#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "entcode.h"
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
}