This is the mail archive of the
gcc@gcc.gnu.org
mailing list for the GCC project.
Re: ira.c update_equiv_regs patch causes gcc/testsuite/gcc.target/arm/pr43920-2.c regression
- From: Jeff Law <law at redhat dot com>
- To: Shiva Chen <shiva0217 at gmail dot com>, "gcc at gcc dot gnu dot org" <gcc at gcc dot gnu dot org>, gcc-patches at gcc dot gnu dot org
- Date: Mon, 20 Apr 2015 23:27:17 -0600
- Subject: Re: ira.c update_equiv_regs patch causes gcc/testsuite/gcc.target/arm/pr43920-2.c regression
- Authentication-results: sourceware.org; auth=none
- References: <CAH=PD7Z2s3Yw+nWkhKBzEVrvg=aeBLhL-rZJQ=VtpgOjZZ+DLA at mail dot gmail dot com> <55312EDF dot 90005 at redhat dot com> <CAH=PD7a0ofWfFBnJqD=6e5uYJY8v_GRjcvRuOBvy-x3EZNzFJg at mail dot gmail dot com>
On 04/20/2015 01:09 AM, Shiva Chen wrote:
Hi, Jeff
Thanks for your advice.
can_replace_by.patch is the new patch to handle both cases.
pr43920-2.c.244r.jump2.ori is the original jump2 rtl dump
pr43920-2.c.244r.jump2.patch_can_replace_by is the jump2 rtl dump
after patch can_replace_by.patch
Could you help me to review the patch?
Thanks. This looks pretty good.
I expanded the comment for the new function a bit and renamed the
function in an effort to clarify its purpose. From reviewing
can_replace_by, it seems it should have been handling this case, but
clearly wasn't due to implementation details.
I then bootstrapped and regression tested the patch on x86_64-linux-gnu
where it passed. I also instrumented that compiler to see how often
this code triggers. During a bootstrap it triggers a couple hundred
times (which is obviously a proxy for cross jumping improvements). So
it's triggering regularly on x86_64, which is good.
I also verified that this fixes BZ64916 for an arm-non-eabi toolchain
configured with --with-arch=armv7.
Installed on the trunk. No new testcase as it's covered by existing tests.
Thanks,,
jeff