* 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
+ * @file libavcodec/cabac.h
* Context Adaptive Binary Arithmetic Coder.
*/
+#ifndef AVCODEC_CABAC_H
+#define AVCODEC_CABAC_H
+
+#include "put_bits.h"
//#undef NDEBUG
#include <assert.h>
+#include "libavutil/x86_cpu.h"
#define CABAC_BITS 16
#define CABAC_MASK ((1<<CABAC_BITS)-1)
-#define BRANCHLESS_CABAD 1
+#define BRANCHLESS_CABAC_DECODER 1
+//#define ARCH_X86_DISABLED 1
typedef struct CABACContext{
int low;
#ifdef STRICT_LIMITS
int symCount;
#endif
- uint8_t lps_range[2*65][4]; ///< rangeTabLPS
- uint8_t lps_state[2*64]; ///< transIdxLPS
- uint8_t mps_state[2*64]; ///< transIdxMPS
const uint8_t *bytestream_start;
const uint8_t *bytestream;
const uint8_t *bytestream_end;
PutBitContext pb;
}CABACContext;
-extern const uint8_t ff_h264_lps_range[64][4];
-extern const uint8_t ff_h264_mps_state[64];
-extern const uint8_t ff_h264_lps_state[64];
-extern const uint8_t ff_h264_norm_shift[128];
+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, uint8_t const (*lps_range)[4],
- uint8_t const *mps_state, uint8_t const *lps_state, int state_count);
+void ff_init_cabac_states(CABACContext *c);
static inline void put_cabac_bit(CABACContext *c, int b){
}
}
+#ifdef TEST
static void put_cabac(CABACContext *c, uint8_t * const state, int bit){
- int RangeLPS= c->lps_range[*state][c->range>>6];
+ int RangeLPS= ff_h264_lps_range[2*(c->range&0xC0) + *state];
if(bit == ((*state)&1)){
c->range -= RangeLPS;
- *state= c->mps_state[*state];
+ *state= ff_h264_mps_state[*state];
}else{
c->low += c->range - RangeLPS;
c->range = RangeLPS;
- *state= c->lps_state[*state];
+ *state= ff_h264_lps_state[*state];
}
renorm_cabac_encoder(c);
else{
const int sign= v < 0;
- if(is_signed) v= ABS(v);
+ if(is_signed) v= FFABS(v);
if(v<max){
for(i=0; i<v; i++){
put_cabac_bypass(c, sign);
}
}
+#endif /* TEST */
static void refill(CABACContext *c){
#if CABAC_BITS == 16
c->bytestream+= CABAC_BITS/8;
}
+#if ! ( ARCH_X86 && HAVE_7REGS && HAVE_EBX_AVAILABLE && !defined(BROKEN_RELOCATIONS) )
static void refill2(CABACContext *c){
int i, x;
x= c->low ^ (c->low-1);
- i= 7 - ff_h264_norm_shift[x>>(CABAC_BITS+1)];
+ i= 7 - ff_h264_norm_shift[x>>(CABAC_BITS-1)];
x= -CABAC_MASK;
c->low += x<<i;
c->bytestream+= CABAC_BITS/8;
}
+#endif
static inline void renorm_cabac_decoder(CABACContext *c){
- while(c->range < (0x200 << CABAC_BITS)){
+ while(c->range < 0x100){
c->range+= c->range;
c->low+= c->low;
if(!(c->low & CABAC_MASK))
int temp;
#if 0
//P3:683 athlon:475
- asm(
- "lea -0x2000000(%0), %2 \n\t"
+ __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"
);
#elif 0
//P3:680 athlon:474
- asm(
- "cmp $0x2000000, %0 \n\t"
+ __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"
#elif 1
int temp2;
//P3:665 athlon:517
- asm(
- "lea -0x2000000(%0), %%eax \n\t"
