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use rustc_ast::Mutability;
use rustc_middle::mir;
use rustc_middle::ty;
use rustc_middle::ty::layout::{LayoutOf, PrimitiveExt, TyAndLayout};
use rustc_target::abi::{self, Abi, Align, HasDataLayout, Size, TagEncoding, VariantIdx};
use super::{
alloc_range, mir_assign_valid_types, AllocId, AllocRef, AllocRefMut, CheckInAllocMsg,
ConstAlloc, ImmTy, Immediate, InterpCx, InterpResult, Machine, MemoryKind, OpTy, Operand,
Pointer, Provenance, Scalar,
};
#[derive(Copy, Clone, Hash, PartialEq, Eq, Debug)]
pub enum MemPlaceMeta<Prov: Provenance = AllocId> {
Meta(Scalar<Prov>),
None,
}
impl<Prov: Provenance> MemPlaceMeta<Prov> {
pub fn unwrap_meta(self) -> Scalar<Prov> {
match self {
Self::Meta(s) => s,
Self::None => {
bug!("expected wide pointer extra data (e.g. slice length or trait object vtable)")
}
}
}
pub fn has_meta(self) -> bool {
match self {
Self::Meta(_) => true,
Self::None => false,
}
}
}
#[derive(Copy, Clone, Hash, PartialEq, Eq, Debug)]
pub struct MemPlace<Prov: Provenance = AllocId> {
pub ptr: Pointer<Option<Prov>>,
pub meta: MemPlaceMeta<Prov>,
}
#[derive(Copy, Clone, Hash, Eq, PartialEq, Debug)]
pub struct MPlaceTy<'tcx, Prov: Provenance = AllocId> {
mplace: MemPlace<Prov>,
pub layout: TyAndLayout<'tcx>,
pub align: Align,
}
#[derive(Copy, Clone, Debug)]
pub enum Place<Prov: Provenance = AllocId> {
Ptr(MemPlace<Prov>),
Local { frame: usize, local: mir::Local },
}
#[derive(Clone, Debug)]
pub struct PlaceTy<'tcx, Prov: Provenance = AllocId> {
place: Place<Prov>, pub layout: TyAndLayout<'tcx>,
pub align: Align,
}
impl<'tcx, Prov: Provenance> std::ops::Deref for PlaceTy<'tcx, Prov> {
type Target = Place<Prov>;
#[inline(always)]
fn deref(&self) -> &Place<Prov> {
&self.place
}
}
impl<'tcx, Prov: Provenance> std::ops::Deref for MPlaceTy<'tcx, Prov> {
type Target = MemPlace<Prov>;
#[inline(always)]
fn deref(&self) -> &MemPlace<Prov> {
&self.mplace
}
}
impl<'tcx, Prov: Provenance> From<MPlaceTy<'tcx, Prov>> for PlaceTy<'tcx, Prov> {
#[inline(always)]
fn from(mplace: MPlaceTy<'tcx, Prov>) -> Self {
PlaceTy { place: Place::Ptr(*mplace), layout: mplace.layout, align: mplace.align }
}
}
impl<'tcx, Prov: Provenance> From<&'_ MPlaceTy<'tcx, Prov>> for PlaceTy<'tcx, Prov> {
#[inline(always)]
fn from(mplace: &MPlaceTy<'tcx, Prov>) -> Self {
PlaceTy { place: Place::Ptr(**mplace), layout: mplace.layout, align: mplace.align }
}
}
impl<'tcx, Prov: Provenance> From<&'_ mut MPlaceTy<'tcx, Prov>> for PlaceTy<'tcx, Prov> {
#[inline(always)]
fn from(mplace: &mut MPlaceTy<'tcx, Prov>) -> Self {
PlaceTy { place: Place::Ptr(**mplace), layout: mplace.layout, align: mplace.align }
}
}
impl<Prov: Provenance> MemPlace<Prov> {
#[inline(always)]
pub fn from_ptr(ptr: Pointer<Option<Prov>>) -> Self {
MemPlace { ptr, meta: MemPlaceMeta::None }
}
pub fn map_provenance(self, f: impl FnOnce(Option<Prov>) -> Option<Prov>) -> Self {
