Digital Pre-Distortion

Overview

These are the intrinsics functions used for implementing a DPD forward path. The AI Engine utilizes LUTs to store the products base functions and coefficients. For details in the implementation please read the further application-specific documentation on Digital Pre-distortion on AI Engine.

Typically the DPD forward path comprises the following steps:

• Reading the input streams, splitting the magnitude into idx and frac part and pushing the values into shift registers.
• Loading the values of LUT(idx) and LUT(idx+1) from memory and storing them into data buffer registers.
• Computing the interpolated LUT values while shuffling and post-adding the lanes.
• Move the interpolated LUT values from the accumulator register back to a vector register using the shift-round-saturate (SRS) functionality.
• Multiply the LUT values with the data samples and implement the output delay line functionality in the accumulators.
• Move the results of that operation through the SRS unit to the output stream.

Macros
#define	PMX_CFG(a00, a01, a02, a03, a04, a05, a06, a07, a08, a09, a10, a11, a12, a13, a14, a15)   { a00,a01,a02,a03,a04,a05,(a06)&3,(a06)>>2,a07,a08,a09,a10,a11,(a12)&0xf,(a12)>>4,a13,a14,a15 }
	This MACRO is deprecated and it is defined only for legacy. DPD configuration should be done in user space. This macro was used to create a pmx_cfg struct from the values passed in.

Functions
class	deprecated ("This type is deprecated and it is defined only for legacy. DPD configuration should be done in user space.")]] pmx_idx
	This type is deprecated and it is defined only for legacy. DPD configuration should be done in user space. This macro was used to create a pmx_cfg struct from the values passed in.
v8cacc48	dpd_ipol (v32cint16 xbuf, pmx_idx loffs, pmx_idx roffs, v16int16 zbuf, unsigned int zoffs, unsigned int zoffs_hi, int shft)
	LUT interpolation and post-add intrinsic for 8 complex valued output lanes.
pmx_idx const	set_pmx_idx (pmx_cfg const &pmx)
	Set permutation control for left and right buffer.
void	split (int a, unsigned n, unsigned const w, int &msb, unsigned &lsb)
	Intrinsic used by DPD to split the magnitude into index and fraction for LUT interpolation.
void	split2 (int a, unsigned n, unsigned const w, int &msb_lo, int &msb_hi, unsigned &lsb)
	Similar to doing two separate splits on the lower and upper half of input a.

DPD multiplication intrinsics
v8cacc48	dpd (v8cacc48 acc, int rot, v16cint16 lut, v8cint16 data, unsigned int zoffs)
	Intrinsic multiplying the LUT values with the data values and shifting the outputs through the output delay line.
v8cacc48	dpd (v8cacc48 acc, v4cacc48 scd, int rot, v16cint16 lut, v8cint16 data, unsigned int zoffs)
	Intrinsic multiplying the LUT values with the data values and shifting the outputs through the output delay line.
v8cacc48	dpd (v8cacc48 acc, int rot, v16cint16 lut, v16int16 data, unsigned int zoffs, unsigned int zoffs_hi)
	Intrinsic multiplying the LUT values with the data values and shifting the outputs through the output delay line.
v8cacc48	dpd (v8cacc48 acc, v4cacc48 scd, int rot, v16cint16 lut, v16int16 data, unsigned int zoffs, unsigned int zoffs_hi)
	Intrinsic multiplying the LUT values with the data values and shifting the outputs through the output delay line.
v8cacc48	mac4_preadd_rot (v8cacc48 acc, v4cacc48 scd, int rot, v16cint16 xbuff, int xstart, unsigned int xoffsets, int xstep, int ystart, int ystepmult, v8cint16 zbuff, unsigned int zstart, unsigned int zoffsets, int zstep)
	Multiply-accumulate with pre-adding and accumulator rotation.
v8cacc48	mac4_preadd_rot (v8cacc48 acc, int rot, v16cint16 xbuff, int xstart, unsigned int xoffsets, int xstep, int ystart, int ystepmult, v8cint16 zbuff, unsigned int zstart, unsigned int zoffsets, int zstep)
	Multiply-accumulate with pre-adding and accumulator rotation.
v8cacc48	mac4_preadd_rot (v8cacc48 acc, v4cacc48 scd, int rot, v32cint16 xbuff, int xstart, unsigned int xoffsets, int xstep, int ystart, int ystepmult, v8cint16 zbuff, unsigned int zstart, unsigned int zoffsets, int zstep)
	Multiply-accumulate with pre-adding and accumulator rotation.
v8cacc48	mac4_preadd_rot (v8cacc48 acc, int rot, v32cint16 xbuff, int xstart, unsigned int xoffsets, int xstep, int ystart, int ystepmult, v8cint16 zbuff, unsigned int zstart, unsigned int zoffsets, int zstep)
	Multiply-accumulate with pre-adding and accumulator rotation.
v8cacc48	mac4_rot (v8cacc48 acc, v4cacc48 scd, int rot, v16cint16 xbuff, int xstart, unsigned int xoffsets, int xstep, v8cint16 zbuff, unsigned int zstart, unsigned int zoffsets, int zstep)
	Multiply-accumulate with accumulator rotation.
v8cacc48	mac4_rot (v8cacc48 acc, v4cacc48 scd, int rot, v16cint16 xbuff, int xstart, unsigned int xoffsets, int xstep, v16int16 zbuff, unsigned int zstart, unsigned int zoffsets, int zstep)
	Multiply-accumulate with accumulator rotation.
v8cacc48	mac4_rot (v8cacc48 acc, int rot, v16cint16 xbuff, int xstart, unsigned int xoffsets, int xstep, v8cint16 zbuff, unsigned int zstart, unsigned int zoffsets, int zstep)
	Multiply-accumulate with accumulator rotation.
v8cacc48	mac4_rot (v8cacc48 acc, int rot, v16cint16 xbuff, int xstart, unsigned int xoffsets, int xstep, v16int16 zbuff, unsigned int zstart, unsigned int zoffsets, int zstep)
	Multiply-accumulate with accumulator rotation.
v8cacc48	mac4_rot (v8cacc48 acc, v4cacc48 scd, int rot, v32cint16 xbuff, int xstart, unsigned int xoffsets, int xstep, v8cint16 zbuff, unsigned int zstart, unsigned int zoffsets, int zstep)
	Multiply-accumulate with accumulator rotation.
v8cacc48	mac4_rot (v8cacc48 acc, v4cacc48 scd, int rot, v32cint16 xbuff, int xstart, unsigned int xoffsets, int xstep, v16int16 zbuff, unsigned int zstart, unsigned int zoffsets, int zstep)
	Multiply-accumulate with accumulator rotation.
v8cacc48	mac4_rot (v8cacc48 acc, int rot, v32cint16 xbuff, int xstart, unsigned int xoffsets, int xstep, v8cint16 zbuff, unsigned int zstart, unsigned int zoffsets, int zstep)
	Multiply-accumulate with accumulator rotation.
v8cacc48	mac4_rot (v8cacc48 acc, int rot, v32cint16 xbuff, int xstart, unsigned int xoffsets, int xstep, v16int16 zbuff, unsigned int zstart, unsigned int zoffsets, int zstep)
	Multiply-accumulate with accumulator rotation.

Macro Definition Documentation

#define PMX_CFG	(		a00,
			a01,
			a02,
			a03,
			a04,
			a05,
			a06,
			a07,
			a08,
			a09,
			a10,
			a11,
			a12,
			a13,
			a14,
			a15
	)		{ a00,a01,a02,a03,a04,a05,(a06)&3,(a06)>>2,a07,a08,a09,a10,a11,(a12)&0xf,(a12)>>4,a13,a14,a15 }

This MACRO is deprecated and it is defined only for legacy. DPD configuration should be done in user space. This macro was used to create a pmx_cfg struct from the values passed in.