- "cdq \n\t"
+ __asm__(
+ "lea -0x100(%0), %%eax \n\t"
+ "cltd \n\t"
"mov %0, %%eax \n\t"
"and %%edx, %0 \n\t"
"and %1, %%edx \n\t"
#elif 0
int temp2;
//P3:673 athlon:509
- asm(
- "cmp $0x2000000, %0 \n\t"
+ __asm__(
+ "cmp $0x100, %0 \n\t"
"sbb %%edx, %%edx \n\t"
"mov %0, %%eax \n\t"
"and %%edx, %0 \n\t"
#else
int temp2;
//P3:677 athlon:511
- asm(
- "cmp $0x2000000, %0 \n\t"
+ __asm__(
+ "cmp $0x100, %0 \n\t"
"lea (%0, %0), %%eax \n\t"
"lea (%1, %1), %%edx \n\t"
"cmovb %%eax, %0 \n\t"
#endif
#else
//P3:675 athlon:476
- int shift= (uint32_t)(c->range - (0x200 << CABAC_BITS))>>31;
+ int shift= (uint32_t)(c->range - 0x100)>>31;
c->range<<= shift;
c->low <<= shift;
#endif
refill(c);
}
-static int get_cabac(CABACContext *c, uint8_t * const state){
+static av_always_inline int get_cabac_inline(CABACContext *c, uint8_t * const state){
//FIXME gcc generates duplicate load/stores for c->low and c->range
-#ifdef ARCH_X86
- int bit;
-
#define LOW "0"
#define RANGE "4"
-#define LPS_RANGE "12"
-#define LPS_STATE "12+2*65*4"
-#define MPS_STATE "12+2*65*4+2*64"
-#define BYTESTART "12+2*65*4+4*64"
-#define BYTE "16+2*65*4+4*64"
-#define BYTEEND "20+2*65*4+4*64"
-#ifndef BRANCHLESS_CABAD
- asm volatile(
- "movzbl (%1), %%eax \n\t"
+#if ARCH_X86_64
+#define BYTESTART "16"
+#define BYTE "24"
+#define BYTEEND "32"
+#else
+#define BYTESTART "12"
+#define BYTE "16"
+#define BYTEEND "20"
+#endif
+#if ARCH_X86 && HAVE_7REGS && HAVE_EBX_AVAILABLE && !defined(BROKEN_RELOCATIONS)
+ 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"
- "shrl $23, %%ebx \n\t"
- "leal "LPS_RANGE"(%2, %%eax, 4), %%esi \n\t"
- "movzbl (%%ebx, %%esi), %%esi \n\t"
- "shll $17, %%esi \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"
- "cmpl %%edx, %%ebx \n\t"
+ "movl %%edx, %%ecx \n\t"
+ "shll $17, %%ecx \n\t"
+ "cmpl %%ecx, %%ebx \n\t"
" ja 1f \n\t"
- "cmp $0x2000000, %%edx \n\t" //FIXME avoidable
+
+#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"
- "movzbl "MPS_STATE"(%2, %%eax), %%ecx \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"
- "movl "BYTE "(%2), %%esi \n\t"
+ "mov "BYTE "(%2), %%"REG_S" \n\t"
"subl $0xFFFF, %%ebx \n\t"
- "movzwl (%%esi), %%ecx \n\t"
+ "movzwl (%%"REG_S"), %%ecx \n\t"
"bswap %%ecx \n\t"
"shrl $15, %%ecx \n\t"
- "addl $2, %%esi \n\t"
+ "add $2, %%"REG_S" \n\t"
"addl %%ecx, %%ebx \n\t"
- "movl %%esi, "BYTE "(%2) \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 %%edx, %%ebx \n\t"
+ "subl %%ecx, %%ebx \n\t"
"movl %%esi, %%edx \n\t"
- "shr $19, %%esi \n\t"
"movzbl " MANGLE(ff_h264_norm_shift) "(%%esi), %%ecx \n\t"
"shll %%cl, %%ebx \n\t"
"shll %%cl, %%edx \n\t"
- "movzbl "LPS_STATE"(%2, %%eax), %%ecx \n\t"
+ "movzbl "MANGLE(ff_h264_lps_state)"(%0), %%ecx \n\t"
"movb %%cl, (%1) \n\t"
- "addl $1, %%eax \n\t"
+ "add $1, %0 \n\t"
"test %%bx, %%bx \n\t"
