2 * Methods for the various MIR types. These are intended for use after
3 * building is complete.
7 use crate::ty::layout::VariantIdx;
8 use crate::ty::subst::Subst;
9 use crate::ty::util::IntTypeExt;
10 use crate::ty::{self, Ty, TyCtxt};
13 #[derive(Copy, Clone, Debug, TypeFoldable)]
14 pub struct PlaceTy<'tcx> {
16 /// Downcast to a particular variant of an enum, if included.
17 pub variant_index: Option<VariantIdx>,
20 // At least on 64 bit systems, `PlaceTy` should not be larger than two or three pointers.
21 #[cfg(target_arch = "x86_64")]
22 static_assert_size!(PlaceTy<'_>, 16);
24 impl<'tcx> PlaceTy<'tcx> {
25 pub fn from_ty(ty: Ty<'tcx>) -> PlaceTy<'tcx> {
26 PlaceTy { ty, variant_index: None }
29 /// `place_ty.field_ty(tcx, f)` computes the type at a given field
30 /// of a record or enum-variant. (Most clients of `PlaceTy` can
31 /// instead just extract the relevant type directly from their
32 /// `PlaceElem`, but some instances of `ProjectionElem<V, T>` do
33 /// not carry a `Ty` for `T`.)
35 /// Note that the resulting type has not been normalized.
36 pub fn field_ty(self, tcx: TyCtxt<'tcx>, f: &Field) -> Ty<'tcx> {
37 let answer = match self.ty.kind {
38 ty::Adt(adt_def, substs) => {
39 let variant_def = match self.variant_index {
40 None => adt_def.non_enum_variant(),
41 Some(variant_index) => {
42 assert!(adt_def.is_enum());
43 &adt_def.variants[variant_index]
46 let field_def = &variant_def.fields[f.index()];
47 field_def.ty(tcx, substs)
49 ty::Tuple(ref tys) => tys[f.index()].expect_ty(),
50 _ => bug!("extracting field of non-tuple non-adt: {:?}", self),
52 debug!("field_ty self: {:?} f: {:?} yields: {:?}", self, f, answer);
56 /// Convenience wrapper around `projection_ty_core` for
57 /// `PlaceElem`, where we can just use the `Ty` that is already
58 /// stored inline on field projection elems.
59 pub fn projection_ty(self, tcx: TyCtxt<'tcx>, elem: &PlaceElem<'tcx>) -> PlaceTy<'tcx> {
60 self.projection_ty_core(tcx, ty::ParamEnv::empty(), elem, |_, _, ty| ty)
63 /// `place_ty.projection_ty_core(tcx, elem, |...| { ... })`
64 /// projects `place_ty` onto `elem`, returning the appropriate
65 /// `Ty` or downcast variant corresponding to that projection.
66 /// The `handle_field` callback must map a `Field` to its `Ty`,
67 /// (which should be trivial when `T` = `Ty`).
68 pub fn projection_ty_core<V, T>(
71 param_env: ty::ParamEnv<'tcx>,
72 elem: &ProjectionElem<V, T>,
73 mut handle_field: impl FnMut(&Self, &Field, &T) -> Ty<'tcx>,
79 let answer = match *elem {
80 ProjectionElem::Deref => {
85 bug!("deref projection of non-dereferenceable ty {:?}", self)
90 ProjectionElem::Index(_) | ProjectionElem::ConstantIndex { .. } => {
91 PlaceTy::from_ty(self.ty.builtin_index().unwrap())
93 ProjectionElem::Subslice { from, to, from_end } => {
94 PlaceTy::from_ty(match self.ty.kind {
95 ty::Slice(..) => self.ty,
96 ty::Array(inner, _) if !from_end => tcx.mk_array(inner, (to - from) as u64),
97 ty::Array(inner, size) if from_end => {
98 let size = size.eval_usize(tcx, param_env);
99 let len = size - (from as u64) - (to as u64);
100 tcx.mk_array(inner, len)
102 _ => bug!("cannot subslice non-array type: `{:?}`", self),
105 ProjectionElem::Downcast(_name, index) => {
106 PlaceTy { ty: self.ty, variant_index: Some(index) }
108 ProjectionElem::Field(ref f, ref fty) => PlaceTy::from_ty(handle_field(&self, f, fty)),
110 debug!("projection_ty self: {:?} elem: {:?} yields: {:?}", self, elem, answer);
115 impl<'tcx> Place<'tcx> {
118 projection: &[PlaceElem<'tcx>],
123 D: HasLocalDecls<'tcx>,
127 .fold(PlaceTy::from_ty(local_decls.local_decls()[*local].ty), |place_ty, elem| {
128 place_ty.projection_ty(tcx, elem)
132 pub fn ty<D>(&self, local_decls: &D, tcx: TyCtxt<'tcx>) -> PlaceTy<'tcx>
134 D: HasLocalDecls<'tcx>,
136 Place::ty_from(&self.local, &self.projection, local_decls, tcx)
140 pub enum RvalueInitializationState {
145 impl<'tcx> Rvalue<'tcx> {
146 pub fn ty<D>(&self, local_decls: &D, tcx: TyCtxt<'tcx>) -> Ty<'tcx>
148 D: HasLocalDecls<'tcx>,
151 Rvalue::Use(ref operand) => operand.ty(local_decls, tcx),
152 Rvalue::Repeat(ref operand, count) => tcx.mk_array(operand.ty(local_decls, tcx), count),
153 Rvalue::Ref(reg, bk, ref place) => {
154 let place_ty = place.ty(local_decls, tcx).ty;
155 tcx.mk_ref(reg, ty::TypeAndMut { ty: place_ty, mutbl: bk.to_mutbl_lossy() })
157 Rvalue::AddressOf(mutability, ref place) => {
158 let place_ty = place.ty(local_decls, tcx).ty;
159 tcx.mk_ptr(ty::TypeAndMut { ty: place_ty, mutbl: mutability.into() })
161 Rvalue::Len(..) => tcx.types.usize,
162 Rvalue::Cast(.., ty) => ty,
163 Rvalue::BinaryOp(op, ref lhs, ref rhs) => {
164 let lhs_ty = lhs.ty(local_decls, tcx);
165 let rhs_ty = rhs.ty(local_decls, tcx);
166 op.ty(tcx, lhs_ty, rhs_ty)
168 Rvalue::CheckedBinaryOp(op, ref lhs, ref rhs) => {
169 let lhs_ty = lhs.ty(local_decls, tcx);
170 let rhs_ty = rhs.ty(local_decls, tcx);
171 let ty = op.ty(tcx, lhs_ty, rhs_ty);
172 tcx.intern_tup(&[ty, tcx.types.bool])
174 Rvalue::UnaryOp(UnOp::Not, ref operand) | Rvalue::UnaryOp(UnOp::Neg, ref operand) => {
175 operand.ty(local_decls, tcx)
177 Rvalue::Discriminant(ref place) => {
178 let ty = place.ty(local_decls, tcx).ty;
180 ty::Adt(adt_def, _) => adt_def.repr.discr_type().to_ty(tcx),
181 ty::Generator(_, substs, _) => substs.as_generator().discr_ty(tcx),
183 // This can only be `0`, for now, so `u8` will suffice.
