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Diffstat (limited to 'contrib/ffmpeg/libavcodec/cabac.h')
-rw-r--r--contrib/ffmpeg/libavcodec/cabac.h859
1 files changed, 859 insertions, 0 deletions
diff --git a/contrib/ffmpeg/libavcodec/cabac.h b/contrib/ffmpeg/libavcodec/cabac.h
new file mode 100644
index 000000000..147d25ffa
--- /dev/null
+++ b/contrib/ffmpeg/libavcodec/cabac.h
@@ -0,0 +1,859 @@
+/*
+ * H.26L/H.264/AVC/JVT/14496-10/... encoder/decoder
+ * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
+ *
+ * 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
+ *
+ */
+
+/**
+ * @file cabac.h
+ * Context Adaptive Binary Arithmetic Coder.
+ */
+
+
+//#undef NDEBUG
+#include <assert.h>
+#ifdef ARCH_X86
+#include "x86_cpu.h"
+#endif
+
+#define CABAC_BITS 16
+#define CABAC_MASK ((1<<CABAC_BITS)-1)
+#define BRANCHLESS_CABAC_DECODER 1
+//#define ARCH_X86_DISABLED 1
+
+typedef struct CABACContext{
+ int low;
+ int range;
+ int outstanding_count;
+#ifdef STRICT_LIMITS
+ int symCount;
+#endif
+ const uint8_t *bytestream_start;
+ const uint8_t *bytestream;
+ const uint8_t *bytestream_end;
+ PutBitContext pb;
+}CABACContext;
+
+extern uint8_t ff_h264_mlps_state[4*64];
+extern uint8_t ff_h264_lps_range[4*2*64]; ///< rangeTabLPS
+extern uint8_t ff_h264_mps_state[2*64]; ///< transIdxMPS
+extern uint8_t ff_h264_lps_state[2*64]; ///< transIdxLPS
+extern const uint8_t ff_h264_norm_shift[512];
+
+
+void ff_init_cabac_encoder(CABACContext *c, uint8_t *buf, int buf_size);
+void ff_init_cabac_decoder(CABACContext *c, const uint8_t *buf, int buf_size);
+void ff_init_cabac_states(CABACContext *c);
+
+
+static inline void put_cabac_bit(CABACContext *c, int b){
+ put_bits(&c->pb, 1, b);
+ for(;c->outstanding_count; c->outstanding_count--){
+ put_bits(&c->pb, 1, 1-b);
+ }
+}
+
+static inline void renorm_cabac_encoder(CABACContext *c){
+ while(c->range < 0x100){
+ //FIXME optimize
+ if(c->low<0x100){
+ put_cabac_bit(c, 0);
+ }else if(c->low<0x200){
+ c->outstanding_count++;
+ c->low -= 0x100;
+ }else{
+ put_cabac_bit(c, 1);
+ c->low -= 0x200;
+ }
+
+ c->range+= c->range;
+ c->low += c->low;
+ }
+}
+
+static void put_cabac(CABACContext *c, uint8_t * const state, int bit){
+ int RangeLPS= ff_h264_lps_range[2*(c->range&0xC0) + *state];
+
+ if(bit == ((*state)&1)){
+ c->range -= RangeLPS;
+ *state= ff_h264_mps_state[*state];
+ }else{
+ c->low += c->range - RangeLPS;
+ c->range = RangeLPS;
+ *state= ff_h264_lps_state[*state];
+ }
+
+ renorm_cabac_encoder(c);
+
+#ifdef STRICT_LIMITS
+ c->symCount++;
+#endif
+}
+
+static void put_cabac_static(CABACContext *c, int RangeLPS, int bit){
+ assert(c->range > RangeLPS);
+
+ if(!bit){
+ c->range -= RangeLPS;
+ }else{
