Auto merge of #80114 - GuillaumeGomez:rollup-gszr5kn, r=GuillaumeGomez

Rollup of 5 pull requests

Successful merges:

 - #80006 (BTreeMap: more expressive local variables in merge)
 - #80022 (BTreeSet: simplify implementation of pop_first/pop_last)
 - #80035 (Optimization for bool's PartialOrd impl)
 - #80040 (Always run intrinsics lowering pass)
 - #80047 (Use more symbols in rustdoc)

Failed merges:

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

compiler/rustc_codegen_ssa/src/mir/intrinsic.rs

@@ -83,9 +83,6 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                 return;
             }
 
-            sym::unreachable => {
-                return;
-            }
             sym::va_start => bx.va_start(args[0].immediate()),
             sym::va_end => bx.va_end(args[0].immediate()),
             sym::size_of_val => {
@@ -106,8 +103,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                     bx.const_usize(bx.layout_of(tp_ty).align.abi.bytes())
                 }
             }
-            sym::size_of
-            | sym::pref_align_of
+            sym::pref_align_of
             | sym::min_align_of
             | sym::needs_drop
             | sym::type_id
@@ -119,10 +115,6 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                     .unwrap();
                 OperandRef::from_const(bx, value, ret_ty).immediate_or_packed_pair(bx)
             }
-            // Effectively no-op
-            sym::forget => {
-                return;
-            }
             sym::offset => {
                 let ptr = args[0].immediate();
                 let offset = args[1].immediate();
@@ -218,9 +210,6 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
             sym::add_with_overflow
             | sym::sub_with_overflow
             | sym::mul_with_overflow
-            | sym::wrapping_add
-            | sym::wrapping_sub
-            | sym::wrapping_mul
             | sym::unchecked_div
             | sym::unchecked_rem
             | sym::unchecked_shl
@@ -254,9 +243,6 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
 
                             return;
                         }
-                        sym::wrapping_add => bx.add(args[0].immediate(), args[1].immediate()),
-                        sym::wrapping_sub => bx.sub(args[0].immediate(), args[1].immediate()),
-                        sym::wrapping_mul => bx.mul(args[0].immediate(), args[1].immediate()),
                         sym::exact_div => {
                             if signed {
                                 bx.exactsdiv(args[0].immediate(), args[1].immediate())

compiler/rustc_mir/src/interpret/intrinsics.rs

@@ -61,12 +61,11 @@ crate fn eval_nullary_intrinsic<'tcx>(
             ConstValue::Slice { data: alloc, start: 0, end: alloc.len() }
         }
         sym::needs_drop => ConstValue::from_bool(tp_ty.needs_drop(tcx, param_env)),
-        sym::size_of | sym::min_align_of | sym::pref_align_of => {
+        sym::min_align_of | sym::pref_align_of => {
             let layout = tcx.layout_of(param_env.and(tp_ty)).map_err(|e| err_inval!(Layout(e)))?;
             let n = match name {
                 sym::pref_align_of => layout.align.pref.bytes(),
                 sym::min_align_of => layout.align.abi.bytes(),
-                sym::size_of => layout.size.bytes(),
                 _ => bug!(),
             };
             ConstValue::from_machine_usize(n, &tcx)
@@ -125,7 +124,6 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
         let (dest, ret) = match ret {
             None => match intrinsic_name {
                 sym::transmute => throw_ub_format!("transmuting to uninhabited type"),
-                sym::unreachable => throw_ub!(Unreachable),
                 sym::abort => M::abort(self, "the program aborted execution".to_owned())?,
                 // Unsupported diverging intrinsic.
                 _ => return Ok(false),
@@ -160,13 +158,12 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
             sym::min_align_of
             | sym::pref_align_of
             | sym::needs_drop
-            | sym::size_of
             | sym::type_id
             | sym::type_name
             | sym::variant_count => {
                 let gid = GlobalId { instance, promoted: None };
                 let ty = match intrinsic_name {
-                    sym::min_align_of | sym::pref_align_of | sym::size_of | sym::variant_count => {
+                    sym::min_align_of | sym::pref_align_of | sym::variant_count => {
                         self.tcx.types.usize
                     }
                     sym::needs_drop => self.tcx.types.bool,
@@ -212,28 +209,16 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
                 let out_val = numeric_intrinsic(intrinsic_name, bits, kind)?;
                 self.write_scalar(out_val, dest)?;
             }
-            sym::wrapping_add
-            | sym::wrapping_sub
-            | sym::wrapping_mul
-            | sym::add_with_overflow
-            | sym::sub_with_overflow
-            | sym::mul_with_overflow => {
+            sym::add_with_overflow | sym::sub_with_overflow | sym::mul_with_overflow => {
                 let lhs = self.read_immediate(args[0])?;
                 let rhs = self.read_immediate(args[1])?;
-                let (bin_op, ignore_overflow) = match intrinsic_name {
-                    sym::wrapping_add => (BinOp::Add, true),
-                    sym::wrapping_sub => (BinOp::Sub, true),
-                    sym::wrapping_mul => (BinOp::Mul, true),
-                    sym::add_with_overflow => (BinOp::Add, false),
-                    sym::sub_with_overflow => (BinOp::Sub, false),
-                    sym::mul_with_overflow => (BinOp::Mul, false),
+                let bin_op = match intrinsic_name {
+                    sym::add_with_overflow => BinOp::Add,
+                    sym::sub_with_overflow => BinOp::Sub,
+                    sym::mul_with_overflow => BinOp::Mul,
                     _ => bug!("Already checked for int ops"),
                 };
-                if ignore_overflow {
-                    self.binop_ignore_overflow(bin_op, lhs, rhs, dest)?;
-                } else {
-                    self.binop_with_overflow(bin_op, lhs, rhs, dest)?;
-                }
+                self.binop_with_overflow(bin_op, lhs, rhs, dest)?;
             }
             sym::saturating_add | sym::saturating_sub => {
                 let l = self.read_immediate(args[0])?;

