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/*
 * Copyright (c) 2009 Mans Rullgard <mans@mansr.com>
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * 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.
 *
 * FFmpeg is distributed in the hope that it will be useful,
 * 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
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include "asm.S"

        preserve8

        .text

.macro  call_2x_pixels  type, subp
function ff_\type\()_pixels16\subp\()_armv6, export=1
        push            {r0-r3, lr}
        bl              ff_\type\()_pixels8\subp\()_armv6
        pop             {r0-r3, lr}
        add             r0,  r0,  #8
        add             r1,  r1,  #8
        b               ff_\type\()_pixels8\subp\()_armv6
endfunc
.endm

call_2x_pixels          avg
call_2x_pixels          put, _x2
call_2x_pixels          put, _y2
call_2x_pixels          put, _x2_no_rnd
call_2x_pixels          put, _y2_no_rnd

function ff_put_pixels16_armv6, export=1
        push            {r4-r11}
1:
        ldr             r5,  [r1, #4]
        ldr             r6,  [r1, #8]
        ldr             r7,  [r1, #12]
        ldr             r4,  [r1], r2
        strd            r6,  r7,  [r0, #8]
        ldr             r9,  [r1, #4]
        strd            r4,  r5,  [r0],  r2
        ldr             r10, [r1, #8]
        ldr             r11, [r1, #12]
        ldr             r8,  [r1], r2
        strd            r10, r11, [r0, #8]
        subs            r3,  r3,  #2
        strd            r8,  r9,  [r0],  r2
        bne             1b

        pop             {r4-r11}
        bx              lr
endfunc

function ff_put_pixels8_armv6, export=1
        push            {r4-r7}
1:
        ldr             r5,  [r1, #4]
        ldr             r4,  [r1], r2
        ldr             r7,  [r1, #4]
        strd            r4,  r5,  [r0],  r2
        ldr             r6,  [r1], r2
        subs            r3,  r3,  #2
        strd            r6,  r7,  [r0],  r2
        bne             1b

        pop             {r4-r7}
        bx              lr
endfunc

function ff_put_pixels8_x2_armv6, export=1
        push            {r4-r11, lr}
        mov             r12, #1
        orr             r12, r12, r12, lsl #8
        orr             r12, r12, r12, lsl #16
1:
        ldr             r4,  [r1]
        subs            r3,  r3,  #2
        ldr             r5,  [r1, #4]
        ldr             r7,  [r1, #5]
        lsr             r6,  r4,  #8
        ldr             r8,  [r1, r2]!
        orr             r6,  r6,  r5,  lsl #24
        ldr             r9,  [r1, #4]
        ldr             r11, [r1, #5]
        lsr             r10, r8,  #8
        add             r1,  r1,  r2
        orr             r10, r10, r9,  lsl #24
        eor             r14, r4,  r6
        uhadd8          r4,  r4,  r6
        eor             r6,  r5,  r7
        uhadd8          r5,  r5,  r7
        and             r14, r14, r12
        and             r6,  r6,  r12
        uadd8           r4,  r4,  r14
        eor             r14, r8,  r10
        uadd8           r5,  r5,  r6
        eor             r6,  r9,  r11
        uhadd8          r8,  r8,  r10
        and             r14, r14, r12
        uhadd8          r9,  r9,  r11
        and             r6,  r6,  r12
        uadd8           r8,  r8,  r14
        strd            r4,  r5,  [r0],  r2
        uadd8           r9,  r9,  r6
        strd            r8,  r9,  [r0],  r2
        bne             1b

        pop             {r4-r11, pc}
endfunc

function ff_put_pixels8_y2_armv6, export=1
        push            {r4-r11}
        mov             r12, #1
        orr             r12, r12, r12, lsl #8
        orr             r12, r12, r12, lsl #16
        ldr             r4,  [r1]
        ldr             r5,  [r1, #4]
        ldr             r6,  [r1, r2]!
        ldr             r7,  [r1, #4]
1:
        subs            r3,  r3,  #2
        uhadd8          r8,  r4,  r6
        eor             r10, r4,  r6
        uhadd8          r9,  r5,  r7
        eor             r11, r5,  r7
        and             r10, r10, r12
        ldr             r4,  [r1, r2]!
        uadd8           r8,  r8,  r10
        and             r11, r11, r12
        uadd8           r9,  r9,  r11
        ldr             r5,  [r1, #4]
        uhadd8          r10, r4,  r6
        eor             r6,  r4,  r6
        uhadd8          r11, r5,  r7
        and             r6,  r6,  r12
        eor             r7,  r5,  r7
        uadd8           r10, r10, r6
        and             r7,  r7,  r12
        ldr             r6,  [r1, r2]!
        uadd8           r11, r11, r7
        strd            r8,  r9,  [r0],  r2
        ldr             r7,  [r1, #4]
        strd            r10, r11, [r0],  r2
        bne             1b

