I am working on writing an assembly program and I would like to acquire some knowledge before I start on the looks of AT&T and Intel syntax when addressing xmm and fp. I know that in regular instructions a push when function on a byte is "pushb" in AT&T while "push byte" in Intel. Can anyone provide a similar comparison to when using xmm or fp? In sum I want to know how xmm operands are addressed
I'm not an AT&T fan/user, but the first place to start for intel would be the intel developer manuals(volumes 2a and 2b contain the instruction references), these list the sizes they operate on, which almost all intel syntax assemblers will try deduce (push will try narrow the variable or align it, depending on settings) if not specified, else you'll generally be using qword/dword for fp (for the likes of fld) and dword/qword/dqword for mmx/sse ops.