question about the process of "CALLDATASIZE "

[smartcontract-detect-yzu]

i have one question that why have to check fixed calldatasize length “branch_array_size = [0,8,8+132,8+232]” alone.
the code is at：

MAIAN/tool/execute_block.py

Lines 334 to 346 in ab387e1

	# or Branch on 4 different FIXED sizes
	branch_array_size = [0,8,8+1*32,8+2*32]
	for one_branch_size in branch_array_size:
	storage2 = copy.deepcopy(storage)
	stack2 = copy.deepcopy(stack)
	trace2 = copy.deepcopy(trace)
	mmemory2 = copy.deepcopy(mmemory)
	data2 = copy.deepcopy(data)
	stack2.append( {'type':'constant','step':ops[pos]['id'], 'z3': BitVecVal(one_branch_size,256)} )
	execute_one_block(ops,stack2, pos+1, trace2, storage2, mmemory2, data2, configurations, search_op, search_function, jumpdepth, calldepth, debug, read_from_blockchain )

before that have already treat the calldatasize as symbolic variables, this is still cannot cover these fixed size?
the code is at

MAIAN/tool/execute_block.py

Lines 328 to 331 in ab387e1

	if -1 not in data2:
	data2['inputlength-'+str(calldepth)] = BitVec('inputlength-'+str(calldepth), 256)
	stack2.append( {'type':'constant','step':ops[pos]['id'], 'z3': data2['inputlength-'+str(calldepth)]} )
	execute_one_block(ops,stack2, pos+1, trace2, storage2, mmemory2, data2, configurations, search_op, search_function, jumpdepth, calldepth, debug, read_from_blockchain )

i wondering why these fixed size of calldatasize must be check again