Enum rustc_middle::mir::consts::Const
source · pub enum Const<'tcx> {
Ty(Const<'tcx>),
Unevaluated(UnevaluatedConst<'tcx>, Ty<'tcx>),
Val(ConstValue<'tcx>, Ty<'tcx>),
}
Expand description
Constants
Variants§
Ty(Const<'tcx>)
This constant came from the type system.
Any way of turning ty::Const
into ConstValue
should go through valtree_to_const_val
;
this ensures that we consistently produce “clean” values without data in the padding or
anything like that.
Unevaluated(UnevaluatedConst<'tcx>, Ty<'tcx>)
An unevaluated mir constant which is not part of the type system.
Note that Ty(ty::ConstKind::Unevaluated)
and this variant are not identical! Ty
will
always flow through a valtree, so all data not captured in the valtree is lost. This variant
directly uses the evaluated result of the given constant, including e.g. data stored in
padding.
Val(ConstValue<'tcx>, Ty<'tcx>)
This constant cannot go back into the type system, as it represents something the type system cannot handle (e.g. pointers).
Implementations§
source§impl<'tcx> Const<'tcx>
impl<'tcx> Const<'tcx>
pub fn ty(&self) -> Ty<'tcx>
pub fn try_to_scalar(self) -> Option<Scalar>
pub fn try_to_scalar_int(self) -> Option<ScalarInt>
pub fn try_to_bits(self, size: Size) -> Option<u128>
pub fn try_to_bool(self) -> Option<bool>
pub fn eval( self, tcx: TyCtxt<'tcx>, param_env: ParamEnv<'tcx>, span: Option<Span> ) -> Result<ConstValue<'tcx>, ErrorHandled>
sourcepub fn normalize(self, tcx: TyCtxt<'tcx>, param_env: ParamEnv<'tcx>) -> Self
pub fn normalize(self, tcx: TyCtxt<'tcx>, param_env: ParamEnv<'tcx>) -> Self
Normalizes the constant to a value or an error if possible.
pub fn try_eval_scalar( self, tcx: TyCtxt<'tcx>, param_env: ParamEnv<'tcx> ) -> Option<Scalar>
pub fn try_eval_scalar_int( self, tcx: TyCtxt<'tcx>, param_env: ParamEnv<'tcx> ) -> Option<ScalarInt>
pub fn try_eval_bits( &self, tcx: TyCtxt<'tcx>, param_env: ParamEnv<'tcx> ) -> Option<u128>
sourcepub fn eval_bits(self, tcx: TyCtxt<'tcx>, param_env: ParamEnv<'tcx>) -> u128
pub fn eval_bits(self, tcx: TyCtxt<'tcx>, param_env: ParamEnv<'tcx>) -> u128
Panics if the value cannot be evaluated or doesn’t contain a valid integer of the given type.
pub fn try_eval_target_usize( self, tcx: TyCtxt<'tcx>, param_env: ParamEnv<'tcx> ) -> Option<u64>
sourcepub fn eval_target_usize(
self,
tcx: TyCtxt<'tcx>,
param_env: ParamEnv<'tcx>
) -> u64
pub fn eval_target_usize( self, tcx: TyCtxt<'tcx>, param_env: ParamEnv<'tcx> ) -> u64
Panics if the value cannot be evaluated or doesn’t contain a valid usize
.
pub fn try_eval_bool( self, tcx: TyCtxt<'tcx>, param_env: ParamEnv<'tcx> ) -> Option<bool>
pub fn from_value(val: ConstValue<'tcx>, ty: Ty<'tcx>) -> Self
pub fn from_bits( tcx: TyCtxt<'tcx>, bits: u128, param_env_ty: ParamEnvAnd<'tcx, Ty<'tcx>> ) -> Self
pub fn from_bool(tcx: TyCtxt<'tcx>, v: bool) -> Self
pub fn zero_sized(ty: Ty<'tcx>) -> Self
pub fn from_usize(tcx: TyCtxt<'tcx>, n: u64) -> Self
pub fn from_scalar(_tcx: TyCtxt<'tcx>, s: Scalar, ty: Ty<'tcx>) -> Self
sourcepub fn from_anon_const(
tcx: TyCtxt<'tcx>,
def: LocalDefId,
param_env: ParamEnv<'tcx>
) -> Self
pub fn from_anon_const( tcx: TyCtxt<'tcx>, def: LocalDefId, param_env: ParamEnv<'tcx> ) -> Self
Literals are converted to Const::Val
, const generic parameters are eagerly
converted to a constant, everything else becomes Unevaluated
.
