VCPOP.V

Vector Population Count

VCPOP.V vd, vs2, vm

Counts the number of set bits (1s) in each element.

Encoding

Binary Layout

010010

31:26

vm

25

vs2

24:20

01110010

19:12

vd

11:7

1010111

6:0

 

Format OPIVV

Opcode 0x48072057

Extension Zvbb

Operands

• vd
  Destination vector register
• vs2
  Source vector register 2

Example

VCPOP.V v1, v4, v0.t

Related

More in Zvbb

Reference

View in RISC-V Unprivileged ISA Specification ↗ RISC-V ISA Manual

Description

Counts the number of set bits in mask register vs2 that are active (within vl), writing the count to scalar rd.

Operation

foreach(i < vl): vd[i] = count_set_bits(vs2[i]);