This PR does two things:
- Fixes some scoping issues in Z# having to do with the context in which function and struct definitions are interpreted.
- Improves speed and reduces TermTable memory consumption by 2x (by keying on Arc<TermData> rather than TermData)
- Improves speed for Z# array handling with a BTreeMap -> HashMap swap
- Adds intrinsic widening casts in Z#. These were previously handled by bit-splitting, which is wasteful.
On array-heavy Z# programs, this PR improves speed by about 5x and memory consumption by roughly the same.
---
* zsharp::term::ir_array should use HashMap (faster, less memory)
* perf improvements
constant folding: get rid of redundant clones
bitvector: impl arith for refs
TermTable: don't store redundant term as key
* EMBED widening casts
* generic inf: need to push fn defn context onto filestack
* canonicalize path in err msg
* need struct defn on filestack, too
* no need to warn about U32 indexing in zsharp
* fix warning
50b97f6acb