resolve: Avoid some unstable iteration

Author: petrochenkov

compiler/rustc_data_structures/src/unord.rs

@@ -259,6 +259,12 @@ impl<V: Eq + Hash> UnordSet<V> {
 self.inner.is_empty()
 }
 
+/// If the set has only one element, returns it, otherwise returns `None`.
+#[inline]
+pubfnget_only(&self) -> Option<&V>{
+ifself.inner.len() == 1{self.inner.iter().next()}else{None}
+}
+
 #[inline]
 pubfninsert(&mutself,v:V) -> bool{
 self.inner.insert(v)

compiler/rustc_middle/src/ty/mod.rs

@@ -33,6 +33,7 @@ use rustc_data_structures::fx::{FxHashMap, FxHashSet, FxIndexMap, FxIndexSet};
 use rustc_data_structures::intern::Interned;
 use rustc_data_structures::stable_hasher::{HashStable,StableHasher};
 use rustc_data_structures::steal::Steal;
+use rustc_data_structures::unord::UnordMap;
 use rustc_errors::{Diag,ErrorGuaranteed};
 use rustc_hir::LangItem;
 use rustc_hir::def::{CtorKind,CtorOf,DefKind,DocLinkResMap,LifetimeRes,Res};
@@ -168,7 +169,7 @@ pub struct ResolverGlobalCtxt {
 /// Item with a given `LocalDefId` was defined during macro expansion with ID `ExpnId`.
 pubexpn_that_defined:FxHashMap<LocalDefId,ExpnId>,
 pubeffective_visibilities:EffectiveVisibilities,
-pubextern_crate_map:FxHashMap<LocalDefId,CrateNum>,
+pubextern_crate_map:UnordMap<LocalDefId,CrateNum>,
 pubmaybe_unused_trait_imports:FxIndexSet<LocalDefId>,
 pubmodule_children:LocalDefIdMap<Vec<ModChild>>,
 pubglob_map:FxHashMap<LocalDefId,FxHashSet<Symbol>>,

compiler/rustc_resolve/src/build_reduced_graph.rs

@@ -1115,6 +1115,7 @@ impl<'a, 'ra, 'tcx> BuildReducedGraphVisitor<'a, 'ra, 'tcx> {
 }
 });
 }else{
+#[allow(rustc::potential_query_instability)]// FIXME
 for ident in single_imports.iter().cloned(){
 let result = self.r.maybe_resolve_ident_in_module(
 ModuleOrUniformRoot::Module(module),

compiler/rustc_resolve/src/diagnostics.rs

@@ -6,6 +6,7 @@ use rustc_ast::{
 };
 use rustc_ast_pretty::pprust;
 use rustc_data_structures::fx::FxHashSet;
+use rustc_data_structures::unord::UnordSet;
 use rustc_errors::codes::*;
 use rustc_errors::{
 Applicability,Diag,DiagCtxtHandle,ErrorGuaranteed,MultiSpan,SuggestionStyle,
@@ -1467,6 +1468,7 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> {
 return;
 }
 
+#[allow(rustc::potential_query_instability)]// FIXME
 let unused_macro = self.unused_macros.iter().find_map(|(def_id,(_, unused_ident))| {
 if unused_ident.name == ident.name{Some((def_id, unused_ident))}else{None}
 });
@@ -2863,18 +2865,11 @@ fn show_candidates(
 }else{
 // Get the unique item kinds and if there's only one, we use the right kind name
 // instead of the more generic "items".
-letmutkinds = accessible_path_strings
+let kinds = accessible_path_strings
 .iter()
 .map(|(_, descr, _, _, _)| *descr)
-.collect::<FxHashSet<&str>>()
-.into_iter();
-let kind = ifletSome(kind) = kinds.next()
- && letNone = kinds.next()
-{
- kind
-}else{
-"item"
-};
+.collect::<UnordSet<&str>>();
+let kind = ifletSome(kind) = kinds.get_only(){ kind }else{"item"};
 let s = if kind.ends_with('s'){"es"}else{"s"};
 
