Rollup of 4 pull requests

compiler/rustc_ast/src/attr/mod.rs

@@ -235,6 +235,34 @@ impl AttributeExt for Attribute {
         }
     }
 
+    fn deprecation_note(&self) -> Option<Symbol> {
+        match &self.kind {
+            AttrKind::Normal(normal) if normal.item.path == sym::deprecated => {
+                let meta = &normal.item;
+
+                // #[deprecated = "..."]
+                if let Some(s) = meta.value_str() {
+                    return Some(s);
+                }
+
+                // #[deprecated(note = "...")]
+                if let Some(list) = meta.meta_item_list() {
+                    for nested in list {
+                        if let Some(mi) = nested.meta_item()
+                            && mi.path == sym::note
+                            && let Some(s) = mi.value_str()
+                        {
+                            return Some(s);
+                        }
+                    }
+                }
+
+                None
+            }
+            _ => None,
+        }
+    }
+
     fn doc_resolution_scope(&self) -> Option<AttrStyle> {
         match &self.kind {
             AttrKind::DocComment(..) => Some(self.style),
@@ -277,6 +305,7 @@ impl Attribute {
 
     pub fn may_have_doc_links(&self) -> bool {
         self.doc_str().is_some_and(|s| comments::may_have_doc_links(s.as_str()))
+            || self.deprecation_note().is_some_and(|s| comments::may_have_doc_links(s.as_str()))
     }
 
     /// Extracts the MetaItem from inside this Attribute.
@@ -873,6 +902,11 @@ pub trait AttributeExt: Debug {
     /// * `#[doc(...)]` returns `None`.
     fn doc_str(&self) -> Option<Symbol>;
 
+    /// Returns the deprecation note if this is deprecation attribute.
+    /// * `#[deprecated = "note"]` returns `Some("note")`.
+    /// * `#[deprecated(note = "note", ...)]` returns `Some("note")`.
+    fn deprecation_note(&self) -> Option<Symbol>;
+
     fn is_proc_macro_attr(&self) -> bool {
         [sym::proc_macro, sym::proc_macro_attribute, sym::proc_macro_derive]
             .iter()

compiler/rustc_codegen_llvm/messages.ftl

@@ -1,4 +1,7 @@
-codegen_llvm_autodiff_component_unavailable = failed to load our autodiff backend. Did you install it via rustup?
+codegen_llvm_autodiff_component_missing = autodiff backend not found in the sysroot: {$err}
+    .note = it will be distributed via rustup in the future
+
+codegen_llvm_autodiff_component_unavailable = failed to load our autodiff backend: {$err}
 
 codegen_llvm_autodiff_without_enable = using the autodiff feature requires -Z autodiff=Enable
 codegen_llvm_autodiff_without_lto = using the autodiff feature requires setting `lto="fat"` in your Cargo.toml

compiler/rustc_codegen_llvm/src/errors.rs

@@ -34,7 +34,16 @@ impl<G: EmissionGuarantee> Diagnostic<'_, G> for ParseTargetMachineConfig<'_> {
 
 #[derive(Diagnostic)]
 #[diag(codegen_llvm_autodiff_component_unavailable)]
-pub(crate) struct AutoDiffComponentUnavailable;
+pub(crate) struct AutoDiffComponentUnavailable {
+    pub err: String,
+}
+
+#[derive(Diagnostic)]
+#[diag(codegen_llvm_autodiff_component_missing)]
+#[note]
+pub(crate) struct AutoDiffComponentMissing {
+    pub err: String,
+}
 
 #[derive(Diagnostic)]
 #[diag(codegen_llvm_autodiff_without_lto)]

compiler/rustc_codegen_llvm/src/intrinsic.rs

@@ -560,6 +560,12 @@ impl<'ll, 'tcx> IntrinsicCallBuilderMethods<'tcx> for Builder<'_, 'll, 'tcx> {
                 return Ok(());
             }
 
