What does an asterisk * before an address mean in x86-64 AT&T assembly?

Question

What does the following line mean:

...
401147: ff 24 c5 80 26 40 00    jmpq   *0x402680(,%rax,8)
...

What does the asterisk in front of the

Answer 1

As Necrolis wrote, Intel syntax makes it a bit more obvious, but RTN is really clearer. The line

jmpq   *0x402680(,%rax,8)

would be described in RTN by:

RIP <- M[0x402680 + (8 * RAX)]

where M is the system memory.

As such, we can write the general form jmpq *c(r1, r2, k), where c is an immediate constant, r1 and r2 are general purpose registers and k is either 1 (default), 2, 4 or 8:

RIP <- M[c + r1 + (k * r2)]