use rustc_ast::ast::Mutability;
use rustc_data_structures::fx::FxHashMap;
use rustc_hir as hir;
+use rustc_hir::def::{CtorKind, DefKind, Res};
use rustc_hir::def_id::DefId;
-use rustc_hir::{TyKind, Unsafety};
+use rustc_hir::{Expr, TyKind, Unsafety};
use rustc_infer::infer::TyCtxtInferExt;
use rustc_lint::LateContext;
-use rustc_middle::ty::subst::{GenericArg, GenericArgKind};
-use rustc_middle::ty::{self, AdtDef, IntTy, Predicate, Ty, TyCtxt, TypeFoldable, UintTy};
+use rustc_middle::mir::interpret::{ConstValue, Scalar};
+use rustc_middle::ty::subst::{GenericArg, GenericArgKind, Subst};
+use rustc_middle::ty::{
+ self, AdtDef, Binder, FnSig, IntTy, Predicate, PredicateKind, Ty, TyCtxt, TypeFoldable, UintTy, VariantDiscr,
+};
use rustc_span::symbol::Ident;
use rustc_span::{sym, Span, Symbol, DUMMY_SP};
+use rustc_target::abi::{Size, VariantIdx};
use rustc_trait_selection::infer::InferCtxtExt;
use rustc_trait_selection::traits::query::normalize::AtExt;
use std::iter;
-use crate::{match_def_path, must_use_attr};
+use crate::{match_def_path, must_use_attr, path_res};
// Checks if the given type implements copy.
pub fn is_copy<'tcx>(cx: &LateContext<'tcx>, ty: Ty<'tcx>) -> bool {
}
/// Checks whether a type can be partially moved.
-pub fn can_partially_move_ty(cx: &LateContext<'tcx>, ty: Ty<'tcx>) -> bool {
+pub fn can_partially_move_ty<'tcx>(cx: &LateContext<'tcx>, ty: Ty<'tcx>) -> bool {
if has_drop(cx, ty) || is_copy(cx, ty) {
return false;
}
}
/// Walks into `ty` and returns `true` if any inner type is the same as `other_ty`
-pub fn contains_ty<'tcx>(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>, other_ty: Ty<'tcx>) -> bool {
- ty.walk(tcx).any(|inner| match inner.unpack() {
- GenericArgKind::Type(inner_ty) => ty::TyS::same_type(other_ty, inner_ty),
+pub fn contains_ty(ty: Ty<'_>, other_ty: Ty<'_>) -> bool {
+ ty.walk().any(|inner| match inner.unpack() {
+ GenericArgKind::Type(inner_ty) => other_ty == inner_ty,
GenericArgKind::Lifetime(_) | GenericArgKind::Const(_) => false,
})
}
/// Walks into `ty` and returns `true` if any inner type is an instance of the given adt
/// constructor.
-pub fn contains_adt_constructor<'tcx>(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>, adt: &'tcx AdtDef) -> bool {
- ty.walk(tcx).any(|inner| match inner.unpack() {
+pub fn contains_adt_constructor(ty: Ty<'_>, adt: &AdtDef) -> bool {
+ ty.walk().any(|inner| match inner.unpack() {
GenericArgKind::Type(inner_ty) => inner_ty.ty_adt_def() == Some(adt),
GenericArgKind::Lifetime(_) | GenericArgKind::Const(_) => false,
})
.iter()
.all(|field| is_normalizable_helper(cx, param_env, field.ty(cx.tcx, substs), cache))
}),
- _ => ty.walk(cx.tcx).all(|generic_arg| match generic_arg.unpack() {
+ _ => ty.walk().all(|generic_arg| match generic_arg.unpack() {
GenericArgKind::Type(inner_ty) if inner_ty != ty => {
is_normalizable_helper(cx, param_env, inner_ty, cache)
},
/// Returns `true` if types `a` and `b` are same types having same `Const` generic args,
/// otherwise returns `false`
-pub fn same_type_and_consts(a: Ty<'tcx>, b: Ty<'tcx>) -> bool {
+pub fn same_type_and_consts<'tcx>(a: Ty<'tcx>, b: Ty<'tcx>) -> bool {
match (&a.kind(), &b.kind()) {
(&ty::Adt(did_a, substs_a), &ty::Adt(did_b, substs_b)) => {
if did_a != did_b {
})
.flatten()
}
+
+/// A signature for a function like type.
