ffmpeg-bb/libavcodec/ppc/pixblockdsp.c
Andreas Rheinhardt 20ddada2a3 avcodec/pixblockdsp: Improve 8 vs 16 bit check
Before this commit, the input in get_pixels and get_pixels_unaligned
has been treated inconsistenly:
- The generic code treated 9, 10, 12 and 14 bits as 16bit input
(these bits correspond to what FFmpeg's dsputils supported),
everything with <= 8 bits as 8 bit and everything else as 8 bit
when used via AVDCT (which exposes these functions and purports
to support up to 14 bits).
- AARCH64, ARM, PPC and RISC-V, x86 ignore this AVDCT special case.
- RISC-V also ignored the restriction to 9, 10, 12 and 14 for its
16bit check and treated everything > 8 bits as 16bit.
- The mmi MIPS code treats everything as 8 bit when used via
AVDCT (this is certainly broken); otherwise it checks for <= 8 bits.
The msa MIPS code behaves like the generic code.

This commit changes this to treat 9..16 bits as 16 bit input,
everything else as 8 bit (the former because it makes sense,
the latter to preserve the behaviour for external users*).

*: The only internal user of AVDCT (the spp filter) always
uses 8, 9 or 10 bits.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2025-05-31 01:25:27 +02:00

288 lines
8.4 KiB
C

/*
* Copyright (c) 2002 Brian Foley
* Copyright (c) 2002 Dieter Shirley
* Copyright (c) 2003-2004 Romain Dolbeau <romain@dolbeau.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 "config.h"
#include "libavutil/attributes.h"
#include "libavutil/cpu.h"
#include "libavutil/ppc/cpu.h"
#include "libavutil/ppc/util_altivec.h"
#include "libavcodec/pixblockdsp.h"
#if HAVE_ALTIVEC
#if HAVE_VSX
static void get_pixels_altivec(int16_t *restrict block, const uint8_t *pixels,
ptrdiff_t stride)
{
int i;
vector unsigned char perm =
(vector unsigned char) {0x00,0x10, 0x01,0x11,0x02,0x12,0x03,0x13,\
0x04,0x14,0x05,0x15,0x06,0x16,0x07,0x17};
const vector unsigned char zero =
(const vector unsigned char) vec_splat_u8(0);
for (i = 0; i < 8; i++) {
/* Read potentially unaligned pixels.
* We're reading 16 pixels, and actually only want 8,
* but we simply ignore the extras. */
vector unsigned char bytes = vec_vsx_ld(0, pixels);
// Convert the bytes into shorts.
//vector signed short shorts = (vector signed short) vec_perm(zero, bytes, perm);
vector signed short shorts = (vector signed short) vec_perm(bytes, zero, perm);
// Save the data to the block, we assume the block is 16-byte aligned.
vec_vsx_st(shorts, i * 16, (vector signed short *) block);
pixels += stride;
}
}
#else
static void get_pixels_altivec(int16_t *restrict block, const uint8_t *pixels,
ptrdiff_t stride)
{
int i;
const vec_u8 zero = (const vec_u8)vec_splat_u8(0);
for (i = 0; i < 8; i++) {
vec_u8 perm = vec_lvsl(0, pixels);
/* Read potentially unaligned pixels.
* We're reading 16 pixels, and actually only want 8,
* but we simply ignore the extras. */
vec_u8 pixl = vec_ld(0, pixels);
vec_u8 pixr = vec_ld(7, pixels);
vec_u8 bytes = vec_perm(pixl, pixr, perm);
// Convert the bytes into shorts.
vec_s16 shorts = (vec_s16)vec_mergeh(zero, bytes);
// Save the data to the block, we assume the block is 16-byte aligned.
vec_st(shorts, i * 16, (vec_s16 *)block);
pixels += stride;
}
}
#endif /* HAVE_VSX */
#if HAVE_VSX
static void diff_pixels_altivec(int16_t *restrict block, const uint8_t *s1,
const uint8_t *s2, ptrdiff_t stride)
{
int i;
const vector unsigned char zero =
(const vector unsigned char) vec_splat_u8(0);
vector signed short shorts1, shorts2;
for (i = 0; i < 4; i++) {
/* Read potentially unaligned pixels.
* We're reading 16 pixels, and actually only want 8,
* but we simply ignore the extras. */
vector unsigned char bytes = vec_vsx_ld(0, s1);
// Convert the bytes into shorts.
shorts1 = (vector signed short) vec_mergeh(bytes, zero);
// Do the same for the second block of pixels.
bytes =vec_vsx_ld(0, s2);
// Convert the bytes into shorts.
shorts2 = (vector signed short) vec_mergeh(bytes, zero);
