Struct QueryVTable 

pub struct QueryVTable<'tcx, C: QueryCache> {

    pub name: &'static str,
    pub anon: bool,
    pub eval_always: bool,
    pub depth_limit: bool,
    pub feedable: bool,
    pub dep_kind: DepKind,
    pub cycle_error_handling: CycleErrorHandling,
    pub state: QueryState<'tcx, C::Key>,
    pub cache: C,
    pub will_cache_on_disk_for_key_fn: Option<WillCacheOnDiskForKeyFn<'tcx, C::Key>>,
    pub call_query_method_fn: fn(tcx: TyCtxt<'tcx>, key: C::Key),
    pub invoke_provider_fn: fn(tcx: TyCtxt<'tcx>, key: C::Key) -> C::Value,
    pub try_load_from_disk_fn: Option<TryLoadFromDiskFn<'tcx, C::Key, C::Value>>,
    pub is_loadable_from_disk_fn: Option<IsLoadableFromDiskFn<'tcx, C::Key>>,
    pub hash_result: HashResult<C::Value>,
    pub value_from_cycle_error: fn(tcx: TyCtxt<'tcx>, cycle_error: &CycleError, guar: ErrorGuaranteed) -> C::Value,
    pub format_value: fn(&C::Value) -> String,
    pub description_fn: fn(TyCtxt<'tcx>, C::Key) -> String,
    pub execute_query_fn: fn(TyCtxt<'tcx>, Span, C::Key, QueryMode) -> Option<C::Value>,
}

Stores data and metadata (e.g. function pointers) for a particular query.

Fields

name: &'static str

anon: bool

True if this query has the anon modifier.

eval_always: bool

True if this query has the eval_always modifier.

depth_limit: bool

True if this query has the depth_limit modifier.

feedable: bool

True if this query has the feedable modifier.

dep_kind: DepKind

cycle_error_handling: CycleErrorHandling

How this query deals with query cycle errors.

state: QueryState<'tcx, C::Key>

cache: C

will_cache_on_disk_for_key_fn: Option<WillCacheOnDiskForKeyFn<'tcx, C::Key>>

call_query_method_fn: fn(tcx: TyCtxt<'tcx>, key: C::Key)

Function pointer that calls tcx.$query(key) for this query and discards the returned value.

This is a weird thing to be doing, and probably not what you want. It is used for loading query results from disk-cache in some cases.

invoke_provider_fn: fn(tcx: TyCtxt<'tcx>, key: C::Key) -> C::Value

Function pointer that actually calls this query’s provider. Also performs some associated secondary tasks; see the macro-defined implementation in mod invoke_provider_fn for more details.

This should be the only code that calls the provider function.

try_load_from_disk_fn: Option<TryLoadFromDiskFn<'tcx, C::Key, C::Value>>

is_loadable_from_disk_fn: Option<IsLoadableFromDiskFn<'tcx, C::Key>>

hash_result: HashResult<C::Value>

value_from_cycle_error: fn(tcx: TyCtxt<'tcx>, cycle_error: &CycleError, guar: ErrorGuaranteed) -> C::Value

format_value: fn(&C::Value) -> String

description_fn: fn(TyCtxt<'tcx>, C::Key) -> String

Formats a human-readable description of this query and its key, as specified by the desc query modifier.

Used when reporting query cycle errors and similar problems.

execute_query_fn: fn(TyCtxt<'tcx>, Span, C::Key, QueryMode) -> Option<C::Value>

Function pointer that is called by the query methods on TyCtxt and friends¹, after they have checked the in-memory cache and found no existing value for this key.

Transitive responsibilities include trying to load a disk-cached value if possible (incremental only), invoking the query provider if necessary, and putting the obtained value into the in-memory cache.

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1. TyCtxt, TyCtxtAt, TyCtxtEnsureOk, TyCtxtEnsureDone ↩

Implementations

impl<'tcx, C: QueryCache> QueryVTable<'tcx, C>

pub fn will_cache_on_disk_for_key( &self, tcx: TyCtxt<'tcx>, key: &C::Key, ) -> bool

pub fn try_load_from_disk( &self, tcx: TyCtxt<'tcx>, key: &C::Key, prev_index: SerializedDepNodeIndex, index: DepNodeIndex, ) -> Option<C::Value>

pub fn is_loadable_from_disk( &self, tcx: TyCtxt<'tcx>, key: &C::Key, index: SerializedDepNodeIndex, ) -> bool

pub fn value_from_cycle_error( &self, tcx: TyCtxt<'tcx>, cycle_error: &CycleError, guar: ErrorGuaranteed, ) -> C::Value

Synthesize an error value to let compilation continue after a cycle.

pub fn construct_dep_node(&self, tcx: TyCtxt<'tcx>, key: &C::Key) -> DepNode

Trait Implementations

impl<'tcx, C: QueryCache> Debug for QueryVTable<'tcx, C>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

Layout

Note: Unable to compute type layout, possibly due to this type having generic parameters. Layout can only be computed for concrete, fully-instantiated types.