Auto merge of #96428 - GuillaumeGomez:rollup-4noqr33, r=GuillaumeGomez

Rollup of 8 pull requests

Successful merges:

 - #94022 (Clarify that `Cow::into_owned` returns owned data)
 - #94703 (Fix codegen bug in "ptx-kernel" abi related to arg passing)
 - #95949 (Implement Default for AssertUnwindSafe)
 - #96361 (Switch JS code to ES6)
 - #96372 (Suggest calling method on nested field when struct is missing method)
 - #96386 (simplify `describe_field` func in borrowck's diagnostics part)
 - #96400 (Correct documentation for `Rvalue::ShallowInitBox`)
 - #96415 (Remove references to git.io)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup

compiler/rustc_borrowck/src/diagnostics/mod.rs

@@ -40,6 +40,7 @@ crate use outlives_suggestion::OutlivesSuggestionBuilder;
 crate use region_errors::{ErrorConstraintInfo, RegionErrorKind, RegionErrors};
 crate use region_name::{RegionName, RegionNameSource};
 crate use rustc_const_eval::util::CallKind;
+use rustc_middle::mir::tcx::PlaceTy;
 
 pub(super) struct IncludingDowncast(pub(super) bool);
 
@@ -329,30 +330,20 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
 
     /// End-user visible description of the `field`nth field of `base`
     fn describe_field(&self, place: PlaceRef<'tcx>, field: Field) -> String {
-        // FIXME Place2 Make this work iteratively
-        match place {
-            PlaceRef { local, projection: [] } => {
-                let local = &self.body.local_decls[local];
-                self.describe_field_from_ty(local.ty, field, None)
-            }
+        let place_ty = match place {
+            PlaceRef { local, projection: [] } => PlaceTy::from_ty(self.body.local_decls[local].ty),
             PlaceRef { local, projection: [proj_base @ .., elem] } => match elem {
-                ProjectionElem::Deref => {
-                    self.describe_field(PlaceRef { local, projection: proj_base }, field)
-                }
-                ProjectionElem::Downcast(_, variant_index) => {
-                    let base_ty = place.ty(self.body, self.infcx.tcx).ty;
-                    self.describe_field_from_ty(base_ty, field, Some(*variant_index))
-                }
-                ProjectionElem::Field(_, field_type) => {
-                    self.describe_field_from_ty(*field_type, field, None)
-                }
-                ProjectionElem::Index(..)
+                ProjectionElem::Deref
+                | ProjectionElem::Index(..)
                 | ProjectionElem::ConstantIndex { .. }
                 | ProjectionElem::Subslice { .. } => {
-                    self.describe_field(PlaceRef { local, projection: proj_base }, field)
+                    PlaceRef { local, projection: proj_base }.ty(self.body, self.infcx.tcx)
                 }
+                ProjectionElem::Downcast(..) => place.ty(self.body, self.infcx.tcx),
+                ProjectionElem::Field(_, field_type) => PlaceTy::from_ty(*field_type),
             },
-        }
+        };
+        self.describe_field_from_ty(place_ty.ty, field, place_ty.variant_index)
     }
 
     /// End-user visible description of the `field_index`nth field of `ty`

compiler/rustc_middle/src/mir/mod.rs

@@ -2581,8 +2581,6 @@ pub enum Rvalue<'tcx> {
     /// This is different from a normal transmute because dataflow analysis will treat the box as
     /// initialized but its content as uninitialized. Like other pointer casts, this in general
     /// affects alias analysis.
-    ///
-    /// Disallowed after drop elaboration.
     ShallowInitBox(Operand<'tcx>, Ty<'tcx>),
 }
 

compiler/rustc_middle/src/ty/layout.rs

@@ -2592,6 +2592,22 @@ where
 
         pointee_info
     }
+
+    fn is_adt(this: TyAndLayout<'tcx>) -> bool {
+        matches!(this.ty.kind(), ty::Adt(..))
+    }
+
+    fn is_never(this: TyAndLayout<'tcx>) -> bool {
+        this.ty.kind() == &ty::Never
+    }
+
+    fn is_tuple(this: TyAndLayout<'tcx>) -> bool {
+        matches!(this.ty.kind(), ty::Tuple(..))
+    }
+
+    fn is_unit(this: TyAndLayout<'tcx>) -> bool {
+        matches!(this.ty.kind(), ty::Tuple(list) if list.len() == 0)
+    }
 }
 
