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#include "entcode.h"
void ec_byte_reset(ec_byte_buffer *_b){
_b->ptr=_b->buf;
}
long ec_byte_bytes(ec_byte_buffer *_b){
return _b->ptr-_b->buf;
}
unsigned char *ec_byte_get_buffer(ec_byte_buffer *_b){
return _b->buf;
}
int ec_ilog(ec_uint32 _v){
#if defined(EC_CLZ)
return EC_CLZ0-EC_CLZ(_v);
#else
/*On a Pentium M, this branchless version tested as the fastest on
1,000,000,000 random 32-bit integers, edging out a similar version with
branches, and a 256-entry LUT version.*/
int ret;
int m;
ret=!!_v;
m=!!(_v&0xFFFF0000)<<4;
_v>>=m;
ret|=m;
m=!!(_v&0xFF00)<<3;
_v>>=m;
ret|=m;
m=!!(_v&0xF0)<<2;
_v>>=m;
ret|=m;
m=!!(_v&0xC)<<1;
_v>>=m;
ret|=m;
ret+=!!(_v&0x2);
return ret;
#endif
}
int ec_ilog64(ec_uint64 _v){
#if defined(EC_CLZ64)
return EC_CLZ64_0-EC_CLZ64(_v);
#else
ec_uint32 v;
int ret;
int m;
ret=!!_v;
m=!!(_v&0xFFFFFFFF00000000)<<5;
v=(ec_uint32)(_v>>m);
ret|=m;
m=!!(v&0xFFFF0000)<<4;
v>>=m;
ret|=m;
m=!!(v&0xFF00)<<3;
v>>=m;
ret|=m;
m=!!(v&0xF0)<<2;
v>>=m;
ret|=m;
m=!!(v&0xC)<<1;
v>>=m;
ret|=m;
ret+=!!(v&0x2);
return ret;
#endif
}
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