Auto merge of #106977 - michaelwoerister:unord_id_collections, r=oli-obk

Use UnordMap and UnordSet for id collections (DefIdMap, LocalDefIdMap, etc)

This PR changes the `rustc_data_structures::define_id_collections!` macro to use `UnordMap` and `UnordSet` instead of `FxHashMap` and `FxHashSet`. This should account for a large portion of hash-maps being used in places where they can cause trouble.

The changes required are moderate but non-zero:
- In some places the collections are extracted into sorted vecs.
- There are a few instances where for-loops have been changed to extends.

~~Let's see what the performance impact is. With a bit more refactoring, we might be able to get rid of some of the additional sorting -- but the change set is already big enough. Unless there's a performance impact, I'd like to do further changes in subsequent PRs.~~

Performance does not seem to be negatively affected ([perf-run here](https://github.com/rust-lang/rust/pull/106977#issuecomment-1396776699)).

Part of [MCP 533](https://github.com/rust-lang/compiler-team/issues/533).

r? `@ghost`

2 files changed, 18 insertions, 11 deletions

diff --git a/compiler/rustc_codegen_ssa/src/back/symbol_export.rs b/compiler/rustc_codegen_ssa/src/back/symbol_export.rs
index 8cb7d74b90d..57a99e74c21 100644
--- a/compiler/rustc_codegen_ssa/src/back/symbol_export.rs
+++ b/compiler/rustc_codegen_ssa/src/back/symbol_export.rs
@@ -173,11 +173,15 @@ fn exported_symbols_provider_local(
         return &[];
     }
 
-    let mut symbols: Vec<_> = tcx
-        .reachable_non_generics(LOCAL_CRATE)
-        .iter()
-        .map(|(&def_id, &info)| (ExportedSymbol::NonGeneric(def_id), info))
-        .collect();
+    // FIXME: Sorting this is unnecessary since we are sorting later anyway.
+    //        Can we skip the later sorting?
+    let mut symbols: Vec<_> = tcx.with_stable_hashing_context(|hcx| {
+        tcx.reachable_non_generics(LOCAL_CRATE)
+            .to_sorted(&hcx, true)
+            .into_iter()
+            .map(|(&def_id, &info)| (ExportedSymbol::NonGeneric(def_id), info))
+            .collect()
+    });
 
     if tcx.entry_fn(()).is_some() {
         let exported_symbol =
diff --git a/compiler/rustc_codegen_ssa/src/base.rs b/compiler/rustc_codegen_ssa/src/base.rs
index f7312f6fcda..32d3cfe6fc6 100644
--- a/compiler/rustc_codegen_ssa/src/base.rs
+++ b/compiler/rustc_codegen_ssa/src/base.rs
@@ -964,16 +964,19 @@ pub fn provide(providers: &mut Providers) {
         };
 
         let (defids, _) = tcx.collect_and_partition_mono_items(cratenum);
-        for id in &*defids {
+
+        let any_for_speed = defids.items().any(|id| {
             let CodegenFnAttrs { optimize, .. } = tcx.codegen_fn_attrs(*id);
             match optimize {
-                attr::OptimizeAttr::None => continue,
-                attr::OptimizeAttr::Size => continue,
-                attr::OptimizeAttr::Speed => {
-                    return for_speed;
-                }
+                attr::OptimizeAttr::None | attr::OptimizeAttr::Size => false,
+                attr::OptimizeAttr::Speed => true,
             }
+        });
+
+        if any_for_speed {
+            return for_speed;
         }
+
         tcx.sess.opts.optimize
     };
 }