Implement SSTORE net gas metering in aleth-interpreter

ethereum · Sep 3, 2018 · e14077b · e14077b
1 parent fdbb63a
commit e14077b
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Showing 5 changed files with 142 additions and 23 deletions.
diff --git a/evmc b/evmc
diff --git a/libaleth-interpreter/VM.cpp b/libaleth-interpreter/VM.cpp
@@ -1356,22 +1356,19 @@ void VM::interpretCases()
             if (m_message->flags & EVMC_STATIC)
                 throwDisallowedStateChange();
 
-            static_assert(
-                VMSchedule::sstoreResetGas <= VMSchedule::sstoreSetGas, "Wrong SSTORE gas costs");
-            m_runGas = VMSchedule::sstoreResetGas;  // Charge the modification cost up front.
-            updateIOGas();
-
-            evmc_uint256be key = toEvmC(m_SP[0]);
-            evmc_uint256be value = toEvmC(m_SP[1]);
+            evmc_uint256be const key = toEvmC(m_SP[0]);
+            evmc_uint256be const value = toEvmC(m_SP[1]);
             auto status =
                 m_context->fn_table->set_storage(m_context, &m_message->destination, &key, &value);
 
             if (status == EVMC_STORAGE_ADDED)
-            {
-                // Charge additional amount for added storage item.
-                m_runGas = VMSchedule::sstoreSetGas - VMSchedule::sstoreResetGas;
-                updateIOGas();
-            }
+                m_runGas = VMSchedule::sstoreSetGas;
+            else if (status == EVMC_STORAGE_MODIFIED || status == EVMC_STORAGE_DELETED)
+                m_runGas = VMSchedule::sstoreResetGas;
+            else
+                m_runGas = VMSchedule::sstoreUnchangedGas;
+
+            updateIOGas();
         }
         NEXT
 

diff --git a/libaleth-interpreter/VM.h b/libaleth-interpreter/VM.h
@@ -46,6 +46,7 @@ struct VMSchedule
     static constexpr int64_t sloadGas = 50;
     static constexpr int64_t sstoreSetGas = 20000;
     static constexpr int64_t sstoreResetGas = 5000;
+    static constexpr int64_t sstoreUnchangedGas = 200;
     static constexpr int64_t jumpdestGas = 1;
     static constexpr int64_t logGas = 375;
     static constexpr int64_t logDataGas = 8;

diff --git a/libevm/ExtVMFace.cpp b/libevm/ExtVMFace.cpp
@@ -58,23 +58,49 @@ evmc_storage_status setStorage(evmc_context* _context, evmc_address const* _addr
     (void)_addr;
     auto& env = static_cast<ExtVMFace&>(*_context);
     assert(fromEvmC(*_addr) == env.myAddress);
-    u256 index = fromEvmC(*_key);
-    u256 value = fromEvmC(*_value);
-    u256 oldValue = env.store(index);
+    u256 const index = fromEvmC(*_key);
+    u256 const newValue = fromEvmC(*_value);
+    u256 const currentValue = env.store(index);
 
-    if (value == oldValue)
+    if (newValue == currentValue)
         return EVMC_STORAGE_UNCHANGED;
 
+    EVMSchedule const& schedule = env.evmSchedule();
     auto status = EVMC_STORAGE_MODIFIED;
-    if (oldValue == 0)
-        status = EVMC_STORAGE_ADDED;
-    else if (value == 0)
+    u256 const originalValue = env.originalStorageValue(index);
+    if (originalValue == currentValue || !schedule.eip1283Mode)
     {
-        status = EVMC_STORAGE_DELETED;
-        env.sub.refunds += env.evmSchedule().sstoreRefundGas;
+        if (currentValue == 0)
+            status = EVMC_STORAGE_ADDED;
+        else if (newValue == 0)
+        {
+            status = EVMC_STORAGE_DELETED;
+            env.sub.refunds += schedule.sstoreRefundGas;
+        }
+    }
+    else
+    {
+        status = EVMC_STORAGE_MODIFIED_DIRTY;
+        if (originalValue == 0)
+        {
+            if (currentValue == 0)
+            {
+                assert(env.sub.refunds >= schedule.sstoreRefundGas);
+                env.sub.refunds -= schedule.sstoreRefundGas;
+            }
+            else
+                env.sub.refunds += schedule.sstoreRefundGas;
+        }
+        if (originalValue == newValue)
+        {
+            if (originalValue == 0)
+                env.sub.refunds += schedule.sstoreRefundGas + schedule.sstoreRefundNonzeroGas;
+            else
+                env.sub.refunds += schedule.sstoreRefundNonzeroGas;
+        }
     }
 
