Move LitToConstInput into ty::consts

Relocate LitToConstInput and const_lit_matches_ty from mir::interpret
to ty::consts::lit

compiler/rustc_middle/src/mir/interpret/mod.rs

@@ -13,7 +13,7 @@ use std::num::NonZero;
 use std::{fmt, io};
 
 use rustc_abi::{AddressSpace, Align, Endian, HasDataLayout, Size};
-use rustc_ast::{LitKind, Mutability};
+use rustc_ast::Mutability;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::sharded::ShardedHashMap;
 use rustc_data_structures::sync::{AtomicU64, Lock};
@@ -73,55 +73,6 @@ impl<'tcx> GlobalId<'tcx> {
     }
 }
 
-/// Input argument for `tcx.lit_to_const`.
-#[derive(Copy, Clone, Debug, Eq, PartialEq, Hash, HashStable)]
-pub struct LitToConstInput<'tcx> {
-    /// The absolute value of the resultant constant.
-    pub lit: LitKind,
-    /// The type of the constant.
-    pub ty: Ty<'tcx>,
-    /// If the constant is negative.
-    pub neg: bool,
-}
-
-pub fn const_lit_matches_ty<'tcx>(
-    tcx: TyCtxt<'tcx>,
-    kind: &LitKind,
-    ty: Ty<'tcx>,
-    neg: bool,
-) -> bool {
-    match (*kind, ty.kind()) {
-        (LitKind::Str(..), ty::Ref(_, inner_ty, _)) if inner_ty.is_str() => true,
-        (LitKind::Str(..), ty::Str) if tcx.features().deref_patterns() => true,
-        (LitKind::ByteStr(..), ty::Ref(_, inner_ty, _))
-            if let ty::Slice(ty) | ty::Array(ty, _) = inner_ty.kind()
-                && matches!(ty.kind(), ty::Uint(ty::UintTy::U8)) =>
-        {
-            true
-        }
-        (LitKind::ByteStr(..), ty::Slice(inner_ty) | ty::Array(inner_ty, _))
-            if tcx.features().deref_patterns()
-                && matches!(inner_ty.kind(), ty::Uint(ty::UintTy::U8)) =>
-        {
-            true
-        }
-        (LitKind::Byte(..), ty::Uint(ty::UintTy::U8)) => true,
-        (LitKind::CStr(..), ty::Ref(_, inner_ty, _))
-            if matches!(inner_ty.kind(), ty::Adt(def, _)
-                if tcx.is_lang_item(def.did(), rustc_hir::LangItem::CStr)) =>
-        {
-            true
-        }
-        (LitKind::Int(..), ty::Uint(_)) if !neg => true,
-        (LitKind::Int(..), ty::Int(_)) => true,
-        (LitKind::Bool(..), ty::Bool) => true,
-        (LitKind::Float(..), ty::Float(_)) => true,
-        (LitKind::Char(..), ty::Char) => true,
-        (LitKind::Err(..), _) => true,
-        _ => false,
-    }
-}
-
 #[derive(Copy, Clone, Eq, Hash, Ord, PartialEq, PartialOrd)]
 pub struct AllocId(pub NonZero<u64>);
 

compiler/rustc_middle/src/queries.rs

@@ -112,7 +112,7 @@ use crate::middle::resolve_bound_vars::{ObjectLifetimeDefault, ResolveBoundVars,
 use crate::middle::stability::DeprecationEntry;
 use crate::mir::interpret::{
     EvalStaticInitializerRawResult, EvalToAllocationRawResult, EvalToConstValueResult,
-    EvalToValTreeResult, GlobalId, LitToConstInput,
+    EvalToValTreeResult, GlobalId,
 };
 use crate::mir::mono::{
     CodegenUnit, CollectionMode, MonoItem, MonoItemPartitions, NormalizationErrorInMono,
@@ -135,8 +135,8 @@ use crate::ty::layout::ValidityRequirement;
 use crate::ty::print::PrintTraitRefExt;
 use crate::ty::util::AlwaysRequiresDrop;
 use crate::ty::{
-    self, CrateInherentImpls, GenericArg, GenericArgsRef, PseudoCanonicalInput, SizedTraitKind, Ty,
-    TyCtxt, TyCtxtFeed,
+    self, CrateInherentImpls, GenericArg, GenericArgsRef, LitToConstInput, PseudoCanonicalInput,
+    SizedTraitKind, Ty, TyCtxt, TyCtxtFeed,
 };
 use crate::{dep_graph, mir, thir};
 

