Complete an ovmSSTORE and ovmSLOAD roundtrip test

core/vm/instructions.go

@@ -19,7 +19,6 @@ package vm
 import (
 	"bytes"
 	"errors"
-	"fmt"
 	"math/big"
 
 	"github.com/ethereum/go-ethereum/common"
@@ -768,27 +767,21 @@ func opCall(pc *uint64, interpreter *EVMInterpreter, contract *Contract, memory
 	toAddr := common.BigToAddress(addr)
 	value = math.U256(value)
 
-	fmt.Printf("value %s\n", value)
-	fmt.Printf("inOffset %s\n", inOffset)
-	fmt.Printf("inSize %s\n", inSize)
-	fmt.Printf("retOffset %s\n", retOffset)
-	fmt.Printf("retSize %s\n", retSize)
-	fmt.Printf("address 0x%020x\n", addr)
 	// Get the arguments from the memory.
 	args := memory.GetPtr(inOffset.Int64(), inSize.Int64())
-	fmt.Printf("args 0%x\n", args)
 
 	if bytes.Equal(toAddr.Bytes(), OvmContractAddress) && bytes.Equal(args[0:4], OvmSLOADMethodId) {
-		fmt.Println("SLOAD")
+		loc := common.BytesToHash(args[4:35])
-	}
+		val := interpreter.evm.StateDB.GetState(contract.Address(), loc)
-	if bytes.Equal(toAddr.Bytes(), OvmContractAddress) && bytes.Equal(args[0:4], OvmSSTOREMethodId) {
+		stack.push(val.Big())
-		fmt.Printf("SSTORE %v %v\n", args[4:35], args[36:68])
+		return val.Bytes(), nil
+	} else if bytes.Equal(toAddr.Bytes(), OvmContractAddress) && bytes.Equal(args[0:4], OvmSSTOREMethodId) {
 		loc := common.BytesToHash(args[4:35])
 		val := common.BytesToHash(args[36:68])
 		interpreter.evm.StateDB.SetState(contract.Address(), loc, val)
-
 		interpreter.intPool.put(val.Big())
-	}
+		return nil, nil
+	} else {
 		if value.Sign() != 0 {
 			gas += params.CallStipend
 		}
@@ -805,6 +798,7 @@ func opCall(pc *uint64, interpreter *EVMInterpreter, contract *Contract, memory
 
 		interpreter.intPool.put(addr, value, inOffset, inSize, retOffset, retSize)
 		return ret, nil
+	}
 }
 
 func opCallCode(pc *uint64, interpreter *EVMInterpreter, contract *Contract, memory *Memory, stack *Stack) ([]byte, error) {

tests/ovm_test.go

@@ -1,6 +1,7 @@
 package tests
 
 import (
+	"bytes"
 	"testing"
 
 	"github.com/ethereum/go-ethereum/common"
@@ -11,7 +12,7 @@ import (
 )
 
 var KEY = common.FromHex("0102030000000000000000000000000000000000000000000000000000000000")
-var VALUE = common.FromHex("0405060000000000000000000000000000000000000000000000000000000001")
+var VALUE = common.FromHex("0405060000000000000000000000000000000000000000000000000000000000")
 
 func mstoreBytes(bytes []byte, offset int) []byte {
 	output := make([]byte, len(bytes)*5)
@@ -60,11 +61,33 @@ func TestOvm(t *testing.T) {
 			68,
 			0,
 			0)...)
+	code = append(code, mstoreBytes(vm.OvmSLOADMethodId, 0)...)
+	code = append(code, mstoreBytes(KEY, 4)...)
+	code = append(code,
+		call(
+			vm.OvmContractAddress,
+			0,
+			0,
+			36,
+			0,
+			0)...)
+	code = append(code, []byte{
+		byte(vm.PUSH1), 0,
+		byte(vm.MSTORE),
+		byte(vm.PUSH1), 32,
+		byte(vm.PUSH1), 0,
+		byte(vm.RETURN),
+	}...)
 
 	state.SetCode(address, code)
 
-	_, _, err := runtime.Call(address, nil, &runtime.Config{State: state, Debug: true})
+	returnValue, _, err := runtime.Call(address, nil, &runtime.Config{State: state, Debug: true})
 	if err != nil {
 		t.Fatal("didn't expect error", err)
 	}
+
+	if !bytes.Equal(returnValue, VALUE) {
+		t.Errorf("Expected %020x; got %020x", returnValue, VALUE)
+	}
+
 }