From 4f9fe856a25ab29345b90e7725509e9ee38a37be Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Wed, 17 Apr 2024 14:19:41 +0200 Subject: Adding upstream version 1.69.0+dfsg1. Signed-off-by: Daniel Baumann --- compiler/rustc_abi/src/layout.rs | 146 +++++++++++++++++++-------------------- compiler/rustc_abi/src/lib.rs | 138 +++++++++++++++++++++--------------- 2 files changed, 153 insertions(+), 131 deletions(-) (limited to 'compiler/rustc_abi/src') diff --git a/compiler/rustc_abi/src/layout.rs b/compiler/rustc_abi/src/layout.rs index 9c2cf58ef..54858b520 100644 --- a/compiler/rustc_abi/src/layout.rs +++ b/compiler/rustc_abi/src/layout.rs @@ -1,11 +1,5 @@ use super::*; -use std::{ - borrow::Borrow, - cmp, - fmt::Debug, - iter, - ops::{Bound, Deref}, -}; +use std::{borrow::Borrow, cmp, iter, ops::Bound}; #[cfg(feature = "randomize")] use rand::{seq::SliceRandom, SeedableRng}; @@ -33,7 +27,7 @@ pub trait LayoutCalculator { fn delay_bug(&self, txt: &str); fn current_data_layout(&self) -> Self::TargetDataLayoutRef; - fn scalar_pair(&self, a: Scalar, b: Scalar) -> LayoutS { + fn scalar_pair(&self, a: Scalar, b: Scalar) -> LayoutS { let dl = self.current_data_layout(); let dl = dl.borrow(); let b_align = b.align(dl); @@ -49,7 +43,7 @@ pub trait LayoutCalculator { .max_by_key(|niche| niche.available(dl)); LayoutS { - variants: Variants::Single { index: V::new(0) }, + variants: Variants::Single { index: VariantIdx::new(0) }, fields: FieldsShape::Arbitrary { offsets: vec![Size::ZERO, b_offset], memory_index: vec![0, 1], @@ -61,13 +55,13 @@ pub trait LayoutCalculator { } } - fn univariant<'a, V: Idx, F: Deref> + Debug>( + fn univariant( &self, dl: &TargetDataLayout, - fields: &[F], + fields: &[Layout<'_>], repr: &ReprOptions, kind: StructKind, - ) -> Option> { + ) -> Option { let pack = repr.pack; let mut align = if pack.is_some() { dl.i8_align } else { dl.aggregate_align }; let mut inverse_memory_index: Vec = (0..fields.len() as u32).collect(); @@ -76,17 +70,17 @@ pub trait LayoutCalculator { let end = if let StructKind::MaybeUnsized = kind { fields.len() - 1 } else { fields.len() }; let optimizing = &mut inverse_memory_index[..end]; - let effective_field_align = |f: &F| { + let effective_field_align = |layout: Layout<'_>| { if let Some(pack) = pack { // return the packed alignment in bytes - f.align.abi.min(pack).bytes() + layout.align().abi.min(pack).bytes() } else { // returns log2(effective-align). // This is ok since `pack` applies to all fields equally. // The calculation assumes that size is an integer multiple of align, except for ZSTs. // // group [u8; 4] with align-4 or [u8; 6] with align-2 fields - f.align.abi.bytes().max(f.size.bytes()).trailing_zeros() as u64 + layout.align().abi.bytes().max(layout.size().bytes()).trailing_zeros() as u64 } }; @@ -111,9 +105,9 @@ pub trait LayoutCalculator { // Place ZSTs first to avoid "interesting offsets", // especially with only one or two non-ZST fields. // Then place largest alignments first, largest niches within an alignment group last - let f = &fields[x as usize]; - let niche_size = f.largest_niche.map_or(0, |n| n.available(dl)); - (!f.is_zst(), cmp::Reverse(effective_field_align(f)), niche_size) + let f = fields[x as usize]; + let niche_size = f.largest_niche().map_or(0, |n| n.available(dl)); + (!f.0.is_zst(), cmp::Reverse(effective_field_align(f)), niche_size) }); } @@ -123,8 +117,8 @@ pub trait LayoutCalculator { // And put the largest niche in an alignment group at the end // so it can be used as discriminant in jagged enums optimizing.sort_by_key(|&x| { - let f = &fields[x as usize]; - let niche_size = f.largest_niche.map_or(0, |n| n.available(dl)); + let f = fields[x as usize]; + let niche_size = f.largest_niche().map_or(0, |n| n.available(dl)); (effective_field_align(f), niche_size) }); } @@ -160,15 +154,15 @@ pub trait LayoutCalculator { )); } - if field.is_unsized() { + if field.0.is_unsized() { sized = false; } // Invariant: offset < dl.obj_size_bound() <= 1<<61 let field_align = if let Some(pack) = pack { - field.align.min(AbiAndPrefAlign::new(pack)) + field.align().min(AbiAndPrefAlign::new(pack)) } else { - field.align + field.align() }; offset = offset.align_to(field_align.abi); align = align.max(field_align); @@ -176,7 +170,7 @@ pub trait LayoutCalculator { debug!("univariant offset: {:?} field: {:#?}", offset, field); offsets[i as usize] = offset; - if let Some(mut niche) = field.largest_niche { + if let Some(mut niche) = field.largest_niche() { let available = niche.available(dl); if available > largest_niche_available { largest_niche_available = available; @@ -185,7 +179,7 @@ pub trait LayoutCalculator { } } - offset = offset.checked_add(field.size, dl)?; + offset = offset.checked_add(field.size(), dl)?; } if let Some(repr_align) = repr.align { align = align.max(AbiAndPrefAlign::new(repr_align)); @@ -205,24 +199,26 @@ pub trait LayoutCalculator { // Unpack newtype ABIs and find scalar pairs. if sized && size.bytes() > 0 { // All other fields must be ZSTs. - let mut non_zst_fields = fields.iter().enumerate().filter(|&(_, f)| !f.is_zst()); + let mut non_zst_fields = fields.iter().enumerate().filter(|&(_, f)| !f.0.is_zst()); match (non_zst_fields.next(), non_zst_fields.next(), non_zst_fields.next()) { // We have exactly one non-ZST field. (Some((i, field)), None, None) => { // Field fills the struct and it has a scalar or scalar pair ABI. - if offsets[i].bytes() == 0 && align.abi == field.align.abi && size == field.size + if offsets[i].bytes() == 0 + && align.abi == field.align().abi + && size == field.size() { - match field.abi { + match field.abi() { // For plain scalars, or vectors of them, we can't unpack // newtypes for `#[repr(C)]`, as that affects C ABIs. Abi::Scalar(_) | Abi::Vector { .. } if optimize => { - abi = field.abi; + abi = field.abi(); } // But scalar pairs are Rust-specific and get // treated as aggregates by C ABIs anyway. Abi::ScalarPair(..) => { - abi = field.abi; + abi = field.abi(); } _ => {} } @@ -231,7 +227,7 @@ pub trait LayoutCalculator { // Two non-ZST fields, and they're both scalars. (Some((i, a)), Some((j, b)), None) => { - match (a.abi, b.abi) { + match (a.abi(), b.abi()) { (Abi::Scalar(a), Abi::Scalar(b)) => { // Order by the memory placement, not source order. let ((i, a), (j, b)) = if offsets[i] < offsets[j] { @@ -239,7 +235,7 @@ pub trait LayoutCalculator { } else { ((j, b), (i, a)) }; - let pair = self.scalar_pair::(a, b); + let pair = self.scalar_pair(a, b); let pair_offsets = match pair.fields { FieldsShape::Arbitrary { ref offsets, ref memory_index } => { assert_eq!