+ c->low += c->range - RangeLPS;
+ c->range = RangeLPS;
+ }
+
+ renorm_cabac_encoder(c);
+
+#ifdef STRICT_LIMITS
+ c->symCount++;
+#endif
+}
+
+/**
+ * @param bit 0 -> write zero bit, !=0 write one bit
+ */
+static void put_cabac_bypass(CABACContext *c, int bit){
+ c->low += c->low;
+
+ if(bit){
+ c->low += c->range;
+ }
+//FIXME optimize
+ if(c->low<0x200){
+ put_cabac_bit(c, 0);
+ }else if(c->low<0x400){
+ c->outstanding_count++;
+ c->low -= 0x200;
+ }else{
+ put_cabac_bit(c, 1);
+ c->low -= 0x400;
+ }
+
+#ifdef STRICT_LIMITS
+ c->symCount++;
+#endif
+}
+
+/**
+ *
+ * @return the number of bytes written
+ */
+static int put_cabac_terminate(CABACContext *c, int bit){
+ c->range -= 2;
+
+ if(!bit){
+ renorm_cabac_encoder(c);
+ }else{
+ c->low += c->range;
+ c->range= 2;
+
+ renorm_cabac_encoder(c);
+
+ assert(c->low <= 0x1FF);
+ put_cabac_bit(c, c->low>>9);
+ put_bits(&c->pb, 2, ((c->low>>7)&3)|1);
+
+ flush_put_bits(&c->pb); //FIXME FIXME FIXME XXX wrong
+ }
+
+#ifdef STRICT_LIMITS
+ c->symCount++;
+#endif
+
+ return (put_bits_count(&c->pb)+7)>>3;
+}
+
+/**
+ * put (truncated) unary binarization.
+ */
+static void put_cabac_u(CABACContext *c, uint8_t * state, int v, int max, int max_index, int truncated){
+ int i;
+
+ assert(v <= max);
+
+#if 1
+ for(i=0; i<v; i++){
+ put_cabac(c, state, 1);
+ if(i < max_index) state++;
+ }
+ if(truncated==0 || v<max)
+ put_cabac(c, state, 0);
+#else
+ if(v <= max_index){
+ for(i=0; i<v; i++){
+ put_cabac(c, state+i, 1);
+ }
+ if(truncated==0 || v<max)
+ put_cabac(c, state+i, 0);
+ }else{
+ for(i=0; i<=max_index; i++){
+ put_cabac(c, state+i, 1);
+ }
+ for(; i<v; i++){
+ put_cabac(c, state+max_index, 1);
+ }
+ if(truncated==0 || v<max)
+ put_cabac(c, state+max_index, 0);
+ }
+#endif
+}
+
+/**
+ * put unary exp golomb k-th order binarization.
+ */
+static void put_cabac_ueg(CABACContext *c, uint8_t * state, int v, int max, int is_signed, int k, int max_index){
+ int i;
+
+ if(v==0)
+ put_cabac(c, state, 0);
+ else{
+ const int sign= v < 0;
+
+ if(is_signed) v= FFABS(v);
+
+ if(v<max){
+ for(i=0; i<v; i++){
+ put_cabac(c, state, 1);
+ if(i < max_index) state++;
+ }
+
+ put_cabac(c, state, 0);
+ }else{
+ int m= 1<<k;
+
+ for(i=0; i<max; i++){
+ put_cabac(c, state, 1);
+ if(i < max_index) state++;
+ }
+
+ v -= max;
+ while(v >= m){ //FIXME optimize
+ put_cabac_bypass(c, 1);
+ v-= m;
+ m+= m;
+ }
+ put_cabac_bypass(c, 0);
+ while(m>>=1){
+ put_cabac_bypass(c, v&m);
+ }
+ }
+
+ if(is_signed)
+ put_cabac_bypass(c, sign);
+ }
+}
+
+static void refill(CABACContext *c){
+#if CABAC_BITS == 16
+ c->low+= (c->bytestream[0]<<9) + (c->bytestream[1]<<1);
+#else
+ c->low+= c->bytestream[0]<<1;
+#endif
+ c->low -= CABAC_MASK;
