> -----Original Message----- > From: Richard Sandiford <richard.sandif...@arm.com> > Sent: 29 May 2020 11:59 > To: Alex Coplan <alex.cop...@arm.com> > Cc: gcc-patches@gcc.gnu.org; nd <n...@arm.com>; Richard Earnshaw > <richard.earns...@arm.com>; Marcus Shawcroft <marcus.shawcr...@arm.com>; > Kyrylo Tkachov <kyrylo.tkac...@arm.com> > Subject: Re: [PATCH] [aarch64] Fix PR94591: GCC generates invalid rev64 > insns > > Alex Coplan <alex.cop...@arm.com> writes: > > On 19/05/2020 17:59, Richard Sandiford wrote: > >> Alex Coplan <alex.cop...@arm.com> writes: > >> > Hello, > >> > > >> > This patch fixes PR94591. The problem was the function > aarch64_evpc_rev_local() > >> > matching vector permutations that were not reversals. In particular, > prior to > >> > this patch, this function matched the identity permutation which led > to > >> > generating bogus REV64 insns which were rejected by the assembler. > >> > > >> > Testing: > >> > - New regression test which passes after applying the patch. > >> > - New test passes on an x64 -> aarch64-none-elf cross. > >> > - Bootstrap and regtest on aarch64-linux-gnu. > >> > > >> > OK to install? > >> > > >> > Thanks, > >> > Alex > >> > > >> > --- > >> > > >> > gcc/ChangeLog: > >> > > >> > 2020-05-19 Alex Coplan <alex.cop...@arm.com> > >> > > >> > PR target/94591 > >> > * config/aarch64/aarch64.c (aarch64_evpc_rev_local): Don't match > >> > identity permutation. > >> > > >> > gcc/testsuite/ChangeLog: > >> > > >> > 2020-05-19 Alex Coplan <alex.cop...@arm.com> > >> > > >> > PR target/94591 > >> > * gcc.c-torture/execute/pr94591.c: New test. > >> > >> OK, thanks. > >> > >> Richard > > > > I've just tested this patch on gcc-{8,9,10} release branches: > > bootstraps+regtests on aarch64-linux-gnu came back clean. > > > > Since this was a regression introduced in GCC 8, is it OK to backport > > the fix to those release branches now? > > Yeah, OK for the branches too.
Installed on the branches. Thanks, Alex