[naga spv-in] OpImageWrite allows input other than Vector4.

naga/src/front/spv/image.rs

@@ -309,11 +309,64 @@ impl<I: Iterator<Item = u32>> super::Frontend<I> {
         let value_lexp = self.lookup_expression.lookup(value_id)?;
         let value = self.get_expr_handle(value_id, value_lexp, ctx, emitter, block, body_idx);
 
+        // In hlsl etc, the write value may not be the vector 4.
+        let swizzled_value = match ctx.type_arena[image_ty].inner {
+            crate::TypeInner::Image {
+                dim: _,
+                arrayed: _,
+                class: crate::ImageClass::Storage { format, access: _ },
+            } => match format {
+                crate::StorageFormat::Rg8Unorm
+                | crate::StorageFormat::Rg8Snorm
+                | crate::StorageFormat::Rg8Uint
+                | crate::StorageFormat::Rg8Sint
+                | crate::StorageFormat::Rg16Uint
+                | crate::StorageFormat::Rg16Sint
+                | crate::StorageFormat::Rg16Float
+                | crate::StorageFormat::Rg32Uint
+                | crate::StorageFormat::Rg32Sint
+                | crate::StorageFormat::Rg32Float => Some(crate::Expression::Swizzle {
+                    size: crate::VectorSize::Quad,
+                    vector: value,
+                    pattern: [
+                        crate::SwizzleComponent::X,
+                        crate::SwizzleComponent::Y,
+                        crate::SwizzleComponent::Y,
+                        crate::SwizzleComponent::Y,
+                    ],
+                }),
+
+                crate::StorageFormat::R8Unorm
+                | crate::StorageFormat::R8Snorm
+                | crate::StorageFormat::R8Uint
+                | crate::StorageFormat::R8Sint
+                | crate::StorageFormat::R16Uint
+                | crate::StorageFormat::R16Sint
+                | crate::StorageFormat::R16Float
+                | crate::StorageFormat::R32Uint
+                | crate::StorageFormat::R32Sint
+                | crate::StorageFormat::R32Float
+                | crate::StorageFormat::R16Unorm
+                | crate::StorageFormat::R16Snorm => Some(crate::Expression::Splat {
+                    value,
+                    size: crate::VectorSize::Quad,
+                }),
+                _ => None,
+            },
+            _ => None,
+        };
+
+        let value_patched = if let Some(s) = swizzled_value {
+            ctx.expressions.append(s, crate::Span::default())
+        } else {
+            value
+        };
+
         Ok(crate::Statement::ImageStore {
             image: image_lexp.handle,
             coordinate,
             array_index,
-            value,
+            value: value_patched,
         })
     }