Date: Thu, 13 Jan 2000 23:10:02 -0800 (PST) From: John and Jennifer Reynolds <jjreynold@home.com> To: freebsd-doc@freebsd.org Subject: Re: docs/11258: suggestion to refine npx.4 Message-ID: <200001140710.XAA79492@freefall.freebsd.org>
next in thread | raw e-mail | index | archive | help
The following reply was made to PR docs/11258; it has been noted by GNATS. From: John and Jennifer Reynolds <jjreynold@home.com> To: freebsd-gnats-submit@FreeBSD.org Cc: mzaki@e-mail.ne.jp Subject: Re: docs/11258: suggestion to refine npx.4 Date: Fri, 14 Jan 2000 00:00:26 -0700 (MST) I dug into this a little and Motomichi is quite right in his description of what MATH_EMULATE will not do (no transcendental functions are emulated). I cannot speak for the precision problems that the GPL'ed emulator from Linux might suffer from, but the following patch (against 3.4-STABLE) to npx.4 takes Motomichi's basic comments and includes them. I believe this will suffice for one of you wonderful doc committers to close this PR :) --- /usr/src/share/man/man4/man4.i386/npx.4 Wed Sep 1 20:55:52 1999 +++ npx.4 Thu Jan 13 23:52:10 2000 @@ -38,6 +38,8 @@ .Nd Numeric Processing Extension coprocessor and emulator .Sh SYNOPSIS .Cd "options MATH_EMULATE" +or +.Cd "options GPL_MATH_EMULATE" .\" XXX this is awful hackery to get it to work right... -- cgd .Cd "device npx0 at isa? port IO_NPX tty irq 13" .Sh DESCRIPTION @@ -62,6 +64,16 @@ It will provide support for the instructions normally executed by the NPX. If there is no NPX in the system and the kernel is not built with math emulation, the system will not boot. +.Pp +You can choose to use a much more fully-featured math emulator (under the +GPL license) by including the option "GPL_MATH_EMULATE" in your kernel +configuration file +.Sy instead +of the "MATH_EMULATE" option. +.Pp +The +.Sy GENERIC +kernel configuration uses the "MATH_EMULATE" option. .Sh CAVEATS The emulator is much slower than the NPX coprocessor. This will result in poor floating-point math performance @@ -72,5 +84,5 @@ the CPU wired properly. If this is the case, the emulator must be used if consistent system operation is desired. .Pp -Emulation of the transcendental functions instructions is incorrect. -Emulation of other instructions is suspect. +When using the default "MATH_EMULATE" code, transcendental function +instructions are not implemented. Emulation of other instructions is suspect. -Jr -- =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= John Reynolds Chandler Capabilities Engineering, CDS, Intel Corporation jreynold@sedona.ch.intel.com My opinions are mine, not Intel's. Running jjreynold@home.com FreeBSD 3.4-STABLE. FreeBSD: The Power to Serve. http://members.home.com/jjreynold/ Come join us!!! @ http://www.FreeBSD.org/ =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-doc" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200001140710.XAA79492>