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#include <math.h>
#include <stdio.h>
#include <stdlib.h>
// s(-1) n(14) off(+1) x = x - ( x >> 14 )
// s( 1) n(-4) off( 0) x = ( x << 4 )
// s( 1) n( 8) off(-1) x = - x + ( x << 8 )
int main() {
int n, m, nsign;
// loop over all constructs in the form +-1*x^+-2n, n=-31..+31
for (n=-31; n<= 31; ++n )
for ( nsign=-1; nsign<=1; nsign+=2 )
{
// The one term only case
double v = (double)nsign * pow( 2.f, (double)n );
if( v > 0.f )
printf( "%0+25.21lf %08X x = %s ( x %s %2d )%s\n", log(v), abs((int)(67108864.f*log(v))), nsign==-1?"-":" ", n>=0?"<<":">>", (int)abs(n), " !RECOMMENDED!" );
// Loop over second term
for (m=-31; m<=31; ++m )
{
double v = pow( 2.f, (double)m ) + (double)nsign * pow( 2.f, (double)n );
if( v > 0.f ) {
printf( "%0+25.21lf %08X x = ( x %s %2d ) %s ( x %s %2d )%s\n", log(v), abs((int)(67108864.f*log(v))), m>=0?"<<":">>", (int)abs(m), nsign==-1?"-":"+", n>=0?"<<":">>", (int)abs(n), n*m?"":" !RECOMMENDED!" );
if( v < 1.f )
printf( "%0+25.21lf %08X x-= ( x %s %2d ) %s ( x %s %2d )\n", log(1.0f - v), abs((int)(67108864.f*log(1.0f - v))), m>=0?"<<":">>", (int)abs(m), nsign==-1?"-":"+", n>=0?"<<":">>", (int)abs(n) );
}
}
}
return 0;
}
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