 ("one of these", kind, s,String::new(),"")

compiler/rustc_resolve/src/ident.rs

@@ -946,6 +946,7 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> {
 
 // Check if one of single imports can still define the name,
 // if it can then our result is not determined and can be invalidated.
+#[allow(rustc::potential_query_instability)]// FIXME
 for single_import in&resolution.single_imports{
 if ignore_import == Some(*single_import){
 // This branch handles a cycle in single imports.

compiler/rustc_resolve/src/late.rs

@@ -18,6 +18,7 @@ use rustc_ast::visit::{
 };
 use rustc_ast::*;
 use rustc_data_structures::fx::{FxHashMap,FxHashSet,FxIndexMap};
+use rustc_data_structures::unord::{UnordMap,UnordSet};
 use rustc_errors::codes::*;
 use rustc_errors::{
 Applicability,DiagArgValue,ErrorGuaranteed,IntoDiagArg,StashKey,Suggestions,
@@ -47,8 +48,6 @@ mod diagnostics;
 
 typeRes = def::Res<NodeId>;
 
-typeIdentMap<T> = FxHashMap<Ident,T>;
-
 use diagnostics::{ElisionFnParameter,LifetimeElisionCandidate,MissingLifetime};
 
 #[derive(Copy,Clone,Debug)]
@@ -273,8 +272,8 @@ impl RibKind<'_> {
 /// resolving, the name is looked up from inside out.
 #[derive(Debug)]
 pub(crate)structRib<'ra,R = Res>{
-pubbindings:IdentMap<R>,
-pubpatterns_with_skipped_bindings:FxHashMap<DefId,Vec<(Span,Result<(),ErrorGuaranteed>)>>,
+pubbindings:FxHashMap<Ident,R>,
+pubpatterns_with_skipped_bindings:UnordMap<DefId,Vec<(Span,Result<(),ErrorGuaranteed>)>>,
 pubkind:RibKind<'ra>,
 }
 
@@ -1605,12 +1604,12 @@ impl<'a, 'ast, 'ra: 'ast, 'tcx> LateResolutionVisitor<'a, 'ast, 'ra, 'tcx> {
 // for better diagnostics.
 letmut forward_ty_ban_rib_const_param_ty = Rib{
 bindings: forward_ty_ban_rib.bindings.clone(),
-patterns_with_skipped_bindings:FxHashMap::default(),
+patterns_with_skipped_bindings:Default::default(),
 kind:RibKind::ForwardGenericParamBan(ForwardGenericParamBanReason::ConstParamTy),
 };
 letmut forward_const_ban_rib_const_param_ty = Rib{
 bindings: forward_const_ban_rib.bindings.clone(),
-patterns_with_skipped_bindings:FxHashMap::default(),
+patterns_with_skipped_bindings:Default::default(),
 kind:RibKind::ForwardGenericParamBan(ForwardGenericParamBanReason::ConstParamTy),
 };
 // We'll ban these with a `ConstParamTy` rib, so just clear these ribs for better
@@ -2334,7 +2333,7 @@ impl<'a, 'ast, 'ra: 'ast, 'tcx> LateResolutionVisitor<'a, 'ast, 'ra, 'tcx> {
 let local_candidates = self.lifetime_elision_candidates.take();
 
 ifletSome(candidates) = local_candidates {
-let distinct:FxHashSet<_> = candidates.iter().map(|(res, _)| *res).collect();
+let distinct:UnordSet<_> = candidates.iter().map(|(res, _)| *res).collect();
 let lifetime_count = distinct.len();
 if lifetime_count != 0{
  parameter_info.push(ElisionFnParameter{
@@ -2358,14 +2357,13 @@ impl<'a, 'ast, 'ra: 'ast, 'tcx> LateResolutionVisitor<'a, 'ast, 'ra, 'tcx> {
 }
 }));
 }
-letmut distinct_iter = distinct.into_iter();
-ifletSome(res) = distinct_iter.next(){
+if !distinct.is_empty(){
 match elision_lifetime {
 // We are the first parameter to bind lifetimes.
 Elision::None => {
-ifdistinct_iter.next().is_none(){
+ifletSome(res) = distinct.get_only(){
 // We have a single lifetime => success.
- elision_lifetime = Elision::Param(res)
+ elision_lifetime = Elision::Param(*res)
 }else{
 // We have multiple lifetimes => error.
  elision_lifetime = Elision::Err;
@@ -2890,6 +2888,7 @@ impl<'a, 'ast, 'ra: 'ast, 'tcx> LateResolutionVisitor<'a, 'ast, 'ra, 'tcx> {
 break;
 }
 
