PeerStreamer

/*

 * Copyright (c) 2008 Siarhei Siamashka <ssvb@users.sourceforge.net>

 *

 * 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 "config.h"

#include "asm.S"

        .fpu neon       @ required for gas to accept UAL syntax

/*

 * VFP is a floating point coprocessor used in some ARM cores. VFP11 has 1 cycle

 * throughput for almost all the instructions (except for double precision

 * arithmetics), but rather high latency. Latency is 4 cycles for loads and 8 cycles

 * for arithmetic operations. Scheduling code to avoid pipeline stalls is very

 * important for performance. One more interesting feature is that VFP has

 * independent load/store and arithmetics pipelines, so it is possible to make

 * them work simultaneously and get more than 1 operation per cycle. Load/store

 * pipeline can process 2 single precision floating point values per cycle and

 * supports bulk loads and stores for large sets of registers. Arithmetic operations

 * can be done on vectors, which allows to keep the arithmetics pipeline busy,

 * while the processor may issue and execute other instructions. Detailed

 * optimization manuals can be found at http://www.arm.com

 */

/**

 * ARM VFP optimized implementation of 'vector_fmul_c' function.

 * Assume that len is a positive number and is multiple of 8

 */

@ void ff_vector_fmul_vfp(float *dst, const float *src, int len)

function ff_vector_fmul_vfp, export=1

        vpush           {d8-d15}

        mov             r3,  r0

        fmrx            r12, fpscr

        orr             r12, r12, #(3 << 16) /* set vector size to 4 */

        fmxr            fpscr, r12

        vldmia          r3!, {s0-s3}

        vldmia          r1!, {s8-s11}

        vldmia          r3!, {s4-s7}

        vldmia          r1!, {s12-s15}

        vmul.f32        s8,  s0,  s8

1:

        subs            r2,  r2,  #16

        vmul.f32        s12, s4,  s12

        vldmiage        r3!, {s16-s19}

        vldmiage        r1!, {s24-s27}

        vldmiage        r3!, {s20-s23}

        vldmiage        r1!, {s28-s31}

        vmulge.f32      s24, s16, s24

        vstmia          r0!, {s8-s11}

        vstmia          r0!, {s12-s15}

        vmulge.f32      s28, s20, s28

        vldmiagt        r3!, {s0-s3}

        vldmiagt        r1!, {s8-s11}

        vldmiagt        r3!, {s4-s7}

        vldmiagt        r1!, {s12-s15}

        vmulge.f32      s8,  s0,  s8

        vstmiage        r0!, {s24-s27}

        vstmiage        r0!, {s28-s31}

        bgt             1b

        bic             r12, r12, #(7 << 16) /* set vector size back to 1 */

        fmxr            fpscr, r12

        vpop            {d8-d15}

        bx              lr

        .endfunc

/**

 * ARM VFP optimized implementation of 'vector_fmul_reverse_c' function.

 * Assume that len is a positive number and is multiple of 8

 */

@ void ff_vector_fmul_reverse_vfp(float *dst, const float *src0,

@                                 const float *src1, int len)

function ff_vector_fmul_reverse_vfp, export=1

        vpush           {d8-d15}

        add             r2,  r2,  r3, lsl #2

        vldmdb          r2!, {s0-s3}

        vldmia          r1!, {s8-s11}

        vldmdb          r2!, {s4-s7}

        vldmia          r1!, {s12-s15}

        vmul.f32        s8,  s3,  s8

        vmul.f32        s9,  s2,  s9

        vmul.f32        s10, s1,  s10

        vmul.f32        s11, s0,  s11

1:

        subs            r3,  r3,  #16

        vldmdbge        r2!, {s16-s19}

        vmul.f32        s12, s7,  s12

        vldmiage        r1!, {s24-s27}

        vmul.f32        s13, s6,  s13

        vldmdbge        r2!, {s20-s23}

        vmul.f32        s14, s5,  s14

        vldmiage        r1!, {s28-s31}

        vmul.f32        s15, s4,  s15

        vmulge.f32      s24, s19, s24

        vldmdbgt        r2!, {s0-s3}

        vmulge.f32      s25, s18, s25

        vstmia          r0!, {s8-s13}

        vmulge.f32      s26, s17, s26

        vldmiagt        r1!, {s8-s11}

        vmulge.f32      s27, s16, s27

        vmulge.f32      s28, s23, s28

        vldmdbgt        r2!, {s4-s7}

        vmulge.f32      s29, s22, s29

        vstmia          r0!, {s14-s15}

        vmulge.f32      s30, s21, s30

        vmulge.f32      s31, s20, s31

        vmulge.f32      s8,  s3,  s8

        vldmiagt        r1!, {s12-s15}

        vmulge.f32      s9,  s2,  s9

        vmulge.f32      s10, s1,  s10

        vstmiage        r0!, {s24-s27}

        vmulge.f32      s11, s0,  s11

        vstmiage        r0!, {s28-s31}

        bgt             1b

        vpop            {d8-d15}

        bx              lr

        .endfunc

#ifdef HAVE_ARMV6

/**

 * ARM VFP optimized float to int16 conversion.

 * Assume that len is a positive number and is multiple of 8, destination

 * buffer is at least 4 bytes aligned (8 bytes alignment is better for

 * performance), little endian byte sex

 */

@ void ff_float_to_int16_vfp(int16_t *dst, const float *src, int len)

function ff_float_to_int16_vfp, export=1

        push            {r4-r8,lr}

        vpush           {d8-d11}

        vldmia          r1!, {s16-s23}

        vcvt.s32.f32    s0,  s16

        vcvt.s32.f32    s1,  s17

        vcvt.s32.f32    s2,  s18

        vcvt.s32.f32    s3,  s19

        vcvt.s32.f32    s4,  s20

        vcvt.s32.f32    s5,  s21

        vcvt.s32.f32    s6,  s22

        vcvt.s32.f32    s7,  s23

1:

        subs            r2,  r2,  #8

        vmov            r3,  r4,  s0, s1

        vmov            r5,  r6,  s2, s3

        vmov            r7,  r8,  s4, s5

        vmov            ip,  lr,  s6, s7

        vldmiagt        r1!, {s16-s23}

        ssat            r4,  #16, r4

        ssat            r3,  #16, r3

        ssat            r6,  #16, r6

        ssat            r5,  #16, r5

        pkhbt           r3,  r3,  r4, lsl #16

        pkhbt           r4,  r5,  r6, lsl #16

        vcvtgt.s32.f32  s0,  s16

        vcvtgt.s32.f32  s1,  s17

        vcvtgt.s32.f32  s2,  s18

        vcvtgt.s32.f32  s3,  s19

        vcvtgt.s32.f32  s4,  s20

        vcvtgt.s32.f32  s5,  s21

        vcvtgt.s32.f32  s6,  s22

        vcvtgt.s32.f32  s7,  s23

        ssat            r8,  #16, r8

        ssat            r7,  #16, r7

        ssat            lr,  #16, lr

        ssat            ip,  #16, ip

        pkhbt           r5,  r7,  r8, lsl #16

        pkhbt           r6,  ip,  lr, lsl #16

        stmia           r0!, {r3-r6}

        bgt             1b

        vpop            {d8-d11}

        pop             {r4-r8,pc}

        .endfunc

#endif