MemPlace { ptr: self.ptr.map_provenance(f), ..self }
}
#[inline(always)]
pub fn to_ref(self, cx: &impl HasDataLayout) -> Immediate<Prov> {
match self.meta {
MemPlaceMeta::None => Immediate::from(Scalar::from_maybe_pointer(self.ptr, cx)),
MemPlaceMeta::Meta(meta) => {
Immediate::ScalarPair(Scalar::from_maybe_pointer(self.ptr, cx).into(), meta.into())
}
}
}
#[inline]
pub fn offset_with_meta<'tcx>(
self,
offset: Size,
meta: MemPlaceMeta<Prov>,
cx: &impl HasDataLayout,
) -> InterpResult<'tcx, Self> {
Ok(MemPlace { ptr: self.ptr.offset(offset, cx)?, meta })
}
}
impl<Prov: Provenance> Place<Prov> {
#[inline]
#[cfg_attr(debug_assertions, track_caller)] pub fn assert_local(&self) -> (usize, mir::Local) {
match self {
Place::Local { frame, local } => (*frame, *local),
_ => bug!("assert_local: expected Place::Local, got {:?}", self),
}
}
}
impl<'tcx, Prov: Provenance> MPlaceTy<'tcx, Prov> {
#[inline]
pub fn fake_alloc_zst(layout: TyAndLayout<'tcx>) -> Self {
assert!(layout.is_zst());
let align = layout.align.abi;
let ptr = Pointer::from_addr(align.bytes()); MPlaceTy { mplace: MemPlace { ptr, meta: MemPlaceMeta::None }, layout, align }
}
#[inline]
pub fn offset_with_meta(
&self,
offset: Size,
meta: MemPlaceMeta<Prov>,
layout: TyAndLayout<'tcx>,
cx: &impl HasDataLayout,
) -> InterpResult<'tcx, Self> {
Ok(MPlaceTy {
mplace: self.mplace.offset_with_meta(offset, meta, cx)?,
align: self.align.restrict_for_offset(offset),
layout,
})
}
pub fn offset(
&self,
offset: Size,
layout: TyAndLayout<'tcx>,
cx: &impl HasDataLayout,
) -> InterpResult<'tcx, Self> {
assert!(!layout.is_unsized());
self.offset_with_meta(offset, MemPlaceMeta::None, layout, cx)
}
#[inline]
pub fn from_aligned_ptr(ptr: Pointer<Option<Prov>>, layout: TyAndLayout<'tcx>) -> Self {
MPlaceTy { mplace: MemPlace::from_ptr(ptr), layout, align: layout.align.abi }
}
#[inline]
pub fn from_aligned_ptr_with_meta(
ptr: Pointer<Option<Prov>>,
layout: TyAndLayout<'tcx>,
meta: MemPlaceMeta<Prov>,
) -> Self {
let mut mplace = MemPlace::from_ptr(ptr);
mplace.meta = meta;
MPlaceTy { mplace, layout, align: layout.align.abi }
}
#[inline]
pub(crate) fn len(&self, cx: &impl HasDataLayout) -> InterpResult<'tcx, u64> {
if self.layout.is_unsized() {
match self.layout.ty.kind() {
ty::Slice(..) | ty::Str => self.mplace.meta.unwrap_meta().to_machine_usize(cx),
_ => bug!("len not supported on unsized type {:?}", self.layout.ty),
}
} else {
match self.layout.fields {
abi::FieldsShape::Array { count, .. } => Ok(count),
_ => bug!("len not supported on sized type {:?}", self.layout.ty),
}
}
}
#[inline]
pub(super) fn vtable(&self) -> Scalar<Prov> {
match self.layout.ty.kind() {
ty::Dynamic(..) => self.mplace.meta.unwrap_meta(),
_ => bug!("vtable not supported on type {:?}", self.layout.ty),
}
}
}
impl<'tcx, Prov: Provenance> OpTy<'tcx, Prov> {
#[inline(always)]
