Visual studio inline assembly direct jump

Question

I want to use inline assembly in visual studio to jump to a specific address. I tried this:

_asm {
    jmp 0x12345678
}

But the compiler says: "The opcode does not use operands of this type."

How can I do a direct jump?

Answer 1

As far as I understand it, MASM does not support this type of jump. You have a few options :

mov eax, 12345678h
jmp eax

or

push 12345678h 
ret

The first uses a register, the second incurs a performance hit because it rattles the CALL/RET pairing optimizations in the CPU. You could also use a typed constant or local variable, I think - this also consumes a few extra bytes. I don't think there's any other way, nor any direct, one-line means of performing a direct jump like this in MASM.

caveat : this assumes you are working in x86 code. Your OP suggests as much from the size of the jmp argument but if this is x64 then the answer will obviously be different.