Function Documentation

union deprecated ( "This type is deprecated and it is defined only for legacy. DPD configuration should be done in user space."  )

readwrite

This type is deprecated and it is defined only for legacy. DPD configuration should be done in user space. This macro was used to create a pmx_cfg struct from the values passed in.

This type is deprecated and it is defined only for legacy. DPD configuration should be done in user space. This type was used internally to the function set_pmx_idx.

This type is deprecated and it is defined only for legacy. DPD configuration should be done in user space. The permuation configuration which was used in setting up the permuation control.

v8cacc48 dpd	(	v8cacc48	acc,
		int	rot,
		v16cint16	lut,
		v8cint16	data,
		unsigned int	zoffs
	)

Intrinsic multiplying the LUT values with the data values and shifting the outputs through the output delay line.

The dpd intrinsic wraps up the DPD. First it permutes the input
data vector to ensure that the correct data values are multiplied
with their corresponding LUT values. Then it executes the 8 complex/complex or 16 complex/real
multiplications. After this, neighbouring values are added in a
post-add step and finally the results are added onto a v8cacc48
delay line which is then shifted by one value. The reason that
the output delay accumulator is 8 values wide is that we want to
output 4 output lanes at a time. Since the highest three entries
in the delay line are intermediate values they are not ready for
output.

The complete operation can be described by the following Pseudo-code:

sum[0] = lut[0]*data[zoffs[0]] + lut[1]*data[zoffs[1]]
sum[1] = lut[2]*data[zoffs[2]] + lut[3]*data[zoffs[3]]
sum[2] = lut[4]*data[zoffs[4]] + lut[5]*data[zoffs[5]]
sum[3] = lut[6]*data[zoffs[6]] + lut[7]*data[zoffs[7]]

v4cacc48 acc_in = null_v4acc48();

//accumulate and rotate
for (auto i = 0;       i < 4; i++)
  acc[i] = acc[i+rot] ;

for (auto i = 4;       i < (8-rot); i++)
  acc[i] = acc[i+rot] + sum[i-4];

for (auto i = (8-rot); i < 8;       i++)
  acc[i] = acc_in[i+rot-8] + sum[i-4] ;

Parameters

acc	Output accumulator which holds the output delay line
rot	Rotation value by which the delay line is shifted. Valid values are 1,2 and 4. This must be a compile time constant.
lut	Vector of 16 complex LUT values to be multiplied with the data values
data	Vector of 8 complex data values
zoffs	Permutation control for the input data values. Each index holds 4bit within this 32bit integer. ##Example## Let us consider the eight complex input terms are ordered in lut as follows: n|Term 1<br>m r|Term 2<br>m r|Lane<br>#|DD<br>m-n :|:-----------:|:-----------:|:-------:|:-------: 0|0 0 |0 2 |0 |0 0|0 1 |0 3 |1 |0 1|1 1 |1 2 |2 |0 1|1 2 |1 4 |3 |0 2|2 2 |2 2 |4 |0 2|2 3 |2 5 |5 |0 3|3 3 |3 2 |6 |0 3|3 4 |3 6 |7 |0 Term 1 and Term 2 denote the two terms that were added into one value by the post-add step during interpolation. One can see that neighbouring pairs share the same n and can therefore be added in the post-adding step. The data delay column tells us which values have to be passed to the zoffs parameter. The function call in this case looks like this:

int const zoffs = 0x00000000;
dpd_result = dpd(dpd_result,get_scd(),1,lut,data,zoffs);

v8cacc48 dpd	(	v8cacc48	acc,
		v4cacc48	scd,
		int	rot,
		v16cint16	lut,
		v8cint16	data,
		unsigned int	zoffs
	)

Intrinsic multiplying the LUT values with the data values and shifting the outputs through the output delay line.

The dpd intrinsic wraps up the DPD. First it permutes the input
data vector to ensure that the correct data values are multiplied
with their corresponding LUT values. Then it executes the 8 complex/complex
multiplications. After this, neighbouring values are added in a
post-add step and finally the results are added onto a v8cacc48
delay line which is then shifted by one value. The reason that
the output delay accumulator is 8 values wide is that we want to
output 4 output lanes at a time. Since the highest three entries
in the delay line are intermediate values they are not ready for
output.

The complete operation can be described by the following Pseudo-code:

sum[0] = lut[0]*data[zoffs[0]] + lut[1]*data[zoffs[1]]
sum[1] = lut[2]*data[zoffs[2]] + lut[3]*data[zoffs[3]]
sum[2] = lut[4]*data[zoffs[4]] + lut[5]*data[zoffs[5]]
sum[3] = lut[6]*data[zoffs[6]] + lut[7]*data[zoffs[7]]

// input from cascade
v4cacc48 acc_in = scd;

//accumulate and rotate
for (auto i = 0;       i < 4; i++)
  acc[i] = acc[i+rot] ;

for (auto i = 4;       i < (8-rot); i++)
  acc[i] = acc[i+rot] + sum[i-4];

for (auto i = (8-rot); i < 8;       i++)
  acc[i] = acc_in[i+rot-8] + sum[i-4] ;

Parameters

acc	Output accumulator which holds the output delay line
scd	Input accumulator from the SCD cascade stream. Optional.
rot	Rotation value by which the delay line is shifted. Valid values are 1,2 and 4. This must be a compile time constant.
lut	Vector of 16 complex LUT values to be multiplied with the data values
data	Vector of 8 complex data values
zoffs	Permutation control for the input data values. Each index holds 4bit within this 32bit integer. ##Example## Let us consider the eight complex input terms are ordered in lut as follows: n|Term 1<br>m r|Term 2<br>m r|Lane<br>#|DD<br>m-n :|:-----------:|:-----------:|:-------:|:-------: 0|0 0 |0 2 |0 |0 0|0 1 |0 3 |1 |0 1|1 1 |1 2 |2 |0 1|1 2 |1 4 |3 |0 2|2 2 |2 2 |4 |0 2|2 3 |2 5 |5 |0 3|3 3 |3 2 |6 |0 3|3 4 |3 6 |7 |0 Term 1 and Term 2 denote the two terms that were added into one value by the post-add step during interpolation. One can see that neighbouring pairs share the same n and can therefore be added in the post-adding step. The data delay column tells us which values have to be passed to the zoffs parameter. The function call in this case looks like this:

int const zoffs = 0x00000000;
dpd_result = dpd(dpd_result,get_scd(),1,lut,data,zoffs);

v8cacc48 dpd	(	v8cacc48	acc,
		int	rot,
		v16cint16	lut,
		v16int16	data,
		unsigned int	zoffs,
		unsigned int	zoffs_hi
	)

Intrinsic multiplying the LUT values with the data values and shifting the outputs through the output delay line.

The dpd intrinsic wraps up the DPD. First it permutes the input
data vector to ensure that the correct data values are multiplied
with their corresponding LUT values. Then it executes the 16 complex/real
multiplications. After this, neighbouring values are added in a
post-add step and finally the results are added onto a v8cacc48
delay line which is then shifted by one value. The reason that
the output delay accumulator is 8 values wide is that we want to
output 4 output lanes at a time. Since the highest three entries
in the delay line are intermediate values they are not ready for
output.

