Added function to simplify branch-jump combos. Not function properly yet.

src/optimizer.py

@@ -10,9 +10,38 @@ def empty_shift(statement):
     stype, name, args = statement
     return stype == 'command' and name in shift_types and \
         args['args'][0] == args['args'][1] and args['args'][2] == 0
+        
+def optimize_branch_jump_label(statements):
+    '''Optimize jumps after branches.'''
+    out_statements = []
+    
+    for i in xrange(len(statements)):
+        if i + 3 > len(statements):
+            out_statements.append(statements[i])
+            continue
+        
+        stype, name, args = statements[i]
+        stype2, name2, args2 = statements[i + 1]
+        stype3, name3, args3 = statements[i + 2]
+        
+        if stype == 'command' and name == 'beq' and \
+           stype2 == 'command' and name2 in ['j', 'jal'] and \
+           stype3 == 'label' and name3 == args['args'][2]:
+            out_statements.append(('command', 'bne', \
+                {'args': [args['args'][0], args['args'][1], args2['args'][0]]}))
+            out_statements.append(statements[1 + 2])
+            i += 3
+        else:
+            out_statements.append(statements[i])
+            
+    return out_statements
+            
+    
 
 def optimize_global(statements):
     '''Optimize one-line statements in entire code.'''
+    statements = optimize_branch_jump_label(statements)
+    
     return filter(lambda s: not equal_mov(s) and not empty_shift(s), statements)
 
 def optimize_blocks(blocks):