gcsss2

Guarded Control Stack Switch Stack 2

GCSSS2 <Xt>

Second step to switch the GCS pointer.

Pseudocode Operation

if FEAT_GCS == '0' then
  UNDEFINED
else if PSTATE.EL == EL0 then
  UNDEFINED
else
  GCSSwitchStack2(X[t])

Example

GCSSS2 x3

Encoding

Binary Layout

1101010100

31:22

1

21

01

20:19

011

18:16

0111

15:12

0111

11:8

011

7:5

Rt

4:0

 

Format System

Opcode 0xD52B7760

Extension FEAT_GCS (Security)

Operands

• Xt
  New Stack Ptr

Related

More in FEAT_GCS (Security)

Reference

View in Arm A64 ISA Reference ↗ Arm A64 ISA

Instruction Forms

Encoding	Instruction		ISA		Bit pattern
0xD52B7760	GCSSS2 <Xt>		A64		1101010100 | 1 | 01 | 011 | 0111 | 0111 | 011 | Rt

Description

Guarded Control Stack Switch Stack 2 validates that the most recent entry of the Guarded control stack being switched to contains an In-progress cap entry, stores a Valid cap entry to the Guarded control stack that is being switched from, and sets Xt to the Guarded control stack pointer that is being switched from.