Add tracing output for t8n

lib/evmone/tracing.cpp

@@ -68,6 +68,7 @@ class HistogramTracer : public Tracer
 
 class InstructionTracer : public Tracer
 {
+protected:
     struct Context
     {
         const uint8_t* const code;  ///< Reference to the code being executed.
@@ -149,6 +150,61 @@ class InstructionTracer : public Tracer
         m_out << std::dec;  // Set number formatting to dec, JSON does not support other forms.
     }
 };
+
+/// Standard tracer implemented to satisfy retesteth requirements
+/// Documented here: https://github.com/ethereum/tests/issues/249
+class StandardTracer : public InstructionTracer
+{
+    void on_execution_start(
+        evmc_revision /*rev*/, const evmc_message& msg, bytes_view code) noexcept override
+    {
+        m_contexts.emplace(code.data(), msg.gas);
+    }
+
+    void on_instruction_start(uint32_t pc, const intx::uint256* stack_top, int stack_height,
+        int64_t gas, const ExecutionState& state) noexcept override
+    {
+        const auto& ctx = m_contexts.top();
+
+        const auto opcode = ctx.code[pc];
+        m_out << "{";
+        m_out << R"("pc":)" << std::dec << pc;
+        m_out << R"(,"op":)" << std::dec << int{opcode};
+        m_out << R"(,"opName":")" << get_name(opcode) << '"';
+        m_out << R"(,"gas":"0x)" << std::hex << gas << '"';
+        m_out << R"("gasCost":"0x)" << std::hex << instr::gas_costs[state.rev][opcode] << '"';
+        output_stack(stack_top, stack_height);
+        m_out << R"("depth":)" << std::dec << state.msg->depth;
+        m_out << R"("refund":)" << std::dec << state.gas_refund;
+
+        // Full memory can be dumped as evmc::hex({state.memory.data(), state.memory.size()}),
+        // but this should not be done by default. Adding --tracing=+memory option would be nice.
+        m_out << R"(,"memSize":)" << std::dec << state.memory.size();
+
+        m_out << "}\n";
+    }
+
+    void on_execution_end(const evmc_result& result) noexcept override
+    {
+        const auto& ctx = m_contexts.top();
+
+        m_out << "{";
+        m_out << R"("error":)";
+        if (result.status_code == EVMC_SUCCESS)
+            m_out << R"("")";
+        else
+            m_out << '"' << result.status_code << '"';
+        m_out << R"(,"gasUsed":"0x)" << std::hex << (ctx.start_gas - result.gas_left) << '"';
+        m_out << R"(,"output":")" << evmc::hex({result.output_data, result.output_size}) << '"';
+        m_out << "}\n";
+
+        m_contexts.pop();
+    }
+
+public:
+    explicit StandardTracer(std::ostream& out) noexcept : InstructionTracer(out) {}
+};
+
 }  // namespace
 
 std::unique_ptr<Tracer> create_histogram_tracer(std::ostream& out)
@@ -160,4 +216,9 @@ std::unique_ptr<Tracer> create_instruction_tracer(std::ostream& out)
 {
     return std::make_unique<InstructionTracer>(out);
 }
+
+std::unique_ptr<Tracer> create_standard_tracer(std::ostream& out)
+{
+    return std::make_unique<StandardTracer>(out);
+}
 }  // namespace evmone

lib/evmone/tracing.hpp

@@ -65,4 +65,6 @@ EVMC_EXPORT std::unique_ptr<Tracer> create_histogram_tracer(std::ostream& out);
 
 EVMC_EXPORT std::unique_ptr<Tracer> create_instruction_tracer(std::ostream& out);
 
