The advantage of the bit arithmetic in C language

Bit arithmetic acceleration technique
1. If you multiply the value of the previous 2, you can use the left shift operation to accelerate the 300%

x = x * 2;
x = x * 64;
Switch
x = x << 1; 2 = 21
x = x << 6; 64 = 26

2. If the number of multiples in addition to the previous 2, you can use the right-shift operation to accelerate 350%

x = X/2;
x = X/64;
Switch

x = x >> 1;//2 = 21
x = x >> 6;//64 = 26

3. numeric to integer acceleration 10%

x = Int (1.232)
Switch

x = 1.232 >> 0;

4. swap two values (swap) and use XOR to accelerate 20%

var t:int = A;
A = b;
b = t;
equals
A = A^b;
b = a^b;
A = A^b;

5. sign conversion, can join 300%

i =-I.;
Switch
i = ~i + 1; Not notation
Or
i = (i ^-1) + 1; XOR notation

6. Take the remainder, if the divisor is a multiple of 2, can use the and operation to accelerate the 600%

x = 131% 4;
equals
x = 131 & (4-1);

7. Use the and operation to check if the integer is a multiple of 2 to accelerate the 600%

IsEven = (i% 2) = = 0;
equals
IsEven = (I & 1) = = 0;

8. Accelerate the writing of Math.Abs 600% 1, 2 is faster than the wording of 1 20%

Notation 1
i = x < 0? -x:x;

Notation 2

i = (x ^ (x >>))-(x >> 31);

Notation 3

i=x^ (~ (x>>31) +1) + (x>>31);

9. Compare if you have the same symbol after multiplying the two values, accelerating 35%

Eqsign = A * b > 0;
equals
Eqsign = a ^ b > 0;

Other bit arithmetic techniques
1. RGB Color Separation

var 24bitcolor:uint = 0xff00cc;
var r:uint = 24bitColor >> 16;
var g:uint = 24bitColor >> 8 & 0xFF;
var b:uint = 24bitColor & 0xFF;

2. RGB Color Merge

var r:uint = 0xFF;
var g:uint = 0x00;
var b:uint = 0xcc;
var 24bitcolor:uint = r << 16 | G << 8 | b

ps--especially in embedded, bit operations are particularly important!

The advantage of the bit arithmetic in C language