Difference between mov $0x8,%edx and mov 0x8,%edx

[suryasantu]

Hi All,
I saw the following two instructions in the objdump of a C Program.

mov $0x8,%edx

mov 0x8,%edx

What is the difference between the two instructions.
Does $ have any significance?

My understanding for mov 0x8,%edx is moving the value 8 into edx register.

Thanks in Advance

Regards
Surya Santosh

[Hobson]

I am not very familiar with AT&T syntax, so I hope that following info is correct:

mov $0x8,%edx - here $ means that following value is a numeral. Tis instruction moves value of 8 into edx register

mov 0x8,%edx - here 0x8 is not a literal, its an address. This instruction moves value stored at memory location 0x8 (of default data segment) into register edx.

Hope this helps
Hob

[philkr]

My understanding for mov 0x8,%edx is moving the value 8 into edx register.

Isn't this supposed to be "mov edx, 8h". And I think addressed are placed into square brackets like this [8h]. But it's only a guess.

[Hobson]

Isn't this supposed to be "mov edx, 8h". And I think addressed are placed into square brackets like this [8h]. But it's only a guess.

It is, but when using Intel assembly syntax. AT&T syntax (A.K.A. GAS assembly syntax) is quite different

Regards,
Hob