Fix parallel rustc not being reproducible due to unstable sorts of items

compiler/rustc_interface/src/tests.rs

@@ -689,6 +689,7 @@ fn test_unstable_options_tracking_hash() {
     // Make sure that changing an [UNTRACKED] option leaves the hash unchanged.
     // tidy-alphabetical-start
     untracked!(assert_incr_state, Some(String::from("loaded")));
+    untracked!(codegen_source_order, true);
     untracked!(deduplicate_diagnostics, false);
     untracked!(dump_dep_graph, true);
     untracked!(dump_mir, Some(String::from("abc")));

compiler/rustc_middle/src/mir/mono.rs

@@ -12,7 +12,6 @@ use rustc_hashes::Hash128;
 use rustc_hir::ItemId;
 use rustc_hir::attrs::InlineAttr;
 use rustc_hir::def_id::{CrateNum, DefId, DefIdSet, LOCAL_CRATE};
-use rustc_index::Idx;
 use rustc_macros::{HashStable, TyDecodable, TyEncodable};
 use rustc_query_system::ich::StableHashingContext;
 use rustc_session::config::OptLevel;
@@ -526,44 +525,50 @@ impl<'tcx> CodegenUnit<'tcx> {
         tcx: TyCtxt<'tcx>,
     ) -> Vec<(MonoItem<'tcx>, MonoItemData)> {
         // The codegen tests rely on items being process in the same order as
-        // they appear in the file, so for local items, we sort by node_id first
+        // they appear in the file, so for local items, we sort by span first
         #[derive(PartialEq, Eq, PartialOrd, Ord)]
-        struct ItemSortKey<'tcx>(Option<usize>, SymbolName<'tcx>);
-
+        struct ItemSortKey<'tcx>(Option<Span>, SymbolName<'tcx>);
+
+        // We only want to take HirIds of user-defines instances into account.
+        // The others don't matter for the codegen tests and can even make item
+        // order unstable.
+        fn local_item_id<'tcx>(item: MonoItem<'tcx>) -> Option<DefId> {
+            match item {
+                MonoItem::Fn(ref instance) => match instance.def {
+                    InstanceKind::Item(def) => def.as_local().map(|_| def),
+                    InstanceKind::VTableShim(..)
+                    | InstanceKind::ReifyShim(..)
+                    | InstanceKind::Intrinsic(..)
+                    | InstanceKind::FnPtrShim(..)
+                    | InstanceKind::Virtual(..)
+                    | InstanceKind::ClosureOnceShim { .. }
+                    | InstanceKind::ConstructCoroutineInClosureShim { .. }
+                    | InstanceKind::DropGlue(..)
+                    | InstanceKind::CloneShim(..)
+                    | InstanceKind::ThreadLocalShim(..)
+                    | InstanceKind::FnPtrAddrShim(..)
+                    | InstanceKind::AsyncDropGlue(..)
+                    | InstanceKind::FutureDropPollShim(..)
+                    | InstanceKind::AsyncDropGlueCtorShim(..) => None,
+                },
+                MonoItem::Static(def_id) => def_id.as_local().map(|_| def_id),
+                MonoItem::GlobalAsm(item_id) => Some(item_id.owner_id.def_id.to_def_id()),
+            }
+        }
         fn item_sort_key<'tcx>(tcx: TyCtxt<'tcx>, item: MonoItem<'tcx>) -> ItemSortKey<'tcx> {
             ItemSortKey(
-                match item {
-                    MonoItem::Fn(ref instance) => {
-                        match instance.def {
-                            // We only want to take HirIds of user-defined
-                            // instances into account. The others don't matter for
-                            // the codegen tests and can even make item order
-                            // unstable.
-                            InstanceKind::Item(def) => def.as_local().map(Idx::index),
-                            InstanceKind::VTableShim(..)
-                            | InstanceKind::ReifyShim(..)
-                            | InstanceKind::Intrinsic(..)
-                            | InstanceKind::FnPtrShim(..)
-                            | InstanceKind::Virtual(..)
-                            | InstanceKind::ClosureOnceShim { .. }
-                            | InstanceKind::ConstructCoroutineInClosureShim { .. }
-                            | InstanceKind::DropGlue(..)
-                            | InstanceKind::CloneShim(..)
-                            | InstanceKind::ThreadLocalShim(..)
-                            | InstanceKind::FnPtrAddrShim(..)
-                            | InstanceKind::AsyncDropGlue(..)
-                            | InstanceKind::FutureDropPollShim(..)
-                            | InstanceKind::AsyncDropGlueCtorShim(..) => None,
-                        }
-                    }
-                    MonoItem::Static(def_id) => def_id.as_local().map(Idx::index),
-                    MonoItem::GlobalAsm(item_id) => Some(item_id.owner_id.def_id.index()),
-                },
+                local_item_id(item)
+                    .map(|def_id| tcx.def_span(def_id).find_ancestor_not_from_macro())
+                    .flatten(),
                 item.symbol_name(tcx),
             )
         }
 
