CS:APP example uses idivq with two operands?

Question

I am reading about x86-64 (and assembly in general) through the book \"computer systems a programmer\'s perspective\"(3rd edition). The author, in compliance with other sour

Answer 1

I think your book has made a mistake.

idivq only has one operand. If I try to assemble this snippet:

idivq $9, %rcx

I get this error:

test.s: Assembler messages:
test.s:1: Error: operand type mismatch for `idiv'

This works:

idivq %rcx

but you probably already know that.

It may also be a macro (unlikely, but possible. credit to @HansPassant for this).

Perhaps you should contact the book's author so that they can add an entry to the errata.