+ c->bytestream+= CABAC_BITS/8;
+}
+
+static void refill2(CABACContext *c){
+ int i, x;
+
+ x= c->low ^ (c->low-1);
+ i= 7 - ff_h264_norm_shift[x>>(CABAC_BITS-1)];
+
+ x= -CABAC_MASK;
+
+#if CABAC_BITS == 16
+ x+= (c->bytestream[0]<<9) + (c->bytestream[1]<<1);
+#else
+ x+= c->bytestream[0]<<1;
+#endif
+
+ c->low += x<<i;
+ c->bytestream+= CABAC_BITS/8;
+}
+
+static inline void renorm_cabac_decoder(CABACContext *c){
+ while(c->range < 0x100){
+ c->range+= c->range;
+ c->low+= c->low;
+ if(!(c->low & CABAC_MASK))
+ refill(c);
+ }
+}
+
+static inline void renorm_cabac_decoder_once(CABACContext *c){
+#ifdef ARCH_X86_DISABLED
+ int temp;
+#if 0
+ //P3:683 athlon:475
+ asm(
+ "lea -0x100(%0), %2 \n\t"
+ "shr $31, %2 \n\t" //FIXME 31->63 for x86-64
+ "shl %%cl, %0 \n\t"
+ "shl %%cl, %1 \n\t"
+ : "+r"(c->range), "+r"(c->low), "+c"(temp)
+ );
+#elif 0
+ //P3:680 athlon:474
+ asm(
+ "cmp $0x100, %0 \n\t"
+ "setb %%cl \n\t" //FIXME 31->63 for x86-64
+ "shl %%cl, %0 \n\t"
+ "shl %%cl, %1 \n\t"
+ : "+r"(c->range), "+r"(c->low), "+c"(temp)
+ );
+#elif 1
+ int temp2;
+ //P3:665 athlon:517
+ asm(
+ "lea -0x100(%0), %%eax \n\t"
+ "cdq \n\t"
+ "mov %0, %%eax \n\t"
+ "and %%edx, %0 \n\t"
+ "and %1, %%edx \n\t"
+ "add %%eax, %0 \n\t"
+ "add %%edx, %1 \n\t"
+ : "+r"(c->range), "+r"(c->low), "+a"(temp), "+d"(temp2)
+ );
+#elif 0
+ int temp2;
+ //P3:673 athlon:509
+ asm(
+ "cmp $0x100, %0 \n\t"
+ "sbb %%edx, %%edx \n\t"
+ "mov %0, %%eax \n\t"
+ "and %%edx, %0 \n\t"
+ "and %1, %%edx \n\t"
+ "add %%eax, %0 \n\t"
+ "add %%edx, %1 \n\t"
+ : "+r"(c->range), "+r"(c->low), "+a"(temp), "+d"(temp2)
+ );
+#else
+ int temp2;
+ //P3:677 athlon:511
+ asm(
+ "cmp $0x100, %0 \n\t"
+ "lea (%0, %0), %%eax \n\t"
+ "lea (%1, %1), %%edx \n\t"
+ "cmovb %%eax, %0 \n\t"
+ "cmovb %%edx, %1 \n\t"
+ : "+r"(c->range), "+r"(c->low), "+a"(temp), "+d"(temp2)
+ );
+#endif
+#else
+ //P3:675 athlon:476
+ int shift= (uint32_t)(c->range - 0x100)>>31;
+ c->range<<= shift;
+ c->low <<= shift;
+#endif
+ if(!(c->low & CABAC_MASK))
+ refill(c);
+}
+
+static int av_always_inline get_cabac_inline(CABACContext *c, uint8_t * const state){
+ //FIXME gcc generates duplicate load/stores for c->low and c->range
+#define LOW "0"
+#define RANGE "4"
+#ifdef ARCH_X86_64
+#define BYTESTART "16"
+#define BYTE "24"
+#define BYTEEND "32"
+#else
+#define BYTESTART "12"
+#define BYTE "16"
+#define BYTEEND "20"
+#endif
+#if defined(ARCH_X86) && defined(CONFIG_7REGS) && defined(CONFIG_EBX_AVAILABLE) && !( defined(ARCH_X86_64) && defined(PIC) )
+ int bit;
+
+#ifndef BRANCHLESS_CABAC_DECODER
+ asm volatile(
+ "movzbl (%1), %0 \n\t"
+ "movl "RANGE "(%2), %%ebx \n\t"
+ "movl "RANGE "(%2), %%edx \n\t"
+ "andl $0xC0, %%ebx \n\t"
