Sanitise get_bits macros, part 2

These whitespace changes improve the readability of the get_bits
macros.

Signed-off-by: Mans Rullgard <mans@mansr.com>
oldabi
Mans Rullgard 14 years ago
parent bf5f9b528b
commit fb5c841d5f
  1. 378
      libavcodec/get_bits.h

@ -125,56 +125,46 @@ for examples see get_bits, show_bits, skip_bits, get_vlc
#ifdef ALT_BITSTREAM_READER #ifdef ALT_BITSTREAM_READER
# define MIN_CACHE_BITS 25 # define MIN_CACHE_BITS 25
# define OPEN_READER(name, gb)\ # define OPEN_READER(name, gb) \
unsigned int name##_index= (gb)->index;\ unsigned int name##_index = (gb)->index; \
int name##_cache= 0 int name##_cache = 0
# define CLOSE_READER(name, gb)\ # define CLOSE_READER(name, gb) (gb)->index = name##_index
(gb)->index= name##_index
# ifdef ALT_BITSTREAM_READER_LE # ifdef ALT_BITSTREAM_READER_LE
# define UPDATE_CACHE(name, gb)\ # define UPDATE_CACHE(name, gb) \
name##_cache= AV_RL32( ((const uint8_t *)(gb)->buffer)+(name##_index>>3) ) >> (name##_index&0x07) name##_cache = AV_RL32(((const uint8_t *)(gb)->buffer)+(name##_index>>3)) >> (name##_index&0x07)
# define SKIP_CACHE(name, gb, num)\ # define SKIP_CACHE(name, gb, num) name##_cache >>= (num)
name##_cache >>= (num)
# else # else
# define UPDATE_CACHE(name, gb)\ # define UPDATE_CACHE(name, gb) \
name##_cache= AV_RB32( ((const uint8_t *)(gb)->buffer)+(name##_index>>3) ) << (name##_index&0x07) name##_cache = AV_RB32(((const uint8_t *)(gb)->buffer)+(name##_index>>3)) << (name##_index&0x07)
# define SKIP_CACHE(name, gb, num)\ # define SKIP_CACHE(name, gb, num) name##_cache <<= (num)
name##_cache <<= (num)
# endif # endif
// FIXME name? // FIXME name?
# define SKIP_COUNTER(name, gb, num)\ # define SKIP_COUNTER(name, gb, num) name##_index += (num)
name##_index += (num)
# define SKIP_BITS(name, gb, num)\ # define SKIP_BITS(name, gb, num) do { \
do {\ SKIP_CACHE(name, gb, num); \
SKIP_CACHE(name, gb, num);\ SKIP_COUNTER(name, gb, num); \
SKIP_COUNTER(name, gb, num);\ } while (0)
} while (0)
# define LAST_SKIP_BITS(name, gb, num) SKIP_COUNTER(name, gb, num) # define LAST_SKIP_BITS(name, gb, num) SKIP_COUNTER(name, gb, num)
# define LAST_SKIP_CACHE(name, gb, num) # define LAST_SKIP_CACHE(name, gb, num)
# ifdef ALT_BITSTREAM_READER_LE # ifdef ALT_BITSTREAM_READER_LE
# define SHOW_UBITS(name, gb, num)\ # define SHOW_UBITS(name, gb, num) zero_extend(name##_cache, num)
zero_extend(name##_cache, num)
# define SHOW_SBITS(name, gb, num)\ # define SHOW_SBITS(name, gb, num) sign_extend(name##_cache, num)
sign_extend(name##_cache, num)
# else # else
# define SHOW_UBITS(name, gb, num)\ # define SHOW_UBITS(name, gb, num) NEG_USR32(name##_cache, num)
NEG_USR32(name##_cache, num)
# define SHOW_SBITS(name, gb, num)\ # define SHOW_SBITS(name, gb, num) NEG_SSR32(name##_cache, num)
NEG_SSR32(name##_cache, num)
# endif # endif
# define GET_CACHE(name, gb)\ # define GET_CACHE(name, gb) ((uint32_t)name##_cache)
((uint32_t)name##_cache)
static inline int get_bits_count(const GetBitContext *s){ static inline int get_bits_count(const GetBitContext *s){
return s->index; return s->index;
