bench: WGSL parsing

Cargo.toml

@@ -37,6 +37,10 @@ hlsl-out = []
 span = ["codespan-reporting"]
 validate = []
 
+[[bench]]
+name = "criterion"
+harness = false
+
 # MSRV warnings:
 # - arbitrary 1.0.3 requires Rust-1.51
 # - bitflags 1.3 requires Rust-1.46
@@ -59,6 +63,7 @@ pp-rs = { version = "0.2.1", optional = true }
 hexf-parse = { version = "0.2.1", optional = true }
 
 [dev-dependencies]
+criterion = { version = "0.3", features = ["html_reports"] }
 diff = "0.1"
 ron = "0.7"
 serde = { version = "1.0", features = ["derive"] }

benches/criterion.rs

@@ -0,0 +1,46 @@
+use criterion::*;
+use std::{fs, path::PathBuf};
+
+fn gather_inputs(folder: &str, extension: &str) -> Vec<String> {
+    let mut list = Vec::new();
+    let read_dir = PathBuf::from(env!("CARGO_MANIFEST_DIR"))
+        .join(folder)
+        .read_dir()
+        .unwrap();
+    for file_entry in read_dir {
+        match file_entry {
+            Ok(entry) => match entry.path().extension() {
+                Some(ostr) if &*ostr == extension => {
+                    let input = fs::read_to_string(entry.path()).unwrap_or_default();
+                    list.push(input);
+                }
+                _ => continue,
+            },
+            Err(e) => {
+                log::warn!("Skipping file: {:?}", e);
+                continue;
+            }
+        }
+    }
+    list
+}
+
+fn frontends(c: &mut Criterion) {
+    let mut group = c.benchmark_group("tests/in");
+    group.bench_function("wgsl", |b| {
+        let inputs = gather_inputs("tests/in", "wgsl");
+        let mut parser = naga::front::wgsl::Parser::new();
+        b.iter(move || {
+            for input in inputs.iter() {
+                parser.parse(input).unwrap();
+            }
+        });
+    });
+}
+
+fn validation(_c: &mut Criterion) {}
+
+fn backends(_c: &mut Criterion) {}
+
+criterion_group!(criterion, frontends, validation, backends,);
+criterion_main!(criterion);