Set Bits Optimization | Dataford Interview Questions

Intel Atom® x6000E firmware frequently inspects fixed-width control and status registers. Implement an optimized function that returns the number of set bits in a nonnegative integer represented with a specified number of bits.

The implementation should use parallel bit-counting operations rather than examining each bit individually. Treat value as an unsigned width-bit register value.

Formal Specification

Implement count_set_bits(value, width).

Input: value, a nonnegative integer, and width, an integer from 1 through 64.
Output: An integer equal to the number of 1 bits in the low width bits of value.
Inputs satisfy 0 <= value < 2 ** width.

Constraints

1 <= width <= 64
0 <= value < 2 ** width
The value represents an unsigned fixed-width register
Do not use string conversion or a built-in population-count method

Function Signature

def count_set_bits(value, width):

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