-    env.setStore(index, value);  // Interface uses native endianness
+    env.setStore(index, newValue);  // Interface uses native endianness
 
     return status;
 }

diff --git a/test/unittests/libevm/VMTest.cpp b/test/unittests/libevm/VMTest.cpp
@@ -403,6 +403,12 @@ class LegacyVMSstoreTestFixture : public SstoreTestFixture
     LegacyVMSstoreTestFixture() : SstoreTestFixture{new LegacyVM} {}
 };
 
+class AlethInterpreterSstoreTestFixture : public SstoreTestFixture
+{
+public:
+    AlethInterpreterSstoreTestFixture() : SstoreTestFixture{new EVMC{evmc_create_interpreter()}} {}
+};
+
 }  // namespace
 
 BOOST_FIXTURE_TEST_SUITE(LegacyVMSuite, TestOutputHelperFixture)
@@ -638,4 +644,93 @@ BOOST_AUTO_TEST_CASE(AlethInterpreterExtCodeHashIgnoresHigh12Bytes)
 
 BOOST_AUTO_TEST_SUITE_END()
 
+BOOST_FIXTURE_TEST_SUITE(AlethInterpreterSstoreSuite, AlethInterpreterSstoreTestFixture)
+
+BOOST_AUTO_TEST_CASE(AlethInterpreterSstoreEip1283Case1)
+{
+    testEip1283Case1();
+}
+
+BOOST_AUTO_TEST_CASE(AlethInterpreterSstoreEip1283Case2)
+{
+    testEip1283Case2();
+}
+
+BOOST_AUTO_TEST_CASE(AlethInterpreterSstoreEip1283Case3)
+{
+    testEip1283Case3();
+}
+
+BOOST_AUTO_TEST_CASE(AlethInterpreterSstoreEip1283Case4)
+{
+    testEip1283Case4();
+}
+
+BOOST_AUTO_TEST_CASE(AlethInterpreterSstoreEip1283Case5)
+{
+    testEip1283Case5();
+}
+
+BOOST_AUTO_TEST_CASE(AlethInterpreterSstoreEip1283Case6)
+{
+    testEip1283Case6();
+}
+
+BOOST_AUTO_TEST_CASE(AlethInterpreterSstoreEip1283Case7)
+{
+    testEip1283Case7();
+}
+
+BOOST_AUTO_TEST_CASE(AlethInterpreterSstoreEip1283Case8)
+{
+    testEip1283Case8();
+}
+
+BOOST_AUTO_TEST_CASE(AlethInterpreterSstoreEip1283Case9)
+{
+    testEip1283Case9();
+}
+
+BOOST_AUTO_TEST_CASE(AlethInterpreterSstoreEip1283Case10)
+{
+    testEip1283Case10();
+}
+
+BOOST_AUTO_TEST_CASE(AlethInterpreterSstoreEip1283Case11)
+{
+    testEip1283Case11();
+}
+
+BOOST_AUTO_TEST_CASE(AlethInterpreterSstoreEip1283Case12)
+{
+    testEip1283Case12();
+}
+
+BOOST_AUTO_TEST_CASE(AlethInterpreterSstoreEip1283Case13)
+{
+    testEip1283Case13();
+}
+
+BOOST_AUTO_TEST_CASE(AlethInterpreterSstoreEip1283Case14)
+{
+    testEip1283Case14();
+}
+
+BOOST_AUTO_TEST_CASE(AlethInterpreterSstoreEip1283Case15)
+{
+    testEip1283Case15();
+}
+
+BOOST_AUTO_TEST_CASE(AlethInterpreterSstoreEip1283Case16)
+{
+    testEip1283Case16();
+}
+
+BOOST_AUTO_TEST_CASE(AlethInterpreterSstoreEip1283Case17)
+{
+    testEip1283Case17();
+}
+
+BOOST_AUTO_TEST_SUITE_END()
+
 BOOST_AUTO_TEST_SUITE_END()