@ -188,67 +178,60 @@ static inline void skip_bits_long(GetBitContext *s, int n){
# define MIN_CACHE_BITS 32 # define MIN_CACHE_BITS 32
# define OPEN_READER(name, gb)\ # define OPEN_READER(name, gb) \
int name##_bit_count=(gb)->bit_count;\ int name##_bit_count = (gb)->bit_count; \
uint32_t name##_cache0= (gb)->cache0;\ uint32_t name##_cache0 = (gb)->cache0; \
uint32_t name##_cache1= (gb)->cache1;\ uint32_t name##_cache1 = (gb)->cache1; \
uint32_t * name##_buffer_ptr=(gb)->buffer_ptr uint32_t *name##_buffer_ptr = (gb)->buffer_ptr
# define CLOSE_READER(name, gb) do {\ # define CLOSE_READER(name, gb) do { \
(gb)->bit_count= name##_bit_count;\ (gb)->bit_count = name##_bit_count; \
(gb)->cache0= name##_cache0;\ (gb)->cache0 = name##_cache0; \
(gb)->cache1= name##_cache1;\ (gb)->cache1 = name##_cache1; \
(gb)->buffer_ptr= name##_buffer_ptr;\ (gb)->buffer_ptr = name##_buffer_ptr; \
} while (0) } while (0)
# define UPDATE_CACHE(name, gb) do {\ # define UPDATE_CACHE(name, gb) do { \
if(name##_bit_count > 0){\ if(name##_bit_count > 0){ \
const uint32_t next= av_be2ne32( *name##_buffer_ptr );\ const uint32_t next = av_be2ne32(*name##_buffer_ptr); \
name##_cache0 |= NEG_USR32(next,name##_bit_count);\ name##_cache0 |= NEG_USR32(next, name##_bit_count); \
name##_cache1 |= next<<name##_bit_count;\ name##_cache1 |= next << name##_bit_count; \
name##_buffer_ptr++;\ name##_buffer_ptr++; \
name##_bit_count-= 32;\ name##_bit_count -= 32; \
}\ } \
} while (0) } while (0)
#if ARCH_X86 #if ARCH_X86
# define SKIP_CACHE(name, gb, num)\ # define SKIP_CACHE(name, gb, num) \
__asm__(\ __asm__("shldl %2, %1, %0 \n\t" \
"shldl %2, %1, %0 \n\t"\ "shll %2, %1 \n\t" \
"shll %2, %1 \n\t"\ : "+r" (name##_cache0), "+r" (name##_cache1) \
: "+r" (name##_cache0), "+r" (name##_cache1)\ : "Ic" ((uint8_t)(num)))
: "Ic" ((uint8_t)(num))\
)
#else #else
# define SKIP_CACHE(name, gb, num) do {\ # define SKIP_CACHE(name, gb, num) do { \
name##_cache0 <<= (num);\ name##_cache0 <<= (num); \
name##_cache0 |= NEG_USR32(name##_cache1,num);\ name##_cache0 |= NEG_USR32(name##_cache1,num); \
name##_cache1 <<= (num);\ name##_cache1 <<= (num); \
} while (0) } while (0)
#endif #endif
# define SKIP_COUNTER(name, gb, num)\ # define SKIP_COUNTER(name, gb, num) name##_bit_count += (num)
name##_bit_count += (num)
# define SKIP_BITS(name, gb, num)\ # define SKIP_BITS(name, gb, num) do { \
do {\ SKIP_CACHE(name, gb, num); \
SKIP_CACHE(name, gb, num);\ SKIP_COUNTER(name, gb, num); \
SKIP_COUNTER(name, gb, num);\ } while (0)
} while (0)
# define LAST_SKIP_BITS(name, gb, num) SKIP_BITS(name, gb, num) # define LAST_SKIP_BITS(name, gb, num) SKIP_BITS(name, gb, num)
# define LAST_SKIP_CACHE(name, gb, num) SKIP_CACHE(name, gb, num) # define LAST_SKIP_CACHE(name, gb, num) SKIP_CACHE(name, gb, num)
# define SHOW_UBITS(name, gb, num)\ # define SHOW_UBITS(name, gb, num) NEG_USR32(name##_cache0, num)
NEG_USR32(name##_cache0, num)
# define SHOW_SBITS(name, gb, num)\ # define SHOW_SBITS(name, gb, num) NEG_SSR32(name##_cache0, num)
NEG_SSR32(name##_cache0, num)
# define GET_CACHE(name, gb)\ # define GET_CACHE(name, gb) name##_cache0
(name##_cache0)
