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ARM-software / CMSIS-DSP

CMSIS-DSP embedded compute library for Cortex-M and Cortex-A
https://arm-software.github.io/CMSIS-DSP
Apache License 2.0
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Why DSP is not enabled in arm dot prod q15. #195

Closed majorlin closed 5 days ago

majorlin commented 1 week ago

https://github.com/ARM-software/CMSIS-DSP/blob/7236701c153c9bbdec00568a2821a39039988d8f/Source/BasicMathFunctions/arm_dot_prod_q15.c#L154

christophe0606 commented 1 week ago

@majorlin Thanks for finding this.

I don't see any good reason for this. It is a very old change in the library.

christophe0606 commented 1 week ago

@majorlin I correct what I have just said. __SMLALD requires two Q15 packed in an int32. But this line is using *pSrcA++ to read a q15 from the tail of the vector.

So the instruction __SMLALD cannot be used here.