is swizzle operators potentially faster?

Discussion created by FangQ on Feb 23, 2010
Latest reply on Feb 23, 2010 by Ceq

in the "ATI Stream SDK v2.01 Performance and Optimization" document, I noticed the following suggestion:

Vectorize. AMD GPU hardware is fundamentally a five-wide VLIW unit. Vectorization can
lead to substantially greater efficiency. The ALUPacking counter ...

does that mean using swizzle operators whenever possible is helpful to improve the speed? I know OpenCL does not support float3, I used float4 in most cases, will it be possible if I use float4 var; to do the calculation can gain any benefits in speed?