+ "movzbl "MANGLE(ff_h264_lps_range)"(%0, %%ebx, 2), %%esi\n\t"
+ "movl "LOW "(%2), %%ebx \n\t"
+//eax:state ebx:low, edx:range, esi:RangeLPS
+ "subl %%esi, %%edx \n\t"
+ "movl %%edx, %%ecx \n\t"
+ "shll $17, %%ecx \n\t"
+ "cmpl %%ecx, %%ebx \n\t"
+ " ja 1f \n\t"
+
+#if 1
+ //athlon:4067 P3:4110
+ "lea -0x100(%%edx), %%ecx \n\t"
+ "shr $31, %%ecx \n\t"
+ "shl %%cl, %%edx \n\t"
+ "shl %%cl, %%ebx \n\t"
+#else
+ //athlon:4057 P3:4130
+ "cmp $0x100, %%edx \n\t" //FIXME avoidable
+ "setb %%cl \n\t"
+ "shl %%cl, %%edx \n\t"
+ "shl %%cl, %%ebx \n\t"
+#endif
+ "movzbl "MANGLE(ff_h264_mps_state)"(%0), %%ecx \n\t"
+ "movb %%cl, (%1) \n\t"
+//eax:state ebx:low, edx:range, esi:RangeLPS
+ "test %%bx, %%bx \n\t"
+ " jnz 2f \n\t"
+ "mov "BYTE "(%2), %%"REG_S" \n\t"
+ "subl $0xFFFF, %%ebx \n\t"
+ "movzwl (%%"REG_S"), %%ecx \n\t"
+ "bswap %%ecx \n\t"
+ "shrl $15, %%ecx \n\t"
+ "add $2, %%"REG_S" \n\t"
+ "addl %%ecx, %%ebx \n\t"
+ "mov %%"REG_S", "BYTE "(%2) \n\t"
+ "jmp 2f \n\t"
+ "1: \n\t"
+//eax:state ebx:low, edx:range, esi:RangeLPS
+ "subl %%ecx, %%ebx \n\t"
+ "movl %%esi, %%edx \n\t"
+ "movzbl " MANGLE(ff_h264_norm_shift) "(%%esi), %%ecx \n\t"
+ "shll %%cl, %%ebx \n\t"
+ "shll %%cl, %%edx \n\t"
+ "movzbl "MANGLE(ff_h264_lps_state)"(%0), %%ecx \n\t"
+ "movb %%cl, (%1) \n\t"
+ "add $1, %0 \n\t"
+ "test %%bx, %%bx \n\t"
+ " jnz 2f \n\t"
+
+ "mov "BYTE "(%2), %%"REG_c" \n\t"
+ "movzwl (%%"REG_c"), %%esi \n\t"
+ "bswap %%esi \n\t"
+ "shrl $15, %%esi \n\t"
+ "subl $0xFFFF, %%esi \n\t"
+ "add $2, %%"REG_c" \n\t"
+ "mov %%"REG_c", "BYTE "(%2) \n\t"
+
+ "leal -1(%%ebx), %%ecx \n\t"
+ "xorl %%ebx, %%ecx \n\t"
+ "shrl $15, %%ecx \n\t"
+ "movzbl " MANGLE(ff_h264_norm_shift) "(%%ecx), %%ecx \n\t"
+ "neg %%ecx \n\t"
+ "add $7, %%ecx \n\t"
+
+ "shll %%cl , %%esi \n\t"
+ "addl %%esi, %%ebx \n\t"
+ "2: \n\t"
+ "movl %%edx, "RANGE "(%2) \n\t"
+ "movl %%ebx, "LOW "(%2) \n\t"
+ :"=&a"(bit) //FIXME this is fragile gcc either runs out of registers or misscompiles it (for example if "+a"(bit) or "+m"(*state) is used
+ :"r"(state), "r"(c)
+ : "%"REG_c, "%ebx", "%edx", "%"REG_S, "memory"
+ );
+ bit&=1;
+#else /* BRANCHLESS_CABAC_DECODER */
+
+
+#if defined HAVE_FAST_CMOV
+#define BRANCHLESS_GET_CABAC_UPDATE(ret, cabac, statep, low, lowword, range, tmp, tmpbyte)\
+ "mov "tmp" , %%ecx \n\t"\
+ "shl $17 , "tmp" \n\t"\
+ "cmp "low" , "tmp" \n\t"\
+ "cmova %%ecx , "range" \n\t"\
+ "sbb %%ecx , %%ecx \n\t"\
+ "and %%ecx , "tmp" \n\t"\
+ "sub "tmp" , "low" \n\t"\
+ "xor %%ecx , "ret" \n\t"
+#else /* HAVE_FAST_CMOV */
+#define BRANCHLESS_GET_CABAC_UPDATE(ret, cabac, statep, low, lowword, range, tmp, tmpbyte)\
+ "mov "tmp" , %%ecx \n\t"\
+ "shl $17 , "tmp" \n\t"\
+ "sub "low" , "tmp" \n\t"\
