Embodiments of methods and computer program products disclosed herein relate to processor architecture. One such method includes the processor obtaining an instruction. The instruction specifies an operation, and also specifies one of the registers as a source register and one of the registers as a destination register. The method also includes the processor obtaining an endian mode and determining that the instruction is an element-ordering-sensitive instruction. Based on the determination that the instruction is an element-ordering-sensitive instruction, the processor executes the instruction by performing the operation on the elements of the source register in accordance with the endian mode and writing a result of the operation to the destination register.