Texas Instruments TMS320C64X manual Loads input x and coefficient w as double words

DSP_fft

Special Requirements

-In-place computation is not allowed.

-nx must be a power of 4 and 4 ≤ nx ≤ 65536.

-Input x[ ] and output y[ ] are stored on double-word aligned boundaries.

-Input data x[ ] is stored in the order real0, img0, real1, img1, ...

-The FFT coefficients (twiddle factors) must be double-word aligned and are generated using the program tw_fft16x16 provided in the directory ‘support\fft’.

Implementation Notes

	- Bank Conflicts: No bank conflicts occur.
	- Interruptibility: The code is interrupt-tolerant but not interruptible.
	- Loads input x[ ] and coefficient w[ ] as double words.
	- Both loops j and i0 shown in the C code are placed in the inner loop of the
	assembly code.
Benchmarks	Cycles	1.25 * nx * log4(nx) – 0.5 * nx + 23 * log4(nx) – 1
	Codesize	984 bytes

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