+ "sar $31 , "tmp" \n\t" /*lps_mask*/\
+ "sub %%ecx , "range" \n\t" /*RangeLPS - range*/\
+ "and "tmp" , "range" \n\t" /*(RangeLPS - range)&lps_mask*/\
+ "add %%ecx , "range" \n\t" /*new range*/\
+ "shl $17 , %%ecx \n\t"\
+ "and "tmp" , %%ecx \n\t"\
+ "sub %%ecx , "low" \n\t"\
+ "xor "tmp" , "ret" \n\t"
+#endif /* HAVE_FAST_CMOV */
+
+
+#define BRANCHLESS_GET_CABAC(ret, cabac, statep, low, lowword, range, tmp, tmpbyte)\
+ "movzbl "statep" , "ret" \n\t"\
+ "mov "range" , "tmp" \n\t"\
+ "and $0xC0 , "range" \n\t"\
+ "movzbl "MANGLE(ff_h264_lps_range)"("ret", "range", 2), "range" \n\t"\
+ "sub "range" , "tmp" \n\t"\
+ BRANCHLESS_GET_CABAC_UPDATE(ret, cabac, statep, low, lowword, range, tmp, tmpbyte)\
+ "movzbl " MANGLE(ff_h264_norm_shift) "("range"), %%ecx \n\t"\
+ "shl %%cl , "range" \n\t"\
+ "movzbl "MANGLE(ff_h264_mlps_state)"+128("ret"), "tmp" \n\t"\
+ "mov "tmpbyte" , "statep" \n\t"\
+ "shl %%cl , "low" \n\t"\
+ "test "lowword" , "lowword" \n\t"\
+ " jnz 1f \n\t"\
+ "mov "BYTE"("cabac"), %%"REG_c" \n\t"\
+ "movzwl (%%"REG_c") , "tmp" \n\t"\
+ "bswap "tmp" \n\t"\
+ "shr $15 , "tmp" \n\t"\
+ "sub $0xFFFF , "tmp" \n\t"\
+ "add $2 , %%"REG_c" \n\t"\
+ "mov %%"REG_c" , "BYTE "("cabac") \n\t"\
+ "lea -1("low") , %%ecx \n\t"\
+ "xor "low" , %%ecx \n\t"\
+ "shr $15 , %%ecx \n\t"\
+ "movzbl " MANGLE(ff_h264_norm_shift) "(%%ecx), %%ecx \n\t"\
+ "neg %%ecx \n\t"\
+ "add $7 , %%ecx \n\t"\
+ "shl %%cl , "tmp" \n\t"\
+ "add "tmp" , "low" \n\t"\
+ "1: \n\t"
+
+ asm volatile(
+ "movl "RANGE "(%2), %%esi \n\t"
+ "movl "LOW "(%2), %%ebx \n\t"
+ BRANCHLESS_GET_CABAC("%0", "%2", "(%1)", "%%ebx", "%%bx", "%%esi", "%%edx", "%%dl")
+ "movl %%esi, "RANGE "(%2) \n\t"
+ "movl %%ebx, "LOW "(%2) \n\t"
+
+ :"=&a"(bit)
+ :"r"(state), "r"(c)
+ : "%"REG_c, "%ebx", "%edx", "%esi", "memory"
+ );
+ bit&=1;
+#endif /* BRANCHLESS_CABAC_DECODER */
+#else /* defined(ARCH_X86) && !(defined(PIC) && defined(__GNUC__)) */
+ int s = *state;
+ int RangeLPS= ff_h264_lps_range[2*(c->range&0xC0) + s];
+ int bit, lps_mask attribute_unused;
+
+ c->range -= RangeLPS;
+#ifndef BRANCHLESS_CABAC_DECODER
+ if(c->low < (c->range<<(CABAC_BITS+1))){
+ bit= s&1;
+ *state= ff_h264_mps_state[s];
+ renorm_cabac_decoder_once(c);
+ }else{
+ bit= ff_h264_norm_shift[RangeLPS];
+ c->low -= (c->range<<(CABAC_BITS+1));
+ *state= ff_h264_lps_state[s];
+ c->range = RangeLPS<<bit;
+ c->low <<= bit;
+ bit= (s&1)^1;
+
+ if(!(c->low & CABAC_MASK)){
+ refill2(c);
+ }
+ }
+#else /* BRANCHLESS_CABAC_DECODER */
+ lps_mask= ((c->range<<(CABAC_BITS+1)) - c->low)>>31;
+
+ c->low -= (c->range<<(CABAC_BITS+1)) & lps_mask;
+ c->range += (RangeLPS - c->range) & lps_mask;
+
+ s^=lps_mask;
+ *state= (ff_h264_mlps_state+128)[s];
