Re: [PATCH] tree-optimization/110243 - kill off IVOPTs split_offset

[Richard Sandiford <richard.sandiford@arm.com>]

Jeff Law <jeffreyalaw@gmail.com> writes:
> On 6/16/23 06:34, Richard Biener via Gcc-patches wrote:
>> IVOPTs has strip_offset which suffers from the same issues regarding
>> integer overflow that split_constant_offset did but the latter was
>> fixed quite some time ago.  The following implements strip_offset
>> in terms of split_constant_offset, removing the redundant and
>> incorrect implementation.
>> 
>> The implementations are not exactly the same, strip_offset relies
>> on ptrdiff_tree_p to fend off too large offsets while split_constant_offset
>> simply assumes those do not happen and truncates them.  By
>> the same means strip_offset also handles POLY_INT_CSTs but
>> split_constant_offset does not.  Massaging the latter to
>> behave like strip_offset in those cases might be the way to go?
>> 
>> Bootstrapped and tested on x86_64-unknown-linux-gnu.
>> 
>> Comments?
>> 
>> Thanks,
>> Richard.
>> 
>> 	PR tree-optimization/110243
>> 	* tree-ssa-loop-ivopts.cc (strip_offset_1): Remove.
>> 	(strip_offset): Make it a wrapper around split_constant_offset.
>> 
>> 	* gcc.dg/torture/pr110243.c: New testcase.
> Your call -- IMHO you know this code far better than I.

+1, but LGTM FWIW.  I couldn't see anything obvious (and valid)
that split_offset_1 handles and split_constant_offset doesn't.

Thanks,
Richard