Merge pull request rust-lang#18475 from Veykril/push-zkvkpxttozup

Support new #[rustc_intrinsic] attribute and fallback bodies

Author: Veykril

src/tools/rust-analyzer/crates/hir-def/src/data.rs

@@ -13,7 +13,6 @@ use syntax::{ast, Parse};
 use triomphe::Arc;
 
 use crate::{
-    attr::Attrs,
     db::DefDatabase,
     expander::{Expander, Mark},
     item_tree::{self, AssocItem, FnFlags, ItemTree, ItemTreeId, MacroCall, ModItem, TreeId},
@@ -37,8 +36,6 @@ pub struct FunctionData {
     pub name: Name,
     pub params: Box<[TypeRefId]>,
     pub ret_type: TypeRefId,
-    // FIXME: why are these stored here? They should be accessed via the query
-    pub attrs: Attrs,
     pub visibility: RawVisibility,
     pub abi: Option<Symbol>,
     pub legacy_const_generics_indices: Option<Box<Box<[u32]>>>,
@@ -115,7 +112,6 @@ impl FunctionData {
                 .filter_map(|(_, param)| param.type_ref)
                 .collect(),
             ret_type: func.ret_type,
-            attrs: item_tree.attrs(db, krate, ModItem::from(loc.id.value).into()),
             visibility,
             abi: func.abi.clone(),
             legacy_const_generics_indices,

src/tools/rust-analyzer/crates/hir-expand/src/inert_attr_macro.rs

@@ -632,6 +632,19 @@ pub const INERT_ATTRIBUTES: &[BuiltinAttribute] = &[
         rustc_safe_intrinsic, Normal, template!(Word), WarnFollowing,
         "the `#[rustc_safe_intrinsic]` attribute is used internally to mark intrinsics as safe"
     ),
+    rustc_attr!(
+        rustc_intrinsic, Normal, template!(Word), ErrorFollowing,
+        "the `#[rustc_intrinsic]` attribute is used to declare intrinsics with function bodies",
+    ),
+    rustc_attr!(
+        rustc_no_mir_inline, Normal, template!(Word), WarnFollowing,
+        "#[rustc_no_mir_inline] prevents the MIR inliner from inlining a function while not affecting codegen"
+    ),
+    rustc_attr!(
+        rustc_intrinsic_must_be_overridden, Normal, template!(Word), ErrorFollowing,
+        "the `#[rustc_intrinsic_must_be_overridden]` attribute is used to declare intrinsics without real bodies",
+    ),
+
     rustc_attr!(
         rustc_deprecated_safe_2024, Normal, template!(Word), WarnFollowing,
         "the `#[rustc_safe_intrinsic]` marks functions as unsafe in Rust 2024",

src/tools/rust-analyzer/crates/hir-ty/src/consteval/tests/intrinsics.rs

@@ -4,9 +4,8 @@ use super::*;
 fn size_of() {
     check_number(
         r#"
-        extern "rust-intrinsic" {
-            pub fn size_of<T>() -> usize;
-        }
+        #[rustc_intrinsic]
+        pub fn size_of<T>() -> usize;
 
         const GOAL: usize = size_of::<i32>();
         "#,
@@ -19,9 +18,8 @@ fn size_of_val() {
     check_number(
         r#"
         //- minicore: coerce_unsized
-        extern "rust-intrinsic" {
-            pub fn size_of_val<T: ?Sized>(_: *const T) -> usize;
-        }
+        #[rustc_intrinsic]
+        pub fn size_of_val<T: ?Sized>(_: *const T) -> usize;
 
         struct X(i32, u8);
 