static inline int get_bits_count(const GetBitContext *s){ static inline int get_bits_count(const GetBitContext *s) {
return ((uint8_t*)s->buffer_ptr - s->buffer)*8 - 32 + s->bit_count; return ((uint8_t*)s->buffer_ptr - s->buffer)*8 - 32 + s->bit_count;
} }
@ -257,7 +240,7 @@ static inline void skip_bits_long(GetBitContext *s, int n){
re_bit_count += n; re_bit_count += n;
re_buffer_ptr += re_bit_count>>5; re_buffer_ptr += re_bit_count>>5;
re_bit_count &= 31; re_bit_count &= 31;
re_cache0 = av_be2ne32( re_buffer_ptr[-1] ) << re_bit_count; re_cache0 = av_be2ne32(re_buffer_ptr[-1]) << re_bit_count;
re_cache1 = 0; re_cache1 = 0;
UPDATE_CACHE(re, s); UPDATE_CACHE(re, s);
CLOSE_READER(re, s); CLOSE_READER(re, s);
@ -276,8 +259,8 @@ static inline int get_xbits(GetBitContext *s, int n){
register int32_t cache; register int32_t cache;
OPEN_READER(re, s); OPEN_READER(re, s);
UPDATE_CACHE(re, s); UPDATE_CACHE(re, s);
cache = GET_CACHE(re,s); cache = GET_CACHE(re, s);
sign=(~cache)>>31; sign = ~cache >> 31;
LAST_SKIP_BITS(re, s, n); LAST_SKIP_BITS(re, s, n);
CLOSE_READER(re, s); CLOSE_READER(re, s);
return (NEG_USR32(sign ^ cache, n) ^ sign) - sign; return (NEG_USR32(sign ^ cache, n) ^ sign) - sign;
@ -287,7 +270,7 @@ static inline int get_sbits(GetBitContext *s, int n){
register int tmp; register int tmp;
OPEN_READER(re, s); OPEN_READER(re, s);
UPDATE_CACHE(re, s); UPDATE_CACHE(re, s);
tmp= SHOW_SBITS(re, s, n); tmp = SHOW_SBITS(re, s, n);
LAST_SKIP_BITS(re, s, n); LAST_SKIP_BITS(re, s, n);
CLOSE_READER(re, s); CLOSE_READER(re, s);
return tmp; return tmp;
@ -300,7 +283,7 @@ static inline unsigned int get_bits(GetBitContext *s, int n){
register int tmp; register int tmp;
OPEN_READER(re, s); OPEN_READER(re, s);
UPDATE_CACHE(re, s); UPDATE_CACHE(re, s);
tmp= SHOW_UBITS(re, s, n); tmp = SHOW_UBITS(re, s, n);
LAST_SKIP_BITS(re, s, n); LAST_SKIP_BITS(re, s, n);
CLOSE_READER(re, s); CLOSE_READER(re, s);
return tmp; return tmp;
@ -313,8 +296,7 @@ static inline unsigned int show_bits(GetBitContext *s, int n){
register int tmp; register int tmp;
OPEN_READER(re, s); OPEN_READER(re, s);
UPDATE_CACHE(re, s); UPDATE_CACHE(re, s);
tmp= SHOW_UBITS(re, s, n); tmp = SHOW_UBITS(re, s, n);
// CLOSE_READER(re, s)
return tmp; return tmp;
} }
@ -328,17 +310,17 @@ static inline void skip_bits(GetBitContext *s, int n){
static inline unsigned int get_bits1(GetBitContext *s){ static inline unsigned int get_bits1(GetBitContext *s){
#ifdef ALT_BITSTREAM_READER #ifdef ALT_BITSTREAM_READER
unsigned int index= s->index; unsigned int index = s->index;
uint8_t result= s->buffer[ index>>3 ]; uint8_t result = s->buffer[index>>3];
#ifdef ALT_BITSTREAM_READER_LE #ifdef ALT_BITSTREAM_READER_LE
result>>= (index&0x07); result >>= index & 7;
result&= 1; result &= 1;
#else #else
result<<= (index&0x07); result <<= index & 7;
result>>= 8 - 1; result >>= 8 - 1;
#endif #endif
index++; index++;
s->index= index; s->index = index;
return result; return result;
#else #else
@ -358,13 +340,13 @@ static inline void skip_bits1(GetBitContext *s){
* reads 0-32 bits. * reads 0-32 bits.
