> So no, there are plenty of easy ways to fool the optimizer by obfuscation.
If you mean fooling the compiler by the source code obfuscation, it won't – by the time the first optimisation pass arrives, the source had already been transformed into an abstract syntax tree and the source code obfuscation becomes irrelevant.
Multiple optimiser passes do take place, but they are bounded in time – it is not an accepted expectation that the optimiser will spend a – theoretically – indefinite amount of time trying to arrive at the most perfect instruction sequence.
There was a GNU project a long time ago, «superoptimiser», which, given a sequence of instructions, would spend a very long time trying to optimise it into oblivion. The project was more of an academic exercise, and it has been long abandoned since.
If you mean fooling the compiler by the source code obfuscation, it won't – by the time the first optimisation pass arrives, the source had already been transformed into an abstract syntax tree and the source code obfuscation becomes irrelevant.
Multiple optimiser passes do take place, but they are bounded in time – it is not an accepted expectation that the optimiser will spend a – theoretically – indefinite amount of time trying to arrive at the most perfect instruction sequence.
There was a GNU project a long time ago, «superoptimiser», which, given a sequence of instructions, would spend a very long time trying to optimise it into oblivion. The project was more of an academic exercise, and it has been long abandoned since.