ffmpeg/libavcodec/ppc/vp8dsp_altivec.c
Andreas Rheinhardt 09e6840cf7 avcodec/ppc/vp8dsp_altivec: Fix out-of-bounds access
h_subpel_filters_inner[i] and h_subpel_filters_outer[i / 2]
belong together and the former allows the range 0..6,
so the latter needs to support 0..3. But it has only three
elements. Add another one.
The value for the last element has been guesstimated
from subpel_filters in libavcodec/vp8dsp.c.

This is also intended to fix FATE-failures with UBSan here:
https://fate.ffmpeg.org/report.cgi?time=20240312011016&slot=ppc-linux-gcc-13.2-ubsan-altivec-qemu

Tested-by: Sean McGovern <gseanmcg@gmail.com>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2024-03-14 22:20:00 +01:00

364 lines
12 KiB
C

/*
* VP8 compatible video decoder
*
* Copyright (C) 2010 David Conrad
*
* 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/mem_internal.h"
#include "libavutil/ppc/cpu.h"
#include "libavutil/ppc/util_altivec.h"
#include "libavcodec/vp8dsp.h"
#include "hpeldsp_altivec.h"
#if HAVE_ALTIVEC
#define REPT4(...) { __VA_ARGS__, __VA_ARGS__, __VA_ARGS__, __VA_ARGS__ }
// h subpel filter uses msum to multiply+add 4 pixel taps at once
static const vec_s8 h_subpel_filters_inner[7] =
{
REPT4( -6, 123, 12, -1),
REPT4(-11, 108, 36, -8),
REPT4( -9, 93, 50, -6),
REPT4(-16, 77, 77, -16),
REPT4( -6, 50, 93, -9),
REPT4( -8, 36, 108, -11),
REPT4( -1, 12, 123, -6),
};
// for 6tap filters, these are the outer two taps
// The zeros mask off pixels 4-7 when filtering 0-3
// and vice-versa
static const vec_s8 h_subpel_filters_outer[4] =
{
REPT4(0, 0, 2, 1),
REPT4(0, 0, 3, 3),
REPT4(0, 0, 1, 2),
REPT4(0, 0, 0, 0),
};
#define LOAD_H_SUBPEL_FILTER(i) \
vec_s8 filter_inner = h_subpel_filters_inner[i]; \
vec_s8 filter_outerh = h_subpel_filters_outer[(i)>>1]; \
vec_s8 filter_outerl = vec_sld(filter_outerh, filter_outerh, 2)
#if HAVE_BIGENDIAN
#define GET_PIXHL(offset) \
a = vec_ld((offset)-is6tap-1, src); \
b = vec_ld((offset)-is6tap-1+15, src); \
pixh = vec_perm(a, b, permh##offset); \
pixl = vec_perm(a, b, perml##offset)
#define GET_OUTER(offset) outer = vec_perm(a, b, perm_6tap##offset)
#else
#define GET_PIXHL(offset) \
a = vec_vsx_ld((offset)-is6tap-1, src); \
pixh = vec_perm(a, a, perm_inner); \
pixl = vec_perm(a, a, vec_add(perm_inner, vec_splat_u8(4)))
#define GET_OUTER(offset) outer = vec_perm(a, a, perm_outer)
#endif
#define FILTER_H(dstv, off) \
GET_PIXHL(off); \
filth = vec_msum(filter_inner, pixh, c64); \
filtl = vec_msum(filter_inner, pixl, c64); \
\
if (is6tap) { \
GET_OUTER(off); \
filth = vec_msum(filter_outerh, outer, filth); \
filtl = vec_msum(filter_outerl, outer, filtl); \
} \
if (w == 4) \
filtl = filth; /* discard pixels 4-7 */ \
dstv = vec_packs(filth, filtl); \
dstv = vec_sra(dstv, c7)
static av_always_inline
