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3:51:17
drmeister
If we change the cmp:%double% to :double-float then we could simplify the definition.
3:53:28
Bike
i can do a macro tomorrow. i was going to do one that includes the translate-primop body so everything's in one place
3:56:25
Bike
i don't think it makes sense to incorporate the intrinsic into the defprimop since some primops don't have corresponding intrinsics
4:00:17
drmeister
(disassemble '(lambda (x) (geom::ovector3-getx x)) :type :ir) says "Undefined function OVECTOR3-GETX"
4:03:27
Bike
https://github.com/clasp-developers/clasp/blob/main/src/lisp/kernel/cleavir/setup.lisp#L176-L192 add it in here, i think
4:03:43
Bike
yeah, this is all pretty unwieldly. i'll put together something more convenient tomorrow
4:15:42
Bike
i think the easiest solution would be if i define a cleavir-primop:primop special operator that takes the name as its first pseudo parameter
4:23:44
Bike
just to be clear, you probably don't want to use primops directly in the application code. you could do like (declaim (inline ovector3-getx)) (defun ovector3-getx (ovector3) (core:primop %ovector3-getx ovector3)) and then you have an actual function but the compiler can still work with obvious calls
4:25:50
Bike
and i might want to port the representation selection stuff from clasp to cleavir, it's pretty general
4:28:51
Bike
the short version is i got type inference going well enough that long stretches of floating point operations can be compiled without boxing and without making the compiler unusably slow
4:29:09
Bike
and it's generalizable to other type directed optimizations, though doing them while preserving safety is a little less obvious
11:51:14
drmeister
yitzi: For my bond through ring detection problem. The winding algorithm works on 2d planes. Molecular rings aren't flat. So I'm calculating a plane (centroid, normal) for each ring and projecting the ring into the plane and then calculating the intersection of each bond that cuts across the plane with the plane and then calculating the winding number.
11:54:04
yitzi
drmeister: Understand. I think there might be some other methods, but I haven't worked it out quite yet.
12:05:56
yitzi
drmeister: I think that there might be small errors possible if the bond is close to the edge of the ring due to projecting ring atoms onto plane that is not perpendicular to the bond in question.
12:08:10
yitzi
Basically. instead of find the ring plane, instead one would make a plane perpendicular to the bond by using a vector that is parallel to bond as the normal and the point along the bond that is closest to all the ring atoms as the center.
12:09:08
yitzi
Then project each ring atom onto the plane by using a vector that runs from one one the bond atoms to the ring atom in question. Finally, do the winding test.
12:15:10
yitzi
drmeister: I'll to work it a bit more, it just occurred to me that you could use the other bond atom as the center of the plane and skip finding the point closest to the ring. Its early so I could be completely off base here.
12:15:55
drmeister
One thing is the bonds will never be really close to the ring edges because of the geometry optimization.
12:16:09
drmeister
They should cut pretty much straight through the center of the ring or not at all.
12:21:05
drmeister
I'd like to declare geom:v-, geom:vdot as primops and specify that their arguments don't escape.
12:21:35
drmeister
Then we can stack allocate l and p0-l0 and avoid allocating memory for them on the heap.
12:22:19
Bike
ideally they wouldn't need to be primops for that information to be available, but to actually stack allocate i suppose they would need primopness
12:22:48
Bike
it might be simpler to define an allocate-v primop, and have v- be an allocate-v followed by an side effecting v-!
12:23:27
drmeister
Primops would be fine for things like this - vector math has just a few operations that are done over and over and over again.
12:24:25
Bike
sure, but primops are magic and it's good to keep sorcery to a minimum. it would be nice if normally defined functions could do things like return unboxed values when possible, without the programmer needing to know compiler internals
12:24:47
drmeister
Then we have the compiler warn us if we do something illegal with a dynamic-extent allocated variable - illegal like pass it to a non-primop function where it could escape.
