/*
* Alpha optimized DSP utils
* Copyright (c) 2002 Falk Hueffner <falk@debian.org>
*
* 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 "regdef.h"
/* Some nicer register names. */
#define ta t10
#define tb t11
#define tc t12
#define td AT
/* Danger: these overlap with the argument list and the return value */
#define te a5
#define tf a4
#define tg a3
#define th v0
.set noat
.set noreorder
.arch pca56
.text
/*****************************************************************************
* int pix_abs16x16_mvi_asm(uint8_t *pix1, uint8_t *pix2, int line_size)
*
* This code is written with a pca56 in mind. For ev6, one should
* really take the increased latency of 3 cycles for MVI instructions
* into account.
*
* It is important to keep the loading and first use of a register as
* far apart as possible, because if a register is accessed before it
* has been fetched from memory, the CPU will stall.
*/
.align 4
.globl pix_abs16x16_mvi_asm
.ent pix_abs16x16_mvi_asm
pix_abs16x16_mvi_asm:
.frame sp, 0, ra, 0
.prologue 0
and a2, 7, t0
clr v0
beq t0, $aligned
.align 4
$unaligned:
/* Registers:
line 0:
t0: left_u -> left lo -> left
t1: mid
t2: right_u -> right hi -> right
t3: ref left
t4: ref right
line 1:
t5: left_u -> left lo -> left
t6: mid
t7: right_u -> right hi -> right
t8: ref left
t9: ref right
temp:
ta: left hi
tb: right lo
tc: error left
td: error right */
/* load line 0 */
ldq_u t0, 0(a2) # left_u
ldq_u t1, 8(a2) # mid
ldq_u t2, 16(a2) # right_u
ldq t3, 0(a1) # ref left
ldq t4, 8(a1) # ref right
addq a1, a3, a1 # pix1
addq a2, a3, a2 # pix2
/* load line 1 */
ldq_u t5, 0(a2) # left_u
ldq_u t6, 8(a2) # mid
ldq_u t7, 16(a2) # right_u
ldq t8, 0(a1) # ref left
ldq t9, 8(a1) # ref right
addq a1, a3, a1 # pix1
addq a2, a3, a2 # pix2
/* calc line 0 */
extql t0, a2, t0 # left lo
extqh t1, a2, ta # left hi
extql t1, a2, tb # right lo
or t0, ta, t0 # left
extqh t2, a2, t2 # right hi
perr t3, t0, tc # error left
or t2, tb, t2 # right
perr t4, t2, td # error right
addq v0, tc, v0 # add error left
addq v0, td, v0 # add error left
/* calc line 1 */
extql t5, a2, t5 # left lo
extqh t6, a2, ta # left hi
extql t6, a2, tb # right lo
or t5, ta, t5 # left
extqh t7, a2, t7 # right hi
perr t8, t5, tc # error left
or t7, tb, t7 # right
perr t9, t7, td # error right
addq v0, tc, v0 # add error left
addq v0, td, v0 # add error left
/* loop */
subq a4, 2, a4 # h -= 2
bne a4, $unaligned
ret
.align 4
$aligned:
/* load line 0 */
ldq t0, 0(a2) # left
ldq t1, 8(a2) # right
addq a2, a3, a2 # pix2
ldq t2, 0(a1) # ref left
ldq t3, 8(a1) # ref right
addq a1, a3, a1 # pix1
/* load line 1 */
ldq t4, 0(a2) # left
ldq t5, 8(a2) # right
addq a2, a3, a2 # pix2
ldq t6, 0(a1) # ref left
ldq t7, 8(a1) # ref right
addq a1, a3, a1 # pix1
/* load line 2 */
ldq t8, 0(a2) # left
ldq t9, 8(a2) # right
addq a2, a3, a2 # pix2
ldq ta, 0(a1) # ref left
ldq tb, 8(a1) # ref right
addq a1, a3, a1 # pix1
/* load line 3 */
ldq tc, 0(a2) # left
ldq td, 8(a2) # right
addq a2, a3, a2 # pix2
ldq te, 0(a1) # ref left
ldq a0, 8(a1) # ref right
/* calc line 0 */
perr t0, t2, t0 # error left
addq a1, a3, a1 # pix1
perr t1, t3, t1 # error right
addq v0, t0, v0 # add error left
/* calc line 1 */
perr t4, t6, t0 # error left
addq v0, t1, v0 # add error right
perr t5, t7, t1 # error right
addq v0, t0, v0 # add error left
/* calc line 2 */
perr t8, ta, t0 # error left
addq v0, t1, v0 # add error right
perr t9, tb, t1 # error right
addq v0, t0, v0 # add error left
/* calc line 3 */
perr tc, te, t0 # error left
addq v0, t1, v0 # add error right
perr td, a0, t1 # error right
addq v0, t0, v0 # add error left
addq v0, t1, v0 # add error right
/* loop */
subq a4, 4, a4 # h -= 4
bne a4, $aligned
ret
.end pix_abs16x16_mvi_asm