New MIR Pass: SsaRangePropagation
As an alternative to https://github.com/rust-lang/rust/pull/150192.
Introduces a new pass that propagates the known ranges of SSA locals.
We can know the ranges of SSA locals at some locations for the following code:
```rust
fn foo(a: u32) {
let b = a < 9;
if b {
let c = b; // c is true since b is whitin the range [1, 2)
let d = a < 8; // d is true since b whitin the range [0, 9)
}
}
```
This PR only implements a trivial range: we know one value on switch, assert, and assume.
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