About the default march and optimizations

[Zhen Xin]

Buddies:
    Hi, I'm here. Didn't catch you on IRC for days.

After have a discuss with Zhang Le, I believe the right thing is
march=mips3, with -mfix-loongson2f-nop. This way the produced code can
run on both Loongson 2, and even any other MIPS3 compatible hardware.

march=loongson2f utilized the 3 additional instructions. As Fai said,
this gives little performance increase, but produces incompatible code.
Not a good idea for now, I think.

Without -mfix-loongson2f-nop, LS2F may hung. Horrible. XD

---
System Analyzing:

Total: 1300
FC6:	1 	 (0%)
FC10:	6 	 (0%)
FC11:	1216 	 (93%)
Non-FC:	74 	 (5%)

[Fai Wong]

Hi all,

I am still rebuilding the bits using loongson2f optimization, and
gnome will appear quite soon, I will do some brief test on it, if it
is ok, I can share the building environment like:
1. root tarball with yum
2. source rpms that changed
3. building instructions
so that every should be able to do the building first.

Changing the architecture should be as simple as changing one to two
lines in redhat-rpm-config package only, will do it after sharing
information. Hope I can have a basic environment of F12 this weekend.

Cheers,
Fai

2010/3/25 Genuine LoneStar - aka xinzhen :
> Buddies:
>        Hi, I'm here. Didn't catch you on IRC for days.
>
> After have a discuss with Zhang Le, I believe the right thing is
> march=mips3, with -mfix-loongson2f-nop. This way the produced code can
> run on both Loongson 2, and even any other MIPS3 compatible hardware.
>
> march=loongson2f utilized the 3 additional instructions. As Fai said,
> this gives little performance increase, but produces incompatible code.
> Not a good idea for now, I think.
>
> Without -mfix-loongson2f-nop, LS2F may hung. Horrible. XD
>
> System Analyzing:
>
> Total: 1300
> FC6:    1        (0%)
> FC10:   6        (0%)
> FC11:   1216     (93%)
> Non-FC: 74       (5%)
>
> mips mailing list
> [e-mail]
> https://admin.fedoraproject.org/mailman/listinfo/mips

[Gerard Braad]

> After have a discuss with Zhang Le, I believe the right thing is
> march=mips3, with -mfix-loongson2f-nop. This way the produced code can
> run on both Loongson 2, and even any other MIPS3 compatible hardware.

Last night I spoke with Ralf Baechle (MIPS kernel developer). This is
what he said about targeting

< Ralf> If you build for MIPS II it'll run on every 32-bit CPU
(except R2000/R3000 which are '85 / '87) vintage.
   < Ralf> MIPS III builds would run on anything 64-bit.

Eventually we want to target 'all' possible MIPS processors. But I can
accept for the moment to see the build of Fedora being targeted
towards the Loongson, since for now this is the only way for us the
verify and test if the packages work.

Gerard