On Mon, Sep 7, 2015 at 11:47 PM, Alan Modra <amo...@gmail.com> wrote: > In https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67378 analysis I show > the reason for this PR is that insns emitted by secondary reload > patterns are being generated without taking into account other reloads > that may have occurred. We run into this problem when an insn has a > pseudo that doesn't get a hard reg, and the pseudo is used in a way > that requires a secondary reload. In this case the secondary reload > is needed due to gcc generating a 64-bit gpr load from memory insn > with an address offset not a multiple of 4. > > Bootstrapped and regression tested powerpc64-linux. OK to apply? > gcc-5 and gcc-4.9 branches too? > > I haven't included a testcase in this patch, because the testcase in > the PR is quite horrible, and testcases triggering reload misbehaviour > tend to be unreliable. By unreliable, I mean a small change anywhere > in the compiler can result in the testcase passing even if this bug > was reintroduced at some future date. The testcase doesn't fail on > gcc-5, even though I'm fairly sure the same bug lurks there.. > > PR target/67378 > * config/rs6000/rs6000.c (rs6000_secondary_reload_gpr): Find > reload replacement for PRE_MODIFY address reg.
I'm okay with this patch, but I'd like Uli to double-check it when he has a moment. Thanks, David
