From e0e46cae377347cbe1cd27c0d85568921b12c2ad Mon Sep 17 00:00:00 2001 From: Mans Rullgard Date: Mon, 21 Feb 2011 15:47:27 +0000 Subject: [PATCH] vp8: ppc: fix invalid reads in altivec epel mc The 4-tap filters should only access one row/column before the reference block. Signed-off-by: Mans Rullgard --- libavcodec/ppc/vp8dsp_altivec.c | 21 ++++++++++++++------- 1 file changed, 14 insertions(+), 7 deletions(-) diff --git a/libavcodec/ppc/vp8dsp_altivec.c b/libavcodec/ppc/vp8dsp_altivec.c index 8096c4a..8bb60aa 100644 --- a/libavcodec/ppc/vp8dsp_altivec.c +++ b/libavcodec/ppc/vp8dsp_altivec.c @@ -56,8 +56,8 @@ static const vec_s8 h_subpel_filters_outer[3] = vec_s8 filter_outerl = vec_sld(filter_outerh, filter_outerh, 2) #define FILTER_H(dstv, off) \ - a = vec_ld((off)-2, src); \ - b = vec_ld((off)-2+15, src); \ + a = vec_ld((off)-is6tap-1, src); \ + b = vec_ld((off)-is6tap-1+15, src); \ \ pixh = vec_perm(a, b, permh##off); \ pixl = vec_perm(a, b, perml##off); \ @@ -86,13 +86,15 @@ void put_vp8_epel_h_altivec_core(uint8_t *dst, int dst_stride, vec_s16 f16h, f16l; vec_s32 filth, filtl; - vec_u8 perm_inner = { 1,2,3,4, 2,3,4,5, 3,4,5,6, 4,5,6,7 }; + 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); - align_vec0 = vec_lvsl( -2, src); - align_vec8 = vec_lvsl(8-2, src); + 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); @@ -239,8 +241,13 @@ void put_vp8_epel ## WIDTH ## _v ## TAPS ## _altivec(uint8_t *dst, int dst_strid static void put_vp8_epel ## WIDTH ## _h ## HTAPS ## v ## VTAPS ## _altivec(uint8_t *dst, int stride, uint8_t *src, int s, int h, int mx, int my) \ { \ DECLARE_ALIGNED(16, uint8_t, tmp)[(2*WIDTH+5)*16]; \ - put_vp8_epel ## WIDTH ## _h ## HTAPS ## _altivec(tmp, 16, src-2*stride, stride, h+5, mx, my); \ - put_vp8_epel ## WIDTH ## _v ## VTAPS ## _altivec(dst, stride, tmp+2*16, 16, h, mx, my); \ + if (VTAPS == 6) { \ + put_vp8_epel ## WIDTH ## _h ## HTAPS ## _altivec(tmp, 16, src-2*stride, stride, h+5, mx, my); \ + put_vp8_epel ## WIDTH ## _v ## VTAPS ## _altivec(dst, stride, tmp+2*16, 16, h, mx, my); \ + } else { \ + put_vp8_epel ## WIDTH ## _h ## HTAPS ## _altivec(tmp, 16, src-stride, stride, h+4, mx, my); \ + put_vp8_epel ## WIDTH ## _v ## VTAPS ## _altivec(dst, stride, tmp+16, 16, h, mx, my); \ + } \ } EPEL_FUNCS(16,6) -- 2.7.4