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-rw-r--r--compiler/rustc_const_eval/src/util/aggregate.rs77
1 files changed, 0 insertions, 77 deletions
diff --git a/compiler/rustc_const_eval/src/util/aggregate.rs b/compiler/rustc_const_eval/src/util/aggregate.rs
deleted file mode 100644
index 10783c5ed..000000000
--- a/compiler/rustc_const_eval/src/util/aggregate.rs
+++ /dev/null
@@ -1,77 +0,0 @@
-use rustc_index::vec::Idx;
-use rustc_middle::mir::*;
-use rustc_middle::ty::{Ty, TyCtxt};
-use rustc_target::abi::VariantIdx;
-
-use std::iter::TrustedLen;
-
-/// Expand `lhs = Rvalue::Aggregate(kind, operands)` into assignments to the fields.
-///
-/// Produces something like
-/// ```ignore (ilustrative)
-/// (lhs as Variant).field0 = arg0; // We only have a downcast if this is an enum
-/// (lhs as Variant).field1 = arg1;
-/// discriminant(lhs) = variant_index; // If lhs is an enum or generator.
-/// ```
-pub fn expand_aggregate<'tcx>(
- orig_lhs: Place<'tcx>,
- operands: impl Iterator<Item = (Operand<'tcx>, Ty<'tcx>)> + TrustedLen,
- kind: AggregateKind<'tcx>,
- source_info: SourceInfo,
- tcx: TyCtxt<'tcx>,
-) -> impl Iterator<Item = Statement<'tcx>> + TrustedLen {
- let mut lhs = orig_lhs;
- let mut set_discriminant = None;
- let active_field_index = match kind {
- AggregateKind::Adt(adt_did, variant_index, _, _, active_field_index) => {
- let adt_def = tcx.adt_def(adt_did);
- if adt_def.is_enum() {
- set_discriminant = Some(Statement {
- kind: StatementKind::SetDiscriminant {
- place: Box::new(orig_lhs),
- variant_index,
- },
- source_info,
- });
- lhs = tcx.mk_place_downcast(orig_lhs, adt_def, variant_index);
- }
- active_field_index
- }
- AggregateKind::Generator(..) => {
- // Right now we only support initializing generators to
- // variant 0 (Unresumed).
- let variant_index = VariantIdx::new(0);
- set_discriminant = Some(Statement {
- kind: StatementKind::SetDiscriminant { place: Box::new(orig_lhs), variant_index },
- source_info,
- });
-
- // Operands are upvars stored on the base place, so no
- // downcast is necessary.
-
- None
- }
- _ => None,
- };
-
- let operands = operands.enumerate().map(move |(i, (op, ty))| {
- let lhs_field = if let AggregateKind::Array(_) = kind {
- let offset = u64::try_from(i).unwrap();
- tcx.mk_place_elem(
- lhs,
- ProjectionElem::ConstantIndex { offset, min_length: offset + 1, from_end: false },
- )
- } else {
- let field = Field::new(active_field_index.unwrap_or(i));
- tcx.mk_place_field(lhs, field, ty)
- };
- Statement {
- source_info,
- kind: StatementKind::Assign(Box::new((lhs_field, Rvalue::Use(op)))),
- }
- });
- [Statement { source_info, kind: StatementKind::Deinit(Box::new(orig_lhs)) }]
- .into_iter()
- .chain(operands)
- .chain(set_discriminant)
-}