reflect: allow validation of shaders without reflecting against semantics

librashader-reflect/src/back/mod.rs

@@ -32,6 +32,9 @@ pub trait CompileShader<T: OutputTarget> {
     type Context;
 
     /// Consume the object and return the compiled output of the shader.
+    ///
+    /// The shader should either be reflected or validated as
+    /// [ReflectShader] before being compiled, or the results may not be valid.
     fn compile(
         self,
         options: Self::Options,
@@ -139,6 +142,10 @@ where
     ) -> Result<ShaderReflection, ShaderReflectError> {
         self.backend.reflect(pass_number, semantics)
     }
+
+    fn validate(&mut self) -> Result<(), ShaderReflectError> {
+        self.backend.validate()
+    }
 }
 
 impl<T: ReflectShader + ?Sized> ReflectShader for Box<T> {
@@ -149,6 +156,10 @@ impl<T: ReflectShader + ?Sized> ReflectShader for Box<T> {
     ) -> Result<ShaderReflection, ShaderReflectError> {
         (**self).reflect(pass_number, semantics)
     }
+
+    fn validate(&mut self) -> Result<(), ShaderReflectError> {
+        (**self).validate()
+    }
 }
 
 impl<O, T> CompileShader<T> for Box<O>

librashader-reflect/src/back/spirv.rs

@@ -72,6 +72,10 @@ impl ReflectShader for WriteSpirV {
     ) -> Result<ShaderReflection, ShaderReflectError> {
         self.reflect.reflect(pass_number, semantics)
     }
+
+    fn validate(&mut self) -> Result<(), ShaderReflectError> {
+        self.reflect.validate()
+    }
 }
 
 impl CompileShader<SPIRV> for WriteSpirV {

librashader-reflect/src/reflect/cross/mod.rs

@@ -160,7 +160,7 @@ impl<T> CrossReflect<T>
 where
     T: spirv_cross2::compile::CompilableTarget,
 {
-    fn validate(
+    fn validate_semantics(
         &self,
         vertex_res: &AllResources,
         fragment_res: &AllResources,
@@ -714,7 +714,7 @@ where
     ) -> Result<ShaderReflection, ShaderReflectError> {
         let vertex_res = self.vertex.shader_resources()?.all_resources()?;
         let fragment_res = self.fragment.shader_resources()?.all_resources()?;
-        self.validate(&vertex_res, &fragment_res)?;
+        self.validate_semantics(&vertex_res, &fragment_res)?;
 
         let vertex_ubo = vertex_res.uniform_buffers.first();
         let fragment_ubo = fragment_res.uniform_buffers.first();
@@ -797,6 +797,23 @@ where
             meta,
         })
     }
+
+    fn validate(&mut self) -> Result<(), ShaderReflectError> {
+        let vertex_res = self.vertex.shader_resources()?.all_resources()?;
+        let fragment_res = self.fragment.shader_resources()?.all_resources()?;
+        self.validate_semantics(&vertex_res, &fragment_res)?;
+        let vertex_ubo = vertex_res.uniform_buffers.first();
+        let fragment_ubo = fragment_res.uniform_buffers.first();
+
+        self.reflect_ubos(vertex_ubo, fragment_ubo)?;
+
+        let vertex_push = vertex_res.push_constant_buffers.first();
+        let fragment_push = fragment_res.push_constant_buffers.first();
+
+        self.reflect_push_constant_buffer(vertex_push, fragment_push)?;
+
+        Ok(())
+    }
 }
 
 #[cfg(test)]

librashader-reflect/src/reflect/mod.rs

@@ -25,6 +25,9 @@ pub trait ReflectShader {
         pass_number: usize,
         semantics: &ShaderSemantics,
     ) -> Result<ShaderReflection, ShaderReflectError>;
+
+    /// Validate the shader without doing reflection against a set of semantics.
+    fn validate(&mut self) -> Result<(), ShaderReflectError>;
 }
 
 pub use semantics::ShaderReflection;

librashader-reflect/src/reflect/naga/mod.rs

@@ -239,7 +239,7 @@ impl ValidateTypeSemantics<&TypeInner> for TextureSemantics {
 
 impl NagaReflect {
     fn reflect_ubos(
-        &mut self,
+        &self,
         vertex_ubo: Option<Handle<GlobalVariable>>,
         fragment_ubo: Option<Handle<GlobalVariable>>,
     ) -> Result<Option<BufferReflection<u32>>, ShaderReflectError> {
@@ -429,7 +429,7 @@ impl NagaReflect {
         }
     }
 
-    fn validate(&self) -> Result<(), ShaderReflectError> {
+    fn validate_semantics(&self) -> Result<(), ShaderReflectError> {
         // Verify types
         if self.vertex.global_variables.iter().any(|(_, gv)| {
             let ty = &self.vertex.types[gv.ty];
@@ -882,7 +882,7 @@ impl ReflectShader for NagaReflect {
         pass_number: usize,
         semantics: &ShaderSemantics,
     ) -> Result<ShaderReflection, ShaderReflectError> {
-        self.validate()?;
+        self.validate_semantics()?;
 
         // Validate verifies that there's only one uniform block.
         let vertex_ubo = self
@@ -1012,6 +1012,36 @@ impl ReflectShader for NagaReflect {
             meta,
         })
     }
+
+    fn validate(&mut self) -> Result<(), ShaderReflectError> {
+        self.validate_semantics()?;
+        let vertex_push = self
+            .vertex
+            .global_variables
+            .iter()
+            .find_map(|(handle, gv)| {
+                if gv.space == AddressSpace::PushConstant {
+                    Some(handle)
+                } else {
+                    None
+                }
+            });
+
+        let fragment_push = self
+            .fragment
+            .global_variables
+            .iter()
+            .find_map(|(handle, gv)| {
+                if gv.space == AddressSpace::PushConstant {
+                    Some(handle)
+                } else {
+                    None
+                }
+            });
+
+        self.reflect_push_constant_buffer(vertex_push, fragment_push)?;
+        Ok(())
+    }
 }
 
 #[cfg(test)]

librashader-reflect/src/reflect/presets.rs

@@ -219,7 +219,10 @@ impl ShaderSemantics {
     /// Create pass semantics for a single pass in the given shader preset.
     ///
     /// This is meant as a convenience function for reflection use only.
-    pub fn create_pass_semantics<E>(preset: &ShaderPreset, index: usize) -> Result<ShaderSemantics, E>
+    pub fn create_pass_semantics<E>(
+        preset: &ShaderPreset,
+        index: usize,
+    ) -> Result<ShaderSemantics, E>
     where
         E: From<ShaderReflectError>,
         E: From<PreprocessError>,
@@ -268,6 +271,4 @@ impl ShaderSemantics {
             texture_semantics,
         })
     }
-
 }
-