The complete operation can be described by the following Pseudo-code:

sum[0] = lut[0]*data[zoffs[0]] + lut[1]*data[zoffs[1]] + lut[8]*data[zoffs_hi[0]] + lut[9]*data[zoffs_hi[1]]
sum[1] = lut[2]*data[zoffs[2]] + lut[3]*data[zoffs[3]] + lut[10]*data[zoffs_hi[2]] + lut[11]*data[zoffs_hi[3]]
sum[2] = lut[4]*data[zoffs[4]] + lut[5]*data[zoffs[5]] + lut[12]*data[zoffs_hi[4]] + lut[13]*data[zoffs_hi[5]]
sum[3] = lut[6]*data[zoffs[6]] + lut[7]*data[zoffs[7]] + lut[14]*data[zoffs_hi[6]] + lut[15]*data[zoffs_hi[7]]

v4cacc48 acc_in = null_v4acc48();

//accumulate and rotate
for (auto i = 0;       i < 4; i++)
  acc[i] = acc[i+rot] ;

for (auto i = 4;       i < (8-rot); i++)
  acc[i] = acc[i+rot] + sum[i-4];

for (auto i = (8-rot); i < 8;       i++)
  acc[i] = acc_in[i+rot-8] + sum[i-4] ;

Parameters

acc	Output accumulator which holds the output delay line
rot	Rotation value by which the delay line is shifted. Valid values are 1,2 and 4. This must be a compile time constant.
lut	Vector of 16 complex LUT values to be multiplied with the data values
data	Vector of 16 real data values
zoffs	Permutation control for the input data values. Each index holds 4bit within this 32bit integer. Applies to column 0 and 1.
zoffs_hi	Permutation control for the input data values. Each index holds 4bit within this 32bit integer. Applies to column 2 and 3. \endcode

v8cacc48 dpd	(	v8cacc48	acc,
		v4cacc48	scd,
		int	rot,
		v16cint16	lut,
		v16int16	data,
		unsigned int	zoffs,
		unsigned int	zoffs_hi
	)

Intrinsic multiplying the LUT values with the data values and shifting the outputs through the output delay line.

The dpd intrinsic wraps up the DPD. First it permutes the input
data vector to ensure that the correct data values are multiplied
with their corresponding LUT values. Then it executes the 16 complex/real
multiplications. After this, neighbouring values are added in a
post-add step and finally the results are added onto a v8cacc48
delay line which is then shifted by one value. The reason that
the output delay accumulator is 8 values wide is that we want to
output 4 output lanes at a time. Since the highest three entries
in the delay line are intermediate values they are not ready for
output.

The complete operation can be described by the following Pseudo-code:

sum[0] = lut[0]*data[zoffs[0]] + lut[1]*data[zoffs[1]] + lut[8]*data[zoffs_hi[0]] + lut[9]*data[zoffs_hi[1]]
sum[1] = lut[2]*data[zoffs[2]] + lut[3]*data[zoffs[3]] + lut[10]*data[zoffs_hi[2]] + lut[11]*data[zoffs_hi[3]]
sum[2] = lut[4]*data[zoffs[4]] + lut[5]*data[zoffs[5]] + lut[12]*data[zoffs_hi[4]] + lut[13]*data[zoffs_hi[5]]
sum[3] = lut[6]*data[zoffs[6]] + lut[7]*data[zoffs[7]] + lut[14]*data[zoffs_hi[6]] + lut[15]*data[zoffs_hi[7]]

// input from cascade
v4cacc48 acc_in = scd;

//accumulate and rotate
for (auto i = 0;       i < 4; i++)
  acc[i] = acc[i+rot] ;

for (auto i = 4;       i < (8-rot); i++)
  acc[i] = acc[i+rot] + sum[i-4];

for (auto i = (8-rot); i < 8;       i++)
  acc[i] = acc_in[i+rot-8] + sum[i-4] ;

Parameters

acc	Output accumulator which holds the output delay line
scd	Input accumulator from the SCD cascade stream. Optional.
rot	Rotation value by which the delay line is shifted. Valid values are 1,2 and 4. This must be a compile time constant.
lut	Vector of 16 complex LUT values to be multiplied with the data values
data	Vector of 16 real data values
zoffs	Permutation control for the input data values. Each index holds 4bit within this 32bit integer. Applies to column 0 and 1.
zoffs_hi	Permutation control for the input data values. Each index holds 4bit within this 32bit integer. Applies to column 2 and 3. \endcode

v8cacc48 dpd_ipol	(	v32cint16	xbuf,
		pmx_idx	loffs,
		pmx_idx	roffs,
		v16int16	zbuf,
		unsigned int	zoffs,
		unsigned int	zoffs_hi,
		int	shft
	)

LUT interpolation and post-add intrinsic for 8 complex valued output lanes.

The dpd_ipol intrinsic calculates 8 complex values, each one being the sum of two interpolated complex LUT values.
In detail it performs the following operation:

~~~~~~~~
for (i=0; i<16; i++) {
    lbuf(i) = xbuf(loffs(i));
    rbuf(i) = xbuf(roffs(i));
    frac(i) = zbuf((i>8) ? zoffs_hi(i) : zoffs(i));
}

for (i=0; i<8; i++) {
    out(i) = (lbuf(2*i  )<<shift) + (rbuf(2*i  )-lbuf(2*i  ))*frac(2*i  );
    out(i)+= (lbuf(2*i+1)<<shift) + (rbuf(2*i+1)-lbuf(2*i+1))*frac(2*i+1);
}
~~~~~~~~

The following parameters are required by the function:

Parameters

xbuf	Buffer of 32 complex LUT values of type cint16
loffs	Permutation control determining which values end up in lbuf
roffs	Permutation control determining which values end up in rbuf
zbuf	Buffer of 16 real fractional values of type int16
zoffs	Permutation control determining which values end up in frac
zoffs_hi	Permutation control determining which values end up in frac
shift	Value by which the non-multiplied part of the interpolation is shifted in order to compensate for the scaling the happens by multiplying with frac In the first loop a mapping from xbuf to lbuf/rbuf and from zbuf to frac takes place. The user controls the mapping taking place through the four parameters loffs, roffs, zoffs and zoffs_hi. The following criteria must be fulfilled to ensure a correct functionality of the DPD: 1. The pre-adder (rbuf(2*i)-lbuf(2*i) in the code example) subtracts corresponding pairs in the lbuf and rbuf. This means that if a value at a given index in lbuf holds the LUT(idx) value, then the value in rbuf at index i must hold the LUT(idx+1) value. 2. The post-adder (adding up the two values in the second loop) adds neighbouring interpolated values. This means that it has to be ensured that these neighbouring values are meant to be added within the further course of the application. For example in case of a DPD they must have the same m value where (m,r) is the term tuple. 3. If used within a DPD application the next instruction will further reduce the number of values from 8 to four in a post-add step. Again this takes two neighbouring values and adds them together. This has to be taken into consideration at this time as well. They have to belong to the same n value, meaning they have to correspond to the same time in the output delay line. ##DPD Example## Let us assume that we want to call the intrinsic for a DPD with the following terms: r\\m|3|2|1|0 :-:|:|:|:|: 6 |x|-|-|- 5 |x|x|-|- 4 |x|x|x|- 3 |x|x|x|x 2 |-|x|x|x 1 |-|-|x|x 0 |-|-|-|x And the LUT values have been loaded to xbuf in the following pattern: LUT|m|r|Lane<br>idx|Lane<br>idx+1 :-:|:|:|:-------:|:---------: 0 |0|0|0 |4 0 |1|1|1 |5 0 |2|2|2 |6 0 |3|3|3 |7 1 |0|1|8 |12 1 |1|2|9 |13 1 |2|3|10 |14 1 |3|4|11 |15 2 |0|2|16 |20 2 |1|3|17 |21 2 |2|4|18 |22 2 |3|5|19 |23 3 |0|3|24 |28 3 |1|4|25 |29 3 |2|5|26 |30 3 |3|6|27 |31 In order to meet the criteria mentioned above we have to map this to the following pattern in lbuf and rbuf. The PermXX values represent the indices into the old pattern and therefore the values that have to be in the control parameters. n|m|r |Lane|PermIL|PermIR|PermIF :|:|::|:--:|:----:|:----:|:----- 0|0|0 |0 |0 |4 |0 0|0|1 |1 |8 |12 |1 0|0|2 |2 |16 |20 |2 0|0|3 |3 |24 |28 |3 1|1|1 |4 |1 |5 |0 1|1|2 |5 |9 |13 |1 1|1|3 |6 |17 |21 |2 1|1|4 |7 |25 |29 |3 2|2|2 |8 |2 |6 |0 2|2|3 |9 |10 |14 |1 2|2|4 |10 |18 |22 |2 2|2|5 |11 |26 |30 |3 3|3|3 |12 |3 |7 |0 3|3|4 |13 |11 |15 |1 3|3|5 |14 |19 |23 |2 3|3|6 |15 |27 |31 |3 Therefore one can prepare the permutation configuration using the following structure and call the intrinsic: ~~~~~~~~ pmx_cfg left = PMX_CFG ( 0, 8,16,24, 1, 9,17,25, 2,10,18,26, 3,11,19,27); pmx_cfg right = PMX_CFG ( 4,12,20,28, 5,13,21,29, 6,14,22,30, 7,15,23,31); unsigned int zoffs = 0x32103210; unsigned int zoffs_hi = 0x32103210; v8cacc48 ipol_result = dpd_ipol(lut, set_pmx_idx(left), set_pmx_idx(right), frac, zoffs, zoffs_hi, mag_scale); ~~~~~~~~