void put_vp8_epel_h_altivec_core(uint8_t *dst, ptrdiff_t dst_stride,
const uint8_t *src, ptrdiff_t src_stride,
int h, int mx, int w, int is6tap)
{
LOAD_H_SUBPEL_FILTER(mx-1);
#if HAVE_BIGENDIAN
vec_u8 align_vec0, align_vec8, permh0, permh8;
vec_u8 perm_6tap0, perm_6tap8, perml0, perml8;
vec_u8 b;
#endif
vec_u8 filt, a, pixh, pixl, outer;
vec_s16 f16h, f16l;
vec_s32 filth, filtl;
vec_u8 perm_inner6 = { 1,2,3,4, 2,3,4,5, 3,4,5,6, 4,5,6,7 };
vec_u8 perm_inner4 = { 0,1,2,3, 1,2,3,4, 2,3,4,5, 3,4,5,6 };
vec_u8 perm_inner = is6tap ? perm_inner6 : perm_inner4;
vec_u8 perm_outer = { 4,9, 0,5, 5,10, 1,6, 6,11, 2,7, 7,12, 3,8 };
vec_s32 c64 = vec_sl(vec_splat_s32(1), vec_splat_u32(6));
vec_u16 c7 = vec_splat_u16(7);
#if HAVE_BIGENDIAN
align_vec0 = vec_lvsl( -is6tap-1, src);
align_vec8 = vec_lvsl(8-is6tap-1, src);
permh0 = vec_perm(align_vec0, align_vec0, perm_inner);
permh8 = vec_perm(align_vec8, align_vec8, perm_inner);
perm_inner = vec_add(perm_inner, vec_splat_u8(4));
perml0 = vec_perm(align_vec0, align_vec0, perm_inner);
perml8 = vec_perm(align_vec8, align_vec8, perm_inner);
perm_6tap0 = vec_perm(align_vec0, align_vec0, perm_outer);
perm_6tap8 = vec_perm(align_vec8, align_vec8, perm_outer);
#endif
while (h --> 0) {
FILTER_H(f16h, 0);
if (w == 16) {
FILTER_H(f16l, 8);
filt = vec_packsu(f16h, f16l);
vec_st(filt, 0, dst);
} else {
filt = vec_packsu(f16h, f16h);
vec_ste((vec_u32)filt, 0, (uint32_t*)dst);
if (w == 8)
vec_ste((vec_u32)filt, 4, (uint32_t*)dst);
}
src += src_stride;
dst += dst_stride;
}
}
// v subpel filter does a simple vertical multiply + add
static const vec_u8 v_subpel_filters[7] =
{
{ 0, 6, 123, 12, 1, 0 },
{ 2, 11, 108, 36, 8, 1 },
{ 0, 9, 93, 50, 6, 0 },
{ 3, 16, 77, 77, 16, 3 },
{ 0, 6, 50, 93, 9, 0 },
{ 1, 8, 36, 108, 11, 2 },
{ 0, 1, 12, 123, 6, 0 },
};
#define LOAD_V_SUBPEL_FILTER(i) \
vec_u8 subpel_filter = v_subpel_filters[i]; \
vec_u8 f0 = vec_splat(subpel_filter, 0); \
vec_u8 f1 = vec_splat(subpel_filter, 1); \
vec_u8 f2 = vec_splat(subpel_filter, 2); \
vec_u8 f3 = vec_splat(subpel_filter, 3); \
vec_u8 f4 = vec_splat(subpel_filter, 4); \
vec_u8 f5 = vec_splat(subpel_filter, 5)
#define FILTER_V(dstv, vec_mul) \
s1f = (vec_s16)vec_mul(s1, f1); \
s2f = (vec_s16)vec_mul(s2, f2); \
s3f = (vec_s16)vec_mul(s3, f3); \
s4f = (vec_s16)vec_mul(s4, f4); \
s2f = vec_subs(s2f, s1f); \
s3f = vec_subs(s3f, s4f); \
if (is6tap) { \
s0f = (vec_s16)vec_mul(s0, f0); \
s5f = (vec_s16)vec_mul(s5, f5); \
s2f = vec_adds(s2f, s0f); \
s3f = vec_adds(s3f, s5f); \
} \
dstv = vec_adds(s2f, s3f); \
dstv = vec_adds(dstv, c64); \
dstv = vec_sra(dstv, c7)
#if HAVE_BIGENDIAN
#define LOAD_HL(off, s, perm) load_with_perm_vec(off, s, perm)
#else
#define LOAD_HL(off, s, perm) vec_mergeh(vec_vsx_ld(off,s), vec_vsx_ld(off+8,s))