         let mut items: Vec<_> = self.items().iter().map(|(&i, &data)| (i, data)).collect();
+        if !tcx.sess.opts.unstable_opts.codegen_source_order {
+            // It's already deterministic, so we can just use it.
+            return items;
+        }
         items.sort_by_cached_key(|&(i, _)| item_sort_key(tcx, i));
         items
     }

compiler/rustc_session/src/options.rs

@@ -2168,6 +2168,8 @@ options! {
         "hash algorithm of source files used to check freshness in cargo (`blake3` or `sha256`)"),
     codegen_backend: Option<String> = (None, parse_opt_string, [TRACKED],
         "the backend to use"),
+    codegen_source_order: bool = (false, parse_bool, [UNTRACKED],
+        "emit mono items in the order of spans in source files (default: no)"),
     contract_checks: Option<bool> = (None, parse_opt_bool, [TRACKED],
         "emit runtime checks for contract pre- and post-conditions (default: no)"),
     coverage_options: CoverageOptions = (CoverageOptions::default(), parse_coverage_options, [TRACKED],

src/doc/unstable-book/src/compiler-flags/codegen-source-order.md

@@ -0,0 +1,17 @@
+# `codegen-source-order`
+
+---
+
+This feature allows you to have a predictive and
+deterministic order for items after codegen.
+
+For every `CodegenUnit`, local `MonoItem`s would
+be sorted by `(Span, DefPath, SymbolName)`, which
+makes codegen tests rely on the order of items in
+source files work.
+
+Note: If you would like to use it, you have to
+manually sort items that are generated by a macro
+in lexicographical order in source files, because
+of the same spans owned by all items of a macro.
+So we have to distinguish them by `DefPath`s.

src/tools/compiletest/src/runtest.rs

@@ -1695,6 +1695,10 @@ impl<'test> TestCx<'test> {
             }
             TestMode::Assembly | TestMode::Codegen => {
                 rustc.arg("-Cdebug-assertions=no");
+                // For assembly and codegen tests, we want to use the same order
+                // of the items of a codegen unit as the source order, so that
+                // we can compare the output with the source code through filecheck.
+                rustc.arg("-Zcodegen-source-order");
             }
             TestMode::Crashes => {
                 set_mir_dump_dir(&mut rustc);

tests/ui/intrinsics/bad-intrinsic-monomorphization.stderr

@@ -1,20 +1,20 @@
-error[E0511]: invalid monomorphization of `cttz` intrinsic: expected basic integer type, found `Foo`
-  --> $DIR/bad-intrinsic-monomorphization.rs:16:5
+error[E0511]: invalid monomorphization of `simd_add` intrinsic: expected SIMD input type, found non-SIMD `Foo`
+  --> $DIR/bad-intrinsic-monomorphization.rs:26:5
    |
-LL |     intrinsics::cttz(v)
-   |     ^^^^^^^^^^^^^^^^^^^
+LL |     intrinsics::simd::simd_add(a, b)
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error[E0511]: invalid monomorphization of `fadd_fast` intrinsic: expected basic float type, found `Foo`
   --> $DIR/bad-intrinsic-monomorphization.rs:21:5
    |
 LL |     intrinsics::fadd_fast(a, b)
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error[E0511]: invalid monomorphization of `simd_add` intrinsic: expected SIMD input type, found non-SIMD `Foo`
-  --> $DIR/bad-intrinsic-monomorphization.rs:26:5
+error[E0511]: invalid monomorphization of `cttz` intrinsic: expected basic integer type, found `Foo`
+  --> $DIR/bad-intrinsic-monomorphization.rs:16:5
    |
-LL |     intrinsics::simd::simd_add(a, b)
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+LL |     intrinsics::cttz(v)
+   |     ^^^^^^^^^^^^^^^^^^^
 
