vl

Vector Length

Holds an unsigned integer specifying number of elements to be updated with results from a vector instruction.

Attributes

CSR Address	0xc20
Defining extension	V
Length	64-bit
Privilege Mode	U

CSR Address

0xc20

Defining extension

Length

64-bit

Privilege Mode

Format

Figure 1. vl format

Field Summary

Name Location Type Reset Value

Name	Location	Type	Reset Value
`VALUE`	63:0	RO-H	UNDEFINED_LEGAL

VALUE

63:0

RO-H

UNDEFINED_LEGAL

Fields

`VALUE`

Location

vl[63:0]

Description

The vl register holds an unsigned integer specifying the number of elements to be updated with results from a vector instruction, as further detailed in Section Section 31.5.4.

The number of bits implemented in vl depends on the implementation’s maximum vector length of the smallest supported type. The smallest vector implementation with VLEN=32 and supporting SEW=8 would need at least six bits in vl to hold the values 0-32 (VLEN=32, with LMUL=8 and SEW=8, yields VLMAX=32).

Type

RO-H	Read-Only with Hardware update Writes are ignored. Reads reflect a value dynamically generated by hardware.

Reset value: UNDEFINED_LEGAL