" jnz 2f \n\t"
- "movl "BYTE "(%2), %%ecx \n\t"
- "movzwl (%%ecx), %%esi \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"
- "addl $2, %%ecx \n\t"
- "movl %%ecx, "BYTE "(%2) \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 $17, %%ecx \n\t"
+ "shrl $15, %%ecx \n\t"
"movzbl " MANGLE(ff_h264_norm_shift) "(%%ecx), %%ecx \n\t"
- "neg %%cl \n\t"
- "add $7, %%cl \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
+ :"=&a"(bit) //FIXME this is fragile gcc either runs out of registers or miscompiles it (for example if "+a"(bit) or "+m"(*state) is used
:"r"(state), "r"(c)
- : "%ecx", "%ebx", "%edx", "%esi"
+ : "%"REG_c, "%ebx", "%edx", "%"REG_S, "memory"
);
bit&=1;
-#else
- asm volatile(
- "movzbl (%1), %%eax \n\t"
- "movl "RANGE "(%2), %%ebx \n\t"
- "movl "RANGE "(%2), %%edx \n\t"
- "shrl $23, %%ebx \n\t"
- "leal "LPS_RANGE"(%2, %%eax, 4), %%esi \n\t"
- "movzbl (%%ebx, %%esi), %%esi \n\t"
- "shll $17, %%esi \n\t"
+#else /* BRANCHLESS_CABAC_DECODER */
+
+
+#if 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"
-//eax:state ebx:low, edx:range, esi:RangeLPS
- "subl %%esi, %%edx \n\t"
-#ifdef CMOV_IS_FAST //FIXME actually define this somewhere
- "cmpl %%ebx, %%edx \n\t"
- "cmova %%edx, %%esi \n\t"
- "sbbl %%ecx, %%ecx \n\t"
- "andl %%ecx, %%edx \n\t"
- "subl %%edx, %%ebx \n\t"
- "xorl %%ecx, %%eax \n\t"
-#else
- "movl %%edx, %%ecx \n\t"
- "subl %%ebx, %%edx \n\t"
- "sarl $31, %%edx \n\t" //lps_mask
- "subl %%ecx, %%esi \n\t" //RangeLPS - range
- "andl %%edx, %%esi \n\t" //(RangeLPS - range)&lps_mask
- "addl %%ecx, %%esi \n\t" //new range
- "andl %%edx, %%ecx \n\t"
- "subl %%ecx, %%ebx \n\t"
- "xorl %%edx, %%eax \n\t"
-#endif
-
-//eax:state ebx:low edx:mask esi:range
- "movzbl "MPS_STATE"(%2, %%eax), %%ecx \n\t"
- "movb %%cl, (%1) \n\t"
-
- "movl %%esi, %%edx \n\t"
-//eax:bit ebx:low edx:range esi:range
-
- "shr $19, %%esi \n\t"
- "movzbl " MANGLE(ff_h264_norm_shift) "(%%esi), %%ecx \n\t"
- "shll %%cl, %%ebx \n\t"
- "shll %%cl, %%edx \n\t"
- "test %%bx, %%bx \n\t"
- " jnz 1f \n\t"
-
- "movl "BYTE "(%2), %%ecx \n\t"
- "movzwl (%%ecx), %%esi \n\t"
- "bswap %%esi \n\t"
- "shrl $15, %%esi \n\t"
- "subl $0xFFFF, %%esi \n\t"
- "addl $2, %%ecx \n\t"
- "movl %%ecx, "BYTE "(%2) \n\t"
-
- "leal -1(%%ebx), %%ecx \n\t"
- "xorl %%ebx, %%ecx \n\t"
- "shrl $17, %%ecx \n\t"
- "movzbl " MANGLE(ff_h264_norm_shift) "(%%ecx), %%ecx \n\t"
- "neg %%cl \n\t"
- "add $7, %%cl \n\t"
-
- "shll %%cl , %%esi \n\t"
- "addl %%esi, %%ebx \n\t"
- "1: \n\t"
- "movl %%edx, "RANGE "(%2) \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)
- : "%ecx", "%ebx", "%edx", "%esi"
+ : "%"REG_c, "%ebx", "%edx", "%esi", "memory"
);
bit&=1;
-#endif
-#else
+#endif /* BRANCHLESS_CABAC_DECODER */
+#else /* ARCH_X86 && HAVE_7REGS && HAVE_EBX_AVAILABLE && !defined(BROKEN_RELOCATIONS) */
int s = *state;
