Function ceilPowerOfTwoPromote [src]

Returns the next power of two (if the value is not already a power of two). Only unsigned integers can be used. Zero is not an allowed input. Result is a type with 1 more bit than the input type.

Prototype

 pub fn ceilPowerOfTwoPromote(comptime T: type, value: T) std.meta.Int(@typeInfo(T).int.signedness, @typeInfo(T).int.bits + 1)

Parameters

T: typevalue: T

Example

 test ceilPowerOfTwoPromote {
    try testCeilPowerOfTwoPromote();
    try comptime testCeilPowerOfTwoPromote();
}

Source

  pub fn ceilPowerOfTwoPromote(comptime T: type, value: T) std.meta.Int(@typeInfo(T).int.signedness, @typeInfo(T).int.bits + 1) {
    comptime assert(@typeInfo(T) == .int);
    comptime assert(@typeInfo(T).int.signedness == .unsigned);
    assert(value != 0);
    const PromotedType = std.meta.Int(@typeInfo(T).int.signedness, @typeInfo(T).int.bits + 1);
    const ShiftType = std.math.Log2Int(PromotedType);
    return @as(PromotedType, 1) << @as(ShiftType, @intCast(@typeInfo(T).int.bits - @clz(value - 1)));
}  