Programmable CPU architecture table for use with Gentoo. Fill out the table as you like. ``/proc/cpuinfo`` is used to match at least 1 entry in the table.

cpu_vendor.sh

# This gist is a useful little programmable tool I wrote to test and 
# expand CPU arcitecture auto-detection for Gentoo. It allows you to identify 
# for cross-compiler what machine you will be building the system for.
# ...and now its a programmable gist !  Enjoy ! - Heavy H. Paws
#

function cpu_arch () {
	local OS_ARCH=
	
  ## Examples
  ##
  ## Will identify:  32 and 64 bit intel processors
  ##                 32 and 64 bit amd processors
  ##                 raspberry pi 3 model b+ armv7
  ##                 pi zero
	CPU_TABLE=$(echo "amd64|flags,lm,vendor_id,genuineintel;"\
				           "x86|vendor_id,genuineintel;"\
			         		 "amd64|flags,lm,vendor_id,authenticamd;"\
					         "amd|vendor_id,authenticamd;"\
			        		 "armhf|flags,lm,model name,armv7;"\
			        		 "arm|model name,armv6")
	
	OS_CPU=$(IFS=';'
	for CPU_ENTRY in $CPU_TABLE
	do
		CPU_ARCH=$(echo "${CPU_ENTRY}" | cut -d'|' -f1)
		CPU_ENTRY=$(echo "${CPU_ENTRY}" | sed -e "s/^${CPU_ARCH}[|]//g")
		MATCH_RESULT=0
		while [[ "${CPU_ENTRY}x" != "x" ]]; do
			F1=$(echo "${CPU_ENTRY}" | cut -d ',' -f1)
			F2=$(echo "${CPU_ENTRY}" | cut -d ',' -f2)
			if cat /proc/cpuinfo | egrep -i "${F1}" | cut -d':' -f2 2>/dev/null | egrep -i "$F2" >/dev/null ; then
				MATCH_RESULT=1
			else
				MATCH_RESULT=0
			fi
			CPU_ENTRY=$(echo "${CPU_ENTRY}" | sed -e "s/^${F1}[,]${F2}[,]\?//g")
		done
		if [ $MATCH_RESULT -eq 1 ]; then
			echo -n "${CPU_ARCH}"
			break
		fi
	done
	IFS='')
	echo "${OS_CPU}"
}

# Example:  Set ARCH= parameter in /etc/portage/make.conf for cross-compiler.
#
# echo 'Setting ARCH...'
# perl -pi -e 's|(ARCH\=\")(.*)(")|${1}'$(cpu_arch)'${3}|g;' /etc/portage/make.conf