rust/compiler/rustc_query_impl/src/plumbing.rs

559 lines
19 KiB
Rust

//! The implementation of the query system itself. This defines the macros that
//! generate the actual methods on tcx which find and execute the provider,
//! manage the caches, and so forth.
use crate::{on_disk_cache, Queries};
use rustc_middle::dep_graph::{DepNodeIndex, SerializedDepNodeIndex};
use rustc_middle::ty::tls::{self, ImplicitCtxt};
use rustc_middle::ty::TyCtxt;
use rustc_query_system::dep_graph::HasDepContext;
use rustc_query_system::query::{QueryContext, QueryJobId, QueryMap, QuerySideEffects};
use rustc_data_structures::sync::Lock;
use rustc_data_structures::thin_vec::ThinVec;
use rustc_errors::{Diagnostic, Handler};
use std::any::Any;
use std::num::NonZeroU64;
#[derive(Copy, Clone)]
pub struct QueryCtxt<'tcx> {
pub tcx: TyCtxt<'tcx>,
pub queries: &'tcx Queries<'tcx>,
}
impl<'tcx> std::ops::Deref for QueryCtxt<'tcx> {
type Target = TyCtxt<'tcx>;
#[inline]
fn deref(&self) -> &Self::Target {
&self.tcx
}
}
impl<'tcx> HasDepContext for QueryCtxt<'tcx> {
type DepKind = rustc_middle::dep_graph::DepKind;
type DepContext = TyCtxt<'tcx>;
#[inline]
fn dep_context(&self) -> &Self::DepContext {
&self.tcx
}
}
impl QueryContext for QueryCtxt<'_> {
fn next_job_id(&self) -> QueryJobId {
QueryJobId(
NonZeroU64::new(
self.queries.jobs.fetch_add(1, rustc_data_structures::sync::Ordering::Relaxed),
)
.unwrap(),
)
}
fn current_query_job(&self) -> Option<QueryJobId> {
tls::with_related_context(**self, |icx| icx.query)
}
fn try_collect_active_jobs(&self) -> Option<QueryMap> {
self.queries.try_collect_active_jobs(**self)
}
// Interactions with on_disk_cache
fn load_side_effects(&self, prev_dep_node_index: SerializedDepNodeIndex) -> QuerySideEffects {
self.queries
.on_disk_cache
.as_ref()
.map(|c| c.load_side_effects(**self, prev_dep_node_index))
.unwrap_or_default()
}
fn store_side_effects(&self, dep_node_index: DepNodeIndex, side_effects: QuerySideEffects) {
if let Some(c) = self.queries.on_disk_cache.as_ref() {
c.store_side_effects(dep_node_index, side_effects)
}
}
fn store_side_effects_for_anon_node(
&self,
dep_node_index: DepNodeIndex,
side_effects: QuerySideEffects,
) {
if let Some(c) = self.queries.on_disk_cache.as_ref() {
c.store_side_effects_for_anon_node(dep_node_index, side_effects)
}
}
/// Executes a job by changing the `ImplicitCtxt` to point to the
/// new query job while it executes. It returns the diagnostics
/// captured during execution and the actual result.
#[inline(always)]
fn start_query<R>(
&self,
token: QueryJobId,
diagnostics: Option<&Lock<ThinVec<Diagnostic>>>,
compute: impl FnOnce() -> R,
) -> R {
// The `TyCtxt` stored in TLS has the same global interner lifetime
// as `self`, so we use `with_related_context` to relate the 'tcx lifetimes
// when accessing the `ImplicitCtxt`.
tls::with_related_context(**self, move |current_icx| {
// Update the `ImplicitCtxt` to point to our new query job.
let new_icx = ImplicitCtxt {
tcx: **self,
query: Some(token),
diagnostics,
layout_depth: current_icx.layout_depth,
task_deps: current_icx.task_deps,
};
// Use the `ImplicitCtxt` while we execute the query.