        pop             {r4-r11}
        bx              lr
endfunc

function ff_put_pixels8_x2_no_rnd_armv6, export=1
        push            {r4-r9, lr}
1:
        subs            r3,  r3,  #2
        ldr             r4,  [r1]
        ldr             r5,  [r1, #4]
        ldr             r7,  [r1, #5]
        ldr             r8,  [r1, r2]!
        ldr             r9,  [r1, #4]
        ldr             r14, [r1, #5]
        add             r1,  r1,  r2
        lsr             r6,  r4,  #8
        orr             r6,  r6,  r5,  lsl #24
        lsr             r12, r8,  #8
        orr             r12, r12, r9,  lsl #24
        uhadd8          r4,  r4,  r6
        uhadd8          r5,  r5,  r7
        uhadd8          r8,  r8,  r12
        uhadd8          r9,  r9,  r14
        stm             r0,  {r4,r5}
        add             r0,  r0,  r2
        stm             r0,  {r8,r9}
        add             r0,  r0,  r2
        bne             1b

        pop             {r4-r9, pc}
endfunc

function ff_put_pixels8_y2_no_rnd_armv6, export=1
        push            {r4-r9, lr}
        ldr             r4,  [r1]
        ldr             r5,  [r1, #4]
        ldr             r6,  [r1, r2]!
        ldr             r7,  [r1, #4]
1:
        subs            r3,  r3,  #2
        uhadd8          r8,  r4,  r6
        ldr             r4,  [r1, r2]!
        uhadd8          r9,  r5,  r7
        ldr             r5,  [r1, #4]
        uhadd8          r12, r4,  r6
        ldr             r6,  [r1, r2]!
        uhadd8          r14, r5,  r7
        ldr             r7,  [r1, #4]
        stm             r0,  {r8,r9}
        add             r0,  r0,  r2
        stm             r0,  {r12,r14}
        add             r0,  r0,  r2
        bne             1b

        pop             {r4-r9, pc}
endfunc

function ff_avg_pixels8_armv6, export=1
        pld             [r1, r2]
        push            {r4-r10, lr}
        mov             lr,  #1
        orr             lr,  lr,  lr,  lsl #8
        orr             lr,  lr,  lr,  lsl #16
        ldrd            r4,  r5,  [r0]
        ldr             r10, [r1, #4]
        ldr             r9,  [r1], r2
        subs            r3,  r3,  #2
1:
        pld             [r1, r2]
        eor             r8,  r4,  r9
        uhadd8          r4,  r4,  r9
        eor             r12, r5,  r10
        ldrd            r6,  r7,  [r0, r2]
        uhadd8          r5,  r5,  r10
        and             r8,  r8,  lr
        ldr             r10, [r1, #4]
        and             r12, r12, lr
        uadd8           r4,  r4,  r8
        ldr             r9,  [r1], r2
        eor             r8,  r6,  r9
        uadd8           r5,  r5,  r12
        pld             [r1, r2,  lsl #1]
        eor             r12, r7,  r10
        uhadd8          r6,  r6,  r9
        strd            r4,  r5,  [r0], r2
        uhadd8          r7,  r7,  r10
        beq             2f
        and             r8,  r8,  lr
        ldrd            r4,  r5,  [r0, r2]
        uadd8           r6,  r6,  r8
        ldr             r10, [r1, #4]
        and             r12, r12, lr
        subs            r3,  r3,  #2
        uadd8           r7,  r7,  r12
        ldr             r9,  [r1], r2
        strd            r6,  r7,  [r0], r2
        b               1b
2:
        and             r8,  r8,  lr
        and             r12, r12, lr
        uadd8           r6,  r6,  r8
        uadd8           r7,  r7,  r12
        strd            r6,  r7,  [r0], r2

