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properly mark tests that require panic=abort
2023-06-08 15:18:34 +08:00
// EMIT_MIR_FOR_EACH_PANIC_STRATEGY
Move SimplifyLocals before ConstProp.
2022-12-05 03:20:55 +08:00
// unit-test: SimplifyLocals-before-const-prop
Improve SimplifyLocals pass so it can remove unused consts The `ConstProp` can cause many locals to be initialized to a constant value and then never read from. `ConstProp` can also evaluate ZSTs into constant values. Previously, many of these would be removed by other parts of the MIR optimization pipeline. However, evaluating ZSTs (especially `()`) into constant values defeated those parts of the optimizer and so in a2e3ed5c054b544df6ceeb9e612d39af819f4aae, I added a hack to `ConstProp` that skips evaluating ZSTs to avoid that regression. This commit changes `SimplifyLocals` so that it doesn't consider writes of const values to a local to be a use of that local. In doing so, `SimplifyLocals` is able to remove otherwise unused locals left behind by other optimization passes (`ConstProp` in particular).
2019-10-17 18:46:51 +08:00
// compile-flags: -C overflow-checks=no
Don't print leading zeros on hex dumps constants
2020-02-05 19:17:41 +08:00
fn use_zst(_: ((), ())) {}
Improve SimplifyLocals pass so it can remove unused consts The `ConstProp` can cause many locals to be initialized to a constant value and then never read from. `ConstProp` can also evaluate ZSTs into constant values. Previously, many of these would be removed by other parts of the MIR optimization pipeline. However, evaluating ZSTs (especially `()`) into constant values defeated those parts of the optimizer and so in a2e3ed5c054b544df6ceeb9e612d39af819f4aae, I added a hack to `ConstProp` that skips evaluating ZSTs to avoid that regression. This commit changes `SimplifyLocals` so that it doesn't consider writes of const values to a local to be a use of that local. In doing so, `SimplifyLocals` is able to remove otherwise unused locals left behind by other optimization passes (`ConstProp` in particular).
2019-10-17 18:46:51 +08:00
struct Temp {
Don't print leading zeros on hex dumps constants
2020-02-05 19:17:41 +08:00
x: u8,
Improve SimplifyLocals pass so it can remove unused consts The `ConstProp` can cause many locals to be initialized to a constant value and then never read from. `ConstProp` can also evaluate ZSTs into constant values. Previously, many of these would be removed by other parts of the MIR optimization pipeline. However, evaluating ZSTs (especially `()`) into constant values defeated those parts of the optimizer and so in a2e3ed5c054b544df6ceeb9e612d39af819f4aae, I added a hack to `ConstProp` that skips evaluating ZSTs to avoid that regression. This commit changes `SimplifyLocals` so that it doesn't consider writes of const values to a local to be a use of that local. In doing so, `SimplifyLocals` is able to remove otherwise unused locals left behind by other optimization passes (`ConstProp` in particular).
2019-10-17 18:46:51 +08:00
}
Don't print leading zeros on hex dumps constants
2020-02-05 19:17:41 +08:00
fn use_u8(_: u8) {}
Improve SimplifyLocals pass so it can remove unused consts The `ConstProp` can cause many locals to be initialized to a constant value and then never read from. `ConstProp` can also evaluate ZSTs into constant values. Previously, many of these would be removed by other parts of the MIR optimization pipeline. However, evaluating ZSTs (especially `()`) into constant values defeated those parts of the optimizer and so in a2e3ed5c054b544df6ceeb9e612d39af819f4aae, I added a hack to `ConstProp` that skips evaluating ZSTs to avoid that regression. This commit changes `SimplifyLocals` so that it doesn't consider writes of const values to a local to be a use of that local. In doing so, `SimplifyLocals` is able to remove otherwise unused locals left behind by other optimization passes (`ConstProp` in particular).
2019-10-17 18:46:51 +08:00
Move SimplifyLocals before ConstProp.
2022-12-05 03:20:55 +08:00
// EMIT_MIR simplify_locals_removes_unused_consts.main.SimplifyLocals-before-const-prop.diff
Improve SimplifyLocals pass so it can remove unused consts The `ConstProp` can cause many locals to be initialized to a constant value and then never read from. `ConstProp` can also evaluate ZSTs into constant values. Previously, many of these would be removed by other parts of the MIR optimization pipeline. However, evaluating ZSTs (especially `()`) into constant values defeated those parts of the optimizer and so in a2e3ed5c054b544df6ceeb9e612d39af819f4aae, I added a hack to `ConstProp` that skips evaluating ZSTs to avoid that regression. This commit changes `SimplifyLocals` so that it doesn't consider writes of const values to a local to be a use of that local. In doing so, `SimplifyLocals` is able to remove otherwise unused locals left behind by other optimization passes (`ConstProp` in particular).
2019-10-17 18:46:51 +08:00
fn main() {
let ((), ()) = ((), ());
use_zst(((), ()));
Don't print leading zeros on hex dumps constants
2020-02-05 19:17:41 +08:00
use_u8((Temp { x: 40 }).x + 2);
Improve SimplifyLocals pass so it can remove unused consts The `ConstProp` can cause many locals to be initialized to a constant value and then never read from. `ConstProp` can also evaluate ZSTs into constant values. Previously, many of these would be removed by other parts of the MIR optimization pipeline. However, evaluating ZSTs (especially `()`) into constant values defeated those parts of the optimizer and so in a2e3ed5c054b544df6ceeb9e612d39af819f4aae, I added a hack to `ConstProp` that skips evaluating ZSTs to avoid that regression. This commit changes `SimplifyLocals` so that it doesn't consider writes of const values to a local to be a use of that local. In doing so, `SimplifyLocals` is able to remove otherwise unused locals left behind by other optimization passes (`ConstProp` in particular).
2019-10-17 18:46:51 +08:00
}