+ bit= s&1;
+
+ lps_mask= ff_h264_norm_shift[c->range];
+ c->range<<= lps_mask;
+ c->low <<= lps_mask;
+ if(!(c->low & CABAC_MASK))
+ refill2(c);
+#endif /* BRANCHLESS_CABAC_DECODER */
+#endif /* defined(ARCH_X86) && !(defined(PIC) && defined(__GNUC__)) */
+ return bit;
+}
+
+static int av_noinline get_cabac_noinline(CABACContext *c, uint8_t * const state){
+ return get_cabac_inline(c,state);
+}
+
+static int get_cabac(CABACContext *c, uint8_t * const state){
+ return get_cabac_inline(c,state);
+}
+
+static int get_cabac_bypass(CABACContext *c){
+#if 0 //not faster
+ int bit;
+ asm volatile(
+ "movl "RANGE "(%1), %%ebx \n\t"
+ "movl "LOW "(%1), %%eax \n\t"
+ "shl $17, %%ebx \n\t"
+ "add %%eax, %%eax \n\t"
+ "sub %%ebx, %%eax \n\t"
+ "cdq \n\t"
+ "and %%edx, %%ebx \n\t"
+ "add %%ebx, %%eax \n\t"
+ "test %%ax, %%ax \n\t"
+ " jnz 1f \n\t"
+ "movl "BYTE "(%1), %%"REG_b" \n\t"
+ "subl $0xFFFF, %%eax \n\t"
+ "movzwl (%%"REG_b"), %%ecx \n\t"
+ "bswap %%ecx \n\t"
+ "shrl $15, %%ecx \n\t"
+ "addl $2, %%"REG_b" \n\t"
+ "addl %%ecx, %%eax \n\t"
+ "movl %%"REG_b", "BYTE "(%1) \n\t"
+ "1: \n\t"
+ "movl %%eax, "LOW "(%1) \n\t"
+
+ :"=&d"(bit)
+ :"r"(c)
+ : "%eax", "%"REG_b, "%ecx", "memory"
+ );
+ return bit+1;
+#else
+ int range;
+ c->low += c->low;
+
+ if(!(c->low & CABAC_MASK))
+ refill(c);
+
+ range= c->range<<(CABAC_BITS+1);
+ if(c->low < range){
+ return 0;
+ }else{
+ c->low -= range;
+ return 1;
+ }
+#endif
+}
+
+
+static av_always_inline int get_cabac_bypass_sign(CABACContext *c, int val){
+#if defined(ARCH_X86) && !(defined(PIC) && defined(__GNUC__))
+ asm volatile(
+ "movl "RANGE "(%1), %%ebx \n\t"
+ "movl "LOW "(%1), %%eax \n\t"
+ "shl $17, %%ebx \n\t"
+ "add %%eax, %%eax \n\t"
+ "sub %%ebx, %%eax \n\t"
+ "cdq \n\t"
+ "and %%edx, %%ebx \n\t"
+ "add %%ebx, %%eax \n\t"
+ "xor %%edx, %%ecx \n\t"
+ "sub %%edx, %%ecx \n\t"
+ "test %%ax, %%ax \n\t"
+ " jnz 1f \n\t"
+ "mov "BYTE "(%1), %%"REG_b" \n\t"
+ "subl $0xFFFF, %%eax \n\t"
+ "movzwl (%%"REG_b"), %%edx \n\t"
+ "bswap %%edx \n\t"
+ "shrl $15, %%edx \n\t"
+ "add $2, %%"REG_b" \n\t"
+ "addl %%edx, %%eax \n\t"
+ "mov %%"REG_b", "BYTE "(%1) \n\t"
+ "1: \n\t"
+ "movl %%eax, "LOW "(%1) \n\t"
+
+ :"+c"(val)
+ :"r"(c)
+ : "%eax", "%"REG_b, "%edx", "memory"
+ );
+ return val;
+#else
+ int range, mask;
+ c->low += c->low;
+
+ if(!(c->low & CABAC_MASK))
+ refill(c);
+
+ range= c->range<<(CABAC_BITS+1);
+ c->low -= range;
+ mask= c->low >> 31;
+ range &= mask;
+ c->low += range;
+ return (val^mask)-mask;
+#endif
+}
+
+//FIXME the x86 code from this file should be moved into i386/h264 or cabac something.c/h (note ill kill you if you move my code away from under my fingers before iam finished with it!)
