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BTI

Branch target identification

This instruction is used to guard against the execution of instructions that are not the intended target of a branch.

Outside of a guarded memory region, a BTI instruction executes as a NOP. Within a guarded memory region, while PSTATE.BTYPE != 0b00, a BTI instruction compatible with the current value of PSTATE.BTYPE will not generate a Branch Target Exception and will allow execution of subsequent instructions within the memory region. For more information, see PSTATE.BTYPE.

The operand <targets> passed to a BTI instruction determines the values of PSTATE.BTYPE that the BTI instruction is compatible with.

System
(FEAT_BTI)

Decode for this encoding

if !IsFeatureImplemented(FEAT_BTI) then EndOfDecode(Decode_NOP); end; // Check branch target compatibility between BTI instruction and PSTATE.BTYPE SetBTypeCompatible(BTypeCompatible_BTI(op2[2:1]));