b\n"
    "11:"  // Single vector of channels: Loop: After loop
    "ands x20, %x[n_valid_cells], #0x3\n"
    "beq 13f\n"
    "12:"  // Single vector of channels: Loop: Single input loop
    "ldr x23, [x19], #0x8\n"
    "subs x20, x20, #0x1\n"
    "ldr q3, [x23, x28]\n"
    "umax v7.16b, v7.16b, v3.16b\n"
    "bgt 12b\n"
    "13:"  // Single vector of channels: Loop: Single input loop: End
    "str q7, [%x[outptr], x28]\n"
    "add x28, x28, #0x10\n"
    "sub %x[n_channels], %x[n_channels], #0x10\n"
    "cmp %x[n_channels], #0x10\n"
    "bge 8b\n"
    "cbz %x[n_channels], 43f\n"
    "14:"  // Oddments
    "movi v7.16b, #0x0\n"
    "add %x[outptr], %x[outptr], x28\n"
    "mov x19, %x[inptrs]\n"
    "lsr x24, %x[n_valid_cells], #0x2\n"
    "cbz x24, 24f\n"
    "15:"  // Oddments: 4 inputs loop
    "movi v3.16b, #0x0\n"
    "ldp x23, x22, [x19, #0x0]\n"
    "add x23, x23, x28\n"
    "movi v2.16b, #0x0\n"
    "ldp x21, x20, [x19, #0x10]\n"
    "movi v1.16b, #0x0\n"
    "add x19, x19, #0x20\n"
    "movi v0.16b, #0x0\n"
    "add x22, x22, x28\n"
    "add x21, x21, x28\n"
    "add x20, x20, x28\n"
    "tbz %x[n_channels], #3, 19f\n"
    "ldr d3, [x23], #0x8\n"
    "ldr d2, [x22], #0x8\n"
    "ldr d1, [x21], #0x8\n"
    "ldr d0, [x20], #0x8\n"
    "tbz %x[n_channels], #2, 17f\n"
    "ld1 { v3.s }[2], [x23], #0x4\n"
    "ld1 { v2.s }[2], [x22], #0x4\n"
    "ld1 { v1.s }[2], [x21], #0x4\n"
    "ld1 { v0.s }[2], [x20], #0x4\n"
    "tbz %x[n_channels], #1, 16f\n"
    "ld1 { v3.h }[6], [x23], #0x2\n"
    "ld1 { v2.h }[6], [x22], #0x2\n"
    "ld1 { v1.h }[6], [x21], #0x2\n"
    "ld1 { v0.h }[6], [x20], #0x2\n"
    "tbz %x[n_channels], #0, 23f\n"
    "ld1 { v3.b }[14], [x23], #0x1\n"
    "ld1 { v2.b }[14], [x22], #0x1\n"
    "ld1 { v1.b }[14], [x21], #0x1\n"
    "ld1 { v0.b }[14], [x20], #0x1\n"
    "b 23f\n"
    "16:"  // Oddments: 4 inputs loop: Load: Bit 3: Bit 2: Bit 1: Unset
    "tbz %x[n_channels], #0, 23f\n"
    "ld1 { v3.b }[12], [x23], #0x1\n"
    "ld1 { v2.b }[12], [x22], #0x1\n"
    "ld1 { v1.b }[12], [x21], #0x1\n"
    "ld1 { v0.b }[12], [x20], #0x1\n"
    "b 23f\n"
    "17:"  // Oddments: 4 inputs loop: Load: Bit 3: Bit 2: Unset
    "tbz %x[n_channels], #1, 18f\n"
    "ld1 { v3.h }[4], [x23], #0x2\n"
    "ld1 { v2.h }[4], [x22], #0x2\n"
    "ld1 { v1.h }[4], [x21], #0x2\n"
    "ld1 { v0.h }[4], [x20], #0x2\n"
    "tbz %x[n_channels], #0, 23f\n"
    "ld1 { v3.b }[10], [x23], #0x1\n"
    "ld1 { v2.b }[10], [x22], #0x1\n"
    "ld1 { v1.b }[10], [x21], #0x1\n"
    "ld1 { v0.b }[10], [x20], #0x1\n"
    "b 23f\n"
    "18:"  // Oddments: 4 inputs loop: Load: Bit 3: Bit 2: Unset: Bit 1: Unset
    "tbz %x[n_channels], #0, 23f\n"
    "ld1 { v3.b }[8], [x23], #0x1\n"
    "ld1 { v2.b }[8], [x22], #0x1\n"
    "ld1 { v1.b }[8], [x21], #0x1\n"
    "ld1 { v0.b }[8], [x20], #0x1\n"
    "b 23f\n"
    "19:"  // Oddments: 4 inputs loop: Load: Bit 3: Unset
    "tbz %x[n_channels], #2, 21f\n"
    "ldr s3, [x23], #0x4\n"
    "ldr s2, [x22], #0x4\n"
