flac dev - Dec 2015 - FLAC__BYTES_PER_WORD==8 test results

On Dec 30, 2015, at 3:09 AM, Thomas Zander <thomas.e.zander at
googlemail.com> wrote:
> On 29 December 2015 at 21:50, lvqcl <lvqcl.mail at gmail.com> wrote:
>> So, does it make sense to #define FLAC__BYTES_PER_WORD (in bitreader.c)
>> as 4 for 32-bit and as 8 for 64-bit targets?
> 
> Your tests so far imply this is a sensible default.
> I'd say go ahead. We can always change it if it turns out there is a
> better option.
> 
> Riggs
What's wrong with something incredible simple, like:

#define FLAC__BYTES_PER_WORD (sizeof(int))

?

Brian Willoughby wrote:
> What's wrong with something incredible simple, like:
> 
> #define FLAC__BYTES_PER_WORD (sizeof(int))
The fact that it actually is not correct. We want to determine
the size in bits of the CPU registers.

Here's what I know:

                      sizeof(int)     sizeof (long)
   ---------------+----------------+-----------------
   32 bit Linux   |       4        |       4
   64 bit Linux   |       4        |       8
   32 bit windows |       4        |       4
   64 bit windows |       4        |       4

Note that sizeof(long) on 64 bit windows is 4!

Most other unixen follow the LP64 scheme used by Linux.

Erik
-- 
----------------------------------------------------------------------
Erik de Castro Lopo
http://www.mega-nerd.com/

On 31-Dec-15 09:00, Erik de Castro Lopo wrote:
> Brian Willoughby wrote:
>
>> What's wrong with something incredible simple, like:
>>
>> #define FLAC__BYTES_PER_WORD (sizeof(int))
> The fact that it actually is not correct. We want to determine
> the size in bits of the CPU registers.
>
> Here's what I know:
>
>                        sizeof(int)     sizeof (long)
>     ---------------+----------------+-----------------
>     32 bit Linux   |       4        |       4
>     64 bit Linux   |       4        |       8
>     32 bit windows |       4        |       4
>     64 bit windows |       4        |       4
>
> Note that sizeof(long) on 64 bit windows is 4!
>
> Most other unixen follow the LP64 scheme used by Linux.
>
> Erik
On Windows x64 sizeof(long) is 4, but sizeof(ptrdiff_t) is 8.

Any reasons for not using sizeof(ptrdiff_t)?

Cheers,
Cristian.
-------------- next part --------------
An HTML attachment was scrubbed...
URL:
http://lists.xiph.org/pipermail/flac-dev/attachments/20151231/751f92da/attachment.htm