Initial commit

.gitignore

@@ -0,0 +1 @@
+bird-asm

go.mod

@@ -0,0 +1,3 @@
+module tildegit.org/sloum/bird-asm
+
+go 1.21.5

helpers.go

@@ -0,0 +1,44 @@
+package main
+
+import (
+  "flag"
+  "fmt"
+  "os"
+)
+
+func fileExists(p string) (bool, error) {
+  _, err := os.Stat(p)
+  if err == nil { return true, nil }
+  if os.IsNotExist(err) { return false, nil }
+  return false, err
+}
+
+func setIn() {
+  args := flag.Args()
+  if len(args) == 0 {
+    fmt.Fprintf(os.Stderr, "no input file\n")
+    os.Exit(1)
+  } else if len(args) > 1 {
+    fmt.Fprintf(os.Stderr, "too many input files (%d), needed 1\n", len(args))
+    os.Exit(2)
+  }
+  in = args[0]
+  exists, err := fileExists(in)
+  if err != nil {
+    fmt.Fprintf(os.Stderr, "could not open file\n\t%s", err.Error())
+    os.Exit(3)
+  } else if !exists {
+    fmt.Fprintf(os.Stderr, "%q does not exist\n", in)
+    os.Exit(4)
+  }
+}
+
+func setOut(o string) {
+  if o == "" {
+    out = "out.rom"
+  } else {
+    out = o
+  }
+}
+
+

main.go

@@ -0,0 +1,42 @@
+package main
+
+import (
+  "flag"
+  "fmt"
+)
+
+var (
+  version string = "0.01"
+  in  string
+  out string
+  longMask byte = 1 << 7
+  returnMask byte = 1 << 6
+  verbose bool
+  dryRun bool
+  ops = map[string]uint8{
+    "NOP": 0x00, "SET": 0x01, "GET": 0x02, "SEI": 0x03, "GEI": 0x04,
+    "PSH": 0x07, "POP": 0x08, "OVR": 0x09, "SWP": 0x0A, "ROT": 0x0B, "DUP": 0x0C, "SSW": 0x0D,
+    "ADD": 0x0E, "SUB": 0x0F, "MUL": 0x10, "DIV": 0x11, "INC": 0x12, "DEC": 0x13,
+    "AND": 0x15, "BOR": 0x16, "XOR": 0x17, "SHR": 0x18, "SHL": 0x19,
+    "JMP": 0x1C, "CAL": 0x1D, "JCD": 0x1E, "RET": 0x1F,
+    "GCH": 0x23, "GST": 0x24, "PCH": 0x25, "PST": 0x26, "HLT": 0x27, "PHX": 0x28,
+    "GRT": 0x2A, "LST": 0x2B, "GTE": 0x2C, "LTE": 0x2D, "EQL": 0x2E,
+  }
+)
+
+
+func main() {
+  flag.BoolVar(&dryRun, "dry", false, "Does a dry run (doesnot produce output file, but shows errors)")
+  flag.BoolVar(&verbose, "v", false, "Run in verbose mode")
+  ver := flag.Bool("version", false, "Print version information and exit")
+  outFile := flag.String("o", "", "Output file path")
+  flag.Parse()
+
+  if *ver {
+    fmt.Printf("bird-asm, version %s\n", version)
+    return
+  }
+
+  setIn()
+  setOut(*outFile)
+}

types.go

@@ -0,0 +1,104 @@
+package main
+
+import (
+  "fmt"
+  "os"
+  "regexp"
+)
+
+type label struct {
+  ref        uint16
+  count      uint16
+  parent     string
+  isSublabel bool
+}
+
+func (l *label) Inc() {
+  l.count++
+}
+
+type prog struct {
+  labels       map[string]label
+  sublabels    map[string]label
+  macros       map[string]string
+  source       string
+  mp           uint16
+  cp           uint16
+  unknownWords []string
+}
+
+func (p *prog) Compile() {
+  // 1. Strip comments from source file
+  p.stripComments()
+
+  // 2. Expand macros
+  p.expandMacros()
+
+}
+
+func (p *prog) stripComments() {
+  if verbose {
+    fmt.Fprint(os.Stderr, "Stripping comments\n")
+  }
+  slc := regexp.MustCompile(`\/\/.*`)
+  mlc := regexp.MustCompile(`(?s)\/\*.*\*\/`)
+  p.source = slc.ReplaceAllString(p.source, "")
+  p.source = mlc.ReplaceAllString(p.source, "")
+}
+
+func (p *prog) expandMacros() {
+  if verbose {
+    fmt.Fprint(os.Stderr, "+ Expanding macros\n")
+  }
+  // Found all macro declarations
+  re := regexp.MustCompile(`%(\w+)\s+([^;]*)\s+\;`)
+  macrosFound := re.FindAllStringSubmatch(p.source, -1)
+
+  // If there were none, return
+  if macrosFound == nil {
+    if verbose {
+      fmt.Fprint(os.Stderr, "\t└ No macros were found\n")
+    }
+    return
+  }
+
+  // Load the macros into our map
+  for i := range macrosFound {
+    p.macros[macrosFound[i][1]] = macrosFound[i][2]
+  }
+
+  // Remove the declarations
+  p.source = re.ReplaceAllString(p.source, "")
+
+  var twice bool
+  Twice:
+  // Expand the macros in the raw source
+  for k, v := range p.macros {
+    reM := regexp.MustCompile(`(?m)(\s|^)(?:`+k+`)(\s|$)`)
+    p.source = reM.ReplaceAllString(p.source, `${1}`+v+`${2}`)
+  }
+  if !twice {
+    twice = true
+    goto Twice
+  }
+  if verbose {
+    fmt.Fprintf(os.Stderr, "\t└ %d macros declarations were found and references were expanded\n", len(p.macros))
+  }
+}
+
+
+/* 1. Strip comments (using regex for dev speed at the moment)
+ * 2. Do a pass for expanding macros
+ * 3. Do a pass for finding labels
+ * 4.
+ *
+ * :Label1     (refers to program counter)
+ *   @var1     (var is a pointer to memory)
+ *     +subvar (creates a subvar at current mem pointer)
+ *     $2      (pads the mem pointer to create sizes of vars)
+ * %macro1 #2c pch .
+ * Err should be thrown if an attempt to jump tp a var/subvar
+ * is made.
+ */
+
+