compiler/rustc_mir/src/transform/mod.rs

@@ -364,6 +364,7 @@ fn run_post_borrowck_cleanup_passes<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tc
         // `AddRetag` needs to run after `ElaborateDrops`. Otherwise it should run fairly late,
         // but before optimizations begin.
         &add_retag::AddRetag,
+        &lower_intrinsics::LowerIntrinsics,
         &simplify::SimplifyCfg::new("elaborate-drops"),
         // `Deaggregator` is conceptually part of MIR building, some backends rely on it happening
         // and it can help optimizations.
@@ -392,7 +393,6 @@ fn run_optimization_passes<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
 
     // The main optimizations that we do on MIR.
     let optimizations: &[&dyn MirPass<'tcx>] = &[
-        &lower_intrinsics::LowerIntrinsics,
         &remove_unneeded_drops::RemoveUnneededDrops,
         &match_branches::MatchBranchSimplification,
         // inst combine is after MatchBranchSimplification to clean up Ne(_1, false)

library/alloc/src/collections/btree/node.rs

@@ -1355,66 +1355,65 @@ impl<'a, K: 'a, V: 'a> BalancingContext<'a, K, V> {
     ///
     /// Panics unless we `.can_merge()`.
     pub fn merge(
-        mut self,
+        self,
         track_edge_idx: Option<LeftOrRight<usize>>,
     ) -> Handle<NodeRef<marker::Mut<'a>, K, V, marker::LeafOrInternal>, marker::Edge> {
+        let Handle { node: mut parent_node, idx: parent_idx, _marker } = self.parent;
+        let old_parent_len = parent_node.len();
         let mut left_node = self.left_child;
-        let left_len = left_node.len();
+        let old_left_len = left_node.len();
         let right_node = self.right_child;
         let right_len = right_node.len();
+        let new_left_len = old_left_len + 1 + right_len;
 
-        assert!(left_len + right_len < CAPACITY);
+        assert!(new_left_len <= CAPACITY);
         assert!(match track_edge_idx {
             None => true,
-            Some(LeftOrRight::Left(idx)) => idx <= left_len,
+            Some(LeftOrRight::Left(idx)) => idx <= old_left_len,
             Some(LeftOrRight::Right(idx)) => idx <= right_len,
         });
 
         unsafe {
-            *left_node.reborrow_mut().into_len_mut() += right_len as u16 + 1;
+            *left_node.reborrow_mut().into_len_mut() = new_left_len as u16;
 
-            let parent_key = slice_remove(
-                self.parent.node.reborrow_mut().into_key_area_slice(),
-                self.parent.idx,
-            );
-            left_node.reborrow_mut().into_key_area_mut_at(left_len).write(parent_key);
+            let parent_key =
+                slice_remove(parent_node.reborrow_mut().into_key_area_slice(), parent_idx);
+            left_node.reborrow_mut().into_key_area_mut_at(old_left_len).write(parent_key);
             ptr::copy_nonoverlapping(
                 right_node.reborrow().key_area().as_ptr(),
-                left_node.reborrow_mut().into_key_area_slice().as_mut_ptr().add(left_len + 1),
+                left_node.reborrow_mut().into_key_area_slice().as_mut_ptr().add(old_left_len + 1),
                 right_len,
             );
 
