tree-optimization/97482 - fix split_constant_offset of nop-conversions
split_constant_offset is confused about a nop-conversion from
unsigned long to sizetype and tries to prove non-overflowing
of the inner operation. Obviously the conversion could have been
elided so make sure split_constant_offset handles this properly.
It also makes sure that convert_to_ptrofftype does not introduce
conversions not necessary which in this case is the source for
the unnecessary conversion.
2020-10-15 Richard Biener <rguenther@suse.de>
PR tree-optimization/97482
* tree-data-ref.c (split_constant_offset_1): Handle
trivial conversions better.
* fold-const.c (convert_to_ptrofftype_loc): Elide conversion
if the offset is already ptrofftype_p.
* gcc.dg/vect/pr97428.c: New testcase.