Begin work on supporting segmented reductions.
Begin work on supporting segmented reductions.

diku-dk/futhark,mrakgr/futhark,HIPERFIT/futhark,diku-dk/futhark,mrakgr/futhark,ihc/futhark,HIPERFIT/futhark,HIPERFIT/futhark,CulpaBS/wbBach,mrakgr/futhark,diku-dk/futhark,diku-dk/futhark,ihc/futhark,ihc/futhark,diku-dk/futhark