On Thu, Oct 6, 2011 at 12:55 AM, Pedro Pedruzzi
wrote:
> Em 05-10-2011 17:11, Ulf Magnusson escreveu:
>> Hi,
>>
>> I've been experimenting with different methods for emulating the
>> signed overflow of an 8-bit CPU.
>
> You would like to check whether a 8-bit signed addition will overflow or
> not
On Thu, Oct 6, 2011 at 10:25 AM, Ulf Magnusson wrote:
> On Thu, Oct 6, 2011 at 12:55 AM, Pedro Pedruzzi
> wrote:
>> Em 05-10-2011 17:11, Ulf Magnusson escreveu:
>>> Hi,
>>>
>>> I've been experimenting with different methods for emulating the
>>> signed overflow of an 8-bit CPU.
>>
>> You would li
Ulf Magnusson writes:
> Might as well do
>
> bool overflowbit(unsigned int a, unsigned int b) {
> const unsigned int sum = a + b;
> return (a ^ b) & ~(a ^ sum) & 0x80;
> }
>
> But still not very good output compared to other approaches as expected.
How about:
bool overflowbit2(unsigne
On Thu, Oct 6, 2011 at 11:04 AM, Miles Bader wrote:
> Ulf Magnusson writes:
>> Might as well do
>>
>> bool overflowbit(unsigned int a, unsigned int b) {
>> const unsigned int sum = a + b;
>> return (a ^ b) & ~(a ^ sum) & 0x80;
>> }
>>
>> But still not very good output compared to other ap
Suddenly bugzilla went down.
Am I the only one seeing this?
--
PMatos
On 4 October 2011 09:41, Andrew Haley wrote:
> On 10/04/2011 08:08 AM, Iain Buclaw wrote:
>
>> I've have received news from Walter Bright that the license of the D
>> frontend has been assigned to the FSF. As the current maintainer of
>> GDC, I would like to get this moved forward, starting with g
On 10/06/2011 04:41 PM, Paulo J. Matos wrote:
Suddenly bugzilla went down.
Am I the only one seeing this?
Actually, the whole gcc.gnu.org since yesterday seems rather flaky. At
the moment it works fine for me, though.
Paolo.
On 06/10/11 15:41, Paulo J. Matos wrote:
Suddenly bugzilla went down.
Am I the only one seeing this?
Opps, now sorted.
--
PMatos
Paolo Carlini oracle.com> writes:
>
> On 10/06/2011 04:41 PM, Paulo J. Matos wrote:
> > Suddenly bugzilla went down.
> > Am I the only one seeing this?
> Actually, the whole gcc.gnu.org since yesterday seems rather flaky. At
> the moment it works fine for me, though.
Same symptoms as those on
Hi.
Instead of all the clever bit twiddling I have used code similar to
sum > UINT8_MAX
which just generates
cmp ax,255
seta al
which seems to be far more efficient (even the signed version gets optimized
down to the above single check).
Please could someone tell me if I have
On 10/05/2011 07:16 PM, David Miller wrote:
> From: David Bremner
> Date: Wed, 5 Oct 2011 19:08:41 -0700
>
>> What about treating these instructions as fused multiply-adds with
>> constant arguments?
>
> Richard Henderson (CC:'d) chatted with me the other day about this and
> made the same initi
On Thu, Oct 6, 2011 at 11:04 AM, Miles Bader wrote:
> How about:
>
> bool overflowbit2(unsigned int a, unsigned int b)
> {
> const unsigned int sum = a + b;
> return ~(a ^ b) & sum & 0x80;
> }
>
> ?
>
> I thik it has the same results as your function...
> [I just made a table
(I'll cross-post this to gcc and keep it on gcc-help after that.)
On Thu, Oct 6, 2011 at 4:46 PM, Andrew Haley wrote:
>
> inline int8_t as_signed_8 (unsigned int a) {
> a &= 0xff;
> return a & 0x80 ? (int)a - 0x100 : a;
> }
>
> int overflow(unsigned int a, unsigned int b) {
> int sum = as_sign
octoploid writes:
>> Actually, the whole gcc.gnu.org since yesterday seems rather flaky. At
>> the moment it works fine for me, though.
>
> Same symptoms as those on kernel.org
In gcc.gnu.org's case, apparently this was being caused by someone
hammering on the bugzilla server. A case of exces
* Ulf Magnusson:
> I've been experimenting with different methods for emulating the
> signed overflow of an 8-bit CPU. The method I've found that seems to
> generate the most efficient code on both ARM and x86 is
>
> bool overflow(unsigned int a, unsigned int b) {
> const unsigned int sum = (i
Georg-Johann Lay wrote, On 01/08/11 09:40:
Jon Grant wrote:
[.]
http://gcc.gnu.org/ml/gcc/2011-07/msg00106.html
CCed Gerald, I think he cares for that kind of things.
If he does not answer (it's vacation time) file a PR so that it won't be
forgotten.
Johann
Thank you. I filled a PR now:
Jonathan Wakely wrote, On 26/09/11 09:57:
[.]
Feel free to request a new option in Bugzilla to suppress the note,
that's the right place for this discussion.
Good point. I've created a ticket:
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50643
Regards, Jon
Hi,
as an addition to Balaji's answer. Please find attached an extract of a
sample front-end generating various types of tree nodes (e.g. arrays,
structs, ...). This used to work with an older version of GCC, but I'm
not sure if this still works with the most recent version. Anyway, it
should
Snapshot gcc-4.5-20111006 is now available on
ftp://gcc.gnu.org/pub/gcc/snapshots/4.5-20111006/
and on various mirrors, see http://gcc.gnu.org/mirrors.html for details.
This snapshot has been generated from the GCC 4.5 SVN branch
with the following options: svn://gcc.gnu.org/svn/gcc/branches
Thanks Andi, thanks Balaji.
2011/10/7 Andi Hellmund
>
> Hi,
>
> as an addition to Balaji's answer. Please find attached an extract of a
> sample front-end generating various types of tree nodes (e.g. arrays,
> structs, ...). This used to work with an older version of GCC, but I'm not
> sure if
Čau, čau!
Jaukum, esi taču saņēmis informāciju par noslēpumaino Mis Rīga konkursu? Pat,
ja neesi informēts, nekas!
Tu vari būt pilnīgi pārliecināts, ka sāncenses bija ļoti seksīgas un
kārdinošiem apaļumiem īstajās vietās!
Ja gribi viņas satikt un paspaidīt..
ej te: http://www.samphors.com/
Pedro Pedruzzi writes:
> On Thu, Oct 6, 2011 at 11:04 AM, Miles Bader wrote:
>> How about:
>>
>> bool overflowbit2(unsigned int a, unsigned int b)
>> {
>> const unsigned int sum = a + b;
>> return ~(a ^ b) & sum & 0x80;
>> }
>
> Miles, it is not the same. Take for example (0xff,
22 matches
Mail list logo
