[LLVMdev] Newbie question on front-end and code compaction

[Dale Johannesen]

On Sep 5, 2008, at 10:06 AMPDT, Mike Stump wrote:

> On Sep 4, 2008, at 8:03 PM, Bernardo Elayda wrote:
>> I'm also interested in helping out with compaction(making code with
>> a small footprint).
>
> People pointed out recently on the list that -Os doesn't work so
> well.  See the email from regehr at cs.utah.edu on Aug 20 on llvmdev.
> You should be able to work with him to get testcases, from there you
> just grind through them and find why they are bigger and reduce them.
> Failing that, just compile up any software and compare.  Should be
> lots of low hanging fruit.

Thread starts here:
http://lists.cs.uiuc.edu/pipermail/llvmdev/2008-August/016600.html
The last message points out inlining and unrolling heuristics as low- 
hanging fruit, and I agree.
But there is a lot more beyond that, particular instruction selection  
on x86.