pub fn from_ty_const(c: Const<'tcx>, tcx: TyCtxt<'tcx>) -> Self
Trait Implementations§
source§impl<'tcx, '__ctx> HashStable<StableHashingContext<'__ctx>> for Const<'tcx>
impl<'tcx, '__ctx> HashStable<StableHashingContext<'__ctx>> for Const<'tcx>
fn hash_stable( &self, __hcx: &mut StableHashingContext<'__ctx>, __hasher: &mut StableHasher )
source§impl<'tcx> Key for Const<'tcx>
impl<'tcx> Key for Const<'tcx>
type CacheSelector = DefaultCacheSelector<Const<'tcx>>
source§fn default_span(&self, _: TyCtxt<'_>) -> Span
fn default_span(&self, _: TyCtxt<'_>) -> Span
self
, what span should we use?source§fn key_as_def_id(&self) -> Option<DefId>
fn key_as_def_id(&self) -> Option<DefId>
fn ty_adt_id(&self) -> Option<DefId>
source§impl<'tcx> PartialEq<Const<'tcx>> for Const<'tcx>
impl<'tcx> PartialEq<Const<'tcx>> for Const<'tcx>
source§impl<'tcx> TypeFoldable<TyCtxt<'tcx>> for Const<'tcx>
impl<'tcx> TypeFoldable<TyCtxt<'tcx>> for Const<'tcx>
source§fn try_fold_with<__F: FallibleTypeFolder<TyCtxt<'tcx>>>(
self,
__folder: &mut __F
) -> Result<Self, __F::Error>
fn try_fold_with<__F: FallibleTypeFolder<TyCtxt<'tcx>>>( self, __folder: &mut __F ) -> Result<Self, __F::Error>
source§fn fold_with<F>(self, folder: &mut F) -> Selfwhere
F: TypeFolder<I>,
fn fold_with<F>(self, folder: &mut F) -> Selfwhere F: TypeFolder<I>,
try_fold_with
for use with infallible
folders. Do not override this method, to ensure coherence with
try_fold_with
.source§impl<'tcx> TypeVisitable<TyCtxt<'tcx>> for Const<'tcx>
impl<'tcx> TypeVisitable<TyCtxt<'tcx>> for Const<'tcx>
source§fn visit_with<__V: TypeVisitor<TyCtxt<'tcx>>>(
&self,
__visitor: &mut __V
) -> ControlFlow<__V::BreakTy>
fn visit_with<__V: TypeVisitor<TyCtxt<'tcx>>>( &self, __visitor: &mut __V ) -> ControlFlow<__V::BreakTy>
impl<'tcx> Copy for Const<'tcx>
impl<'tcx> Eq for Const<'tcx>
impl<'tcx> StructuralEq for Const<'tcx>
impl<'tcx> StructuralPartialEq for Const<'tcx>
Auto Trait Implementations§
impl<'tcx> !RefUnwindSafe for Const<'tcx>
impl<'tcx> Send for Const<'tcx>
impl<'tcx> Sync for Const<'tcx>
impl<'tcx> Unpin for Const<'tcx>
impl<'tcx> !UnwindSafe for Const<'tcx>
Blanket Implementations§
source§impl<'tcx, T> ArenaAllocatable<'tcx, IsCopy> for Twhere
T: Copy,
impl<'tcx, T> ArenaAllocatable<'tcx, IsCopy> for Twhere T: Copy,
fn allocate_on<'a>(self, arena: &'a Arena<'tcx>) -> &'a mut T
fn allocate_from_iter<'a>( arena: &'a Arena<'tcx>, iter: impl IntoIterator<Item = T> ) -> &'a mut [T]
source§impl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere T: ?Sized,
source§fn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
source§impl<T, R> CollectAndApply<T, R> for T
impl<T, R> CollectAndApply<T, R> for T
source§impl<Tcx, T> DepNodeParams<Tcx> for Twhere
Tcx: DepContext,
T: for<'a> HashStable<StableHashingContext<'a>> + Debug,
impl<Tcx, T> DepNodeParams<Tcx> for Twhere Tcx: DepContext, T: for<'a> HashStable<StableHashingContext<'a>> + Debug,
default fn fingerprint_style() -> FingerprintStyle
source§default fn to_fingerprint(&self, tcx: Tcx) -> Fingerprint
default fn to_fingerprint(&self, tcx: Tcx) -> Fingerprint
default fn to_debug_str(&self, _: Tcx) -> String
source§default fn recover(_: Tcx, _: &DepNode) -> Option<T>
default fn recover(_: Tcx, _: &DepNode) -> Option<T>
DepNode
,
something which is needed when forcing DepNode
s during red-green
evaluation. The query system will only call this method if
fingerprint_style()
is not FingerprintStyle::Opaque
.
