Merge pull request #17982 from holiman/polish_contantinople_extcodehash

core/vm: check empty in extcodehash

Author: karalabe

core/vm/instructions.go

@@ -544,7 +544,12 @@ func opExtCodeCopy(pc *uint64, interpreter *EVMInterpreter, contract *Contract,
 // this account should be regarded as a non-existent account and zero should be returned.
 func opExtCodeHash(pc *uint64, interpreter *EVMInterpreter, contract *Contract, memory *Memory, stack *Stack) ([]byte, error) {
 	slot := stack.peek()
-	slot.SetBytes(interpreter.evm.StateDB.GetCodeHash(common.BigToAddress(slot)).Bytes())
+	address := common.BigToAddress(slot)
+	if interpreter.evm.StateDB.Empty(address) {
+		slot.SetUint64(0)
+	} else {
+		slot.SetBytes(interpreter.evm.StateDB.GetCodeHash(address).Bytes())
+	}
 	return nil, nil
 }