v8cacc48 mac4_preadd_rot	(	v8cacc48	acc,
		v4cacc48	scd,
		int	rot,
		v16cint16	xbuff,
		int	xstart,
		unsigned int	xoffsets,
		int	xstep,
		int	ystart,
		int	ystepmult,
		v8cint16	zbuff,
		unsigned int	zstart,
		unsigned int	zoffsets,
		int	zstep
	)

Multiply-accumulate with pre-adding and accumulator rotation.

// rotate accumulator and shift in values from scd
v8cacc48 acc_tmp = acc[rot:7]::scd[0:rot-1];

acc_tmp[4] += (xbuff[xstart+xoffsets[0]      ] + xbuff[ystart+xoffsets[0]                ]) * zbuf[zstart+zoffsets[0]      ]
           +  (xbuff[xstart+xoffsets[0]+xstep] + xbuff[ystart+xoffsets[0]+xstep*ystepmult]) * zbuf[zstart+zoffsets[0]+zstep]
acc_tmp[5] += (xbuff[xstart+xoffsets[1]      ] + xbuff[ystart+xoffsets[1]                ]) * zbuf[zstart+zoffsets[1]      ]
           +  (xbuff[xstart+xoffsets[1]+xstep] + xbuff[ystart+xoffsets[1]+xstep*ystepmult]) * zbuf[zstart+zoffsets[1]+zstep]
acc_tmp[6] += (xbuff[xstart+xoffsets[2]      ] + xbuff[ystart+xoffsets[2]                ]) * zbuf[zstart+zoffsets[2]      ]
           +  (xbuff[xstart+xoffsets[2]+xstep] + xbuff[ystart+xoffsets[2]+xstep*ystepmult]) * zbuf[zstart+zoffsets[2]+zstep]
acc_tmp[7] += (xbuff[xstart+xoffsets[3]      ] + xbuff[ystart+xoffsets[3]                ]) * zbuf[zstart+zoffsets[3]      ]
           +  (xbuff[xstart+xoffsets[3]+xstep] + xbuff[ystart+xoffsets[3]+xstep*ystepmult]) * zbuf[zstart+zoffsets[3]+zstep]

return acc_tmp

Parameters

[in]	acc	Previous accumulator
[in]	scd	Vector to be "shifted in". This must come from a call to get_scd()
[in]	rot	Number of lanes to be rotated. Can be 1, 2 or 4. Must be a compile time constant
[in]	xbuff	Data buffer for first multiplier input (LUT terms in the DPD context)
[in]	xstart	Start index in xbuff for first pre-addition summand
[in]	xoffsets	Row-dependent offsets in xbuff for first pre-addition summand
[in]	xstep	Offset between columns for xbuff for first pre-addition summand
[in]	ystart	Start index in xbuff for second pre-addition summand
[in]	ystepmult	Column offset multiplier in xbuff for second pre-addition summand. Can be 0, 1, 2, 4, 8, -1, -2 or -4. Must be a compile time constant
[in]	zbuff	Data buffer for second multiplier input (data values in the DPD context)
[in]	zstart	Start index in zbuff. Must be a compile time constant
[in]	zoffsets	Row-dependent offsets in zbuff
[in]	zstep	Offset between columns for zbuff

v8cacc48 mac4_preadd_rot	(	v8cacc48	acc,
		int	rot,
		v16cint16	xbuff,
		int	xstart,
		unsigned int	xoffsets,
		int	xstep,
		int	ystart,
		int	ystepmult,
		v8cint16	zbuff,
		unsigned int	zstart,
		unsigned int	zoffsets,
		int	zstep
	)

Multiply-accumulate with pre-adding and accumulator rotation.

// rotate accumulator and shift in zeros
v8cacc48 acc_tmp = acc[rot:7]::zeros(rot,1);

acc_tmp[4] += (xbuff[xstart+xoffsets[0]      ] + xbuff[ystart+xoffsets[0]                ]) * zbuf[zstart+zoffsets[0]      ]
           +  (xbuff[xstart+xoffsets[0]+xstep] + xbuff[ystart+xoffsets[0]+xstep*ystepmult]) * zbuf[zstart+zoffsets[0]+zstep]
acc_tmp[5] += (xbuff[xstart+xoffsets[1]      ] + xbuff[ystart+xoffsets[1]                ]) * zbuf[zstart+zoffsets[1]      ]
           +  (xbuff[xstart+xoffsets[1]+xstep] + xbuff[ystart+xoffsets[1]+xstep*ystepmult]) * zbuf[zstart+zoffsets[1]+zstep]
acc_tmp[6] += (xbuff[xstart+xoffsets[2]      ] + xbuff[ystart+xoffsets[2]                ]) * zbuf[zstart+zoffsets[2]      ]
           +  (xbuff[xstart+xoffsets[2]+xstep] + xbuff[ystart+xoffsets[2]+xstep*ystepmult]) * zbuf[zstart+zoffsets[2]+zstep]
acc_tmp[7] += (xbuff[xstart+xoffsets[3]      ] + xbuff[ystart+xoffsets[3]                ]) * zbuf[zstart+zoffsets[3]      ]
           +  (xbuff[xstart+xoffsets[3]+xstep] + xbuff[ystart+xoffsets[3]+xstep*ystepmult]) * zbuf[zstart+zoffsets[3]+zstep]

return acc_tmp

Parameters

[in]	acc	Previous accumulator
[in]	rot	Number of lanes to be rotated. Can be 1, 2 or 4. Must be a compile time constant
[in]	xbuff	Data buffer for first multiplier input (LUT terms in the DPD context)
[in]	xstart	Start index in xbuff for first pre-addition summand
[in]	xoffsets	Row-dependent offsets in xbuff for first pre-addition summand
[in]	xstep	Offset between columns for xbuff for first pre-addition summand
[in]	ystart	Start index in xbuff for second pre-addition summand
[in]	ystepmult	Column offset multiplier in xbuff for second pre-addition summand. Can be 0, 1, 2, 4, 8, -1, -2 or -4. Must be a compile time constant
[in]	zbuff	Data buffer for second multiplier input (data values in the DPD context)
[in]	zstart	Start index in zbuff. Must be a compile time constant
[in]	zoffsets	Row-dependent offsets in zbuff
[in]	zstep	Offset between columns for zbuff

v8cacc48 mac4_preadd_rot	(	v8cacc48	acc,
		v4cacc48	scd,
		int	rot,
		v32cint16	xbuff,
		int	xstart,
		unsigned int	xoffsets,
		int	xstep,
		int	ystart,
		int	ystepmult,
		v8cint16	zbuff,
		unsigned int	zstart,
		unsigned int	zoffsets,
		int	zstep
	)

Multiply-accumulate with pre-adding and accumulator rotation.

