flat assembler
Message board for the users of flat assembler.
![]() |
Author |
|
Teehee
[see image]
When/why compiler will choose FF/0 instead 40+rd if using a register?
_________________ Sorry if bad english. |
||||||||||
![]() |
|
b1528932
in long mode 40+ is REX prefix, only way to encode inc/dec is by modrm opcode.
|
|||
![]() |
|
revolution
Teehee wrote: [see image] In 64-bit code fasm has no choice and "chooses" the two-byte variant. |
|||
![]() |
|
Teehee
hmm.. so is there many ways to do the same?
Manual says FE /0 is to r/m8, but when i look to inc al it shows me: Code: FEC0 inc al what that C mean? from where it comes? Last edited by Teehee on 10 Jul 2010, 00:11; edited 1 time in total |
|||
![]() |
|
revolution
Teehee wrote: what that C mean? from where it comes? |
|||
![]() |
|
Teehee
oh.. i didn't see yet.. that must happen when you don't use linear reading
![]() sorry to annoy you, uncle revolution. ![]() _________________ Sorry if bad english. |
|||
![]() |
|
< Last Thread | Next Thread > |
Forum Rules:
|
Copyright © 1999-2020, Tomasz Grysztar. Also on GitHub, YouTube, Twitter.
Website powered by rwasa.