Try #450:

Makefile

@@ -48,18 +48,21 @@ do-install:
 
 test:
 	# We use one thread so the emscripten stdouts doesn't collide
-	cargo test --all --exclude wasmer-runtime-c-api --exclude wasmer-emscripten --exclude wasmer-spectests --exclude wasmer-singlepass-backend --exclude wasmer-wasi -- $(runargs)
+	cargo test --all --exclude wasmer-runtime-c-api --exclude wasmer-emscripten --exclude wasmer-spectests --exclude wasmer-singlepass-backend --exclude wasmer-wasi --exclude wasmer-middleware-common -- $(runargs)
 	# cargo test --all --exclude wasmer-emscripten -- --test-threads=1 $(runargs)
 	cargo test --manifest-path lib/spectests/Cargo.toml --features clif
+	cargo test --manifest-path lib/middleware-common/Cargo.toml --features clif
 	@if [ ! -z "${CIRCLE_JOB}" ]; then rm -f /home/circleci/project/target/debug/deps/libcranelift_wasm* && rm -f /Users/distiller/project/target/debug/deps/libcranelift_wasm*; fi;
 	cargo test --manifest-path lib/spectests/Cargo.toml --features llvm
 	cargo test --manifest-path lib/runtime/Cargo.toml --features llvm
+	cargo test --manifest-path lib/middleware-common/Cargo.toml --features llvm
 	cargo build -p wasmer-runtime-c-api
 	cargo test -p wasmer-runtime-c-api -- --nocapture
 
 test-singlepass:
 	cargo test --manifest-path lib/spectests/Cargo.toml --features singlepass
 	cargo test --manifest-path lib/runtime/Cargo.toml --features singlepass
+	cargo test --manifest-path lib/middleware-common/Cargo.toml --features singlepass
 
 test-emscripten-llvm:
 	cargo test --manifest-path lib/emscripten/Cargo.toml --features llvm -- --test-threads=1 $(runargs)

lib/clif-backend/src/code.rs

@@ -1122,6 +1122,7 @@ impl FunctionCodeGenerator<CodegenError> for CraneliftFunctionCodeGenerator {
     fn feed_event(&mut self, event: Event, _module_info: &ModuleInfo) -> Result<(), CodegenError> {
         let op = match event {
             Event::Wasm(x) => x,
+            Event::WasmOwned(ref x) => x,
             Event::Internal(_x) => {
                 return Ok(());
             }

lib/llvm-backend/src/code.rs

@@ -475,6 +475,7 @@ impl FunctionCodeGenerator<CodegenError> for LLVMFunctionCodeGenerator {
             Event::Internal(_x) => {
                 return Ok(());
             }
+            Event::WasmOwned(ref x) => x,
         };
 
         let mut state = &mut self.state;

lib/llvm-backend/src/intrinsics.rs

@@ -163,6 +163,7 @@ impl Intrinsics {
         let stack_lower_bound_ty = i8_ty;
         let memory_base_ty = i8_ty;
         let memory_bound_ty = void_ty;
+        let internals_ty = i64_ty;
         let local_function_ty = i8_ptr_ty;
 
         let anyfunc_ty = context.struct_type(
@@ -218,6 +219,9 @@ impl Intrinsics {
                 memory_bound_ty
                     .ptr_type(AddressSpace::Generic)
                     .as_basic_type_enum(),
+                internals_ty
+                    .ptr_type(AddressSpace::Generic)
+                    .as_basic_type_enum(),
                 local_function_ty
                     .ptr_type(AddressSpace::Generic)
                     .as_basic_type_enum(),

lib/middleware-common/Cargo.toml

@@ -8,4 +8,20 @@ authors = ["The Wasmer Engineering Team <[email protected]>"]
 edition = "2018"
 