pub fn try_as_mplace(&self) -> Result<MPlaceTy<'tcx, Prov>, ImmTy<'tcx, Prov>> {
match **self {
Operand::Indirect(mplace) => {
Ok(MPlaceTy { mplace, layout: self.layout, align: self.align.unwrap() })
}
Operand::Immediate(imm) => Err(ImmTy::from_immediate(imm, self.layout)),
}
}
#[inline(always)]
#[cfg_attr(debug_assertions, track_caller)] pub fn assert_mem_place(&self) -> MPlaceTy<'tcx, Prov> {
self.try_as_mplace().unwrap()
}
}
impl<'tcx, Prov: Provenance> PlaceTy<'tcx, Prov> {
#[inline]
pub fn try_as_mplace(&self) -> Result<MPlaceTy<'tcx, Prov>, (usize, mir::Local)> {
match **self {
Place::Ptr(mplace) => Ok(MPlaceTy { mplace, layout: self.layout, align: self.align }),
Place::Local { frame, local } => Err((frame, local)),
}
}
#[inline(always)]
#[cfg_attr(debug_assertions, track_caller)] pub fn assert_mem_place(self) -> MPlaceTy<'tcx, Prov> {
self.try_as_mplace().unwrap()
}
}
impl<'mir, 'tcx: 'mir, Prov, M> InterpCx<'mir, 'tcx, M>
where
Prov: Provenance + 'static,
M: Machine<'mir, 'tcx, Provenance = Prov>,
{
pub fn ref_to_mplace(
&self,
val: &ImmTy<'tcx, M::Provenance>,
) -> InterpResult<'tcx, MPlaceTy<'tcx, M::Provenance>> {
let pointee_type =
val.layout.ty.builtin_deref(true).expect("`ref_to_mplace` called on non-ptr type").ty;
let layout = self.layout_of(pointee_type)?;
let (ptr, meta) = match **val {
Immediate::Scalar(ptr) => (ptr, MemPlaceMeta::None),
Immediate::ScalarPair(ptr, meta) => (ptr, MemPlaceMeta::Meta(meta)),
Immediate::Uninit => throw_ub!(InvalidUninitBytes(None)),
};
let mplace = MemPlace { ptr: ptr.to_pointer(self)?, meta };
let align = layout.align.abi;
Ok(MPlaceTy { mplace, layout, align })
}
#[instrument(skip(self), level = "debug")]
pub fn deref_operand(
&self,
src: &OpTy<'tcx, M::Provenance>,
) -> InterpResult<'tcx, MPlaceTy<'tcx, M::Provenance>> {
let val = self.read_immediate(src)?;
trace!("deref to {} on {:?}", val.layout.ty, *val);
if val.layout.ty.is_box() {
bug!("dereferencing {:?}", val.layout.ty);
}
let mplace = self.ref_to_mplace(&val)?;
self.check_mplace_access(mplace, CheckInAllocMsg::DerefTest)?;
Ok(mplace)
}
#[inline]
pub(super) fn get_place_alloc(
&self,
place: &MPlaceTy<'tcx, M::Provenance>,
) -> InterpResult<'tcx, Option<AllocRef<'_, 'tcx, M::Provenance, M::AllocExtra>>> {
assert!(!place.layout.is_unsized());
assert!(!place.meta.has_meta());
let size = place.layout.size;
self.get_ptr_alloc(place.ptr, size, place.align)
}
#[inline]
pub(super) fn get_place_alloc_mut(
&mut self,
place: &MPlaceTy<'tcx, M::Provenance>,
) -> InterpResult<'tcx, Option<AllocRefMut<'_, 'tcx, M::Provenance, M::AllocExtra>>> {
assert!(!place.layout.is_unsized());
assert!(!place.meta.has_meta());
let size = place.layout.size;
self.get_ptr_alloc_mut(place.ptr, size, place.align)
}
fn check_mplace_access(
&self,
mplace: MPlaceTy<'tcx, M::Provenance>,
msg: CheckInAllocMsg,
) -> InterpResult<'tcx> {
let (size, align) = self
.size_and_align_of_mplace(&mplace)?
