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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-06-07 05:48:48 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-06-07 05:48:48 +0000
commitef24de24a82fe681581cc130f342363c47c0969a (patch)
tree0d494f7e1a38b95c92426f58fe6eaa877303a86c /compiler/rustc_data_structures/src/functor.rs
parentReleasing progress-linux version 1.74.1+dfsg1-1~progress7.99u1. (diff)
downloadrustc-ef24de24a82fe681581cc130f342363c47c0969a.tar.xz
rustc-ef24de24a82fe681581cc130f342363c47c0969a.zip
Merging upstream version 1.75.0+dfsg1.
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'compiler/rustc_data_structures/src/functor.rs')
-rw-r--r--compiler/rustc_data_structures/src/functor.rs116
1 files changed, 0 insertions, 116 deletions
diff --git a/compiler/rustc_data_structures/src/functor.rs b/compiler/rustc_data_structures/src/functor.rs
deleted file mode 100644
index e3fcaccb1..000000000
--- a/compiler/rustc_data_structures/src/functor.rs
+++ /dev/null
@@ -1,116 +0,0 @@
-use rustc_index::{Idx, IndexVec};
-use std::{mem, rc::Rc, sync::Arc};
-
-pub trait IdFunctor: Sized {
- type Inner;
-
- fn try_map_id<F, E>(self, f: F) -> Result<Self, E>
- where
- F: FnMut(Self::Inner) -> Result<Self::Inner, E>;
-}
-
-impl<T> IdFunctor for Box<T> {
- type Inner = T;
-
- #[inline]
- fn try_map_id<F, E>(self, mut f: F) -> Result<Self, E>
- where
- F: FnMut(Self::Inner) -> Result<Self::Inner, E>,
- {
- let raw = Box::into_raw(self);
- Ok(unsafe {
- // SAFETY: The raw pointer points to a valid value of type `T`.
- let value = raw.read();
- // SAFETY: Converts `Box<T>` to `Box<MaybeUninit<T>>` which is the
- // inverse of `Box::assume_init()` and should be safe.
- let raw: Box<mem::MaybeUninit<T>> = Box::from_raw(raw.cast());
- // SAFETY: Write the mapped value back into the `Box`.
- Box::write(raw, f(value)?)
- })
- }
-}
-
-impl<T> IdFunctor for Vec<T> {
- type Inner = T;
-
- #[inline]
- fn try_map_id<F, E>(self, f: F) -> Result<Self, E>
- where
- F: FnMut(Self::Inner) -> Result<Self::Inner, E>,
- {
- self.into_iter().map(f).collect()
- }
-}
-
-impl<T> IdFunctor for Box<[T]> {
- type Inner = T;
-
- #[inline]
- fn try_map_id<F, E>(self, f: F) -> Result<Self, E>
- where
- F: FnMut(Self::Inner) -> Result<Self::Inner, E>,
- {
- Vec::from(self).try_map_id(f).map(Into::into)
- }
-}
-
-impl<I: Idx, T> IdFunctor for IndexVec<I, T> {
- type Inner = T;
-
- #[inline]
- fn try_map_id<F, E>(self, f: F) -> Result<Self, E>
- where
- F: FnMut(Self::Inner) -> Result<Self::Inner, E>,
- {
- self.raw.try_map_id(f).map(IndexVec::from_raw)
- }
-}
-
-macro_rules! rc {
- ($($rc:ident),+) => {$(
- impl<T: Clone> IdFunctor for $rc<T> {
- type Inner = T;
-
- #[inline]
- fn try_map_id<F, E>(mut self, mut f: F) -> Result<Self, E>
- where
- F: FnMut(Self::Inner) -> Result<Self::Inner, E>,
- {
- // We merely want to replace the contained `T`, if at all possible,
- // so that we don't needlessly allocate a new `$rc` or indeed clone
- // the contained type.
- unsafe {
- // First step is to ensure that we have a unique reference to
- // the contained type, which `$rc::make_mut` will accomplish (by
- // allocating a new `$rc` and cloning the `T` only if required).
- // This is done *before* casting to `$rc<ManuallyDrop<T>>` so that
- // panicking during `make_mut` does not leak the `T`.
- $rc::make_mut(&mut self);
-
- // Casting to `$rc<ManuallyDrop<T>>` is safe because `ManuallyDrop`
- // is `repr(transparent)`.
- let ptr = $rc::into_raw(self).cast::<mem::ManuallyDrop<T>>();
- let mut unique = $rc::from_raw(ptr);
-
- // Call to `$rc::make_mut` above guarantees that `unique` is the
- // sole reference to the contained value, so we can avoid doing
- // a checked `get_mut` here.
- let slot = $rc::get_mut_unchecked(&mut unique);
-
- // Semantically move the contained type out from `unique`, fold
- // it, then move the folded value back into `unique`. Should
- // folding fail, `ManuallyDrop` ensures that the "moved-out"
- // value is not re-dropped.
- let owned = mem::ManuallyDrop::take(slot);
- let folded = f(owned)?;
- *slot = mem::ManuallyDrop::new(folded);
-
- // Cast back to `$rc<T>`.
- Ok($rc::from_raw($rc::into_raw(unique).cast()))
- }
- }
- }
- )+};
-}
-
-rc! { Rc, Arc }