VSETVLI

Vector Set VL Immediate

VSETVLI rd, rs1, vtypei

Configures the vector length (vl) and vector type (vtype) based on application needs.

Encoding

Binary Layout

0

31

zimm11

30:20

rs1

19:15

111

14:12

rd

11:7

1010111

6:0

 

Format V-Type

Opcode 0x00007057

Extension V

Operands

• rd
  Dest (Actual VL)
• rs1
  Req VL (Avail)
• vtypei
  Config (SEW/LMUL)

Example

VSETVLI t0, a0, e32, m1, ta, ma

// Request VL=a0, 32-bit elements, 1 register group.

Related

More in V

Reference

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

Description

Sets the vector length (vl) and vector type (vtype) registers based on the requested application vector length (AVL) and element width/grouping. The actual vector length set is written to rd. vtype encodes SEW (element width), LMUL (register grouping), and tail/mask policies.

Operation

vl = set_config(rs1, vtypei); R[rd] = vl;