Arguments and Conventions Used

3.1 Arguments and Conventions Used

The following convention has been used when describing the arguments for each individual function:

Table 3−1. Argument Conventions

Argument Description

x,y

Argument reflecting input data vector

rArgument reflecting output data vector

nx,ny,nr Arguments reflecting the size of vectors x,y, and r, respectively. For functions in the case nx = ny = nr, only nx has been used across.

hArgument reflecting filter coefficient vector (filter routines only)

nh

Argument reflecting the size of vector h

wArgument reflecting FFT coefficient vector (FFT routines only)

Some C64x+ functions have additional restrictions due to optimization using new features such as higher multiply throughput. While these new functions perform better, they can also lead to problems if not carefully used. For example, DSP_autocor_rA8 is faster than DSP_autocor, but the output buffer must be aligned to an 8−byte boundary. Therefore, the new functions are named with any additional restrictions. Three types of restrictions are specified to a pointer: minimum buffer size (M), buffer alignment (A), and the number of elements in the buffer to be a multiple of an integer (X).The following convention has been used when describing the arguments for each individual function:

A kernel function foo with two parameters, m and n, with the following restrictions:

m −> Minimum buffer size = 8, buffer alignment = double word, buffer needs to be a multiple of 8 elements

n −> Minimum buffer size = 32, buffer alignment = word , buffer needs to be a multiple of 16 elements

This function would be named: foo_mM8A8X8_nM32A4X16.

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Texas Instruments TMS320C64X manual Arguments and Conventions Used, 1. Argument Conventions