+EVMC_EXPORT std::unique_ptr<Tracer> create_standard_tracer(std::ostream& out);
+
 }  // namespace evmone

lib/evmone/vm.cpp

@@ -10,6 +10,7 @@
 #include "baseline.hpp"
 #include <evmone/evmone.h>
 #include <cassert>
+#include <filesystem>
 #include <iostream>
 
 namespace evmone
@@ -56,6 +57,14 @@ evmc_set_option_result set_option(evmc_vm* c_vm, char const* c_name, char const*
         vm.add_tracer(create_instruction_tracer(std::cerr));
         return EVMC_SET_OPTION_SUCCESS;
     }
+    else if (name == "stdtrace")
+    {
+        if (value == "no")
+            vm.remove_tracers();  // TODO: It removes all. Consider adding "no" value to `trace`?
+        else
+            vm.add_standard_tracer(value);
+        return EVMC_SET_OPTION_SUCCESS;
+    }
     else if (name == "histogram")
     {
         vm.add_tracer(create_histogram_tracer(std::cerr));
@@ -67,7 +76,7 @@ evmc_set_option_result set_option(evmc_vm* c_vm, char const* c_name, char const*
 }  // namespace
 
 
-inline constexpr VM::VM() noexcept
+inline VM::VM() noexcept
   : evmc_vm{
         EVMC_ABI_VERSION,
         "evmone",
@@ -79,6 +88,17 @@ inline constexpr VM::VM() noexcept
     }
 {}
 
+void VM::add_standard_tracer(std::string_view output_name) noexcept
+{
+    if (output_name == "stderr")
+        add_tracer(create_standard_tracer(std::cerr));
+    else  // File output
+    {
+        add_tracer(create_standard_tracer(
+            m_tracing_outputs.emplace_back(std::filesystem::path(output_name))));
+    }
+}
+
 }  // namespace evmone
 
 extern "C" {

lib/evmone/vm.hpp

@@ -5,6 +5,8 @@
 
 #include "tracing.hpp"
 #include <evmc/evmc.h>
+#include <fstream>
+#include <vector>
 
 #if defined(_MSC_VER) && !defined(__clang__)
 #define EVMONE_CGOTO_SUPPORTED 0
@@ -22,9 +24,10 @@ class VM : public evmc_vm
 
 private:
     std::unique_ptr<Tracer> m_first_tracer;
+    std::vector<std::ofstream> m_tracing_outputs;
 
 public:
-    inline constexpr VM() noexcept;
+    inline VM() noexcept;
 
     void add_tracer(std::unique_ptr<Tracer> tracer) noexcept
     {
@@ -35,6 +38,14 @@ class VM : public evmc_vm
         *end = std::move(tracer);
     }
 
+    void add_standard_tracer(std::string_view output_name) noexcept;
+
+    void remove_tracers() noexcept
+    {
+        m_first_tracer = nullptr;
+        m_tracing_outputs.clear();
+    }
+
     [[nodiscard]] Tracer* get_tracer() const noexcept { return m_first_tracer.get(); }
 };
 }  // namespace evmone

test/t8n/CMakeLists.txt

@@ -8,6 +8,7 @@ find_package(nlohmann_json CONFIG REQUIRED)
 add_executable(evmone-t8n)
 target_link_libraries(evmone-t8n PRIVATE evmone::statetestutils nlohmann_json::nlohmann_json)
 target_link_libraries(evmone-t8n PRIVATE evmc::evmc evmone)
+target_include_directories(evmone-t8n PRIVATE ${evmone_private_include_dir})
 target_sources(evmone-t8n PRIVATE t8n.cpp)
 
 # Provide the project version to selected source files.

test/t8n/t8n.cpp

@@ -30,6 +30,7 @@ int main(int argc, const char* argv[])
     fs::path output_body_file;
     std::optional<uint64_t> block_reward;
     uint64_t chain_id = 0;
+    bool tracing_enabled = false;
 
     try
     {
@@ -62,6 +63,8 @@ int main(int argc, const char* argv[])
                 chain_id = intx::from_string<uint64_t>(argv[i]);
             else if (arg == "--output.body" && ++i < argc)
                 output_body_file = argv[i];
+            else if (arg == "--trace")
+                tracing_enabled = true;
         }
 
         state::BlockInfo block;
@@ -106,9 +109,8 @@ int main(int argc, const char* argv[])
                     auto tx = test::from_json<state::Transaction>(j_txs[i]);
                     tx.chain_id = chain_id;
 
