Hash based code obfuscation?
If the inputs you're hashing aren't long enough with enough entropy, the hashes can be inverted by an adversary who is willing to brute force the entire range of possible inputs. 

For example, hashing abc provides little barrier to those who are dedicated at deobfuscated your program, as it takes almost no time to calculate hashes for all possible 3 character strings. 

The adversary can build a table of all inputs up to a certain size and proceed to crack your obfuscated data in negligible time. If your adversary has financial motivation, this probably will not protect your code. 

You could opt for additional protection by using slow, salted hashes, which are usually employed to protect passwords. Using a salt can prevent your adversary from precomputing the table before he has access to your source code. The downside is that using a slow hash in an effective manner will cause a non negligible performance hit to your application.