Add initial ONNX importer crate with working op subset

Cargo.toml

@@ -38,6 +38,7 @@ members = [
     "crates/luminal_cpu",
     "crates/luminal_nn",
     "crates/luminal_training",
+    "crates/luminal_onnx",
     "docs/company",
 ]
 exclude = [
@@ -47,3 +48,4 @@ exclude = [
     "crates/luminal_2",
     "demos/flash_attention",
 ]
+

crates/luminal_onnx/Cargo.toml

@@ -0,0 +1,19 @@
+[package]
+name = "luminal_onnx"
+version = "0.1.0"
+edition = "2021"
+license = "MIT OR Apache-2.0"
+description = "ONNX import for Luminal"
+
+[dependencies]
+luminal = { path = "../.." }
+prost = { version = "0.12", default-features = false, features = ["prost-derive"] }
+prost-types = { version = "0.12", default-features = false }
+thiserror = "1"
+
+[build-dependencies]
+prost-build = { version = "0.12" }
+protoc-bin-vendored = "3"
+
+[dev-dependencies]
+tempfile = "3"

crates/luminal_onnx/build.rs

@@ -0,0 +1,11 @@
+fn main() -> Result<(), Box<dyn std::error::Error>> {
+    // Ensure protoc is available without a system install.
+    let protoc = protoc_bin_vendored::protoc_bin_path()?;
+    std::env::set_var("PROTOC", protoc);
+
+    let mut config = prost_build::Config::new();
+    // Use BTreeMap for determinism where prost would generate HashMaps.
+    config.btree_map(["."]);
+    prost_build::compile_protos(&["src/onnx/proto/onnx.proto"], &["src/onnx/proto/"])?;
+    Ok(())
+}

crates/luminal_onnx/src/lib.rs

@@ -0,0 +1,5 @@
+pub mod onnx;
+
+mod load;
+
+pub use load::{import_onnx, OnnxImportError, OnnxImportResult};