R600/SI: remove image sample writemask

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179164 91177308-0d34-0410-b5e6-96231b3b80d8
R600/SI: adjust writemask to only the used components

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179165 91177308-0d34-0410-b5e6-96231b3b80d8
R600/SI: dynamical figure out the reg class of MIMG

Depending on the number of bits set in the writemask.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179166 91177308-0d34-0410-b5e6-96231b3b80d8