(memory_index, &[0, 1]); @@ -264,11 +260,11 @@ pub trait LayoutCalculator { _ => {} } } - if fields.iter().any(|f| f.abi.is_uninhabited()) { + if fields.iter().any(|f| f.abi().is_uninhabited()) { abi = Abi::Uninhabited; } Some(LayoutS { - variants: Variants::Single { index: V::new(0) }, + variants: Variants::Single { index: VariantIdx::new(0) }, fields: FieldsShape::Arbitrary { offsets, memory_index }, abi, largest_niche, @@ -277,11 +273,11 @@ pub trait LayoutCalculator { }) } - fn layout_of_never_type(&self) -> LayoutS { + fn layout_of_never_type(&self) -> LayoutS { let dl = self.current_data_layout(); let dl = dl.borrow(); LayoutS { - variants: Variants::Single { index: V::new(0) }, + variants: Variants::Single { index: VariantIdx::new(0) }, fields: FieldsShape::Primitive, abi: Abi::Uninhabited, largest_niche: None, @@ -290,18 +286,18 @@ pub trait LayoutCalculator { } } - fn layout_of_struct_or_enum<'a, V: Idx, F: Deref> + Debug>( + fn layout_of_struct_or_enum( &self, repr: &ReprOptions, - variants: &IndexVec>, + variants: &IndexVec>>, is_enum: bool, is_unsafe_cell: bool, scalar_valid_range: (Bound, Bound), discr_range_of_repr: impl Fn(i128, i128) -> (Integer, bool), - discriminants: impl Iterator, + discriminants: impl Iterator, niche_optimize_enum: bool, always_sized: bool, - ) -> Option> { + ) -> Option { let dl = self.current_data_layout(); let dl = dl.borrow(); @@ -316,9 +312,9 @@ pub trait LayoutCalculator { // but *not* an encoding of the discriminant (e.g., a tag value). // See issue #49298 for more details on the need to leave space // for non-ZST uninhabited data (mostly partial initialization). - let absent = |fields: &[F]| { - let uninhabited = fields.iter().any(|f| f.abi.is_uninhabited()); - let is_zst = fields.iter().all(|f| f.is_zst()); + let absent = |fields: &[Layout<'_>]| { + let uninhabited = fields.iter().any(|f| f.abi().is_uninhabited()); + let is_zst = fields.iter().all(|f| f.0.is_zst()); uninhabited && is_zst }; let (present_first, present_second) = { @@ -335,7 +331,7 @@ pub trait LayoutCalculator { } // If it's a struct, still compute a layout so that we can still compute the // field offsets. - None => V::new(0), + None => VariantIdx::new(0), }; let is_struct = !is_enum || @@ -439,12 +435,12 @@ pub trait LayoutCalculator { // variant layouts, so we can't store them in the // overall LayoutS. Store the overall LayoutS // and the variant LayoutSs here until then. - struct TmpLayout { - layout: LayoutS, - variants: IndexVec>, + struct TmpLayout { + layout: LayoutS, + variants: IndexVec, } - let calculate_niche_filling_layout = || -> Option> { + let calculate_niche_filling_layout = || -> Option { if niche_optimize_enum { return None; } @@ -464,15 +460,16 @@ pub trait LayoutCalculator { Some(st) }) - .collect::>>()?; + .collect::>>()?; let largest_variant_index = variant_layouts .iter_enumerated() .max_by_key(|(_i, layout)| layout.size.bytes()) .map(|(i, _layout)| i)?; - let all_indices = (0..=variants.len() - 1).map(V::new); - let needs_disc = |index: V| index != largest_variant_index && !absent(&variants[index]); + let all_indices = (0..=variants.len() - 1).map(VariantIdx::new); + let needs_disc = + |index: VariantIdx| index != largest_variant_index && !absent(&variants[index]); let niche_variants = all_indices.clone().find(|v| needs_disc(*v)).unwrap().index() ..=all_indices.rev().find(|v| needs_disc(*v)).unwrap().index(); @@ -482,7 +479,7 @@ pub trait LayoutCalculator { let (field_index, niche, (niche_start, niche_scalar)) = variants[largest_variant_index] .iter() .enumerate() - .filter_map(|(j, field)| Some((j, field.largest_niche?))) + .filter_map(|(j, field)| Some((j, field.largest_niche()?))) .max_by_key(|(_, niche)| niche.available(dl)) .and_then(|(j, niche)| Some((j, niche, niche.reserve(dl, count)?)))