compiler/rustc_middle/src/query/erase.rs

@@ -445,7 +445,6 @@ impl_erasable_for_single_lifetime_types! {
     rustc_middle::mir::DestructuredConstant,
     rustc_middle::mir::ConstAlloc,
     rustc_middle::mir::interpret::GlobalId,
-    rustc_middle::mir::interpret::LitToConstInput,
     rustc_middle::mir::interpret::EvalStaticInitializerRawResult,
     rustc_middle::mir::mono::MonoItemPartitions,
     rustc_middle::traits::query::MethodAutoderefStepsResult,
@@ -470,6 +469,7 @@ impl_erasable_for_single_lifetime_types! {
     rustc_middle::ty::InstanceKind,
     rustc_middle::ty::layout::FnAbiError,
     rustc_middle::ty::layout::LayoutError,
+    rustc_middle::ty::LitToConstInput,
     rustc_middle::ty::ParamEnv,
     rustc_middle::ty::TypingEnv,
     rustc_middle::ty::Predicate,

compiler/rustc_middle/src/query/keys.rs

@@ -87,7 +87,7 @@ impl<'tcx> Key for (Ty<'tcx>, Option<ty::ExistentialTraitRef<'tcx>>) {
     }
 }
 
-impl<'tcx> Key for mir::interpret::LitToConstInput<'tcx> {
+impl<'tcx> Key for ty::LitToConstInput<'tcx> {
     fn default_span(&self, _tcx: TyCtxt<'_>) -> Span {
         DUMMY_SP
     }

compiler/rustc_middle/src/ty/consts.rs

@@ -11,10 +11,12 @@ use crate::ty::{self, Ty, TyCtxt};
 
 mod int;
 mod kind;
+mod lit;
 mod valtree;
 
 pub use int::*;
 pub use kind::*;
+pub use lit::*;
 use rustc_span::{DUMMY_SP, ErrorGuaranteed};
 pub use valtree::*;
 

compiler/rustc_middle/src/ty/consts/lit.rs

@@ -0,0 +1,55 @@
+use rustc_ast::LitKind;
+use rustc_hir;
+use rustc_macros::HashStable;
+
+use crate::ty::{self, Ty, TyCtxt};
+
+/// Input argument for `tcx.lit_to_const`.
+#[derive(Copy, Clone, Debug, Eq, PartialEq, Hash, HashStable)]
+pub struct LitToConstInput<'tcx> {
+    /// The absolute value of the resultant constant.
+    pub lit: LitKind,
+    /// The type of the constant.
+    pub ty: Ty<'tcx>,
+    /// If the constant is negative.
+    pub neg: bool,
+}
+
+/// Checks whether a literal can be interpreted as a const of the given type.
+pub fn const_lit_matches_ty<'tcx>(
+    tcx: TyCtxt<'tcx>,
+    kind: &LitKind,
+    ty: Ty<'tcx>,
+    neg: bool,
+) -> bool {
+    match (*kind, ty.kind()) {
+        (LitKind::Str(..), ty::Ref(_, inner_ty, _)) if inner_ty.is_str() => true,
+        (LitKind::Str(..), ty::Str) if tcx.features().deref_patterns() => true,
+        (LitKind::ByteStr(..), ty::Ref(_, inner_ty, _))
+            if let ty::Slice(ty) | ty::Array(ty, _) = inner_ty.kind()
+                && matches!(ty.kind(), ty::Uint(ty::UintTy::U8)) =>
+        {
+            true
+        }
+        (LitKind::ByteStr(..), ty::Slice(inner_ty) | ty::Array(inner_ty, _))
+            if tcx.features().deref_patterns()
+                && matches!(inner_ty.kind(), ty::Uint(ty::UintTy::U8)) =>
+        {
+            true
+        }
+        (LitKind::Byte(..), ty::Uint(ty::UintTy::U8)) => true,
+        (LitKind::CStr(..), ty::Ref(_, inner_ty, _))
+            if matches!(inner_ty.kind(), ty::Adt(def, _)
+                if tcx.is_lang_item(def.did(), rustc_hir::LangItem::CStr)) =>
+        {
+            true
+        }
+        (LitKind::Int(..), ty::Uint(_)) if !neg => true,
+        (LitKind::Int(..), ty::Int(_)) => true,
+        (LitKind::Bool(..), ty::Bool) => true,
+        (LitKind::Float(..), ty::Float(_)) => true,
+        (LitKind::Char(..), ty::Char) => true,
+        (LitKind::Err(..), _) => true,
+        _ => false,
+    }
+}

compiler/rustc_middle/src/ty/mod.rs

@@ -76,8 +76,9 @@ pub use self::closure::{
     place_to_string_for_capture,
 };
 pub use self::consts::{
-    AtomicOrdering, Const, ConstInt, ConstKind, ConstToValTreeResult, Expr, ExprKind, ScalarInt,
-    SimdAlign, UnevaluatedConst, ValTree, ValTreeKindExt, Value,
+    AtomicOrdering, Const, ConstInt, ConstKind, ConstToValTreeResult, Expr, ExprKind,
+    LitToConstInput, ScalarInt, SimdAlign, UnevaluatedConst, ValTree, ValTreeKindExt, Value,
+    const_lit_matches_ty,
 };
 pub use self::context::{
     CtxtInterners, CurrentGcx, Feed, FreeRegionInfo, GlobalCtxt, Lift, TyCtxt, TyCtxtFeed, tls,