+            sym::amdgpu_dispatch_ptr => {
+                let val = self.call_intrinsic("llvm.amdgcn.dispatch.ptr", &[], &[]);
+                // Relying on `LLVMBuildPointerCast` to produce an addrspacecast
+                self.pointercast(val, self.type_ptr())
+            }
+
             _ if name.as_str().starts_with("simd_") => {
                 // Unpack non-power-of-2 #[repr(packed, simd)] arguments.
                 // This gives them the expected layout of a regular #[repr(simd)] vector.

compiler/rustc_codegen_llvm/src/lib.rs

@@ -249,8 +249,14 @@ impl CodegenBackend for LlvmCodegenBackend {
 
             use crate::back::lto::enable_autodiff_settings;
             if sess.opts.unstable_opts.autodiff.contains(&AutoDiff::Enable) {
-                if let Err(_) = llvm::EnzymeWrapper::get_or_init(&sess.opts.sysroot) {
-                    sess.dcx().emit_fatal(crate::errors::AutoDiffComponentUnavailable);
+                match llvm::EnzymeWrapper::get_or_init(&sess.opts.sysroot) {
+                    Ok(_) => {}
+                    Err(llvm::EnzymeLibraryError::NotFound { err }) => {
+                        sess.dcx().emit_fatal(crate::errors::AutoDiffComponentMissing { err });
+                    }
+                    Err(llvm::EnzymeLibraryError::LoadFailed { err }) => {
+                        sess.dcx().emit_fatal(crate::errors::AutoDiffComponentUnavailable { err });
+                    }
                 }
                 enable_autodiff_settings(&sess.opts.unstable_opts.autodiff);
             }

compiler/rustc_codegen_llvm/src/llvm/enzyme_ffi.rs

@@ -153,7 +153,7 @@ pub(crate) mod Enzyme_AD {
     fn load_ptr_by_symbol_mut_void(
         lib: &libloading::Library,
         bytes: &[u8],
-    ) -> Result<*mut c_void, Box<dyn std::error::Error>> {
+    ) -> Result<*mut c_void, libloading::Error> {
         unsafe {
             let s: libloading::Symbol<'_, *mut c_void> = lib.get(bytes)?;
             // libloading = 0.9.0: try_as_raw_ptr always succeeds and returns Some
@@ -192,15 +192,27 @@ pub(crate) mod Enzyme_AD {
 
     static ENZYME_INSTANCE: OnceLock<Mutex<EnzymeWrapper>> = OnceLock::new();
 
+    #[derive(Debug)]
+    pub(crate) enum EnzymeLibraryError {
+        NotFound { err: String },
+        LoadFailed { err: String },
+    }
+
+    impl From<libloading::Error> for EnzymeLibraryError {
+        fn from(err: libloading::Error) -> Self {
+            Self::LoadFailed { err: format!("{err:?}") }
+        }
+    }
+
     impl EnzymeWrapper {
         /// Initialize EnzymeWrapper with the given sysroot if not already initialized.
         /// Safe to call multiple times - subsequent calls are no-ops due to OnceLock.
         pub(crate) fn get_or_init(
             sysroot: &rustc_session::config::Sysroot,
-        ) -> Result<MutexGuard<'static, Self>, Box<dyn std::error::Error>> {
+        ) -> Result<MutexGuard<'static, Self>, EnzymeLibraryError> {
             let mtx: &'static Mutex<EnzymeWrapper> = ENZYME_INSTANCE.get_or_try_init(|| {
                 let w = Self::call_dynamic(sysroot)?;
-                Ok::<_, Box<dyn std::error::Error>>(Mutex::new(w))
+                Ok::<_, EnzymeLibraryError>(Mutex::new(w))
             })?;
 