// rotate accumulator and shift in values from scd
v8cacc48 acc_tmp = acc[rot:7]::scd[0:rot-1];

acc_tmp[4] += (xbuff[xstart+xoffsets[0]      ] + xbuff[ystart+xoffsets[0]                ]) * zbuf[zstart+zoffsets[0]      ]
           +  (xbuff[xstart+xoffsets[0]+xstep] + xbuff[ystart+xoffsets[0]+xstep*ystepmult]) * zbuf[zstart+zoffsets[0]+zstep]
acc_tmp[5] += (xbuff[xstart+xoffsets[1]      ] + xbuff[ystart+xoffsets[1]                ]) * zbuf[zstart+zoffsets[1]      ]
           +  (xbuff[xstart+xoffsets[1]+xstep] + xbuff[ystart+xoffsets[1]+xstep*ystepmult]) * zbuf[zstart+zoffsets[1]+zstep]
acc_tmp[6] += (xbuff[xstart+xoffsets[2]      ] + xbuff[ystart+xoffsets[2]                ]) * zbuf[zstart+zoffsets[2]      ]
           +  (xbuff[xstart+xoffsets[2]+xstep] + xbuff[ystart+xoffsets[2]+xstep*ystepmult]) * zbuf[zstart+zoffsets[2]+zstep]
acc_tmp[7] += (xbuff[xstart+xoffsets[3]      ] + xbuff[ystart+xoffsets[3]                ]) * zbuf[zstart+zoffsets[3]      ]
           +  (xbuff[xstart+xoffsets[3]+xstep] + xbuff[ystart+xoffsets[3]+xstep*ystepmult]) * zbuf[zstart+zoffsets[3]+zstep]

return acc_tmp

Parameters

[in]	acc	Previous accumulator
[in]	scd	Vector to be "shifted in". This must come from a call to get_scd()
[in]	rot	Number of lanes to be rotated. Can be 1, 2 or 4. Must be a compile time constant
[in]	xbuff	Data buffer for first multiplier input (LUT terms in the DPD context)
[in]	xstart	Start index in xbuff for first pre-addition summand
[in]	xoffsets	Row-dependent offsets in xbuff for first pre-addition summand
[in]	xstep	Offset between columns for xbuff for first pre-addition summand
[in]	ystart	Start index in xbuff for second pre-addition summand
[in]	ystepmult	Column offset multiplier in xbuff for second pre-addition summand. Can be 0, 1, 2, 4, 8, -1, -2 or -4. Must be a compile time constant
[in]	zbuff	Data buffer for second multiplier input (data values in the DPD context)
[in]	zstart	Start index in zbuff. Must be a compile time constant
[in]	zoffsets	Row-dependent offsets in zbuff
[in]	zstep	Offset between columns for zbuff

v8cacc48 mac4_preadd_rot	(	v8cacc48	acc,
		int	rot,
		v32cint16	xbuff,
		int	xstart,
		unsigned int	xoffsets,
		int	xstep,
		int	ystart,
		int	ystepmult,
		v8cint16	zbuff,
		unsigned int	zstart,
		unsigned int	zoffsets,
		int	zstep
	)

Multiply-accumulate with pre-adding and accumulator rotation.

// rotate accumulator and shift in zeros
v8cacc48 acc_tmp = acc[rot:7]::zeros(rot,1);

acc_tmp[4] += (xbuff[xstart+xoffsets[0]      ] + xbuff[ystart+xoffsets[0]                ]) * zbuf[zstart+zoffsets[0]      ]
           +  (xbuff[xstart+xoffsets[0]+xstep] + xbuff[ystart+xoffsets[0]+xstep*ystepmult]) * zbuf[zstart+zoffsets[0]+zstep]
acc_tmp[5] += (xbuff[xstart+xoffsets[1]      ] + xbuff[ystart+xoffsets[1]                ]) * zbuf[zstart+zoffsets[1]      ]
           +  (xbuff[xstart+xoffsets[1]+xstep] + xbuff[ystart+xoffsets[1]+xstep*ystepmult]) * zbuf[zstart+zoffsets[1]+zstep]
acc_tmp[6] += (xbuff[xstart+xoffsets[2]      ] + xbuff[ystart+xoffsets[2]                ]) * zbuf[zstart+zoffsets[2]      ]
           +  (xbuff[xstart+xoffsets[2]+xstep] + xbuff[ystart+xoffsets[2]+xstep*ystepmult]) * zbuf[zstart+zoffsets[2]+zstep]
acc_tmp[7] += (xbuff[xstart+xoffsets[3]      ] + xbuff[ystart+xoffsets[3]                ]) * zbuf[zstart+zoffsets[3]      ]
           +  (xbuff[xstart+xoffsets[3]+xstep] + xbuff[ystart+xoffsets[3]+xstep*ystepmult]) * zbuf[zstart+zoffsets[3]+zstep]

return acc_tmp

Parameters

[in]	acc	Previous accumulator
[in]	rot	Number of lanes to be rotated. Can be 1, 2 or 4. Must be a compile time constant
[in]	xbuff	Data buffer for first multiplier input (LUT terms in the DPD context)
[in]	xstart	Start index in xbuff for first pre-addition summand
[in]	xoffsets	Row-dependent offsets in xbuff for first pre-addition summand
[in]	xstep	Offset between columns for xbuff for first pre-addition summand
[in]	ystart	Start index in xbuff for second pre-addition summand
[in]	ystepmult	Column offset multiplier in xbuff for second pre-addition summand. Can be 0, 1, 2, 4, 8, -1, -2 or -4. Must be a compile time constant
[in]	zbuff	Data buffer for second multiplier input (data values in the DPD context)
[in]	zstart	Start index in zbuff. Must be a compile time constant
[in]	zoffsets	Row-dependent offsets in zbuff
[in]	zstep	Offset between columns for zbuff

v8cacc48 mac4_rot	(	v8cacc48	acc,
		v4cacc48	scd,
		int	rot,
		v16cint16	xbuff,
		int	xstart,
		unsigned int	xoffsets,
		int	xstep,
		v8cint16	zbuff,
		unsigned int	zstart,
		unsigned int	zoffsets,
		int	zstep
	)

Multiply-accumulate with accumulator rotation.

