Improve clippy CI and fix some benchmark clippy warnings (#1081)

* add clippy job for linting benchmark code

* fix warning that will become a hard error in the future

* fix some benchmark clippy warnings

Not sure if those warnings are useful to begin with ...

* apply rustfmt

.github/workflows/rust.yml

@@ -403,6 +403,8 @@ jobs:
         run: cargo clippy --workspace --no-default-features -- -D warnings
       - name: Clippy (tests)
         run: cargo clippy --workspace --tests -- -D warnings
+      - name: Clippy (benches)
+        run: cargo clippy --workspace --benches -- -D warnings
       - name: Clippy (fuzz)
         run: pushd fuzz && cargo clippy -- -D warnings && popd
 

crates/wasmi/benches/benches.rs

@@ -590,21 +590,21 @@ fn bench_instantiate_contract(c: &mut Criterion, name: &str, path: &str) {
             .define(
                 "seal0",
                 "seal_value_transferred",
-                Func::wrap(&mut store, |_0: i32, _1: i32| unimplemented!()),
+                Func::wrap(&mut store, |_0: i32, _1: i32| ()),
             )
             .unwrap();
         linker
             .define(
                 "seal0",
                 "seal_input",
-                Func::wrap(&mut store, |_0: i32, _1: i32| unimplemented!()),
+                Func::wrap(&mut store, |_0: i32, _1: i32| ()),
             )
             .unwrap();
         linker
             .define(
                 "seal0",
                 "seal_caller",
-                Func::wrap(&mut store, |_0: i32, _1: i32| unimplemented!()),
+                Func::wrap(&mut store, |_0: i32, _1: i32| ()),
             )
             .unwrap();
         linker
@@ -629,10 +629,7 @@ fn bench_instantiate_contract(c: &mut Criterion, name: &str, path: &str) {
             .define(
                 "seal0",
                 "seal_deposit_event",
-                Func::wrap(
-                    &mut store,
-                    |_0: i32, _1: i32, _2: i32, _3: i32| unimplemented!(),
-                ),
+                Func::wrap(&mut store, |_0: i32, _1: i32, _2: i32, _3: i32| ()),
             )
             .unwrap();
         linker
@@ -662,14 +659,14 @@ fn bench_instantiate_contract(c: &mut Criterion, name: &str, path: &str) {
             .define(
                 "seal0",
                 "seal_return",
-                Func::wrap(&mut store, |_0: i32, _1: i32, _2: i32| unimplemented!()),
+                Func::wrap(&mut store, |_0: i32, _1: i32, _2: i32| ()),
             )
             .unwrap();
         linker
             .define(
                 "seal0",
                 "seal_hash_blake2_256",
-                Func::wrap(&mut store, |_0: i32, _1: i32, _2: i32| unimplemented!()),
+                Func::wrap(&mut store, |_0: i32, _1: i32, _2: i32| ()),
             )
             .unwrap();
         b.iter(|| {
@@ -1386,7 +1383,7 @@ fn bench_execute_vec_add(c: &mut Criterion) {
     fn test_for<A, B>(
         b: &mut Bencher,
         vec_add: Func,
-        mut store: &mut Store<()>,
+        store: &mut Store<()>,
         mem: Memory,
         len: usize,
         vec_a: A,
@@ -1404,16 +1401,24 @@ fn bench_execute_vec_add(c: &mut Criterion) {
         let ptr_b = ptr_a + len_a;
 
         // Reset `result` buffer to zeros:
-        mem.data_mut(&mut store)[ptr_result..ptr_result + (len * size_of::<i32>())].fill(0);
+        mem.data_mut(&mut *store)[ptr_result..ptr_result + (len * size_of::<i32>())].fill(0);
         // Initialize `a` buffer:
         for (n, a) in vec_a.into_iter().take(len).enumerate() {
-            mem.write(&mut store, ptr_a + (n * size_of::<i32>()), &a.to_le_bytes())
-                .unwrap();
+            mem.write(
+                &mut *store,
+                ptr_a + (n * size_of::<i32>()),
+                &a.to_le_bytes(),
+            )
+            .unwrap();
         }
         // Initialize `b` buffer:
         for (n, b) in vec_b.into_iter().take(len).enumerate() {
-            mem.write(&mut store, ptr_b + (n * size_of::<i32>()), &b.to_le_bytes())
-                .unwrap();
+            mem.write(
+                &mut *store,
+                ptr_b + (n * size_of::<i32>()),
+                &b.to_le_bytes(),
+            )
+            .unwrap();
         }
 
         // Prepare parameters and all Wasm `vec_add`:
@@ -1424,25 +1429,25 @@ fn bench_execute_vec_add(c: &mut Criterion) {
             Val::I32(len as i32),
         ];
         b.iter(|| {
-            vec_add.call(&mut store, &params, &mut []).unwrap();
+            vec_add.call(&mut *store, &params, &mut []).unwrap();
         });
 
         // Validate the result buffer:
         for n in 0..len {
             let mut buffer4 = [0x00; 4];
             let mut buffer8 = [0x00; 8];
             let a = {
-                mem.read(&store, ptr_a + (n * size_of::<i32>()), &mut buffer4)
+                mem.read(&*store, ptr_a + (n * size_of::<i32>()), &mut buffer4)
                     .unwrap();
                 i32::from_le_bytes(buffer4)
             };
             let b = {
-                mem.read(&store, ptr_b + (n * size_of::<i32>()), &mut buffer4)
+                mem.read(&*store, ptr_b + (n * size_of::<i32>()), &mut buffer4)
                     .unwrap();
                 i32::from_le_bytes(buffer4)
             };
             let actual_result = {
-                mem.read(&store, ptr_result + (n * size_of::<i64>()), &mut buffer8)
+                mem.read(&*store, ptr_result + (n * size_of::<i64>()), &mut buffer8)
                     .unwrap();
                 i64::from_le_bytes(buffer8)
             };