             Ok(mtx.lock().unwrap())
@@ -351,7 +363,7 @@ pub(crate) mod Enzyme_AD {
         #[allow(non_snake_case)]
         fn call_dynamic(
             sysroot: &rustc_session::config::Sysroot,
-        ) -> Result<Self, Box<dyn std::error::Error>> {
+        ) -> Result<Self, EnzymeLibraryError> {
             let enzyme_path = Self::get_enzyme_path(sysroot)?;
             let lib = unsafe { libloading::Library::new(enzyme_path)? };
 
@@ -416,7 +428,7 @@ pub(crate) mod Enzyme_AD {
             })
         }
 
-        fn get_enzyme_path(sysroot: &Sysroot) -> Result<String, String> {
+        fn get_enzyme_path(sysroot: &Sysroot) -> Result<String, EnzymeLibraryError> {
             let llvm_version_major = unsafe { LLVMRustVersionMajor() };
 
             let path_buf = sysroot
@@ -434,15 +446,19 @@ pub(crate) mod Enzyme_AD {
                         .map(|p| p.join("lib").display().to_string())
                         .collect::<Vec<String>>()
                         .join("\n* ");
-                    format!(
-                        "failed to find a `libEnzyme-{llvm_version_major}` folder \
+                    EnzymeLibraryError::NotFound {
+                        err: format!(
+                            "failed to find a `libEnzyme-{llvm_version_major}` folder \
                     in the sysroot candidates:\n* {candidates}"
-                    )
+                        ),
+                    }
                 })?;
 
             Ok(path_buf
                 .to_str()
-                .ok_or_else(|| format!("invalid UTF-8 in path: {}", path_buf.display()))?
+                .ok_or_else(|| EnzymeLibraryError::LoadFailed {
+                    err: format!("invalid UTF-8 in path: {}", path_buf.display()),
+                })?
                 .to_string())
         }
     }

compiler/rustc_codegen_ssa/src/mir/intrinsic.rs

@@ -112,6 +112,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                 | sym::unreachable
                 | sym::cold_path
                 | sym::breakpoint
+                | sym::amdgpu_dispatch_ptr
                 | sym::assert_zero_valid
                 | sym::assert_mem_uninitialized_valid
                 | sym::assert_inhabited

compiler/rustc_hir/src/hir.rs

@@ -1409,6 +1409,14 @@ impl AttributeExt for Attribute {
         }
     }
 
+    #[inline]
+    fn deprecation_note(&self) -> Option<Symbol> {
+        match &self {
+            Attribute::Parsed(AttributeKind::Deprecation { deprecation, .. }) => deprecation.note,
+            _ => None,
+        }
+    }
+
     fn is_automatically_derived_attr(&self) -> bool {
         matches!(self, Attribute::Parsed(AttributeKind::AutomaticallyDerived(..)))
     }

compiler/rustc_hir_analysis/src/check/intrinsic.rs

@@ -70,6 +70,7 @@ fn intrinsic_operation_unsafety(tcx: TyCtxt<'_>, intrinsic_id: LocalDefId) -> hi
         | sym::add_with_overflow
         | sym::aggregate_raw_ptr
         | sym::align_of
+        | sym::amdgpu_dispatch_ptr
         | sym::assert_inhabited
         | sym::assert_mem_uninitialized_valid
         | sym::assert_zero_valid
@@ -285,6 +286,7 @@ pub(crate) fn check_intrinsic_type(
     let (n_tps, n_cts, inputs, output) = match intrinsic_name {
         sym::autodiff => (4, 0, vec![param(0), param(1), param(2)], param(3)),
         sym::abort => (0, 0, vec![], tcx.types.never),
+        sym::amdgpu_dispatch_ptr => (0, 0, vec![], Ty::new_imm_ptr(tcx, tcx.types.unit)),
         sym::unreachable => (0, 0, vec![], tcx.types.never),
         sym::breakpoint => (0, 0, vec![], tcx.types.unit),
         sym::size_of | sym::align_of | sym::variant_count => (1, 0, vec![], tcx.types.usize),