// Do the subtraction.
shorts1 = vec_sub(shorts1, shorts2);
// Save the data to the block, we assume the block is 16-byte aligned.
vec_vsx_st(shorts1, 0, (vector signed short *) block);
s1 += stride;
s2 += stride;
block += 8;
/* The code below is a copy of the code above...
* This is a manual unroll. */
/* Read potentially unaligned pixels.
* We're reading 16 pixels, and actually only want 8,
* but we simply ignore the extras. */
bytes = vec_vsx_ld(0, s1);
// Convert the bytes into shorts.
shorts1 = (vector signed short) vec_mergeh(bytes, zero);
// Do the same for the second block of pixels.
bytes = vec_vsx_ld(0, s2);
// Convert the bytes into shorts.
shorts2 = (vector signed short) vec_mergeh(bytes, zero);
// Do the subtraction.
shorts1 = vec_sub(shorts1, shorts2);
// Save the data to the block, we assume the block is 16-byte aligned.
vec_vsx_st(shorts1, 0, (vector signed short *) block);
s1 += stride;
s2 += stride;
block += 8;
}
}
#else
static void diff_pixels_altivec(int16_t *restrict block, const uint8_t *s1,
const uint8_t *s2, ptrdiff_t stride)
{
int i;
vec_u8 perm;
const vec_u8 zero = (const vec_u8)vec_splat_u8(0);
vec_s16 shorts1, shorts2;
for (i = 0; i < 4; i++) {
/* Read potentially unaligned pixels.
* We're reading 16 pixels, and actually only want 8,
* but we simply ignore the extras. */
perm = vec_lvsl(0, s1);
vec_u8 pixl = vec_ld(0, s1);
vec_u8 pixr = vec_ld(15, s1);
vec_u8 bytes = vec_perm(pixl, pixr, perm);
// Convert the bytes into shorts.
shorts1 = (vec_s16)vec_mergeh(zero, bytes);
// Do the same for the second block of pixels.
perm = vec_lvsl(0, s2);
pixl = vec_ld(0, s2);
pixr = vec_ld(15, s2);
bytes = vec_perm(pixl, pixr, perm);
// Convert the bytes into shorts.
shorts2 = (vec_s16)vec_mergeh(zero, bytes);
// Do the subtraction.
shorts1 = vec_sub(shorts1, shorts2);
// Save the data to the block, we assume the block is 16-byte aligned.
vec_st(shorts1, 0, (vec_s16 *)block);
s1 += stride;
s2 += stride;
block += 8;
/* The code below is a copy of the code above...
* This is a manual unroll. */
/* Read potentially unaligned pixels.
* We're reading 16 pixels, and actually only want 8,
* but we simply ignore the extras. */
perm = vec_lvsl(0, s1);
pixl = vec_ld(0, s1);
pixr = vec_ld(15, s1);
bytes = vec_perm(pixl, pixr, perm);
// Convert the bytes into shorts.
shorts1 = (vec_s16)vec_mergeh(zero, bytes);
// Do the same for the second block of pixels.
perm = vec_lvsl(0, s2);
pixl = vec_ld(0, s2);
pixr = vec_ld(15, s2);
bytes = vec_perm(pixl, pixr, perm);
// Convert the bytes into shorts.
shorts2 = (vec_s16)vec_mergeh(zero, bytes);
// Do the subtraction.
shorts1 = vec_sub(shorts1, shorts2);
// Save the data to the block, we assume the block is 16-byte aligned.
vec_st(shorts1, 0, (vec_s16 *)block);
s1 += stride;
s2 += stride;
block += 8;
}
}
#endif /* HAVE_VSX */
#endif /* HAVE_ALTIVEC */
#if HAVE_VSX
static void get_pixels_vsx(int16_t *restrict block, const uint8_t *pixels,
ptrdiff_t stride)
{
int i;
for (i = 0; i < 8; i++) {
vec_s16 shorts = vsx_ld_u8_s16(0, pixels);
vec_vsx_st(shorts, i * 16, block);
pixels += stride;
}
}
static void diff_pixels_vsx(int16_t *restrict block, const uint8_t *s1,
const uint8_t *s2, ptrdiff_t stride)
{
int i;
vec_s16 shorts1, shorts2;
for (i = 0; i < 8; i++) {
shorts1 = vsx_ld_u8_s16(0, s1);
shorts2 = vsx_ld_u8_s16(0, s2);
shorts1 = vec_sub(shorts1, shorts2);
vec_vsx_st(shorts1, 0, block);
s1 += stride;
s2 += stride;
block += 8;
}
}
#endif /* HAVE_VSX */
av_cold void ff_pixblockdsp_init_ppc(PixblockDSPContext *c,
unsigned high_bit_depth)
{
#if HAVE_ALTIVEC
if (!PPC_ALTIVEC(av_get_cpu_flags()))
return;
c->diff_pixels = diff_pixels_altivec;
if (!high_bit_depth) {
c->get_pixels = get_pixels_altivec;
}
#endif /* HAVE_ALTIVEC */
#if HAVE_VSX
if (!PPC_VSX(av_get_cpu_flags()))
return;
c->diff_pixels = diff_pixels_vsx;
if (!high_bit_depth)
c->get_pixels = get_pixels_vsx;
#endif /* HAVE_VSX */
}