Register Allocators Documentation

Project Infrastructure LLVM Dev List Archives
1

Hi all,

I am interested in the spill code which is produced by the register allocators.

Therefore I wanted to ask if there is some Documentation in which these allocators are described, or that explains how the register spilling works in detail.

Regards

Jannis

2

AFAIK, you can refer previous LLVMDevs' slides to get a general idea
on spilling,

  - http://llvm.org/devmtg/2008-08/Cheng_RegisterAllocation.pdf
  - http://llvm.org/devmtg/2009-10/RegisterAllocationFutureWorks.pdf
  - http://llvm.org/devmtg/2011-11/Olesen_RegisterAllocation.pdf

But I don't know if there is article describing spilling in detail around.

HTH,
chenwj

3

There is also a good blog post about the greedy allocator (default when optimizing):
http://blog.llvm.org/2011/09/greedy-register-allocation-in-llvm-30.html

but to really learn the details you have to read the sourcecode.

  • Matthias
4

Thank you for your replies, i will look into it.

Regards

Jannis