I implemented some basic array stuff today. It's boring and easy but also fast and new feature. I added a couple simple tests for it. I also want to do a code cleanup pass and did the first part of that today. The problem I'm looking to address here is that when debugging Wide functions, there's a huge amount of noise, and the functional logic is lost. This is because Wide constructors can only operate in terms of a "this" pointer, even when in reality it's just going to be loaded to produce a value right away. There were other cases when I unnecessarily promoted from value to rvalue too.
Secondly, I've got my first language feature that should throw an exception- array indexing. I'm fairly confident that LLVM can handle optimizing the array index bounds check out. Annoyingly, LLVM cannot dynamically index into an array value, which totally throws the whole value thing out of whack. Right now, I just copy to the stack every time... LLVM can optimize out the repeated copies, I'm fairly sure. I'm also going to offer an unchecked access so you can use that if the optimizer's not good enough. The problem with this is that unless I want to define the exception type in the compiler, I need my Wide Standard library available during testing, which is going to make life ... fun.
I've also been thinking about some slightly more complex transformations, like maybe yield return. Semantically, this transform is not too hard- just shift the locals that you need from allocas to member accesses, and add a member for the current "state". The trouble is that returning would implicitly mean returning an optional, which would again mean making the Wide stdlib available during testing. Another trouble is that pointers/references to the local variables can't really be trusted, but I guess this is already true of lambda captures.
I've also got to clean up stuff like attributes, introduce library is-a, and such.
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