port #[move_size_limit] to the new attribute parsing infrastructure

Author: jdonszelmann

compiler/rustc_attr_parsing/src/attributes/crate_level.rs

@@ -94,3 +94,29 @@ impl<S: Stage> SingleAttributeParser<S> for RecursionLimitParser {
         })
     }
 }
+
+pub(crate) struct MoveSizeLimitParser;
+
+impl<S: Stage> SingleAttributeParser<S> for MoveSizeLimitParser {
+    const PATH: &[Symbol] = &[sym::move_size_limit];
+    const ATTRIBUTE_ORDER: AttributeOrder = AttributeOrder::KeepOutermost;
+    const ON_DUPLICATE: OnDuplicate<S> = OnDuplicate::Error;
+    const TEMPLATE: AttributeTemplate = template!(NameValueStr: "N");
+
+    // FIXME: move size limit is allowed on all targets and ignored,
+    //        even though it should only be valid on crates of course
+    const ALLOWED_TARGETS: AllowedTargets = AllowedTargets::AllowList(&[Allow(Target::Crate)]);
+
+    fn convert(cx: &mut AcceptContext<'_, '_, S>, args: &ArgParser<'_>) -> Option<AttributeKind> {
+        let ArgParser::NameValue(nv) = args else {
+            cx.expected_name_value(cx.attr_span, None);
+            return None;
+        };
+
+        Some(AttributeKind::MoveSizeLimit {
+            limit: cx.parse_limit_int(nv)?,
+            attr_span: cx.attr_span,
+            limit_span: nv.value_span,
+        })
+    }
+}

compiler/rustc_attr_parsing/src/context.rs

@@ -24,7 +24,7 @@ use crate::attributes::codegen_attrs::{
     UsedParser,
 };
 use crate::attributes::confusables::ConfusablesParser;
-use crate::attributes::crate_level::{CrateNameParser, RecursionLimitParser};
+use crate::attributes::crate_level::{CrateNameParser, MoveSizeLimitParser, RecursionLimitParser};
 use crate::attributes::deprecation::DeprecationParser;
 use crate::attributes::dummy::DummyParser;
 use crate::attributes::inline::{InlineParser, RustcForceInlineParser};
@@ -181,6 +181,7 @@ attribute_parsers!(
         Single<LinkOrdinalParser>,
         Single<LinkSectionParser>,
         Single<LinkageParser>,
+        Single<MoveSizeLimitParser>,
         Single<MustUseParser>,
         Single<OptimizeParser>,
         Single<PathAttributeParser>,

compiler/rustc_hir/src/attrs/data_structures.rs

@@ -565,6 +565,9 @@ pub enum AttributeKind {
     /// Represents [`#[may_dangle]`](https://std-dev-guide.rust-lang.org/tricky/may-dangle.html).
     MayDangle(Span),
 
+    /// Represents `#[move_size_limit]`
+    MoveSizeLimit { attr_span: Span, limit_span: Span, limit: usize },
+
     /// Represents `#[must_use]`.
     MustUse {
         span: Span,

compiler/rustc_hir/src/attrs/encode_cross_crate.rs

@@ -61,6 +61,7 @@ impl AttributeKind {
             MacroUse { .. } => No,
             Marker(..) => No,
             MayDangle(..) => No,
+            MoveSizeLimit { .. } => No,
             MustUse { .. } => Yes,
             Naked(..) => No,
             NoImplicitPrelude(..) => No,

compiler/rustc_passes/src/check_attr.rs

@@ -271,6 +271,7 @@ impl<'tcx> CheckAttrVisitor<'tcx> {
                     | AttributeKind::MustUse { .. }
                     | AttributeKind::CrateName { .. }
                     | AttributeKind::RecursionLimit { .. }
+                    | AttributeKind::MoveSizeLimit { .. }
                 ) => { /* do nothing  */ }
                 Attribute::Unparsed(attr_item) => {
                     style = Some(attr_item.style);