It is always valid to return None
here, in which case incremental
compilation will treat the query as having changed instead of forcing it.source§impl<P> IntoQueryParam<P> for P
impl<P> IntoQueryParam<P> for P
fn into_query_param(self) -> P
source§impl<'tcx, T> IsSuggestable<'tcx> for Twhere
T: TypeVisitable<TyCtxt<'tcx>> + TypeFoldable<TyCtxt<'tcx>>,
impl<'tcx, T> IsSuggestable<'tcx> for Twhere T: TypeVisitable<TyCtxt<'tcx>> + TypeFoldable<TyCtxt<'tcx>>,
source§impl<T> MaybeResult<T> for T
impl<T> MaybeResult<T> for T
source§impl<'tcx, T> ToPredicate<'tcx, T> for T
impl<'tcx, T> ToPredicate<'tcx, T> for T
fn to_predicate(self, _tcx: TyCtxt<'tcx>) -> T
source§impl<'tcx, T> TypeVisitableExt<'tcx> for Twhere
T: TypeVisitable<TyCtxt<'tcx>>,
impl<'tcx, T> TypeVisitableExt<'tcx> for Twhere T: TypeVisitable<TyCtxt<'tcx>>,
source§fn has_vars_bound_at_or_above(&self, binder: DebruijnIndex) -> bool
fn has_vars_bound_at_or_above(&self, binder: DebruijnIndex) -> bool
true
if self
has any late-bound regions that are either
bound by binder
or bound by some binder outside of binder
.
If binder
is ty::INNERMOST
, this indicates whether
there are any late-bound regions that appear free.source§fn has_vars_bound_above(&self, binder: DebruijnIndex) -> bool
fn has_vars_bound_above(&self, binder: DebruijnIndex) -> bool
true
if this type has any regions that escape binder
(and
hence are not bound by it).source§fn has_escaping_bound_vars(&self) -> bool
fn has_escaping_bound_vars(&self) -> bool
true
if this type has regions that are not a part of the type.
For example, for<'a> fn(&'a i32)
return false
, while fn(&'a i32)
would return true
. The latter can occur when traversing through the
former. Read morefn has_type_flags(&self, flags: TypeFlags) -> bool
fn has_projections(&self) -> bool
fn has_inherent_projections(&self) -> bool
fn has_opaque_types(&self) -> bool
fn has_generators(&self) -> bool
fn references_error(&self) -> bool
fn error_reported(&self) -> Result<(), ErrorGuaranteed>
fn has_non_region_param(&self) -> bool
fn has_infer_regions(&self) -> bool
fn has_infer_types(&self) -> bool
fn has_non_region_infer(&self) -> bool
fn has_infer(&self) -> bool
fn has_placeholders(&self) -> bool
fn has_non_region_placeholders(&self) -> bool
fn has_param(&self) -> bool
source§fn has_free_regions(&self) -> bool
fn has_free_regions(&self) -> bool
fn has_erased_regions(&self) -> bool
source§fn has_erasable_regions(&self) -> bool
fn has_erasable_regions(&self) -> bool
source§fn is_global(&self) -> bool
fn is_global(&self) -> bool
source§fn has_late_bound_regions(&self) -> bool
fn has_late_bound_regions(&self) -> bool
source§fn has_non_region_late_bound(&self) -> bool
fn has_non_region_late_bound(&self) -> bool
source§fn has_late_bound_vars(&self) -> bool
fn has_late_bound_vars(&self) -> bool
source§fn still_further_specializable(&self) -> bool
fn still_further_specializable(&self) -> bool
impl
specialization.source§impl<Tcx, T> Value<Tcx> for Twhere
Tcx: DepContext,
impl<Tcx, T> Value<Tcx> for Twhere Tcx: DepContext,
default fn from_cycle_error( tcx: Tcx, cycle: &[QueryInfo], _guar: ErrorGuaranteed ) -> T
Layout§
Note: Most layout information is completely unstable and may even differ between compilations. The only exception is types with certain repr(...)
attributes. Please see the Rust Reference's “Type Layout” chapter for details on type layout guarantees.
Size: 40 bytes
Size for each variant:
Ty
: 8 bytesUnevaluated
: 32 bytesVal
: 32 bytes