1 files changed, 193 insertions, 0 deletions
diff --git a/ethutil/asm.go b/ethutil/asm.go
new file mode 100644
index 000000000..a547d3ac1
--- /dev/null
+++ b/ethutil/asm.go
@@ -0,0 +1,193 @@
+package ethutil
+
+import (
+	_ "fmt"
+	"math/big"
+	_ "regexp"
+)
+
+// Op codes
+var OpCodes = map[string]byte{
+	// 0x0 range - arithmetic ops
+	"STOP": 0x00,
+	"ADD":  0x01,
+	"MUL":  0x02,
+	"SUB":  0x03,
+	"DIV":  0x04,
+	"SDIV": 0x05,
+	"MOD":  0x06,
+	"SMOD": 0x07,
+	"EXP":  0x08,
+	"NEG":  0x09,
+	"LT":   0x0a,
+	"GT":   0x0b,
+	"EQ":   0x0c,
+	"NOT":  0x0d,
+
+	// 0x10 range - bit ops
+	"AND":  0x10,
+	"OR":   0x11,
+	"XOR":  0x12,
+	"BYTE": 0x13,
+
+	// 0x20 range - crypto
+	"SHA3": 0x20,
+
+	// 0x30 range - closure state
+	"ADDRESS":      0x30,
+	"BALANCE":      0x31,
+	"ORIGIN":       0x32,
+	"CALLER":       0x33,
+	"CALLVALUE":    0x34,
+	"CALLDATALOAD": 0x35,
+	"CALLDATASIZE": 0x36,
+	"GASPRICE":     0x38,
+
+	// 0x40 range - block operations
+	"PREVHASH":   0x40,
+	"COINBASE":   0x41,
+	"TIMESTAMP":  0x42,
+	"NUMBER":     0x43,
+	"DIFFICULTY": 0x44,
+	"GASLIMIT":   0x45,
+
+	// 0x50 range - 'storage' and execution
+	"PUSH": 0x50,
+
+	"PUSH20": 0x80,
+
+	"POP":     0x51,
+	"DUP":     0x52,
+	"SWAP":    0x53,
+	"MLOAD":   0x54,
+	"MSTORE":  0x55,
+	"MSTORE8": 0x56,
+	"SLOAD":   0x57,
+	"SSTORE":  0x58,
+	"JUMP":    0x59,
+	"JUMPI":   0x5a,
+	"PC":      0x5b,
+	"MSIZE":   0x5c,
+
+	// 0x60 range - closures
+	"CREATE": 0x60,
+	"CALL":   0x61,
+	"RETURN": 0x62,
+
+	// 0x70 range - other
+	"LOG":     0x70,
+	"SUICIDE": 0x7f,
+}
+
+// Is op code
+//
+// Check whether the given string matches anything in
+// the OpCode list
+func IsOpCode(s string) bool {
+	for key, _ := range OpCodes {
+		if key == s {
+			return true
+		}
+	}
+	return false
+}
+
+// Compile instruction
+//
+// Attempts to compile and parse the given instruction in "s"
+// and returns the byte sequence
+func CompileInstr(s interface{}) ([]byte, error) {
+	switch s.(type) {
+	case string:
+		str := s.(string)
+		isOp := IsOpCode(str)
+		if isOp {
+			return []byte{OpCodes[str]}, nil
+		}
+
+		num := new(big.Int)
+		_, success := num.SetString(str, 0)
+		// Assume regular bytes during compilation
+		if !success {
+			num.SetBytes([]byte(str))
+		} else {
+			// tmp fix for 32 bytes
+			n := BigToBytes(num, 256)
+			return n, nil
+		}
+
+		return num.Bytes(), nil
+	case int:
+		num := BigToBytes(big.NewInt(int64(s.(int))), 256)
+		return num, nil
+	case []byte:
+		return BigD(s.([]byte)).Bytes(), nil
+	}
+
+	return nil, nil
+}
+
+// Assemble
+//
+// Assembles the given instructions and returns EVM byte code
+func Assemble(instructions ...interface{}) (script []byte) {
+	//script = make([]string, len(instructions))
+
+	for _, val := range instructions {
+		instr, _ := CompileInstr(val)
+
+		//script[i] = string(instr)
+		script = append(script, instr...)
+	}
+
+	return
+}
+
+// Pre process script
+//
+// Take data apart and attempt to find the "init" section and
+// "main" section. `main { } init { }`
+func PreProcess(data string) (mainInput, initInput string) {
+	mainInput = getCodeSectionFor("main", data)
+	if mainInput == "" {
+		mainInput = data
+	}
+	initInput = getCodeSectionFor("init", data)
+
+	return
+}
+
+// Very, very dumb parser. Heed no attention :-)
+func getCodeSectionFor(blockMatcher, input string) string {
+	curCount := -1
+	length := len(blockMatcher)
+	matchfst := rune(blockMatcher[0])
+	var currStr string
+
+	for i, run := range input {
+		// Find init
+		if curCount == -1 && run == matchfst && input[i:i+length] == blockMatcher {
+			curCount = 0
+		} else if curCount > -1 {
+			if run == '{' {
+				curCount++
+				if curCount == 1 {
+					continue
+				}
+			} else if run == '}' {
+				curCount--
+				if curCount == 0 {
+					// we are done
+					curCount = -1
+					break
+				}
+			}
+
+			if curCount > 0 {
+				currStr += string(run)
+			}
+		}
+	}
+
+	return currStr
+}