        pop             {r4-r10, pc}
endfunc

function ff_add_pixels_clamped_armv6, export=1
        push            {r4-r8,lr}
        mov             r3,  #8
1:
        ldm             r0!, {r4,r5,r12,lr}
        ldrd            r6,  r7,  [r1]
        pkhbt           r8,  r4,  r5,  lsl #16
        pkhtb           r5,  r5,  r4,  asr #16
        pkhbt           r4,  r12, lr,  lsl #16
        pkhtb           lr,  lr,  r12, asr #16
        pld             [r1, r2]
        uxtab16         r8,  r8,  r6
        uxtab16         r5,  r5,  r6,  ror #8
        uxtab16         r4,  r4,  r7
        uxtab16         lr,  lr,  r7,  ror #8
        usat16          r8,  #8,  r8
        usat16          r5,  #8,  r5
        usat16          r4,  #8,  r4
        usat16          lr,  #8,  lr
        orr             r6,  r8,  r5,  lsl #8
        orr             r7,  r4,  lr,  lsl #8
        subs            r3,  r3,  #1
        strd            r6,  r7,  [r1],  r2
        bgt             1b
        pop             {r4-r8,pc}
endfunc

function ff_get_pixels_armv6, export=1
        pld             [r1, r2]
        push            {r4-r8, lr}
        mov             lr,  #8
1:
        ldrd            r4,  r5,  [r1],  r2
        subs            lr,  lr,  #1
        uxtb16          r6,  r4
        uxtb16          r4,  r4,  ror #8
        uxtb16          r12, r5
        uxtb16          r8,  r5,  ror #8
        pld             [r1, r2]
        pkhbt           r5,  r6,  r4,  lsl #16
        pkhtb           r6,  r4,  r6,  asr #16
        pkhbt           r7,  r12, r8,  lsl #16
        pkhtb           r12, r8,  r12, asr #16
        stm             r0!, {r5,r6,r7,r12}
        bgt             1b

        pop             {r4-r8, pc}
endfunc

function ff_diff_pixels_armv6, export=1
        pld             [r1, r3]
        pld             [r2, r3]
        push            {r4-r9, lr}
        mov             lr,  #8
1:
        ldrd            r4,  r5,  [r1],  r3
        ldrd            r6,  r7,  [r2],  r3
        uxtb16          r8,  r4
        uxtb16          r4,  r4,  ror #8
        uxtb16          r9,  r6
        uxtb16          r6,  r6,  ror #8
        pld             [r1, r3]
        ssub16          r9,  r8,  r9
        ssub16          r6,  r4,  r6
        uxtb16          r8,  r5
        uxtb16          r5,  r5,  ror #8
        pld             [r2, r3]
        pkhbt           r4,  r9,  r6,  lsl #16
        pkhtb           r6,  r6,  r9,  asr #16
        uxtb16          r9,  r7
        uxtb16          r7,  r7,  ror #8
        ssub16          r9,  r8,  r9
        ssub16          r5,  r5,  r7
        subs            lr,  lr,  #1
        pkhbt           r8,  r9,  r5,  lsl #16
        pkhtb           r9,  r5,  r9,  asr #16
        stm             r0!, {r4,r6,r8,r9}
        bgt             1b

        pop             {r4-r9, pc}
endfunc

function ff_pix_abs16_armv6, export=1
        ldr             r0,  [sp]
        push            {r4-r9, lr}
        mov             r12, #0
        mov             lr,  #0
        ldm             r1,  {r4-r7}
        ldr             r8,  [r2]
1:
        ldr             r9,  [r2, #4]
        pld             [r1, r3]
        usada8          r12, r4,  r8,  r12
        ldr             r8,  [r2, #8]
        pld             [r2, r3]
        usada8          lr,  r5,  r9,  lr
        ldr             r9,  [r2, #12]
        usada8          r12, r6,  r8,  r12
        subs            r0,  r0,  #1
        usada8          lr,  r7,  r9,  lr
        beq             2f
        add             r1,  r1,  r3
        ldm             r1,  {r4-r7}
        add             r2,  r2,  r3
        ldr             r8,  [r2]
        b               1b
2:
        add             r0,  r12, lr
        pop             {r4-r9, pc}
endfunc

