ipop.adoc

th.ipop

Synopsis

Pop register context from the interrupt stack

Mnemonic

ipop

Encoding

{reg:[
    { bits:  7, name: 0xb, attr: ['custom-0, 32 bit'] },
    { bits:  5, name: 0x0 },
    { bits:  3, name: 0x0 },
    { bits:  5, name: 0x0 },
    { bits:  5, name: 0x5 },
    { bits:  7, name: 0x0 },
]}

Description

This instruction restores the following information from the interrupt stack:

• mcause

• mepc

• callee-saved registers (X1, X5-X7, X10-X17, and X28-X31)

Additionally the interrupt stack pointer is moved back accordingly.

Operation

{mcause, mepc, X1, X5-X7, X10-X17, X28-X31} := mem[int_sp+68:int_sp]
int_sp := int_sp + 72
mret

Permission

This instruction can be executed in M mode only. Attempts to execute this instruction in other modes will raise an illegal instruction exception.

Exceptions

This instruction does not trigger any exceptions.

Included in

Extension
XTheadFmv ([xtheadint])