`TraceEvent <-> u32` conversion is overlapping and lossy

[mooori]

For example, if code in AssertionFailed(code) happens to be 0xfc it is converted to 0xfc, same as FrameEnd. There seems to be no restriction on the values that code can take.

miden-debug/crates/engine/src/exec/trace_event.rs

Lines 34 to 42 in e1cfe13

	pub fn as_u32(self) -> u32 {
	match self {
	Self::FrameStart => TRACE_FRAME_START,
	Self::FrameEnd => TRACE_FRAME_END,
	Self::AssertionFailed(None) => 0,
	Self::AssertionFailed(Some(code)) => code.get(),
	Self::Unknown(event) => event,
	}
	}

Not all TraceEvent variants can be constructed from u32:

miden-debug/crates/engine/src/exec/trace_event.rs

Lines 44 to 52 in e1cfe13

	impl From<u32> for TraceEvent {
	fn from(raw: u32) -> Self {
	match raw {
	TRACE_FRAME_START => Self::FrameStart,
	TRACE_FRAME_END => Self::FrameEnd,
	_ => Self::Unknown(raw),
	}
	}
	}

Impact

Might not cause any issues as assertion failures are handled separately. However TraceEvent and the conversion methods are public and hitting that issue would cause confusion.