Auto merge of rust-lang#2988 - rust-lang:rustup-2023-07-22, r=oli-obk

Automatic sync from rustc

Author: bors

Cargo.lock

@@ -3367,7 +3367,6 @@ dependencies = [
  "rustc_type_ir",
  "serde_json",
  "smallvec",
- "snap",
  "tempfile",
  "thorin-dwp",
  "tracing",

compiler/rustc_abi/src/lib.rs

@@ -49,6 +49,14 @@ bitflags! {
     }
 }
 
+/// Which niches (beyond the `null` niche) are available on references.
+#[derive(Default, Copy, Clone, Hash, Debug, Eq, PartialEq)]
+#[cfg_attr(feature = "nightly", derive(Encodable, Decodable, HashStable_Generic))]
+pub struct ReferenceNichePolicy {
+    pub size: bool,
+    pub align: bool,
+}
+
 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
 #[cfg_attr(feature = "nightly", derive(Encodable, Decodable, HashStable_Generic))]
 pub enum IntegerType {
@@ -346,6 +354,33 @@ impl TargetDataLayout {
         }
     }
 
+    #[inline]
+    pub fn target_usize_max(&self) -> u64 {
+        self.pointer_size.unsigned_int_max().try_into().unwrap()
+    }
+
+    #[inline]
+    pub fn target_isize_min(&self) -> i64 {
+        self.pointer_size.signed_int_min().try_into().unwrap()
+    }
+
+    #[inline]
+    pub fn target_isize_max(&self) -> i64 {
+        self.pointer_size.signed_int_max().try_into().unwrap()
+    }
+
+    /// Returns the (inclusive) range of possible addresses for an allocation with
+    /// the given size and alignment.
+    ///
+    /// Note that this doesn't take into account target-specific limitations.
+    #[inline]
+    pub fn address_range_for(&self, size: Size, align: Align) -> (u64, u64) {
+        let end = Size::from_bytes(self.target_usize_max());
+        let min = align.bytes();
+        let max = (end - size).align_down_to(align).bytes();
+        (min, max)
+    }
+
     #[inline]
     pub fn vector_align(&self, vec_size: Size) -> AbiAndPrefAlign {
         for &(size, align) in &self.vector_align {
@@ -473,6 +508,12 @@ impl Size {
         Size::from_bytes((self.bytes() + mask) & !mask)
     }
 
+    #[inline]
+    pub fn align_down_to(self, align: Align) -> Size {
+        let mask = align.bytes() - 1;
+        Size::from_bytes(self.bytes() & !mask)
+    }
+
     #[inline]
     pub fn is_aligned(self, align: Align) -> bool {
         let mask = align.bytes() - 1;
@@ -967,6 +1008,43 @@ impl WrappingRange {
         }
     }
 
+    /// Returns `true` if `range` is contained in `self`.
+    #[inline(always)]
+    pub fn contains_range<I: Into<u128> + Ord>(&self, range: RangeInclusive<I>) -> bool {
+        if range.is_empty() {
+            return true;
+        }
+
+        let (vmin, vmax) = range.into_inner();
+        let (vmin, vmax) = (vmin.into(), vmax.into());
+
+        if self.start <= self.end {
+            self.start <= vmin && vmax <= self.end
+        } else {
+            // The last check is needed to cover the following case:
+            // `vmin ... start, end ... vmax`. In this special case there is no gap
+            // between `start` and `end` so we must return true.
+            self.start <= vmin || vmax <= self.end || self.start == self.end + 1
+        }
+    }
+
+    /// Returns `true` if `range` has an overlap with `self`.
+    #[inline(always)]
+    pub fn overlaps_range<I: Into<u128> + Ord>(&self, range: RangeInclusive<I>) -> bool {
+        if range.is_empty() {
+            return false;
+        }
+
+        let (vmin, vmax) = range.into_inner();
+        let (vmin, vmax) = (vmin.into(), vmax.into());
+
+        if self.start <= self.end {
+            self.start <= vmax && vmin <= self.end
+        } else {
+            self.start <= vmax || vmin <= self.end
+        }
+    }
+
     /// Returns `self` with replaced `start`
     #[inline(always)]
     pub fn with_start(mut self, start: u128) -> Self {
@@ -984,9 +1062,15 @@ impl WrappingRange {
     /// Returns `true` if `size` completely fills the range.
     #[inline]
     pub fn is_full_for(&self, size: Size) -> bool {
+        debug_assert!(self.is_in_range_for(size));
+        self.start == (self.end.wrapping_add(1) & size.unsigned_int_max())
+    }
+
+    /// Returns `true` if the range is valid for `size`.
+    #[inline(always)]
+    pub fn is_in_range_for(&self, size: Size) -> bool {
         let max_value = size.unsigned_int_max();
-        debug_assert!(self.start <= max_value && self.end <= max_value);
-        self.start == (self.end.wrapping_add(1) & max_value)
+        self.start <= max_value && self.end <= max_value
     }
 }
 
