[Vm-dev] [64 bits] Object pointers in jitted code

Javier Pimás elpochodelagente at gmail.com
Wed Feb 28 13:16:33 UTC 2018


Hi! This time I'm investigating how cog jit handles pointers to objects in
native code. In x86-32 its easier because you have immediates of the size
of a pointer, but in x64 the immediates are restricted to 32bits (and I
think less in arm). So I wonder how people works around that, if using a
movabs instruction every time you need a pointer or if doing something
else. I found a mail in the list dated from 2011 (titled "questions about
cog internals") where you (Eliot) said that pointers were inlined in jit
code, but I don't know if that's still the case. Looking at the slang code
I found CogOutOfLineLiteralsX64Compiler, but it seems it is not used (yet?).

Cheers!
Pocho

-- 
Javier Pimás
Ciudad de Buenos Aires
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.squeakfoundation.org/pipermail/vm-dev/attachments/20180228/159af5de/attachment.html>


More information about the Vm-dev mailing list