ctSwapBit

void ctSwapBit(T)(uint  doSwap,  ref  T a,  ref  T b) if (is(T ==  ubyte)  ||  is(T ==  ushort)  ||  is(T ==  uint)
             ||  is(T ==  ulong))

pure nothrow @nogc @safe

Conditionally swaps two integers using an already normalized bit.

Unlike ctSwap, this primitive deliberately accepts only zero or one, allowing the mask conversion to use unsigned subtraction without a comparison that an optimizer may lower to control flow.

Parameters

`doSwap`	Zero or one.
`a`	First value.
`b`	Second value.