Move visitor utils to `rustc_ast_ir`

1 files changed, 3 insertions, 65 deletions

diff --git a/compiler/rustc_ast/src/visit.rs b/compiler/rustc_ast/src/visit.rs
index f29022386a9..9efb87e53cd 100644
--- a/compiler/rustc_ast/src/visit.rs
+++ b/compiler/rustc_ast/src/visit.rs
@@ -15,11 +15,12 @@
 
 use crate::ast::*;
 
-use core::ops::ControlFlow;
-
 use rustc_span::symbol::Ident;
 use rustc_span::Span;
 
+pub use rustc_ast_ir::visit::VisitorResult;
+pub use rustc_ast_ir::{try_visit, visit_opt, walk_list, walk_visitable_list};
+
 #[derive(Copy, Clone, Debug, PartialEq)]
 pub enum AssocCtxt {
     Trait,
@@ -101,51 +102,6 @@ pub enum LifetimeCtxt {
     GenericArg,
 }
 
-/// Similar to the `Try` trait, but also implemented for `()`.
-pub trait VisitorResult {
-    type Residual;
-    fn output() -> Self;
-    fn from_residual(residual: Self::Residual) -> Self;
-    fn branch(self) -> ControlFlow<Self::Residual>;
-}
-
-impl VisitorResult for () {
-    type Residual = !;
-
-    fn output() -> Self {}
-    fn from_residual(_: !) -> Self {}
-    fn branch(self) -> ControlFlow<!> {
-        ControlFlow::Continue(())
-    }
-}
-
-impl<T> VisitorResult for ControlFlow<T> {
-    type Residual = T;
-
-    fn output() -> Self {
-        ControlFlow::Continue(())
-    }
-    fn from_residual(residual: Self::Residual) -> Self {
-        ControlFlow::Break(residual)
-    }
-    fn branch(self) -> ControlFlow<T> {
-        self
-    }
-}
-
-#[macro_export]
-macro_rules! try_visit {
-    ($e:expr) => {
-        match $crate::visit::VisitorResult::branch($e) {
-            core::ops::ControlFlow::Continue(()) => (),
-            #[allow(unreachable_code)]
-            core::ops::ControlFlow::Break(r) => {
-                return $crate::visit::VisitorResult::from_residual(r);
-            }
-        }
-    };
-}
-
 /// Each method of the `Visitor` trait is a hook to be potentially
 /// overridden. Each method's default implementation recursively visits
 /// the substructure of the input via the corresponding `walk` method;
@@ -316,24 +272,6 @@ pub trait Visitor<'ast>: Sized {
     }
 }
 
-#[macro_export]
-macro_rules! walk_list {
-    ($visitor: expr, $method: ident, $list: expr $(, $($extra_args: expr),* )?) => {
-        for elem in $list {
-            $crate::try_visit!($visitor.$method(elem $(, $($extra_args,)* )?));
-        }
-    }
-}
-
-#[macro_export]
-macro_rules! visit_opt {
-    ($visitor: expr, $method: ident, $opt: expr $(, $($extra_args: expr),* )?) => {
-        if let Some(x) = $opt {
-            $crate::try_visit!($visitor.$method(x $(, $($extra_args,)* )?));
-        }
-    }
-}
-
 pub fn walk_crate<'a, V: Visitor<'a>>(visitor: &mut V, krate: &'a Crate) -> V::Result {
     walk_list!(visitor, visit_item, &krate.items);
     walk_list!(visitor, visit_attribute, &krate.attrs);