1
0
mirror of https://github.com/FFmpeg/FFmpeg.git synced 2024-12-23 12:43:46 +02:00

avcodec/ppc/h264dsp: POWER LE support in h264_idct_dc_add_internal() fix vec_lvsl bug

We got defective video when use GCC 4.9.2 instead of GCC 4.9.1 to compile FFMEPG. And further found
that GCC 4.8 and 4.9 need patch to fix the lvsl/lvsr bug on POWER LE, and GCC 5.1 contains
the correct code since its release. The message on gcc-patches requesting approval for lvsl/lvsr
patch is at https://gcc.gnu.org/ml/gcc-patches/2014-10/msg00228.html.

The fixed code avoids using lvsl and will not depends on GCC version, also it uses less instructions on POWER LE.

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
This commit is contained in:
Rong Yan 2015-05-14 06:43:44 +00:00 committed by Michael Niedermayer
parent 8252f63d1b
commit a2cd07d22a

View File

@ -256,6 +256,11 @@ static void h264_idct8_add_altivec(uint8_t *dst, int16_t *dct, int stride)
ALTIVEC_STORE_SUM_CLIP(&dst[7*stride], idct7, perm_ldv, perm_stv, sel);
}
#if HAVE_BIGENDIAN
#define DST_LD vec_ld
#else
#define DST_LD vec_vsx_ld
#endif
static av_always_inline void h264_idct_dc_add_internal(uint8_t *dst, int16_t *block, int stride, int size)
{
vec_s16 dc16;
@ -275,18 +280,17 @@ static av_always_inline void h264_idct_dc_add_internal(uint8_t *dst, int16_t *bl
dcplus = vec_packsu(dc16, zero_s16v);
dcminus = vec_packsu(vec_sub(zero_s16v, dc16), zero_s16v);
#if HAVE_BIGENDIAN
aligner = vec_lvsr(0, dst);
#if !HAVE_BIGENDIAN
aligner = vec_perm(aligner, zero_u8v, vcswapc());
#endif
dcplus = vec_perm(dcplus, dcplus, aligner);
dcminus = vec_perm(dcminus, dcminus, aligner);
#endif
for (i = 0; i < size; i += 4) {
v0 = vec_ld(0, dst+0*stride);
v1 = vec_ld(0, dst+1*stride);
v2 = vec_ld(0, dst+2*stride);
v3 = vec_ld(0, dst+3*stride);
v0 = DST_LD(0, dst+0*stride);
v1 = DST_LD(0, dst+1*stride);
v2 = DST_LD(0, dst+2*stride);
v3 = DST_LD(0, dst+3*stride);
v0 = vec_adds(v0, dcplus);
v1 = vec_adds(v1, dcplus);
@ -298,10 +302,10 @@ static av_always_inline void h264_idct_dc_add_internal(uint8_t *dst, int16_t *bl
v2 = vec_subs(v2, dcminus);
v3 = vec_subs(v3, dcminus);
vec_st(v0, 0, dst+0*stride);
vec_st(v1, 0, dst+1*stride);
vec_st(v2, 0, dst+2*stride);
vec_st(v3, 0, dst+3*stride);
VEC_ST(v0, 0, dst+0*stride);
VEC_ST(v1, 0, dst+1*stride);
VEC_ST(v2, 0, dst+2*stride);
VEC_ST(v3, 0, dst+3*stride);
dst += 4*stride;
}