std::math::bits

Status: experimental

Integer bit-manipulation operations (Go's math/bits shape).

API details and source

The implementation source contains the complete declarations and implementation notes. The table below lists canonical Gossamer call signatures; every item name links directly to its implementation file.

Item	Canonical signature or declaration	Description
add	fn add(x: u64, y: u64, carry: u64) -> (u64, u64)	x + y + carry; returns (sum, carry_out).
count_ones	fn count_ones(x: u64) -> i64	Number of set bits (popcount).
count_zeros	fn count_zeros(x: u64) -> i64	Number of clear bits.
div	fn div(hi: u64, lo: u64, y: u64) -> (u64, u64)	128-bit dividend / 64-bit divisor; returns (quotient, remainder).
leading_zeros	fn leading_zeros(x: u64) -> i64	Leading zero bit count.
len	fn len(x: u64) -> i64	Minimum bits required to represent x.
mul	fn mul(x: u64, y: u64) -> (u64, u64)	Full 128-bit product; returns (hi, lo).
reverse_bits	fn reverse_bits(x: u64) -> i64	Reverses bit order of x.
reverse_bytes	fn reverse_bytes(x: u64) -> i64	Reverses byte order of x.
rotate_left	fn rotate_left(x: u64, n: i64) -> u64	Rotates x left by n bits.
rotate_right	fn rotate_right(x: u64, n: i64) -> u64	Rotates x right by n bits.
sub	fn sub(x: u64, y: u64, borrow: u64) -> (u64, u64)	x - y - borrow; returns (diff, borrow_out).
trailing_zeros	fn trailing_zeros(x: u64) -> i64	Trailing zero bit count.