def _int_sub(optimizer, box1, box2):
if isinstance(box2, ConstInt):
if box2.value == 0:
return box1
if isinstance(box1, ConstInt):
return ConstInt(box1.value - box2.value)
resbox = BoxInt()
optimizer.propagate_forward(ResOperation(rop.INT_SUB, [box1, box2], resbox))
return resbox
def _strgetitem(optimizer, strbox, indexbox, mode):
if isinstance(strbox, ConstPtr) and isinstance(indexbox, ConstInt):
if mode is mode_string:
s = strbox.getref(lltype.Ptr(rstr.STR))
return ConstInt(ord(s.chars[indexbox.getint()]))
else:
s = strbox.getref(lltype.Ptr(rstr.UNICODE))
return ConstInt(ord(s.chars[indexbox.getint()]))
resbox = BoxInt()
optimizer.propagate_forward(ResOperation(mode.STRGETITEM, [strbox, indexbox],
resbox))
return resbox
def _int_add(optimizer, box1, box2):
if isinstance(box1, ConstInt):
if box1.value == 0:
return box2
if isinstance(box2, ConstInt):
return ConstInt(box1.value + box2.value)
elif isinstance(box2, ConstInt) and box2.value == 0:
return box1
if optimizer is None:
return None
resbox = BoxInt()
optimizer.propagate_forward(ResOperation(rop.INT_ADD, [box1, box2], resbox))
return resbox
