From: Timo Heister <timo.heister@gmail.com>
Date: Mon, 21 Mar 2022 18:14:58 +0000 (-0400)
Subject: native optimizations: enable -O3
X-Git-Tag: v9.4.0-r1~5^2
X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=refs%2Fpull%2F284%2Fhead;p=candi.git

native optimizations: enable -O3

We found out that -O3 makes a measurable difference in matrix-free
performance for recent gcc versions. Enable this when the user requests
native optimizations.
---

diff --git a/deal.II-toolchain/packages/dealii.package b/deal.II-toolchain/packages/dealii.package
index 58d399b..ea1ed0b 100644
--- a/deal.II-toolchain/packages/dealii.package
+++ b/deal.II-toolchain/packages/dealii.package
@@ -38,7 +38,8 @@ fi
 # Choice of whether native compiler optimizations should be enabled
 if [ ${NATIVE_OPTIMIZATIONS} = ON ]; then
     CONFOPTS="${CONFOPTS} \
-      -D CMAKE_CXX_FLAGS='-march=native'"
+      -D CMAKE_CXX_FLAGS='-march=native' \
+      -D CMAKE_CXX_FLAGS_RELEASE='-O3'"
 fi
 
 if [ ${USE_DEAL_II_CMAKE_MPI_COMPILER} = ON ]; then