R600/SI: Add ShaderType attribute to some tests
R600/SI: Split global vector loads with more than 4 elements
R600/SI: Completely Disable TypeRewriter on compute
R600/SI: Add a pattern for i32 anyext

Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
R600/SI: Expand all v8[if]32 operations