 impl<'tcx> ty::Instance<'tcx> {

compiler/rustc_middle/src/ty/list.rs

@@ -61,6 +61,10 @@ impl<T> List<T> {
         static EMPTY_SLICE: InOrder<usize, MaxAlign> = InOrder(0, MaxAlign);
         unsafe { &*(&EMPTY_SLICE as *const _ as *const List<T>) }
     }
+
+    pub fn len(&self) -> usize {
+        self.len
+    }
 }
 
 impl<T: Copy> List<T> {

compiler/rustc_target/src/abi/call/mod.rs

@@ -696,7 +696,13 @@ impl<'a, Ty> FnAbi<'a, Ty> {
             "sparc" => sparc::compute_abi_info(cx, self),
             "sparc64" => sparc64::compute_abi_info(cx, self),
             "nvptx" => nvptx::compute_abi_info(self),
-            "nvptx64" => nvptx64::compute_abi_info(self),
+            "nvptx64" => {
+                if cx.target_spec().adjust_abi(abi) == spec::abi::Abi::PtxKernel {
+                    nvptx64::compute_ptx_kernel_abi_info(cx, self)
+                } else {
+                    nvptx64::compute_abi_info(self)
+                }
+            }
             "hexagon" => hexagon::compute_abi_info(self),
             "riscv32" | "riscv64" => riscv::compute_abi_info(cx, self),
             "wasm32" | "wasm64" => {

compiler/rustc_target/src/abi/call/nvptx64.rs

@@ -1,21 +1,35 @@
-// Reference: PTX Writer's Guide to Interoperability
-// https://docs.nvidia.com/cuda/ptx-writers-guide-to-interoperability
-
-use crate::abi::call::{ArgAbi, FnAbi};
+use crate::abi::call::{ArgAbi, FnAbi, PassMode, Reg, Size, Uniform};
+use crate::abi::{HasDataLayout, TyAbiInterface};
 
 fn classify_ret<Ty>(ret: &mut ArgAbi<'_, Ty>) {
     if ret.layout.is_aggregate() && ret.layout.size.bits() > 64 {
         ret.make_indirect();
-    } else {
-        ret.extend_integer_width_to(64);
     }
 }
 
 fn classify_arg<Ty>(arg: &mut ArgAbi<'_, Ty>) {
     if arg.layout.is_aggregate() && arg.layout.size.bits() > 64 {
         arg.make_indirect();
-    } else {
-        arg.extend_integer_width_to(64);
+    }
+}
+
+fn classify_arg_kernel<'a, Ty, C>(_cx: &C, arg: &mut ArgAbi<'a, Ty>)
+where
+    Ty: TyAbiInterface<'a, C> + Copy,
+    C: HasDataLayout,
+{
+    if matches!(arg.mode, PassMode::Pair(..)) && (arg.layout.is_adt() || arg.layout.is_tuple()) {
+        let align_bytes = arg.layout.align.abi.bytes();
+
+        let unit = match align_bytes {
+            1 => Reg::i8(),
+            2 => Reg::i16(),
+            4 => Reg::i32(),
+            8 => Reg::i64(),
+            16 => Reg::i128(),
+            _ => unreachable!("Align is given as power of 2 no larger than 16 bytes"),
+        };
+        arg.cast_to(Uniform { unit, total: Size::from_bytes(2 * align_bytes) });
     }
 }
 
@@ -31,3 +45,20 @@ pub fn compute_abi_info<Ty>(fn_abi: &mut FnAbi<'_, Ty>) {
         classify_arg(arg);
     }
 }
+
+pub fn compute_ptx_kernel_abi_info<'a, Ty, C>(cx: &C, fn_abi: &mut FnAbi<'a, Ty>)
+where
+    Ty: TyAbiInterface<'a, C> + Copy,
+    C: HasDataLayout,
+{
+    if !fn_abi.ret.layout.is_unit() && !fn_abi.ret.layout.is_never() {
+        panic!("Kernels should not return anything other than () or !");
+    }
+
+    for arg in &mut fn_abi.args {
+        if arg.is_ignore() {
+            continue;
+        }
+        classify_arg_kernel(cx, arg);
+    }
+}