?; let niche_offset = @@ -514,7 +511,7 @@ pub trait LayoutCalculator { match layout.fields { FieldsShape::Arbitrary { ref mut offsets, .. } => { for (j, offset) in offsets.iter_mut().enumerate() { - if !variants[i][j].is_zst() { + if !variants[i][j].0.is_zst() { *offset += this_offset; } } @@ -572,8 +569,8 @@ pub trait LayoutCalculator { tag: niche_scalar, tag_encoding: TagEncoding::Niche { untagged_variant: largest_variant_index, - niche_variants: (V::new(*niche_variants.start()) - ..=V::new(*niche_variants.end())), + niche_variants: (VariantIdx::new(*niche_variants.start()) + ..=VariantIdx::new(*niche_variants.end())), niche_start, }, tag_field: 0, @@ -598,7 +595,7 @@ pub trait LayoutCalculator { let discr_type = repr.discr_type(); let bits = Integer::from_attr(dl, discr_type).size().bits(); for (i, mut val) in discriminants { - if variants[i].iter().any(|f| f.abi.is_uninhabited()) { + if variants[i].iter().any(|f| f.abi().is_uninhabited()) { continue; } if discr_type.is_signed() { @@ -636,7 +633,7 @@ pub trait LayoutCalculator { if repr.c() { for fields in variants { for field in fields { - prefix_align = prefix_align.max(field.align.abi); + prefix_align = prefix_align.max(field.align().abi); } } } @@ -655,8 +652,8 @@ pub trait LayoutCalculator { // Find the first field we can't move later // to make room for a larger discriminant. for field in st.fields.index_by_increasing_offset().map(|j| &field_layouts[j]) { - if !field.is_zst() || field.align.abi.bytes() != 1 { - start_align = start_align.min(field.align.abi); + if !field.0.is_zst() || field.align().abi.bytes() != 1 { + start_align = start_align.min(field.align().abi); break; } } @@ -664,7 +661,7 @@ pub trait LayoutCalculator { align = align.max(st.align); Some(st) }) - .collect::>>()?; + .collect::>>()?; // Align the maximum variant size to the largest alignment. size = size.align_to(align.abi); @@ -759,7 +756,7 @@ pub trait LayoutCalculator { let FieldsShape::Arbitrary { ref offsets, .. } = layout_variant.fields else { panic!(); }; - let mut fields = iter::zip(field_layouts, offsets).filter(|p| !p.0.is_zst()); + let mut fields = iter::zip(field_layouts, offsets).filter(|p| !p.0.0.is_zst()); let (field, offset) = match (fields.next(), fields.next()) { (None, None) => { common_prim_initialized_in_all_variants = false; @@ -771,7 +768,7 @@ pub trait LayoutCalculator { break; } }; - let prim = match field.abi { + let prim = match field.abi() { Abi::Scalar(scalar) => { common_prim_initialized_in_all_variants &= matches!(scalar, Scalar::Initialized { .. }); @@ -802,7 +799,7 @@ pub trait LayoutCalculator { // Common prim might be uninit. Scalar::Union { value: prim } }; - let pair = self.scalar_pair::(tag, prim_scalar); + let pair = self.scalar_pair(tag, prim_scalar); let pair_offsets = match pair.fields { FieldsShape::Arbitrary { ref offsets, ref memory_index } => { assert_eq!