.unwrap_or((mplace.layout.size, mplace.layout.align.abi));
assert!(mplace.align <= align, "dynamic alignment less strict than static one?");
let align = M::enforce_alignment(self).then_some(align);
self.check_ptr_access_align(mplace.ptr, size, align.unwrap_or(Align::ONE), msg)?;
Ok(())
}
pub fn mplace_to_simd(
&self,
mplace: &MPlaceTy<'tcx, M::Provenance>,
) -> InterpResult<'tcx, (MPlaceTy<'tcx, M::Provenance>, u64)> {
let (len, e_ty) = mplace.layout.ty.simd_size_and_type(*self.tcx);
let array = self.tcx.mk_array(e_ty, len);
let layout = self.layout_of(array)?;
assert_eq!(layout.size, mplace.layout.size);
Ok((MPlaceTy { layout, ..*mplace }, len))
}
pub fn place_to_simd(
&mut self,
place: &PlaceTy<'tcx, M::Provenance>,
) -> InterpResult<'tcx, (MPlaceTy<'tcx, M::Provenance>, u64)> {
let mplace = self.force_allocation(place)?;
self.mplace_to_simd(&mplace)
}
pub fn local_to_place(
&self,
frame: usize,
local: mir::Local,
) -> InterpResult<'tcx, PlaceTy<'tcx, M::Provenance>> {
let layout = self.layout_of_local(&self.stack()[frame], local, None)?;
let place = Place::Local { frame, local };
Ok(PlaceTy { place, layout, align: layout.align.abi })
}
#[instrument(skip(self), level = "debug")]
pub fn eval_place(
&mut self,
mir_place: mir::Place<'tcx>,
) -> InterpResult<'tcx, PlaceTy<'tcx, M::Provenance>> {
let mut place = self.local_to_place(self.frame_idx(), mir_place.local)?;
for elem in mir_place.projection.iter() {
place = self.place_projection(&place, elem)?
}
trace!("{:?}", self.dump_place(place.place));
debug_assert!(
mir_assign_valid_types(
*self.tcx,
self.param_env,
self.layout_of(self.subst_from_current_frame_and_normalize_erasing_regions(
mir_place.ty(&self.frame().body.local_decls, *self.tcx).ty
)?)?,
place.layout,
),
"eval_place of a MIR place with type {:?} produced an interpreter place with type {:?}",
mir_place.ty(&self.frame().body.local_decls, *self.tcx).ty,
place.layout.ty,
);
Ok(place)
}
#[inline(always)]
#[instrument(skip(self), level = "debug")]
pub fn write_immediate(
&mut self,
src: Immediate<M::Provenance>,
dest: &PlaceTy<'tcx, M::Provenance>,
) -> InterpResult<'tcx> {
self.write_immediate_no_validate(src, dest)?;
if M::enforce_validity(self) {
self.validate_operand(&self.place_to_op(dest)?)?;
}
Ok(())
}
#[inline(always)]
pub fn write_scalar(
&mut self,
val: impl Into<Scalar<M::Provenance>>,
dest: &PlaceTy<'tcx, M::Provenance>,
) -> InterpResult<'tcx> {
self.write_immediate(Immediate::Scalar(val.into()), dest)
}
#[inline(always)]
pub fn write_pointer(
&mut self,
ptr: impl Into<Pointer<Option<M::Provenance>>>,
dest: &PlaceTy<'tcx, M::Provenance>,
) -> InterpResult<'tcx> {
self.write_scalar(Scalar::from_maybe_pointer(ptr.into(), self), dest)
}
fn write_immediate_no_validate(
&mut self,
src: Immediate<M::Provenance>,
dest: &PlaceTy<'tcx, M::Provenance>,
) -> InterpResult<'tcx> {
assert!(!dest.layout.is_unsized(), "Cannot write unsized data");
trace!("write_immediate: {:?} <- {:?}: {}", *dest, src, dest.layout.ty);
let mplace = match dest.place {
Place::Local { frame, local } => {
match M::access_local_mut(self, frame, local)? {
Operand::Immediate(local) => {
