addhnt

Add High Narrow (Top) (SVE2)

ADDHNT <Zd>.<T>, <Zn>.<Tb>, <Zm>.<Tb>

Adds wide elements, narrows, and stores in top half.

Pseudocode Operation

No pseudocode available.

Encoding

Binary Layout
01000101
31:24
size
23:22
1
21
Zm
20:16
011
15:13
0
12
0
11
1
10
Zn
9:5
Zd
4:0
 
Format SVE2 Math
Opcode 0x45206400
Extension SVE2

Operands

  • Zd
    Dest
  • Zn
    Src 1
  • Zm
    Src 2

Related

More in SVE2

Reference

View in Arm A64 ISA Reference ↗ Arm A64 ISA

Instruction Forms

Encoding Instruction ISA Bit pattern
0x45206400 ADDHNT <Zd>.<T>, <Zn>.<Tb>, <Zm>.<Tb> A64 01000101 | size | 1 | Zm | 011 | 0 | 0 | 1 | Zn | Zd

Description

Add each vector element of the first source vector to the corresponding vector element of the second source vector, and place the most significant half of the result in the odd-numbered half-width destination elements, leaving the even-numbered elements unchanged. This instruction is unpredicated.

Operation

CheckSVEEnabled();
constant integer VL = CurrentVL;
constant integer elements = VL DIV esize;
bits(VL) operand1 = Z[n, VL];
bits(VL) operand2 = Z[m, VL];
bits(VL) result = Z[d, VL];
constant integer halfesize = esize DIV 2;

for e = 0 to elements-1
    integer element1 = UInt(Elem[operand1, e, esize]);
    integer element2 = UInt(Elem[operand2, e, esize]);
    integer res = (element1 + element2) >> halfesize;
    Elem[result, 2*e + 1, halfesize] = res<halfesize-1:0>;

Z[d, VL] = result;