Methods and apparatuses relating to high-performance authenticated encryption are described. A hardware accelerator may include a vector register to store an input vector of a round of an encryption operation; a circuit including a first data path including a first modular adder coupled to a first input from the vector register and a second input from the vector register, and a second modular adder coupled to the first modular adder and a second data path from the vector register, and the second data path including a first logical XOR circuit coupled to the second input and a third data path from the vector register, a first rotate circuit coupled to the first logical XOR circuit, a second logical XOR circuit coupled to the first rotate circuit and the third data path, and a second rotate circuit coupled to the second logical XOR circuit; and a control circuit to cause the first modular adder and the second modular adder of the first data path and the first logical XOR circuit, the second logical XOR circuit, the first rotate circuit, and the second rotate circuit of the second data path to perform a portion of the round according to one or more control values, and store a first result from the first data path for the portion and a second result from the second data path for the portion into the vector register.