NASM - The Netwide Assembler

NASM Forum => Using NASM => Topic started by: Flo on June 17, 2017, 01:20:04 PM

Title: error: mismatch in operand sizes - why is that happening?
Post by: Flo on June 17, 2017, 01:20:04 PM

Hello there,
I have an instruction:

Code: [Select]

divsd xmm0, qword [ebp-0x18]
I get this error on the line where this instruction is located: "error: mismatch in operand sizes"

However

Code: [Select]

movsd xmm2, qword [ebp-0x18]seems to compile without an error.

Code is generated with "libudis86"

Why this is code wrong?

Edit:
However

Code: [Select]

divsd xmm0, [ebp-0x18]
Seems to result in the expected code

Title: Re: error: mismatch in operand sizes - why is that happening?
Post by: Frank Kotler on June 18, 2017, 02:22:52 AM

Hi Flo,

Dunno. Nasm only seems happy with no size specifier at all. Seems to me that it might be a bug(?).

(Thanks for your answers to other questions here!)

Best,
Frank