ENDBR64 — Terminate an Indirect Branch in 64-bit Mode

Opcode/Instruction	Op / En	64/32 bit Mode Support	CPUID Feature Flag	Description
F3 0F 1E FA ENDBR64	ZO	V/V	CET_IBT	Terminate indirect branch in 64-bit mode.

Instruction Operand Encoding ¶

Op/En	Tuple Type	Operand 1	Operand 2	Operand 3	Operand 4
ZO	N/A	N/A	N/A	N/A	N/A

Description ¶

Terminate an indirect branch in 64 bit mode.

Operation ¶

IF EndbranchEnabled(CPL) & IA32_EFER.LMA = 1 & CS.L = 1
    IF CPL = 3
        THEN
            IA32_U_CET.TRACKER = IDLE
            IA32_U_CET.SUPPRESS = 0
        ELSE
            IA32_S_CET.TRACKER = IDLE
            IA32_S_CET.SUPPRESS = 0
    FI;
FI;

Flags Affected ¶

None.

Exceptions ¶

None.