Add function to print registers

Author: coderick14

Memory/DataMemory.go

@@ -1,24 +1,78 @@
 package memory
 
-import "sync"
+import (
+	tablewriter "github.com/olekukonko/tablewriter"
+	color "github.com/fatih/color"
+	"os"
+	"sync"
+	"strconv"
+)
 
 type DataMemory struct {
 	sync.RWMutex
 	Memory []int32
 }
 
-var registers [32]int64
+var registers, buffer [32]int64
 
 var flagNegative, flagZero, flagOverflow, flagCarry bool
 
 /*
  * method to initiate register values
  */
 
- func InitRegisters() {
- 	registers[XZR] = 0
- 	registers[SP] = MEMORY_SIZE * 4 
- }
+func InitRegisters() {
+	registers[XZR] = 0
+	registers[SP] = MEMORY_SIZE * 4
+}
+
+/*
+ * function to store register values in a buffer
+ */
+
+func SaveRegisters() {
+	var i int
+	for i = 0; i < 32; i++ {
+		buffer[i] = registers[i]
+	}
+}
+
+/*
+ * function to show register values
+ */
+
+func ShowRegisters(showAll bool) {
+	var i int
+	var registerNum, prevRegisterVal, newRegisterVal string
+	table := tablewriter.NewWriter(os.Stdout)
+	if showAll == true {
+		table.SetHeader([]string{"Register", "Value"})
+
+		for i = 0; i < 32; i++ {
+			registerNum = strconv.Itoa(i)
+			newRegisterVal = strconv.FormatInt(getRegisterValue(uint(i)), 10)
+			if getRegisterValue(uint(i)) != buffer[i] {	
+				table.Append([]string{color.CyanString("R"+registerNum), color.CyanString(newRegisterVal)})
+			} else {
+				table.Append([]string{"R"+registerNum, newRegisterVal})
+			}
+		}
+	} else {
+		table.SetHeader([]string{"Register", "Previous Value", "New Value"})
+
+		for i = 0; i < 32; i++ {
+			if getRegisterValue(uint(i)) != buffer[i] {
+				registerNum = strconv.Itoa(i)
+				prevRegisterVal = strconv.FormatInt(buffer[i], 10)
+				newRegisterVal = strconv.FormatInt(getRegisterValue(uint(i)), 10)
+				table.Append([]string{color.CyanString("R"+registerNum), color.RedString(prevRegisterVal), color.GreenString(newRegisterVal)})
+			}
+		}
+	} 
+	
+
+	table.Render()
+}
 
 /*
  * Method to read data from memory

arm.go

@@ -15,14 +15,18 @@ var helpString = `ARMed version 1.0
 Author : https://github.com/coderick14
 
 ARMed is a very basic emulator of the 64-bit LEGv8 architecture written in Golang
-USAGE : ARMed [--help] SOURCE_FILE
+USAGE : ARMed [--all] SOURCE_FILE
+
+The --all flag will show all register values after an instruction, with updated ones in color.
+In absence of this flag, it will show only updated registers.
 
 Found a bug? Feel free to raise an issue on https://github.com/coderick14/ARMed
 Contributions welcome :)`
 
 func main() {
 	var err error
 	helpPtr := flag.Bool("help", false, "Display help")
+	allPtr := flag.Bool("all", false, "Display all registers")
 
 	flag.Parse()
 
@@ -63,11 +67,13 @@ func main() {
 	Memory.InitRegisters()
 
 	for _, _ = range Memory.InstructionMem.Instructions {
+		Memory.SaveRegisters()
 		err = Memory.InstructionMem.ValidateAndExecuteInstruction()
 		if err != nil {
 			fmt.Println(err)
 			return
 		}
+		Memory.ShowRegisters(*allPtr)
 	}
 
 }