[llvm-dev] Enable vectorizer-maximize-bandwidth by default?
Nema, Ashutosh via llvm-dev
llvm-dev at lists.llvm.org
Thu Jun 1 04:47:16 PDT 2017
We enabled “vectorizer-maximize-bandwidth” and ran SPEC CPU2006 (base,rate) on Ryzen 8 core, 16 copies with below config:
Base: -m64 -O3 -march=znver1 -mavx2
Base + VMB: -m64 -O3 -march=znver1 -mavx2 -mllvm -vectorizer-maximize-bandwidth
There’s a small uplift for gcc and some small regression for sjeng. Others are within noise levels.
Base/(Base + VMB)
* Ratio more than 1 indicates vectorizer-maximize-bandwidth is improving the performance
* Ratio less than 1 indicates vectorizer-maximize-bandwidth is regressing the performance.
* Ratio 1 indicates no change.
From: llvm-dev [mailto:llvm-dev-bounces at lists.llvm.org] On Behalf Of Adam Nemet via llvm-dev
Sent: Tuesday, May 30, 2017 9:47 PM
To: Chandler Carruth <chandlerc at gmail.com>
Cc: llvm-dev <llvm-dev at lists.llvm.org>
Subject: Re: [llvm-dev] Enable vectorizer-maximize-bandwidth by default?
On May 30, 2017, at 12:58 AM, Chandler Carruth <chandlerc at gmail.com<mailto:chandlerc at gmail.com>> wrote:
On Fri, May 19, 2017 at 4:01 PM Adam Nemet via llvm-dev <llvm-dev at lists.llvm.org<mailto:llvm-dev at lists.llvm.org>> wrote:
I will run it on Cyclone/AArch64 next week.
FYI, we're still waiting on these Adam…
I was going to test spec but this does not seem to trigger on spec according to Dehao, so there is really no reason for me to test this. We have some spec perf bots that test trunk; if there is some unexpected regression we should pick it up. Sorry for not being explicit about this.
-------------- next part --------------
An HTML attachment was scrubbed...
More information about the llvm-dev