pragma unroll

Discussion created by rick.weber on Feb 15, 2011
Latest reply on Feb 16, 2011 by MicahVillmow

I have an array that is always small, but whose size isn't known until after preprocessor evaluation. How can I fully unroll all loops that access this array without resorting to code generators (which I'm considering adding to clUtil as a pre-preprocessor)? Also, if the compiler is able to compute indices at compile time, will this array reside in registers?


#define arraySize 4

__kernel void foo()


  unsigned int array[arraySize]; //Want to be in registers

#pragma unroll arraySize

  for(unsigned int i = 0; i < arraySize; i++)


    //do something with array;


This code is equivilent to 

__kernel void foo()


  unsigned int array1;

  unsigned int array2;

  unsigned int array3;

  unsigned int array4;

  //do something with array1, 2, 3, 4