readme and cleanup

4 files changed, 31 insertions, 6 deletions

diff --git a/as/as b/as/as
deleted file mode 100755
index 3c80b92..0000000
--- a/as/as
+++ /dev/null
diff --git a/as/as.go b/as/as.go
index bcc7cf8..9a2cc11 100644
--- a/as/as.go
+++ b/as/as.go
@@ -2,30 +2,44 @@ package main
 
 import (
 	"fmt"
+	"os"
 	"strings"
 	"github.com/holiman/uint256"
-
 )
 
 func Assemble(code string) []byte {
 	bytecode := make([]byte, 0)
 
 	t := strings.Fields(code)
+	push := byte(0)
 
 	for i := range t {
 		x, found := OpcodeStrings[t[i]]
 
 		if found {
-			bytecode = append(bytecode, x)
+			push = (&x).IsPush()
+			fmt.Printf("token: %s, opcode: 0x%x, push = %d\n", t[i], int(x), int(push))
+			bytecode = append(bytecode, byte(x))
 		} else {
+			if push == 0 {
+				fmt.Fprintf(os.Stderr, "unexpected token: %s\n", t[i])
+				os.Exit(1)
+			}
 			var n *uint256.Int = nil
 			if len(t[i]) > 1 && t[i][1] == 'x' {
 				n, _ = uint256.FromHex(t[i])
 			} else {
 				n, _ = uint256.FromDecimal(t[i])
 			} 
+			
+			if (t[i] == "PUSH") {
+				push = byte(n.ByteLen())
+			} 
+
+
 			b := n.Bytes32()
-			bytecode = append(bytecode, b[:]...)
+			fmt.Printf("token: NUMBER, value: %s, push = %d\n", t[i], int(push), b[32 - push:])
+			bytecode = append(bytecode, b[32-push:]...)
 		}
 	}
 	return bytecode
diff --git a/as/main.go b/as/main.go
index 95aff46..6476dc2 100644
--- a/as/main.go
+++ b/as/main.go
@@ -6,7 +6,7 @@ import (
 )
 
 func usage(arg0 string) {
-	fmt.Fprintf(os.Stderr, "usage: %s [-o file] file.easm\n", os.Args[0])
+	fmt.Fprintf(os.Stderr, "usage: %s [-o file] file.easm\n", arg0)
 	os.Exit(1)
 }
 
@@ -20,7 +20,6 @@ func main() {
 	var ain int = 0
 
 	for i := 0; i < len(os.Args); i++ {
-		fmt.Println(os.Args[i])
 		switch os.Args[i] {
 		case "-o": 
 			i = i + 1
diff --git a/as/opcodes.go b/as/opcodes.go
index 94c2e2b..be04d19 100644
--- a/as/opcodes.go
+++ b/as/opcodes.go
@@ -49,9 +49,10 @@ const (
 	PUSH30 = 0x7d
 	PUSH31 = 0x7e
 	PUSH32 = 0x7f
+	RETURN = 0xf3
 )
 
-var OpcodeStrings = map[string]byte {
+var OpcodeStrings = map[string]Opcode {
 	"STOP":    STOP,
 	"ADD":     ADD,
 	"MUL":     MUL,
@@ -66,6 +67,7 @@ var OpcodeStrings = map[string]byte {
 	"MLOAD":   MLOAD,
 	"MSTORE":  MSTORE,
 	"MSTORE8": MSTORE8,
+	"PUSH":    PUSH1,
 	"PUSH1":   PUSH1,
 	"PUSH2":   PUSH2,
 	"PUSH3":   PUSH3,
@@ -98,4 +100,14 @@ var OpcodeStrings = map[string]byte {
 	"PUSH30":   PUSH30,
 	"PUSH31":   PUSH31,
 	"PUSH32":   PUSH32,
+	"RETURN":   RETURN,
+}
+
+// returns 0 if not push, otherwise returns number of bytes
+func (o *Opcode) IsPush() byte {
+	d := *o - PUSH1 
+	if d >= 0 && d < 31 {
+		return byte(d) + 1
+	}
+	return 0
 }