[vulkan, spv-out] Remap resource bindings

naga-test/src/lib.rs

@@ -155,6 +155,7 @@ impl SpirvOutParameters {
                 Some(self.capabilities.clone())
             },
             bounds_check_policies,
+            fake_missing_bindings: true,
             binding_map: self.binding_map.clone(),
             zero_initialize_workgroup_memory: spv::ZeroInitializeWorkgroupMemoryMode::Polyfill,
             force_loop_bounding: true,

naga/src/back/spv/mod.rs

@@ -79,6 +79,8 @@ pub enum Error {
     Override,
     #[error(transparent)]
     ResolveArraySizeError(#[from] crate::proc::ResolveArraySizeError),
+    #[error("mapping of {0:?} is missing")]
+    MissingBinding(crate::ResourceBinding),
 }
 
 #[derive(Default)]
@@ -760,6 +762,7 @@ pub struct Writer {
     constant_ids: HandleVec<crate::Expression, Word>,
     cached_constants: crate::FastHashMap<CachedConstant, Word>,
     global_variables: HandleVec<crate::GlobalVariable, GlobalVariable>,
+    fake_missing_bindings: bool,
     binding_map: BindingMap,
 
     // Cached expressions are only meaningful within a BlockContext, but we
@@ -811,10 +814,12 @@ bitflags::bitflags! {
     }
 }
 
-#[derive(Clone, Debug, Default, PartialEq, Eq, Hash)]
+#[derive(Copy, Clone, Debug, Default, PartialEq, Eq, Hash)]
 #[cfg_attr(feature = "serialize", derive(serde::Serialize))]
 #[cfg_attr(feature = "deserialize", derive(serde::Deserialize))]
 pub struct BindingInfo {
+    pub descriptor_set: u32,
+    pub binding: u32,
     /// If the binding is an unsized binding array, this overrides the size.
     pub binding_array_size: Option<u32>,
 }
@@ -839,6 +844,10 @@ pub struct Options<'a> {
     /// Configuration flags for the writer.
     pub flags: WriterFlags,
 
+    /// Don't panic on missing bindings. Instead use fake values for `Binding`
+    /// and `DescriptorSet` decorations. This may result in invalid SPIR-V.
+    pub fake_missing_bindings: bool,
+
     /// Map of resources to information about the binding.
     pub binding_map: BindingMap,
 
@@ -877,6 +886,7 @@ impl Default for Options<'_> {
         Options {
             lang_version: (1, 0),
             flags,
+            fake_missing_bindings: true,
             binding_map: BindingMap::default(),
             capabilities: None,
             bounds_check_policies: BoundsCheckPolicies::default(),

naga/src/back/spv/writer.rs

@@ -87,6 +87,7 @@ impl Writer {
             constant_ids: HandleVec::new(),
             cached_constants: crate::FastHashMap::default(),
             global_variables: HandleVec::new(),
+            fake_missing_bindings: options.fake_missing_bindings,
             binding_map: options.binding_map.clone(),
             saved_cached: CachedExpressions::default(),
             gl450_ext_inst_id,
@@ -149,6 +150,7 @@ impl Writer {
             force_loop_bounding: self.force_loop_bounding,
             use_storage_input_output_16: self.use_storage_input_output_16,
             capabilities_available: take(&mut self.capabilities_available),
+            fake_missing_bindings: self.fake_missing_bindings,
             binding_map: take(&mut self.binding_map),
 
             // Initialized afresh:
@@ -469,6 +471,26 @@ impl Writer {
         })
     }
 
+    /// Resolve the [`BindingInfo`] for a [`crate::ResourceBinding`] from the
+    /// provided [`Writer::binding_map`].
+    ///
+    /// If the specified resource is not present in the binding map this will
+    /// return an error, unless [`Writer::fake_missing_bindings`] is set.
+    fn resolve_resource_binding(
+        &self,
+        res_binding: &crate::ResourceBinding,
+    ) -> Result<BindingInfo, Error> {
+        match self.binding_map.get(res_binding) {
+            Some(target) => Ok(*target),
+            None if self.fake_missing_bindings => Ok(BindingInfo {
+                descriptor_set: res_binding.group,
+                binding: res_binding.binding,
+                binding_array_size: None,
+            }),
+            None => Err(Error::MissingBinding(*res_binding)),
+        }
+    }
+
     /// Emits code for any wrapper functions required by the expressions in ir_function.
     /// The IDs of any emitted functions will be stored in [`Self::wrapped_functions`].
     fn write_wrapped_functions(
@@ -2241,13 +2263,11 @@ impl Writer {
         // and it is failing on 0.
         let mut substitute_inner_type_lookup = None;
         if let Some(ref res_binding) = global_variable.binding {
-            self.decorate(id, Decoration::DescriptorSet, &[res_binding.group]);
-            self.decorate(id, Decoration::Binding, &[res_binding.binding]);
+            let bind_target = self.resolve_resource_binding(res_binding)?;
+            self.decorate(id, Decoration::DescriptorSet, &[bind_target.descriptor_set]);
+            self.decorate(id, Decoration::Binding, &[bind_target.binding]);
 
-            if let Some(&BindingInfo {
-                binding_array_size: Some(remapped_binding_array_size),
-            }) = self.binding_map.get(res_binding)
-            {
+            if let Some(remapped_binding_array_size) = bind_target.binding_array_size {
                 if let crate::TypeInner::BindingArray { base, .. } =
                     ir_module.types[global_variable.ty].inner
                 {

naga/tests/in/wgsl/binding-arrays.toml

@@ -62,5 +62,5 @@ resource_binding = { group = 0, binding = 8 }
 version = [1, 1]
 
 [[spv.binding_map]]
-bind_target = { binding_array_size = 10 }
+bind_target = { descriptor_set = 0, binding = 0, binding_array_size = 10 }
 resource_binding = { group = 0, binding = 0 }

naga/tests/in/wgsl/binding-buffer-arrays.toml

@@ -9,5 +9,5 @@ image = "ReadZeroSkipWrite"
 version = [1, 1]
 
 [[spv.binding_map]]
-bind_target = { binding_array_size = 10 }
+bind_target = { descriptor_set = 0, binding = 0, binding_array_size = 10 }
 resource_binding = { group = 0, binding = 0 }

wgpu-hal/src/vulkan/adapter.rs

@@ -2166,6 +2166,7 @@ impl super::Adapter {
                 force_loop_bounding: true,
                 use_storage_input_output_16: features.contains(wgt::Features::SHADER_F16)
                     && self.phd_features.supports_storage_input_output_16(),
+                fake_missing_bindings: false,
                 // We need to build this separately for each invocation, so just default it out here
                 binding_map: BTreeMap::default(),
                 debug_info: None,