+#[allow(rustc::potential_query_instability)]// FIXME
  seen_bindings
 .extend(parent_rib.bindings.keys().map(|ident| (*ident, ident.span)));
 }
@@ -4004,7 +4003,7 @@ impl<'a, 'ast, 'ra: 'ast, 'tcx> LateResolutionVisitor<'a, 'ast, 'ra, 'tcx> {
 }
 }
 
-fninnermost_rib_bindings(&mutself,ns:Namespace) -> &mutIdentMap<Res>{
+fninnermost_rib_bindings(&mutself,ns:Namespace) -> &mutFxHashMap<Ident,Res>{
 &mutself.ribs[ns].last_mut().unwrap().bindings
 }
 
@@ -5202,6 +5201,7 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> {
 letmut late_resolution_visitor = LateResolutionVisitor::new(self);
  late_resolution_visitor.resolve_doc_links(&krate.attrs,MaybeExported::Ok(CRATE_NODE_ID));
  visit::walk_crate(&mut late_resolution_visitor, krate);
+#[allow(rustc::potential_query_instability)]// FIXME
 for(id, span)in late_resolution_visitor.diag_metadata.unused_labels.iter(){
 self.lint_buffer.buffer_lint(
  lint::builtin::UNUSED_LABELS,

compiler/rustc_resolve/src/late/diagnostics.rs

@@ -830,6 +830,7 @@ impl<'ast, 'ra: 'ast, 'tcx> LateResolutionVisitor<'_, 'ast, 'ra, 'tcx> {
 ifletSome(rib) = &self.last_block_rib
  && letRibKind::Normal = rib.kind
 {
+#[allow(rustc::potential_query_instability)]// FIXME
 for(ident,&res)in&rib.bindings{
 ifletRes::Local(_) = res
  && path.len() == 1
@@ -1018,6 +1019,7 @@ impl<'ast, 'ra: 'ast, 'tcx> LateResolutionVisitor<'_, 'ast, 'ra, 'tcx> {
 ifletSome(err_code) = err.code{
 if err_code == E0425{
 for label_rib in&self.label_ribs{
+#[allow(rustc::potential_query_instability)]// FIXME
 for(label_ident, node_id)in&label_rib.bindings{
 let ident = path.last().unwrap().ident;
 ifformat!("'{ident}") == label_ident.to_string(){
@@ -1177,7 +1179,10 @@ impl<'ast, 'ra: 'ast, 'tcx> LateResolutionVisitor<'_, 'ast, 'ra, 'tcx> {
 let[segment] = path else{return};
 letNone = following_seg else{return};
 for rib inself.ribs[ValueNS].iter().rev(){
-for(def_id, spans)in&rib.patterns_with_skipped_bindings{
+let patterns_with_skipped_bindings = self.r.tcx.with_stable_hashing_context(|hcx| {
+ rib.patterns_with_skipped_bindings.to_sorted(&hcx,true)
+});
+for(def_id, spans)in patterns_with_skipped_bindings {
 ifletDefKind::Struct | DefKind::Variant = self.r.tcx.def_kind(*def_id)
  && letSome(fields) = self.r.field_idents(*def_id)
 {
@@ -2052,7 +2057,7 @@ impl<'ast, 'ra: 'ast, 'tcx> LateResolutionVisitor<'_, 'ast, 'ra, 'tcx> {
 ifself
 .r
 .extern_crate_map
-.iter()
+.items()
 // FIXME: This doesn't include impls like `impl Default for String`.
 .flat_map(|(_, crate_)| self.r.tcx.implementations_of_trait((*crate_, default_trait)))
 .filter_map(|(_, simplified_self_ty)| *simplified_self_ty)
@@ -2261,6 +2266,7 @@ impl<'ast, 'ra: 'ast, 'tcx> LateResolutionVisitor<'_, 'ast, 'ra, 'tcx> {
 };
 
