Opcode 'stobj' not implemented error about cosmos

[mterwoord]

Sorry for the late response...

Would you be willing to help us fix this?
It's a bug in our IL interpreter..

I've also run into several "not implanted" IL errors. I'm assuming this has something to do with the recent Z-machine implantation.

[mterwoord]

Which Z-machine implementation?

The bug is in our IL interpreter, and isn't too hard to fix. We could guide you through the process....

[cuuupid]

That'd be great! Fair warning, I'm a bit lost on "IL interpreter". Is that
what interprets methods + etc into machine language?

Oh, I thought it had something to do with it. Never mind!

[mterwoord]

@phsah123 IL looks for example like this:
IL_0001: ldc.i4.3 (Loads a constant int32 value of 4 on to the stack)
IL_0002: ldc.i4.2
IL_0003: add

offset 3 ha no way of knowing (without looking back) what types it has to add (it could be 2 bytes, but also 2 decimals). The il interpreter "interprets" the previous instructions (and branches etc are also handled) to see what operand types the compiler needs to use..

The situation for stobj is not yet implemented.

[PathogenDavid]

So I decided to take a stab at this problem since I've been meaning to check out Cosmos in detail for some time and had some free time today.

Fixing Stobj for GetNumberOfStackPops and GetNumberOfStackPushes was simple enough. However, after I fixed those two things I got an issue of a missing plug for RuntimeTypeHandle::CreateInstanceForAnotherGenericParameter.

This method is called from EqualityComparer.CreateComparer when a System.Collections.Generic.Dictionary is constructed.

Of course, it might seem confusing that there is a Dictionary getting created considering pshah123's code doesn't use the Dictionary class. Well, apparently after you go over 6 cases in a switch statement on a string, the C# compiler changes it into a Dictionary lookup instead.

Anyway, I tracked down CreateInstanceForAnotherGenericParameter's implementation in CoreCLR to CreateInstanceForGenericType, and it is a bit of a doozy.

I'm pretty sure the whole thing boils down to allocating and constructing a GenericEqualityComparer (in our case), but it isn't immediately obvious to me how to best do the same thing in Cosmos. I wanted to post in here and see if anyone wanted to point me in the right direction before I dive down this rabbit hole.

[PathogenDavid]

And on a semi-related note: Is there a way to get changes I've made to Cosmos into my installed user kit without restarting Visual Studio every time? Whenever I make a change to IL2CPU, I end up closing all my instances of Visual Studio and running install.bat again. Not sure if I missed something in the documentation or the workflow there is just a bit tedious right now.

[mterwoord]

@PathogenDavid Good work. Can you send a pull request for the GetNumberOfStackPops and GetNumberOfStackPushes changes?

Most likely the CreateCompiler code uses reflection to do its magic, which won't work for sure on cosmos.
Maybe we could make special cases in EqualityComparer.CreateComparer for the main types (String, numeric types, etc)

@PathogenDavid Would you be interested in helping us out? We could really use some lower-level people. We have some humps in the compiler currently and once we're past those, we could really move forward again...

[PathogenDavid]

@mterwoord
Sure, do know though that I have no idea if stobj is working since I couldn't compile+run the code without the plug. The pull request is #77.

That is what I was thinking as well. It wouldn't be as ideal, but it certainly works. I'll give it a try sometime this week and report back.

I'm definitely interested in helping out, but I can't really promise any consistent effort on my part for the time being. My free time is a bit sporadic these days.

[mterwoord]

@PathogenDavid If you're interested in helping, please add me on skype (same handle), and I'll get you going. At first, we could use help on getting the PR's reviewed...