Methods and apparatus relating to techniques for fusing SIMD processing units. In an example, an apparatus comprises logic, at least partially comprising hardware logic, to receive an instruction set for execution on at least two graphics processing execution units, determine whether the instruction set requires data dependent addressing, and select between a synchronized execution environment for the at least two graphics processing units and an unsynchronized execution environment for the at least two graphics processing units based at least in part on the determination whether the instruction set requires data dependent addressing. Other embodiments are also disclosed and claimed.