| Issue |
115751
|
| Summary |
Failure to infer that `ctpop(y) == 1` implies `y != 0`
|
| Labels |
missed-optimization
|
| Assignees |
|
| Reporter |
Kmeakin
|
If `y.is_power_of_two()` is `true`, then `y` cannot be `0`, so the `panic` branch should be eliminated
```rust
#[no_mangle]
pub fn src1(x: u32, y: u32) -> u32 {
if y.is_power_of_two() {
x / y
} else {
0
}
}
#[no_mangle]
pub fn tgt1(x: u32, y: u32) -> u32 {
if y.is_power_of_two() {
x >> y.trailing_zeros()
} else {
0
}
}
#[no_mangle]
pub fn src2(x: u32, y: u32) -> u32 {
if y.is_power_of_two() {
x % y
} else {
0
}
}
#[no_mangle]
pub fn tgt2(x: u32, y: u32) -> u32 {
if y.is_power_of_two() {
x & (y - 1)
} else {
0
}
}
```
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