Problem using modulo and sinus/cosinus functions with CCSv3.3, Embedded Coder and F28335

Hello, I'm using CodeComposer v3.3 and Matlab R2011b (Embedded Coder version 6.1).

I made a Simulink model where I generate a sawtooth between 0 and 2pi, at a given frequency; to do that, I made an integration of "2*pi*frequency", then I apply a 2pi-modulo using the "MOD" bloc in Simulink; then I apply sinus and cosinus on the result (with Simulink blocs "SIN" and "COS"). It works very well in simulation, but the behavior is wrong when I generate the code and execute it on F28335, especially at high frequency (sawtooth at more than 400Hz; sampling time is 100µs).

What could be wrong using MOD/SIN/COS bloc functions with embedded coder on F28335 DSP? Shall I use another math library in CCS? Let me know if you have any idea about that, or if you need any other information.

Thanks for reading. Regards, Julien