code review 6844080: runtime: fix madvise for freebsd/amd64

runtime: fix madvise for freebsd/amd64

Make use of carry clear condition instead of low or same.

[mikio, 2012-11-25 09:21:17]

Hello minux.ma@gmail.com, jsing@google.com (cc: golang-dev@googlegroups.com),

I'd like you to review this change to
https://code.google.com/p/go

[minux1, 2012-11-25 09:23:51]

https://codereview.appspot.com/6844080/diff/4001/src/pkg/runtime/sys_freebsd_...
File src/pkg/runtime/sys_freebsd_amd64.s (right):

https://codereview.appspot.com/6844080/diff/4001/src/pkg/runtime/sys_freebsd_...
src/pkg/runtime/sys_freebsd_amd64.s:193: CMPQ	AX, $0xfffffffffffff001
remove the comparison here.
a single JCC suffices.

you may want to reference pkg/syscall/asm_freebsd_amd64.s

[mikio, 2012-11-25 09:37:32]

> you may want to reference pkg/syscall/asm_freebsd_amd64.s

thx for helpful info.

https://codereview.appspot.com/6844080/diff/4001/src/pkg/runtime/sys_freebsd_...
File src/pkg/runtime/sys_freebsd_amd64.s (right):

https://codereview.appspot.com/6844080/diff/4001/src/pkg/runtime/sys_freebsd_...
src/pkg/runtime/sys_freebsd_amd64.s:193: CMPQ	AX, $0xfffffffffffff001
On 2012/11/25 09:23:52, minux wrote:
> remove the comparison here.
> a single JCC suffices.
> 
> you may want to reference pkg/syscall/asm_freebsd_amd64.s

Done.

[mikio, 2012-11-25 09:38:04]

Hello minux.ma@gmail.com, jsing@google.com (cc: golang-dev@googlegroups.com),

Please take another look.

[dave_cheney.net, 2012-11-25 09:40:49]

LGTM. Thanks Mikio. If you have tested this then I think you should submit it,
as the previous version was wrong, but wouldn't show up until things got tight.


On 25/11/2012, at 20:37, mikioh.mikioh@gmail.com wrote:

>> you may want to reference pkg/syscall/asm_freebsd_amd64.s
> 
> thx for helpful info.
> 
> 
>
https://codereview.appspot.com/6844080/diff/4001/src/pkg/runtime/sys_freebsd_...
> File src/pkg/runtime/sys_freebsd_amd64.s (right):
> 
>
https://codereview.appspot.com/6844080/diff/4001/src/pkg/runtime/sys_freebsd_...
> src/pkg/runtime/sys_freebsd_amd64.s:193: CMPQ    AX, $0xfffffffffffff001
> On 2012/11/25 09:23:52, minux wrote:
>> remove the comparison here.
>> a single JCC suffices.
> 
>> you may want to reference pkg/syscall/asm_freebsd_amd64.s
> 
> Done.
> 
> https://codereview.appspot.com/6844080/

[minux1, 2012-11-25 09:42:42]

LGTM.

[mikio, 2012-11-25 09:46:49]

*** Submitted as http://code.google.com/p/go/source/detail?r=db11b6a8c8f9 ***

runtime: fix madvise for freebsd/amd64

Make use of carry clear condition instead of low or same.

R=minux.ma, jsing, dave
CC=golang-dev
http://codereview.appspot.com/6844080