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 rustc_middle::ty::layout::{LayoutOf, TyAndLayout};
+use rustc_target::abi::{self, Abi, Align, HasDataLayout, Size, VariantIdx};
use super::{
alloc_range, mir_assign_valid_types, AllocId, AllocRef, AllocRefMut, CheckInAllocMsg,
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);
+ ) -> InterpResult<'tcx, 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) };
ty::TypeAndMut { ty: self.tcx.types.str_, mutbl },
);
let layout = self.layout_of(ty).unwrap();
- MPlaceTy { mplace, layout, align: layout.align.abi }
+ Ok(MPlaceTy { mplace, layout, align: layout.align.abi })
}
- /// Writes the discriminant of the given variant.
- #[instrument(skip(self), level = "debug")]
- pub fn write_discriminant(
+ /// Writes the aggregate to the destination.
+ #[instrument(skip(self), level = "trace")]
+ pub fn write_aggregate(
&mut self,
- variant_index: VariantIdx,
+ kind: &mir::AggregateKind<'tcx>,
+ operands: &[mir::Operand<'tcx>],
dest: &PlaceTy<'tcx, M::Provenance>,
) -> InterpResult<'tcx> {
- // This must be an enum or generator.
- 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)"
- ),
- }
- // Layout computation excludes uninhabited variants from consideration
- // therefore there's no way to represent those variants in the given layout.
- // Essentially, uninhabited variants do not have a tag that corresponds to their
- // discriminant, so we cannot do anything here.
- // When evaluating we will always error before even getting here, but ConstProp 'executes'
- // dead code, so we cannot ICE here.
- 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,
- ..
- } => {
- // No need to validate that the discriminant here because the
- // `TyAndLayout::for_variant()` call earlier already checks the variant is valid.
-
- let discr_val =
- dest.layout.ty.discriminant_for_variant(*self.tcx, variant_index).unwrap().val;
-
- // raw discriminants for enums are isize or bigger during
- // their computation, but the in-memory tag is the smallest possible
- // representation
- 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,
- ..
- } => {
- // No need to validate that the discriminant here because the
- // `TyAndLayout::for_variant()` call earlier already checks the variant is valid.
-
- 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");
- // We need to use machine arithmetic when taking into account `niche_start`:
- // tag_val = variant_index_relative + niche_start_val
- 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,
- )?;
- // Write result.
- let niche_dest = self.place_field(dest, tag_field)?;
- self.write_immediate(*tag_val, &niche_dest)?;
- }
+ self.write_uninit(&dest)?;
+ let (variant_index, variant_dest, active_field_index) = match *kind {
+ mir::AggregateKind::Adt(_, variant_index, _, _, active_field_index) => {
+ let variant_dest = self.place_downcast(&dest, variant_index)?;
+ (variant_index, variant_dest, active_field_index)
}
+ _ => (VariantIdx::from_u32(0), dest.clone(), None),
+ };
+ if active_field_index.is_some() {
+ assert_eq!(operands.len(), 1);
}
-
- Ok(())
+ for (field_index, operand) in operands.iter().enumerate() {
+ let field_index = active_field_index.unwrap_or(field_index);
+ let field_dest = self.place_field(&variant_dest, field_index)?;
+ let op = self.eval_operand(operand, Some(field_dest.layout))?;
+ self.copy_op(&op, &field_dest, /*allow_transmute*/ false)?;
+ }
+ self.write_discriminant(variant_index, &dest)
}
pub fn raw_const_to_mplace(
projects / rust.git / blobdiff