function ff_pix_abs16_x2_armv6, export=1
        ldr             r12, [sp]
        push            {r4-r11, lr}
        mov             r0,  #0
        mov             lr,  #1
        orr             lr,  lr,  lr,  lsl #8
        orr             lr,  lr,  lr,  lsl #16
1:
        ldr             r8,  [r2]
        ldr             r9,  [r2, #4]
        lsr             r10, r8,  #8
        ldr             r4,  [r1]
        lsr             r6,  r9,  #8
        orr             r10, r10, r9,  lsl #24
        ldr             r5,  [r2, #8]
        eor             r11, r8,  r10
        uhadd8          r7,  r8,  r10
        orr             r6,  r6,  r5,  lsl #24
        and             r11, r11, lr
        uadd8           r7,  r7,  r11
        ldr             r8,  [r1, #4]
        usada8          r0,  r4,  r7,  r0
        eor             r7,  r9,  r6
        lsr             r10, r5,  #8
        and             r7,  r7,  lr
        uhadd8          r4,  r9,  r6
        ldr             r6,  [r2, #12]
        uadd8           r4,  r4,  r7
        pld             [r1, r3]
        orr             r10, r10, r6,  lsl #24
        usada8          r0,  r8,  r4,  r0
        ldr             r4,  [r1, #8]
        eor             r11, r5,  r10
        ldrb            r7,  [r2, #16]
        and             r11, r11, lr
        uhadd8          r8,  r5,  r10
        ldr             r5,  [r1, #12]
        uadd8           r8,  r8,  r11
        pld             [r2, r3]
        lsr             r10, r6,  #8
        usada8          r0,  r4,  r8,  r0
        orr             r10, r10, r7,  lsl #24
        subs            r12,  r12,  #1
        eor             r11, r6,  r10
        add             r1,  r1,  r3
        uhadd8          r9,  r6,  r10
        and             r11, r11, lr
        uadd8           r9,  r9,  r11
        add             r2,  r2,  r3
        usada8          r0,  r5,  r9,  r0
        bgt             1b

        pop             {r4-r11, pc}
endfunc

.macro  usad_y2         p0,  p1,  p2,  p3,  n0,  n1,  n2,  n3
        ldr             \n0, [r2]
        eor             \n1, \p0, \n0
        uhadd8          \p0, \p0, \n0
        and             \n1, \n1, lr
        ldr             \n2, [r1]
        uadd8           \p0, \p0, \n1
        ldr             \n1, [r2, #4]
        usada8          r0,  \p0, \n2, r0
        pld             [r1,  r3]
        eor             \n3, \p1, \n1
        uhadd8          \p1, \p1, \n1
        and             \n3, \n3, lr
        ldr             \p0, [r1, #4]
        uadd8           \p1, \p1, \n3
        ldr             \n2, [r2, #8]
        usada8          r0,  \p1, \p0, r0
        pld             [r2,  r3]
        eor             \p0, \p2, \n2
        uhadd8          \p2, \p2, \n2
        and             \p0, \p0, lr
        ldr             \p1, [r1, #8]
        uadd8           \p2, \p2, \p0
        ldr             \n3, [r2, #12]
        usada8          r0,  \p2, \p1, r0
        eor             \p1, \p3, \n3
        uhadd8          \p3, \p3, \n3
        and             \p1, \p1, lr
        ldr             \p0,  [r1, #12]
        uadd8           \p3, \p3, \p1
        add             r1,  r1,  r3
        usada8          r0,  \p3, \p0,  r0
        add             r2,  r2,  r3
.endm

function ff_pix_abs16_y2_armv6, export=1
        pld             [r1]
        pld             [r2]
        ldr             r12, [sp]
        push            {r4-r11, lr}
        mov             r0,  #0
        mov             lr,  #1
        orr             lr,  lr,  lr,  lsl #8
        orr             lr,  lr,  lr,  lsl #16
        ldr             r4,  [r2]
        ldr             r5,  [r2, #4]
        ldr             r6,  [r2, #8]
        ldr             r7,  [r2, #12]
        add             r2,  r2,  r3
1:
        usad_y2         r4,  r5,  r6,  r7,  r8,  r9,  r10, r11
        subs            r12, r12, #2
        usad_y2         r8,  r9,  r10, r11, r4,  r5,  r6,  r7
        bgt             1b

        pop             {r4-r11, pc}
endfunc

function ff_pix_abs8_armv6, export=1
        pld             [r2, r3]
        ldr             r12, [sp]
        push            {r4-r9, lr}
        mov             r0,  #0
        mov             lr,  #0
        ldrd            r4,  r5,  [r1], r3
1:
        subs            r12, r12, #2
        ldr             r7,  [r2, #4]
        ldr             r6,  [r2], r3
        ldrd            r8,  r9,  [r1], r3
        usada8          r0,  r4,  r6,  r0
        pld             [r2, r3]
        usada8          lr,  r5,  r7,  lr
        ldr             r7,  [r2, #4]
        ldr             r6,  [r2], r3
        beq             2f
        ldrd            r4,  r5,  [r1], r3
        usada8          r0,  r8,  r6,  r0
        pld             [r2, r3]
        usada8          lr,  r9,  r7,  lr
        b               1b
2:
        usada8          r0,  r8,  r6,  r0
        usada8          lr,  r9,  r7,  lr
        add             r0,  r0,  lr
        pop             {r4-r9, pc}
endfunc