@@ -1427,16 +1511,21 @@ impl Niche {
 
     pub fn reserve<C: HasDataLayout>(&self, cx: &C, count: u128) -> Option<(u128, Scalar)> {
         assert!(count > 0);
+        if count > self.available(cx) {
+            return None;
+        }
 
         let Self { value, valid_range: v, .. } = *self;
-        let size = value.size(cx);
-        assert!(size.bits() <= 128);
-        let max_value = size.unsigned_int_max();
+        let max_value = value.size(cx).unsigned_int_max();
+        let distance_end_zero = max_value - v.end;
 
-        let niche = v.end.wrapping_add(1)..v.start;
-        let available = niche.end.wrapping_sub(niche.start) & max_value;
-        if count > available {
-            return None;
+        // Null-pointer optimization. This is guaranteed by Rust (at least for `Option<_>`),
+        // and offers better codegen opportunities.
+        if count == 1 && matches!(value, Pointer(_)) && !v.contains(0) {
+            // Select which bound to move to minimize the number of lost niches.
+            let valid_range =
+                if v.start - 1 > distance_end_zero { v.with_end(0) } else { v.with_start(0) };
+            return Some((0, Scalar::Initialized { value, valid_range }));
         }
 
         // Extend the range of valid values being reserved by moving either `v.start` or `v.end` bound.
@@ -1459,7 +1548,6 @@ impl Niche {
             let end = v.end.wrapping_add(count) & max_value;
             Some((start, Scalar::Initialized { value, valid_range: v.with_end(end) }))
         };
-        let distance_end_zero = max_value - v.end;
         if v.start > v.end {
             // zero is unavailable because wrapping occurs
             move_end(v)

compiler/rustc_ast_lowering/src/item.rs

@@ -551,17 +551,6 @@ impl<'hir> LoweringContext<'_, 'hir> {
                 for &(ref use_tree, id) in trees {
                     let new_hir_id = self.local_def_id(id);
 
-                    let mut prefix = prefix.clone();
-
-                    // Give the segments new node-ids since they are being cloned.
-                    for seg in &mut prefix.segments {
-                        // Give the cloned segment the same resolution information
-                        // as the old one (this is needed for stability checking).
-                        let new_id = self.next_node_id();
-                        self.resolver.clone_res(seg.id, new_id);
-                        seg.id = new_id;
-                    }
-
                     // Each `use` import is an item and thus are owners of the
                     // names in the path. Up to this point the nested import is
                     // the current owner, since we want each desugared import to
@@ -570,6 +559,9 @@ impl<'hir> LoweringContext<'_, 'hir> {
                     self.with_hir_id_owner(id, |this| {
                         let mut ident = *ident;
 
+                        // `prefix` is lowered multiple times, but in different HIR owners.
+                        // So each segment gets renewed `HirId` with the same
+                        // `ItemLocalId` and the new owner. (See `lower_node_id`)
                         let kind =
                             this.lower_use_tree(use_tree, &prefix, id, vis_span, &mut ident, attrs);
                         if let Some(attrs) = attrs {

compiler/rustc_ast_lowering/src/lib.rs

@@ -148,10 +148,6 @@ trait ResolverAstLoweringExt {
     fn legacy_const_generic_args(&self, expr: &Expr) -> Option<Vec<usize>>;
     fn get_partial_res(&self, id: NodeId) -> Option<PartialRes>;
     fn get_import_res(&self, id: NodeId) -> PerNS<Option<Res<NodeId>>>;
-    // Clones the resolution (if any) on 'source' and applies it
-    // to 'target'. Used when desugaring a `UseTreeKind::Nested` to
-    // multiple `UseTreeKind::Simple`s
-    fn clone_res(&mut self, source: NodeId, target: NodeId);
     fn get_label_res(&self, id: NodeId) -> Option<NodeId>;
     fn get_lifetime_res(&self, id: NodeId) -> Option<LifetimeRes>;
     fn take_extra_lifetime_params(&mut self, id: NodeId) -> Vec<(Ident, NodeId, LifetimeRes)>;
@@ -184,12 +180,6 @@ impl ResolverAstLoweringExt for ResolverAstLowering {
         None
     }
 
