Intel XED – x86 Encoder Decoder(intelxed.github.io)

114 pointsby peter_d_sherman7 anni fa9 comments

intelxed.github.io

https://intelxed.github.io/

5 comments

Intel is releasing the source of XED but canceling IACA which is built on top of XED. Color me confused. Still, this will be useful for a lot of projects to have this piece of infrastructure for such an important CISC ISA available under an Apache license. Boring as hell, but useful.

For example, ARM tests their ARM LLVM backend using a golden reference implementation. This is the MC Hammer test: encode/decode assemble/disassemble[1]. This can be the golden reference for the same with x86_64 and useful for GCC+LLVM.

[1] https://llvm.org/devmtg/2012-04-12/Slides/Richard_Barton.pdf

orodley7 anni fa

Intel released the source of XED a while ago, in December 2016. Not sure why it's popping up on HN now.

corysama7 anni fa

Probably inspired by it's use in https://news.ycombinator.com/item?id=19813993

dtornabene7 anni fa

There was a talk at Recon several years ago by Richard Johnson called "Go Speed Tracer" that goes into some of things built with a tool like this. Its a serious talk, dense with information, covers some guided fuzzing territory and alot about tracing engines (hence the name). He mentions xed by name in the talk and notes interestingly enough that despite Pin and xed being developed inhouse at intel there isn't a one-to-one parity between the silicon and the disassembler and subsequently Pin itself. Glad to be able to sift through the source now, thanks for posting this 'peter_d_sherman

Link for the talk https://www.youtube.com/watch?v=oWKDaD9wrWo

AdmVonSchneider7 anni fa

Anyone interested in accurate (and fast) instruction decoding for x86(-64) should also look into Zydis: https://github.com/zyantific/zydis

vardump7 anni fa

Anyone done any work to confirm how accurate XED is? Do all the decoded instruction lengths match with real hardware? Sure, it's from Intel, but I'd like to have something more. Other x86 decoders could have been better.

vectorEQ7 anni fa

XED is fairly accurate. prefer to use capstone, but i suppose it's what you're used to... i feel XED has more potential because it's from the vendor. at least for intel brand cpus.

sabas1237 anni fa

After tinkering for quite some time with multiple disassemblers I can confirm that XED is hands down the best in the market

gnufx7 anni fa

MAQAO (http://maqao.org/) might also be of interest.