C54X C structure packing

Anyone know how to force the C54X C compiler to pack C structures with
short and long types?

Thanks,

John

John wrote:
> Anyone know how to force the C54X C compiler to pack C structures with
> short and long types?
> 
> Thanks,
> 
> John

See if is supports this:
http://publib.boulder.ibm.com/infocenter/macxhelp/v6v81/index.jsp?topic=/com.ibm.vacpp6m.doc/compiler/ref/rnpgpack.htm

--
Les Cargill

John <sampson164@gmail.com> writes:

> Anyone know how to force the C54X C compiler to pack C structures with
> short and long types?

In gcc there is a -fpack-struct compiler option. Seems like there was
something similar in the TI codegen tools - perhaps a PRAGMA?
-- 
Randy Yates                      % "She has an IQ of 1001, she has a jumpsuit
Digital Signal Labs              %            on, and she's also a telephone."
mailto://yates@ieee.org          % 
http://www.digitalsignallabs.com %        'Yours Truly, 2095', *Time*, ELO   

On Dec 10, 7:29&#4294967295;pm, Les Cargill <lcargil...@comcast.net> wrote:
> John wrote:
> > Anyone know how to force the C54X C compiler to pack C structures with
> > short and long types?
>
> > Thanks,
>
> > John
>
> See if is supports this:http://publib.boulder.ibm.com/infocenter/macxhelp/v6v81/index.jsp?top...
>
> --
> Les Cargill

Nope

On Dec 10, 8:26&#4294967295;pm, Randy Yates <ya...@ieee.org> wrote:
> John <sampson...@gmail.com> writes:
> > Anyone know how to force the C54X C compiler to pack C structures with
> > short and long types?
>
> In gcc there is a -fpack-struct compiler option. Seems like there was
> something similar in the TI codegen tools - perhaps a PRAGMA?
> --
> Randy Yates &#4294967295; &#4294967295; &#4294967295; &#4294967295; &#4294967295; &#4294967295; &#4294967295; &#4294967295; &#4294967295; &#4294967295; &#4294967295;% "She has an IQ of 1001, she has a jumpsuit
> Digital Signal Labs &#4294967295; &#4294967295; &#4294967295; &#4294967295; &#4294967295; &#4294967295; &#4294967295;% &#4294967295; &#4294967295; &#4294967295; &#4294967295; &#4294967295; &#4294967295;on, and she's also a telephone."
> mailto://ya...@ieee.org &#4294967295; &#4294967295; &#4294967295; &#4294967295; &#4294967295;%http://www.digitalsignallabs.com% &#4294967295; &#4294967295; &#4294967295; &#4294967295;'Yours Truly, 2095', *Time*, ELO &#4294967295;

I have searched the TI docs for that.

John

John wrote:
> On Dec 10, 7:29 pm, Les Cargill <lcargil...@comcast.net> wrote:
>> John wrote:
>>> Anyone know how to force the C54X C compiler to pack C structures with
>>> short and long types?
>>> Thanks,
>>> John
>> See if is supports this:http://publib.boulder.ibm.com/infocenter/macxhelp/v6v81/index.jsp?top...
>>
>> --
>> Les Cargill
> 
> Nope

Bummer. Check to see what it does - I bet it packs 'em on
16 bit boundaries - iow:

typedef struct {
    unsigned char a;
    unsigned char b;
    long  c;
} magilla;

would result in the offset of "c" being two machine words to
the right of the start of struct. I simply don't remember
any more, it's been too long.

Oh, if they'd only defined the behavior of bit fields in 'C',
the world would be a much better place.

--
Les Cargill

John <sampson164@gmail.com> writes:

> Anyone know how to force the C54X C compiler to pack C structures with
> short and long types?

John, 

The minimum addressable unit of the 54x is 16 bits! (Doh!)
-- 
Randy Yates                      % "Though you ride on the wheels of tomorrow,
Digital Signal Labs              %  you still wander the fields of your
mailto://yates@ieee.org          %  sorrow."
http://www.digitalsignallabs.com % '21st Century Man', *Time*, ELO

Randy Yates <yates@ieee.org> writes:

> John <sampson164@gmail.com> writes:
>
>> Anyone know how to force the C54X C compiler to pack C structures with
>> short and long types?
>
> John, 
>
> The minimum addressable unit of the 54x is 16 bits! (Doh!)

Wups. Never mind....
-- 
Randy Yates                      % "So now it's getting late,
Digital Signal Labs              %    and those who hesitate
mailto://yates@ieee.org          %    got no one..."
http://www.digitalsignallabs.com % 'Waterfall', *Face The Music*, ELO

Randy Yates  <yates@ieee.org> wrote:

>The minimum addressable unit of the 54x is 16 bits! (Doh!)

Whoa.  A clear example of an engineer issuing a spec before 10:00 a.m.,
and/or without his morning coffee.

Steve

John wrote:
> Anyone know how to force the C54X C compiler to pack C structures with
> short and long types?

Roll your own convertor of a structure to an array of bytes and back; 
with explicit conversion of each of the fields. This solves usual 
problem with packing and alignment.

VLV