// rotate accumulator and shift in values from scd
v8cacc48 acc_tmp = acc[rot:7]::scd[0:rot-1];

acc_tmp[4] += xbuff[xstart+xoffsets[0]] * zbuf[zstart+zoffsets[0]] + xbuff[xstart+xoffsets[0]+xstep] * zbuf[zstart+zoffsets[0]+zstep]
acc_tmp[5] += xbuff[xstart+xoffsets[1]] * zbuf[zstart+zoffsets[1]] + xbuff[xstart+xoffsets[1]+xstep] * zbuf[zstart+zoffsets[1]+zstep]
acc_tmp[6] += xbuff[xstart+xoffsets[2]] * zbuf[zstart+zoffsets[2]] + xbuff[xstart+xoffsets[2]+xstep] * zbuf[zstart+zoffsets[2]+zstep]
acc_tmp[7] += xbuff[xstart+xoffsets[3]] * zbuf[zstart+zoffsets[3]] + xbuff[xstart+xoffsets[3]+xstep] * zbuf[zstart+zoffsets[3]+zstep]

return acc_tmp

Parameters

[in]	acc	Previous accumulator
[in]	scd	Vector to be "shifted in". This must come from a call to get_scd()
[in]	rot	Number of lanes to be rotated. Can be 1, 2 or 4. Must be a compile time constant
[in]	xbuff	Data buffer for first multiplier input (LUT terms in the DPD context)
[in]	xstart	Start index in xbuff
[in]	xoffsets	Row-dependent offsets in xbuff
[in]	xstep	Offset between columns for xbuff
[in]	zbuff	Data buffer for second multiplier input (data values in the DPD context)
[in]	zstart	Start index in zbuff. Must be a compile time constant
[in]	zoffsets	Row-dependent offsets in zbuff
[in]	zstep	Offset between columns for zbuff

v8cacc48 mac4_rot	(	v8cacc48	acc,
		v4cacc48	scd,
		int	rot,
		v16cint16	xbuff,
		int	xstart,
		unsigned int	xoffsets,
		int	xstep,
		v16int16	zbuff,
		unsigned int	zstart,
		unsigned int	zoffsets,
		int	zstep
	)

Multiply-accumulate with accumulator rotation.

// rotate accumulator and shift in values from scd
v8cacc48 acc_tmp = acc[rot:7]::scd[0:rot-1];

acc_tmp[4] += xbuff[xstart+xoffsets[0]] * zbuf[zstart+zoffsets[0]] + xbuff[xstart+xoffsets[0]+xstep] * zbuf[zstart+zoffsets[0]+zstep] + xbuff[xstart + xoffset[0] + 2*xstep] * zbuff[zstart + zoffset[0] + 2*zstep] + xbuff[xstart + xoffset[0] + 3*xstep] * zbuff[zstart + zoffset[0] + 3*zstep]
acc_tmp[5] += xbuff[xstart+xoffsets[1]] * zbuf[zstart+zoffsets[1]] + xbuff[xstart+xoffsets[1]+xstep] * zbuf[zstart+zoffsets[1]+zstep] + xbuff[xstart + xoffset[1] + 2*xstep] * zbuff[zstart + zoffset[1] + 2*zstep] + xbuff[xstart + xoffset[1] + 3*xstep] * zbuff[zstart + zoffset[1] + 3*zstep]
acc_tmp[6] += xbuff[xstart+xoffsets[2]] * zbuf[zstart+zoffsets[2]] + xbuff[xstart+xoffsets[2]+xstep] * zbuf[zstart+zoffsets[2]+zstep] + xbuff[xstart + xoffset[2] + 2*xstep] * zbuff[zstart + zoffset[2] + 2*zstep] + xbuff[xstart + xoffset[2] + 3*xstep] * zbuff[zstart + zoffset[2] + 3*zstep]
acc_tmp[7] += xbuff[xstart+xoffsets[3]] * zbuf[zstart+zoffsets[3]] + xbuff[xstart+xoffsets[3]+xstep] * zbuf[zstart+zoffsets[3]+zstep] + xbuff[xstart + xoffset[3] + 2*xstep] * zbuff[zstart + zoffset[3] + 2*zstep] + xbuff[xstart + xoffset[3] + 3*xstep] * zbuff[zstart + zoffset[3] + 3*zstep]


return acc_tmp

Parameters

[in]	acc	Previous accumulator
[in]	scd	Vector to be "shifted in". This must come from a call to get_scd()
[in]	rot	Number of lanes to be rotated. Can be 1, 2 or 4. Must be a compile time constant
[in]	xbuff	Data buffer for first multiplier input (LUT terms in the DPD context)
[in]	xstart	Start index in xbuff
[in]	xoffsets	Row-dependent offsets in xbuff
[in]	xstep	Offset between columns for xbuff
[in]	zbuff	Data buffer for second multiplier input (data values in the DPD context)
[in]	zstart	Start index in zbuff. Must be a compile time constant
[in]	zoffsets	Row-dependent offsets in zbuff
[in]	zstep	Offset between columns for zbuff

v8cacc48 mac4_rot	(	v8cacc48	acc,
		int	rot,
		v16cint16	xbuff,
		int	xstart,
		unsigned int	xoffsets,
		int	xstep,
		v8cint16	zbuff,
		unsigned int	zstart,
		unsigned int	zoffsets,
		int	zstep
	)

Multiply-accumulate with accumulator rotation.

// rotate accumulator and shift in zeros
v8cacc48 acc_tmp = acc[rot:7]::zeros(rot,1);

acc_tmp[4] += xbuff[xstart+xoffsets[0]] * zbuf[zstart+zoffsets[0]] + xbuff[xstart+xoffsets[0]+xstep] * zbuf[zstart+zoffsets[0]+zstep]
acc_tmp[5] += xbuff[xstart+xoffsets[1]] * zbuf[zstart+zoffsets[1]] + xbuff[xstart+xoffsets[1]+xstep] * zbuf[zstart+zoffsets[1]+zstep]
acc_tmp[6] += xbuff[xstart+xoffsets[2]] * zbuf[zstart+zoffsets[2]] + xbuff[xstart+xoffsets[2]+xstep] * zbuf[zstart+zoffsets[2]+zstep]
acc_tmp[7] += xbuff[xstart+xoffsets[3]] * zbuf[zstart+zoffsets[3]] + xbuff[xstart+xoffsets[3]+xstep] * zbuf[zstart+zoffsets[3]+zstep]
return acc_tmp

Parameters

[in]	acc	Previous accumulator
[in]	rot	Number of lanes to be rotated. Can be 1, 2 or 4. Must be a compile time constant
[in]	xbuff	Data buffer for first multiplier input (LUT terms in the DPD context)
[in]	xstart	Start index in xbuff for first pre-addition summand
[in]	xoffsets	Row-dependent offsets in xbuff
[in]	xstep	Offset between columns for xbuff
[in]	zbuff	Data buffer for second multiplier input (data values in the DPD context)
[in]	zstart	Start index in zbuff. Must be a compile time constant
[in]	zoffsets	Row-dependent offsets in zbuff
[in]	zstep	Offset between columns for zbuff

v8cacc48 mac4_rot	(	v8cacc48	acc,
		int	rot,
		v16cint16	xbuff,
		int	xstart,
		unsigned int	xoffsets,
		int	xstep,
		v16int16	zbuff,
		unsigned int	zstart,
		unsigned int	zoffsets,
		int	zstep
	)

Multiply-accumulate with accumulator rotation.

