Texas Instruments TMS320C64X - Manual (Page 67)

DSP_fir_cplx
4-39 C64x+ DSPLIB Reference
Special Requirements
- The number of coefficients nh must be a multiple of 2.
- The number of output samples nr must be a multiple of 4.
Implementation Notes
- Bank Conflicts: No bank conflicts occur.
- Interruptibility: The code is interrupt-tolerant but not interruptible.
- The outer loop is unrolled 4 times while the inner loop is not unrolled.
- Both inner and outer loops are collapsed in one loop.
- ADDAH and SUBAH are used along with PACKH2 to perform
accumulation, shift, and data packing.
- Collapsed one stage of epilog and prolog each.
Benchmarks Cycles nr * nh/2 + 7
Codesize 448 bytes