Files
dvdisaster/rs-encoder-sse2.c
2017-12-21 05:31:58 +11:00

113 lines
3.0 KiB
C

/* dvdisaster: Additional error correction for optical media.
* Copyright (C) 2004-2017 Carsten Gnoerlich.
*
* Email: carsten@dvdisaster.org -or- cgnoerlich@fsfe.org
* Project homepage: http://www.dvdisaster.org
*
* This file is part of dvdisaster.
*
* dvdisaster is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* dvdisaster 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with dvdisaster. If not, see <http://www.gnu.org/licenses/>.
*/
#include "dvdisaster.h"
#ifdef HAVE_SSE2
#include <emmintrin.h>
#ifdef HAVE_CPUID
#include <cpuid.h>
#else
#include "compat/cpuid.h"
#endif
#endif
/***
*** Reed-Solomon encoding using SSE2 intrinsics
***/
/* SSE 2 version */
#ifdef HAVE_SSE2
int ProbeSSE2(void)
{ unsigned int eax, ebx, ecx, edx;
if(!__get_cpuid(1, &eax, &ebx, &ecx, &edx))
{ Verbose("[ProbeSSE2: get_cpuid() failed]\n");
return 0;
}
if(edx & bit_SSE2)
{ Verbose("[ProbeSSE2: SSE2 available]\n");
return 1;
}
else
{ Verbose("[ProbeSSE2: no SSE2]\n");
return 0;
}
}
void encode_next_layer_sse2(ReedSolomonTables *rt, unsigned char *data, unsigned char *parity, guint64 layer_size, int shift)
{ gint32 *gf_index_of = rt->gfTables->indexOf;
gint32 *enc_alpha_to = rt->gfTables->encAlphaTo;
gint32 *rs_gpoly = rt->gpoly;
int nroots = rt->nroots;
int nroots_aligned = (nroots+15)&~15;
int nroots_full = nroots_aligned>>4;
int i,j;
for(i=0; i<layer_size; i++)
{ int feedback = gf_index_of[data[i] ^ parity[shift]];
int offset = nroots-shift-1;
if(feedback != GF_ALPHA0) /* non-zero feedback term */
{ guint8 *par_idx = (guint8*)parity;
guint8 *e_lut = rt->bLut[feedback]+offset;
__m128i par, lut, out;
/* Process lut in 128 bit steps */
for(j=nroots_full; j; j--)
{
par = _mm_load_si128((__m128i*)par_idx);
lut = _mm_loadu_si128((__m128i*)e_lut);
out = _mm_xor_si128(par, lut);
_mm_store_si128((__m128i*)par_idx, out);
par_idx += 16;
e_lut += 16;
}
parity[shift] = enc_alpha_to[feedback + rs_gpoly[0]];
}
else /* zero feedback term */
parity[shift] = 0;
parity += nroots_aligned;
}
}
#else /* don't have SSE2 */
/* Stub functions to keep the linker happy.
* Should never be executed.
*/
int ProbeSSE2()
{ return 0;
}
void encode_next_layer_sse2(ReedSolomonTables *rt, unsigned char *data, unsigned char *parity, guint64 layer_size, int shift)
{
Stop("Mega borkage - EncodeNextLayerSSE2() stub called.\n");
}
#endif /* HAVE_SSE2 */