factor getting the discriminant layout to a new method
diff --git a/src/librustc/ty/layout.rs b/src/librustc/ty/layout.rs
index 5ec4754..e52feea 100644
--- a/src/librustc/ty/layout.rs
+++ b/src/librustc/ty/layout.rs
@@ -127,6 +127,7 @@
pub trait PrimitiveExt {
fn to_ty<'tcx>(&self, tcx: TyCtxt<'tcx>) -> Ty<'tcx>;
+ fn to_int_ty<'tcx>(&self, tcx: TyCtxt<'tcx>) -> Ty<'tcx>;
}
impl PrimitiveExt for Primitive {
@@ -138,6 +139,16 @@
Pointer => tcx.mk_mut_ptr(tcx.mk_unit()),
}
}
+
+ /// Return an *integer* type matching this primitive.
+ /// Useful in particular when dealing with enum discriminants.
+ fn to_int_ty(&self, tcx: TyCtxt<'tcx>) -> Ty<'tcx> {
+ match *self {
+ Int(i, signed) => i.to_ty(tcx, signed),
+ Pointer => tcx.types.usize,
+ Float(..) => bug!("floats do not have an int type"),
+ }
+ }
}
/// The first half of a fat pointer.
diff --git a/src/librustc_mir/interpret/operand.rs b/src/librustc_mir/interpret/operand.rs
index 2a0bad2..94fbd4a 100644
--- a/src/librustc_mir/interpret/operand.rs
+++ b/src/librustc_mir/interpret/operand.rs
@@ -5,7 +5,7 @@
use rustc::{mir, ty};
use rustc::ty::layout::{
- self, Size, LayoutOf, TyLayout, HasDataLayout, IntegerExt, VariantIdx,
+ self, Size, LayoutOf, TyLayout, HasDataLayout, IntegerExt, PrimitiveExt, VariantIdx,
};
use rustc::mir::interpret::{
@@ -687,13 +687,7 @@
(dataful_variant.as_u32() as u128, dataful_variant)
},
Ok(raw_discr) => {
- // FIXME: WTF, some discriminants don't have integer type.
- use layout::Primitive;
- let discr_layout = self.layout_of(match discr_layout.value {
- Primitive::Int(int, signed) => int.to_ty(*self.tcx, signed),
- Primitive::Pointer => self.tcx.types.usize,
- Primitive::Float(..) => bug!("there are no float discriminants"),
- })?;
+ let discr_layout = self.layout_of(discr_layout.value.to_int_ty(*self.tcx))?;
let discr_val = ImmTy::from_uint(raw_discr, discr_layout);
// We need to use machine arithmetic.
let niche_start_val = ImmTy::from_uint(niche_start, discr_layout);
diff --git a/src/librustc_mir/interpret/place.rs b/src/librustc_mir/interpret/place.rs
index 636b070..9a3d701 100644
--- a/src/librustc_mir/interpret/place.rs
+++ b/src/librustc_mir/interpret/place.rs
@@ -9,7 +9,7 @@
use rustc::mir::interpret::truncate;
use rustc::ty::{self, Ty};
use rustc::ty::layout::{
- self, Size, Align, LayoutOf, TyLayout, HasDataLayout, VariantIdx, IntegerExt
+ self, Size, Align, LayoutOf, TyLayout, HasDataLayout, VariantIdx, PrimitiveExt
};
use rustc::ty::TypeFoldable;
@@ -1060,14 +1060,7 @@
variant_index.as_usize() < dest.layout.ty.ty_adt_def().unwrap().variants.len(),
);
if variant_index != dataful_variant {
- // FIXME: WTF, some discriminants don't have integer type.
- use layout::Primitive;
- let discr_layout = self.layout_of(match discr_layout.value {
- Primitive::Int(int, signed) => int.to_ty(*self.tcx, signed),
- Primitive::Pointer => self.tcx.types.usize,
- Primitive::Float(..) => bug!("there are no float discriminants"),
- })?;
-
+ let discr_layout = self.layout_of(discr_layout.value.to_int_ty(*self.tcx))?;
// We need to use machine arithmetic.
let variants_start = niche_variants.start().as_u32();
let variants_start_val = ImmTy::from_uint(variants_start, discr_layout);
