Rollup merge of #107533 - pnkfelix:distinguish-generator-state-in-print-type-sizes, r=compiler-errors
Extend `-Z print-type-sizes` to distinguish generator upvars+locals from "normal" fields.
For example, for this code:
```rust
async fn wait() {}
async fn test(arg: [u8; 8192]) {
wait().await;
drop(arg);
}
async fn test_ideal(_rg: [u8; 8192]) {
wait().await;
// drop(arg);
}
fn main() {
let gen_t = test([0; 8192]);
let gen_i = test_ideal([0; 8192]);
println!("expect {}, got: {}",
std::mem::size_of_val(&gen_i),
std::mem::size_of_val(&gen_t));
}
```
the `-Z print-type-sizes` output used to start with:
```
print-type-size type: `[async fn body@issue-62958-a.rs:3:32: 6:2]`: 16386 bytes, alignment: 1 bytes
print-type-size discriminant: 1 bytes
print-type-size variant `Suspend0`: 16385 bytes
print-type-size field `.arg`: 8192 bytes, offset: 0 bytes, alignment: 1 bytes
print-type-size field `.arg`: 8192 bytes
print-type-size field `.__awaitee`: 1 bytes
...
print-type-size type: `std::mem::ManuallyDrop<[u8; 8192]>`: 8192 bytes, alignment: 1 bytes
print-type-size field `.value`: 8192 bytes
...
```
but with this change, it now instead prints:
```
print-type-size type: `[async fn body@issue-62958-a.rs:3:32: 6:2]`: 16386 bytes, alignment: 1 bytes
print-type-size discriminant: 1 bytes
print-type-size variant `Suspend0`: 16385 bytes
print-type-size upvar `.arg`: 8192 bytes, offset: 0 bytes, alignment: 1 bytes
print-type-size local `.arg`: 8192 bytes
print-type-size local `.__awaitee`: 1 bytes
...
print-type-size type: `std::mem::ManuallyDrop<[u8; 8192]>`: 8192 bytes, alignment: 1 bytes
print-type-size field `.value`: 8192 bytes
```
(spawned off of investigation of https://github.com/rust-lang/rust/issues/62958 )