Hsfpe source files

[lukekim]

Hi,

where can i find source files of SFPE libraries?

Thanks.

[lukekim]

Hi Stanislav, 

To  clarify my understanding is correct, if I change the floating point option to SFPE, the errors will be cleared.  Is it correct? 

Actually, I don't know the difference between Software and SFPE. 

Thanks. 

Your response helped me a lot. 

[stanish]

Hi Luke,

Yes your assumption is correct - errors should disappear if you switch to SPFP or SPFP_Only.

* SPFP (Single Precision Floating Point) is in fact kind of Hardware floating point support. This option causes that single precision - 32 bit float number calculations are compiled into a  single hardware instruction (or sequence of these instructions)

For more details please see  EFPU2 unit - http://www.nxp.com/assets/documents/data/en/reference-manuals/e200z760RM.pdf

Double precision (64-bit ) operations are emulated by SW since there is no hw support for this on chip.

*Software - this option must be used on the devices without any floating point unit and both single/float and double precision calculation are emulated using software routines with sequence of an integer instructions. These routines significantly decreases CPU speed performance since instead of a single instruction there is a complex routine.

Hope it helps.

Stan,

[stanish]

Luke,

The functions you are referring to are software emulated versions of float multiplication/conversion float to int.

These functions are being used by the compiler in case floating point flag is set to software (-fp soft).

Unfortunately there is no source code available for these functions, they are available only in object form 

<CW MCU v10.x>\MCU\PA_Support\ewl\EWL_Runtime\Runtime_PA\Source\sfpe.*.a"

Please make sure your compiler has -fp SPFP  or -fp SPFP_Only flag since it seems you are using a MCU with SPFP unit (e200z7) so you don't have to emulate single precision floating point operations using a library routines.

Hope it helps.

Stan

[lukekim]

Hi, Stanislav. 

I made a test function like this. 

void floatTestFunc() 

{

   int a;

   float x=1.0f,y=1.0f,z;

   z = x* y;

   a = (int) z;

} 

If I build upper codes with below libraries in Eclipse Codewarrior,  there is no error. 

- libc_E200z760_VLE. a

- librt_E200z760_VLE. a

But, if I build the codes without libraries, there are some errors like following. 

- undefined : '_f_ftoi'  Referenced 'from floatTestFunc' in...... 

- undefined : '_f_mul'  Referenced 'from floatTestFunc' in...... 

But,  I can't find related source files in upper folder. 

I would like to build with source files regarding floating points. 

Thanks. 

[stanish]

Hi Luke,

There is a complete .mcp project of FP library in CodeWarrior Classic:

<CW for MPC55xx and MPC56xx 2.10>\PowerPC_EABI_Support\MSL\MSL_C\PPC_EABI\Project\fdlibm.*.mcp

sources are available here:

<CW for MPC55xx and MPC56xx 2.10>\PowerPC_EABI_Support\MSL\MSL_C\PPC_EABI\SRC\

In CodeWarrior Eclipse (V10.7) SP floating point routines are located here:

<CW MCU v10.7>\MCU\PA_Support\ewl\EWL_C\src\sun_math\Single_precision\

Hope it helps.

Stan

[stanish]

Hi luke,

I guess you are looking math SPFP library source codes.

Could you be little more specific about the source files you are missing?

Which CodeWarrior do you use? CW for MPC55xx/56xx v2.x?

 Thanks!

Stan

[lukekim]

Hi, Stanislav. 

Thanks for your reply. 

Your guess is right. 

We use two versions of CW. 

- CW MCU V10. 7

- CW for MPC55XX and MPC56XX 2.10

We are using a  MPC5674F. 

thanks.