 error: aborting due to 3 previous errors
 

tests/ui/intrinsics/non-integer-atomic.stderr

@@ -1,59 +1,53 @@
-error[E0511]: invalid monomorphization of `atomic_load` intrinsic: expected basic integer type, found `bool`
-  --> $DIR/non-integer-atomic.rs:15:5
+error[E0511]: invalid monomorphization of `atomic_load` intrinsic: expected basic integer type, found `&dyn Fn()`
+  --> $DIR/non-integer-atomic.rs:55:5
    |
 LL |     intrinsics::atomic_load::<_, { SeqCst }>(p);
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error[E0511]: invalid monomorphization of `atomic_store` intrinsic: expected basic integer type, found `bool`
-  --> $DIR/non-integer-atomic.rs:20:5
+error[E0511]: invalid monomorphization of `atomic_load` intrinsic: expected basic integer type, found `Foo`
+  --> $DIR/non-integer-atomic.rs:35:5
+   |
+LL |     intrinsics::atomic_load::<_, { SeqCst }>(p);
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error[E0511]: invalid monomorphization of `atomic_store` intrinsic: expected basic integer type, found `&dyn Fn()`
+  --> $DIR/non-integer-atomic.rs:60:5
    |
 LL |     intrinsics::atomic_store::<_, { SeqCst }>(p, v);
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error[E0511]: invalid monomorphization of `atomic_xchg` intrinsic: expected basic integer type, found `bool`
-  --> $DIR/non-integer-atomic.rs:25:5
+error[E0511]: invalid monomorphization of `atomic_xchg` intrinsic: expected basic integer type, found `[u8; 100]`
+  --> $DIR/non-integer-atomic.rs:85:5
    |
 LL |     intrinsics::atomic_xchg::<_, { SeqCst }>(p, v);
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error[E0511]: invalid monomorphization of `atomic_cxchg` intrinsic: expected basic integer type, found `bool`
-  --> $DIR/non-integer-atomic.rs:30:5
+error[E0511]: invalid monomorphization of `atomic_cxchg` intrinsic: expected basic integer type, found `&dyn Fn()`
+  --> $DIR/non-integer-atomic.rs:70:5
    |
 LL |     intrinsics::atomic_cxchg::<_, { SeqCst }, { SeqCst }>(p, v, v);
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error[E0511]: invalid monomorphization of `atomic_load` intrinsic: expected basic integer type, found `Foo`
-  --> $DIR/non-integer-atomic.rs:35:5
-   |
-LL |     intrinsics::atomic_load::<_, { SeqCst }>(p);
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-
 error[E0511]: invalid monomorphization of `atomic_store` intrinsic: expected basic integer type, found `Foo`
   --> $DIR/non-integer-atomic.rs:40:5
    |
 LL |     intrinsics::atomic_store::<_, { SeqCst }>(p, v);
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error[E0511]: invalid monomorphization of `atomic_xchg` intrinsic: expected basic integer type, found `Foo`
-  --> $DIR/non-integer-atomic.rs:45:5
-   |
-LL |     intrinsics::atomic_xchg::<_, { SeqCst }>(p, v);
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-
-error[E0511]: invalid monomorphization of `atomic_cxchg` intrinsic: expected basic integer type, found `Foo`
-  --> $DIR/non-integer-atomic.rs:50:5
+error[E0511]: invalid monomorphization of `atomic_cxchg` intrinsic: expected basic integer type, found `[u8; 100]`
+  --> $DIR/non-integer-atomic.rs:90:5
    |
 LL |     intrinsics::atomic_cxchg::<_, { SeqCst }, { SeqCst }>(p, v, v);
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error[E0511]: invalid monomorphization of `atomic_load` intrinsic: expected basic integer type, found `&dyn Fn()`
-  --> $DIR/non-integer-atomic.rs:55:5
+error[E0511]: invalid monomorphization of `atomic_store` intrinsic: expected basic integer type, found `[u8; 100]`
+  --> $DIR/non-integer-atomic.rs:80:5