compiler/rustc_target/src/abi/mod.rs

@@ -1355,6 +1355,10 @@ pub trait TyAbiInterface<'a, C>: Sized {
         cx: &C,
         offset: Size,
     ) -> Option<PointeeInfo>;
+    fn is_adt(this: TyAndLayout<'a, Self>) -> bool;
+    fn is_never(this: TyAndLayout<'a, Self>) -> bool;
+    fn is_tuple(this: TyAndLayout<'a, Self>) -> bool;
+    fn is_unit(this: TyAndLayout<'a, Self>) -> bool;
 }
 
 impl<'a, Ty> TyAndLayout<'a, Ty> {
@@ -1396,6 +1400,34 @@ impl<'a, Ty> TyAndLayout<'a, Ty> {
             _ => false,
         }
     }
+
+    pub fn is_adt<C>(self) -> bool
+    where
+        Ty: TyAbiInterface<'a, C>,
+    {
+        Ty::is_adt(self)
+    }
+
+    pub fn is_never<C>(self) -> bool
+    where
+        Ty: TyAbiInterface<'a, C>,
+    {
+        Ty::is_never(self)
+    }
+
+    pub fn is_tuple<C>(self) -> bool
+    where
+        Ty: TyAbiInterface<'a, C>,
+    {
+        Ty::is_tuple(self)
+    }
+
+    pub fn is_unit<C>(self) -> bool
+    where
+        Ty: TyAbiInterface<'a, C>,
+    {
+        Ty::is_unit(self)
+    }
 }
 
 impl<'a, Ty> TyAndLayout<'a, Ty> {

compiler/rustc_target/src/asm/mips.rs

@@ -43,7 +43,8 @@ impl MipsInlineAsmRegClass {
     }
 }
 
-// The reserved registers are somewhat taken from <https://git.io/JUR1k#L150>.
+// The reserved registers are somewhat taken from
+// <https://github.com/llvm/llvm-project/blob/deb8f8bcf31540c657716ea5242183b0792702a1/llvm/lib/Target/Mips/MipsRegisterInfo.cpp#L150>.
 def_regs! {
     Mips MipsInlineAsmReg MipsInlineAsmRegClass {
         r2: reg = ["$2"],

compiler/rustc_typeck/src/check/expr.rs

@@ -2285,14 +2285,17 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         // try to add a suggestion in case the field is a nested field of a field of the Adt
         if let Some((fields, substs)) = self.get_field_candidates(span, expr_t) {
             for candidate_field in fields.iter() {
-                if let Some(field_path) = self.check_for_nested_field(
+                if let Some(mut field_path) = self.check_for_nested_field_satisfying(
                     span,
-                    field,
+                    &|candidate_field, _| candidate_field.ident(self.tcx()) == field,
                     candidate_field,
                     substs,
                     vec![],
                     self.tcx.parent_module(id).to_def_id(),
                 ) {
+                    // field_path includes `field` that we're looking for, so pop it.
+                    field_path.pop();
+
                     let field_path_str = field_path
                         .iter()
                         .map(|id| id.name.to_ident_string())
@@ -2312,7 +2315,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         err
     }
 
-    fn get_field_candidates(
+    crate fn get_field_candidates(
         &self,
         span: Span,
         base_t: Ty<'tcx>,
@@ -2337,49 +2340,42 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 
     /// This method is called after we have encountered a missing field error to recursively
     /// search for the field
-    fn check_for_nested_field(
+    crate fn check_for_nested_field_satisfying(
         &self,
         span: Span,
-        target_field: Ident,
+        matches: &impl Fn(&ty::FieldDef, Ty<'tcx>) -> bool,
         candidate_field: &ty::FieldDef,
         subst: SubstsRef<'tcx>,
         mut field_path: Vec<Ident>,
         id: DefId,
     ) -> Option<Vec<Ident>> {
         debug!(
-            "check_for_nested_field(span: {:?}, candidate_field: {:?}, field_path: {:?}",
+            "check_for_nested_field_satisfying(span: {:?}, candidate_field: {:?}, field_path: {:?}",
             span, candidate_field, field_path
         );
 
