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<!---======================= begin_copyright_notice ============================
Copyright (C) 2020-2022 Intel Corporation
SPDX-License-Identifier: MIT
============================= end_copyright_notice ==========================-->
## Opcode
SAD2 = 0x16
## Format
| | | | | | |
| --- | --- | --- | --- | --- | --- |
| 0x16(SAD2) | Exec_size | Pred | Dst | Src0 | Src1 |
## Semantics
```
for (i = 0; i < exec_size; i += 1){
if (ChEn[i]) {
dst[i] = abs( src0[i] - src1[i] ) + abs ( src0[i+1] - src1[i+1] );
dst[i+1] = undefined;
}
}
```
## Description
```
Performs a two-wide sum-of-absolute-difference operation on a 2-tuple basis of <src0> and <src1>, and stores the scalar result to the first channel per 2-tuple in <dst>.
```
- **Exec_size(ub):** Execution size
- Bit[2..0]: size of the region for source and destination operands
- 0b000: 1 element (scalar)
- 0b001: 2 elements
- 0b010: 4 elements
- 0b011: 8 elements
- 0b100: 16 elements
- 0b101: 32 elements
- Bit[7..4]: execution mask (explicit control over the enabled channels)
- 0b0000: M1
- 0b0001: M2
- 0b0010: M3
- 0b0011: M4
- 0b0100: M5
- 0b0101: M6
- 0b0110: M7
- 0b0111: M8
- 0b1000: M1_NM
- 0b1001: M2_NM
- 0b1010: M3_NM
- 0b1011: M4_NM
- 0b1100: M5_NM
- 0b1101: M6_NM
- 0b1110: M7_NM
- 0b1111: M8_NM
- **Pred(uw):** Predication control
- **Dst(vec_operand):** The destination operand. Must have type W,UW. Operand class: general,indirect
- **Src0(vec_operand):** The first source operand. Must have type B,UB. Operand class: general,indirect,immediate
- **Src1(vec_operand):** The second source operand. Must have type B,UB. Operand class: general,indirect,immediate
#### Properties
- **Saturation:** Yes
- **Source Modifier:** arithmetic
## Text
```
[(<P>)] SAD2[.sat] (<exec_size>) <dst> <src0> <src1>
```
## Notes
```
The even elements of the <dst> will contain the correct data, while the odd element are updated with undefined values.
```
|
