1 files changed, 91 insertions, 0 deletions
diff --git a/third_party/rust/naga/src/back/spv/layout.rs b/third_party/rust/naga/src/back/spv/layout.rs
new file mode 100644
index 0000000000..006e785317
--- /dev/null
+++ b/third_party/rust/naga/src/back/spv/layout.rs
@@ -0,0 +1,91 @@
+use crate::back::spv::{Instruction, LogicalLayout, PhysicalLayout};
+use spirv::*;
+use std::iter;
+
+impl PhysicalLayout {
+    pub(super) fn new(header: &crate::Header) -> Self {
+        let version: Word = ((header.version.0 as u32) << 16)
+            | ((header.version.1 as u32) << 8)
+            | header.version.2 as u32;
+
+        PhysicalLayout {
+            magic_number: MAGIC_NUMBER,
+            version,
+            generator: header.generator,
+            bound: 0,
+            instruction_schema: 0x0u32,
+        }
+    }
+
+    pub(super) fn in_words(&self, sink: &mut impl Extend<Word>) {
+        sink.extend(iter::once(self.magic_number));
+        sink.extend(iter::once(self.version));
+        sink.extend(iter::once(self.generator));
+        sink.extend(iter::once(self.bound));
+        sink.extend(iter::once(self.instruction_schema));
+    }
+
+    pub(super) fn supports_storage_buffers(&self) -> bool {
+        self.version >= 0x10300
+    }
+}
+
+impl LogicalLayout {
+    pub(super) fn in_words(&self, sink: &mut impl Extend<Word>) {
+        sink.extend(self.capabilities.iter().cloned());
+        sink.extend(self.extensions.iter().cloned());
+        sink.extend(self.ext_inst_imports.iter().cloned());
+        sink.extend(self.memory_model.iter().cloned());
+        sink.extend(self.entry_points.iter().cloned());
+        sink.extend(self.execution_modes.iter().cloned());
+        sink.extend(self.debugs.iter().cloned());
+        sink.extend(self.annotations.iter().cloned());
+        sink.extend(self.declarations.iter().cloned());
+        sink.extend(self.function_declarations.iter().cloned());
+        sink.extend(self.function_definitions.iter().cloned());
+    }
+}
+
+impl Instruction {
+    pub(super) fn new(op: Op) -> Self {
+        Instruction {
+            op,
+            wc: 1, // Always start at 1 for the first word (OP + WC),
+            type_id: None,
+            result_id: None,
+            operands: vec![],
+        }
+    }
+
+    #[allow(clippy::panic)]
+    pub(super) fn set_type(&mut self, id: Word) {
+        assert!(self.type_id.is_none(), "Type can only be set once");
+        self.type_id = Some(id);
+        self.wc += 1;
+    }
+
+    #[allow(clippy::panic)]
+    pub(super) fn set_result(&mut self, id: Word) {
+        assert!(self.result_id.is_none(), "Result can only be set once");
+        self.result_id = Some(id);
+        self.wc += 1;
+    }
+
+    pub(super) fn add_operand(&mut self, operand: Word) {
+        self.operands.push(operand);
+        self.wc += 1;
+    }
+
+    pub(super) fn add_operands(&mut self, operands: Vec<Word>) {
+        for operand in operands.into_iter() {
+            self.add_operand(operand)
+        }
+    }
+
+    pub(super) fn to_words(&self, sink: &mut impl Extend<Word>) {
+        sink.extend(Some((self.wc << 16 | self.op as u32) as u32));
+        sink.extend(self.type_id);
+        sink.extend(self.result_id);
+        sink.extend(self.operands.iter().cloned());
+    }
+}