Module resugar

Passes that undo some lowering done by rustc to recover an operation closer to what the user wrote.

Modules

inline_local_panic_functions

panic!() expands to:

reconstruct_asserts

In the MIR AST, it seems assert are introduced to check preconditions (for the binops for example). The assert! introduced by the user introduce if ... then { panic!(...) } else { ...}. This pass introduces assert instead in order to make the code shorter.

reconstruct_boxes

Micro-pass: reconstruct piecewise box allocations using malloc and ShallowInitBox.

reconstruct_fallible_operations

Micro-pass: remove the dynamic checks for array/slice bounds, overflow, and division by zero.

reconstruct_matches

The way to match on enums in MIR is in two steps: first read the discriminant, then switch on the resulting integer. This pass merges the two into a SwitchKind::Match that directly mentions enum variants.