(memory_index, &[0, 1]); @@ -862,9 +859,8 @@ pub trait LayoutCalculator { // pick the layout with the larger niche; otherwise, // pick tagged as it has simpler codegen. use cmp::Ordering::*; - let niche_size = |tmp_l: &TmpLayout| { - tmp_l.layout.largest_niche.map_or(0, |n| n.available(dl)) - }; + let niche_size = + |tmp_l: &TmpLayout| tmp_l.layout.largest_niche.map_or(0, |n| n.available(dl)); match (tl.layout.size.cmp(&nl.layout.size), niche_size(&tl).cmp(&niche_size(&nl))) { (Greater, _) => nl, (Equal, Less) => nl, @@ -884,11 +880,11 @@ pub trait LayoutCalculator { Some(best_layout.layout) } - fn layout_of_union<'a, V: Idx, F: Deref> + Debug>( + fn layout_of_union( &self, repr: &ReprOptions, - variants: &IndexVec>, - ) -> Option> { + variants: &IndexVec>>, + ) -> Option { let dl = self.current_data_layout(); let dl = dl.borrow(); let mut align = if repr.pack.is_some() { dl.i8_align } else { dl.aggregate_align }; @@ -900,15 +896,15 @@ pub trait LayoutCalculator { let optimize = !repr.inhibit_union_abi_opt(); let mut size = Size::ZERO; let mut abi = Abi::Aggregate { sized: true }; - let index = V::new(0); + let index = VariantIdx::new(0); for field in &variants[index] { - assert!(field.is_sized()); - align = align.max(field.align); + assert!(field.0.is_sized()); + align = align.max(field.align()); // If all non-ZST fields have the same ABI, forward this ABI - if optimize && !field.is_zst() { + if optimize && !field.0.is_zst() { // Discard valid range information and allow undef - let field_abi = match field.abi { + let field_abi = match field.abi() { Abi::Scalar(x) => Abi::Scalar(x.to_union()), Abi::ScalarPair(x, y) => Abi::ScalarPair(x.to_union(), y.to_union()), Abi::Vector { element: x, count } => { @@ -926,7 +922,7 @@ pub trait LayoutCalculator { } } - size = cmp::max(size, field.size); + size = cmp::max(size, field.size()); } if let Some(pack) = repr.pack { diff --git a/compiler/rustc_abi/src/lib.rs b/compiler/rustc_abi/src/lib.rs index f4cb459f3..39574ca55 100644 --- a/compiler/rustc_abi/src/lib.rs +++ b/compiler/rustc_abi/src/lib.rs @@ -8,6 +8,7 @@ use std::ops::{Add, AddAssign, Mul, RangeInclusive, Sub}; use std::str::FromStr; use bitflags::bitflags; +use rustc_data_structures::intern::Interned; #[cfg(feature = "nightly")] use rustc_data_structures::stable_hasher::StableOrd; use rustc_index::vec::{Idx, IndexVec}; @@ -170,7 +171,9 @@ pub struct TargetDataLayout { pub instruction_address_space: AddressSpace, - /// Minimum size of #[repr(C)] enums (default I32 bits) + /// Minimum size of #[repr(C)] enums (default c_int::BITS, usually 32) + /// Note: This isn't in LLVM's data layout string, it is `short_enum` + /// so the only valid spec for LLVM is c_int::BITS or 8 pub c_enum_min_size: Integer, } @@ -267,6 +270,9 @@ impl TargetDataLayout { ["a", ref a @ ..] => dl.aggregate_align = align(a, "a")?, ["f32", ref a @ ..] => dl.f32_align = align(a, "f32")?, ["f64", ref a @ ..] => dl.f64_align = align(a, "f64")?, + // FIXME(erikdesjardins): we should be parsing nonzero address spaces + // this will require replacing TargetDataLayout::{pointer_size,pointer_align} + // with e.g. `fn pointer_size_in(AddressSpace)` [p @ "p", s, ref a @ ..] | [p @ "p0", s, ref a @ ..] => { dl.pointer_size = size(s, p)?; dl.pointer_align = align(a, p)?; @@ -861,7 +867,7 @@ pub enum Primitive { Int(Integer, bool), F32, F64, - Pointer, + Pointer(AddressSpace), } impl Primitive { @@ -872,7 +878,10 @@ impl Primitive { Int(i, _) => i.size(), F32 => Size::from_bits(32), F64 => Size::from_bits(64), - Pointer => dl.pointer_size, + // FIXME(erikdesjardins): ignoring address space is technically wrong, pointers in + // different address spaces can have different