28335 - Pragma for not optimizing a function away

Claudia

Hello,

I'm using 28335, I defined a function which is not directly called (in the program i jump to the specific address). Therefore the compiler is optimizing the function away. Can I somehow say the compiler to not optimize away this certain function? Is there a #pragma I can use?

Many thanks,

Claudia

over 12 years ago

0 Gautam Iyer over 12 years ago

Guru 192875 points

Hi,

Check this out:

http://e2e.ti.com/support/development_tools/code_composer_studio/f/81/t/98467.aspx

Regards,

Gautam

0 David M. Alter over 12 years ago

TI__Guru 61235 points

Claudia,

Use the RETAIN pragma when you declare the function in the source code:

#pragma RETAIN(foo)
void foo(void)
{
...
}

That should do it. See the C-Compiler Guide SPRU514F section 6.10.14 p.111 for more information on the pragma.

Regards,

David

0 Claudia over 12 years ago in reply to David M. Alter

Prodigy 100 points

Thanks a lot for your replies.

I tried the retain pragma but it didn't work. I have no idea what I'm doing wrong.

do you have any suggestions?

Thanks a lot,

Claudia

0 David M. Alter over 12 years ago in reply to Claudia

TI__Guru 61235 points

Claudia,

I suspect you have something subtle going on. The RETAIN pragma should have worked. I tested it myself prior to posting, and just tested it again. I am using C2000 cgtools v6.2.1. I have the optimizer set to -o4, and this causes my foo() function to get removed (because it is never called). When I use the RETAIN pragma, foo is retained.

Another thing you can try is inserting a harmless inline assembly statement into your function. I noticed that this also causes the function to be retained.

void foo(void)
{
asm(" ;dummy comment to keep function retained");

...
}

It wouldn't surprise me however if whatever is causing RETAIN to not work in your project also keeps the above trick from working.

Regards,

David

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28335 - Pragma for not optimizing a function away