Add #[spirv(invariant)]

.github/workflows/ci.yaml

@@ -98,6 +98,8 @@ jobs:
  run: cargo fetch --locked
  - name: Rustfmt
  run: cargo fmt --all -- --check
+ - name: Rustfmt tests
+ run: rustfmt --check tests/ui/**/*.rs
  - name: Clippy
  run: .github/workflows/clippy.sh
 

crates/rustc_codegen_spirv/src/attr.rs

@@ -91,6 +91,7 @@ pub enum SpirvAttribute {
  DescriptorSet(u32),
  Binding(u32),
  Flat,
+ Invariant,
 
  // `fn`/closure attributes:
  UnrollLoops,
@@ -122,6 +123,7 @@ pub struct AggregatedSpirvAttributes {
  pub descriptor_set: Option<Spanned<u32>>,
  pub binding: Option<Spanned<u32>>,
  pub flat: Option<Spanned<()>>,
+ pub invariant: Option<Spanned<()>>,
 
  // `fn`/closure attributes:
  pub unroll_loops: Option<Spanned<()>>,
@@ -204,6 +206,7 @@ impl AggregatedSpirvAttributes {
  ),
  Binding(value) => try_insert(&mut self.binding, value, span, "#[spirv(binding)]"),
  Flat => try_insert(&mut self.flat, (), span, "#[spirv(flat)]"),
+ Invariant => try_insert(&mut self.invariant, (), span, "#[spirv(invariant)]"),
  UnrollLoops => try_insert(&mut self.unroll_loops, (), span, "#[spirv(unroll_loops)]"),
  }
  }
@@ -285,7 +288,8 @@ impl CheckSpirvAttrVisitor<'_> {
  | SpirvAttribute::Builtin(_)
  | SpirvAttribute::DescriptorSet(_)
  | SpirvAttribute::Binding(_)
- | SpirvAttribute::Flat => match target {
+ | SpirvAttribute::Flat
+ | SpirvAttribute::Invariant => match target {
  Target::Param => {
  let parent_hir_id = self.tcx.hir().get_parent_node(hir_id);
  let parent_is_entry_point =

crates/rustc_codegen_spirv/src/codegen_cx/entry.rs

@@ -261,6 +261,16 @@ impl<'tcx> CodegenCx<'tcx> {
  self.emit_global()
  .decorate(variable, Decoration::Flat, std::iter::empty());
  }
+ if let Some(invariant) = attrs.invariant {
+ self.emit_global()
+ .decorate(variable, Decoration::Invariant, std::iter::empty());
+ if storage_class != StorageClass::Output {
+ self.tcx.sess.span_err(
+ invariant.span,
+ "#[spirv(invariant)] is only valid on Output variables",
+ );
+ }
+ }
 
  // FIXME(eddyb) check whether the storage class is compatible with the
  // specific shader stage of this entry-point, and any decorations

crates/rustc_codegen_spirv/src/symbols.rs

@@ -336,6 +336,7 @@ impl Symbols {
  ),
  ("block", SpirvAttribute::Block),
  ("flat", SpirvAttribute::Flat),
+ ("invariant", SpirvAttribute::Invariant),
  (
  "sampled_image",
  SpirvAttribute::IntrinsicType(IntrinsicType::SampledImage),

docs/src/attributes.md

@@ -94,5 +94,16 @@ Example:
 
 ```rust
 #[spirv(fragment)]
-fn main(#[spirv(flat)] obj: &u32) { }
+fn main(#[spirv(flat)] obj: u32) { }
+```
+
+## Invariant
+
+The invariant attribute corresponds to the invariant keyword in glsl. It can only be applied to output variables.
+
+Example:
+
+```rust
+#[spirv(vertex)]
+fn main(#[spirv(invariant)] var: &mut f32) { }
 ```

tests/ui/hello_world.rs

@@ -4,5 +4,4 @@
 use spirv_std as _;
 
 #[spirv(fragment)]
-pub fn main() {
-}
+pub fn main() {}

tests/ui/lang/control_flow/for_range.rs

@@ -4,6 +4,5 @@ use spirv_std as _;
 
