core/vm, cmd/evm: Add ability for 'evm' binary to report gas used

cmd/evm/runner.go

@@ -137,11 +137,11 @@ func runCmd(ctx *cli.Context) error {
 		}
 		code = common.Hex2Bytes(string(bytes.TrimRight(hexcode, "\n")))
 	}
-
+	initialGas := ctx.GlobalUint64(GasFlag.Name)
 	runtimeConfig := runtime.Config{
 		Origin:   sender,
 		State:    statedb,
-		GasLimit: ctx.GlobalUint64(GasFlag.Name),
+		GasLimit: initialGas,
 		GasPrice: utils.GlobalBig(ctx, PriceFlag.Name),
 		Value:    utils.GlobalBig(ctx, ValueFlag.Name),
 		EVMConfig: vm.Config{
@@ -168,14 +168,15 @@ func runCmd(ctx *cli.Context) error {
 		runtimeConfig.ChainConfig = chainConfig
 	}
 	tstart := time.Now()
+	var leftOverGas uint64
 	if ctx.GlobalBool(CreateFlag.Name) {
 		input := append(code, common.Hex2Bytes(ctx.GlobalString(InputFlag.Name))...)
-		ret, _, err = runtime.Create(input, &runtimeConfig)
+		ret, _, leftOverGas, err = runtime.Create(input, &runtimeConfig)
 	} else {
 		receiver := common.StringToAddress("receiver")
 		statedb.SetCode(receiver, code)
 
-		ret, err = runtime.Call(receiver, common.Hex2Bytes(ctx.GlobalString(InputFlag.Name)), &runtimeConfig)
+		ret, leftOverGas, err = runtime.Call(receiver, common.Hex2Bytes(ctx.GlobalString(InputFlag.Name)), &runtimeConfig)
 	}
 	execTime := time.Since(tstart)
 
@@ -214,11 +215,12 @@ heap objects:       %d
 allocations:        %d
 total allocations:  %d
 GC calls:           %d
+Gas used:           %d
 
-`, execTime, mem.HeapObjects, mem.Alloc, mem.TotalAlloc, mem.NumGC)
+`, execTime, mem.HeapObjects, mem.Alloc, mem.TotalAlloc, mem.NumGC, initialGas-leftOverGas)
 	}
 	if tracer != nil {
-		tracer.CaptureEnd(ret, 0, execTime)
+		tracer.CaptureEnd(ret, initialGas-leftOverGas, execTime)
 	} else {
 		fmt.Printf("0x%x\n", ret)
 	}

core/vm/runtime/runtime.go

@@ -125,7 +125,7 @@ func Execute(code, input []byte, cfg *Config) ([]byte, *state.StateDB, error) {
 }
 
 // Create executes the code using the EVM create method
-func Create(input []byte, cfg *Config) ([]byte, common.Address, error) {
+func Create(input []byte, cfg *Config) ([]byte, common.Address, uint64, error) {
 	if cfg == nil {
 		cfg = new(Config)
 	}
@@ -141,13 +141,13 @@ func Create(input []byte, cfg *Config) ([]byte, common.Address, error) {
 	)
 
 	// Call the code with the given configuration.
-	code, address, _, err := vmenv.Create(
+	code, address, leftOverGas, err := vmenv.Create(
 		sender,
 		input,
 		cfg.GasLimit,
 		cfg.Value,
 	)
-	return code, address, err
+	return code, address, leftOverGas, err
 }
 
 // Call executes the code given by the contract's address. It will return the
@@ -155,14 +155,14 @@ func Create(input []byte, cfg *Config) ([]byte, common.Address, error) {
 //
 // Call, unlike Execute, requires a config and also requires the State field to
 // be set.
-func Call(address common.Address, input []byte, cfg *Config) ([]byte, error) {
+func Call(address common.Address, input []byte, cfg *Config) ([]byte, uint64, error) {
 	setDefaults(cfg)
 
 	vmenv := NewEnv(cfg, cfg.State)
 
 	sender := cfg.State.GetOrNewStateObject(cfg.Origin)
 	// Call the code with the given configuration.
-	ret, _, err := vmenv.Call(
+	ret, leftOverGas, err := vmenv.Call(
 		sender,
 		address,
 		input,
@@ -170,5 +170,5 @@ func Call(address common.Address, input []byte, cfg *Config) ([]byte, error) {
 		cfg.Value,
 	)
 
-	return ret, err
+	return ret, leftOverGas, err
 }

core/vm/runtime/runtime_test.go

@@ -106,7 +106,7 @@ func TestCall(t *testing.T) {
 		byte(vm.RETURN),
 	})
 
-	ret, err := Call(address, nil, &Config{State: state})
+	ret, _, err := Call(address, nil, &Config{State: state})
 	if err != nil {
 		t.Fatal("didn't expect error", err)
 	}