1 files changed, 50 insertions, 12 deletions

diff --git a/asm.myr b/asm.myr
index 800a6ef..dda4eed 100644
--- a/asm.myr
+++ b/asm.myr
@@ -36,11 +36,30 @@ const readline = {line
     ;;
 }
 
-const parsehex = {s
+type literal = union
+    `Number int
+    `Register int
+    `Label byte[:]
+    `Invalid
+;;
+
+const getnum = {s
+    -> std.intparsebase((s[1:] : byte[:]), 16)
+}
+
+const parselit = {s
     if s[0] == ('#' : byte)
-        -> std.intparsebase((s[1:] : byte[:]), 16)
+        match getnum(s)
+        |`std.Some(n): -> `Number(n)
+        |`std.None: -> `Invalid
+        ;;
+    elif s[0] == ('v' : byte)
+        match getnum(s)
+        |`std.Some(n): -> `Register(n)
+        |`std.None: -> `Invalid
+        ;;
     else
-        -> `std.None
+        -> `Label(s)
     ;;
 }
 
@@ -61,19 +80,27 @@ const emitinstr = {p
         if p.len < 2
             -> `std.Err("SYS missing subroutine address")
         ;;
-        match parsehex(p[1])
-        | `std.Some(n): b = `std.Some([0x00 | (n & 0x0f00), (n & 0xff)])
-        | `std.None: b = `std.Some([0x20, 0x00])
-            mark = `std.Some(strdup(p[1]))
+        match parselit(p[1])
+        | `Number(n): b = `std.Some([0x00 | (n & 0x0f00), (n & 0xff)])
+        | `Label(l): b = `std.Some([0x20, 0x00])
+            mark = `std.Some(strdup(l))
+        | `Register(_):
+            -> `std.Err("SYS called with register instruction")
+        | `Invalid:
+            -> `std.Err(std.fmt("invalid literal {}", p[1]))
         ;;
     | "CALL":
         if p.len < 2
             -> `std.Err("CALL missing subroutine address")
         ;;
-        match parsehex(p[1])
-        | `std.Some(n): b = `std.Some([0x20 | (n & 0x0f00), (n & 0xff)])
-        | `std.None: b = `std.Some([0x20, 0x00])
-            mark = `std.Some(strdup(p[1]))
+        match parselit(p[1])
+        | `Number(n): b = `std.Some([0x00 | (n & 0x0f00), (n & 0xff)])
+        | `Label(l): b = `std.Some([0x20, 0x00])
+            mark = `std.Some(strdup(l))
+        | `Register(_):
+            -> `std.Err("CALL called with register instruction")
+        | `Invalid:
+            -> `std.Err(std.fmt("invalid literal {}", p[1]))
         ;;
     | _:
         -> `std.Err("unrecognized instruction")
@@ -91,6 +118,17 @@ const die_rewrite = {l, lc
     std.die(std.fmt(s, l, lc))
 }
 
+
+/* convert `arr` to a byte[:] slice */
+const itob = {arr
+    var i
+    var ret = std.slalloc(arr.len)
+    for i = 0; i < arr.len; i++;
+        ret[i] = ((arr[i] & 0xff) : byte)
+    ;;
+    -> ret
+}
+
 const main = {
     var fd = bio.mkfile(std.In, bio.Rd)
     var src = bio.byline(fd)
@@ -140,7 +178,7 @@ const main = {
         ;;
     ;;
 
-    std.write(std.Out, buf)
+    std.write(std.Out, itob(buf))
 
     bio.free(fd)
 }