I agree that it does seem backwards initially to have OP DEST, SRC, but it does match the other ISAs that are still being used these days like ARM or PowerPC. I have found it really hard to go from working one day in PowerPC assembly to the next working in AT&T-format x86 because of the operand ordering. Plus all the other bits and pieces that make AT&T a pain, like the required sigils, LEA format, use of immediates with MOV, instruction size suffixes, etc.