vrend: second round of micro-optimizations
- replace use of ctx->sub by a pre-dereferenced pointer, and also pass this pointer to function calls
- add more helper variables for pointer derefs to hint the compiler which derefs are re-used
- remove some obsolete or superfluous checks
In summary this gives another 3% speed boost in the Unigine Heaven benchmark, and also improves the reported FPS for most game traces we used for performance analysis.
Edited by Gert Wollny