Add coherent and volatile memory decorations for storage buffers. (gfx-rs#9168)

Author: atlv24

CHANGELOG.md

@@ -154,6 +154,7 @@ depth_stencil: Some(wgpu::DepthStencilState::stencil(
 - Initial wgsl-in ray tracing pipelines. By @Vecvec in [#8570](https://github.com/gfx-rs/wgpu/pull/8570).
 - wgsl-out ray tracing pipelines. By @Vecvec in [#8970](https://github.com/gfx-rs/wgpu/pull/8970).
 - Allow parsing shaders which make use of `SPV_KHR_non_semantic_info` for debug info. Also removes `naga::front::spv::SUPPORTED_EXT_SETS`. By @inner-daemons in #8827.
+- Added memory decorations for storage buffers: `coherent`, supported on all native backends, and `volatile`, only on Vulkan and GL. By @atlv24 in [#9168](https://github.com/gfx-rs/wgpu/pull/9168).
 
 #### GLES
 

naga/src/back/glsl/mod.rs

@@ -642,4 +642,6 @@ pub fn supported_capabilities() -> valid::Capabilities {
         | Caps::SHADER_FLOAT16_IN_FLOAT32
         | Caps::SHADER_BARYCENTRICS
         | Caps::DRAW_INDEX
+        | Caps::MEMORY_DECORATION_COHERENT
+        | Caps::MEMORY_DECORATION_VOLATILE
 }

naga/src/back/glsl/writer.rs

@@ -699,6 +699,18 @@ impl<'a, W: Write> Writer<'a, W> {
 
         if let crate::AddressSpace::Storage { access } = global.space {
             self.write_storage_access(access)?;
+            if global
+                .memory_decorations
+                .contains(crate::MemoryDecorations::COHERENT)
+            {
+                write!(self.out, "coherent ")?;
+            }
+            if global
+                .memory_decorations
+                .contains(crate::MemoryDecorations::VOLATILE)
+            {
+                write!(self.out, "volatile ")?;
+            }
         }
 
         if let Some(storage_qualifier) = glsl_storage_qualifier(global.space) {

naga/src/back/hlsl/mod.rs

@@ -800,8 +800,10 @@ pub fn supported_capabilities() -> crate::valid::Capabilities {
         // No BUFFER_BINDING_ARRAY_NON_UNIFORM_INDEXING
         | Caps::STORAGE_TEXTURE_BINDING_ARRAY_NON_UNIFORM_INDEXING
         | Caps::STORAGE_BUFFER_BINDING_ARRAY_NON_UNIFORM_INDEXING
-    // No COOPERATIVE_MATRIX
-    // No PER_VERTEX
-    // No RAY_TRACING_PIPELINE
-    // No DRAW_INDEX
+        // No COOPERATIVE_MATRIX
+        // No PER_VERTEX
+        // No RAY_TRACING_PIPELINE
+        // No DRAW_INDEX
+        // No MEMORY_DECORATION_VOLATILE
+        | Caps::MEMORY_DECORATION_COHERENT
 }

naga/src/back/hlsl/writer.rs

@@ -990,6 +990,12 @@ impl<'a, W: fmt::Write> super::Writer<'a, W> {
                 "b"
             }
             crate::AddressSpace::Storage { access } => {
+                if global
+                    .memory_decorations
+                    .contains(crate::MemoryDecorations::COHERENT)
+                {
+                    write!(self.out, "globallycoherent ")?;
+                }
                 let (prefix, register) = if access.contains(crate::StorageAccess::STORE) {
                     ("RW", "u")
                 } else {

naga/src/back/msl/mod.rs

@@ -871,9 +871,11 @@ pub fn supported_capabilities() -> crate::valid::Capabilities {
         | Caps::STORAGE_TEXTURE_BINDING_ARRAY_NON_UNIFORM_INDEXING
         | Caps::STORAGE_BUFFER_BINDING_ARRAY_NON_UNIFORM_INDEXING
         | Caps::COOPERATIVE_MATRIX
-    // No PER_VERTEX
-    // No RAY_TRACING_PIPELINE
-    // No DRAW_INDEX
+        // No PER_VERTEX
+        // No RAY_TRACING_PIPELINE
+        // No DRAW_INDEX
+        // No MEMORY_DECORATION_VOLATILE
+        | Caps::MEMORY_DECORATION_COHERENT
 }
 
 #[test]

naga/src/back/msl/writer.rs

@@ -428,23 +428,32 @@ impl TypedGlobalVariable<'_> {
             first_time: false,
         };
 
-        let (space, access, reference) = match var.space.to_msl_name() {
+        let (coherent, space, access, reference) = match var.space.to_msl_name() {
             Some(space) if self.reference => {
+                let coherent = if var
+                    .memory_decorations
+                    .contains(crate::MemoryDecorations::COHERENT)
+                {
+                    "coherent "
+                } else {
+                    ""
+                };
                 let access = if var.space.needs_access_qualifier()
                     && !self.usage.intersects(valid::GlobalUse::WRITE)
                 {
                     "const"
                 } else {
                     ""
                 };
-                (space, access, "&")
+                (coherent, space, access, "&")
             }
-            _ => ("", "", ""),
+            _ => ("", "", "", ""),
         };
 
         Ok(write!(
             out,
-            "{}{}{}{}{}{} {}",
+            "{}{}{}{}{}{}{} {}",
+            coherent,
             space,
             if space.is_empty() { "" } else { " " },
             ty_name,

naga/src/back/spv/mod.rs

@@ -1191,4 +1191,6 @@ pub fn supported_capabilities() -> crate::valid::Capabilities {
         | Caps::PER_VERTEX
         // No RAY_TRACING_PIPELINE
         | Caps::DRAW_INDEX
+        | Caps::MEMORY_DECORATION_COHERENT
+        | Caps::MEMORY_DECORATION_VOLATILE
 }

naga/src/back/spv/writer.rs

@@ -3288,6 +3288,19 @@ impl Writer {
 
         //self.check(class.required_capabilities())?;
 
+        if global_variable
+            .memory_decorations
+            .contains(crate::MemoryDecorations::COHERENT)
+        {
+            self.decorate(id, Decoration::Coherent, &[]);
+        }
+        if global_variable
+            .memory_decorations
+            .contains(crate::MemoryDecorations::VOLATILE)
+        {
+            self.decorate(id, Decoration::Volatile, &[]);
+        }
+
         if self.flags.contains(WriterFlags::DEBUG) {
             if let Some(ref name) = global_variable.name {
                 self.debugs.push(Instruction::name(id, name));

naga/src/back/wgsl/writer.rs

@@ -1974,6 +1974,19 @@ impl<W: Write> Writer<W> {
             writeln!(self.out)?;
         }
 
+        if global
+            .memory_decorations
+            .contains(crate::MemoryDecorations::COHERENT)
+        {
+            write!(self.out, "@coherent ")?;
+        }
+        if global
+            .memory_decorations
+            .contains(crate::MemoryDecorations::VOLATILE)
+        {
+            write!(self.out, "@volatile ")?;
+        }
+
         // First write global name and address space if supported
         write!(self.out, "var")?;
         let (address, maybe_access) = address_space_str(global.space);