|
|
|
@ -335,7 +335,18 @@ int howManyBits(int x) { |
|
|
|
* Rating: 4 |
|
|
|
*/ |
|
|
|
unsigned floatScale2(unsigned uf) { |
|
|
|
return 2; |
|
|
|
unsigned sign = (0x80000000)&uf; |
|
|
|
unsigned exp = (0x7f800000)&uf; |
|
|
|
unsigned frac = (0x007fffff)&uf; |
|
|
|
if(exp == 0x7f800000) |
|
|
|
return uf; //如果是exp全为255,frac全是0就是无穷，不是就是NaN，都直接return |
|
|
|
if(exp == 0x00000000){ |
|
|
|
if(frac == 0x00000000) |
|
|
|
return uf; //exp全为0,frac全为0，则为0，0*2=0，原样不动 |
|
|
|
return (frac<<1)|sign|exp;//exp全为0,frac不全为0，注意到非规格化极小和规格化之间是连续的，即frac第一位为1时，左移会把exp变为非全0，回到规格化 |
|
|
|
} |
|
|
|
return (exp+0x00800000)|sign|frac; |
|
|
|
|
|
|
|
} |
|
|
|
/* |
|
|
|
* floatFloat2Int - Return bit-level equivalent of expression (int) f |
|
|
|
|
