If the big block entry conditions are correct, then the big block exit conditions are correct.
A sequence of blocks is correct if the exit conditions of each block matches the entry conditions of the following block. Execution enters each block at the block's entry point, and leaves through the block's exit point. The whole sequence can be regarded as a single block, with an entry point and an exit point.
Rule 2 of Structured Programming: Two or more code blocks in sequence are structured.
The assembly language implementation of this rule is the same as rule one: a programmer must consciously follow the rule. This means that there must be no jumps elsewhere in the code to points inside the blocks.
Are if-then-else structures possible in assembly language?