PR #20901 opened by Sean McGovern (sean_mcg) URL: https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/20901 Patch URL: https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/20901.patch
It fails sporadically on big- or little-endian POWER/PPC, as well as triggers the undefined-behaviour & address scanners in GCC. refs: #20832 >From 35464ad9ebe1f0502775748e680dc0167ddc57cc Mon Sep 17 00:00:00 2001 From: Sean McGovern <[email protected]> Date: Wed, 12 Nov 2025 14:22:44 -0500 Subject: [PATCH] libavcodec/ppc: remove broken AltiVec acceleration for lossless audio It fails sporadically on big- or little-endian POWER/PPC, as well as triggers the undefined-behaviour & address scanners in GCC. --- libavcodec/lossless_audiodsp.c | 2 - libavcodec/lossless_audiodsp.h | 1 - libavcodec/ppc/Makefile | 1 - libavcodec/ppc/lossless_audiodsp_altivec.c | 91 ---------------------- 4 files changed, 95 deletions(-) delete mode 100644 libavcodec/ppc/lossless_audiodsp_altivec.c diff --git a/libavcodec/lossless_audiodsp.c b/libavcodec/lossless_audiodsp.c index b0d64cf5b3..94e6ce0989 100644 --- a/libavcodec/lossless_audiodsp.c +++ b/libavcodec/lossless_audiodsp.c @@ -61,8 +61,6 @@ av_cold void ff_llauddsp_init(LLAudDSPContext *c) #if ARCH_ARM ff_llauddsp_init_arm(c); -#elif ARCH_PPC - ff_llauddsp_init_ppc(c); #elif ARCH_RISCV ff_llauddsp_init_riscv(c); #elif ARCH_X86 diff --git a/libavcodec/lossless_audiodsp.h b/libavcodec/lossless_audiodsp.h index cf2d43d7c9..e89e27fef0 100644 --- a/libavcodec/lossless_audiodsp.h +++ b/libavcodec/lossless_audiodsp.h @@ -45,7 +45,6 @@ typedef struct LLAudDSPContext { void ff_llauddsp_init(LLAudDSPContext *c); void ff_llauddsp_init_arm(LLAudDSPContext *c); -void ff_llauddsp_init_ppc(LLAudDSPContext *c); void ff_llauddsp_init_riscv(LLAudDSPContext *c); void ff_llauddsp_init_x86(LLAudDSPContext *c); diff --git a/libavcodec/ppc/Makefile b/libavcodec/ppc/Makefile index cbd9621e05..bddba27727 100644 --- a/libavcodec/ppc/Makefile +++ b/libavcodec/ppc/Makefile @@ -21,7 +21,6 @@ OBJS-$(CONFIG_VP8DSP) += ppc/vp8dsp_altivec.o # decoders/encoders OBJS-$(CONFIG_HEVC_DECODER) += ppc/hevcdsp.o -OBJS-$(CONFIG_LLAUDDSP) += ppc/lossless_audiodsp_altivec.o OBJS-$(CONFIG_MPEG4_DECODER) += ppc/mpeg4videodsp.o OBJS-$(CONFIG_SVQ1_ENCODER) += ppc/svq1enc_altivec.o OBJS-$(CONFIG_VORBIS_DECODER) += ppc/vorbisdsp_altivec.o diff --git a/libavcodec/ppc/lossless_audiodsp_altivec.c b/libavcodec/ppc/lossless_audiodsp_altivec.c deleted file mode 100644 index 298e6c38a0..0000000000 --- a/libavcodec/ppc/lossless_audiodsp_altivec.c +++ /dev/null @@ -1,91 +0,0 @@ -/* - * Copyright (c) 2007 Luca Barbato <[email protected]> - * - * 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/lossless_audiodsp.h" - -#if HAVE_BIGENDIAN -#define GET_T(tt0,tt1,src,a,b){ \ - a = vec_ld(16, src); \ - tt0 = vec_perm(b, a, align); \ - b = vec_ld(32, src); \ - tt1 = vec_perm(a, b, align); \ - } -#else -#define GET_T(tt0,tt1,src,a,b){ \ - tt0 = vec_vsx_ld(0, src); \ - tt1 = vec_vsx_ld(16, src); \ - } -#endif - -#if HAVE_ALTIVEC -static int32_t scalarproduct_and_madd_int16_altivec(int16_t *v1, - const int16_t *v2, - const int16_t *v3, - int order, int mul) -{ - LOAD_ZERO; - vec_s16 *pv1 = (vec_s16 *) v1; - register vec_s16 muls = { mul, mul, mul, mul, mul, mul, mul, mul }; - register vec_s16 t0, t1, i0, i1, i4, i2, i3; - register vec_s32 res = zero_s32v; -#if HAVE_BIGENDIAN - register vec_u8 align = vec_lvsl(0, v2); - i2 = vec_ld(0, v2); - i3 = vec_ld(0, v3); -#endif - int32_t ires; - - order >>= 4; - do { - GET_T(t0,t1,v2,i1,i2); - i0 = pv1[0]; - i1 = pv1[1]; - res = vec_msum(t0, i0, res); - res = vec_msum(t1, i1, res); - GET_T(t0,t1,v3,i4,i3); - pv1[0] = vec_mladd(t0, muls, i0); - pv1[1] = vec_mladd(t1, muls, i1); - pv1 += 2; - v2 += 16; - v3 += 16; - } while (--order); - res = vec_splat(vec_sums(res, zero_s32v), 3); - vec_ste(res, 0, &ires); - - return ires; -} -#endif /* HAVE_ALTIVEC */ - -av_cold void ff_llauddsp_init_ppc(LLAudDSPContext *c) -{ -#if HAVE_ALTIVEC - if (!PPC_ALTIVEC(av_get_cpu_flags())) - return; - - c->scalarproduct_and_madd_int16 = scalarproduct_and_madd_int16_altivec; -#endif /* HAVE_ALTIVEC */ -} -- 2.49.1 _______________________________________________ ffmpeg-devel mailing list -- [email protected] To unsubscribe send an email to [email protected]
