Moving the Current Read/Write Position Forward - 2023.2 English

AI Engine Kernel and Graph Programming Guide (UG1079)
Document ID
UG1079
Release Date
2023-12-04
Version
2023.2 English

In the following description, input_buffer<TYPE> stands for any of the allowed input buffer port data types. Likewise, output_buffer<TYPE> stands for any of the allowed output buffer port data types.

Table 1. Moving the Current Read/Write Position Forward
Purpose Input Buffer Port Type Output Buffer Port Type
To advance the current read/write position Option 1, Using an iterator:
void simple(input_buffer<TYPE> & in, output_buffer<TYPE> & out)
{
auto pIn  = aie::begin(in);
TYPE data = *pIn++;
...
Option 2, Using the data() API:
void simple_1(input_buffer<TYPE> & in, output_buffer<TYPE> & out)
{
const TYPE* pIn=in.data();
TYPE data = pIn[index++];
...
Option 1, Using an iterator:
void simple(input_buffer<TYPE> & in, output_buffer<TYPE> & out)
{
auto pOut= aie::begin(out);
TYPE data;
*pOut++ = data;
...
Option 2, Using the data() API:
void simple_1(input_buffer<TYPE> & in, output_buffer<TYPE> & out)
{
const TYPE* pOut =(TYPE*)out.data();
pOut[index++] = data;
...
To advance the current read/write position by four times the underlying buffer port type. 
#define VECTOR_SIZE 4
void simple(input_buffer<TYPE> & in, output_buffer<TYPE> & out)
{
auto pIn = aie::begin_vector<VECTOR_SIZE>(in);
v4TYPE data = *pIn++;
...

#define VECTOR_SIZE 4
void simple(input_buffer<TYPE> & in, output_buffer<TYPE> & out)
{
auto pOut  = aie::begin_vector<VECTOR_SIZE>(out);
v4TYPE data;
*pOut++ = data;
...
To advance the current read/write position by eight times the underlying buffer port type. 
#define VECTOR_SIZE 8
void simple(input_buffer<TYPE> & in, output_buffer<TYPE> & out)
{
auto pIn = aie::begin_vector<VECTOR_SIZE>(in);
v8TYPE data = *pIn++;
...

#define VECTOR_SIZE 8
void simple(input_buffer<TYPE> & in, output_buffer<TYPE> & out)
{
auto pOut  = aie::begin_vector<VECTOR_SIZE>(out);
v8TYPE data;
*pOut++ = data;
...