*local = src;
return Ok(());
}
Operand::Indirect(mplace) => {
*mplace
}
}
}
Place::Ptr(mplace) => mplace, };
self.write_immediate_to_mplace_no_validate(src, dest.layout, dest.align, mplace)
}
fn write_immediate_to_mplace_no_validate(
&mut self,
value: Immediate<M::Provenance>,
layout: TyAndLayout<'tcx>,
align: Align,
dest: MemPlace<M::Provenance>,
) -> InterpResult<'tcx> {
let tcx = *self.tcx;
let Some(mut alloc) = self.get_place_alloc_mut(&MPlaceTy { mplace: dest, layout, align })? else {
return Ok(());
};
match value {
Immediate::Scalar(scalar) => {
let Abi::Scalar(s) = layout.abi else { span_bug!(
self.cur_span(),
"write_immediate_to_mplace: invalid Scalar layout: {layout:#?}",
)
};
let size = s.size(&tcx);
assert_eq!(size, layout.size, "abi::Scalar size does not match layout size");
alloc.write_scalar(alloc_range(Size::ZERO, size), scalar)
}
Immediate::ScalarPair(a_val, b_val) => {
let Abi::ScalarPair(a, b) = layout.abi else { span_bug!(
self.cur_span(),
"write_immediate_to_mplace: invalid ScalarPair layout: {:#?}",
layout
)
};
let (a_size, b_size) = (a.size(&tcx), b.size(&tcx));
let b_offset = a_size.align_to(b.align(&tcx).abi);
assert!(b_offset.bytes() > 0); alloc.write_scalar(alloc_range(Size::ZERO, a_size), a_val)?;
alloc.write_scalar(alloc_range(b_offset, b_size), b_val)
}
Immediate::Uninit => alloc.write_uninit(),
}
}
pub fn write_uninit(&mut self, dest: &PlaceTy<'tcx, M::Provenance>) -> InterpResult<'tcx> {
let mplace = match dest.try_as_mplace() {
Ok(mplace) => mplace,
Err((frame, local)) => {
match M::access_local_mut(self, frame, local)? {
Operand::Immediate(local) => {
*local = Immediate::Uninit;
return Ok(());
}
Operand::Indirect(mplace) => {
MPlaceTy { mplace: *mplace, layout: dest.layout, align: dest.align }
}
}
}
};
let Some(mut alloc) = self.get_place_alloc_mut(&mplace)? else {
return Ok(());
};
alloc.write_uninit()?;
Ok(())
}
#[inline(always)]
#[instrument(skip(self), level = "debug")]
pub fn copy_op(
&mut self,
src: &OpTy<'tcx, M::Provenance>,
dest: &PlaceTy<'tcx, M::Provenance>,
allow_transmute: bool,
) -> InterpResult<'tcx> {
self.copy_op_no_validate(src, dest, allow_transmute)?;
if M::enforce_validity(self) {
self.validate_operand(&self.place_to_op(dest)?)?;
}
Ok(())
}
#[instrument(skip(self), level = "debug")]
fn copy_op_no_validate(
&mut self,
src: &OpTy<'tcx, M::Provenance>,
dest: &PlaceTy<'tcx, M::Provenance>,
allow_transmute: bool,
) -> InterpResult<'tcx> {
let layout_compat =
mir_assign_valid_types(*self.tcx, self.param_env, src.layout, dest.layout);
if !allow_transmute && !layout_compat {
span_bug!(
self.cur_span(),
"type mismatch when copying!\nsrc: {:?},\ndest: {:?}",
src.layout.ty,
dest.layout.ty,
);
}
let src = match self.read_immediate_raw(src)? {
Ok(src_val) => {
assert!(!src.layout.is_unsized(), "cannot copy unsized immediates");
assert!(
!dest.layout.is_unsized(),
"the src is sized, so the dest must also be sized"
);
assert_eq!(src.layout.size, dest.layout.size);
return if layout_compat {
self.write_immediate_no_validate(*src_val, dest)
} else {
let dest_mem = self.force_allocation(dest)?;
self.write_immediate_to_mplace_no_validate(
*src_val,
