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// unit-test: InstSimplify
// compile-flags: -C panic=abort
#![crate_type = "lib"]
#![feature(core_intrinsics)]
#![feature(custom_mir)]
use std::intrinsics::mir::*;
use std::mem::{MaybeUninit, ManuallyDrop, transmute};
// EMIT_MIR combine_transmutes.identity_transmutes.InstSimplify.diff
pub unsafe fn identity_transmutes() {
// These are nops and should be removed
let _a = transmute::<i32, i32>(1);
let _a = transmute::<Vec<i32>, Vec<i32>>(Vec::new());
}
#[custom_mir(dialect = "runtime", phase = "initial")]
// EMIT_MIR combine_transmutes.integer_transmutes.InstSimplify.diff
pub unsafe fn integer_transmutes() {
mir! {
{
let A = CastTransmute::<i32, u32>(1); // Can be a cast
let B = CastTransmute::<i32, i64>(1); // UB
let C = CastTransmute::<u64, i64>(1); // Can be a cast
let D = CastTransmute::<u64, u32>(1); // UB
let E = CastTransmute::<isize, usize>(1); // Can be a cast
Return()
}
}
}
// EMIT_MIR combine_transmutes.adt_transmutes.InstSimplify.diff
pub unsafe fn adt_transmutes() {
let _a: u8 = transmute(EnumNoRepr::A);
let _a: i8 = transmute(EnumNoRepr::B);
let _a: usize = transmute(EnumReprIsize::A);
let _a: isize = transmute(EnumReprIsize::B);
let _a: u8 = transmute(std::cmp::Ordering::Less);
let _a: i8 = transmute(std::cmp::Ordering::Less);
let _a: u8 = transmute(Some(std::num::NonZeroU8::MAX));
let _a: i16 = transmute(std::num::Wrapping(0_i16));
let _a: u16 = transmute(std::num::Wrapping(0_i16));
let _a: u32 = transmute(Union32 { i32: 0 });
let _a: i32 = transmute(Union32 { u32: 0 });
let _a: ManuallyDrop<String> = transmute(MaybeUninit::<String>::uninit());
}
#[inline(always)]
#[custom_mir(dialect = "runtime", phase = "initial")]
const unsafe fn mir_transmute<T, U>(x: T) -> U {
mir!{
{
RET = CastTransmute(x);
Return()
}
}
}
pub enum EnumNoRepr { A, B, C }
#[repr(isize)]
pub enum EnumReprIsize { A, B, C }
pub union Union32 { u32: u32, i32: i32 }
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