Package: kfreebsd-5
Severity: wishlist
Tags: patch

I'm attaching a patch that should improve performance on high subarches:

  - i486 gets -march=i486 and -mtune=i686
  - i586 gets -march=i586
  - i686 gets -march=i686

Unless this causes runtime errors, I think there's no drawback in adding -march
for the respective subarches.

For -mtune, though, it is not clear what is better.  My opinion is that, since
the default kernel is the i486 one, it'll most often be used on i686, so it's
probably better to tune for that cpu (but keeping compatibility with i486).
This isn't only the case for installs on which the user didn't bother to switch
to -586 or -686, but also for Live systems that are forced to use -486.

As for i586, since they installed this package explicitly, it most likely means
we're really on a i586 cpu, so -mtune would do more harm than good.

This patch is a followup to the one in #332836.

-- System Information:
Debian Release: testing/unstable
  APT prefers unstable
  APT policy: (500, 'unstable')
Architecture: i386 (i686)
Shell:  /bin/sh linked to /bin/bash
Kernel: Linux 2.6.11-1-k7
Locale: LANG=en_US, LC_CTYPE=en_US (charmap=ANSI_X3.4-1968) (ignored: LC_ALL 
set to C)
diff -ur config.old/486 config/486
--- config.old/486      2005-10-09 11:58:29.000000000 +0200
+++ config/486  2005-10-09 12:01:03.000000000 +0200
@@ -5,6 +5,7 @@
 cpu            I486_CPU
 cpu            I586_CPU
 cpu            I686_CPU
+makeoptions    COPTFLAGS="-march=i486 -mtune=i686"
 ident          Debian-i486
 
 # To statically compile in device wiring instead of /boot/device.hints
diff -ur config.old/586 config/586
--- config.old/586      2005-10-09 11:58:29.000000000 +0200
+++ config/586  2005-10-09 12:01:15.000000000 +0200
@@ -4,6 +4,7 @@
 machine                i386
 cpu            I586_CPU
 cpu            I686_CPU
+makeoptions     COPTFLAGS="-march=i586"
 ident          Debian-i586
 
 # To statically compile in device wiring instead of /boot/device.hints
diff -ur config.old/686 config/686
--- config.old/686      2005-10-09 11:56:00.000000000 +0200
+++ config/686  2005-10-09 12:01:29.000000000 +0200
@@ -3,6 +3,7 @@
 
 machine                i386
 cpu            I686_CPU
+makeoptions     COPTFLAGS="-march=i686"
 ident          Debian-i686
 
 # To statically compile in device wiring instead of /boot/device.hints
diff -ur config.old/686-smp config/686-smp
--- config.old/686-smp  2005-10-09 11:56:00.000000000 +0200
+++ config/686-smp      2005-10-09 12:01:42.000000000 +0200
@@ -3,6 +3,7 @@
 
 machine                i386
 cpu            I686_CPU
+makeoptions     COPTFLAGS="-march=i686"
 ident          Debian-i686-SMP
 
 # To statically compile in device wiring instead of /boot/device.hints

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