Difference between adding 0 and moving a register in MIPS

Question

What\'s the difference between:

add     rd, rs, zero

and

move    rd, rs

They both look like they should do th

Answer 1

The move is a pseudoinstruction, they do the same job. MIPS is a reduced instruction set computer (RISC), so the instruction size and hardware complexity are minimized by keeping the number of instructions small. However, MIPS defines pseudoinstructions that are not actually part of the instruction set but are commonly used by programmers and compilers.