    "ldr s1, [x21], #0x4\n"
    "ldr s0, [x20], #0x4\n"
    "tbz %x[n_channels], #1, 20f\n"
    "ld1 { v3.h }[2], [x23], #0x2\n"
    "ld1 { v2.h }[2], [x22], #0x2\n"
    "ld1 { v1.h }[2], [x21], #0x2\n"
    "ld1 { v0.h }[2], [x20], #0x2\n"
    "tbz %x[n_channels], #0, 23f\n"
    "ld1 { v3.b }[6], [x23], #0x1\n"
    "ld1 { v2.b }[6], [x22], #0x1\n"
    "ld1 { v1.b }[6], [x21], #0x1\n"
    "ld1 { v0.b }[6], [x20], #0x1\n"
    "b 23f\n"
    "20:"  // Oddments: 4 inputs loop: Load: Bit 3: Unset: Bit 2: Bit 1: Unset
    "tbz %x[n_channels], #0, 23f\n"
    "ld1 { v3.b }[4], [x23], #0x1\n"
    "ld1 { v2.b }[4], [x22], #0x1\n"
    "ld1 { v1.b }[4], [x21], #0x1\n"
    "ld1 { v0.b }[4], [x20], #0x1\n"
    "b 23f\n"
    "21:"  // Oddments: 4 inputs loop: Load: Bit 3: Unset: Bit 2: Unset
    "tbz %x[n_channels], #1, 22f\n"
    "ldr h3, [x23], #0x2\n"
    "ldr h2, [x22], #0x2\n"
    "ldr h1, [x21], #0x2\n"
    "ldr h0, [x20], #0x2\n"
    "tbz %x[n_channels], #0, 23f\n"
    "ld1 { v3.b }[2], [x23], #0x1\n"
    "ld1 { v2.b }[2], [x22], #0x1\n"
    "ld1 { v1.b }[2], [x21], #0x1\n"
    "ld1 { v0.b }[2], [x20], #0x1\n"
    "b 23f\n"
    "22:"  // Oddments: 4 inputs loop: Load: Bit 3: Unset: Bit 2: Unset: Bit 1: Unset
    "tbz %x[n_channels], #0, 23f\n"
    "ldr b3, [x23], #0x1\n"
    "ldr b2, [x22], #0x1\n"
    "ldr b1, [x21], #0x1\n"
    "ldr b0, [x20], #0x1\n"
    "23:"  // Oddments: 4 inputs loop: Load: Bit 3: End
    "umax v23.16b, v3.16b, v2.16b\n"
    "subs x24, x24, #0x1\n"
    "umax v19.16b, v1.16b, v0.16b\n"
    "umax v19.16b, v23.16b, v19.16b\n"
    "umax v7.16b, v7.16b, v19.16b\n"
    "bgt 15b\n"
    "24:"  // Oddments: After loop
    "ands x20, %x[n_valid_cells], #0x3\n"
    "beq 34f\n"
    "25:"  // Oddments: Single input loop
    "movi v3.16b, #0x0\n"
    "ldr x23, [x19], #0x8\n"
    "add x23, x23, x28\n"
    "tbz %x[n_channels], #3, 29f\n"
    "ldr d3, [x23], #0x8\n"
    "tbz %x[n_channels], #2, 27f\n"
    "ld1 { v3.s }[2], [x23], #0x4\n"
    "tbz %x[n_channels], #1, 26f\n"
    "ld1 { v3.h }[6], [x23], #0x2\n"
    "tbz %x[n_channels], #0, 33f\n"
    "ld1 { v3.b }[14], [x23], #0x1\n"
    "b 33f\n"
    "26:"  // Oddments: Single input loop: Load: Bit 3: Bit 2: Bit 1: Unset
    "tbz %x[n_channels], #0, 33f\n"
    "ld1 { v3.b }[12], [x23], #0x1\n"
    "b 33f\n"
    "27:"  // Oddments: Single input loop: Load: Bit 3: Bit 2: Unset
    "tbz %x[n_channels], #1, 28f\n"
    "ld1 { v3.h }[4], [x23], #0x2\n"
    "tbz %x[n_channels], #0, 33f\n"
    "ld1 { v3.b }[10], [x23], #0x1\n"
    "b 33f\n"
    "28:"  // Oddments: Single input loop: Load: Bit 3: Bit 2: Unset: Bit 1: Unset
    "tbz %x[n_channels], #0, 33f\n"
    "ld1 { v3.b }[8], [x23], #0x1\n"
    "b 33f\n"
    "29:"  // Oddments: Single input loop: Load: Bit 3: Unset
    "tbz %x[n_channels], #2, 31f\n"
    "ldr s3, [x23], #0x4\n"
    "tbz %x[n_channels], #1, 30f\n"
    "ld1 { v3.h }[2], [x23], #0x2\n"
    "tbz %x[n_channels], #0, 33f\n"
    "ld1 { v3.b }[6], [x23], #0x1\n"
    "b 33f\n"
