user0/rust
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Auto merge of #145358 - Kobzol:symbol-name-sort, r=nnethercote

Browse source 
Sort mono items by symbol name

Trying to claw back cycles/branch/cache miss losses from https://github.com/rust-lang/rust/pull/144722.
This commit is contained in:
bors 2025-08-22 07:13:07 +00:00
commit 831e291d3b
2 changed files with 68 additions and 51 deletions
Download patch file Download diff file Expand all files Collapse all files

23
compiler/rustc_middle/src/mir/mono.rs
View file

@ -548,10 +548,27 @@ impl<'tcx> CodegenUnit<'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;
// In this case, we do not need to keep the items in any specific order, as the input
// is already deterministic.
//
// However, it seems that moving related things (such as different
// monomorphizations of the same function) close to one another is actually beneficial
// for LLVM performance.
// LLVM will codegen the items in the order we pass them to it, and when it handles
// similar things in succession, it seems that it leads to better cache utilization,
// less branch mispredictions and in general to better performance.
// For example, if we have functions `a`, `c::<u32>`, `b`, `c::<i16>`, `d` and
// `c::<bool>`, it seems that it helps LLVM's performance to codegen the three `c`
// instantiations right after one another, as they will likely reference similar types,
// call similar functions, etc.
//
// See https://github.com/rust-lang/rust/pull/145358 for more details.
//
// Sorting by symbol name should not incur any new non-determinism.
items.sort_by_cached_key(|&(i, _)| i.symbol_name(tcx));
} else {
items.sort_by_cached_key(|&(i, _)| item_sort_key(tcx, i));
}
items.sort_by_cached_key(|&(i, _)| item_sort_key(tcx, i));
items
}

96
tests/ui/intrinsics/non-integer-atomic.stderr
View file

@ -4,20 +4,20 @@ error[E0511]: invalid monomorphization of `atomic_load` intrinsic: expected basi
LL | intrinsics::atomic_load::<_, { SeqCst }>(p);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error[E0511]: invalid monomorphization of `atomic_xchg` intrinsic: expected basic integer or pointer type, found `&dyn Fn()`
--> $DIR/non-integer-atomic.rs:65:5
|
LL | intrinsics::atomic_xchg::<_, { SeqCst }>(p, v);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error[E0511]: invalid monomorphization of `atomic_load` intrinsic: expected basic integer or pointer 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 or pointer 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 or pointer type, found `[u8; 100]`
--> $DIR/non-integer-atomic.rs:85:5
error[E0511]: invalid monomorphization of `atomic_xchg` intrinsic: expected basic integer or pointer type, found `Foo`
--> $DIR/non-integer-atomic.rs:45:5
|
LL | intrinsics::atomic_xchg::<_, { SeqCst }>(p, v);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@ -28,12 +28,48 @@ error[E0511]: invalid monomorphization of `atomic_cxchg` intrinsic: expected bas
LL | intrinsics::atomic_cxchg::<_, { SeqCst }, { SeqCst }>(p, v, v);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error[E0511]: invalid monomorphization of `atomic_store` intrinsic: expected basic integer or pointer type, found `&dyn Fn()`
--> $DIR/non-integer-atomic.rs:60:5
|
LL | intrinsics::atomic_store::<_, { SeqCst }>(p, v);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error[E0511]: invalid monomorphization of `atomic_cxchg` intrinsic: expected basic integer or pointer 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_store` intrinsic: expected basic integer or pointer type, found `Foo`
--> $DIR/non-integer-atomic.rs:40:5
|
LL | intrinsics::atomic_store::<_, { SeqCst }>(p, v);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error[E0511]: invalid monomorphization of `atomic_load` intrinsic: expected basic integer or pointer type, found `[u8; 100]`
--> $DIR/non-integer-atomic.rs:75:5
|
LL | intrinsics::atomic_load::<_, { SeqCst }>(p);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error[E0511]: invalid monomorphization of `atomic_xchg` intrinsic: expected basic integer or pointer type, found `[u8; 100]`
--> $DIR/non-integer-atomic.rs:85:5
|
LL | intrinsics::atomic_xchg::<_, { SeqCst }>(p, v);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error[E0511]: invalid monomorphization of `atomic_load` intrinsic: expected basic integer or pointer type, found `bool`
--> $DIR/non-integer-atomic.rs:15:5
|
LL | intrinsics::atomic_load::<_, { SeqCst }>(p);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error[E0511]: invalid monomorphization of `atomic_xchg` intrinsic: expected basic integer or pointer type, found `bool`
--> $DIR/non-integer-atomic.rs:25:5
|
LL | intrinsics::atomic_xchg::<_, { SeqCst }>(p, v);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error[E0511]: invalid monomorphization of `atomic_cxchg` intrinsic: expected basic integer or pointer type, found `[u8; 100]`
--> $DIR/non-integer-atomic.rs:90:5
|
@ -46,53 +82,17 @@ error[E0511]: invalid monomorphization of `atomic_store` intrinsic: expected bas
LL | intrinsics::atomic_store::<_, { SeqCst }>(p, v);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error[E0511]: invalid monomorphization of `atomic_store` intrinsic: expected basic integer or pointer type, found `bool`
--> $DIR/non-integer-atomic.rs:20:5
|
LL | intrinsics::atomic_store::<_, { SeqCst }>(p, v);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error[E0511]: invalid monomorphization of `atomic_xchg` intrinsic: expected basic integer or pointer type, found `&dyn Fn()`
--> $DIR/non-integer-atomic.rs:65:5
|
LL | intrinsics::atomic_xchg::<_, { SeqCst }>(p, v);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error[E0511]: invalid monomorphization of `atomic_load` intrinsic: expected basic integer or pointer type, found `[u8; 100]`
--> $DIR/non-integer-atomic.rs:75:5
|
LL | intrinsics::atomic_load::<_, { SeqCst }>(p);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error[E0511]: invalid monomorphization of `atomic_load` intrinsic: expected basic integer or pointer type, found `bool`
--> $DIR/non-integer-atomic.rs:15:5
|
LL | intrinsics::atomic_load::<_, { SeqCst }>(p);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error[E0511]: invalid monomorphization of `atomic_cxchg` intrinsic: expected basic integer or pointer type, found `bool`
--> $DIR/non-integer-atomic.rs:30:5
|
LL | intrinsics::atomic_cxchg::<_, { SeqCst }, { SeqCst }>(p, v, v);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error[E0511]: invalid monomorphization of `atomic_cxchg` intrinsic: expected basic integer or pointer type, found `Foo`
--> $DIR/non-integer-atomic.rs:50:5
error[E0511]: invalid monomorphization of `atomic_store` intrinsic: expected basic integer or pointer type, found `bool`
--> $DIR/non-integer-atomic.rs:20:5
|
LL | intrinsics::atomic_cxchg::<_, { SeqCst }, { SeqCst }>(p, v, v);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error[E0511]: invalid monomorphization of `atomic_xchg` intrinsic: expected basic integer or pointer 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 or pointer type, found `bool`
--> $DIR/non-integer-atomic.rs:25:5
|
LL | intrinsics::atomic_xchg::<_, { SeqCst }>(p, v);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
LL | intrinsics::atomic_store::<_, { SeqCst }>(p, v);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: aborting due to 16 previous errors