Subject: Convenient sysctl/uname option for cpu/arch level?
To: None <>
From: David Brownlee <>
List: tech-toolchain
Date: 03/14/2001 21:45:08
	I've been playing with having pkgsrc pick the appropriate
	'best' optimisation level when compiling anything on various
	boxes around here, and I'm having a little fun determining the
	appropriate compiler flags for each CPU.

	I knocked together a quick script for some i486 and sparc boxes,
	(below) and in the process noted there does not seem to be an
	obvious method of finding the appropriate compiler flags.

	I wonder if it might make sense to have a sysctl or uname option
	to output the appropriate 'supersparc' or 'pentiumpro' value based
	on the current CPU?

hw_model=`sysctl -n hw.model`
case $hw_model in

    # i386
    *386-class*)                FLAGS='-march=i386'             ;;
    *486-class*)                FLAGS='-march=i486'             ;;
    *586-class*)                FLAGS='-march=pentium'          ;;
    *686-class*)                FLAGS='-march=pentiumpro'       ;;

    # sparc
    MB86904*)                   FLAGS="-mcpu=supersparc"        ;; # ss5
    TMS390Z50*)                 FLAGS="-mcpu=supersparc"        ;; # ss10/ss20
    MB86930* | MB86934*)        FLAGS="-mcpu=sparclite"         ;; # from gcc
    MB86900/1A*)                FLAGS="-mcpu=cypress"           ;; # ss1+

    *)                          echo "Unknown hw.model '$hw_model'" >&2

echo $FLAGS
exit 0

		David/absolute		-- No hype required --