-            let parent_val = slice_remove(
-                self.parent.node.reborrow_mut().into_val_area_slice(),
-                self.parent.idx,
-            );
-            left_node.reborrow_mut().into_val_area_mut_at(left_len).write(parent_val);
+            let parent_val =
+                slice_remove(parent_node.reborrow_mut().into_val_area_slice(), parent_idx);
+            left_node.reborrow_mut().into_val_area_mut_at(old_left_len).write(parent_val);
             ptr::copy_nonoverlapping(
                 right_node.reborrow().val_area().as_ptr(),
-                left_node.reborrow_mut().into_val_area_slice().as_mut_ptr().add(left_len + 1),
+                left_node.reborrow_mut().into_val_area_slice().as_mut_ptr().add(old_left_len + 1),
                 right_len,
             );
 
-            slice_remove(
-                &mut self.parent.node.reborrow_mut().into_edge_area_slice(),
-                self.parent.idx + 1,
-            );
-            let parent_old_len = self.parent.node.len();
-            self.parent.node.correct_childrens_parent_links(self.parent.idx + 1..parent_old_len);
-            *self.parent.node.reborrow_mut().into_len_mut() -= 1;
+            slice_remove(&mut parent_node.reborrow_mut().into_edge_area_slice(), parent_idx + 1);
+            parent_node.correct_childrens_parent_links(parent_idx + 1..old_parent_len);
+            *parent_node.reborrow_mut().into_len_mut() -= 1;
 
-            if self.parent.node.height > 1 {
+            if parent_node.height > 1 {
                 // SAFETY: the height of the nodes being merged is one below the height
                 // of the node of this edge, thus above zero, so they are internal.
                 let mut left_node = left_node.reborrow_mut().cast_to_internal_unchecked();
                 let right_node = right_node.cast_to_internal_unchecked();
                 ptr::copy_nonoverlapping(
                     right_node.reborrow().edge_area().as_ptr(),
-                    left_node.reborrow_mut().into_edge_area_slice().as_mut_ptr().add(left_len + 1),
+                    left_node
+                        .reborrow_mut()
+                        .into_edge_area_slice()
+                        .as_mut_ptr()
+                        .add(old_left_len + 1),
                     right_len + 1,
                 );
 
-                left_node.correct_childrens_parent_links(left_len + 1..=left_len + 1 + right_len);
+                left_node.correct_childrens_parent_links(old_left_len + 1..new_left_len + 1);
 
                 Global.deallocate(right_node.node.cast(), Layout::new::<InternalNode<K, V>>());
             } else {
@@ -1424,7 +1423,7 @@ impl<'a, K: 'a, V: 'a> BalancingContext<'a, K, V> {
             let new_idx = match track_edge_idx {
                 None => 0,
                 Some(LeftOrRight::Left(idx)) => idx,
-                Some(LeftOrRight::Right(idx)) => left_len + 1 + idx,
+                Some(LeftOrRight::Right(idx)) => old_left_len + 1 + idx,
             };
             Handle::new_edge(left_node, new_idx)
         }

library/alloc/src/collections/btree/set.rs

@@ -679,7 +679,7 @@ impl<T: Ord> BTreeSet<T> {
     /// ```
     #[unstable(feature = "map_first_last", issue = "62924")]
     pub fn pop_first(&mut self) -> Option<T> {
-        self.map.first_entry().map(|entry| entry.remove_entry().0)
+        self.map.pop_first().map(|kv| kv.0)
     }
 
     /// Removes the last value from the set and returns it, if any.
@@ -701,7 +701,7 @@ impl<T: Ord> BTreeSet<T> {
     /// ```
     #[unstable(feature = "map_first_last", issue = "62924")]
     pub fn pop_last(&mut self) -> Option<T> {
-        self.map.last_entry().map(|entry| entry.remove_entry().0)
+        self.map.pop_last().map(|kv| kv.0)
     }
 
     /// Adds a value to the set.

library/core/src/cmp.rs

@@ -1236,7 +1236,7 @@ mod impls {
     impl PartialOrd for bool {
         #[inline]
         fn partial_cmp(&self, other: &bool) -> Option<Ordering> {
-            (*self as u8).partial_cmp(&(*other as u8))
+            Some(self.cmp(other))
         }
     }
 

src/librustdoc/clean/mod.rs

@@ -207,7 +207,7 @@ impl Clean<ExternalCrate> for CrateNum {
         };
 
