Comment by moonchild

3 years ago

By 'those optimisations' I assume you mean the specific rewrites, not superoptimisation? There has been some interesting recent work in rewrite inference, e.g. ruler. (I recall one such project did a survey and found that many—possibly a majority—of the rewrites it had generated automatically were not present in the hand-written corpuses of gcc and clang. I'm not sure if there was subsequent work to supplement gcc and clang; this was a few years ago now; I think they were looking at gcc 7.)

3 comments

moonchild

WalterBright 3 years ago

> I assume you mean the specific rewrites

Of course. The superoptimizer is too slow to use in the compiler itself.

petercooper 3 years ago

Maybe one day computers will be fast enough for a `gcc -O4`

    -O4
        Extreme optimization. GCC uses AI and quantum
        computation to warp space-time and invent 
        entirely new paradigms to make your programs 2% faster.
        Warning: May destroy your current universe.

colinb 3 years ago

https://news.ycombinator.com/item?id=10463312 talks about some in real time uses