-                    auto res = state::transition(state, block, tx, rev, vm);
-
                     const auto computed_tx_hash = keccak256(rlp::encode(tx));
+                    const auto computed_tx_hash_str = hex0x(computed_tx_hash);
 
                     if (j_txs[i].contains("hash"))
                     {
@@ -117,15 +119,28 @@ int main(int argc, const char* argv[])
 
                         if (loaded_tx_hash_opt != computed_tx_hash)
                             throw std::logic_error("transaction hash mismatched: computed " +
-                                                   hex0x(computed_tx_hash) + ", expected " +
+                                                   computed_tx_hash_str + ", expected " +
                                                    hex0x(loaded_tx_hash_opt.value()));
                     }
 
+                    if (tracing_enabled)
+                    {
+                        // Remove old tracers
+                        vm.set_option("stdtrace", "no");
+                        auto output_filename =
+                            fs::path(output_dir / ("trace-" + std::to_string(i) + "-" +
+                                                      computed_tx_hash_str + ".jsonl"));
+                        // Add 'to file' tracer. Casting required by windows build.
+                        vm.set_option("stdtrace", (const char*)(output_filename.c_str()));
+                    }
+
+                    auto res = state::transition(state, block, tx, rev, vm);
+
                     if (holds_alternative<std::error_code>(res))
                     {
                         const auto ec = std::get<std::error_code>(res);
                         json::json j_rejected_tx;
-                        j_rejected_tx["hash"] = hex0x(computed_tx_hash);
+                        j_rejected_tx["hash"] = computed_tx_hash_str;
                         j_rejected_tx["index"] = i;
                         j_rejected_tx["error"] = ec.message();
                         j_result["rejected"].push_back(j_rejected_tx);
@@ -139,7 +154,7 @@ int main(int argc, const char* argv[])
                         txs_logs.insert(txs_logs.end(), tx_logs.begin(), tx_logs.end());
                         auto& j_receipt = j_result["receipts"][j_result["receipts"].size()];
 
-                        j_receipt["transactionHash"] = hex0x(computed_tx_hash);
+                        j_receipt["transactionHash"] = computed_tx_hash_str;
                         j_receipt["gasUsed"] = hex0x(static_cast<uint64_t>(receipt.gas_used));
                         cumulative_gas_used += receipt.gas_used;
                         j_receipt["cumulativeGasUsed"] = hex0x(cumulative_gas_used);

test/unittests/evmone_test.cpp

@@ -6,6 +6,7 @@
 #include <evmone/evmone.h>
 #include <evmone/vm.hpp>
 #include <gtest/gtest.h>
+#include <filesystem>
 
 TEST(evmone, info)
 {
@@ -53,3 +54,28 @@ TEST(evmone, set_option_cgoto)
     EXPECT_EQ(vm.set_option("cgoto", "no"), EVMC_SET_OPTION_INVALID_NAME);
 #endif
 }
+
+TEST(evmone, set_option_stdtracer)
+{
+    evmc::VM vm{evmc_create_evmone()};
+
+    EXPECT_EQ(vm.set_option("stdtrace", "stderr"), EVMC_SET_OPTION_SUCCESS);
+    const auto& evm = *static_cast<evmone::VM*>(vm.get_raw_pointer());
+    ASSERT_NE(evm.get_tracer(), nullptr);
+
+    EXPECT_EQ(vm.set_option("stdtrace", "no"), EVMC_SET_OPTION_SUCCESS);
+    ASSERT_EQ(evm.get_tracer(), nullptr);
+
+    // TODO: Find better why to create tmp file name.
+    auto trace_test_filename = "set_option_stdtracer_test_trace_file.json";
+    ASSERT_FALSE(std::filesystem::exists(trace_test_filename));
+    EXPECT_EQ(vm.set_option("stdtrace", trace_test_filename), EVMC_SET_OPTION_SUCCESS);
+    ASSERT_NE(evm.get_tracer(), nullptr);
+
+    EXPECT_EQ(vm.set_option("stdtrace", "no"), EVMC_SET_OPTION_SUCCESS);
+    ASSERT_EQ(evm.get_tracer(), nullptr);
+
+    ASSERT_TRUE(std::filesystem::exists(trace_test_filename));
+    std::filesystem::remove(trace_test_filename);
+    ASSERT_FALSE(std::filesystem::exists(trace_test_filename));
+}