 [dependencies]
-wasmer-runtime-core = { path = "../runtime-core", version = "0.4.2" }
+wasmer-runtime-core = { path = "../runtime-core" }
+wasmer-clif-backend = { path = "../clif-backend", version = "0.4.2" }
+wasmer-llvm-backend = { path = "../llvm-backend", version = "0.4.2", optional = true }
+wasmer-singlepass-backend = { path = "../singlepass-backend", version = "0.4.2", optional = true }
+
+[dev-dependencies]
+wabt = "0.7.4"
+criterion = "0.2"
+
+[features]
+clif = []
+llvm = ["wasmer-llvm-backend"]
+singlepass = ["wasmer-singlepass-backend"]
+
+[[bench]]
+name = "metering_benchmark"
+harness = false

lib/middleware-common/benches/metering_benchmark.rs

@@ -0,0 +1,230 @@
+#[macro_use]
+extern crate criterion;
+
+use criterion::black_box;
+use criterion::{Benchmark, Criterion};
+
+use wabt::wat2wasm;
+
+use wasmer_middleware_common::metering::Metering;
+use wasmer_runtime_core::vm::Ctx;
+use wasmer_runtime_core::{backend::Compiler, compile_with, imports, Func};
+
+//export function add_to(x: i32, y: i32): i32 {
+//   for(var i = 0; i < x; i++){
+//     if(i % 1 == 0){
+//       y += i;
+//     } else {
+//       y *= i
+//     }
+//   }
+//   return y;
+//}
+static WAT: &'static str = r#"
+            (module
+              (type $t0 (func (param i32 i32) (result i32)))
+              (type $t1 (func))
+              (func $add_to (export "add_to") (type $t0) (param $p0 i32) (param $p1 i32) (result i32)
+                (local $l0 i32)
+                block $B0
+                  i32.const 0
+                  set_local $l0
+                  loop $L1
+                    get_local $l0
+                    get_local $p0
+                    i32.lt_s
+                    i32.eqz
+                    br_if $B0
+                    get_local $l0
+                    i32.const 1
+                    i32.rem_s
+                    i32.const 0
+                    i32.eq
+                    if $I2
+                      get_local $p1
+                      get_local $l0
+                      i32.add
+                      set_local $p1
+                    else
+                      get_local $p1
+                      get_local $l0
+                      i32.mul
+                      set_local $p1
+                    end
+                    get_local $l0
+                    i32.const 1
+                    i32.add
+                    set_local $l0
+                    br $L1
+                    unreachable
+                  end
+                  unreachable
+                end
+                get_local $p1)
+              (func $f1 (type $t1))
+              (table $table (export "table") 1 anyfunc)
+              (memory $memory (export "memory") 0)
+              (global $g0 i32 (i32.const 8))
+              (elem (i32.const 0) $f1))
+        "#;
+
+static WAT_GAS: &'static str = r#"
+            (module
+              (type $t0 (func (param i32 i32) (result i32)))
+              (type $t1 (func))
+              (type $t2 (func (param i32)))
+              (import "env" "gas" (func $env.gas (type $t2)))
+              (func $add_to (type $t0) (param $p0 i32) (param $p1 i32) (result i32)
+                (local $l0 i32)
+                i32.const 3
+                call $env.gas
+                block $B0
+                  i32.const 5
+                  call $env.gas
+                  i32.const 0
+                  set_local $l0
+                  loop $L1
+                    i32.const 18
+                    call $env.gas
+                    get_local $l0
+                    get_local $p0
+                    i32.lt_s
+                    i32.eqz
+                    br_if $B0
+                    get_local $l0
+                    i32.const 1
+                    i32.rem_s
+                    i32.const 0
+                    i32.eq
+                    if $I2
+                      i32.const 5
+                      call $env.gas
+                      get_local $p1
+                      get_local $l0
+                      i32.add
+                      set_local $p1
+                    else
+                      i32.const 5
+                      call $env.gas
+                      get_local $p1
+                      get_local $l0
+                      i32.mul
+                      set_local $p1
+                    end
+                    get_local $l0
+                    i32.const 1
+                    i32.add
+                    set_local $l0
+                    br $L1
+                    unreachable
