Reduces vertex shader instruction counts in DOTA2 by 6.42%, L4D2 by
4.61%, and CS:GO by 5.71%.
total instructions in shared programs: 1500153 -> 1498191 (-0.13%)
instructions in affected programs: 59919 -> 57957 (-3.27%)
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>