12:25:52
Bike
we already have a bit of tracking of function dx behavior, for the sake of calls. it shouldn't be that hard to make it work for non functions, i think
12:31:50
drmeister
Returning and passing unboxed values to functions - we'd have to overhaul the calling convention.
12:38:34
Bike
instead of a primop, we define a compiler transform on v- so when the compiler sees a call to it, and the result of the call is DX, it replaces the call by an allocate v-! sequence
12:39:31
Bike
of course cleavir doesn't actually track DX like that right now, but it shouldn't be too hard to make it do so
12:39:55
Bike
and if it's told that vdot doesn't extend the extent of its arguments, even the dynamic-extent declaration shouldn't be necessary
12:40:35
drmeister
I have put off writing a lot of this kind of code because I knew it would run like shit.
12:41:49
drmeister
If I knew I could write efficient code that won't break in the future I would be off to the races.
12:42:29
drmeister
Add the define-primop thing first and then deal with the DX stuff if that is a logical path.
12:44:30
Bike
i'm gonna do the define-primop thing, and then another compiler thing that should make unboxed array access possible, and then i think i can get doing the dx stuff
12:46:16
Bike
the other thing with DX is that there's kind of an inherent safety problem, in that if you redefine vdot later so that its arguments escape, problems will happen and there's not really a way to defend against it
12:47:44
Bike
tangential but i could also look at using llvm vector arithmetic for vec3s, if you're not doing that already
12:55:48
drmeister
Use :double-float rather than :double ... And :single-float rather than :float for specifying types in primitives.
12:57:21
drmeister
Look at what I've done to primitives.lsp. We don't store thread local types in the PRIMITIVE struct anymore - it's all symbols.
12:57:48
Bike
i'm not sure about some of the ffi stuff. i reused the to_object_float/double we have for those, but i defined new intrinsics for unboxing, since ffi's does coercions we don't need or want in the compiler
12:57:56
drmeister
cmp:*PRIMITIVES* is a thread-safe EQUAL hash table that maps strings to PRIMITIVE structs that contain everything you need to generate a primitive.
12:59:35
drmeister
Yeah. I have a really, really good feeling about all of this. I think we are going to see some big performance enhancement.
13:01:34
drmeister
I've been building cando and running within the jupyterlab environment. Everything is working.
13:52:58
drmeister
https://github.com/clasp-developers/clasp/blob/unboxed-floats/src/llvmo/llvmoExpose.cc#L4438
13:53:23
drmeister
This is how I fixed the problem: else if (S.getProtectionFlags() & llvm::sys::Memory::MF_EXEC)
13:54:36
drmeister
llvm13 has gone off the rails with object file section names and now it's brittle to use the names to recognized "text" sections. Lang said use page protection flags and so that's what I'm doing now.
14:50:44
drmeister
I may have built and then made what I thought were trivial last minute changes and then pushed.
14:54:23
Bike
https://github.com/clasp-developers/clasp/blob/unboxed-floats/src/lisp/kernel/cmp/primitives.lsp#L456
14:55:09
Bike
while it's trying to construct an intrinsic's function type, i think, but the backtrace is kind of bad because of all the evaluator frames
14:56:36
Bike
if you're not seeing this i might have just messed up a merge, but it looked like it was fine so i dunono
14:59:05
drmeister
I think it's a merge issue on your end. But I'll stop messing around with this code now and work on other things. I don't want to mess you up.
14:59:49
drmeister
Feel free to take out the (format t "Defining primitive: ~a~%" name) from the define-primitive function.
15:11:09
drmeister
For example, I'm adding Atom_O::getPosition_BANG_(Vector3& pos) { pos = this->position; };
15:12:09
drmeister
Then in Cando code I'll use (let ((pos (geom:vec 0 0 0))) (declare (dynamic-extent pos)) (chem:do-atoms (atm molecule) (chem:get-position! pos atm) ...))
15:41:05
yitzi
drmeister: I worked out the logic on my ring test idea. Sent via gchat. I haven't tried to implement it yet.