Base Instructions | SIMD&FP Instructions | SVE Instructions | SME Instructions | Index by Encoding | Shared Pseudocode | Proprietary Notice

## HVC

Hypervisor Call causes an exception to EL2. Software executing at EL1 can use this instruction to call the hypervisor to request a service.

The HVC instruction is undefined:

- When EL3 is implemented and SCR_EL3.HCE is set to 0.
- When EL3 is not implemented and HCR_EL2.HCD is set to 1.
- When EL2 is not implemented.
- At EL1 if EL2 is not enabled in the current Security state.
- At EL0.

On executing an HVC instruction, the PE records the exception as a Hypervisor Call exception in ESR_ELx, using the EC value 0x16, and the value of the immediate argument.

31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0
1 | 1 | 0 | 1 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | imm16 | 0 | 0 | 0 | 1 | 0

####

HVC #<imm>

// Empty.

### Assembler Symbols

<imm> | Is a 16-bit unsigned immediate, in the range 0 to 65535, encoded in the "imm16" field.

### Operation

if !HaveEL(EL2) || PSTATE.EL == EL0 || (PSTATE.EL == EL1 && !EL2Enabled()) then UNDEFINED; bits(1) hvc_enable = if HaveEL(EL3) then SCR_EL3.HCE else NOT(HCR_EL2.HCD); if hvc_enable == '0' then UNDEFINED; else AArch64.CallHypervisor(imm16);

Base Instructions | SIMD&FP Instructions | SVE Instructions | SME Instructions | Index by Encoding | Shared Pseudocode | Proprietary Notice

Internal version only: isa v33.64, AdvSIMD v29.12, pseudocode v2023-06_rel, sve v2023-06_rel ; Build timestamp: 2023-07-04T19:42

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