+//FIXME use some macros to avoid duplicatin get_cabac (cant be done yet as that would make optimization work hard)
+#if defined(ARCH_X86) && defined(CONFIG_7REGS) && defined(CONFIG_EBX_AVAILABLE) && !( defined(ARCH_X86_64) && defined(PIC) )
+static int decode_significance_x86(CABACContext *c, int max_coeff, uint8_t *significant_coeff_ctx_base, int *index){
+ void *end= significant_coeff_ctx_base + max_coeff - 1;
+ int minusstart= -(int)significant_coeff_ctx_base;
+ int minusindex= 4-(int)index;
+ int coeff_count;
+ asm volatile(
+ "movl "RANGE "(%3), %%esi \n\t"
+ "movl "LOW "(%3), %%ebx \n\t"
+
+ "2: \n\t"
+
+ BRANCHLESS_GET_CABAC("%%edx", "%3", "(%1)", "%%ebx", "%%bx", "%%esi", "%%eax", "%%al")
+
+ "test $1, %%edx \n\t"
+ " jz 3f \n\t"
+
+ BRANCHLESS_GET_CABAC("%%edx", "%3", "61(%1)", "%%ebx", "%%bx", "%%esi", "%%eax", "%%al")
+
+ "mov %2, %%"REG_a" \n\t"
+ "movl %4, %%ecx \n\t"
+ "add %1, %%"REG_c" \n\t"
+ "movl %%ecx, (%%"REG_a") \n\t"
+
+ "test $1, %%edx \n\t"
+ " jnz 4f \n\t"
+
+ "add $4, %%"REG_a" \n\t"
+ "mov %%"REG_a", %2 \n\t"
+
+ "3: \n\t"
+ "add $1, %1 \n\t"
+ "cmp %5, %1 \n\t"
+ " jb 2b \n\t"
+ "mov %2, %%"REG_a" \n\t"
+ "movl %4, %%ecx \n\t"
+ "add %1, %%"REG_c" \n\t"
+ "movl %%ecx, (%%"REG_a") \n\t"
+ "4: \n\t"
+ "add %6, %%eax \n\t"
+ "shr $2, %%eax \n\t"
+
+ "movl %%esi, "RANGE "(%3) \n\t"
+ "movl %%ebx, "LOW "(%3) \n\t"
+ :"=&a"(coeff_count), "+r"(significant_coeff_ctx_base), "+m"(index)\
+ :"r"(c), "m"(minusstart), "m"(end), "m"(minusindex)\
+ : "%"REG_c, "%ebx", "%edx", "%esi", "memory"\
+ );
+ return coeff_count;
+}
+
+static int decode_significance_8x8_x86(CABACContext *c, uint8_t *significant_coeff_ctx_base, int *index, uint8_t *sig_off){
+ int minusindex= 4-(int)index;
+ int coeff_count;
+ long last=0;
+ asm volatile(
+ "movl "RANGE "(%3), %%esi \n\t"
+ "movl "LOW "(%3), %%ebx \n\t"
+
+ "mov %1, %%"REG_D" \n\t"
+ "2: \n\t"
+
+ "mov %6, %%"REG_a" \n\t"
+ "movzbl (%%"REG_a", %%"REG_D"), %%edi \n\t"
+ "add %5, %%"REG_D" \n\t"
+
+ BRANCHLESS_GET_CABAC("%%edx", "%3", "(%%"REG_D")", "%%ebx", "%%bx", "%%esi", "%%eax", "%%al")
+
+ "mov %1, %%edi \n\t"
+ "test $1, %%edx \n\t"
+ " jz 3f \n\t"
+
+ "movzbl "MANGLE(last_coeff_flag_offset_8x8)"(%%edi), %%edi\n\t"
