DCPS1, DCPS2, DCPS3

DCPSx, Debug Change PE State to ELx, where x is 1, 2, or 3.

When executed in Debug state, the target Exception level of the instruction is:

• ELx, if the instruction is executed at an Exception level lower than ELx.
• Otherwise, the Exception level at which the instruction is executed.

On executing a DCPSx instruction in Debug state when the instruction is not undefined:

• If the instruction is executed at an Exception level that is lower than the target Exception level the PE enters the target Exception level, Elx, and:
  • If ELx is using AArch64, the PE selects SP_ELx.
  • If the target Exception level is EL1 using AArch32 the PE enters Supervisor mode.
  • If the instruction was executed in Non-secure state and the target Exception level is EL2 using AArch32 the PE enters Hyp mode.
  • If the target Exception level is EL3 using AArch32 the PE enters Supervisor mode and SCR.NS is set to 0.
• Otherwise, there is no change to the Exception level and:
  • If the instruction was executed at EL1 the PE enters Supervisor mode.
  • If the instruction was executed at EL2 the PE remains in Hyp mode.
  • If the instruction was a DCPS1 instruction executed at EL3 the PE enters Supervisor mode and SCR.NS is set to 0.
  • If the instruction was a DCPS3 instruction executed at EL3 the PE enters Monitor mode and SCR.NS is set to 0.

These instructions are always undefined in Non-debug state.

DCPS1 is undefined at EL0 in Non-secure state if either:

• EL2 is usingimplemented AArch64 and enabledusing in the current Security state,AArch64 and HCR_EL2.TGE == 1.
• EL2 is implemented and using AArch32 in Non-Secure state, and HCR.TGE == 1.

DCPS2 is undefined at all Exception levels if EL2 is not implemented.

DCPS2 is undefined in the following states if EL2 is implemented:

• At EL0 and EL1, whenin EL2Secure isstate notif enabledSecure inEL2 theis current Security state.disabled.
• At EL3 if EL3 is using AArch32.

DCPS3 is undefined at all Exception levels if either:

• EDSCR.SDD == 1.
• EL3 is not implemented.

On executing a DCPSx instruction that is not undefined and targets ELx:

• If ELx is using AArch64:
  • ELR_ELx, SPSR_ELx, and ESR_ELx become unknown.
  • DLR_EL0 and DSPSR_EL0 become unknown.
• If ELx is using AArch32 DLR and DSPSR become unknown and:
  • If the target Exception level is EL1 or EL3, the LR and SPSR of the target PE mode become unknown.
  • If the target Exception level is EL2, then ELR_hyp, SPSR_hyp, and HSR become unknown.

For more information on the operation of these instructions, see DCPS.

T1

if !Halted() || opt == '00' then UNDEFINED;

Internal version only: isa v00_88v00_87, pseudocode v85-xml-00bet9_rc1_1v85-xml-00bet8_rc3 ; Build timestamp: 2018-12-12T122018-09-13T14:3300

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