@@ -32,9 +30,8 @@ fn size_of_val() {
     check_number(
         r#"
         //- minicore: coerce_unsized
-        extern "rust-intrinsic" {
-            pub fn size_of_val<T: ?Sized>(_: *const T) -> usize;
-        }
+        #[rustc_intrinsic]
+        pub fn size_of_val<T: ?Sized>(_: *const T) -> usize;
 
         const GOAL: usize = {
             let it: &[i32] = &[1, 2, 3];
@@ -48,9 +45,8 @@ fn size_of_val() {
         //- minicore: coerce_unsized, transmute
         use core::mem::transmute;
 
-        extern "rust-intrinsic" {
-            pub fn size_of_val<T: ?Sized>(_: *const T) -> usize;
-        }
+        #[rustc_intrinsic]
+        pub fn size_of_val<T: ?Sized>(_: *const T) -> usize;
 
         struct X {
             x: i64,
@@ -70,9 +66,8 @@ fn size_of_val() {
         //- minicore: coerce_unsized, transmute
         use core::mem::transmute;
 
-        extern "rust-intrinsic" {
-            pub fn size_of_val<T: ?Sized>(_: *const T) -> usize;
-        }
+        #[rustc_intrinsic]
+        pub fn size_of_val<T: ?Sized>(_: *const T) -> usize;
 
         struct X {
             x: i32,
@@ -90,9 +85,8 @@ fn size_of_val() {
     check_number(
         r#"
         //- minicore: coerce_unsized, fmt, builtin_impls, dispatch_from_dyn
-        extern "rust-intrinsic" {
-            pub fn size_of_val<T: ?Sized>(_: *const T) -> usize;
-        }
+        #[rustc_intrinsic]
+        pub fn size_of_val<T: ?Sized>(_: *const T) -> usize;
 
         const GOAL: usize = {
             let x: &i16 = &5;
@@ -106,9 +100,8 @@ fn size_of_val() {
     check_number(
         r#"
         //- minicore: coerce_unsized
-        extern "rust-intrinsic" {
-            pub fn size_of_val<T: ?Sized>(_: *const T) -> usize;
-        }
+        #[rustc_intrinsic]
+        pub fn size_of_val<T: ?Sized>(_: *const T) -> usize;
 
         const GOAL: usize = {
             size_of_val("salam")
@@ -123,9 +116,8 @@ fn min_align_of_val() {
     check_number(
         r#"
         //- minicore: coerce_unsized
-        extern "rust-intrinsic" {
-            pub fn min_align_of_val<T: ?Sized>(_: *const T) -> usize;
-        }
+        #[rustc_intrinsic]
+        pub fn min_align_of_val<T: ?Sized>(_: *const T) -> usize;
 
         struct X(i32, u8);
 
@@ -136,9 +128,8 @@ fn min_align_of_val() {
     check_number(
         r#"
         //- minicore: coerce_unsized
-        extern "rust-intrinsic" {
-            pub fn min_align_of_val<T: ?Sized>(_: *const T) -> usize;
-        }
+        #[rustc_intrinsic]
+        pub fn min_align_of_val<T: ?Sized>(_: *const T) -> usize;
 
         const GOAL: usize = {
             let x: &[i32] = &[1, 2, 3];
@@ -153,19 +144,17 @@ fn min_align_of_val() {
 fn type_name() {
     check_str(
         r#"
-        extern "rust-intrinsic" {
-            pub fn type_name<T: ?Sized>() -> &'static str;
-        }
+        #[rustc_intrinsic]
+        pub fn type_name<T: ?Sized>() -> &'static str;
 
         const GOAL: &str = type_name::<i32>();
         "#,
         "i32",
     );
     check_str(
         r#"
-        extern "rust-intrinsic" {
-            pub fn type_name<T: ?Sized>() -> &'static str;
-        }
+        #[rustc_intrinsic]
+        pub fn type_name<T: ?Sized>() -> &'static str;
 
         mod mod1 {
             pub mod mod2 {
@@ -183,9 +172,8 @@ fn type_name() {
 fn transmute() {
     check_number(
         r#"
-        extern "rust-intrinsic" {
-            pub fn transmute<T, U>(e: T) -> U;
-        }
+        #[rustc_intrinsic]
+        pub fn transmute<T, U>(e: T) -> U;
 
