reworked stack

vm/stack.go

@@ -5,98 +5,53 @@ import (
 	"math/big"
 )
 
-type OpType int
+func newStack() *stack {
+	return &stack{}
+}
 
-const (
-	tNorm = iota
-	tData
-	tExtro
-	tCrypto
-)
-
-type TxCallback func(opType OpType) bool
-
-// Simple push/pop stack mechanism
-type Stack struct {
+type stack struct {
 	data []*big.Int
+	ptr  int
 }
 
-func NewStack() *Stack {
-	return &Stack{}
-}
-
-func (st *Stack) Data() []*big.Int {
-	return st.data
-}
-
-func (st *Stack) Len() int {
-	return len(st.data)
-}
-
-func (st *Stack) Pop() *big.Int {
-	str := st.data[len(st.data)-1]
-
-	copy(st.data[:len(st.data)-1], st.data[:len(st.data)-1])
-	st.data = st.data[:len(st.data)-1]
-
-	return str
-}
-
-func (st *Stack) Popn() (*big.Int, *big.Int) {
-	ints := st.data[len(st.data)-2:]
-
-	copy(st.data[:len(st.data)-2], st.data[:len(st.data)-2])
-	st.data = st.data[:len(st.data)-2]
-
-	return ints[0], ints[1]
-}
-
-func (st *Stack) Peek() *big.Int {
-	str := st.data[len(st.data)-1]
-
-	return str
-}
-
-func (st *Stack) Peekn() (*big.Int, *big.Int) {
-	ints := st.data[len(st.data)-2:]
-
-	return ints[0], ints[1]
-}
-
-func (st *Stack) Swapn(n int) (*big.Int, *big.Int) {
-	st.data[len(st.data)-n], st.data[len(st.data)-1] = st.data[len(st.data)-1], st.data[len(st.data)-n]
-
-	return st.data[len(st.data)-n], st.data[len(st.data)-1]
-}
-
-func (st *Stack) Dupn(n int) *big.Int {
-	st.Push(st.data[len(st.data)-n])
-
-	return st.Peek()
-}
-
-func (st *Stack) Push(d *big.Int) {
-	st.data = append(st.data, new(big.Int).Set(d))
-}
-
-func (st *Stack) Get(amount *big.Int) []*big.Int {
-	// offset + size <= len(data)
-	length := big.NewInt(int64(len(st.data)))
-	if amount.Cmp(length) <= 0 {
-		start := new(big.Int).Sub(length, amount)
-		return st.data[start.Int64():length.Int64()]
+func (st *stack) push(d *big.Int) {
+	if len(st.data) > st.ptr {
+		st.data[st.ptr] = d
+	} else {
+		st.data = append(st.data, d)
 	}
-
-	return nil
+	st.ptr++
 }
 
-func (st *Stack) require(n int) {
-	if st.Len() < n {
-		panic(fmt.Sprintf("stack underflow (%d <=> %d)", st.Len(), n))
+func (st *stack) pop() (ret *big.Int) {
+	st.ptr--
+	ret = st.data[st.ptr]
+	return
+}
+
+func (st *stack) len() int {
+	return st.ptr
+}
+
+func (st *stack) swap(n int) {
+	st.data[st.len()-n], st.data[st.len()-1] = st.data[st.len()-1], st.data[st.len()-n]
+}
+
+func (st *stack) dup(n int) {
+	st.push(st.data[st.len()-n])
+}
+
+func (st *stack) peek() *big.Int {
+	return st.data[st.len()-1]
+}
+
+func (st *stack) require(n int) {
+	if st.len() < n {
+		panic(fmt.Sprintf("stack underflow (%d <=> %d)", len(st.data), n))
 	}
 }
 
-func (st *Stack) Print() {
+func (st *stack) Print() {
 	fmt.Println("### stack ###")
 	if len(st.data) > 0 {
 		for i, val := range st.data {
@@ -107,72 +62,3 @@ func (st *Stack) Print() {
 	}
 	fmt.Println("#############")
 }
-
-type Memory struct {
-	store []byte
-}
-
-func NewMemory() *Memory {
-	return &Memory{nil}
-}
-
-func (m *Memory) Set(offset, size uint64, value []byte) {
-	if len(value) > 0 {
-		totSize := offset + size
-		lenSize := uint64(len(m.store) - 1)
-		if totSize > lenSize {
-			// Calculate the diff between the sizes
-			diff := totSize - lenSize
-			if diff > 0 {
-				// Create a new empty slice and append it
-				newSlice := make([]byte, diff-1)
-				// Resize slice
-				m.store = append(m.store, newSlice...)
-			}
-		}
-		copy(m.store[offset:offset+size], value)
-	}
-}
-
-func (m *Memory) Resize(size uint64) {
-	if uint64(m.Len()) < size {
-		m.store = append(m.store, make([]byte, size-uint64(m.Len()))...)
-	}
-}
-
-func (self *Memory) Get(offset, size int64) (cpy []byte) {
-	if size == 0 {
-		return nil
-	}
-
-	if len(self.store) > int(offset) {
-		cpy = make([]byte, size)
-		copy(cpy, self.store[offset:offset+size])
-
-		return
-	}
-
-	return
-}
-
-func (m *Memory) Len() int {
-	return len(m.store)
-}
-
-func (m *Memory) Data() []byte {
-	return m.store
-}
-
-func (m *Memory) Print() {
-	fmt.Printf("### mem %d bytes ###\n", len(m.store))
-	if len(m.store) > 0 {
-		addr := 0
-		for i := 0; i+32 <= len(m.store); i += 32 {
-			fmt.Printf("%03d: % x\n", addr, m.store[i:i+32])
-			addr++
-		}
-	} else {
-		fmt.Println("-- empty --")
-	}
-	fmt.Println("####################")
-}