 #[spirv(fragment)]
 pub fn main(i: i32) {
- for _ in 0..i {
- }
+ for _ in 0..i {}
 }

tests/ui/lang/control_flow/for_with_custom_range_iter.rs

@@ -6,8 +6,8 @@
 
 // build-pass
 
-use spirv_std::num_traits::Num;
 use core::ops::Range;
+use spirv_std::num_traits::Num;
 
 struct RangeIter<T>(Range<T>);
 
@@ -26,7 +26,5 @@ impl<T: Num + Ord + Copy> Iterator for RangeIter<T> {
 
 #[spirv(fragment)]
 pub fn main(i: i32) {
- for _ in RangeIter(0..i) {
- }
+ for _ in RangeIter(0..i) {}
 }
-

tests/ui/lang/control_flow/if.rs

@@ -4,7 +4,5 @@ use spirv_std as _;
 
 #[spirv(fragment)]
 pub fn main(i: i32) {
- if i > 0 {
-
- }
+ if i > 0 {}
 }

tests/ui/lang/control_flow/if_else.rs

@@ -5,8 +5,6 @@ use spirv_std as _;
 #[spirv(fragment)]
 pub fn main(i: i32) {
  if i > 0 {
-
  } else {
-
  }
 }

tests/ui/lang/control_flow/if_else_if_else.rs

@@ -5,10 +5,7 @@ use spirv_std as _;
 #[spirv(fragment)]
 pub fn main(i: i32) {
  if i > 0 {
-
  } else if i < 0 {
-
  } else {
-
  }
 }

tests/ui/lang/control_flow/if_if.rs

@@ -5,8 +5,6 @@ use spirv_std as _;
 #[spirv(fragment)]
 pub fn main(i: i32) {
  if i > 0 {
- if i < 10 {
-
- }
+ if i < 10 {}
  }
 }

tests/ui/lang/control_flow/if_while.rs

@@ -5,7 +5,6 @@ use spirv_std as _;
 #[spirv(fragment)]
 pub fn main(i: i32) {
  if i == 0 {
- while i < 10 {
- }
+ while i < 10 {}
  }
 }

tests/ui/lang/control_flow/ifx2.rs

@@ -4,10 +4,6 @@ use spirv_std as _;
 
 #[spirv(fragment)]
 pub fn main(i: i32) {
- if i > 0 {
-
- }
- if i > 1 {
-
- }
+ if i > 0 {}
+ if i > 1 {}
 }

tests/ui/lang/control_flow/while.rs

@@ -4,6 +4,5 @@ use spirv_std as _;
 
 #[spirv(fragment)]
 pub fn main(i: i32) {
- while i < 10 {
- }
+ while i < 10 {}
 }

tests/ui/lang/control_flow/while_while.rs

@@ -5,7 +5,6 @@ use spirv_std as _;
 #[spirv(fragment)]
 pub fn main(i: i32) {
  while i < 20 {
- while i < 10 {
- }
+ while i < 10 {}
  }
 }

tests/ui/lang/core/mem/create_unitialized_memory.rs

@@ -8,7 +8,9 @@ const MAYBEI32: MaybeUninit<&i32> = MaybeUninit::<&i32>::uninit();
 
 pub fn create_uninit_and_write() {
  let mut maybei32 = MAYBEI32;
- unsafe { maybei32.as_mut_ptr().write(&0); }
+ unsafe {
+ maybei32.as_mut_ptr().write(&0);
+ }
  let _maybei32 = unsafe { maybei32.assume_init() };
 }
 

tests/ui/lang/core/ptr/allocate_const_scalar.rs

@@ -8,7 +8,7 @@
 use spirv_std as _;
 
 use core::ptr::Unique;
-const POINTER: Unique<[u8;4]> = Unique::<[u8; 4]>::dangling();
+const POINTER: Unique<[u8; 4]> = Unique::<[u8; 4]>::dangling();
 
 #[spirv(fragment)]
 pub fn main() {

tests/ui/spirv-attr/invalid-storage-class.rs

@@ -9,4 +9,5 @@ fn _entry(
  #[spirv(private)] _: (),
  #[spirv(function)] _: (),
  #[spirv(generic)] _: (),
-) {}
+) {
+}