tls::enter_context(&new_icx, |_| {
rustc_data_structures::stack::ensure_sufficient_stack(compute)
})
})
}
}
impl<'tcx> QueryCtxt<'tcx> {
#[inline]
pub fn from_tcx(tcx: TyCtxt<'tcx>) -> Self {
let queries = tcx.queries.as_any();
let queries = unsafe {
let queries = std::mem::transmute::<&dyn Any, &dyn Any>(queries);
let queries = queries.downcast_ref().unwrap();
let queries = std::mem::transmute::<&Queries<'_>, &Queries<'_>>(queries);
queries
};
QueryCtxt { tcx, queries }
}
pub(crate) fn on_disk_cache(self) -> Option<&'tcx on_disk_cache::OnDiskCache<'tcx>> {
self.queries.on_disk_cache.as_ref()
}
pub(super) fn encode_query_results(
self,
encoder: &mut on_disk_cache::CacheEncoder<'_, 'tcx>,
query_result_index: &mut on_disk_cache::EncodedDepNodeIndex,
) {
macro_rules! encode_queries {
($($query:ident,)*) => {
$(
on_disk_cache::encode_query_results::<_, super::queries::$query<'_>>(
self,
encoder,
query_result_index
);
)*
}
}
rustc_cached_queries!(encode_queries!);
}
pub fn try_print_query_stack(
self,
query: Option<QueryJobId>,
handler: &Handler,
num_frames: Option<usize>,
) -> usize {
rustc_query_system::query::print_query_stack(self, query, handler, num_frames)
}
}
macro_rules! handle_cycle_error {
([][$tcx: expr, $error:expr]) => {{
$error.emit();
Value::from_cycle_error($tcx)
}};
([(fatal_cycle) $($rest:tt)*][$tcx:expr, $error:expr]) => {{
$error.emit();
$tcx.sess.abort_if_errors();
unreachable!()
}};
([(cycle_delay_bug) $($rest:tt)*][$tcx:expr, $error:expr]) => {{
$error.delay_as_bug();
Value::from_cycle_error($tcx)
}};
([$other:tt $($modifiers:tt)*][$($args:tt)*]) => {
handle_cycle_error!([$($modifiers)*][$($args)*])
};
}
macro_rules! is_anon {
([]) => {{
false
}};
([(anon) $($rest:tt)*]) => {{
true
}};
([$other:tt $($modifiers:tt)*]) => {
is_anon!([$($modifiers)*])
};
}
macro_rules! is_eval_always {
([]) => {{
false
}};
([(eval_always) $($rest:tt)*]) => {{
true
}};
([$other:tt $($modifiers:tt)*]) => {
is_eval_always!([$($modifiers)*])
};
}
macro_rules! hash_result {
([]) => {{
Some(dep_graph::hash_result)
}};
([(no_hash) $($rest:tt)*]) => {{
None
}};
([$other:tt $($modifiers:tt)*]) => {
hash_result!([$($modifiers)*])
};
}
macro_rules! get_provider {
([][$tcx:expr, $name:ident, $key:expr]) => {{
$tcx.queries.local_providers.$name
}};
([(separate_provide_extern) $($rest:tt)*][$tcx:expr, $name:ident, $key:expr]) => {{
if $key.query_crate_is_local() {
$tcx.queries.local_providers.$name
} else {
$tcx.queries.extern_providers.$name
}
}};
([$other:tt $($modifiers:tt)*][$($args:tt)*]) => {
get_provider!([$($modifiers)*][$($args)*])
};
}
macro_rules! opt_remap_env_constness {
([][$name:ident]) => {};
([(remap_env_constness) $($rest:tt)*][$name:ident]) => {
let $name = $name.without_const();
};
([$other:tt $($modifiers:tt)*][$name:ident]) => {
opt_remap_env_constness!([$($modifiers)*][$name])
};
}
macro_rules! define_queries {
(<$tcx:tt>
$($(#[$attr:meta])*
[$($modifiers:tt)*] fn $name:ident($($K:tt)*) -> $V:ty,)*) => {
define_queries_struct! {
tcx: $tcx,
input: ($(([$($modifiers)*] [$($attr)*] [$name]))*)
}
mod make_query {
use super::*;
// Create an eponymous constructor for each query.
$(#[allow(nonstandard_style)] $(#[$attr])*
pub fn $name<$tcx>(tcx: QueryCtxt<$tcx>, key: query_keys::$name<$tcx>) -> QueryStackFrame {
opt_remap_env_constness!([$($modifiers)*][key]);
let kind = dep_graph::DepKind::$name;
let name = stringify!($name);
// Disable visible paths printing for performance reasons.
// Showing visible path instead of any path is not that important in production.
let description = ty::print::with_no_visible_paths!(
// Force filename-line mode to avoid invoking `type_of` query.
ty::print::with_forced_impl_filename_line!(
queries::$name::describe(tcx, key)
)
);
let description = if tcx.sess.verbose() {
format!("{} [{}]", description, name)
} else {
description
};
let span = if kind == dep_graph::DepKind::def_span {
// The `def_span` query is used to calculate `default_span`,
// so exit to avoid infinite recursion.
None
} else {
Some(key.default_span(*tcx))
};
let def_kind = if kind == dep_graph::DepKind::opt_def_kind {
// Try to avoid infinite recursion.