src.layout,
dest_mem.align,
*dest_mem,
)
};
}
Err(mplace) => mplace,
};
trace!("copy_op: {:?} <- {:?}: {}", *dest, src, dest.layout.ty);
let dest = self.force_allocation(&dest)?;
let Some((dest_size, _)) = self.size_and_align_of_mplace(&dest)? else {
span_bug!(self.cur_span(), "copy_op needs (dynamically) sized values")
};
if cfg!(debug_assertions) {
let src_size = self.size_and_align_of_mplace(&src)?.unwrap().0;
assert_eq!(src_size, dest_size, "Cannot copy differently-sized data");
} else {
assert_eq!(src.layout.size, dest.layout.size);
}
self.mem_copy(
src.ptr, src.align, dest.ptr, dest.align, dest_size, false,
)
}
#[instrument(skip(self), level = "debug")]
pub fn force_allocation(
&mut self,
place: &PlaceTy<'tcx, M::Provenance>,
) -> InterpResult<'tcx, MPlaceTy<'tcx, M::Provenance>> {
let mplace = match place.place {
Place::Local { frame, local } => {
match M::access_local_mut(self, frame, local)? {
&mut Operand::Immediate(local_val) => {
let local_layout =
self.layout_of_local(&self.stack()[frame], local, None)?;
if local_layout.is_unsized() {
throw_unsup_format!("unsized locals are not supported");
}
let mplace = *self.allocate(local_layout, MemoryKind::Stack)?;
if !matches!(local_val, Immediate::Uninit) {
self.write_immediate_to_mplace_no_validate(
local_val,
local_layout,
local_layout.align.abi,
mplace,
)?;
}
*M::access_local_mut(self, frame, local).unwrap() =
Operand::Indirect(mplace);
mplace
}
&mut Operand::Indirect(mplace) => mplace, }
}
Place::Ptr(mplace) => mplace,
};
Ok(MPlaceTy { mplace, layout: place.layout, align: place.align })
}
pub fn allocate(
&mut self,
layout: TyAndLayout<'tcx>,
kind: MemoryKind<M::MemoryKind>,
) -> InterpResult<'tcx, MPlaceTy<'tcx, M::Provenance>> {
assert!(!layout.is_unsized());
let ptr = self.allocate_ptr(layout.size, layout.align.abi, kind)?;
Ok(MPlaceTy::from_aligned_ptr(ptr.into(), layout))
}
pub fn allocate_str(
&mut self,
str: &str,
kind: MemoryKind<M::MemoryKind>,
mutbl: Mutability,
) -> MPlaceTy<'tcx, M::Provenance> {
let ptr = self.allocate_bytes_ptr(str.as_bytes(), Align::ONE, kind, mutbl);
let meta = Scalar::from_machine_usize(u64::try_from(str.len()).unwrap(), self);
let mplace = MemPlace { ptr: ptr.into(), meta: MemPlaceMeta::Meta(meta) };
let ty = self.tcx.mk_ref(
self.tcx.lifetimes.re_static,
ty::TypeAndMut { ty: self.tcx.types.str_, mutbl },
);
let layout = self.layout_of(ty).unwrap();
MPlaceTy { mplace, layout, align: layout.align.abi }
}
#[instrument(skip(self), level = "debug")]
pub fn write_discriminant(
&mut self,
variant_index: VariantIdx,
dest: &PlaceTy<'tcx, M::Provenance>,
) -> InterpResult<'tcx> {
match dest.layout.ty.kind() {
ty::Adt(adt, _) => assert!(adt.is_enum()),
ty::Generator(..) => {}
_ => span_bug!(
self.cur_span(),
"write_discriminant called on non-variant-type (neither enum nor generator)"
),
}
if dest.layout.for_variant(self, variant_index).abi.is_uninhabited() {
throw_ub!(UninhabitedEnumVariantWritten)
}
match dest.layout.variants {
abi::Variants::Single { index } => {
assert_eq!(index, variant_index);
}
abi::Variants::Multiple {
tag_encoding: TagEncoding::Direct,
tag: tag_layout,
tag_field,
..