sizes + // (but TargetDataLayout doesn't currently parse that part of the DL string) + Pointer(_) => dl.pointer_size, } } @@ -883,26 +892,12 @@ impl Primitive { Int(i, _) => i.align(dl), F32 => dl.f32_align, F64 => dl.f64_align, - Pointer => dl.pointer_align, + // FIXME(erikdesjardins): ignoring address space is technically wrong, pointers in + // different address spaces can have different alignments + // (but TargetDataLayout doesn't currently parse that part of the DL string) + Pointer(_) => dl.pointer_align, } } - - // FIXME(eddyb) remove, it's trivial thanks to `matches!`. - #[inline] - pub fn is_float(self) -> bool { - matches!(self, F32 | F64) - } - - // FIXME(eddyb) remove, it's completely unused. - #[inline] - pub fn is_int(self) -> bool { - matches!(self, Int(..)) - } - - #[inline] - pub fn is_ptr(self) -> bool { - matches!(self, Pointer) - } } /// Inclusive wrap-around range of valid values, that is, if @@ -1188,7 +1183,8 @@ impl FieldsShape { /// An identifier that specifies the address space that some operation /// should operate on. Special address spaces have an effect on code generation, /// depending on the target and the address spaces it implements. -#[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord)] +#[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)] +#[cfg_attr(feature = "nightly", derive(HashStable_Generic))] pub struct AddressSpace(pub u32); impl AddressSpace { @@ -1257,9 +1253,9 @@ impl Abi { #[derive(PartialEq, Eq, Hash, Clone, Debug)] #[cfg_attr(feature = "nightly", derive(HashStable_Generic))] -pub enum Variants { +pub enum Variants { /// Single enum variants, structs/tuples, unions, and all non-ADTs. - Single { index: V }, + Single { index: VariantIdx }, /// Enum-likes with more than one inhabited variant: each variant comes with /// a *discriminant* (usually the same as the variant index but the user can @@ -1269,15 +1265,15 @@ pub enum Variants { /// For enums, the tag is the sole field of the layout. Multiple { tag: Scalar, - tag_encoding: TagEncoding, + tag_encoding: TagEncoding, tag_field: usize, - variants: IndexVec>, + variants: IndexVec, }, } #[derive(PartialEq, Eq, Hash, Clone, Debug)] #[cfg_attr(feature = "nightly", derive(HashStable_Generic))] -pub enum TagEncoding { +pub enum TagEncoding { /// The tag directly stores the discriminant, but possibly with a smaller layout /// (so converting the tag to the discriminant can require sign extension). Direct, @@ -1292,7 +1288,11 @@ pub enum TagEncoding { /// For example, `Option<(usize, &T)>` is represented such that /// `None` has a null pointer for the second tuple field, and /// `Some` is the identity function (with a non-null reference). - Niche { untagged_variant: V, niche_variants: RangeInclusive, niche_start: u128 }, + Niche { + untagged_variant: VariantIdx, + niche_variants: RangeInclusive, + niche_start: u128, + }, } #[derive(Clone, Copy, PartialEq, Eq, Hash, Debug)] @@ -1379,9 +1379,14 @@ impl Niche { } } +rustc_index::newtype_index! { + #[derive(HashStable_Generic)] + pub struct VariantIdx {} +} + #[derive(PartialEq, Eq, Hash, Clone)] #[cfg_attr(feature = "nightly", derive(HashStable_Generic))] -pub struct LayoutS { +pub struct LayoutS { /// Says where the fields are located within the layout. pub fields: FieldsShape, @@ -1392,7 +1397,7 @@ pub struct LayoutS { /// /// To access all fields of this layout, both `fields` and