*/ */
static inline unsigned int get_bits_long(GetBitContext *s, int n){ static inline unsigned int get_bits_long(GetBitContext *s, int n){
if(n<=MIN_CACHE_BITS) return get_bits(s, n); if (n <= MIN_CACHE_BITS) return get_bits(s, n);
else{ else {
#ifdef ALT_BITSTREAM_READER_LE #ifdef ALT_BITSTREAM_READER_LE
int ret= get_bits(s, 16); int ret = get_bits(s, 16);
return ret | (get_bits(s, n-16) << 16); return ret | (get_bits(s, n-16) << 16);
#else #else
int ret= get_bits(s, 16) << (n-16); int ret = get_bits(s, 16) << (n-16);
return ret | get_bits(s, n-16); return ret | get_bits(s, n-16);
#endif #endif
} }
@ -381,17 +363,17 @@ static inline int get_sbits_long(GetBitContext *s, int n) {
* shows 0-32 bits. * shows 0-32 bits.
*/ */
static inline unsigned int show_bits_long(GetBitContext *s, int n){ static inline unsigned int show_bits_long(GetBitContext *s, int n){
if(n<=MIN_CACHE_BITS) return show_bits(s, n); if (n <= MIN_CACHE_BITS) return show_bits(s, n);
else{ else {
GetBitContext gb= *s; GetBitContext gb = *s;
return get_bits_long(&gb, n); return get_bits_long(&gb, n);
} }
} }
static inline int check_marker(GetBitContext *s, const char *msg) static inline int check_marker(GetBitContext *s, const char *msg)
{ {
int bit= get_bits1(s); int bit = get_bits1(s);
if(!bit) if (!bit)
av_log(NULL, AV_LOG_INFO, "Marker bit missing %s\n", msg); av_log(NULL, AV_LOG_INFO, "Marker bit missing %s\n", msg);
return bit; return bit;
@ -409,38 +391,38 @@ static inline int check_marker(GetBitContext *s, const char *msg)
static inline void init_get_bits(GetBitContext *s, static inline void init_get_bits(GetBitContext *s,
const uint8_t *buffer, int bit_size) const uint8_t *buffer, int bit_size)
{ {
int buffer_size= (bit_size+7)>>3; int buffer_size = (bit_size+7)>>3;
if(buffer_size < 0 || bit_size < 0) { if (buffer_size < 0 || bit_size < 0) {
buffer_size = bit_size = 0; buffer_size = bit_size = 0;
buffer = NULL; buffer = NULL;
} }
s->buffer= buffer; s->buffer = buffer;
s->size_in_bits= bit_size; s->size_in_bits = bit_size;
s->buffer_end= buffer + buffer_size; s->buffer_end = buffer + buffer_size;
#ifdef ALT_BITSTREAM_READER #ifdef ALT_BITSTREAM_READER
s->index=0; s->index = 0;
#elif defined A32_BITSTREAM_READER #elif defined A32_BITSTREAM_READER
s->buffer_ptr = (uint32_t*)((intptr_t)buffer&(~3)); s->buffer_ptr = (uint32_t*)((intptr_t)buffer & ~3);
s->bit_count = 32 + 8*((intptr_t)buffer&3); s->bit_count = 32 + 8*((intptr_t)buffer & 3);
skip_bits_long(s, 0); skip_bits_long(s, 0);
#endif #endif
} }
static inline void align_get_bits(GetBitContext *s) static inline void align_get_bits(GetBitContext *s)
{ {
int n= (-get_bits_count(s)) & 7; int n = -get_bits_count(s) & 7;
if(n) skip_bits(s, n); if (n) skip_bits(s, n);
} }
#define init_vlc(vlc, nb_bits, nb_codes,\ #define init_vlc(vlc, nb_bits, nb_codes, \
bits, bits_wrap, bits_size,\ bits, bits_wrap, bits_size, \
codes, codes_wrap, codes_size,\ codes, codes_wrap, codes_size, \
flags)\ flags) \
init_vlc_sparse(vlc, nb_bits, nb_codes,\ init_vlc_sparse(vlc, nb_bits, nb_codes, \
bits, bits_wrap, bits_size,\ bits, bits_wrap, bits_size, \