         ExternalCrate {
-            name: cx.tcx.crate_name(*self).to_string(),
+            name: cx.tcx.crate_name(*self),
             src: krate_src,
             attrs: cx.tcx.get_attrs(root).clean(cx),
             primitives,

src/librustdoc/clean/types.rs

@@ -51,7 +51,7 @@ thread_local!(crate static MAX_DEF_ID: RefCell<FxHashMap<CrateNum, DefId>> = Def
 
 #[derive(Clone, Debug)]
 crate struct Crate {
-    crate name: String,
+    crate name: Symbol,
     crate version: Option<String>,
     crate src: FileName,
     crate module: Option<Item>,
@@ -66,7 +66,7 @@ crate struct Crate {
 
 #[derive(Clone, Debug)]
 crate struct ExternalCrate {
-    crate name: String,
+    crate name: Symbol,
     crate src: FileName,
     crate attrs: Attributes,
     crate primitives: Vec<(DefId, PrimitiveType)>,

src/librustdoc/formats/cache.rs

@@ -8,6 +8,7 @@ use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_hir::def_id::{CrateNum, DefId, CRATE_DEF_INDEX};
 use rustc_middle::middle::privacy::AccessLevels;
 use rustc_span::source_map::FileName;
+use rustc_span::Symbol;
 
 use crate::clean::{self, GetDefId};
 use crate::config::RenderInfo;
@@ -74,7 +75,7 @@ crate struct Cache {
     crate implementors: FxHashMap<DefId, Vec<Impl>>,
 
     /// Cache of where external crate documentation can be found.
-    crate extern_locations: FxHashMap<CrateNum, (String, PathBuf, ExternalLocation)>,
+    crate extern_locations: FxHashMap<CrateNum, (Symbol, PathBuf, ExternalLocation)>,
 
     /// Cache of where documentation for primitives can be found.
     crate primitive_locations: FxHashMap<clean::PrimitiveType, DefId>,
@@ -173,10 +174,10 @@ impl Cache {
                 },
                 _ => PathBuf::new(),
             };
-            let extern_url = extern_html_root_urls.get(&e.name).map(|u| &**u);
+            let extern_url = extern_html_root_urls.get(&*e.name.as_str()).map(|u| &**u);
             cache
                 .extern_locations
-                .insert(n, (e.name.clone(), src_root, extern_location(e, extern_url, &dst)));
+                .insert(n, (e.name, src_root, extern_location(e, extern_url, &dst)));
 
             let did = DefId { krate: n, index: CRATE_DEF_INDEX };
             cache.external_paths.insert(did, (vec![e.name.to_string()], ItemType::Module));
@@ -195,7 +196,7 @@ impl Cache {
             cache.primitive_locations.insert(prim, def_id);
         }
 
-        cache.stack.push(krate.name.clone());
+        cache.stack.push(krate.name.to_string());
         krate = cache.fold_crate(krate);
 
         for (trait_did, dids, impl_) in cache.orphan_trait_impls.drain(..) {
@@ -340,7 +341,7 @@ impl DocFolder for Cache {
 
         // Keep track of the fully qualified path for this item.
         let pushed = match item.name {
-            Some(ref n) if !n.is_empty() => {
+            Some(n) if !n.is_empty() => {
                 self.stack.push(n.to_string());
                 true
             }

src/librustdoc/formats/renderer.rs

@@ -3,7 +3,6 @@ use std::sync::Arc;
 use rustc_data_structures::sync::Lrc;
 use rustc_session::Session;
 use rustc_span::edition::Edition;
-use rustc_span::Symbol;
 
 use crate::clean;
 use crate::config::{RenderInfo, RenderOptions};
@@ -76,7 +75,7 @@ crate fn run_format<T: FormatRenderer>(
         None => return Ok(()),
     };
 
-    item.name = Some(Symbol::intern(&krate.name));
+    item.name = Some(krate.name);
 
     // Render the crate documentation
     let mut work = vec![(format_renderer.clone(), item)];

src/librustdoc/html/render/cache.rs

@@ -31,7 +31,7 @@ crate fn extern_location(
 ) -> ExternalLocation {
     use ExternalLocation::*;
     // See if there's documentation generated into the local directory
-    let local_location = dst.join(&e.name);
+    let local_location = dst.join(&*e.name.as_str());
     if local_location.is_dir() {
         return Local;
     }