-        if candidate_field.ident(self.tcx) == target_field {
-            Some(field_path)
-        } else if field_path.len() > 3 {
+        if field_path.len() > 3 {
             // For compile-time reasons and to avoid infinite recursion we only check for fields
             // up to a depth of three
             None
         } else {
             // recursively search fields of `candidate_field` if it's a ty::Adt
-
             field_path.push(candidate_field.ident(self.tcx).normalize_to_macros_2_0());
             let field_ty = candidate_field.ty(self.tcx, subst);
             if let Some((nested_fields, subst)) = self.get_field_candidates(span, field_ty) {
                 for field in nested_fields.iter() {
-                    let accessible = field.vis.is_accessible_from(id, self.tcx);
-                    if accessible {
-                        let ident = field.ident(self.tcx).normalize_to_macros_2_0();
-                        if ident == target_field {
+                    if field.vis.is_accessible_from(id, self.tcx) {
+                        if matches(candidate_field, field_ty) {
                             return Some(field_path);
-                        }
-                        let field_path = field_path.clone();
-                        if let Some(path) = self.check_for_nested_field(
+                        } else if let Some(field_path) = self.check_for_nested_field_satisfying(
                             span,
-                            target_field,
+                            matches,
                             field,
                             subst,
-                            field_path,
+                            field_path.clone(),
                             id,
                         ) {
-                            return Some(path);
+                            return Some(field_path);
                         }
                     }
                 }

compiler/rustc_typeck/src/check/method/suggest.rs

@@ -28,7 +28,7 @@ use rustc_trait_selection::traits::{
 use std::cmp::Ordering;
 use std::iter;
 
-use super::probe::Mode;
+use super::probe::{Mode, ProbeScope};
 use super::{CandidateSource, MethodError, NoMatchData};
 
 impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
@@ -1129,6 +1129,46 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     label_span_not_found();
                 }
 
+                if let SelfSource::MethodCall(expr) = source
+                    && let Some((fields, substs)) = self.get_field_candidates(span, actual)
+                {
+                    let call_expr =
+                        self.tcx.hir().expect_expr(self.tcx.hir().get_parent_node(expr.hir_id));
+                    for candidate_field in fields.iter() {
+                        if let Some(field_path) = self.check_for_nested_field_satisfying(
+                            span,
+                            &|_, field_ty| {
+                                self.lookup_probe(
+                                    span,
+                                    item_name,
+                                    field_ty,
+                                    call_expr,
+                                    ProbeScope::AllTraits,
+                                )
+                                .is_ok()
+                            },
+                            candidate_field,
+                            substs,
+                            vec![],
+                            self.tcx.parent_module(expr.hir_id).to_def_id(),
+                        ) {
+                            let field_path_str = field_path
+                                .iter()
+                                .map(|id| id.name.to_ident_string())
+                                .collect::<Vec<String>>()
+                                .join(".");
+                            debug!("field_path_str: {:?}", field_path_str);
+
+                            err.span_suggestion_verbose(
+                                item_name.span.shrink_to_lo(),
+                                "one of the expressions' fields has a method of the same name",
+                                format!("{field_path_str}."),
+                                Applicability::MaybeIncorrect,
+                            );
+                        }
+                    }
+                }
+
                 bound_spans.sort();
                 bound_spans.dedup();
                 for (span, msg) in bound_spans.into_iter() {

library/alloc/src/borrow.rs

@@ -292,8 +292,7 @@ impl<B: ?Sized + ToOwned> Cow<'_, B> {
     ///
     /// # Examples
     ///
-    /// Calling `into_owned` on a `Cow::Borrowed` clones the underlying data
-    /// and becomes a `Cow::Owned`:
+    /// Calling `into_owned` on a `Cow::Borrowed` returns a clone of the borrowed data:
     ///
     /// ```
     /// use std::borrow::Cow;
@@ -307,7 +306,8 @@ impl<B: ?Sized + ToOwned> Cow<'_, B> {
     /// );
     /// ```
     ///
-    /// Calling `into_owned` on a `Cow::Owned` is a no-op:
+    /// Calling `into_owned` on a `Cow::Owned` returns the owned data. The data is moved out of the
+    /// `Cow` without being cloned.
     ///
     /// ```
     /// use std::borrow::Cow;