// rotate accumulator and shift in zeros
v8cacc48 acc_tmp = acc[rot:7]::zeros(rot,1);

acc_tmp[4] += xbuff[xstart+xoffsets[0]] * zbuf[zstart+zoffsets[0]] + xbuff[xstart+xoffsets[0]+xstep] * zbuf[zstart+zoffsets[0]+zstep] + xbuff[xstart + xoffset[0] + 2*xstep] * zbuff[zstart + zoffset[0] + 2*zstep] + xbuff[xstart + xoffset[0] + 3*xstep] * zbuff[zstart + zoffset[0] + 3*zstep]
acc_tmp[5] += xbuff[xstart+xoffsets[1]] * zbuf[zstart+zoffsets[1]] + xbuff[xstart+xoffsets[1]+xstep] * zbuf[zstart+zoffsets[1]+zstep] + xbuff[xstart + xoffset[1] + 2*xstep] * zbuff[zstart + zoffset[1] + 2*zstep] + xbuff[xstart + xoffset[1] + 3*xstep] * zbuff[zstart + zoffset[1] + 3*zstep]
acc_tmp[6] += xbuff[xstart+xoffsets[2]] * zbuf[zstart+zoffsets[2]] + xbuff[xstart+xoffsets[2]+xstep] * zbuf[zstart+zoffsets[2]+zstep] + xbuff[xstart + xoffset[2] + 2*xstep] * zbuff[zstart + zoffset[2] + 2*zstep] + xbuff[xstart + xoffset[2] + 3*xstep] * zbuff[zstart + zoffset[2] + 3*zstep]
acc_tmp[7] += xbuff[xstart+xoffsets[3]] * zbuf[zstart+zoffsets[3]] + xbuff[xstart+xoffsets[3]+xstep] * zbuf[zstart+zoffsets[3]+zstep] + xbuff[xstart + xoffset[3] + 2*xstep] * zbuff[zstart + zoffset[3] + 2*zstep] + xbuff[xstart + xoffset[3] + 3*xstep] * zbuff[zstart + zoffset[3] + 3*zstep]

return acc_tmp

Parameters

[in]	acc	Previous accumulator
[in]	rot	Number of lanes to be rotated. Can be 1, 2 or 4. Must be a compile time constant
[in]	xbuff	Data buffer for first multiplier input (LUT terms in the DPD context)
[in]	xstart	Start index in xbuff for first pre-addition summand
[in]	xoffsets	Row-dependent offsets in xbuff
[in]	xstep	Offset between columns for xbuff
[in]	zbuff	Data buffer for second multiplier input (data values in the DPD context)
[in]	zstart	Start index in zbuff. Must be a compile time constant
[in]	zoffsets	Row-dependent offsets in zbuff
[in]	zstep	Offset between columns for zbuff

v8cacc48 mac4_rot	(	v8cacc48	acc,
		v4cacc48	scd,
		int	rot,
		v32cint16	xbuff,
		int	xstart,
		unsigned int	xoffsets,
		int	xstep,
		v8cint16	zbuff,
		unsigned int	zstart,
		unsigned int	zoffsets,
		int	zstep
	)

Multiply-accumulate with accumulator rotation.

// rotate accumulator and shift in values from scd
v8cacc48 acc_tmp = acc[rot:7]::scd[0:rot-1];

acc_tmp[4] += xbuff[xstart+xoffsets[0]] * zbuf[zstart+zoffsets[0]] + xbuff[xstart+xoffsets[0]+xstep] * zbuf[zstart+zoffsets[0]+zstep]
acc_tmp[5] += xbuff[xstart+xoffsets[1]] * zbuf[zstart+zoffsets[1]] + xbuff[xstart+xoffsets[1]+xstep] * zbuf[zstart+zoffsets[1]+zstep]
acc_tmp[6] += xbuff[xstart+xoffsets[2]] * zbuf[zstart+zoffsets[2]] + xbuff[xstart+xoffsets[2]+xstep] * zbuf[zstart+zoffsets[2]+zstep]
acc_tmp[7] += xbuff[xstart+xoffsets[3]] * zbuf[zstart+zoffsets[3]] + xbuff[xstart+xoffsets[3]+xstep] * zbuf[zstart+zoffsets[3]+zstep]

return acc_tmp

Parameters

[in]	acc	Previous accumulator
[in]	scd	Vector to be "shifted in". This must come from a call to get_scd()
[in]	rot	Number of lanes to be rotated. Can be 1, 2 or 4. Must be a compile time constant
[in]	xbuff	Data buffer for first multiplier input (LUT terms in the DPD context)
[in]	xstart	Start index in xbuff for first pre-addition summand
[in]	xoffsets	Row-dependent offsets in xbuff
[in]	xstep	Offset between columns for xbuff
[in]	zbuff	Data buffer for second multiplier input (data values in the DPD context)
[in]	zstart	Start index in zbuff. Must be a compile time constant
[in]	zoffsets	Row-dependent offsets in zbuff
[in]	zstep	Offset between columns for zbuff

v8cacc48 mac4_rot	(	v8cacc48	acc,
		v4cacc48	scd,
		int	rot,
		v32cint16	xbuff,
		int	xstart,
		unsigned int	xoffsets,
		int	xstep,
		v16int16	zbuff,
		unsigned int	zstart,
		unsigned int	zoffsets,
		int	zstep
	)

Multiply-accumulate with accumulator rotation.

// rotate accumulator and shift in values from scd
v8cacc48 acc_tmp = acc[rot:7]::scd[0:rot-1];

acc_tmp[4] += xbuff[xstart+xoffsets[0]] * zbuf[zstart+zoffsets[0]] + xbuff[xstart+xoffsets[0]+xstep] * zbuf[zstart+zoffsets[0]+zstep] + xbuff[xstart + xoffset[0] + 2*xstep] * zbuff[zstart + zoffset[0] + 2*zstep] + xbuff[xstart + xoffset[0] + 3*xstep] * zbuff[zstart + zoffset[0] + 3*zstep]
acc_tmp[5] += xbuff[xstart+xoffsets[1]] * zbuf[zstart+zoffsets[1]] + xbuff[xstart+xoffsets[1]+xstep] * zbuf[zstart+zoffsets[1]+zstep] + xbuff[xstart + xoffset[1] + 2*xstep] * zbuff[zstart + zoffset[1] + 2*zstep] + xbuff[xstart + xoffset[1] + 3*xstep] * zbuff[zstart + zoffset[1] + 3*zstep]
acc_tmp[6] += xbuff[xstart+xoffsets[2]] * zbuf[zstart+zoffsets[2]] + xbuff[xstart+xoffsets[2]+xstep] * zbuf[zstart+zoffsets[2]+zstep] + xbuff[xstart + xoffset[2] + 2*xstep] * zbuff[zstart + zoffset[2] + 2*zstep] + xbuff[xstart + xoffset[2] + 3*xstep] * zbuff[zstart + zoffset[2] + 3*zstep]
acc_tmp[7] += xbuff[xstart+xoffsets[3]] * zbuf[zstart+zoffsets[3]] + xbuff[xstart+xoffsets[3]+xstep] * zbuf[zstart+zoffsets[3]+zstep] + xbuff[xstart + xoffset[3] + 2*xstep] * zbuff[zstart + zoffset[3] + 2*zstep] + xbuff[xstart + xoffset[3] + 3*xstep] * zbuff[zstart + zoffset[3] + 3*zstep]

return acc_tmp

Parameters

[in]	acc	Previous accumulator
[in]	scd	Vector to be "shifted in". This must come from a call to get_scd()
[in]	rot	Number of lanes to be rotated. Can be 1, 2 or 4. Must be a compile time constant
[in]	xbuff	Data buffer for first multiplier input (LUT terms in the DPD context)
[in]	xstart	Start index in xbuff for first pre-addition summand
[in]	xoffsets	Row-dependent offsets in xbuff
[in]	xstep	Offset between columns for xbuff
[in]	zbuff	Data buffer for second multiplier input (data values in the DPD context)
[in]	zstart	Start index in zbuff. Must be a compile time constant
[in]	zoffsets	Row-dependent offsets in zbuff
[in]	zstep	Offset between columns for zbuff

v8cacc48 mac4_rot	(	v8cacc48	acc,
		int	rot,
		v32cint16	xbuff,
		int	xstart,
		unsigned int	xoffsets,
		int	xstep,
		v8cint16	zbuff,
		unsigned int	zstart,
		unsigned int	zoffsets,
		int	zstep
	)

Multiply-accumulate with accumulator rotation.