function ff_sse16_armv6, export=1
        ldr             r12, [sp]
        push            {r4-r9, lr}
        mov             r0,  #0
1:
        ldrd            r4,  r5,  [r1]
        ldr             r8,  [r2]
        uxtb16          lr,  r4
        uxtb16          r4,  r4,  ror #8
        uxtb16          r9,  r8
        uxtb16          r8,  r8,  ror #8
        ldr             r7,  [r2, #4]
        usub16          lr,  lr,  r9
        usub16          r4,  r4,  r8
        smlad           r0,  lr,  lr,  r0
        uxtb16          r6,  r5
        uxtb16          lr,  r5,  ror #8
        uxtb16          r8,  r7
        uxtb16          r9,  r7,  ror #8
        smlad           r0,  r4,  r4,  r0
        ldrd            r4,  r5,  [r1, #8]
        usub16          r6,  r6,  r8
        usub16          r8,  lr,  r9
        ldr             r7,  [r2, #8]
        smlad           r0,  r6,  r6,  r0
        uxtb16          lr,  r4
        uxtb16          r4,  r4,  ror #8
        uxtb16          r9,  r7
        uxtb16          r7,  r7, ror #8
        smlad           r0,  r8,  r8,  r0
        ldr             r8,  [r2, #12]
        usub16          lr,  lr,  r9
        usub16          r4,  r4,  r7
        smlad           r0,  lr,  lr,  r0
        uxtb16          r6,  r5
        uxtb16          r5,  r5,  ror #8
        uxtb16          r9,  r8
        uxtb16          r8,  r8,  ror #8
        smlad           r0,  r4,  r4,  r0
        usub16          r6,  r6,  r9
        usub16          r5,  r5,  r8
        smlad           r0,  r6,  r6,  r0
        add             r1,  r1,  r3
        add             r2,  r2,  r3
        subs            r12, r12, #1
        smlad           r0,  r5,  r5,  r0
        bgt             1b

        pop             {r4-r9, pc}
endfunc

function ff_pix_norm1_armv6, export=1
        push            {r4-r6, lr}
        mov             r12, #16
        mov             lr,  #0
1:
        ldm             r0,  {r2-r5}
        uxtb16          r6,  r2
        uxtb16          r2,  r2,  ror #8
        smlad           lr,  r6,  r6,  lr
        uxtb16          r6,  r3
        smlad           lr,  r2,  r2,  lr
        uxtb16          r3,  r3,  ror #8
        smlad           lr,  r6,  r6,  lr
        uxtb16          r6,  r4
        smlad           lr,  r3,  r3,  lr
        uxtb16          r4,  r4,  ror #8
        smlad           lr,  r6,  r6,  lr
        uxtb16          r6,  r5
        smlad           lr,  r4,  r4,  lr
        uxtb16          r5,  r5,  ror #8
        smlad           lr,  r6,  r6,  lr
        subs            r12, r12, #1
        add             r0,  r0,  r1
        smlad           lr,  r5,  r5,  lr
        bgt             1b

        mov             r0,  lr
        pop             {r4-r6, pc}
endfunc

function ff_pix_sum_armv6, export=1
        push            {r4-r7, lr}
        mov             r12, #16
        mov             r2,  #0
        mov             r3,  #0
        mov             lr,  #0
        ldr             r4,  [r0]
1:
        subs            r12, r12, #1
        ldr             r5,  [r0, #4]
        usada8          r2,  r4,  lr,  r2
        ldr             r6,  [r0, #8]
        usada8          r3,  r5,  lr,  r3
        ldr             r7,  [r0, #12]
        usada8          r2,  r6,  lr,  r2
        beq             2f
        ldr             r4,  [r0, r1]!
        usada8          r3,  r7,  lr,  r3
        bgt             1b
2:
        usada8          r3,  r7,  lr,  r3
        add             r0,  r2,  r3
        pop             {r4-r7, pc}
endfunc