compiler/rustc_resolve/src/rustdoc.rs

@@ -410,8 +410,17 @@ pub fn may_be_doc_link(link_type: LinkType) -> bool {
 /// Simplified version of `preprocessed_markdown_links` from rustdoc.
 /// Must return at least the same links as it, but may add some more links on top of that.
 pub(crate) fn attrs_to_preprocessed_links<A: AttributeExt + Clone>(attrs: &[A]) -> Vec<Box<str>> {
-    let (doc_fragments, _) = attrs_to_doc_fragments(attrs.iter().map(|attr| (attr, None)), true);
-    let doc = prepare_to_doc_link_resolution(&doc_fragments).into_values().next().unwrap();
+    let (doc_fragments, other_attrs) =
+        attrs_to_doc_fragments(attrs.iter().map(|attr| (attr, None)), false);
+    let mut doc =
+        prepare_to_doc_link_resolution(&doc_fragments).into_values().next().unwrap_or_default();
+
+    for attr in other_attrs {
+        if let Some(note) = attr.deprecation_note() {
+            doc += note.as_str();
+            doc += "\n";
+        }
+    }
 
     parse_links(&doc)
 }

compiler/rustc_span/src/symbol.rs

@@ -454,6 +454,7 @@ symbols! {
         alu32,
         always,
         amdgpu,
+        amdgpu_dispatch_ptr,
         analysis,
         and,
         and_then,

library/core/src/intrinsics/gpu.rs

@@ -0,0 +1,23 @@
+//! Intrinsics for GPU targets.
+//!
+//! Intrinsics in this module are intended for use on GPU targets.
+//! They can be target specific but in general GPU targets are similar.
+
+#![unstable(feature = "gpu_intrinsics", issue = "none")]
+
+/// Returns a pointer to the HSA kernel dispatch packet.
+///
+/// A `gpu-kernel` on amdgpu is always launched through a kernel dispatch packet.
+/// The dispatch packet contains the workgroup size, launch size and other data.
+/// The content is defined by the [HSA Platform System Architecture Specification],
+/// which is implemented e.g. in AMD's [hsa.h].
+/// The intrinsic returns a unit pointer so that rustc does not need to know the packet struct.
+/// The pointer is valid for the whole lifetime of the program.
+///
+/// [HSA Platform System Architecture Specification]: https://hsafoundation.com/wp-content/uploads/2021/02/HSA-SysArch-1.2.pdf
+/// [hsa.h]: https://github.com/ROCm/rocm-systems/blob/rocm-7.1.0/projects/rocr-runtime/runtime/hsa-runtime/inc/hsa.h#L2959
+#[rustc_nounwind]
+#[rustc_intrinsic]
+#[cfg(target_arch = "amdgpu")]
+#[must_use = "returns a pointer that does nothing unless used"]
+pub fn amdgpu_dispatch_ptr() -> *const ();

library/core/src/intrinsics/mod.rs

@@ -60,6 +60,7 @@ use crate::{mem, ptr};
 
 mod bounds;
 pub mod fallback;
+pub mod gpu;
 pub mod mir;
 pub mod simd;
 

library/core/src/sync/atomic.rs

@@ -1550,6 +1550,24 @@ impl<T> AtomicPtr<T> {
         unsafe { &*ptr.cast() }
     }
 
+    /// Creates a new `AtomicPtr` initialized with a null pointer.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// #![feature(atomic_ptr_null)]
+    /// use std::sync::atomic::{AtomicPtr, Ordering};
+    ///
+    /// let atomic_ptr = AtomicPtr::<()>::null();
+    /// assert!(atomic_ptr.load(Ordering::Relaxed).is_null());
+    /// ```
+    #[inline]
+    #[must_use]
+    #[unstable(feature = "atomic_ptr_null", issue = "150733")]
+    pub const fn null() -> AtomicPtr<T> {
+        AtomicPtr::new(crate::ptr::null_mut())
+    }
+
     /// Returns a mutable reference to the underlying pointer.
     ///
     /// This is safe because the mutable reference guarantees that no other threads are

