Simplify LegacyVM's SUICIDE logic

Author: halfalicious

libethcore/EVMSchedule.h

@@ -83,7 +83,6 @@ struct EVMSchedule
     boost::optional<u256> blockRewardOverwrite;
 
     bool staticCallDepthLimit() const { return !eip150Mode; }
-    bool suicideChargesNewAccountGas() const { return eip150Mode; }
     bool emptinessIsNonexistence() const { return eip158Mode; }
     bool zeroValueTransferChargesNewAccountGas() const { return !eip158Mode; }
 };

libevm/LegacyVM.cpp

@@ -338,12 +338,11 @@ void LegacyVM::interpretCases()
             // Starting with EIP150, self-destructs need to pay both gas cost and account creation
             // gas cost. Starting with EIP158, 0-value self-destructs don't need to pay this account
             // creation cost.
-            if (m_schedule->zeroValueTransferChargesNewAccountGas() ||
-                m_schedule->suicideChargesNewAccountGas())
-                if (m_schedule->zeroValueTransferChargesNewAccountGas() ||
-                    m_ext->balance(m_ext->myAddress) > 0)
-                    if (m_schedule->suicideChargesNewAccountGas() && !m_ext->exists(dest))
-                        m_runGas += m_schedule->callNewAccountGas;
+            if (m_schedule->eip150Mode && (!m_schedule->eip158Mode || m_ext->balance(dest) > 0))
+            {
+                if (!m_ext->exists(dest))
+                    m_runGas += m_schedule->callNewAccountGas;
+            }
 
             updateIOGas();
             m_ext->suicide(dest);