already intrigued. The whole "threaded inlining" thing is something I've never thought about or done before but is really an elegant way to hijack
the compiler to do your work for you.
Basically the compiler writes your machine code for you anyhow. I'm quite curious about the claims that it achieves 70% of native performance (which
is really quite good) in microbenchmarks. It also seems to me like this threaded inlining might be a way in which you could swap in your own native code if
you wanted to do optimization. I had been thinking in assembler when thinking about how this could be done and for some reason it didn't occur to me to do
some of those tricks with C and let it worry about the rest.
I'm not sure what this inlining and the such means for garbage collection, error reporting and stack allocation but it is really nifty. I had been thinking for some
time that interpreted code was kind of dumb. That maybe just ditching the entire concept of non-JITing was the best thing. Sure you pay a penalty for startup time.
however, the more I think about it, since JITing is tied to classes and classes are tied to classloaders then any kind of serialization, scoping/etc would be a problem. One could walk around this by not obeying CL x FQN semantics for JIT purposes, but then you have to do some kind of binary analysis which could frankly be worse,
especially with the possibility of custom classloaders (don't you hate those ha ha ha -- those who will know -- know).
So I think there will be intepreted code and some kind of "patch in" for hot methods similar to hotspot. I have to say though that I rather like the idea of eager JIT-compiling all
base libraries at startup (toggleable of course). One of the things I like about this inlining is that it practically means that Harmony could achieve a near-decent degree of performance on nearly every platform that GCC supports. That seems like a rather cool thing.
I'm still wrapping my mind around the issue with GETSTATIC and function calls. I see what they mean about the performance issue of checking to see if the class is loaded and having to make a function call, but isn't that still a problem with native code too? How is this specific to the method of inlining?
-Andy
Davanum Srinivas wrote:
Andy,
check the wiki. there are some papers of interest.
-- dims
On 5/13/05, [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote:
It has been a considerable time since I did programming at that level but can someone tell me how:
If you are running code, generate some binary code, how do you schedule it to run on the processor (and preferably in an unbounded way). I believe IIRC you can copy it into the code segment. Can someone point me to a good reference or better yet some reasonably well written source which does this?
Thank you very much.
-andy -- Andrew C. Oliver SuperLink Software, Inc.
Java to Excel using POI http://www.superlinksoftware.com/services/poi Commercial support including features added/implemented, bugs fixed.
-- Andrew C. Oliver SuperLink Software, Inc.
Java to Excel using POI http://www.superlinksoftware.com/services/poi Commercial support including features added/implemented, bugs fixed.