#endif
static av_always_inline
void put_vp8_epel_v_altivec_core(uint8_t *dst, ptrdiff_t dst_stride,
const uint8_t *src, ptrdiff_t src_stride,
int h, int my, int w, int is6tap)
{
LOAD_V_SUBPEL_FILTER(my-1);
vec_u8 s0, s1, s2, s3, s4, s5, filt, align_vech, perm_vec, align_vecl;
vec_s16 s0f, s1f, s2f, s3f, s4f, s5f, f16h, f16l;
vec_s16 c64 = vec_sl(vec_splat_s16(1), vec_splat_u16(6));
vec_u16 c7 = vec_splat_u16(7);
#if HAVE_BIGENDIAN
// we want pixels 0-7 to be in the even positions and 8-15 in the odd,
// so combine this permute with the alignment permute vector
align_vech = vec_lvsl(0, src);
align_vecl = vec_sld(align_vech, align_vech, 8);
if (w ==16)
perm_vec = vec_mergeh(align_vech, align_vecl);
else
perm_vec = vec_mergeh(align_vech, align_vech);
#endif
if (is6tap)
s0 = LOAD_HL(-2*src_stride, src, perm_vec);
s1 = LOAD_HL(-1*src_stride, src, perm_vec);
s2 = LOAD_HL( 0*src_stride, src, perm_vec);
s3 = LOAD_HL( 1*src_stride, src, perm_vec);
if (is6tap)
s4 = LOAD_HL( 2*src_stride, src, perm_vec);
src += (2+is6tap)*src_stride;
while (h --> 0) {
if (is6tap)
s5 = LOAD_HL(0, src, perm_vec);
else
s4 = LOAD_HL(0, src, perm_vec);
FILTER_V(f16h, vec_mule);
if (w == 16) {
FILTER_V(f16l, vec_mulo);
filt = vec_packsu(f16h, f16l);
vec_st(filt, 0, dst);
} else {
filt = vec_packsu(f16h, f16h);
if (w == 4)
filt = (vec_u8)vec_splat((vec_u32)filt, 0);
else
vec_ste((vec_u32)filt, 4, (uint32_t*)dst);
vec_ste((vec_u32)filt, 0, (uint32_t*)dst);
}
if (is6tap)
s0 = s1;
s1 = s2;
s2 = s3;
s3 = s4;
if (is6tap)
s4 = s5;
dst += dst_stride;
src += src_stride;
}
}
#define EPEL_FUNCS(WIDTH, TAPS) \
static av_noinline \
void put_vp8_epel ## WIDTH ## _h ## TAPS ## _altivec(uint8_t *dst, ptrdiff_t dst_stride, const uint8_t *src, ptrdiff_t src_stride, int h, int mx, int my) \
{ \
put_vp8_epel_h_altivec_core(dst, dst_stride, src, src_stride, h, mx, WIDTH, TAPS == 6); \
} \
\
static av_noinline \
void put_vp8_epel ## WIDTH ## _v ## TAPS ## _altivec(uint8_t *dst, ptrdiff_t dst_stride, const uint8_t *src, ptrdiff_t src_stride, int h, int mx, int my) \
{ \
put_vp8_epel_v_altivec_core(dst, dst_stride, src, src_stride, h, my, WIDTH, TAPS == 6); \
}
#define EPEL_HV(WIDTH, HTAPS, VTAPS) \
static void put_vp8_epel ## WIDTH ## _h ## HTAPS ## v ## VTAPS ## _altivec(uint8_t *dst, ptrdiff_t dstride, const uint8_t *src, ptrdiff_t sstride, int h, int mx, int my) \
{ \
DECLARE_ALIGNED(16, uint8_t, tmp)[(2*WIDTH+5)*16]; \
if (VTAPS == 6) { \
put_vp8_epel ## WIDTH ## _h ## HTAPS ## _altivec(tmp, 16, src-2*sstride, sstride, h+5, mx, my); \
put_vp8_epel ## WIDTH ## _v ## VTAPS ## _altivec(dst, dstride, tmp+2*16, 16, h, mx, my); \
} else { \
put_vp8_epel ## WIDTH ## _h ## HTAPS ## _altivec(tmp, 16, src-sstride, sstride, h+4, mx, my); \