} => {
let discr_val =
dest.layout.ty.discriminant_for_variant(*self.tcx, variant_index).unwrap().val;
let size = tag_layout.size(self);
let tag_val = size.truncate(discr_val);
let tag_dest = self.place_field(dest, tag_field)?;
self.write_scalar(Scalar::from_uint(tag_val, size), &tag_dest)?;
}
abi::Variants::Multiple {
tag_encoding:
TagEncoding::Niche { untagged_variant, ref niche_variants, niche_start },
tag: tag_layout,
tag_field,
..
} => {
if variant_index != untagged_variant {
let variants_start = niche_variants.start().as_u32();
let variant_index_relative = variant_index
.as_u32()
.checked_sub(variants_start)
.expect("overflow computing relative variant idx");
let tag_layout = self.layout_of(tag_layout.primitive().to_int_ty(*self.tcx))?;
let niche_start_val = ImmTy::from_uint(niche_start, tag_layout);
let variant_index_relative_val =
ImmTy::from_uint(variant_index_relative, tag_layout);
let tag_val = self.binary_op(
mir::BinOp::Add,
&variant_index_relative_val,
&niche_start_val,
)?;
let niche_dest = self.place_field(dest, tag_field)?;
self.write_immediate(*tag_val, &niche_dest)?;
}
}
}
Ok(())
}
pub fn raw_const_to_mplace(
&self,
raw: ConstAlloc<'tcx>,
) -> InterpResult<'tcx, MPlaceTy<'tcx, M::Provenance>> {
let _ = self.tcx.global_alloc(raw.alloc_id);
let ptr = self.global_base_pointer(Pointer::from(raw.alloc_id))?;
let layout = self.layout_of(raw.ty)?;
Ok(MPlaceTy::from_aligned_ptr(ptr.into(), layout))
}
pub(super) fn unpack_dyn_trait(
&self,
mplace: &MPlaceTy<'tcx, M::Provenance>,
) -> InterpResult<'tcx, MPlaceTy<'tcx, M::Provenance>> {
let vtable = mplace.vtable().to_pointer(self)?; let (ty, _) = self.get_ptr_vtable(vtable)?;
let layout = self.layout_of(ty)?;
let mplace = MPlaceTy {
mplace: MemPlace { meta: MemPlaceMeta::None, ..**mplace },
layout,
align: layout.align.abi,
};
Ok(mplace)
}
}
#[cfg(all(target_arch = "x86_64", target_pointer_width = "64"))]
mod size_asserts {
use super::*;
use rustc_data_structures::static_assert_size;
static_assert_size!(MemPlaceMeta, 24);
static_assert_size!(MemPlace, 40);
static_assert_size!(MPlaceTy<'_>, 64);
#[cfg(not(bootstrap))]
static_assert_size!(Place, 40);
#[cfg(not(bootstrap))]
static_assert_size!(PlaceTy<'_>, 64);
}