I thought I'd begin a discussion as to how to improve performance of the
rustc compiler.
First off, I do not see any way we can improve *general* compiler
performance by an order of magnitude. The language is simply designed to
favor safety and expressivity over compile-time performance.
I realized I forgot some things.
# Garbage collection
* Not generating reference count manipulations (which would be possible
if we switched to tracing GC) improves code generation speed. I created
a test that resulted in a 22.5% improvement in LLVM pass speed. Not an
order of magnitude