         const GOAL: i32 = transmute((1i16, 1i16));
         "#,
@@ -197,10 +185,10 @@ fn transmute() {
 fn read_via_copy() {
     check_number(
         r#"
-        extern "rust-intrinsic" {
-            pub fn read_via_copy<T>(e: *const T) -> T;
-            pub fn volatile_load<T>(e: *const T) -> T;
-        }
+        #[rustc_intrinsic]
+        pub fn read_via_copy<T>(e: *const T) -> T;
+        #[rustc_intrinsic]
+        pub fn volatile_load<T>(e: *const T) -> T;
 
         const GOAL: i32 = {
             let x = 2;
@@ -399,9 +387,14 @@ fn discriminant_value() {
 fn likely() {
     check_number(
         r#"
-        extern "rust-intrinsic" {
-            pub fn likely(b: bool) -> bool;
-            pub fn unlikely(b: bool) -> bool;
+        #[rustc_intrinsic]
+        pub const fn likely(b: bool) -> bool {
+            b
+        }
+
+        #[rustc_intrinsic]
+        pub const fn unlikely(b: bool) -> bool {
+            b
         }
 
         const GOAL: bool = likely(true) && unlikely(true) && !likely(false) && !unlikely(false);
@@ -704,9 +697,8 @@ fn rotate() {
     );
     check_number(
         r#"
-        extern "rust-intrinsic" {
-            pub fn rotate_right<T: Copy>(x: T, y: T) -> T;
-        }
+        #[rustc_intrinsic]
+        pub fn rotate_right<T: Copy>(x: T, y: T) -> T;
 
         const GOAL: i32 = rotate_right(10006016, 1020315);
         "#,
@@ -721,9 +713,8 @@ fn simd() {
         pub struct i8x16(
             i8,i8,i8,i8,i8,i8,i8,i8,i8,i8,i8,i8,i8,i8,i8,i8,
         );
-        extern "platform-intrinsic" {
-            pub fn simd_bitmask<T, U>(x: T) -> U;
-        }
+        #[rustc_intrinsic]
+        pub fn simd_bitmask<T, U>(x: T) -> U;
         const GOAL: u16 = simd_bitmask(i8x16(
             0, 1, 0, 0, 2, 255, 100, 0, 50, 0, 1, 1, 0, 0, 0, 0
         ));
@@ -735,10 +726,10 @@ fn simd() {
         pub struct i8x16(
             i8,i8,i8,i8,i8,i8,i8,i8,i8,i8,i8,i8,i8,i8,i8,i8,
         );
-        extern "platform-intrinsic" {
-            pub fn simd_lt<T, U>(x: T, y: T) -> U;
-            pub fn simd_bitmask<T, U>(x: T) -> U;
-        }
+        #[rustc_intrinsic]
+        pub fn simd_lt<T, U>(x: T, y: T) -> U;
+        #[rustc_intrinsic]
+        pub fn simd_bitmask<T, U>(x: T) -> U;
         const GOAL: u16 = simd_bitmask(simd_lt::<i8x16, i8x16>(
             i8x16(
                 -105, -4, -3, -2, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10

src/tools/rust-analyzer/crates/hir-ty/src/diagnostics/decl_check.rs

@@ -201,7 +201,7 @@ impl<'a> DeclValidator<'a> {
 
             // Don't run the lint on extern "[not Rust]" fn items with the
             // #[no_mangle] attribute.
-            let no_mangle = data.attrs.by_key(&sym::no_mangle).exists();
+            let no_mangle = self.db.attrs(func.into()).by_key(&sym::no_mangle).exists();
             if no_mangle && data.abi.as_ref().is_some_and(|abi| *abi != sym::Rust) {
                 cov_mark::hit!(extern_func_no_mangle_ignored);
             } else {