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| DSP_vecsumsq | |
| Sum of Squares | |||
DSP_vecsumsq | ||||
Function |
| int DSP_vecsumsq (const short *x, int nx) |
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Arguments |
| x[nx] | Input vector | |
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| nx | Number of elements in x. Must be multiple of 4 and ≥8. | |
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| return int | Sum of the squares | |
Description |
| This routine returns the sum of squares of the elements contained in the vector | ||
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| x[ ]. |
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Algorithm |
| This is the C equivalent of the assembly code without restrictions. Note that | ||
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| the assembly code is hand optimized and restrictions may apply. | ||
int DSP_vecsumsq(short x[ ], int nx)
{
int i, sum=0;
for(i=0; i<nx; i++)
{
sum += x[i]*x[i];
}
return(sum);
}
Special Requirements nx must be a multiple of 4 and greater than or equal to 32.
Implementation Notes
| - Bank Conflicts: No bank conflicts occur. | |
| - Interruptibility: The code is | |
| - The code is unrolled 4 times to enable full memory and multiplier | |
| bandwidth to be utilized. | |
Benchmarks | Cycles | nx/4 + 11 |
| Codesize | 188 bytes |
C64x+ DSPLIB Reference |