the fields of the active variant /// must be taken into account. - pub variants: Variants, + pub variants: Variants, /// The `abi` defines how this data is passed between functions, and it defines /// value restrictions via `valid_range`. @@ -1411,13 +1416,13 @@ pub struct LayoutS { pub size: Size, } -impl LayoutS { +impl LayoutS { pub fn scalar(cx: &C, scalar: Scalar) -> Self { let largest_niche = Niche::from_scalar(cx, Size::ZERO, scalar); let size = scalar.size(cx); let align = scalar.align(cx); LayoutS { - variants: Variants::Single { index: V::new(0) }, + variants: Variants::Single { index: VariantIdx::new(0) }, fields: FieldsShape::Primitive, abi: Abi::Scalar(scalar), largest_niche, @@ -1427,7 +1432,7 @@ impl LayoutS { } } -impl fmt::Debug for LayoutS { +impl fmt::Debug for LayoutS { fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { // This is how `Layout` used to print before it become // `Interned`. We print it like this to avoid having to update @@ -1444,42 +1449,63 @@ impl fmt::Debug for LayoutS { } } -#[derive(Copy, Clone, PartialEq, Eq, Debug)] -pub enum PointerKind { - /// Most general case, we know no restrictions to tell LLVM. - SharedMutable, +#[derive(Copy, Clone, PartialEq, Eq, Hash, HashStable_Generic)] +#[rustc_pass_by_value] +pub struct Layout<'a>(pub Interned<'a, LayoutS>); + +impl<'a> fmt::Debug for Layout<'a> { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + // See comment on `::fmt` above. + self.0.0.fmt(f) + } +} - /// `&T` where `T` contains no `UnsafeCell`, is `dereferenceable`, `noalias` and `readonly`. - Frozen, +impl<'a> Layout<'a> { + pub fn fields(self) -> &'a FieldsShape { + &self.0.0.fields + } - /// `&mut T` which is `dereferenceable` and `noalias` but not `readonly`. - UniqueBorrowed, + pub fn variants(self) -> &'a Variants { + &self.0.0.variants + } - /// `&mut !Unpin`, which is `dereferenceable` but neither `noalias` nor `readonly`. - UniqueBorrowedPinned, + pub fn abi(self) -> Abi { + self.0.0.abi + } + + pub fn largest_niche(self) -> Option { + self.0.0.largest_niche + } + + pub fn align(self) -> AbiAndPrefAlign { + self.0.0.align + } - /// `Box`, which is `noalias` (even on return types, unlike the above) but neither `readonly` - /// nor `dereferenceable`. - UniqueOwned, + pub fn size(self) -> Size { + self.0.0.size + } +} + +#[derive(Copy, Clone, PartialEq, Eq, Debug)] +pub enum PointerKind { + /// Shared reference. `frozen` indicates the absence of any `UnsafeCell`. + SharedRef { frozen: bool }, + /// Mutable reference. `unpin` indicates the absence of any pinned data. + MutableRef { unpin: bool }, + /// Box. `unpin` indicates the absence of any pinned data. + Box { unpin: bool }, } +/// Note that this information is advisory only, and backends are free to ignore it. +/// It can only be used to encode potential optimizations, but no critical information. #[derive(Copy, Clone, Debug)] pub struct PointeeInfo { pub size: Size, pub align: Align, pub safe: Option, - pub address_space: AddressSpace, -} - -/// Used in `might_permit_raw_init` to indicate the kind of initialisation -/// that is checked to be valid -#[derive(Copy, Clone, Debug, PartialEq, Eq)] -pub enum InitKind { - Zero, - UninitMitigated0x01Fill, } -impl LayoutS { +impl LayoutS { /// Returns `true` if the layout corresponds to an unsized type. pub fn is_unsized(&self) -> bool { self.abi.is_unsized() -- cgit v1.2.3