INNER CODE UNIT · TypeScript
sigma16_32
paulmillr/noble-ciphers · src/_arx.ts:68
const sigma16_32 = /* @__PURE__ */ (() => swap32IfBE(u32(encodeStr('expand 16-byte k'))))();
// RFC 8439 §2.3 / RFC 7539 §2.3 define words 0-3 as
// `0x61707865 0x3320646e 0x79622d32 0x6b206574`, i.e. `expand 32-byte k`.
const sigma32_32 = /* @__PURE__ */ (() => swap32IfBE(u32(encodeStr('expand 32-byte k'))))();
/**
* Rotates a 32-bit word left.
* @param a - Input word.
* @param b - Rotation count in bits.
* @returns Rotated 32-bit word.
* @example
* Moves the top byte of `0x12345678` into the low byte position.
* ```ts
* rotl(0x12345678, 8);
* ```
*/
export function rotl(a: number, b: number): number {
return (a << b) | (a >>> (32 - b));