-    fn clone_res(&mut self, source: NodeId, target: NodeId) {
-        if let Some(res) = self.partial_res_map.get(&source) {
-            self.partial_res_map.insert(target, *res);
-        }
-    }
-
     /// Obtains resolution for a `NodeId` with a single resolution.
     fn get_partial_res(&self, id: NodeId) -> Option<PartialRes> {
         self.partial_res_map.get(&id).copied()

compiler/rustc_codegen_gcc/src/lib.rs

@@ -239,6 +239,10 @@ impl WriteBackendMethods for GccCodegenBackend {
         unimplemented!();
     }
 
+    fn print_statistics(&self) {
+        unimplemented!()
+    }
+
     unsafe fn optimize(_cgcx: &CodegenContext<Self>, _diag_handler: &Handler, module: &ModuleCodegen<Self::Module>, config: &ModuleConfig) -> Result<(), FatalError> {
         module.module_llvm.context.set_optimization_level(to_gcc_opt_level(config.opt_level));
         Ok(())

compiler/rustc_codegen_gcc/src/type_of.rs

@@ -339,7 +339,8 @@ impl<'tcx> LayoutGccExt<'tcx> for TyAndLayout<'tcx> {
             return pointee;
         }
 
-        let result = Ty::ty_and_layout_pointee_info_at(*self, cx, offset);
+        let assume_valid_ptr = true;
+        let result = Ty::ty_and_layout_pointee_info_at(*self, cx, offset, assume_valid_ptr);
 
         cx.pointee_infos.borrow_mut().insert((self.ty, offset), result);
         result

compiler/rustc_codegen_llvm/src/context.rs

@@ -33,6 +33,7 @@ use rustc_target::abi::{
 use rustc_target::spec::{HasTargetSpec, RelocModel, Target, TlsModel};
 use smallvec::SmallVec;
 
+use libc::c_uint;
 use std::cell::{Cell, RefCell};
 use std::ffi::CStr;
 use std::str;
@@ -349,6 +350,23 @@ pub unsafe fn create_module<'ll>(
         );
     }
 
+    // Insert `llvm.ident` metadata.
+    //
+    // On the wasm targets it will get hooked up to the "producer" sections
+    // `processed-by` information.
+    let rustc_producer =
+        format!("rustc version {}", option_env!("CFG_VERSION").expect("CFG_VERSION"));
+    let name_metadata = llvm::LLVMMDStringInContext(
+        llcx,
+        rustc_producer.as_ptr().cast(),
+        rustc_producer.as_bytes().len() as c_uint,
+    );
+    llvm::LLVMAddNamedMetadataOperand(
+        llmod,
+        cstr!("llvm.ident").as_ptr(),
+        llvm::LLVMMDNodeInContext(llcx, &name_metadata, 1),
+    );
+
     llmod
 }
 

compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs

@@ -888,21 +888,6 @@ pub fn build_compile_unit_di_node<'ll, 'tcx>(
             llvm::LLVMAddNamedMetadataOperand(debug_context.llmod, llvm_gcov_ident.as_ptr(), val);
         }
 
-        // Insert `llvm.ident` metadata on the wasm targets since that will
-        // get hooked up to the "producer" sections `processed-by` information.
-        if tcx.sess.target.is_like_wasm {
-            let name_metadata = llvm::LLVMMDStringInContext(
-                debug_context.llcontext,
-                rustc_producer.as_ptr().cast(),
-                rustc_producer.as_bytes().len() as c_uint,
-            );
-            llvm::LLVMAddNamedMetadataOperand(
-                debug_context.llmod,
-                cstr!("llvm.ident").as_ptr(),
-                llvm::LLVMMDNodeInContext(debug_context.llcontext, &name_metadata, 1),
-            );
-        }
-
         return unit_metadata;
     };