test/unittests/tracing_test.cpp

@@ -124,6 +124,20 @@ TEST_F(tracing, three_tracers)
     EXPECT_EQ(trace(dup1(0)), "A0:PUSH1 B0:PUSH1 C0:PUSH1 A2:DUP1 B2:DUP1 C2:DUP1 ");
 }
 
+TEST_F(tracing, remove_tracer)
+{
+    vm.add_tracer(std::make_unique<OpcodeTracer>(*this, "A"));
+    vm.add_tracer(std::make_unique<OpcodeTracer>(*this, "B"));
+    vm.add_tracer(std::make_unique<OpcodeTracer>(*this, "C"));
+
+    EXPECT_EQ(trace(dup1(0)), "A0:PUSH1 B0:PUSH1 C0:PUSH1 A2:DUP1 B2:DUP1 C2:DUP1 ");
+
+    vm.remove_tracers();
+    vm.add_tracer(std::make_unique<OpcodeTracer>(*this, "D"));
+
+    EXPECT_EQ(trace(dup1(0)), "D0:PUSH1 D2:DUP1 ");
+}
+
 TEST_F(tracing, histogram)
 {
     vm.add_tracer(evmone::create_histogram_tracer(trace_stream));
@@ -308,3 +322,29 @@ TEST_F(tracing, trace_eof)
 {"error":null,"gas":0xf4237,"gasUsed":0x9,"output":""}
 )");
 }
+
+TEST_F(tracing, standard_tracer)
+{
+    vm.add_tracer(evmone::create_standard_tracer(trace_stream));
+
+    trace_stream << '\n';
+    EXPECT_EQ(trace(add(2, 3)), R"(
+{"pc":0,"op":96,"opName":"PUSH1","gas":"0xf4240""gasCost":"0x3","stack":[]"depth":0"refund":0,"memSize":0}
+{"pc":2,"op":96,"opName":"PUSH1","gas":"0xf423d""gasCost":"0x3","stack":["0x3"]"depth":0"refund":0,"memSize":0}
+{"pc":4,"op":1,"opName":"ADD","gas":"0xf423a""gasCost":"0x3","stack":["0x3","0x2"]"depth":0"refund":0,"memSize":0}
+{"error":"","gasUsed":"0x9","output":""}
+)");
+}
+
+TEST_F(tracing, standard_tracer_trace_undefined_instruction)
+{
+    vm.add_tracer(evmone::create_standard_tracer(trace_stream));
+
+    const auto code = bytecode{} + OP_JUMPDEST + "EF";
+    trace_stream << '\n';
+    EXPECT_EQ(trace(code), R"(
+{"pc":0,"op":91,"opName":"JUMPDEST","gas":"0xf4240""gasCost":"0x1","stack":[]"depth":0"refund":0,"memSize":0}
+{"pc":1,"op":239,"opName":"0xef","gas":"0xf423f""gasCost":"0xffff","stack":[]"depth":0"refund":0,"memSize":0}
+{"error":"undefined instruction","gasUsed":"0xf4240","output":""}
+)");
+}