ZASM

Made while drunk because zombie kept giving me shitty bytecode

Kill me now

zasm.py

@@ -0,0 +1,155 @@
+class Things:
+    opcodes = {
+        'nop': 0x00,
+        'hlt': 0x01,
+        'ld': 0x04,
+        'push': 0x05,
+        'pop': 0x06,
+        'jmp': 0x07,
+        'jz': 0x08,
+        'cmp': 0x09,
+        'inc': 0x0A,
+        'dec': 0x0B,
+        'addi': 0x0C,
+        'subi': 0x0D,
+        'add': 0x0E,
+        'sub': 0x0F,
+        'muli': 0x10,
+        'divi': 0x11,
+        'mul': 0x12,
+        'div': 0x13,
+        'test': 0x16,
+        'prt': 0x17,
+
+        'je': 0x08,
+    }
+
+    registers = {
+        'ip': 0x00,
+        'sp': 0x01,
+        'flags': 0x03,
+        'a': 0x04,
+        'b': 0x05,
+        'c': 0x06,
+        'd': 0x07,
+        'r8': 0x08,
+        'r9': 0x09,
+        'r10': 0x0A,
+        'r11': 0x0B,
+        'r12': 0x0C,
+        'r13': 0x0D,
+        'r14': 0x0E,
+        'r15': 0x0F,
+        'r16': 0x10,
+    }
+
+class ZASM:
+    def __init__(self):
+        self._out = []
+        self._pc = 0
+        self._org = 0
+        self._labels = {}
+        self._to_be_resolved = {}
+
+    def emit8(self, value):
+        self._out.append(value & 0xFF)
+        self._pc += 1
+
+    def emit16(self, value):
+        self._out.append((value & 0xFF00) >> 8)
+        self._out.append(value & 0xFF)
+        self._pc += 2
+
+    def set8(self, addr, value):
+        self._out[addr - self._org] = bytes([value & 0xFF])
+
+    def set16(self, addr, value):
+        print(self._out)
+        self._out[addr - self._org] = (value & 0xFF00) >> 8
+        self._out[addr - self._org + 1] = value & 0xFF
+
+    def assemble(self, path):
+        with open(path, 'r') as f:
+            lines = f.readlines()
+
+        line_no = 0
+        for line in lines:
+            # Strip away bullshit
+            line = line.replace(',', '')
+            line = line.replace('\n', '')
+
+            # Increment line number
+            line_no += 1
+
+            # Ignore blank lines and comments
+            if line == '':
+                continue
+            if line.startswith('#'):
+                continue
+
+            # Is it a label?
+            if not line.startswith('    '):
+                if line.startswith('org'):
+                    self._pc = int(line.split(' ')[1], 16)
+                    self._org = self._pc
+                else:
+                    self._labels[line.split(':')[0]] = self._pc
+            # It is code
+            else:
+                line = line[4:]
+                chunks = line.split(' ')
+                if chunks[0] in Things.opcodes:
+                    self.emit8(Things.opcodes[chunks[0]])
+                else:
+                    print(f'Unknown opcode: {chunks[0]} at {line_no}: {line}')
+                    break
+
+                # SUUUUPER dirty hack to do indirect addressing
+                #if chunks[1].startswith('[') and chunks[1].endswith(']'):
+                #    self.set8(self._pc - 1, Things.opcodes[chunks[0]] - 2)
+                #    chunk[1] = chunk[1][1:-1]
+                if len(chunks) == 1:
+                    self.emit16(0)
+                elif chunks[1].startswith('#'):
+                    self.emit16(int(chunks[1][1:]))
+                elif chunks[1] in Things.registers:
+                    self.emit16(Things.registers[chunks[1]])
+                else:
+                    self._to_be_resolved[self._pc] = (chunks[1], line_no, line)
+                    self.emit16(0xDADA)
+                    # print(f'Unknown register or invalid immediate: {chunks[1]!r}')
+                    # break
+
+                # SUUUUPER dirty hack to do indirect addressing
+                #if chunks[2].startswith('[') and chunks[2].endswith(']'):
+                #    self.set8(self._pc - 2, Things.opcodes[chunks[0]] - 2)
+                #    chunk[2] = chunk[2][1:-1]
+                if len(chunks) <= 2:
+                    self.emit8(0)
+                elif chunks[2] in Things.registers:
+                    self.emit8(Things.registers[chunks[2]])
+                elif chunks[2].startswith('#'):
+                    self.emit8(int(chunks[2][1:]))
+                else:
+                    print(f'Invalid immediate: {chunks[2]} at {line_no}: {line}')
+                    break
+
+        for loc, (label, line_no, line) in self._to_be_resolved.items():
+            print(loc, label, line_no, line)
+            print(self._labels)
+            if label in self._labels.keys():
+                self.set16(loc, self._labels[label])
+            else:
+                print(f'Failed to resolve {label} at {line_no}: {line}')
+                break
+
+    def write(self, path):
+        with open(path, 'wb') as f:
+            f.write(bytes(self._out))
+        self._out = b''
+
+if __name__ == '__main__':
+    asm = ZASM()
+
+    asm.assemble('test.zasm')
+    asm.write('test.bin')