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/**
* ilog - Integer logarithm.
*
* ilog_32() and ilog_64() compute the minimum number of bits required to store
* an unsigned 32-bit or 64-bit value without any leading zero bits.
* This can also be thought of as the location of the highest set bit, with
* counting starting from one (so that 0 returns 0, 1 returns 1, and 2**31
* returns 32).
* When the value is known to be non-zero ilog32_nz() and ilog64_nz() can
* compile into as few as two instructions, one of which may get optimized out
* later.
* STATIC_ILOG_32 and STATIC_ILOG_64 allow computation on compile-time
* constants, so other compile-time constants can be derived from them.
*
* Example:
* #include <stdio.h>
* #include <limits.h>
* #include <ccan/ilog/ilog.h>
*
* int main(void){
* int i;
* printf("ilog32(0x%08X)=%i\n",0,ilog32(0));
* for(i=1;i<=STATIC_ILOG_32(USHRT_MAX);i++){
* uint32_t v;
* v=(uint32_t)1U<<(i-1);
* //Here we know v is non-zero, so we can use ilog32_nz().
* printf("ilog32(0x%08X)=%i\n",v,ilog32_nz(v));
* }
* return 0;
* }
*
* License: LGPL (v2 or later)
* Author: Timothy B. Terriberry <tterribe@xiph.org>
*/
#include <string.h>
#include <stdio.h>
#include "config.h"
int main(int _argc,const char *_argv[]){
/*Expect exactly one argument.*/
if(_argc!=2)return 1;
if(strcmp(_argv[1],"depends")==0){
printf("ccan/compiler\n");
return 0;
}
return 1;
}
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