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Change tag_field to FieldIdx in Variants::Multiple

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It was already available as a generic parameter anyway, and it's not like we'll ever put a tag in the 5-billionth field.
This commit is contained in:
Scott McMurray
2025-06-03 23:42:21 -07:00
parent 792fc2b033
commit ee9901e65c
14 changed files with 33 additions and 31 deletions
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6
compiler/rustc_codegen_cranelift/src/discriminant.rs
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@@ -28,7 +28,7 @@ pub(crate) fn codegen_set_discriminant<'tcx>(
tag_encoding: TagEncoding::Direct,
variants: _,
} => {
let ptr = place.place_field(fx, FieldIdx::new(tag_field));
let ptr = place.place_field(fx, tag_field);
let to = layout.ty.discriminant_for_variant(fx.tcx, variant_index).unwrap().val;
let to = match ptr.layout().ty.kind() {
ty::Uint(UintTy::U128) | ty::Int(IntTy::I128) => {
@@ -53,7 +53,7 @@ pub(crate) fn codegen_set_discriminant<'tcx>(
variants: _,
} => {
if variant_index != untagged_variant {
let niche = place.place_field(fx, FieldIdx::new(tag_field));
let niche = place.place_field(fx, tag_field);
let niche_type = fx.clif_type(niche.layout().ty).unwrap();
let niche_value = variant_index.as_u32() - niche_variants.start().as_u32();
let niche_value = (niche_value as u128).wrapping_add(niche_start);
@@ -118,7 +118,7 @@ pub(crate) fn codegen_get_discriminant<'tcx>(
let cast_to = fx.clif_type(dest_layout.ty).unwrap();
// Read the tag/niche-encoded discriminant from memory.
let tag = value.value_field(fx, FieldIdx::new(tag_field));
let tag = value.value_field(fx, tag_field);
let tag = tag.load_scalar(fx);
// Decode the discriminant (specifically if it's niche-encoded).