+                  end
+                  unreachable
+                end
+                get_local $p1)
+              (func $f2 (type $t1)
+                i32.const 1
+                call $env.gas)
+              (table $table 1 anyfunc)
+              (memory $memory 0)
+              (global $g0 i32 (i32.const 8))
+              (export "memory" (memory 0))
+              (export "table" (table 0))
+              (export "add_to" (func $add_to))
+              (elem (i32.const 0) $f2))
+        "#;
+
+#[cfg(feature = "llvm")]
+fn get_compiler(limit: u64, metering: bool) -> impl Compiler {
+    use wasmer_llvm_backend::code::LLVMModuleCodeGenerator;
+    use wasmer_runtime_core::codegen::{MiddlewareChain, StreamingCompiler};
+    let c: StreamingCompiler<LLVMModuleCodeGenerator, _, _, _, _> =
+        StreamingCompiler::new(move || {
+            let mut chain = MiddlewareChain::new();
+            if metering {
+                chain.push(Metering::new(limit));
+            }
+            chain
+        });
+
+    c
+}
+
+#[cfg(feature = "singlepass")]
+fn get_compiler(limit: u64, metering: bool) -> impl Compiler {
+    use wasmer_runtime_core::codegen::{MiddlewareChain, StreamingCompiler};
+    use wasmer_singlepass_backend::ModuleCodeGenerator as SinglePassMCG;
+    let c: StreamingCompiler<SinglePassMCG, _, _, _, _> = StreamingCompiler::new(move || {
+        let mut chain = MiddlewareChain::new();
+        if metering {
+            chain.push(Metering::new(limit));
+        }
+        chain
+    });
+    c
+}
+
+#[cfg(not(any(feature = "llvm", feature = "clif", feature = "singlepass")))]
+fn get_compiler(_limit: u64, metering: bool) -> impl Compiler {
+    panic!("compiler not specified, activate a compiler via features");
+    use wasmer_clif_backend::CraneliftCompiler;
+    CraneliftCompiler::new()
+}
+
+#[cfg(feature = "clif")]
+fn get_compiler(_limit: u64, metering: bool) -> impl Compiler {
+    panic!("cranelift does not implement metering");
+    use wasmer_clif_backend::CraneliftCompiler;
+    CraneliftCompiler::new()
+}
+
+fn gas(ctx: &mut Ctx, gas_amount: u32) {
+    use wasmer_middleware_common::metering;
+    let used = metering::get_points_used_ctx(ctx);
+    metering::set_points_used_ctx(ctx, used + u64::from(gas_amount));
+    ()
+}
+
+fn bench_metering(c: &mut Criterion) {
+    use wasmer_middleware_common::metering;
+
+    c.bench(
+        "Meter",
+        Benchmark::new("No Metering", |b| {
+            let compiler = get_compiler(0, false);
+            let wasm_binary = wat2wasm(WAT).unwrap();
+            let module = compile_with(&wasm_binary, &compiler).unwrap();
+            let import_object = imports! {};
+            let mut instance = module.instantiate(&import_object).unwrap();
+            let add_to: Func<(i32, i32), i32> = instance.func("add_to").unwrap();
+            b.iter(|| black_box(add_to.call(100, 4)))
+        })
+        .with_function("Gas Metering", |b| {
+            let compiler = get_compiler(0, false);
+            let gas_wasm_binary = wat2wasm(WAT_GAS).unwrap();
+            let gas_module = compile_with(&gas_wasm_binary, &compiler).unwrap();
+            let gas_import_object = imports! {
+                "env" => {
+                   "gas" => Func::new(gas),
+                },
+            };
+            let mut gas_instance = gas_module.instantiate(&gas_import_object).unwrap();
+            let gas_add_to: Func<(i32, i32), i32> = gas_instance.func("add_to").unwrap();
+            b.iter(|| black_box(gas_add_to.call(100, 4)))
+        })
+        .with_function("Built-in Metering", |b| {
+            let metering_compiler = get_compiler(std::u64::MAX, true);
+            let wasm_binary = wat2wasm(WAT).unwrap();
+            let metering_module = compile_with(&wasm_binary, &metering_compiler).unwrap();
+            let metering_import_object = imports! {};
+            let mut metering_instance = metering_module
+                .instantiate(&metering_import_object)
+                .unwrap();
+            metering::set_points_used(&mut metering_instance, 0u64);
+            let metering_add_to: Func<(i32, i32), i32> = metering_instance.func("add_to").unwrap();
+            b.iter(|| black_box(metering_add_to.call(100, 4)))
+        }),
+    );
+}
+
+criterion_group!(benches, bench_metering);
+criterion_main!(benches);

lib/middleware-common/src/lib.rs

@@ -1,3 +1,4 @@
 #![deny(unused_imports, unused_variables, unused_unsafe, unreachable_patterns)]
 
 pub mod call_trace;
+pub mod metering;