rust/tests/mir-opt/gvn_copy_aggregate.all_copy_2.GVN.diff
DianQK c16c22cc9c
Simplify the canonical clone method to copy
The optimized clone method ends up as the following MIR:

```
_2 = copy ((*_1).0: i32);
_3 = copy ((*_1).1: u64);
_4 = copy ((*_1).2: [i8; 3]);
_0 = Foo { a: move _2, b: move _3, c: move _4 };
```

We can transform this to:

```
_0 = copy (*_1);
```
2024-09-14 13:30:35 +08:00

65 lines
1.5 KiB
Diff

- // MIR for `all_copy_2` before GVN
+ // MIR for `all_copy_2` after GVN
fn all_copy_2(_1: &&AllCopy) -> AllCopy {
debug v => _1;
let mut _0: AllCopy;
let _2: i32;
let mut _5: i32;
let mut _6: u64;
let mut _7: [i8; 3];
let mut _8: &AllCopy;
let mut _9: &AllCopy;
let mut _10: &AllCopy;
scope 1 {
debug a => _2;
let _3: u64;
scope 2 {
debug b => _3;
let _4: [i8; 3];
scope 3 {
debug c => _4;
}
}
}
bb0: {
- StorageLive(_2);
- _8 = deref_copy (*_1);
+ nop;
+ _8 = copy (*_1);
_2 = copy ((*_8).0: i32);
- StorageLive(_3);
- _9 = deref_copy (*_1);
- _3 = copy ((*_9).1: u64);
- StorageLive(_4);
- _10 = deref_copy (*_1);
- _4 = copy ((*_10).2: [i8; 3]);
+ nop;
+ _9 = copy _8;
+ _3 = copy ((*_8).1: u64);
+ nop;
+ _10 = copy _8;
+ _4 = copy ((*_8).2: [i8; 3]);
StorageLive(_5);
_5 = copy _2;
StorageLive(_6);
_6 = copy _3;
StorageLive(_7);
_7 = copy _4;
- _0 = AllCopy { a: move _5, b: move _6, c: move _7 };
+ _0 = copy (*_8);
StorageDead(_7);
StorageDead(_6);
StorageDead(_5);
- StorageDead(_4);
- StorageDead(_3);
- StorageDead(_2);
+ nop;
+ nop;
+ nop;
return;
}
}