src/librustdoc/clean/types.rs

@@ -7,6 +7,7 @@ use std::{fmt, iter};
 use arrayvec::ArrayVec;
 use itertools::Either;
 use rustc_abi::{ExternAbi, VariantIdx};
+use rustc_ast::attr::AttributeExt;
 use rustc_data_structures::fx::{FxHashSet, FxIndexMap, FxIndexSet};
 use rustc_data_structures::thin_vec::ThinVec;
 use rustc_hir::attrs::{AttributeKind, DeprecatedSince, Deprecation, DocAttribute};
@@ -450,7 +451,16 @@ impl Item {
     }
 
     pub(crate) fn attr_span(&self, tcx: TyCtxt<'_>) -> rustc_span::Span {
+        let deprecation_notes = self
+            .attrs
+            .other_attrs
+            .iter()
+            .filter_map(|attr| attr.deprecation_note().map(|_| attr.span()));
+
         span_of_fragments(&self.attrs.doc_strings)
+            .into_iter()
+            .chain(deprecation_notes)
+            .reduce(|a, b| a.to(b))
             .unwrap_or_else(|| self.span(tcx).map_or(DUMMY_SP, |span| span.inner()))
     }
 

src/librustdoc/html/markdown.rs

@@ -111,7 +111,11 @@ pub(crate) struct MarkdownWithToc<'a> {
 }
 /// A tuple struct like `Markdown` that renders the markdown escaping HTML tags
 /// and includes no paragraph tags.
-pub(crate) struct MarkdownItemInfo<'a>(pub(crate) &'a str, pub(crate) &'a mut IdMap);
+pub(crate) struct MarkdownItemInfo<'a> {
+    pub(crate) content: &'a str,
+    pub(crate) links: &'a [RenderedLink],
+    pub(crate) ids: &'a mut IdMap,
+}
 /// A tuple struct like `Markdown` that renders only the first paragraph.
 pub(crate) struct MarkdownSummaryLine<'a>(pub &'a str, pub &'a [RenderedLink]);
 
@@ -1459,15 +1463,28 @@ impl MarkdownWithToc<'_> {
     }
 }
 
-impl MarkdownItemInfo<'_> {
+impl<'a> MarkdownItemInfo<'a> {
+    pub(crate) fn new(content: &'a str, links: &'a [RenderedLink], ids: &'a mut IdMap) -> Self {
+        Self { content, links, ids }
+    }
+
     pub(crate) fn write_into(self, mut f: impl fmt::Write) -> fmt::Result {
-        let MarkdownItemInfo(md, ids) = self;
+        let MarkdownItemInfo { content: md, links, ids } = self;
 
         // This is actually common enough to special-case
         if md.is_empty() {
             return Ok(());
         }
-        let p = Parser::new_ext(md, main_body_opts()).into_offset_iter();
+
+        let replacer = move |broken_link: BrokenLink<'_>| {
+            links
+                .iter()
+                .find(|link| *link.original_text == *broken_link.reference)
+                .map(|link| (link.href.as_str().into(), link.tooltip.as_str().into()))
+        };
+
+        let p = Parser::new_with_broken_link_callback(md, main_body_opts(), Some(replacer));
+        let p = p.into_offset_iter();
 
         // Treat inline HTML as plain text.
         let p = p.map(|event| match event.0 {
@@ -1477,6 +1494,7 @@ impl MarkdownItemInfo<'_> {
 
         ids.handle_footnotes(|ids, existing_footnotes| {
             let p = HeadingLinks::new(p, None, ids, HeadingOffset::H1);
+            let p = SpannedLinkReplacer::new(p, links);
             let p = footnotes::Footnotes::new(p, existing_footnotes);
             let p = TableWrapper::new(p.map(|(ev, _)| ev));
             let p = p.filter(|event| {