188 Rvalue::NullaryOp(NullOp::Box, t) => tcx.mk_box(t),
189 Rvalue::NullaryOp(NullOp::SizeOf, _) => tcx.types.usize,
190 Rvalue::Aggregate(ref ak, ref ops) => match **ak {
191 AggregateKind::Array(ty) => tcx.mk_array(ty, ops.len() as u64),
192 AggregateKind::Tuple => tcx.mk_tup(ops.iter().map(|op| op.ty(local_decls, tcx))),
193 AggregateKind::Adt(def, _, substs, _, _) => tcx.type_of(def.did).subst(tcx, substs),
194 AggregateKind::Closure(did, substs) => tcx.mk_closure(did, substs),
195 AggregateKind::Generator(did, substs, movability) => {
196 tcx.mk_generator(did, substs, movability)
203 /// Returns `true` if this rvalue is deeply initialized (most rvalues) or
204 /// whether its only shallowly initialized (`Rvalue::Box`).
205 pub fn initialization_state(&self) -> RvalueInitializationState {
207 Rvalue::NullaryOp(NullOp::Box, _) => RvalueInitializationState::Shallow,
208 _ => RvalueInitializationState::Deep,
213 impl<'tcx> Operand<'tcx> {
214 pub fn ty<D>(&self, local_decls: &D, tcx: TyCtxt<'tcx>) -> Ty<'tcx>
216 D: HasLocalDecls<'tcx>,
219 &Operand::Copy(ref l) | &Operand::Move(ref l) => l.ty(local_decls, tcx).ty,
220 &Operand::Constant(ref c) => c.literal.ty,
226 pub fn ty(&self, tcx: TyCtxt<'tcx>, lhs_ty: Ty<'tcx>, rhs_ty: Ty<'tcx>) -> Ty<'tcx> {
227 // FIXME: handle SIMD correctly
237 // these should be integers or floats of the same size.
238 assert_eq!(lhs_ty, rhs_ty);
241 &BinOp::Shl | &BinOp::Shr | &BinOp::Offset => {
242 lhs_ty // lhs_ty can be != rhs_ty
244 &BinOp::Eq | &BinOp::Lt | &BinOp::Le | &BinOp::Ne | &BinOp::Ge | &BinOp::Gt => {
252 pub fn to_mutbl_lossy(self) -> hir::Mutability {
254 BorrowKind::Mut { .. } => hir::Mutability::Mut,
255 BorrowKind::Shared => hir::Mutability::Not,
257 // We have no type corresponding to a unique imm borrow, so
258 // use `&mut`. It gives all the capabilities of an `&uniq`
259 // and hence is a safe "over approximation".
260 BorrowKind::Unique => hir::Mutability::Mut,
262 // We have no type corresponding to a shallow borrow, so use
263 // `&` as an approximation.
264 BorrowKind::Shallow => hir::Mutability::Not,
270 pub fn to_hir_binop(self) -> hir::BinOpKind {
272 BinOp::Add => hir::BinOpKind::Add,
273 BinOp::Sub => hir::BinOpKind::Sub,
274 BinOp::Mul => hir::BinOpKind::Mul,
275 BinOp::Div => hir::BinOpKind::Div,
276 BinOp::Rem => hir::BinOpKind::Rem,
277 BinOp::BitXor => hir::BinOpKind::BitXor,
278 BinOp::BitAnd => hir::BinOpKind::BitAnd,
279 BinOp::BitOr => hir::BinOpKind::BitOr,
280 BinOp::Shl => hir::BinOpKind::Shl,
281 BinOp::Shr => hir::BinOpKind::Shr,
282 BinOp::Eq => hir::BinOpKind::Eq,
283 BinOp::Ne => hir::BinOpKind::Ne,
284 BinOp::Lt => hir::BinOpKind::Lt,
285 BinOp::Gt => hir::BinOpKind::Gt,
286 BinOp::Le => hir::BinOpKind::Le,
287 BinOp::Ge => hir::BinOpKind::Ge,
288 BinOp::Offset => unreachable!(),