NASM - The Netwide Assembler

NASM Forum => Programming with NASM => Topic started by: Borneq on August 12, 2010, 04:46:21 AM

Title: Format insns.dat
Post by: Borneq on August 12, 2010, 04:46:21 AM

Hi
What is format insns.dat?
 AAA is opcode 37, in insns.dat is AAA void \1\x37 086,NOLONG
\1 means one byte?
 AAD imm D5 ib   is AAD imm   \1\xD5\24   8086,SB,NOLONG
what means \1 at start, SB and NOLONG?

regards

Title: Re: Format insns.dat
Post by: Keith Kanios on August 12, 2010, 06:32:54 AM

IIRC, the top of assemble.c has the relevant information regarding the internal instruction format.

Title: Re: Format insns.dat
Post by: Cyrill Gorcunov on August 12, 2010, 06:52:00 PM

As Keith already pointed out -- see the head of assembly.c file it contains byte codes meanings.

About SB,NOLONG -- they are "Instruction template flags", perl script adds IF_ prefix to them
so you could find their meaning in insns.h file.

Hope this help.

Title: Re: Format insns.dat
Post by: Frank Kotler on August 13, 2010, 05:27:48 PM

If you're trying to figure out how Nasm works, Borneq, the format of insns.dat may help you. If what you're really looking for is an instruction set reference, try this one:

http://home.myfairpoint.net/fbkotler/nasmdocr.html

Best,
Frank