Move precompiles' stubs from JSON to C++ (#853)

Create individual stubs for precompiles with missing implementation.
They can be enabled selectively and by default.

Remove cache layer and JSON stubs.

Author: chfast

README.md

@@ -91,14 +91,12 @@ To build the evmone EVMC module (shared library), test, and benchmark:
 
 ### Precompiles
 
-Ethereum Precompiled Contracts (_precompiles_ for short) are not directly supported by evmone.
+Ethereum Precompiled Contracts (_precompiles_ for short) are only partly supported by evmone.
 
 However, there are options to enable limited precompiles support for testing.
 
-1. The [test/state/precompiles_stub.json](./test/state/precompiles_stub.json) contains
-   precompiles execution results for inputs commonly used in tests.
-   You can use the precompiles STUB by setting the environment variable
-   `EVMONE_PRECOMPILES_STUB=./test/state/precompiles_stub.json`.
+1. For precompiles with missing implementation stubs are enabled by default.
+   They will correctly respond to known inputs.
 2. The CMake option `EVMONE_PRECOMPILES_SILKPRE=1` enables building of
    the [silkpre] third party library with the implementation of the precompiles.
    This library also requires [GMP] (e.g. libgmp-dev) library for building and execution.

circle.yml

@@ -410,13 +410,11 @@ jobs:
           name: "Execution spec tests (blockchain_tests)"
           working_directory: ~/build
           command: >
-            EVMONE_PRECOMPILES_STUB=~/project/test/state/precompiles_stub.json 
             bin/evmone-blockchaintest ~/spec-tests/fixtures/blockchain_tests
       - run:
           name: "Execution spec tests (state_tests)"
           working_directory: ~/build
           command: >
-            EVMONE_PRECOMPILES_STUB=~/project/test/state/precompiles_stub.json 
             bin/evmone-statetest ~/spec-tests/fixtures/state_tests
 
       - download_execution_tests:
@@ -427,31 +425,27 @@ jobs:
           name: "State tests"
           working_directory: ~/build
           command: >
-            EVMONE_PRECOMPILES_STUB=~/project/test/state/precompiles_stub.json 
             bin/evmone-statetest 
             ~/tests/GeneralStateTests 
             ~/tests/LegacyTests/Constantinople/GeneralStateTests
       - run:
           name: "Blockchain tests (GeneralStateTests)"
           working_directory: ~/build
           command: >
-            EVMONE_PRECOMPILES_STUB=~/project/test/state/precompiles_stub.json 
             bin/evmone-blockchaintest
             --gtest_filter='*:-VMTests/vmPerformance.*:*.*Call50000_sha256:*.CALLBlake2f_MaxRounds'
             ~/tests/BlockchainTests/GeneralStateTests
       - run:
           name: "Blockchain tests (ValidBlocks)"
           working_directory: ~/build
           command: >
-            EVMONE_PRECOMPILES_STUB=~/project/test/state/precompiles_stub.json 
             bin/evmone-blockchaintest
             --gtest_filter='*:-bcMultiChainTest.*:bcTotalDifficultyTest.*:bcForkStressTest.ForkStressTest:bcGasPricerTest.RPC_API_Test:bcValidBlockTest.SimpleTx3LowS'
             ~/tests/BlockchainTests/ValidBlocks
       - run:
           name: "Blockchain tests (EIPs)"
           working_directory: ~/build
           command: >
-            EVMONE_PRECOMPILES_STUB=~/project/test/state/precompiles_stub.json 
             bin/evmone-blockchaintest
             --gtest_filter='-*StateTests/stEOF/*.*'
             ~/tests/EIPTests/BlockchainTests/

test/state/CMakeLists.txt

@@ -24,9 +24,9 @@ target_sources(
     mpt_hash.cpp
     precompiles.hpp
     precompiles.cpp
-    precompiles_cache.hpp
-    precompiles_cache.cpp
     precompiles_internal.hpp
+    precompiles_stubs.hpp
+    precompiles_stubs.cpp
     rlp.hpp
     state.hpp
     state.cpp

test/state/precompiles.cpp

@@ -3,25 +3,26 @@
 // SPDX-License-Identifier: Apache-2.0
 
 #include "precompiles.hpp"
-#include "precompiles_cache.hpp"
 #include "precompiles_internal.hpp"
+#include "precompiles_stubs.hpp"
 #include <evmone_precompiles/blake2b.hpp>
 #include <evmone_precompiles/bn254.hpp>
 #include <evmone_precompiles/ripemd160.hpp>
 #include <evmone_precompiles/secp256k1.hpp>
 #include <intx/intx.hpp>
+#include <array>
 #include <bit>
 #include <cassert>
-#include <iostream>
 #include <limits>
-#include <unordered_map>
 
 #ifdef EVMONE_PRECOMPILES_SILKPRE
 #include "precompiles_silkpre.hpp"
 #endif
 
 namespace evmone::state
 {
+using evmc::bytes;
+using evmc::bytes_view;
 using namespace evmc::literals;
 
 namespace
@@ -292,26 +293,19 @@ struct PrecompileTraits
     decltype(identity_execute)* execute = nullptr;
 };
 
-template <PrecompileId Id>
-ExecutionResult dummy_execute(const uint8_t*, size_t, uint8_t*, size_t) noexcept
-{
-    std::cerr << "Precompile " << static_cast<int>(Id) << " not implemented!\n";
-    return ExecutionResult{EVMC_INTERNAL_ERROR, 0};
-}
-
 inline constexpr auto traits = []() noexcept {
     std::array<PrecompileTraits, NumPrecompiles> tbl{{
         {},  // undefined for 0
         {ecrecover_analyze, ecrecover_execute},
-        {sha256_analyze, dummy_execute<PrecompileId::sha256>},
+        {sha256_analyze, sha256_stub},
         {ripemd160_analyze, ripemd160_execute},
         {identity_analyze, identity_execute},
-        {expmod_analyze, dummy_execute<PrecompileId::expmod>},
+        {expmod_analyze, expmod_stub},
         {ecadd_analyze, ecadd_execute},
         {ecmul_analyze, ecmul_execute},
-        {ecpairing_analyze, dummy_execute<PrecompileId::ecpairing>},
+        {ecpairing_analyze, ecpairing_stub},
         {blake2bf_analyze, blake2bf_execute},
-        {point_evaluation_analyze, dummy_execute<PrecompileId::point_evaluation>},
+        {point_evaluation_analyze, point_evaluation_stub},
     }};
 #ifdef EVMONE_PRECOMPILES_SILKPRE
     // tbl[static_cast<size_t>(PrecompileId::ecrecover)].execute = silkpre_ecrecover_execute;
@@ -363,10 +357,6 @@ evmc::Result call_precompile(evmc_revision rev, const evmc_message& msg) noexcep
     if (gas_left < 0)
         return evmc::Result{EVMC_OUT_OF_GAS};
 
-    static Cache cache;
-    if (auto r = cache.find(static_cast<PrecompileId>(id), input, gas_left); r.has_value())
-        return std::move(*r);
-
     // Buffer for the precompile's output.
     // Big enough to handle all "expmod" tests, but in case does not match the size requirement
     // from analysis, the result will likely be incorrect.
@@ -380,8 +370,6 @@ evmc::Result call_precompile(evmc_revision rev, const evmc_message& msg) noexcep
     evmc::Result result{
         status_code, status_code == EVMC_SUCCESS ? gas_left : 0, 0, output_buf, output_size};
 
-    cache.insert(static_cast<PrecompileId>(id), input, result);
-
     return result;
 }
 }  // namespace evmone::state