// rotate accumulator and shift in zeros
v8cacc48 acc_tmp = acc[rot:7]::zeros(rot,1);

acc_tmp[4] += xbuff[xstart+xoffsets[0]] * zbuf[zstart+zoffsets[0]] + xbuff[xstart+xoffsets[0]+xstep] * zbuf[zstart+zoffsets[0]+zstep]
acc_tmp[5] += xbuff[xstart+xoffsets[1]] * zbuf[zstart+zoffsets[1]] + xbuff[xstart+xoffsets[1]+xstep] * zbuf[zstart+zoffsets[1]+zstep]
acc_tmp[6] += xbuff[xstart+xoffsets[2]] * zbuf[zstart+zoffsets[2]] + xbuff[xstart+xoffsets[2]+xstep] * zbuf[zstart+zoffsets[2]+zstep]
acc_tmp[7] += xbuff[xstart+xoffsets[3]] * zbuf[zstart+zoffsets[3]] + xbuff[xstart+xoffsets[3]+xstep] * zbuf[zstart+zoffsets[3]+zstep]

return acc_tmp

Parameters

[in]	acc	Previous accumulator
[in]	rot	Number of lanes to be rotated. Can be 1, 2 or 4. Must be a compile time constant
[in]	xbuff	Data buffer for first multiplier input (LUT terms in the DPD context)
[in]	xstart	Start index in xbuff for first pre-addition summand
[in]	xoffsets	Row-dependent offsets in xbuff
[in]	xstep	Offset between columns for xbuff
[in]	zbuff	Data buffer for second multiplier input (data values in the DPD context)
[in]	zstart	Start index in zbuff. Must be a compile time constant
[in]	zoffsets	Row-dependent offsets in zbuff
[in]	zstep	Offset between columns for zbuff

v8cacc48 mac4_rot	(	v8cacc48	acc,
		int	rot,
		v32cint16	xbuff,
		int	xstart,
		unsigned int	xoffsets,
		int	xstep,
		v16int16	zbuff,
		unsigned int	zstart,
		unsigned int	zoffsets,
		int	zstep
	)

Multiply-accumulate with accumulator rotation.

// rotate accumulator and shift in zeros
v8cacc48 acc_tmp = acc[rot:7]::zeros(rot,1);


acc_tmp[4] += xbuff[xstart+xoffsets[0]] * zbuf[zstart+zoffsets[0]] + xbuff[xstart+xoffsets[0]+xstep] * zbuf[zstart+zoffsets[0]+zstep] + xbuff[xstart + xoffset[0] + 2*xstep] * zbuff[zstart + zoffset[0] + 2*zstep] + xbuff[xstart + xoffset[0] + 3*xstep] * zbuff[zstart + zoffset[0] + 3*zstep]
acc_tmp[5] += xbuff[xstart+xoffsets[1]] * zbuf[zstart+zoffsets[1]] + xbuff[xstart+xoffsets[1]+xstep] * zbuf[zstart+zoffsets[1]+zstep] + xbuff[xstart + xoffset[1] + 2*xstep] * zbuff[zstart + zoffset[1] + 2*zstep] + xbuff[xstart + xoffset[1] + 3*xstep] * zbuff[zstart + zoffset[1] + 3*zstep]
acc_tmp[6] += xbuff[xstart+xoffsets[2]] * zbuf[zstart+zoffsets[2]] + xbuff[xstart+xoffsets[2]+xstep] * zbuf[zstart+zoffsets[2]+zstep] + xbuff[xstart + xoffset[2] + 2*xstep] * zbuff[zstart + zoffset[2] + 2*zstep] + xbuff[xstart + xoffset[2] + 3*xstep] * zbuff[zstart + zoffset[2] + 3*zstep]
acc_tmp[7] += xbuff[xstart+xoffsets[3]] * zbuf[zstart+zoffsets[3]] + xbuff[xstart+xoffsets[3]+xstep] * zbuf[zstart+zoffsets[3]+zstep] + xbuff[xstart + xoffset[3] + 2*xstep] * zbuff[zstart + zoffset[3] + 2*zstep] + xbuff[xstart + xoffset[3] + 3*xstep] * zbuff[zstart + zoffset[3] + 3*zstep]

return acc_tmp

Parameters

[in]	acc	Previous accumulator
[in]	rot	Number of lanes to be rotated. Can be 1, 2 or 4. Must be a compile time constant
[in]	xbuff	Data buffer for first multiplier input (LUT terms in the DPD context)
[in]	xstart	Start index in xbuff for first pre-addition summand
[in]	xoffsets	Row-dependent offsets in xbuff
[in]	xstep	Offset between columns for xbuff
[in]	zbuff	Data buffer for second multiplier input (data values in the DPD context)
[in]	zstart	Start index in zbuff. Must be a compile time constant
[in]	zoffsets	Row-dependent offsets in zbuff
[in]	zstep	Offset between columns for zbuff

pmx_idx const set_pmx_idx

(

pmx_cfg const &

pmx

)

Set permutation control for left and right buffer.

This intrinsic is used in DPD to set the permutation control for left and right buffer. Is is composed of 16 5-bit values.

void split	(	int	a,
		unsigned	n,
		unsigned const	w,
		int &	msb,
		unsigned &	lsb
	)

Intrinsic used by DPD to split the magnitude into index and fraction for LUT interpolation.

The split intrinsic prepares the magnitude values for further processing in the DPD. The parameters are the following:

Parameters

a	Input magnitude as a 32bit integer
n	Number of LSBs that shall end up in the fraction. This must be a compile time constant.
w	Width of the LUT in bytes on a binary logarithmic scale. The index will be shifted to the left by this value. This must be a compile-time constant.
msb	Output index into the LUT by reference
lsb	Output fraction for interpolation between msb and msb+1 in the LUT by reference

The instrinsic performs the following operation:

msb  = (a >> n) << w;
lsb = a & ((1 << n) – 1);

To compute the index into the LUT the intrinsic first shifts the magnitude value to the right by n and then to the left by w, therefore disregarding the fractional bits and filling up as many zeroes as necessary to correctly index the LUT. For the fraction value the magnitude is masked so that only the fractional bits remain.

Example

Let us assume we want to split a magnitude value under the following requirements:

1. Each LUT entry contains four cint16 values.
2. We want to interpolate with a 7bit fractional value.

The first requirement dictates that w must be ld(4*sizeof(cint16)) = ld(16) = 4. n obviously is 7.

Therefore in this case a call of the split function could look like this:

split(a,7,4,msb,lsb);

void split2	(	int	a,
		unsigned	n,
		unsigned const	w,
		int &	msb_lo,
		int &	msb_hi,
		unsigned &	lsb
	)

Similar to doing two separate splits on the lower and upper half of input a.

See Also

split(int a, int n, int const w, int& msb, unsigned& lsb)

Parameters

a	Input as two lanes of 16 bits in a 32bit integer
n	Number of LSBs that shall end up in the fraction. This must be a compile time constant.
w	Width of the LUT in bytes on a binary logarithmic scale. The index will be shifted to the left by this value. This must be a compile time constant.
msb_lo	Lower order bits of output index into the LUT by reference
msb_hi	Higher order bits of output index into the LUT by reference
lsb	Output fraction for interpolation between msb and msb+1 in the LUT by reference (Two lanes of 16 bits each)

The instrinsic performs the following operations:

int a_lo = a & 0xFFFF;
int a_hi = (a >> 16) & 0xFFFF;
unsigned lsb_lo, lsb_hi;
split(a_lo,n,w,msb_lo,lsb_lo);
split(a_hi,n,w,msb_hi,lsb_hi);
lsb = (lsb_lo & 0xFFFF) | (lsb_hi << 16);