simplify Target::GenericParam

compiler/rustc_attr_ir/src/target.rs

@@ -6,13 +6,6 @@ pub use rustc_ast::visit::AssocCtxt;
 use rustc_ast::{AssocItemKind, ForeignItemKind, ast};
 use rustc_macros::StableHash;
 
-#[derive(Copy, Clone, PartialEq, Debug, Eq, StableHash)]
-pub enum GenericParamKind {
-    Type,
-    Lifetime,
-    Const,
-}
-
 #[derive(Copy, Clone, PartialEq, Debug, Eq, StableHash)]
 pub enum MethodKind {
     /// Method in a `trait Trait` block
@@ -55,7 +48,9 @@ pub enum Target {
     ForeignFn,
     ForeignStatic,
     ForeignTy,
-    GenericParam { kind: GenericParamKind, has_default: bool },
+    LifetimeParam,
+    TypeParam,
+    ConstParam,
     MacroDef,
     Param,
     PatField,
@@ -106,7 +101,9 @@ impl Target {
             | Target::ForeignFn
             | Target::ForeignStatic
             | Target::ForeignTy
-            | Target::GenericParam { .. }
+            | Target::TypeParam
+            | Target::LifetimeParam
+            | Target::ConstParam
             | Target::MacroDef
             | Target::Param
             | Target::PatField
@@ -222,11 +219,9 @@ impl Target {
             Target::ForeignFn => "foreign function",
             Target::ForeignStatic => "foreign static item",
             Target::ForeignTy => "foreign type",
-            Target::GenericParam { kind, .. } => match kind {
-                GenericParamKind::Type => "type parameter",
-                GenericParamKind::Lifetime => "lifetime parameter",
-                GenericParamKind::Const => "const parameter",
-            },
+            Target::TypeParam => "type parameter",
+            Target::LifetimeParam => "lifetime parameter",
+            Target::ConstParam => "const parameter",
             Target::MacroDef => "macro def",
             Target::Param => "function param",
             Target::PatField => "pattern field",
@@ -277,11 +272,9 @@ impl Target {
             Target::ForeignFn => "foreign functions",
             Target::ForeignStatic => "foreign statics",
             Target::ForeignTy => "foreign types",
-            Target::GenericParam { kind, has_default: _ } => match kind {
-                GenericParamKind::Type => "type parameters",
-                GenericParamKind::Lifetime => "lifetime parameters",
-                GenericParamKind::Const => "const parameters",
-            },
+            Target::TypeParam => "type parameters",
+            Target::LifetimeParam => "lifetime parameters",
+            Target::ConstParam => "const parameters",
             Target::MacroDef => "macro defs",
             Target::Param => "function params",
             Target::PatField => "pattern fields",

compiler/rustc_attr_parsing/src/attributes/rustc_internal.rs

@@ -2,7 +2,6 @@ use std::path::PathBuf;
 
 use rustc_ast::{LitIntType, LitKind, MetaItemLit};
 use rustc_attr_ir::lang_items::LangItem;
-use rustc_attr_ir::target::GenericParamKind;
 use rustc_attr_ir::{
     BorrowckGraphvizFormatKind, CguFields, CguKind, RustcCleanAttribute, RustcCleanQueries,
     RustcMirKind,
@@ -109,10 +108,8 @@ pub(crate) struct RustcPanicsWhenZeroParser;
 
 impl NoArgsAttributeParser for RustcPanicsWhenZeroParser {
     const PATH: &[Symbol] = &[sym::rustc_panics_when_zero];
-    const ALLOWED_TARGETS: AllowedTargets<'_> = AllowedTargets::AllowList(&[
-        Allow(Target::GenericParam { kind: GenericParamKind::Const, has_default: true }),
-        Allow(Target::GenericParam { kind: GenericParamKind::Const, has_default: false }),
-    ]);
+    const ALLOWED_TARGETS: AllowedTargets<'_> =
+        AllowedTargets::AllowList(&[Allow(Target::ConstParam)]);
     const STABILITY: AttributeStability = unstable!(rustc_attrs);
 
     const CREATE: fn(Span) -> AttributeKind = |_| AttributeKind::RustcPanicsWhenZero;

compiler/rustc_attr_parsing/src/attributes/semantics.rs

@@ -1,17 +1,12 @@
-use rustc_attr_ir::target::GenericParamKind;
 use rustc_feature::AttributeStability;
 
 use super::prelude::*;
 
 pub(crate) struct MayDangleParser;
 impl NoArgsAttributeParser for MayDangleParser {
     const PATH: &[Symbol] = &[sym::may_dangle];
-    const ALLOWED_TARGETS: AllowedTargets<'_> = AllowedTargets::AllowList(&[
-        Allow(Target::GenericParam { kind: GenericParamKind::Type, has_default: false }),
-        Allow(Target::GenericParam { kind: GenericParamKind::Type, has_default: true }),
-        Allow(Target::GenericParam { kind: GenericParamKind::Lifetime, has_default: false }),
-        Allow(Target::GenericParam { kind: GenericParamKind::Lifetime, has_default: true }),
-    ]);
+    const ALLOWED_TARGETS: AllowedTargets<'_> =
+        AllowedTargets::AllowList(&[Allow(Target::TypeParam), Allow(Target::LifetimeParam)]);
     const STABILITY: AttributeStability = unstable!(dropck_eyepatch);
     const CREATE: fn(span: Span) -> AttributeKind = AttributeKind::MayDangle;
 }

compiler/rustc_attr_parsing/src/attributes/stability.rs

@@ -1,6 +1,6 @@
 use std::num::NonZero;
 