None
} else {
key.key_as_def_id()
.and_then(|def_id| def_id.as_local())
.and_then(|def_id| tcx.opt_def_kind(def_id))
};
let hash = || {
tcx.with_stable_hashing_context(|mut hcx|{
let mut hasher = StableHasher::new();
std::mem::discriminant(&kind).hash_stable(&mut hcx, &mut hasher);
key.hash_stable(&mut hcx, &mut hasher);
hasher.finish::<u64>()
})
};
QueryStackFrame::new(name, description, span, def_kind, hash)
})*
}
#[allow(nonstandard_style)]
mod queries {
use std::marker::PhantomData;
$(pub struct $name<$tcx> {
data: PhantomData<&$tcx ()>
})*
}
$(impl<$tcx> QueryConfig for queries::$name<$tcx> {
type Key = query_keys::$name<$tcx>;
type Value = query_values::$name<$tcx>;
type Stored = query_stored::$name<$tcx>;
const NAME: &'static str = stringify!($name);
}
impl<$tcx> QueryDescription<QueryCtxt<$tcx>> for queries::$name<$tcx> {
rustc_query_description! { $name<$tcx> }
type Cache = query_storage::$name<$tcx>;
#[inline(always)]
fn query_state<'a>(tcx: QueryCtxt<$tcx>) -> &'a QueryState<Self::Key>
where QueryCtxt<$tcx>: 'a
{
&tcx.queries.$name
}
#[inline(always)]
fn query_cache<'a>(tcx: QueryCtxt<$tcx>) -> &'a Self::Cache
where 'tcx:'a
{
&tcx.query_caches.$name
}
#[inline]
fn make_vtable(tcx: QueryCtxt<'tcx>, key: &Self::Key) ->
QueryVTable<QueryCtxt<$tcx>, Self::Key, Self::Value>
{
let compute = get_provider!([$($modifiers)*][tcx, $name, key]);
let cache_on_disk = Self::cache_on_disk(tcx.tcx, key);
QueryVTable {
anon: is_anon!([$($modifiers)*]),
eval_always: is_eval_always!([$($modifiers)*]),
dep_kind: dep_graph::DepKind::$name,
hash_result: hash_result!([$($modifiers)*]),
handle_cycle_error: |tcx, mut error| handle_cycle_error!([$($modifiers)*][tcx, error]),
compute,
cache_on_disk,
try_load_from_disk: Self::TRY_LOAD_FROM_DISK,
}
}
})*
#[allow(nonstandard_style)]
mod query_callbacks {
use super::*;
use rustc_middle::dep_graph::DepNode;
use rustc_middle::ty::query::query_keys;
use rustc_query_system::dep_graph::DepNodeParams;
use rustc_query_system::query::{force_query, QueryDescription};
use rustc_query_system::dep_graph::FingerprintStyle;
// We use this for most things when incr. comp. is turned off.
pub fn Null() -> DepKindStruct {
DepKindStruct {
is_anon: false,
is_eval_always: false,
fingerprint_style: FingerprintStyle::Unit,
force_from_dep_node: Some(|_, dep_node| bug!("force_from_dep_node: encountered {:?}", dep_node)),
try_load_from_on_disk_cache: None,
}
}
// We use this for the forever-red node.
pub fn Red() -> DepKindStruct {
DepKindStruct {
is_anon: false,
is_eval_always: false,
fingerprint_style: FingerprintStyle::Unit,
force_from_dep_node: Some(|_, dep_node| bug!("force_from_dep_node: encountered {:?}", dep_node)),
try_load_from_on_disk_cache: None,
}
}
pub fn TraitSelect() -> DepKindStruct {
DepKindStruct {
is_anon: true,
is_eval_always: false,
fingerprint_style: FingerprintStyle::Unit,
force_from_dep_node: None,
try_load_from_on_disk_cache: None,
}
}
pub fn CompileCodegenUnit() -> DepKindStruct {
DepKindStruct {
is_anon: false,
is_eval_always: false,
fingerprint_style: FingerprintStyle::Opaque,
force_from_dep_node: None,
try_load_from_on_disk_cache: None,
}
}
pub fn CompileMonoItem() -> DepKindStruct {
DepKindStruct {
is_anon: false,
is_eval_always: false,
fingerprint_style: FingerprintStyle::Opaque,
force_from_dep_node: None,
try_load_from_on_disk_cache: None,
}
}
$(pub(crate) fn $name()-> DepKindStruct {
let is_anon = is_anon!([$($modifiers)*]);
let is_eval_always = is_eval_always!([$($modifiers)*]);
