On Wed, 2006-03-29 at 15:03 +0800, Tianwei Sheng wrote: > I need the field_info to help in alias analysis. for example: > int *p = &pair.a; > int *q = &pair.b; > > then if I can set length of "*p" to 4,ofset is '0' . for "*q" to > "8,4". also I know that p definitly points to pair.a and q points to > pair.b, then i can say "*p" and "*q" are not aliased with each other.
We already do this in 4.2 see access_can_touch_variable and overlap_subvar in tree-ssa-operands.c. Also, since 4.1, the pointer analysis at the tree level is field sensitive, so knows these things. See tree-ssa-structalias.c
