On 11/18/2021 11:23 PM, Jojo R wrote:
— Jojo
在 2021年11月19日 +0800 AM12:13，Jeff Law <jeffreya...@gmail.com>，写道：
On 11/16/2021 7:20 PM, Jojo R via Gcc-patches wrote:
— Jojo
在 2021年11月16日 +0800 PM8:12，Richard Biener
<richard.guent...@gmail.com>，写道：
On Tue, Nov 16, 2021 at 12:45 PM Jojo R via Gcc-patches
<gcc-patches@gcc.gnu.org> wrote:
Skip renaming if instruction is noop move, and it will
been removed for performance.
Is there any (target specific) testcase you can add? Such
commits are
problematic
when later bisected to since the intent isn't clear.
I made a issue in bugzilla, please check it, thanks.
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103296
So what Richi is asking is can you construct a testcase for the
testsuite? Having a BZ is helpful because we can reference it in the
commit message, but a test, even if it's target specific, is even
better
from a long term maintenance standpoint.
I found this issue from the ISA extension vector of risc-v target, and
It has not been upstream by now, normal test case without vector isa
Is difficult to construct for this patch, but I think it’s simple and
useful for
other ISAs or targets, or recommit this patch after our risc-v Vector ISA
Is ready on master branch ?
Any suggestions ?
So I tried to trigger this on x86, but wasn't able with relatively light
testing.
My recommendation would be to add a little comment like this before the
change:
/* If this insn is a noop move, then do not rename in this chain as doing so
would inhibit removal of the noop move. */
OK with that change.
Thanks for your patience.
jeff
