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guenthert
"Not only is this JIT-compiler just 8 lines of code, it is also 20 times faster than invoking GCC or Clang on a roughly equivalent piece of C code."

So about as fast as TinyCcompiler (tcc)? Which produces faster code (in the context of HPC, elegance and ease of development takes a backseat to sheer performance, methinks)?

medo-bear
Why would you use C, or even assembly, when machine code is faster
guenthert
iiuc, that JIT-compiler uses the CL-image's compile function. That won't do any good, if in a HPC environment the actual heavy lifting is to be done on equipment other than the main CPU, e.g. a GPGPU or (earlier) Xeon Phi.
medo-bear
In the paper the author talks about compiling to CUDA
guenthert
"We already have code generators for turning kernels into Com- mon Lisp code and for turning a subset of kernels into C++ or CUDA code. Right now, our strategy is to use C++ and GCC when possible, and Common Lisp code otherwise. In the future, we plan to make the C++ generator obsolete by using SIMD optimized Common Lisp instead. Doing so would build on our previous work on s b - s i m d that we presented at the 15th European Lisp Symposium in Porto"

My take from that is, that for CUDA external tools are used today. Still, interesting work.

medo-bear
What do you mean by external tools?
hr0m
Wait, I know the author and will share the link so he can join here.
heisig
Heh, thanks :)

Petalisp author here - this ELS paper is just a preview. I'm also preparing a 160 page document (for my PhD) that will explain everything in more detail. I'll post on HN when it is available.

There is also a recording of my ELS talk on Twitch: https://www.twitch.tv/videos/2138821711?t=00h40m35s

medo-bear
Great work. I've been following Petalisp for a couple of years now. It is one of my favourite CL projects
EdwardCoffin
I was a bit surprised to see no mention of StarLisp [1]. Is this just a fundamentally different approach? I can imagine that targeting modern machines rather than the Connection Machine would be very different, but I thought the notations used in StarLisp were nice and could be reused.

[1] https://en.wikipedia.org/wiki/*Lisp