added jump shortcut mnemonics to MU8A

README.md

@@ -163,6 +163,23 @@ specifications: here, it's `[selector] [value] [jumpaddr]` as opposed to
 `[value] [jumpaddr] [selector]`. This has been done for more convenient
 jump programming by selecting the condition as the first operand.
 
+The shortcut mnemonics for the jump operations are as follows:
+
+* `jeq` is a shortcut to `jmp 0` (direct jump if equals to zero)
+* `jgt` is a shortcut to `jmp 1` (direct jump if greater than zero)
+* `jlt` is a shortcut to `jmp 2` (direct jump if less than zero)
+* `jge` is a shortcut to `jmp 3` (direct jump if greater than or equals to zero)
+* `jle` is a shortcut to `jmp 4` (direct jump if less than or equals to zero)
+* `jne` is a shortcut to `jmp 5` (direct jump if not equals to zero)
+* `juc` is a shortcut to `jmp 6 0` (direct unconditional jump)
+* `ieq` is a shortcut to `jmp 7` (indirect jump if equals to zero)
+* `igt` is a shortcut to `jmp 8` (indirect jump if greater than zero)
+* `ilt` is a shortcut to `jmp 9` (indirect jump if less than zero)
+* `ige` is a shortcut to `jmp 10` (indirect jump if greater than or equals to zero)
+* `ile` is a shortcut to `jmp 11` (indirect jump if less than or equals to zero)
+* `ine` is a shortcut to `jmp 12` (indirect jump if not equals to zero)
+* `iuc` is a shortcut to `jmp 13 0` (indirect unconditional jump)
+
 ### Port input and output
 
 For the commands 3 and 4, mu808 supports optional non-zero port numbers, where
@@ -226,18 +243,19 @@ the MU8A assembly file to convert it into a plain text based machine code
 representation:
 
 1. Remove all comments (starting with `;` until the end of the line).
-2. Record the current line number N (not counting completely empty lines),
+2. Replace all jump shortcuts according to the above mnemonics.
+3. Record the current line number N (not counting completely empty lines),
    starting with 1.
-3. Split the line into space-delimited fields (1-based numbering as well).
-4. Check if the first field starts with `:`. If so, mark the mapping between
+4. Split the line into space-delimited fields (1-based numbering as well).
+5. Check if the first field starts with `:`. If so, mark the mapping between
    the field text and the number N, then remove the field from the set
    (so that the field 2 becomes field 1 and so on).
-5. If the field 1 is not already a number, replace the field 1 mnemonic text
+6. If the field 1 is not already a number, replace the field 1 mnemonic text
    with the numeric opcode if it can be found. If it's not a number and the
    mnemonic cannot be found, report an error and halt the process.
-6. Prepend N and the space to the current line and write the result into the
+7. Prepend N and the space to the current line and write the result into the
    target file.
-7. After the steps 1 to 6 are complete for every line, replace every label
+8. After the steps 1 to 7 are complete for every line, replace every label
    occurrence in the mapping with the corresponding number in the target file.
 
 Examples

mu808asm.py

@@ -17,13 +17,33 @@ import sys, re, struct
 mnemos = ['nop', 'jmp', 'iat', 'out', 'inp', 'set', 'cpy', 'fma',
          'sub', 'div', 'mdf', 'abs', 'sqr', 'nel', 'tri', 'rnd']
 
+# mu808 jump shortcuts
+jmp_shorts = {
+    'jeq': 'jmp 0',    # direct jump if equals to zero
+    'jgt': 'jmp 1',    # direct jump if greater than zero
+    'jlt': 'jmp 2',    # direct jump if less than zero
+    'jge': 'jmp 3',    # direct jump if greater than or equals to zero
+    'jle': 'jmp 4',    # direct jump if less than or equals to zero
+    'jne': 'jmp 5',    # direct jump if not equals to zero
+    'juc': 'jmp 6 0',  # direct unconditional jump
+    'ieq': 'jmp 7',    # indirect jump if equals to zero
+    'igt': 'jmp 8',    # indirect jump if greater than zero
+    'ilt': 'jmp 9',    # indirect jump if less than zero
+    'ige': 'jmp 10',   # indirect jump if greater than or equals to zero
+    'ile': 'jmp 11',   # indirect jump if less than or equals to zero
+    'ine': 'jmp 12',   # indirect jump if not equals to zero
+    'iuc': 'jmp 13 0'  # indirect unconditional jump
+}
+
 # converts the MU8A source code to the plaintext machine code representation
 def assemble(source):
     labels = {}
     out = ''
     lno = 0
     vreg = re.compile(r'\s+')
-    for line in source.split('\n'):
+    for shrt, meaning in jmp_shorts.items(): # replace the jump shortcuts
+        source = source.replace(shrt, meaning)
+    for line in source.split('\n'): # parse the main code
         fields = []
         line = line.split(';')[0].strip()
         if len(line) > 0: # actual line to be counted on