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GMI -- A64

GMI

Tag mask insert

This instruction inserts the tag in the first source register into the excluded set specified in the second source register, writing the new excluded set to the destination register.

Integer
(FEAT_MTE)

313029282726252423222120191817161514131211109876543210
10011010110Rm000101RnRd
sfSopcode

Encoding

GMI <Xd>, <Xn|SP>, <Xm>

Decode for this encoding

if !IsFeatureImplemented(FEAT_MTE) then EndOfDecode(Decode_UNDEF); end; let d : integer{} = UInt(Rd); let n : integer{} = UInt(Rn); let m : integer{} = UInt(Rm);

Assembler Symbols

<Xd>

Is the 64-bit name of the general-purpose destination register, encoded in the "Rd" field.

<Xn|SP>

Is the 64-bit name of the first source general-purpose register or stack pointer, encoded in the "Rn" field.

<Xm>

Is the 64-bit name of the second general-purpose source register, encoded in the "Rm" field.

Operation

let address : bits(64) = if n == 31 then SP{64}() else X{64}(n); var mask : bits(64) = X{}(m); let tag : bits(4) = AArch64_AllocationTagFromAddress(address); mask[UInt(tag)] = '1'; X{64}(d) = mask;


2026-03_rel 2026-03-26 20:48:11

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