Merge pull request #2452 from OffchainLabs/add-logopcodes-stylustrace

Add LOG opcodes to Stylus tracing

arbos/programs/api.go

@@ -228,6 +228,9 @@ func newApiClosures(
 		return addr, res, cost, nil
 	}
 	emitLog := func(topics []common.Hash, data []byte) error {
+		if tracingInfo != nil {
+			tracingInfo.RecordEmitLog(topics, data)
+		}
 		if readOnly {
 			return vm.ErrWriteProtection
 		}

arbos/util/tracing.go

@@ -4,6 +4,7 @@
 package util
 
 import (
+	"fmt"
 	"math/big"
 
 	"github.com/ethereum/go-ethereum/common"
@@ -47,6 +48,26 @@ func NewTracingInfo(evm *vm.EVM, from, to common.Address, scenario TracingScenar
 	}
 }
 
+func (info *TracingInfo) RecordEmitLog(topics []common.Hash, data []byte) {
+	size := uint64(len(data))
+	var args []uint256.Int
+	args = append(args, *uint256.NewInt(0))    // offset: byte offset in the memory in bytes
+	args = append(args, *uint256.NewInt(size)) // size: byte size to copy (length of data)
+	for _, topic := range topics {
+		args = append(args, HashToUint256(topic)) // topic: 32-byte value. Max topics count is 4
+	}
+	memory := vm.NewMemory()
+	memory.Resize(size)
+	memory.Set(0, size, data)
+	scope := &vm.ScopeContext{
+		Memory:   memory,
+		Stack:    TracingStackFromArgs(args...),
+		Contract: info.Contract,
+	}
+	logType := fmt.Sprintf("LOG%d", len(topics))
+	info.Tracer.CaptureState(0, vm.StringToOp(logType), 0, 0, scope, []byte{}, info.Depth, nil)
+}
+
 func (info *TracingInfo) RecordStorageGet(key common.Hash) {
 	tracer := info.Tracer
 	if info.Scenario == TracingDuringEVM {

system_tests/program_test.go

@@ -19,6 +19,7 @@ import (
 	"github.com/ethereum/go-ethereum"
 	"github.com/ethereum/go-ethereum/accounts/abi/bind"
 	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/common/hexutil"
 	"github.com/ethereum/go-ethereum/core/state"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/core/vm"
@@ -739,10 +740,15 @@ func testReturnData(t *testing.T, jit bool) {
 
 func TestProgramLogs(t *testing.T) {
 	t.Parallel()
-	testLogs(t, true)
+	testLogs(t, true, false)
 }
 
-func testLogs(t *testing.T, jit bool) {
+func TestProgramLogsWithTracing(t *testing.T) {
+	t.Parallel()
+	testLogs(t, true, true)
+}
+
+func testLogs(t *testing.T, jit, tracing bool) {
 	builder, auth, cleanup := setupProgramTest(t, jit)
 	ctx := builder.ctx
 	l2info := builder.L2Info
@@ -751,6 +757,27 @@ func testLogs(t *testing.T, jit bool) {
 	logAddr := deployWasm(t, ctx, auth, l2client, rustFile("log"))
 	multiAddr := deployWasm(t, ctx, auth, l2client, rustFile("multicall"))
 
+	type traceLog struct {
+		Address common.Address `json:"address"`
+		Topics  []common.Hash  `json:"topics"`
+		Data    hexutil.Bytes  `json:"data"`
+	}
+	traceTx := func(tx *types.Transaction) []traceLog {
+		type traceLogs struct {
+			Logs []traceLog `json:"logs"`
+		}
+		var trace traceLogs
+		traceConfig := map[string]interface{}{
+			"tracer": "callTracer",
+			"tracerConfig": map[string]interface{}{
+				"withLog": true,
+			},
+		}
+		rpc := l2client.Client()
+		err := rpc.CallContext(ctx, &trace, "debug_traceTransaction", tx.Hash(), traceConfig)
+		Require(t, err)
+		return trace.Logs
+	}
 	ensure := func(tx *types.Transaction, err error) *types.Receipt {
 		t.Helper()
 		Require(t, err)
@@ -777,6 +804,20 @@ func testLogs(t *testing.T, jit bool) {
 			topics[j] = testhelpers.RandomHash()
 		}
 		data := randBytes(0, 48)
+		verifyLogTopicsAndData := func(logData []byte, logTopics []common.Hash) {
+			if !bytes.Equal(logData, data) {
+				Fatal(t, "data mismatch", logData, data)
+			}
+			if len(logTopics) != len(topics) {
+				Fatal(t, "topics mismatch", len(logTopics), len(topics))
+			}
+			for j := 0; j < i; j++ {
+				if logTopics[j] != topics[j] {
+					Fatal(t, "topic mismatch", logTopics, topics)
+				}
+			}
+		}
+
 		args := encode(topics, data)
 		tx := l2info.PrepareTxTo("Owner", &logAddr, 1e9, nil, args)
 		receipt := ensure(tx, l2client.SendTransaction(ctx, tx))
@@ -785,16 +826,14 @@ func testLogs(t *testing.T, jit bool) {
 			Fatal(t, "wrong number of logs", len(receipt.Logs))
 		}
 		log := receipt.Logs[0]
-		if !bytes.Equal(log.Data, data) {
-			Fatal(t, "data mismatch", log.Data, data)
-		}
-		if len(log.Topics) != len(topics) {
-			Fatal(t, "topics mismatch", len(log.Topics), len(topics))
-		}
-		for j := 0; j < i; j++ {
-			if log.Topics[j] != topics[j] {
-				Fatal(t, "topic mismatch", log.Topics, topics)
+		verifyLogTopicsAndData(log.Data, log.Topics)
+		if tracing {
+			logs := traceTx(tx)
+			if len(logs) != 1 {
+				Fatal(t, "wrong number of logs in trace", len(logs))
 			}
+			log := logs[0]
+			verifyLogTopicsAndData(log.Data, log.Topics)
 		}
 	}
 

system_tests/stylus_test.go

@@ -41,7 +41,7 @@ func TestProgramArbitratorReturnData(t *testing.T) {
 }
 
 func TestProgramArbitratorLogs(t *testing.T) {
-	testLogs(t, false)
+	testLogs(t, false, false)
 }
 
 func TestProgramArbitratorCreate(t *testing.T) {