Improve Arch PKGBUILD's CPU feature detection

packaging/main.sh

@@ -22,11 +22,11 @@ case "$1" in
         . ./resources/release-binaries.sh
         create_release_binaries
         ;;
-    pkgbuild-git-stable)
-        . ./resources/pkgbuild-git-stable.sh
-        create_pkgbuild_git_stable
+    pkgbuild-git-stable-optimized)
+        . ./resources/pkgbuild-git-stable-optimized.sh
+        create_pkgbuild_git_stable_optimized
         ;;
     *)
-    printf '\nusage: package.sh [target] <revision>\n\ntargets: release-binaries pkgbuild-git-stable\n\n'
+    printf '\nusage: package.sh [target] <revision>\n\ntargets: release-binaries pkgbuild-git-stable-optimized\n\n'
     ;;
 esac

packaging/resources/pkgbuild-git-stable-optimized.sh

@@ -1,6 +1,6 @@
 #!/bin/sh
 
-create_pkgbuild_git_stable() {
+create_pkgbuild_git_stable_optimized() {
     printf '\nGenerating PKGBUILD...\n'
     local source="git+https://github.com/rwinkhart/MUTN.git#tag=v\${pkgver}"
     printf "# Maintainer: Randall Winkhart <idgr at tutanota dot com>
@@ -12,7 +12,7 @@ arch=('x86_64' 'i686' 'i486' 'pentium4' 'aarch64' 'armv7h' 'riscv64')
 url='https://github.com/rwinkhart/MUTN'
 license=('MIT')
 depends=(gnupg)
-makedepends=(go util-linux gzip)
+makedepends=(go grep gzip)
 optdepends=(
     'wl-clipboard: Wayland clipboard support'
     'xclip: X11 clipboard support'
@@ -30,12 +30,12 @@ build() {
     # determine microarchitecture feature level
     case \$CARCH in
         'x86_64')
-            lscpuOutput=\$(lscpu | grep Flags)
-            if [ ! -z \"\$(echo \$lscpuOutput | grep avx512f)\" ]; then
+            cpuFlags=\$(grep -E 'flags\s+:\s' /proc/cpuinfo)
+            if [ ! -z \"\$(grep 'avx512f' <<< \"\$cpuFlags\")\" ]; then
                 export GOAMD64=v4
-            elif [ ! -z \"\$(echo \$lscpuOutput | grep avx2)\" ]; then
+            elif [ ! -z \"\$(grep 'avx2' <<< \"\$cpuFlags\")\" ]; then
                 export GOAMD64=v3
-            elif [ ! -z \"\$(echo \$lscpuOutput | grep sse4_2)\" ]; then
+            elif [ ! -z \"\$(grep 'sse4_2' <<< \"\$cpuFlags\")\" ]; then
                 export GOAMD64=v2
             else
                 export GOAMD64=v1