codes, codes_wrap, codes_size,\ codes, codes_wrap, codes_size, \
NULL, 0, 0, flags) NULL, 0, 0, flags)
int init_vlc_sparse(VLC *vlc, int nb_bits, int nb_codes, int init_vlc_sparse(VLC *vlc, int nb_bits, int nb_codes,
const void *bits, int bits_wrap, int bits_size, const void *bits, int bits_wrap, int bits_size,
@ -451,13 +433,12 @@ int init_vlc_sparse(VLC *vlc, int nb_bits, int nb_codes,
#define INIT_VLC_USE_NEW_STATIC 4 #define INIT_VLC_USE_NEW_STATIC 4
void free_vlc(VLC *vlc); void free_vlc(VLC *vlc);
#define INIT_VLC_STATIC(vlc, bits, a,b,c,d,e,f,g, static_size)\ #define INIT_VLC_STATIC(vlc, bits, a,b,c,d,e,f,g, static_size) do { \
do {\ static VLC_TYPE table[static_size][2]; \
static VLC_TYPE table[static_size][2];\ (vlc)->table = table; \
(vlc)->table= table;\ (vlc)->table_allocated = static_size; \
(vlc)->table_allocated= static_size;\ init_vlc(vlc, bits, a,b,c,d,e,f,g, INIT_VLC_USE_NEW_STATIC); \
init_vlc(vlc, bits, a,b,c,d,e,f,g, INIT_VLC_USE_NEW_STATIC);\ } while (0)
} while (0)
/** /**
@ -466,62 +447,60 @@ do {\
* If the vlc code is invalid and max_depth>1, then the number of bits removed * If the vlc code is invalid and max_depth>1, then the number of bits removed
* is undefined. * is undefined.
*/ */
#define GET_VLC(code, name, gb, table, bits, max_depth)\ #define GET_VLC(code, name, gb, table, bits, max_depth) do { \
do {\ int n, nb_bits; \
int n, nb_bits;\ unsigned int index; \
unsigned int index;\ \
\ index = SHOW_UBITS(name, gb, bits); \
index= SHOW_UBITS(name, gb, bits);\ code = table[index][0]; \
code = table[index][0];\ n = table[index][1]; \
n = table[index][1];\ \
\ if (max_depth > 1 && n < 0) { \
if(max_depth > 1 && n < 0){\ LAST_SKIP_BITS(name, gb, bits); \
LAST_SKIP_BITS(name, gb, bits);\ UPDATE_CACHE(name, gb); \
UPDATE_CACHE(name, gb);\ \
\ nb_bits = -n; \
nb_bits = -n;\ \
\ index = SHOW_UBITS(name, gb, nb_bits) + code; \
index= SHOW_UBITS(name, gb, nb_bits) + code;\ code = table[index][0]; \
code = table[index][0];\ n = table[index][1]; \
n = table[index][1];\ if (max_depth > 2 && n < 0) { \
if(max_depth > 2 && n < 0){\ LAST_SKIP_BITS(name, gb, nb_bits); \
LAST_SKIP_BITS(name, gb, nb_bits);\ UPDATE_CACHE(name, gb); \
UPDATE_CACHE(name, gb);\ \
\ nb_bits = -n; \
nb_bits = -n;\ \
\ index = SHOW_UBITS(name, gb, nb_bits) + code; \
index= SHOW_UBITS(name, gb, nb_bits) + code;\ code = table[index][0]; \
code = table[index][0];\ n = table[index][1]; \
n = table[index][1];\ } \
}\ } \
}\ SKIP_BITS(name, gb, n); \
SKIP_BITS(name, gb, n);\ } while (0)
} while (0)
#define GET_RL_VLC(level, run, name, gb, table, bits, max_depth, need_update) do { \
#define GET_RL_VLC(level, run, name, gb, table, bits, max_depth, need_update)\ int n, nb_bits; \
do {\ unsigned int index; \
int n, nb_bits;\ \
unsigned int index;\ index = SHOW_UBITS(name, gb, bits); \
\ level = table[index].level; \
index= SHOW_UBITS(name, gb, bits);\ n = table[index].len; \
level = table[index].level;\ \
n = table[index].len;\ if (max_depth > 1 && n < 0) { \
\ SKIP_BITS(name, gb, bits); \
if(max_depth > 1 && n < 0){\ if (need_update) { \