+#[derive(Clone, Copy)]
+pub enum ExprFnSig<'tcx> {
+ Sig(Binder<'tcx, FnSig<'tcx>>),
+ Closure(Binder<'tcx, FnSig<'tcx>>),
+ Trait(Binder<'tcx, Ty<'tcx>>, Option<Binder<'tcx, Ty<'tcx>>>),
+}
+impl<'tcx> ExprFnSig<'tcx> {
+ /// Gets the argument type at the given offset.
+ pub fn input(self, i: usize) -> Binder<'tcx, Ty<'tcx>> {
+ match self {
+ Self::Sig(sig) => sig.input(i),
+ Self::Closure(sig) => sig.input(0).map_bound(|ty| ty.tuple_element_ty(i).unwrap()),
+ Self::Trait(inputs, _) => inputs.map_bound(|ty| ty.tuple_element_ty(i).unwrap()),
+ }
+ }
+
+ /// Gets the result type, if one could be found. Note that the result type of a trait may not be
+ /// specified.
+ pub fn output(self) -> Option<Binder<'tcx, Ty<'tcx>>> {
+ match self {
+ Self::Sig(sig) | Self::Closure(sig) => Some(sig.output()),
+ Self::Trait(_, output) => output,
+ }
+ }
+}
+
+/// If the expression is function like, get the signature for it.
+pub fn expr_sig<'tcx>(cx: &LateContext<'tcx>, expr: &Expr<'_>) -> Option<ExprFnSig<'tcx>> {
+ if let Res::Def(DefKind::Fn | DefKind::Ctor(_, CtorKind::Fn) | DefKind::AssocFn, id) = path_res(cx, expr) {
+ Some(ExprFnSig::Sig(cx.tcx.fn_sig(id)))
+ } else {
+ let ty = cx.typeck_results().expr_ty_adjusted(expr).peel_refs();
+ match *ty.kind() {
+ ty::Closure(_, subs) => Some(ExprFnSig::Closure(subs.as_closure().sig())),
+ ty::FnDef(id, subs) => Some(ExprFnSig::Sig(cx.tcx.fn_sig(id).subst(cx.tcx, subs))),
+ ty::FnPtr(sig) => Some(ExprFnSig::Sig(sig)),
+ ty::Dynamic(bounds, _) => {
+ let lang_items = cx.tcx.lang_items();
+ match bounds.principal() {
+ Some(bound)
+ if Some(bound.def_id()) == lang_items.fn_trait()
+ || Some(bound.def_id()) == lang_items.fn_once_trait()
+ || Some(bound.def_id()) == lang_items.fn_mut_trait() =>
+ {
+ let output = bounds
+ .projection_bounds()
+ .find(|p| lang_items.fn_once_output().map_or(false, |id| id == p.item_def_id()))
+ .map(|p| p.map_bound(|p| p.term.ty().expect("return type was a const")));
+ Some(ExprFnSig::Trait(bound.map_bound(|b| b.substs.type_at(0)), output))
+ },
+ _ => None,
+ }
+ },
+ ty::Param(_) | ty::Projection(..) => {
+ let mut inputs = None;
+ let mut output = None;
+ let lang_items = cx.tcx.lang_items();
+
+ for (pred, _) in all_predicates_of(cx.tcx, cx.typeck_results().hir_owner.to_def_id()) {
+ let mut is_input = false;
+ if let Some(ty) = pred
+ .kind()
+ .map_bound(|pred| match pred {
+ PredicateKind::Trait(p)
+ if (lang_items.fn_trait() == Some(p.def_id())
+ || lang_items.fn_mut_trait() == Some(p.def_id())
+ || lang_items.fn_once_trait() == Some(p.def_id()))
+ && p.self_ty() == ty =>
+ {
+ is_input = true;
+ Some(p.trait_ref.substs.type_at(1))
+ },
+ PredicateKind::Projection(p)
+ if Some(p.projection_ty.item_def_id) == lang_items.fn_once_output()
+ && p.projection_ty.self_ty() == ty =>
+ {
+ is_input = false;
+ p.term.ty()
+ },
+ _ => None,
+ })
+ .transpose()
+ {
+ if is_input && inputs.is_none() {
+ inputs = Some(ty);
+ } else if !is_input && output.is_none() {
+ output = Some(ty);
+ } else {
+ // Multiple different fn trait impls. Is this even allowed?