 // Locals and type parameters
+#[allow(rustc::potential_query_instability)]// FIXME
 for(ident,&res)in&rib.bindings{
 iffilter_fn(res) && ident.span.ctxt() == rib_ctxt {
  names.push(TypoSuggestion::typo_from_ident(*ident, res));
@@ -2788,6 +2794,7 @@ impl<'ast, 'ra: 'ast, 'tcx> LateResolutionVisitor<'_, 'ast, 'ra, 'tcx> {
 let within_scope = self.is_label_valid_from_rib(rib_index);
 
 let rib = &self.label_ribs[rib_index];
+#[allow(rustc::potential_query_instability)]// FIXME
 let names = rib
 .bindings
 .iter()
@@ -2799,6 +2806,7 @@ impl<'ast, 'ra: 'ast, 'tcx> LateResolutionVisitor<'_, 'ast, 'ra, 'tcx> {
 // Upon finding a similar name, get the ident that it was from - the span
 // contained within helps make a useful diagnostic. In addition, determine
 // whether this candidate is within scope.
+#[allow(rustc::potential_query_instability)]// FIXME
 let(ident, _) = rib.bindings.iter().find(|(ident, _)| ident.name == symbol).unwrap();
 (*ident, within_scope)
 })

compiler/rustc_resolve/src/lib.rs

@@ -9,7 +9,6 @@
 // tidy-alphabetical-start
 #![allow(internal_features)]
 #![allow(rustc::diagnostic_outside_of_impl)]
-#![allow(rustc::potential_query_instability)]
 #![allow(rustc::untranslatable_diagnostic)]
 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")]
 #![doc(rust_logo)]
@@ -47,6 +46,7 @@ use rustc_data_structures::fx::{FxHashMap, FxHashSet, FxIndexMap, FxIndexSet};
 use rustc_data_structures::intern::Interned;
 use rustc_data_structures::steal::Steal;
 use rustc_data_structures::sync::FreezeReadGuard;
+use rustc_data_structures::unord::UnordMap;
 use rustc_errors::{Applicability,Diag,ErrCode,ErrorGuaranteed};
 use rustc_expand::base::{DeriveResolution,SyntaxExtension,SyntaxExtensionKind};
 use rustc_feature::BUILTIN_ATTRIBUTES;
@@ -1046,7 +1046,7 @@ pub struct Resolver<'ra, 'tcx> {
 graph_root:Module<'ra>,
 
 prelude:Option<Module<'ra>>,
-extern_prelude:FxHashMap<Ident,ExternPreludeEntry<'ra>>,
+extern_prelude:FxIndexMap<Ident,ExternPreludeEntry<'ra>>,
 
 /// N.B., this is used only for better diagnostics, not name resolution itself.
 field_names:LocalDefIdMap<Vec<Ident>>,
@@ -1079,7 +1079,7 @@ pub struct Resolver<'ra, 'tcx> {
 extra_lifetime_params_map:NodeMap<Vec<(Ident,NodeId,LifetimeRes)>>,
 
 /// `CrateNum` resolutions of `extern crate` items.
-extern_crate_map:FxHashMap<LocalDefId,CrateNum>,
+extern_crate_map:UnordMap<LocalDefId,CrateNum>,
 module_children:LocalDefIdMap<Vec<ModChild>>,
 trait_map:NodeMap<Vec<TraitCandidate>>,
 
@@ -1102,7 +1102,7 @@ pub struct Resolver<'ra, 'tcx> {
 /// some AST passes can generate identifiers that only resolve to local or
 /// lang items.
 empty_module:Module<'ra>,
-module_map:FxHashMap<DefId,Module<'ra>>,
+module_map:FxIndexMap<DefId,Module<'ra>>,
 binding_parent_modules:FxHashMap<NameBinding<'ra>,Module<'ra>>,
 