    "30:"  // Oddments: Single input loop: Load: Bit 3: Unset: Bit 2: Bit 1: Unset
    "tbz %x[n_channels], #0, 33f\n"
    "ld1 { v3.b }[4], [x23], #0x1\n"
    "b 33f\n"
    "31:"  // Oddments: Single input loop: Load: Bit 3: Unset: Bit 2: Unset
    "tbz %x[n_channels], #1, 32f\n"
    "ldr h3, [x23], #0x2\n"
    "tbz %x[n_channels], #0, 33f\n"
    "ld1 { v3.b }[2], [x23], #0x1\n"
    "b 33f\n"
    "32:"  // Oddments: Single input loop: Load: Bit 3: Unset: Bit 2: Unset: Bit 1: Unset
    "tbz %x[n_channels], #0, 33f\n"
    "ldr b3, [x23], #0x1\n"
    "33:"  // Oddments: Single input loop: Load: Bit 3: End
    "umax v7.16b, v7.16b, v3.16b\n"
    "subs x20, x20, #0x1\n"
    "bgt 25b\n"
    "34:"  // Oddments: Single input loop: End
    "tbz %x[n_channels], #3, 38f\n"
    "st1 { v7.d }[0], [%x[outptr]], #0x8\n"
    "tbz %x[n_channels], #2, 36f\n"
    "st1 { v7.s }[2], [%x[outptr]], #0x4\n"
    "tbz %x[n_channels], #1, 35f\n"
    "st1 { v7.h }[6], [%x[outptr]], #0x2\n"
    "tbz %x[n_channels], #0, 42f\n"
    "st1 { v7.b }[14], [%x[outptr]], #0x1\n"
    "b 42f\n"
    "35:"  // Oddments: Store: Bit 3: Bit 2: Bit 1: Unset
    "tbz %x[n_channels], #0, 42f\n"
    "st1 { v7.b }[12], [%x[outptr]], #0x1\n"
    "b 42f\n"
    "36:"  // Oddments: Store: Bit 3: Bit 2: Unset
    "tbz %x[n_channels], #1, 37f\n"
    "st1 { v7.h }[4], [%x[outptr]], #0x2\n"
    "tbz %x[n_channels], #0, 42f\n"
    "st1 { v7.b }[10], [%x[outptr]], #0x1\n"
    "b 42f\n"
    "37:"  // Oddments: Store: Bit 3: Bit 2: Unset: Bit 1: Unset
    "tbz %x[n_channels], #0, 42f\n"
    "st1 { v7.b }[8], [%x[outptr]], #0x1\n"
    "b 42f\n"
    "38:"  // Oddments: Store: Bit 3: Unset
    "tbz %x[n_channels], #2, 40f\n"
    "st1 { v7.s }[0], [%x[outptr]], #0x4\n"
    "tbz %x[n_channels], #1, 39f\n"
    "st1 { v7.h }[2], [%x[outptr]], #0x2\n"
    "tbz %x[n_channels], #0, 42f\n"
    "st1 { v7.b }[6], [%x[outptr]], #0x1\n"
    "b 42f\n"
    "39:"  // Oddments: Store: Bit 3: Unset: Bit 2: Bit 1: Unset
    "tbz %x[n_channels], #0, 42f\n"
    "st1 { v7.b }[4], [%x[outptr]], #0x1\n"
    "b 42f\n"
    "40:"  // Oddments: Store: Bit 3: Unset: Bit 2: Unset
    "tbz %x[n_channels], #1, 41f\n"
    "st1 { v7.h }[0], [%x[outptr]], #0x2\n"
    "tbz %x[n_channels], #0, 42f\n"
    "st1 { v7.b }[2], [%x[outptr]], #0x1\n"
    "b 42f\n"
    "41:"  // Oddments: Store: Bit 3: Unset: Bit 2: Unset: Bit 1: Unset
    "tbz %x[n_channels], #0, 42f\n"
    "st1 { v7.b }[0], [%x[outptr]], #0x1\n"
    "42:"  // Oddments: Store: Bit 3: End

    "43:"  // End

    : [n_channels] "+&r" (n_channels), [outptr] "+&r" (outptr)
    : [inptrs] "r" (inptrs), [n_valid_cells] "r" (n_valid_cells)
    : "cc", "memory", "v0", "v1", "v2", "v3", "v4", "v5", "v6", "v7", "v16", "v17", "v18", "v19", "v20", "v21", "v22", "v23", "v24", "v25", "v26", "v27", "v28", "v29", "v30", "v31", "x19", "x20", "x21", "x22", "x23", "x24", "x25", "x26", "x27", "x28"
  );
}

}  // namespace pooling
}  // namespace arm_conv

#endif  // defined(__aarch64__)