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20:16:11
jakewalsh
drmeister: how should I get started looking into the various llvm pass optimizations?
20:21:15
Bike
if you run `opt -O3 -print-after-all -o=thing-after-O3.ll thing.ll` it'll show you the effect of every single pass. might want to `2>wherever` to put it in a file. you can get an ll from lisp by compile-file-ing anything and running llvm-dis on the resulting bc file.
20:21:32
Bike
https://llvm.org/docs/Passes.html the list of passes is here, but obviously there's not a lot of description
20:21:48
Bike
i don't know if you're familiar with lisp at all, but i can show you that sort of stuff if you need it
20:23:46
jakewalsh
Bike: thanks! I've started reading/working through Practical Common Lisp but I'm definitely still a novice in the language
20:24:53
Bike
you have some experience programming, right? i don't suppose you've ever looked into the murky abyss of compiler internals before?
20:27:42
jakewalsh
yeah, I have some experience in python and C - I've taken a standard undergrad computer systems (the standard one everyone rips from CMU - caches, shells, malloc, x86 assembly, etc) but that's the extent of my lower-level knowledge
20:28:43
pfdietz
"Obscure, profound it was, and nebulous, So that by fixing on its depths my sight -- Nothing whatever I discerned therein." -- Dante on compiler internals
20:30:03
Bike
for now i guess you should learn lisp and llvm-ir. for the latter, what i'd say you should do is write some basic (like very small) C programs, and look at the llvm-ir for them, then crossref with https://llvm.org/docs/LangRef.html until it makes sense
20:31:16
Bike
if you have clang installed you can get llvm-ir by doing `clang file.c -S -emit-llvm -o wherever.ll`
4:24:29
Kevslinger
beach: I'm in Seattle for the summer. I'll be headed back to Philly for my last year of undergrad in a couple weeks
4:27:25
Kevslinger
Long story short is I love working with drmeister and I love Lisp, but I need to start transitioning towards areas of focus for grad school
4:30:00
Kevslinger
I'll make it out to an ELS at some point in the near future. I loved it, seems like such a good community to be a part of.