+ "add %5, %%"REG_D" \n\t"
+
+ BRANCHLESS_GET_CABAC("%%edx", "%3", "15(%%"REG_D")", "%%ebx", "%%bx", "%%esi", "%%eax", "%%al")
+
+ "mov %2, %%"REG_a" \n\t"
+ "mov %1, %%edi \n\t"
+ "movl %%edi, (%%"REG_a") \n\t"
+
+ "test $1, %%edx \n\t"
+ " jnz 4f \n\t"
+
+ "add $4, %%"REG_a" \n\t"
+ "mov %%"REG_a", %2 \n\t"
+
+ "3: \n\t"
+ "addl $1, %%edi \n\t"
+ "mov %%edi, %1 \n\t"
+ "cmpl $63, %%edi \n\t"
+ " jb 2b \n\t"
+ "mov %2, %%"REG_a" \n\t"
+ "movl %%edi, (%%"REG_a") \n\t"
+ "4: \n\t"
+ "addl %4, %%eax \n\t"
+ "shr $2, %%eax \n\t"
+
+ "movl %%esi, "RANGE "(%3) \n\t"
+ "movl %%ebx, "LOW "(%3) \n\t"
+ :"=&a"(coeff_count),"+m"(last), "+m"(index)\
+ :"r"(c), "m"(minusindex), "m"(significant_coeff_ctx_base), "m"(sig_off)\
+ : "%"REG_c, "%ebx", "%edx", "%esi", "%"REG_D, "memory"\
+ );
+ return coeff_count;
+}
+#endif /* defined(ARCH_X86) && !(defined(PIC) && defined(__GNUC__)) */
+
+/**
+ *
+ * @return the number of bytes read or 0 if no end
+ */
+static int get_cabac_terminate(CABACContext *c){
+ c->range -= 2;
+ if(c->low < c->range<<(CABAC_BITS+1)){
+ renorm_cabac_decoder_once(c);
+ return 0;
+ }else{
+ return c->bytestream - c->bytestream_start;
+ }
+}
+
+/**
+ * get (truncated) unnary binarization.
+ */
+static int get_cabac_u(CABACContext *c, uint8_t * state, int max, int max_index, int truncated){
+ int i;
+
+ for(i=0; i<max; i++){
+ if(get_cabac(c, state)==0)
+ return i;
+
+ if(i< max_index) state++;
+ }
+
+ return truncated ? max : -1;
+}
+
+/**
+ * get unary exp golomb k-th order binarization.
+ */
+static int get_cabac_ueg(CABACContext *c, uint8_t * state, int max, int is_signed, int k, int max_index){
+ int i, v;
+ int m= 1<<k;
+
+ if(get_cabac(c, state)==0)
+ return 0;
+
+ if(0 < max_index) state++;
+
+ for(i=1; i<max; i++){
+ if(get_cabac(c, state)==0){
+ if(is_signed && get_cabac_bypass(c)){
+ return -i;
+ }else
+ return i;
+ }
+
+ if(i < max_index) state++;
+ }
+
+ while(get_cabac_bypass(c)){
+ i+= m;
+ m+= m;
+ }
+
+ v=0;
+ while(m>>=1){
+ v+= v + get_cabac_bypass(c);
+ }
+ i += v;
+
+ if(is_signed && get_cabac_bypass(c)){
+ return -i;
+ }else
+ return i;
+}
generated by cgit v1.2.3 (git 2.25.1) at 2025-04-26 18:39:57 +0000