Re:New inline assembly syntax available in Rust nightly
by jlebar on Tuesday June 09, 2020 @05:33PM
(#23471148)
> 1. It’s the syntax in the manual. The last thing I want to do when reading or writing asm is to mentally translate from the manual to AT&T syntax.
Right! I worked on C++ compilers for years and I don't even know where is the canonical book of AT&T mnemonics. At the rate that Intel is adding new instructions, using anything other than their official docs (and thus their official names) seems nuts.
Re:New inline assembly syntax available in Rust nightly
by amluto on Tuesday June 09, 2020 @08:02PM
(#23472407)
I'm quite confident that the canonical book of AT&T x86 assembler does not exist. There is the canonical book of Intel asm (the SDM), the canonical book of AMD asm (the APM), and the almsot canonical book of upcoming Intel asm (the ISE). Sadly, these documents are not generally entirely consistent with each other, but they all agree that the Intel syntax is the syntax.
1. It’s the syntax in the manual. The last thing I want to do when reading or writing asm is to mentally translate from the manual to AT&T syntax.
2. Addressing like (%rax) is tolerably. But the AT&T scale * index + offset syntax is inexcusable. Give me the verbose Intel addressing syntax any day, please.
(As a kernel programmer, I’m more familiar with AT&T. I still hate it. I’m morbidly curious how Intel syntax ought to handle things like SGDT. Maybe SGDT SIXBYTE PTR [address]? The fact that four bytes is called a DWORD isn’t great.)