+ return None;
+ }
+ }
+ }
+
+ inputs.map(|ty| ExprFnSig::Trait(ty, output))
+ },
+ _ => None,
+ }
+ }
+}
+
+#[derive(Clone, Copy)]
+pub enum EnumValue {
+ Unsigned(u128),
+ Signed(i128),
+}
+impl core::ops::Add<u32> for EnumValue {
+ type Output = Self;
+ fn add(self, n: u32) -> Self::Output {
+ match self {
+ Self::Unsigned(x) => Self::Unsigned(x + u128::from(n)),
+ Self::Signed(x) => Self::Signed(x + i128::from(n)),
+ }
+ }
+}
+
+/// Attempts to read the given constant as though it were an an enum value.
+#[allow(clippy::cast_possible_truncation, clippy::cast_possible_wrap)]
+pub fn read_explicit_enum_value(tcx: TyCtxt<'_>, id: DefId) -> Option<EnumValue> {
+ if let Ok(ConstValue::Scalar(Scalar::Int(value))) = tcx.const_eval_poly(id) {
+ match tcx.type_of(id).kind() {
+ ty::Int(_) => Some(EnumValue::Signed(match value.size().bytes() {
+ 1 => i128::from(value.assert_bits(Size::from_bytes(1)) as u8 as i8),
+ 2 => i128::from(value.assert_bits(Size::from_bytes(2)) as u16 as i16),
+ 4 => i128::from(value.assert_bits(Size::from_bytes(4)) as u32 as i32),
+ 8 => i128::from(value.assert_bits(Size::from_bytes(8)) as u64 as i64),
+ 16 => value.assert_bits(Size::from_bytes(16)) as i128,
+ _ => return None,
+ })),
+ ty::Uint(_) => Some(EnumValue::Unsigned(match value.size().bytes() {
+ 1 => value.assert_bits(Size::from_bytes(1)),
+ 2 => value.assert_bits(Size::from_bytes(2)),
+ 4 => value.assert_bits(Size::from_bytes(4)),
+ 8 => value.assert_bits(Size::from_bytes(8)),
+ 16 => value.assert_bits(Size::from_bytes(16)),
+ _ => return None,
+ })),
+ _ => None,
+ }
+ } else {
+ None
+ }
+}
+
+/// Gets the value of the given variant.
+pub fn get_discriminant_value(tcx: TyCtxt<'_>, adt: &'_ AdtDef, i: VariantIdx) -> EnumValue {
+ let variant = &adt.variants[i];
+ match variant.discr {
+ VariantDiscr::Explicit(id) => read_explicit_enum_value(tcx, id).unwrap(),
+ VariantDiscr::Relative(x) => match adt.variants[(i.as_usize() - x as usize).into()].discr {
+ VariantDiscr::Explicit(id) => read_explicit_enum_value(tcx, id).unwrap() + x,
+ VariantDiscr::Relative(_) => EnumValue::Unsigned(x.into()),
+ },
+ }
+}
projects / rust.git / blobdiff