Tune the inlinability of Result::unwrap

This commit is contained in:
Scott McMurray 2024-01-11 21:20:15 -08:00
parent 62d7ed4a67
commit b858c591dd
2 changed files with 27 additions and 1 deletions

View File

@ -1061,7 +1061,7 @@ impl<T, E> Result<T, E> {
/// let x: Result<u32, &str> = Err("emergency failure");
/// x.unwrap(); // panics with `emergency failure`
/// ```
#[inline]
#[inline(always)]
#[track_caller]
#[stable(feature = "rust1", since = "1.0.0")]
pub fn unwrap(self) -> T

View File

@ -0,0 +1,26 @@
// compile-flags: -C opt-level=z --edition=2021
// ignore-debug
#![crate_type = "lib"]
// From <https://github.com/rust-lang/rust/issues/115463>
// CHECK-LABEL: @read_up_to_8(
#[no_mangle]
pub fn read_up_to_8(buf: &[u8]) -> u64 {
// CHECK-NOT: unwrap_failed
if buf.len() < 4 {
// actual instance has more code.
return 0;
}
let lo = u32::from_le_bytes(buf[..4].try_into().unwrap()) as u64;
let hi = u32::from_le_bytes(buf[buf.len() - 4..][..4].try_into().unwrap()) as u64;
lo | (hi << 8 * (buf.len() as u64 - 4))
}
// CHECK-LABEL: @checking_unwrap_expectation(
#[no_mangle]
pub fn checking_unwrap_expectation(buf: &[u8]) -> &[u8; 4] {
// CHECK: call void @_ZN4core6result13unwrap_failed17h
buf.try_into().unwrap()
}