- int RangeLPS= c->lps_range[s][c->range>>(CABAC_BITS+7)]<<(CABAC_BITS+1);
- int bit, lps_mask attribute_unused;
+ int RangeLPS= ff_h264_lps_range[2*(c->range&0xC0) + s];
+ int bit, lps_mask av_unused;
c->range -= RangeLPS;
-#ifndef BRANCHLESS_CABAD
- if(c->low < c->range){
+#ifndef BRANCHLESS_CABAC_DECODER
+ if(c->low < (c->range<<(CABAC_BITS+1))){
bit= s&1;
- *state= c->mps_state[s];
+ *state= ff_h264_mps_state[s];
renorm_cabac_decoder_once(c);
}else{
- bit= ff_h264_norm_shift[RangeLPS>>19];
- c->low -= c->range;
- *state= c->lps_state[s];
+ 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 & 0xFFFF)){
+ if(!(c->low & CABAC_MASK)){
refill2(c);
}
}
-#else
- lps_mask= (c->range - c->low)>>31;
+#else /* BRANCHLESS_CABAC_DECODER */
+ lps_mask= ((c->range<<(CABAC_BITS+1)) - c->low)>>31;
- c->low -= c->range & lps_mask;
+ c->low -= (c->range<<(CABAC_BITS+1)) & lps_mask;
c->range += (RangeLPS - c->range) & lps_mask;
s^=lps_mask;
- *state= c->mps_state[s];
+ *state= (ff_h264_mlps_state+128)[s];
bit= s&1;
- lps_mask= ff_h264_norm_shift[c->range>>(CABAC_BITS+3)];
+ lps_mask= ff_h264_norm_shift[c->range];
c->range<<= lps_mask;
c->low <<= lps_mask;
if(!(c->low & CABAC_MASK))
refill2(c);
-#endif
-#endif
+#endif /* BRANCHLESS_CABAC_DECODER */
+#endif /* ARCH_X86 && HAVE_7REGS && HAVE_EBX_AVAILABLE && !defined(BROKEN_RELOCATIONS) */
return bit;
}
-static int get_cabac_bypass(CABACContext *c){
+static int av_noinline av_unused get_cabac_noinline(CABACContext *c, uint8_t * const state){
+ return get_cabac_inline(c,state);
+}
+
+static int av_unused get_cabac(CABACContext *c, uint8_t * const state){
+ return get_cabac_inline(c,state);
+}
+
+static int av_unused 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"
+ "cltd \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);
- if(c->low < c->range){
+ range= c->range<<(CABAC_BITS+1);
+ if(c->low < range){
return 0;
}else{
- c->low -= c->range;
+ c->low -= range;
return 1;
}
+#endif
+}
+
+
+static av_always_inline int get_cabac_bypass_sign(CABACContext *c, int val){
+#if ARCH_X86 && HAVE_EBX_AVAILABLE
+ __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"
+ "cltd \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
}
/**
*
* @return the number of bytes read or 0 if no end
*/
-static int get_cabac_terminate(CABACContext *c){
- c->range -= 4<<CABAC_BITS;
- if(c->low < c->range){
+static int av_unused get_cabac_terminate(CABACContext *c){
+ c->range -= 2;
+ if(c->low < c->range<<(CABAC_BITS+1)){
renorm_cabac_decoder_once(c);
return 0;
}else{
}
}
+#if 0
/**
- * get (truncated) unnary binarization.
+ * Get (truncated) unary binarization.
*/
static int get_cabac_u(CABACContext *c, uint8_t * state, int max, int max_index, int truncated){
int i;
}else
return i;
}
+#endif /* 0 */
+
+#endif /* AVCODEC_CABAC_H */