SKIP_BITS(name, gb, bits);\ UPDATE_CACHE(name, gb); \
if(need_update){\ } \
UPDATE_CACHE(name, gb);\ \
}\ nb_bits = -n; \
\ \
nb_bits = -n;\ index = SHOW_UBITS(name, gb, nb_bits) + level; \
\ level = table[index].level; \
index= SHOW_UBITS(name, gb, nb_bits) + level;\ n = table[index].len; \
level = table[index].level;\ } \
n = table[index].len;\ run = table[index].run; \
}\ SKIP_BITS(name, gb, n); \
run= table[index].run;\ } while (0)
SKIP_BITS(name, gb, n);\
} while (0)
/** /**
@ -552,38 +531,45 @@ static av_always_inline int get_vlc2(GetBitContext *s, VLC_TYPE (*table)[2],
static inline void print_bin(int bits, int n){ static inline void print_bin(int bits, int n){
int i; int i;
for(i=n-1; i>=0; i--){ for (i = n-1; i >= 0; i--) {
av_log(NULL, AV_LOG_DEBUG, "%d", (bits>>i)&1); av_log(NULL, AV_LOG_DEBUG, "%d", (bits>>i)&1);
} }
for(i=n; i<24; i++) for (i = n; i < 24; i++)
av_log(NULL, AV_LOG_DEBUG, " "); av_log(NULL, AV_LOG_DEBUG, " ");
} }
static inline int get_bits_trace(GetBitContext *s, int n, char *file, const char *func, int line){ static inline int get_bits_trace(GetBitContext *s, int n, char *file,
int r= get_bits(s, n); const char *func, int line){
int r = get_bits(s, n);
print_bin(r, n); print_bin(r, n);
av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d bit @%5d in %s %s:%d\n", r, n, r, get_bits_count(s)-n, file, func, line); av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d bit @%5d in %s %s:%d\n",
r, n, r, get_bits_count(s)-n, file, func, line);
return r; return r;
} }
static inline int get_vlc_trace(GetBitContext *s, VLC_TYPE (*table)[2], int bits, int max_depth, char *file, const char *func, int line){ static inline int get_vlc_trace(GetBitContext *s, VLC_TYPE (*table)[2],
int show= show_bits(s, 24); int bits, int max_depth, char *file,
int pos= get_bits_count(s); const char *func, int line){
int r= get_vlc2(s, table, bits, max_depth); int show = show_bits(s, 24);
int len= get_bits_count(s) - pos; int pos = get_bits_count(s);
int bits2= show>>(24-len); int r = get_vlc2(s, table, bits, max_depth);
int len = get_bits_count(s) - pos;
int bits2 = show >> (24-len);
print_bin(bits2, len); print_bin(bits2, len);
av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d vlc @%5d in %s %s:%d\n", bits2, len, r, pos, file, func, line); av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d vlc @%5d in %s %s:%d\n",
bits2, len, r, pos, file, func, line);
return r; return r;
} }
static inline int get_xbits_trace(GetBitContext *s, int n, char *file, const char *func, int line){ static inline int get_xbits_trace(GetBitContext *s, int n, char *file,
int show= show_bits(s, n); const char *func, int line){
int r= get_xbits(s, n); int show = show_bits(s, n);
int r = get_xbits(s, n);
print_bin(show, n); print_bin(show, n);
av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d xbt @%5d in %s %s:%d\n", show, n, r, get_bits_count(s)-n, file, func, line); av_log(NULL, AV_LOG_DEBUG, "%5d %2d %3d xbt @%5d in %s %s:%d\n",
show, n, r, get_bits_count(s)-n, file, func, line);
return r; return r;
} }

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