-use rustc_attr_ir::target::{AssocCtxt, GenericParamKind, MethodKind, Target};
+use rustc_attr_ir::target::{AssocCtxt, MethodKind, Target};
 use rustc_attr_ir::{
     DefaultBodyStability, PartialConstStability, Stability, StabilityLevel, StableSince,
     UnstableReason, UnstableRemovedFeature, VERSION_PLACEHOLDER,
@@ -40,7 +40,7 @@ const ALLOWED_TARGETS: AllowedTargets<'_> = AllowedTargets::AllowList(&[
     Allow(Target::TyAlias),
     Allow(Target::Variant),
     Allow(Target::Field),
-    Allow(Target::GenericParam { kind: GenericParamKind::Type, has_default: true }),
+    Allow(Target::TypeParam),
     Allow(Target::Static),
     Allow(Target::ForeignFn),
     Allow(Target::ForeignStatic),

compiler/rustc_attr_parsing/src/target_checking.rs

@@ -532,30 +532,9 @@ pub(crate) const ALL_TARGETS: &[Policy] = {
         Allow(Target::Crate),
         Allow(Target::Delegation { mac: false }),
         Allow(Target::Delegation { mac: true }),
-        Allow(Target::GenericParam {
-            kind: rustc_attr_ir::target::GenericParamKind::Const,
-            has_default: false,
-        }),
-        Allow(Target::GenericParam {
-            kind: rustc_attr_ir::target::GenericParamKind::Const,
-            has_default: true,
-        }),
-        Allow(Target::GenericParam {
-            kind: rustc_attr_ir::target::GenericParamKind::Lifetime,
-            has_default: false,
-        }),
-        Allow(Target::GenericParam {
-            kind: rustc_attr_ir::target::GenericParamKind::Lifetime,
-            has_default: true,
-        }),
-        Allow(Target::GenericParam {
-            kind: rustc_attr_ir::target::GenericParamKind::Type,
-            has_default: false,
-        }),
-        Allow(Target::GenericParam {
-            kind: rustc_attr_ir::target::GenericParamKind::Type,
-            has_default: true,
-        }),
+        Allow(Target::ConstParam),
+        Allow(Target::LifetimeParam),
+        Allow(Target::TypeParam),
         Allow(Target::Loop),
         Allow(Target::ForLoop),
         Allow(Target::While),

compiler/rustc_expand/src/expand.rs

@@ -1748,22 +1748,10 @@ impl InvocationCollectorNode for ast::GenericParam {
         walk_flat_map_generic_param(collector, self)
     }
     fn as_target(&self) -> Target {
-        let mut has_default = false;
-        Target::GenericParam {
-            kind: match &self.kind {
-                rustc_ast::GenericParamKind::Lifetime => {
-                    rustc_attr_ir::target::GenericParamKind::Lifetime
-                }
-                rustc_ast::GenericParamKind::Type { default } => {
-                    has_default = default.is_some();
-                    rustc_attr_ir::target::GenericParamKind::Type
-                }
-                rustc_ast::GenericParamKind::Const { default, .. } => {
-                    has_default = default.is_some();
-                    rustc_attr_ir::target::GenericParamKind::Const
-                }
-            },
-            has_default,
+        match self.kind {
+            rustc_ast::GenericParamKind::Lifetime => Target::LifetimeParam,
+            rustc_ast::GenericParamKind::Type { .. } => Target::TypeParam,
+            rustc_ast::GenericParamKind::Const { .. } => Target::ConstParam,
         }
     }
 }

compiler/rustc_hir/src/target_impls.rs

@@ -1,6 +1,6 @@
 //! Implements conversions from HIR types to Target.
 
-use rustc_attr_ir::target::{AssocCtxt, GenericParamKind, MethodKind, Target};
+use rustc_attr_ir::target::{AssocCtxt, MethodKind, Target};
 
 use crate::def::DefKind;
 use crate::{self as hir, ItemKind, TraitItemKind};
@@ -18,17 +18,9 @@ impl From<&hir::ForeignItem<'_>> for Target {
 impl From<&hir::GenericParam<'_>> for Target {
     fn from(generic_param: &hir::GenericParam<'_>) -> Target {
         match generic_param.kind {
-            hir::GenericParamKind::Type { default, .. } => Target::GenericParam {
-                kind: GenericParamKind::Type,
-                has_default: default.is_some(),
-            },
-            hir::GenericParamKind::Lifetime { .. } => {
-                Target::GenericParam { kind: GenericParamKind::Lifetime, has_default: false }
-            }
-            hir::GenericParamKind::Const { default, .. } => Target::GenericParam {
-                kind: GenericParamKind::Const,
-                has_default: default.is_some(),
-            },
+            hir::GenericParamKind::Type { .. } => Target::TypeParam,
+            hir::GenericParamKind::Lifetime { .. } => Target::LifetimeParam,
+            hir::GenericParamKind::Const { .. } => Target::ConstParam,
         }
     }
 }

compiler/rustc_passes/src/check_attr.rs

@@ -872,7 +872,9 @@ impl<'tcx> CheckAttrVisitor<'tcx> {
             | Target::ForeignFn
             | Target::ForeignStatic
             | Target::ForeignTy
-            | Target::GenericParam { .. }
+            | Target::TypeParam
+            | Target::LifetimeParam
+            | Target::ConstParam
             | Target::MacroDef
             | Target::PatField
             | Target::ExprField