 underscore_disambiguator:u32,
@@ -1136,7 +1136,7 @@ pub struct Resolver<'ra, 'tcx> {
 macro_names:FxHashSet<Ident>,
 builtin_macros:FxHashMap<Symbol,BuiltinMacroState>,
 registered_tools:&'tcxRegisteredTools,
-macro_use_prelude:FxHashMap<Symbol,NameBinding<'ra>>,
+macro_use_prelude:FxIndexMap<Symbol,NameBinding<'ra>>,
 macro_map:FxHashMap<DefId,MacroData>,
 dummy_ext_bang:Arc<SyntaxExtension>,
 dummy_ext_derive:Arc<SyntaxExtension>,
@@ -1145,7 +1145,7 @@ pub struct Resolver<'ra, 'tcx> {
 ast_transform_scopes:FxHashMap<LocalExpnId,Module<'ra>>,
 unused_macros:FxHashMap<LocalDefId,(NodeId,Ident)>,
 /// A map from the macro to all its potentially unused arms.
-unused_macro_rules:FxIndexMap<LocalDefId,FxHashMap<usize,(Ident,Span)>>,
+unused_macro_rules:FxIndexMap<LocalDefId,UnordMap<usize,(Ident,Span)>>,
 proc_macro_stubs:FxHashSet<LocalDefId>,
 /// Traces collected during macro resolution and validated when it's complete.
 single_segment_macro_resolutions:
@@ -1259,7 +1259,7 @@ impl<'ra> ResolverArenas<'ra> {
 expn_id:ExpnId,
 span:Span,
 no_implicit_prelude:bool,
-module_map:&mutFxHashMap<DefId,Module<'ra>>,
+module_map:&mutFxIndexMap<DefId,Module<'ra>>,
 module_self_bindings:&mutFxHashMap<Module<'ra>,NameBinding<'ra>>,
 ) -> Module<'ra>{
 let module = Module(Interned::new_unchecked(self.modules.alloc(ModuleData::new(
@@ -1404,7 +1404,7 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> {
 arenas:&'raResolverArenas<'ra>,
 ) -> Resolver<'ra,'tcx>{
 let root_def_id = CRATE_DEF_ID.to_def_id();
-letmut module_map = FxHashMap::default();
+letmut module_map = FxIndexMap::default();
 letmut module_self_bindings = FxHashMap::default();
 let graph_root = arenas.new_module(
 None,
@@ -1421,8 +1421,8 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> {
 ExpnId::root(),
 DUMMY_SP,
 true,
-&mutFxHashMap::default(),
-&mutFxHashMap::default(),
+&mutDefault::default(),
+&mutDefault::default(),
 );
 
 letmut def_id_to_node_id = IndexVec::default();
@@ -1437,7 +1437,7 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> {
 letmut invocation_parents = FxHashMap::default();
  invocation_parents.insert(LocalExpnId::ROOT,InvocationParent::ROOT);
 
-letmut extern_prelude:FxHashMap<Ident,ExternPreludeEntry<'_>> = tcx
+letmut extern_prelude:FxIndexMap<Ident,ExternPreludeEntry<'_>> = tcx
 .sess
 .opts
 .externs
@@ -1536,7 +1536,7 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> {
 macro_names:FxHashSet::default(),
 builtin_macros:Default::default(),
  registered_tools,
-macro_use_prelude:FxHashMap::default(),
+macro_use_prelude:Default::default(),
 macro_map:FxHashMap::default(),
 dummy_ext_bang:Arc::new(SyntaxExtension::dummy_bang(edition)),
 dummy_ext_derive:Arc::new(SyntaxExtension::dummy_derive(edition)),

compiler/rustc_resolve/src/macros.rs

@@ -323,6 +323,7 @@ impl<'ra, 'tcx> ResolverExpand for Resolver<'ra, 'tcx> {
 }
 
 fncheck_unused_macros(&mutself){
+#[allow(rustc::potential_query_instability)]// FIXME
 for(_,&(node_id, ident))inself.unused_macros.iter(){
 self.lint_buffer.buffer_lint(
 UNUSED_MACROS,
@@ -333,10 +334,7 @@ impl<'ra, 'tcx> ResolverExpand for Resolver<'ra, 'tcx> {
 }
 
 for(&def_id, unused_arms)inself.unused_macro_rules.iter(){
-letmut unused_arms = unused_arms.iter().collect::<Vec<_>>();
- unused_arms.sort_by_key(|&(&arm_i, _)| arm_i);
-
-for(&arm_i,&(ident, rule_span))in unused_arms {
+for(&arm_i,&(ident, rule_span))in unused_arms.to_sorted_stable_ord(){
 ifself.unused_macros.contains_key(&def_id){
 // We already lint the entire macro as unused
 continue;