let fingerprint_style =
<query_keys::$name<'_> as DepNodeParams<TyCtxt<'_>>>::fingerprint_style();
if is_anon || !fingerprint_style.reconstructible() {
return DepKindStruct {
is_anon,
is_eval_always,
fingerprint_style,
force_from_dep_node: None,
try_load_from_on_disk_cache: None,
}
}
#[inline(always)]
fn recover<'tcx>(tcx: TyCtxt<'tcx>, dep_node: DepNode) -> Option<query_keys::$name<'tcx>> {
<query_keys::$name<'_> as DepNodeParams<TyCtxt<'_>>>::recover(tcx, &dep_node)
}
fn force_from_dep_node(tcx: TyCtxt<'_>, dep_node: DepNode) -> bool {
if let Some(key) = recover(tcx, dep_node) {
#[cfg(debug_assertions)]
let _guard = tracing::span!(tracing::Level::TRACE, stringify!($name), ?key).entered();
let tcx = QueryCtxt::from_tcx(tcx);
force_query::<queries::$name<'_>, _>(tcx, key, dep_node);
true
} else {
false
}
}
fn try_load_from_on_disk_cache(tcx: TyCtxt<'_>, dep_node: DepNode) {
debug_assert!(tcx.dep_graph.is_green(&dep_node));
let key = recover(tcx, dep_node).unwrap_or_else(|| panic!("Failed to recover key for {:?} with hash {}", dep_node, dep_node.hash));
if queries::$name::cache_on_disk(tcx, &key) {
let _ = tcx.$name(key);
}
}
DepKindStruct {
is_anon,
is_eval_always,
fingerprint_style,
force_from_dep_node: Some(force_from_dep_node),
try_load_from_on_disk_cache: Some(try_load_from_on_disk_cache),
}
})*
}
pub fn query_callbacks<'tcx>(arena: &'tcx Arena<'tcx>) -> &'tcx [DepKindStruct] {
arena.alloc_from_iter(make_dep_kind_array!(query_callbacks))
}
}
}
// FIXME(eddyb) this macro (and others?) use `$tcx` and `'tcx` interchangeably.
// We should either not take `$tcx` at all and use `'tcx` everywhere, or use
// `$tcx` everywhere (even if that isn't necessary due to lack of hygiene).
macro_rules! define_queries_struct {
(tcx: $tcx:tt,
input: ($(([$($modifiers:tt)*] [$($attr:tt)*] [$name:ident]))*)) => {
pub struct Queries<$tcx> {
local_providers: Box<Providers>,
extern_providers: Box<ExternProviders>,
pub on_disk_cache: Option<OnDiskCache<$tcx>>,
jobs: AtomicU64,
$($(#[$attr])* $name: QueryState<query_keys::$name<$tcx>>,)*
}
impl<$tcx> Queries<$tcx> {
pub fn new(
local_providers: Providers,
extern_providers: ExternProviders,
on_disk_cache: Option<OnDiskCache<$tcx>>,
) -> Self {
Queries {
local_providers: Box::new(local_providers),
extern_providers: Box::new(extern_providers),
on_disk_cache,
jobs: AtomicU64::new(1),
$($name: Default::default()),*
}
}
pub(crate) fn try_collect_active_jobs(
&$tcx self,
tcx: TyCtxt<$tcx>,
) -> Option<QueryMap> {
let tcx = QueryCtxt { tcx, queries: self };
let mut jobs = QueryMap::default();
$(
self.$name.try_collect_active_jobs(
tcx,
make_query::$name,
&mut jobs,
)?;
)*
Some(jobs)
}
}
impl<'tcx> QueryEngine<'tcx> for Queries<'tcx> {
fn as_any(&'tcx self) -> &'tcx dyn std::any::Any {
let this = unsafe { std::mem::transmute::<&Queries<'_>, &Queries<'_>>(self) };
this as _
}
fn try_mark_green(&'tcx self, tcx: TyCtxt<'tcx>, dep_node: &dep_graph::DepNode) -> bool {
let qcx = QueryCtxt { tcx, queries: self };
tcx.dep_graph.try_mark_green(qcx, dep_node).is_some()
}
$($(#[$attr])*
#[inline(always)]
#[tracing::instrument(level = "trace", skip(self, tcx))]
fn $name(
&'tcx self,
tcx: TyCtxt<$tcx>,
span: Span,
key: query_keys::$name<$tcx>,
mode: QueryMode,
) -> Option<query_stored::$name<$tcx>> {
opt_remap_env_constness!([$($modifiers)*][key]);
let qcx = QueryCtxt { tcx, queries: self };
get_query::<queries::$name<$tcx>, _>(qcx, span, key, mode)
})*
}
};
}