Shortform syntax for external parameter access

[UnsignedByte]

Often times when we want the existential latency for a component, we have to generate a dummy instance to do so:

Bx := new Butterfly[8, 23];
L := Bx::L

To fix this, we can have a syntax like follows:

L := Butterfly[8, 23]::L;

We also have this issue where different components cannot have any sort of relation between their existential parameters. In some cases, such as with floating point addition and subtraction components, our implementation knows the relationship between their latencies (they are equal in most cases), but existential parameters obfuscate all this information.

Ideally, we would want something like this:

comp FPSub[E, M]<'G: 1>(
   // ...
) -> (
   // ...
) with {
   some L where L == FPAdd[E, M]::L;
}

so that this information can be preserved.

[rachitnigam]

In some ways, this is not a hard change to make. We need to make Comp[Params]::Param an expression so that it can be used anywhere. One consequence of this is that the following is also a valid expression:

assert FAdd[23, 8]::L + FSub[8, 7]::T == FMul[19, 24]::E

The encoding for this is straightforward; we can just use the functions declared for each existential parameter as the expression that shows up in SMT.

Note that this is fundamentally more expressive because previously, there was no way to say that the latency of something is dependent/equal to the output parameter of something else.