    |
-LL |     intrinsics::atomic_load::<_, { SeqCst }>(p);
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+LL |     intrinsics::atomic_store::<_, { SeqCst }>(p, v);
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error[E0511]: invalid monomorphization of `atomic_store` intrinsic: expected basic integer type, found `&dyn Fn()`
-  --> $DIR/non-integer-atomic.rs:60:5
+error[E0511]: invalid monomorphization of `atomic_store` intrinsic: expected basic integer type, found `bool`
+  --> $DIR/non-integer-atomic.rs:20:5
    |
 LL |     intrinsics::atomic_store::<_, { SeqCst }>(p, v);
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -64,36 +58,42 @@ error[E0511]: invalid monomorphization of `atomic_xchg` intrinsic: expected basi
 LL |     intrinsics::atomic_xchg::<_, { SeqCst }>(p, v);
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error[E0511]: invalid monomorphization of `atomic_cxchg` intrinsic: expected basic integer type, found `&dyn Fn()`
-  --> $DIR/non-integer-atomic.rs:70:5
-   |
-LL |     intrinsics::atomic_cxchg::<_, { SeqCst }, { SeqCst }>(p, v, v);
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-
 error[E0511]: invalid monomorphization of `atomic_load` intrinsic: expected basic integer type, found `[u8; 100]`
   --> $DIR/non-integer-atomic.rs:75:5
    |
 LL |     intrinsics::atomic_load::<_, { SeqCst }>(p);
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error[E0511]: invalid monomorphization of `atomic_store` intrinsic: expected basic integer type, found `[u8; 100]`
-  --> $DIR/non-integer-atomic.rs:80:5
+error[E0511]: invalid monomorphization of `atomic_load` intrinsic: expected basic integer type, found `bool`
+  --> $DIR/non-integer-atomic.rs:15:5
    |
-LL |     intrinsics::atomic_store::<_, { SeqCst }>(p, v);
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+LL |     intrinsics::atomic_load::<_, { SeqCst }>(p);
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error[E0511]: invalid monomorphization of `atomic_xchg` intrinsic: expected basic integer type, found `[u8; 100]`
-  --> $DIR/non-integer-atomic.rs:85:5
+error[E0511]: invalid monomorphization of `atomic_cxchg` intrinsic: expected basic integer type, found `bool`
+  --> $DIR/non-integer-atomic.rs:30:5
    |
-LL |     intrinsics::atomic_xchg::<_, { SeqCst }>(p, v);
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+LL |     intrinsics::atomic_cxchg::<_, { SeqCst }, { SeqCst }>(p, v, v);
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error[E0511]: invalid monomorphization of `atomic_cxchg` intrinsic: expected basic integer type, found `[u8; 100]`
-  --> $DIR/non-integer-atomic.rs:90:5
+error[E0511]: invalid monomorphization of `atomic_cxchg` intrinsic: expected basic integer type, found `Foo`
+  --> $DIR/non-integer-atomic.rs:50:5
    |
 LL |     intrinsics::atomic_cxchg::<_, { SeqCst }, { SeqCst }>(p, v, v);
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
+error[E0511]: invalid monomorphization of `atomic_xchg` intrinsic: expected basic integer type, found `Foo`
+  --> $DIR/non-integer-atomic.rs:45:5
+   |
+LL |     intrinsics::atomic_xchg::<_, { SeqCst }>(p, v);
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error[E0511]: invalid monomorphization of `atomic_xchg` intrinsic: expected basic integer type, found `bool`
+  --> $DIR/non-integer-atomic.rs:25:5
+   |
+LL |     intrinsics::atomic_xchg::<_, { SeqCst }>(p, v);
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
 error: aborting due to 16 previous errors
 
 For more information about this error, try `rustc --explain E0511`.