put_vp8_epel ## WIDTH ## _v ## VTAPS ## _altivec(dst, dstride, tmp+16, 16, h, mx, my); \
} \
}
EPEL_FUNCS(16,6)
EPEL_FUNCS(8, 6)
EPEL_FUNCS(8, 4)
EPEL_FUNCS(4, 6)
EPEL_FUNCS(4, 4)
EPEL_HV(16, 6,6)
EPEL_HV(8, 6,6)
EPEL_HV(8, 4,6)
EPEL_HV(8, 6,4)
EPEL_HV(8, 4,4)
EPEL_HV(4, 6,6)
EPEL_HV(4, 4,6)
EPEL_HV(4, 6,4)
EPEL_HV(4, 4,4)
static void put_vp8_pixels16_altivec(uint8_t *dst, ptrdiff_t dstride, const uint8_t *src, ptrdiff_t sstride, int h, int mx, int my)
{
register vector unsigned char perm;
int i;
register ptrdiff_t dstride2 = dstride << 1, sstride2 = sstride << 1;
register ptrdiff_t dstride3 = dstride2 + dstride, sstride3 = sstride + sstride2;
register ptrdiff_t dstride4 = dstride << 2, sstride4 = sstride << 2;
#if HAVE_BIGENDIAN
perm = vec_lvsl(0, src);
#endif
// hand-unrolling the loop by 4 gains about 15%
// mininum execution time goes from 74 to 60 cycles
// it's faster than -funroll-loops, but using
// -funroll-loops w/ this is bad - 74 cycles again.
// all this is on a 7450, tuning for the 7450
for (i = 0; i < h; i += 4) {
vec_st(load_with_perm_vec(0, src, perm), 0, dst);
vec_st(load_with_perm_vec(sstride, src, perm), dstride, dst);
vec_st(load_with_perm_vec(sstride2, src, perm), dstride2, dst);
vec_st(load_with_perm_vec(sstride3, src, perm), dstride3, dst);
src += sstride4;
dst += dstride4;
}
}
#endif /* HAVE_ALTIVEC */
av_cold void ff_vp78dsp_init_ppc(VP8DSPContext *c)
{
#if HAVE_ALTIVEC
if (!PPC_ALTIVEC(av_get_cpu_flags()))
return;
c->put_vp8_epel_pixels_tab[0][0][0] = put_vp8_pixels16_altivec;
c->put_vp8_epel_pixels_tab[0][0][2] = put_vp8_epel16_h6_altivec;
c->put_vp8_epel_pixels_tab[0][2][0] = put_vp8_epel16_v6_altivec;
c->put_vp8_epel_pixels_tab[0][2][2] = put_vp8_epel16_h6v6_altivec;
c->put_vp8_epel_pixels_tab[1][0][2] = put_vp8_epel8_h6_altivec;
c->put_vp8_epel_pixels_tab[1][2][0] = put_vp8_epel8_v6_altivec;
c->put_vp8_epel_pixels_tab[1][0][1] = put_vp8_epel8_h4_altivec;
c->put_vp8_epel_pixels_tab[1][1][0] = put_vp8_epel8_v4_altivec;
c->put_vp8_epel_pixels_tab[1][2][2] = put_vp8_epel8_h6v6_altivec;
c->put_vp8_epel_pixels_tab[1][1][1] = put_vp8_epel8_h4v4_altivec;
c->put_vp8_epel_pixels_tab[1][1][2] = put_vp8_epel8_h6v4_altivec;
c->put_vp8_epel_pixels_tab[1][2][1] = put_vp8_epel8_h4v6_altivec;
c->put_vp8_epel_pixels_tab[2][0][2] = put_vp8_epel4_h6_altivec;
c->put_vp8_epel_pixels_tab[2][2][0] = put_vp8_epel4_v6_altivec;
c->put_vp8_epel_pixels_tab[2][0][1] = put_vp8_epel4_h4_altivec;
c->put_vp8_epel_pixels_tab[2][1][0] = put_vp8_epel4_v4_altivec;
c->put_vp8_epel_pixels_tab[2][2][2] = put_vp8_epel4_h6v6_altivec;
c->put_vp8_epel_pixels_tab[2][1][1] = put_vp8_epel4_h4v4_altivec;
c->put_vp8_epel_pixels_tab[2][1][2] = put_vp8_epel4_h6v4_altivec;
c->put_vp8_epel_pixels_tab[2][2][1] = put_vp8_epel4_h4v6_altivec;
#endif /* HAVE_ALTIVEC */
}