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Dejargnonize subst

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Shoyu Vanilla 2024-02-12 15:39:32 +09:00
parent 084ce5bdb5
commit 3856df059e
128 changed files with 574 additions and 541 deletions
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8
compiler/rustc_mir_transform/src/ref_prop.rs
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@ -44,7 +44,7 @@ use crate::ssa::{SsaLocals, StorageLiveLocals};
///
/// # Liveness
///
/// When performing a substitution, we must take care not to introduce uses of dangling locals.
/// When performing an instantiation, we must take care not to introduce uses of dangling locals.
/// To ensure this, we walk the body with the `MaybeStorageDead` dataflow analysis:
/// - if we want to replace `*x` by reborrow `*y` and `y` may be dead, we allow replacement and
/// mark storage statements on `y` for removal;
@ -55,7 +55,7 @@ use crate::ssa::{SsaLocals, StorageLiveLocals};
///
/// For `&mut` borrows, we also need to preserve the uniqueness property:
/// we must avoid creating a state where we interleave uses of `*_1` and `_2`.
/// To do it, we only perform full substitution of mutable borrows:
/// To do it, we only perform full instantiation of mutable borrows:
/// we replace either all or none of the occurrences of `*_1`.
///
/// Some care has to be taken when `_1` is copied in other locals.
@ -63,10 +63,10 @@ use crate::ssa::{SsaLocals, StorageLiveLocals};
/// _3 = *_1;
/// _4 = _1
/// _5 = *_4
/// In such cases, fully substituting `_1` means fully substituting all of the copies.
/// In such cases, fully instantiating `_1` means fully instantiating all of the copies.
///
/// For immutable borrows, we do not need to preserve such uniqueness property,
/// so we perform all the possible substitutions without removing the `_1 = &_2` statement.
/// so we perform all the possible instantiations without removing the `_1 = &_2` statement.
pub struct ReferencePropagation;
impl<'tcx> MirPass<'tcx> for ReferencePropagation {