On Fri, Oct 13, 2017 at 5:04 PM, Bin Cheng <bin.ch...@arm.com> wrote: > Hi, > I ran into this when investigating PR82369 which we failed to find base > object. > This simple patch tries harder to find base object by expanding base address > in alloc_iv. In general, we don't want to do aggressive expansion, but this > case is fine because finding base object means reduction happened during the > expansion.
I'm not sure. Does simplification happen for the testcase when expanding? > And it's good to have base object for address type iv_uses. Because we find related candidates via base-object? It looks like we could avoid excessive expansion by doing determine_base_object together with expr expansion given the base object search is linear. We can simply follow SSA defs until we reach a suitable base and upon unwinding build the base expression? Richard. > Bootstrap and test on x86_64 and AArch64. Is it OK? > > Thanks, > bin > 2017-10-12 Bin Cheng <bin.ch...@arm.com> > > * tree-scalar-evolution.c (alloc_iv): New parameter controlling > base expansion for finding base object. > (find_interesting_uses_address): Adjust call to alloc_iv. > > gcc/testsuite > 2017-10-12 Bin Cheng <bin.ch...@arm.com> > > * gcc.dg/tree-ssa/ivopt_6.c: New test.
