On Fri, 9 May 2025, Jakub Jelinek wrote: > On Fri, May 09, 2025 at 09:17:23AM +0200, Richard Biener wrote: > > RTL DSE forms store groups from unique invariant bases but that is > > confused when presented with constant addresses where it assigns > > one store group per unique address. That causes it to not consider > > 0x101:QI to alias 0x100:SI. Constant accesses can really alias > > to every object, in practice they appear for I/O and for access > > to objects fixed via linker scripts for example. So simply avoid > > registering a store group for them. > > > > Bootstrapped on x86_64-unknown-linux-gnu, testing in progress. > > > > OK? > > > > Thanks, > > Richard. > > > > PR rtl-optimization/120182 > > * dse.cc (canon_address): Constant addresses have no > > separate store group. > > > > * gcc.dg/torture/pr120182.c: New testcase. > > --- > > gcc/dse.cc | 5 ++- > > gcc/testsuite/gcc.dg/torture/pr120182.c | 42 +++++++++++++++++++++++++ > > 2 files changed, 46 insertions(+), 1 deletion(-) > > create mode 100644 gcc/testsuite/gcc.dg/torture/pr120182.c > > > > diff --git a/gcc/dse.cc b/gcc/dse.cc > > index ffc86ffabe5..2b99c660a9a 100644 > > --- a/gcc/dse.cc > > +++ b/gcc/dse.cc > > @@ -1190,7 +1190,10 @@ canon_address (rtx mem, > > address = strip_offset_and_add (address, offset); > > > > if (ADDR_SPACE_GENERIC_P (MEM_ADDR_SPACE (mem)) > > - && const_or_frame_p (address)) > > + && const_or_frame_p (address) > > + /* Literal addresses can alias any base, avoid creating a > > + group for them. */ > > + && ! CONST_INT_P (address)) > > Perhaps better CONST_SCALAR_INT_P instead of CONST_INT_P?
Do we ever get a wide_int for Pmode/ptr_mode? But sure, I can fix it that way. Richard. > Otherwise LGTM. > > Jakub > > -- Richard Biener <rguent...@suse.de> SUSE Software Solutions Germany GmbH, Frankenstrasse 146, 90461 Nuernberg, Germany; GF: Ivo Totev, Andrew McDonald, Werner Knoblich; (HRB 36809, AG Nuernberg)
